/* $FreeBSD$ */ /* * Copyright (C) 1993-2003 by Darren Reed. * * See the IPFILTER.LICENCE file for details on licencing. */ #if defined(KERNEL) || defined(_KERNEL) # undef KERNEL # undef _KERNEL # define KERNEL 1 # define _KERNEL 1 #endif #include #include #include #include #if defined(__NetBSD__) # if (NetBSD >= 199905) && !defined(IPFILTER_LKM) && defined(_KERNEL) # if (__NetBSD_Version__ < 301000000) # include "opt_ipfilter_log.h" # else # include "opt_ipfilter.h" # endif # endif #endif #if defined(_KERNEL) && defined(__FreeBSD_version) && \ (__FreeBSD_version >= 220000) # if (__FreeBSD_version >= 400000) # if !defined(IPFILTER_LKM) # include "opt_inet6.h" # endif # if (__FreeBSD_version == 400019) # define CSUM_DELAY_DATA # endif # endif # include #else # include #endif #if (defined(__SVR4) || defined(__svr4__)) && defined(sun) # include #endif #if !defined(_AIX51) # include #endif #if defined(_KERNEL) # include # include #else # include # include # include # include # include # define _KERNEL # ifdef __OpenBSD__ struct file; # endif # include # undef _KERNEL #endif #if !defined(__SVR4) && !defined(__svr4__) && !defined(__hpux) && \ !defined(linux) # include #else # if !defined(linux) # include # endif # if (SOLARIS2 < 5) && defined(sun) # include # endif #endif #ifdef __hpux # define _NET_ROUTE_INCLUDED #endif #if !defined(linux) # include #endif #include #include #ifdef sun # include #endif #if !defined(_KERNEL) && (defined(__FreeBSD__) || defined(SOLARIS2)) # if (__FreeBSD_version >= 504000) # undef _RADIX_H_ # endif # include "radix_ipf.h" #endif #ifdef __osf__ # include "radix_ipf.h" #else # include #endif #include #include #include #if !defined(linux) # include #endif #if defined(__sgi) && defined(IFF_DRVRLOCK) /* IRIX 6 */ # include # include #endif #include #if (!defined(__sgi) && !defined(AIX)) || defined(_KERNEL) # include # include #endif #ifdef __hpux # undef _NET_ROUTE_INCLUDED #endif #ifdef __osf__ # undef _RADIX_H_ #endif #include "netinet/ip_compat.h" #ifdef USE_INET6 # include # if !SOLARIS && defined(_KERNEL) && !defined(__osf__) && !defined(__hpux) # include # endif #endif #include #include "netinet/ip_fil.h" #include "netinet/ip_nat.h" #include "netinet/ip_frag.h" #include "netinet/ip_state.h" #include "netinet/ip_proxy.h" #include "netinet/ip_auth.h" #ifdef IPFILTER_SCAN # include "netinet/ip_scan.h" #endif #ifdef IPFILTER_SYNC # include "netinet/ip_sync.h" #endif #include "netinet/ip_pool.h" #include "netinet/ip_htable.h" #ifdef IPFILTER_COMPILED # include "netinet/ip_rules.h" #endif #if defined(IPFILTER_BPF) && defined(_KERNEL) # include #endif #if defined(__FreeBSD_version) && (__FreeBSD_version >= 300000) # include # if defined(_KERNEL) && !defined(IPFILTER_LKM) # include "opt_ipfilter.h" # endif #endif #include "netinet/ipl.h" /* END OF INCLUDES */ #include #if !defined(lint) static const char sccsid[] = "@(#)fil.c 1.36 6/5/96 (C) 1993-2000 Darren Reed"; static const char rcsid[] = "@(#)$FreeBSD$"; /* static const char rcsid[] = "@(#)$Id: fil.c,v 2.243.2.125 2007/10/10 09:27:20 darrenr Exp $"; */ #endif #ifndef _KERNEL # include "ipf.h" # include "ipt.h" # include "bpf-ipf.h" extern int opts; #endif /* _KERNEL */ fr_info_t frcache[2][8]; struct filterstats frstats[2]; struct frentry *ipfilter[2][2] = { { NULL, NULL }, { NULL, NULL } }, *ipfilter6[2][2] = { { NULL, NULL }, { NULL, NULL } }, *ipacct6[2][2] = { { NULL, NULL }, { NULL, NULL } }, *ipacct[2][2] = { { NULL, NULL }, { NULL, NULL } }, *ipnatrules[2][2] = { { NULL, NULL }, { NULL, NULL } }; struct frgroup *ipfgroups[IPL_LOGSIZE][2]; char ipfilter_version[] = IPL_VERSION; int fr_refcnt = 0; /* * For fr_running: * 0 == loading, 1 = running, -1 = disabled, -2 = unloading */ int fr_running = 0; int fr_flags = IPF_LOGGING; int fr_active = 0; int fr_control_forwarding = 0; int fr_update_ipid = 0; u_short fr_ip_id = 0; int fr_chksrc = 0; /* causes a system crash if enabled */ int fr_minttl = 4; int fr_icmpminfragmtu = 68; u_long fr_frouteok[2] = {0, 0}; u_long fr_userifqs = 0; u_long fr_badcoalesces[2] = {0, 0}; u_char ipf_iss_secret[32]; #if defined(IPFILTER_DEFAULT_BLOCK) int fr_pass = FR_BLOCK|FR_NOMATCH; #else int fr_pass = (IPF_DEFAULT_PASS)|FR_NOMATCH; #endif int fr_features = 0 #ifdef IPFILTER_LKM | IPF_FEAT_LKM #endif #ifdef IPFILTER_LOG | IPF_FEAT_LOG #endif #ifdef IPFILTER_LOOKUP | IPF_FEAT_LOOKUP #endif #ifdef IPFILTER_BPF | IPF_FEAT_BPF #endif #ifdef IPFILTER_COMPILED | IPF_FEAT_COMPILED #endif #ifdef IPFILTER_CKSUM | IPF_FEAT_CKSUM #endif #ifdef IPFILTER_SYNC | IPF_FEAT_SYNC #endif #ifdef IPFILTER_SCAN | IPF_FEAT_SCAN #endif #ifdef USE_INET6 | IPF_FEAT_IPV6 #endif ; static INLINE int fr_ipfcheck __P((fr_info_t *, frentry_t *, int)); static int fr_portcheck __P((frpcmp_t *, u_short *)); static int frflushlist __P((int, minor_t, int *, frentry_t **)); static ipfunc_t fr_findfunc __P((ipfunc_t)); static frentry_t *fr_firewall __P((fr_info_t *, u_32_t *)); static int fr_funcinit __P((frentry_t *fr)); static INLINE void frpr_ah __P((fr_info_t *)); static INLINE void frpr_esp __P((fr_info_t *)); static INLINE void frpr_gre __P((fr_info_t *)); static INLINE void frpr_udp __P((fr_info_t *)); static INLINE void frpr_tcp __P((fr_info_t *)); static INLINE void frpr_icmp __P((fr_info_t *)); static INLINE void frpr_ipv4hdr __P((fr_info_t *)); static INLINE int frpr_pullup __P((fr_info_t *, int)); static INLINE void frpr_short __P((fr_info_t *, int)); static INLINE int frpr_tcpcommon __P((fr_info_t *)); static INLINE int frpr_udpcommon __P((fr_info_t *)); static int fr_updateipid __P((fr_info_t *)); #ifdef IPFILTER_LOOKUP static int fr_grpmapinit __P((frentry_t *fr)); static INLINE void *fr_resolvelookup __P((u_int, u_int, i6addr_t *, lookupfunc_t *)); #endif static void frsynclist __P((frentry_t *, void *)); static ipftuneable_t *fr_findtunebyname __P((const char *)); static ipftuneable_t *fr_findtunebycookie __P((void *, void **)); static int ipf_geniter __P((ipftoken_t *, ipfgeniter_t *)); static int ipf_frruleiter __P((void *, int, void *)); static void ipf_unlinktoken __P((ipftoken_t *)); /* * bit values for identifying presence of individual IP options * All of these tables should be ordered by increasing key value on the left * hand side to allow for binary searching of the array and include a trailer * with a 0 for the bitmask for linear searches to easily find the end with. */ const struct optlist ipopts[20] = { { IPOPT_NOP, 0x000001 }, { IPOPT_RR, 0x000002 }, { IPOPT_ZSU, 0x000004 }, { IPOPT_MTUP, 0x000008 }, { IPOPT_MTUR, 0x000010 }, { IPOPT_ENCODE, 0x000020 }, { IPOPT_TS, 0x000040 }, { IPOPT_TR, 0x000080 }, { IPOPT_SECURITY, 0x000100 }, { IPOPT_LSRR, 0x000200 }, { IPOPT_E_SEC, 0x000400 }, { IPOPT_CIPSO, 0x000800 }, { IPOPT_SATID, 0x001000 }, { IPOPT_SSRR, 0x002000 }, { IPOPT_ADDEXT, 0x004000 }, { IPOPT_VISA, 0x008000 }, { IPOPT_IMITD, 0x010000 }, { IPOPT_EIP, 0x020000 }, { IPOPT_FINN, 0x040000 }, { 0, 0x000000 } }; #ifdef USE_INET6 struct optlist ip6exthdr[] = { { IPPROTO_HOPOPTS, 0x000001 }, { IPPROTO_IPV6, 0x000002 }, { IPPROTO_ROUTING, 0x000004 }, { IPPROTO_FRAGMENT, 0x000008 }, { IPPROTO_ESP, 0x000010 }, { IPPROTO_AH, 0x000020 }, { IPPROTO_NONE, 0x000040 }, { IPPROTO_DSTOPTS, 0x000080 }, { IPPROTO_MOBILITY, 0x000100 }, { 0, 0 } }; #endif struct optlist tcpopts[] = { { TCPOPT_NOP, 0x000001 }, { TCPOPT_MAXSEG, 0x000002 }, { TCPOPT_WINDOW, 0x000004 }, { TCPOPT_SACK_PERMITTED, 0x000008 }, { TCPOPT_SACK, 0x000010 }, { TCPOPT_TIMESTAMP, 0x000020 }, { 0, 0x000000 } }; /* * bit values for identifying presence of individual IP security options */ const struct optlist secopt[8] = { { IPSO_CLASS_RES4, 0x01 }, { IPSO_CLASS_TOPS, 0x02 }, { IPSO_CLASS_SECR, 0x04 }, { IPSO_CLASS_RES3, 0x08 }, { IPSO_CLASS_CONF, 0x10 }, { IPSO_CLASS_UNCL, 0x20 }, { IPSO_CLASS_RES2, 0x40 }, { IPSO_CLASS_RES1, 0x80 } }; /* * Table of functions available for use with call rules. */ static ipfunc_resolve_t fr_availfuncs[] = { #ifdef IPFILTER_LOOKUP { "fr_srcgrpmap", fr_srcgrpmap, fr_grpmapinit }, { "fr_dstgrpmap", fr_dstgrpmap, fr_grpmapinit }, #endif { "", NULL, NULL } }; /* * The next section of code is a a collection of small routines that set * fields in the fr_info_t structure passed based on properties of the * current packet. There are different routines for the same protocol * for each of IPv4 and IPv6. Adding a new protocol, for which there * will "special" inspection for setup, is now more easily done by adding * a new routine and expanding the frpr_ipinit*() function rather than by * adding more code to a growing switch statement. */ #ifdef USE_INET6 static INLINE int frpr_ah6 __P((fr_info_t *)); static INLINE void frpr_esp6 __P((fr_info_t *)); static INLINE void frpr_gre6 __P((fr_info_t *)); static INLINE void frpr_udp6 __P((fr_info_t *)); static INLINE void frpr_tcp6 __P((fr_info_t *)); static INLINE void frpr_icmp6 __P((fr_info_t *)); static INLINE int frpr_ipv6hdr __P((fr_info_t *)); static INLINE void frpr_short6 __P((fr_info_t *, int)); static INLINE int frpr_hopopts6 __P((fr_info_t *)); static INLINE int frpr_mobility6 __P((fr_info_t *)); static INLINE int frpr_routing6 __P((fr_info_t *)); static INLINE int frpr_dstopts6 __P((fr_info_t *)); static INLINE int frpr_fragment6 __P((fr_info_t *)); static INLINE int frpr_ipv6exthdr __P((fr_info_t *, int, int)); /* ------------------------------------------------------------------------ */ /* Function: frpr_short6 */ /* Returns: void */ /* Parameters: fin(I) - pointer to packet information */ /* */ /* IPv6 Only */ /* This is function enforces the 'is a packet too short to be legit' rule */ /* for IPv6 and marks the packet with FI_SHORT if so. See function comment */ /* for frpr_short() for more details. */ /* ------------------------------------------------------------------------ */ static INLINE void frpr_short6(fin, xmin) fr_info_t *fin; int xmin; { if (fin->fin_dlen < xmin) fin->fin_flx |= FI_SHORT; } /* ------------------------------------------------------------------------ */ /* Function: frpr_ipv6hdr */ /* Returns: int - 0 = IPv6 packet intact, -1 = packet lost */ /* Parameters: fin(I) - pointer to packet information */ /* */ /* IPv6 Only */ /* Copy values from the IPv6 header into the fr_info_t struct and call the */ /* per-protocol analyzer if it exists. In validating the packet, a protocol*/ /* analyzer may pullup or free the packet itself so we need to be vigiliant */ /* of that possibility arising. */ /* ------------------------------------------------------------------------ */ static INLINE int frpr_ipv6hdr(fin) fr_info_t *fin; { ip6_t *ip6 = (ip6_t *)fin->fin_ip; int p, go = 1, i, hdrcount; fr_ip_t *fi = &fin->fin_fi; fin->fin_off = 0; fi->fi_tos = 0; fi->fi_optmsk = 0; fi->fi_secmsk = 0; fi->fi_auth = 0; p = ip6->ip6_nxt; fi->fi_ttl = ip6->ip6_hlim; fi->fi_src.in6 = ip6->ip6_src; fi->fi_dst.in6 = ip6->ip6_dst; fin->fin_id = (u_short)(ip6->ip6_flow & 0xffff); hdrcount = 0; while (go && !(fin->fin_flx & (FI_BAD|FI_SHORT))) { switch (p) { case IPPROTO_UDP : frpr_udp6(fin); go = 0; break; case IPPROTO_TCP : frpr_tcp6(fin); go = 0; break; case IPPROTO_ICMPV6 : frpr_icmp6(fin); go = 0; break; case IPPROTO_GRE : frpr_gre6(fin); go = 0; break; case IPPROTO_HOPOPTS : p = frpr_hopopts6(fin); break; case IPPROTO_MOBILITY : p = frpr_mobility6(fin); break; case IPPROTO_DSTOPTS : p = frpr_dstopts6(fin); break; case IPPROTO_ROUTING : p = frpr_routing6(fin); break; case IPPROTO_AH : p = frpr_ah6(fin); break; case IPPROTO_ESP : frpr_esp6(fin); go = 0; break; case IPPROTO_IPV6 : for (i = 0; ip6exthdr[i].ol_bit != 0; i++) if (ip6exthdr[i].ol_val == p) { fin->fin_flx |= ip6exthdr[i].ol_bit; break; } go = 0; break; case IPPROTO_NONE : go = 0; break; case IPPROTO_FRAGMENT : p = frpr_fragment6(fin); if (fin->fin_off != 0) go = 0; break; default : go = 0; break; } hdrcount++; /* * It is important to note that at this point, for the * extension headers (go != 0), the entire header may not have * been pulled up when the code gets to this point. This is * only done for "go != 0" because the other header handlers * will all pullup their complete header. The other indicator * of an incomplete packet is that this was just an extension * header. */ if ((go != 0) && (p != IPPROTO_NONE) && (frpr_pullup(fin, 0) == -1)) { p = IPPROTO_NONE; go = 0; } } fi->fi_p = p; /* * Some of the above functions, like frpr_esp6(), can call fr_pullup * and destroy whatever packet was here. The caller of this function * expects us to return -1 if there is a problem with fr_pullup. */ if (fin->fin_m == NULL) return -1; return 0; } /* ------------------------------------------------------------------------ */ /* Function: frpr_ipv6exthdr */ /* Returns: int - value of the next header or IPPROTO_NONE if error */ /* Parameters: fin(I) - pointer to packet information */ /* multiple(I) - flag indicating yes/no if multiple occurances */ /* of this extension header are allowed. */ /* proto(I) - protocol number for this extension header */ /* */ /* IPv6 Only */ /* ------------------------------------------------------------------------ */ static INLINE int frpr_ipv6exthdr(fin, multiple, proto) fr_info_t *fin; int multiple, proto; { struct ip6_ext *hdr; u_short shift; int i; fin->fin_flx |= FI_V6EXTHDR; /* 8 is default length of extension hdr */ if ((fin->fin_dlen - 8) < 0) { fin->fin_flx |= FI_SHORT; return IPPROTO_NONE; } if (frpr_pullup(fin, 8) == -1) return IPPROTO_NONE; hdr = fin->fin_dp; switch (proto) { case IPPROTO_FRAGMENT : shift = 8; break; default : shift = 8 + (hdr->ip6e_len << 3); break; } if (shift > fin->fin_dlen) { /* Nasty extension header length? */ fin->fin_flx |= FI_BAD; return IPPROTO_NONE; } for (i = 0; ip6exthdr[i].ol_bit != 0; i++) if (ip6exthdr[i].ol_val == proto) { /* * Most IPv6 extension headers are only allowed once. */ if ((multiple == 0) && ((fin->fin_optmsk & ip6exthdr[i].ol_bit) != 0)) fin->fin_flx |= FI_BAD; else fin->fin_optmsk |= ip6exthdr[i].ol_bit; break; } fin->fin_exthdr = fin->fin_dp; fin->fin_dp = (char *)fin->fin_dp + shift; fin->fin_dlen -= shift; return hdr->ip6e_nxt; } /* ------------------------------------------------------------------------ */ /* Function: frpr_hopopts6 */ /* Returns: int - value of the next header or IPPROTO_NONE if error */ /* Parameters: fin(I) - pointer to packet information */ /* */ /* IPv6 Only */ /* This is function checks pending hop by hop options extension header */ /* ------------------------------------------------------------------------ */ static INLINE int frpr_hopopts6(fin) fr_info_t *fin; { return frpr_ipv6exthdr(fin, 0, IPPROTO_HOPOPTS); } /* ------------------------------------------------------------------------ */ /* Function: frpr_mobility6 */ /* Returns: int - value of the next header or IPPROTO_NONE if error */ /* Parameters: fin(I) - pointer to packet information */ /* */ /* IPv6 Only */ /* This is function checks the IPv6 mobility extension header */ /* ------------------------------------------------------------------------ */ static INLINE int frpr_mobility6(fin) fr_info_t *fin; { return frpr_ipv6exthdr(fin, 0, IPPROTO_MOBILITY); } /* ------------------------------------------------------------------------ */ /* Function: frpr_routing6 */ /* Returns: int - value of the next header or IPPROTO_NONE if error */ /* Parameters: fin(I) - pointer to packet information */ /* */ /* IPv6 Only */ /* This is function checks pending routing extension header */ /* ------------------------------------------------------------------------ */ static INLINE int frpr_routing6(fin) fr_info_t *fin; { struct ip6_ext *hdr; if (frpr_ipv6exthdr(fin, 0, IPPROTO_ROUTING) == IPPROTO_NONE) return IPPROTO_NONE; hdr = fin->fin_exthdr; if ((hdr->ip6e_len & 1) != 0) { /* * The routing header data is made up of 128 bit IPv6 addresses * which means it must be a multiple of 2 lots of 8 in length. */ fin->fin_flx |= FI_BAD; /* * Compensate for the changes made in frpr_ipv6exthdr() */ fin->fin_dlen += 8 + (hdr->ip6e_len << 3); fin->fin_dp = hdr; return IPPROTO_NONE; } return hdr->ip6e_nxt; } /* ------------------------------------------------------------------------ */ /* Function: frpr_fragment6 */ /* Returns: int - value of the next header or IPPROTO_NONE if error */ /* Parameters: fin(I) - pointer to packet information */ /* */ /* IPv6 Only */ /* Examine the IPv6 fragment header and extract fragment offset information.*/ /* */ /* We don't know where the transport layer header (or whatever is next is), */ /* as it could be behind destination options (amongst others). Because */ /* there is no fragment cache, there is no knowledge about whether or not an*/ /* upper layer header has been seen (or where it ends) and thus we are not */ /* able to continue processing beyond this header with any confidence. */ /* ------------------------------------------------------------------------ */ static INLINE int frpr_fragment6(fin) fr_info_t *fin; { struct ip6_frag *frag; int extoff; fin->fin_flx |= FI_FRAG; if (frpr_ipv6exthdr(fin, 0, IPPROTO_FRAGMENT) == IPPROTO_NONE) return IPPROTO_NONE; extoff = (char *)fin->fin_exthdr - (char *)fin->fin_dp; if (frpr_pullup(fin, sizeof(*frag)) == -1) return IPPROTO_NONE; fin->fin_exthdr = (char *)fin->fin_dp + extoff; frag = fin->fin_exthdr; /* * Fragment but no fragmentation info set? Bad packet... */ if (frag->ip6f_offlg == 0) { fin->fin_flx |= FI_BAD; return IPPROTO_NONE; } fin->fin_off = ntohs(frag->ip6f_offlg & IP6F_OFF_MASK); fin->fin_off <<= 3; if (fin->fin_off != 0) fin->fin_flx |= FI_FRAGBODY; fin->fin_dp = (char *)fin->fin_dp + sizeof(*frag); fin->fin_dlen -= sizeof(*frag); return frag->ip6f_nxt; } /* ------------------------------------------------------------------------ */ /* Function: frpr_dstopts6 */ /* Returns: int - value of the next header or IPPROTO_NONE if error */ /* Parameters: fin(I) - pointer to packet information */ /* nextheader(I) - stores next header value */ /* */ /* IPv6 Only */ /* This is function checks pending destination options extension header */ /* ------------------------------------------------------------------------ */ static INLINE int frpr_dstopts6(fin) fr_info_t *fin; { return frpr_ipv6exthdr(fin, 1, IPPROTO_DSTOPTS); } /* ------------------------------------------------------------------------ */ /* Function: frpr_icmp6 */ /* Returns: void */ /* Parameters: fin(I) - pointer to packet information */ /* */ /* IPv6 Only */ /* This routine is mainly concerned with determining the minimum valid size */ /* for an ICMPv6 packet. */ /* ------------------------------------------------------------------------ */ static INLINE void frpr_icmp6(fin) fr_info_t *fin; { int minicmpsz = sizeof(struct icmp6_hdr); struct icmp6_hdr *icmp6; if (frpr_pullup(fin, ICMP6ERR_MINPKTLEN - sizeof(ip6_t)) == -1) return; if (fin->fin_dlen > 1) { ip6_t *ip6; icmp6 = fin->fin_dp; fin->fin_data[0] = *(u_short *)icmp6; switch (icmp6->icmp6_type) { case ICMP6_ECHO_REPLY : case ICMP6_ECHO_REQUEST : minicmpsz = ICMP6ERR_MINPKTLEN - sizeof(ip6_t); break; case ICMP6_DST_UNREACH : case ICMP6_PACKET_TOO_BIG : case ICMP6_TIME_EXCEEDED : case ICMP6_PARAM_PROB : fin->fin_flx |= FI_ICMPERR; minicmpsz = ICMP6ERR_IPICMPHLEN - sizeof(ip6_t); if (fin->fin_plen < ICMP6ERR_IPICMPHLEN) break; if (M_LEN(fin->fin_m) < fin->fin_plen) { if (fr_coalesce(fin) != 1) return; } /* * If the destination of this packet doesn't match the * source of the original packet then this packet is * not correct. */ icmp6 = fin->fin_dp; ip6 = (ip6_t *)((char *)icmp6 + ICMPERR_ICMPHLEN); if (IP6_NEQ(&fin->fin_fi.fi_dst, (i6addr_t *)&ip6->ip6_src)) fin->fin_flx |= FI_BAD; break; default : break; } } frpr_short6(fin, minicmpsz); } /* ------------------------------------------------------------------------ */ /* Function: frpr_udp6 */ /* Returns: void */ /* Parameters: fin(I) - pointer to packet information */ /* */ /* IPv6 Only */ /* Analyse the packet for IPv6/UDP properties. */ /* Is not expected to be called for fragmented packets. */ /* ------------------------------------------------------------------------ */ static INLINE void frpr_udp6(fin) fr_info_t *fin; { frpr_short6(fin, sizeof(struct udphdr)); if (frpr_udpcommon(fin) == 0) { u_char p = fin->fin_p; fin->fin_p = IPPROTO_UDP; fr_checkv6sum(fin); fin->fin_p = p; } } /* ------------------------------------------------------------------------ */ /* Function: frpr_tcp6 */ /* Returns: void */ /* Parameters: fin(I) - pointer to packet information */ /* */ /* IPv6 Only */ /* Analyse the packet for IPv6/TCP properties. */ /* Is not expected to be called for fragmented packets. */ /* ------------------------------------------------------------------------ */ static INLINE void frpr_tcp6(fin) fr_info_t *fin; { frpr_short6(fin, sizeof(struct tcphdr)); if (frpr_tcpcommon(fin) == 0) { u_char p = fin->fin_p; fin->fin_p = IPPROTO_TCP; fr_checkv6sum(fin); fin->fin_p = p; } } /* ------------------------------------------------------------------------ */ /* Function: frpr_esp6 */ /* Returns: void */ /* Parameters: fin(I) - pointer to packet information */ /* */ /* IPv6 Only */ /* Analyse the packet for ESP properties. */ /* The minimum length is taken to be the SPI (32bits) plus a tail (32bits) */ /* even though the newer ESP packets must also have a sequence number that */ /* is 32bits as well, it is not possible(?) to determine the version from a */ /* simple packet header. */ /* ------------------------------------------------------------------------ */ static INLINE void frpr_esp6(fin) fr_info_t *fin; { frpr_short6(fin, sizeof(grehdr_t)); (void) frpr_pullup(fin, 8); } /* ------------------------------------------------------------------------ */ /* Function: frpr_ah6 */ /* Returns: void */ /* Parameters: fin(I) - pointer to packet information */ /* */ /* IPv6 Only */ /* Analyse the packet for AH properties. */ /* The minimum length is taken to be the combination of all fields in the */ /* header being present and no authentication data (null algorithm used.) */ /* ------------------------------------------------------------------------ */ static INLINE int frpr_ah6(fin) fr_info_t *fin; { authhdr_t *ah; frpr_short6(fin, 12); if (frpr_pullup(fin, sizeof(*ah)) == -1) return IPPROTO_NONE; ah = (authhdr_t *)fin->fin_dp; return ah->ah_next; } /* ------------------------------------------------------------------------ */ /* Function: frpr_gre6 */ /* Returns: void */ /* Parameters: fin(I) - pointer to packet information */ /* */ /* Analyse the packet for GRE properties. */ /* ------------------------------------------------------------------------ */ static INLINE void frpr_gre6(fin) fr_info_t *fin; { grehdr_t *gre; frpr_short6(fin, sizeof(grehdr_t)); if (frpr_pullup(fin, sizeof(grehdr_t)) == -1) return; gre = fin->fin_dp; if (GRE_REV(gre->gr_flags) == 1) fin->fin_data[0] = gre->gr_call; } #endif /* USE_INET6 */ /* ------------------------------------------------------------------------ */ /* Function: frpr_pullup */ /* Returns: int - 0 == pullup succeeded, -1 == failure */ /* Parameters: fin(I) - pointer to packet information */ /* plen(I) - length (excluding L3 header) to pullup */ /* */ /* Short inline function to cut down on code duplication to perform a call */ /* to fr_pullup to ensure there is the required amount of data, */ /* consecutively in the packet buffer. */ /* */ /* This function pulls up 'extra' data at the location of fin_dp. fin_dp */ /* points to the first byte after the complete layer 3 header, which will */ /* include all of the known extension headers for IPv6 or options for IPv4. */ /* */ /* Since fr_pullup() expects the total length of bytes to be pulled up, it */ /* is necessary to add those we can already assume to be pulled up (fin_dp */ /* - fin_ip) to what is passed through. */ /* ------------------------------------------------------------------------ */ static INLINE int frpr_pullup(fin, plen) fr_info_t *fin; int plen; { if (fin->fin_m != NULL) { if (fin->fin_dp != NULL) plen += (char *)fin->fin_dp - ((char *)fin->fin_ip + fin->fin_hlen); plen += fin->fin_hlen; if (M_LEN(fin->fin_m) < plen) { #if defined(_KERNEL) if (fr_pullup(fin->fin_m, fin, plen) == NULL) return -1; #else /* * Fake fr_pullup failing */ *fin->fin_mp = NULL; fin->fin_m = NULL; fin->fin_ip = NULL; return -1; #endif } } return 0; } /* ------------------------------------------------------------------------ */ /* Function: frpr_short */ /* Returns: void */ /* Parameters: fin(I) - pointer to packet information */ /* xmin(I) - minimum header size */ /* */ /* Check if a packet is "short" as defined by xmin. The rule we are */ /* applying here is that the packet must not be fragmented within the layer */ /* 4 header. That is, it must not be a fragment that has its offset set to */ /* start within the layer 4 header (hdrmin) or if it is at offset 0, the */ /* entire layer 4 header must be present (min). */ /* ------------------------------------------------------------------------ */ static INLINE void frpr_short(fin, xmin) fr_info_t *fin; int xmin; { if (fin->fin_off == 0) { if (fin->fin_dlen < xmin) fin->fin_flx |= FI_SHORT; } else if (fin->fin_off < xmin) { fin->fin_flx |= FI_SHORT; } } /* ------------------------------------------------------------------------ */ /* Function: frpr_icmp */ /* Returns: void */ /* Parameters: fin(I) - pointer to packet information */ /* */ /* IPv4 Only */ /* Do a sanity check on the packet for ICMP (v4). In nearly all cases, */ /* except extrememly bad packets, both type and code will be present. */ /* The expected minimum size of an ICMP packet is very much dependent on */ /* the type of it. */ /* */ /* XXX - other ICMP sanity checks? */ /* ------------------------------------------------------------------------ */ static INLINE void frpr_icmp(fin) fr_info_t *fin; { int minicmpsz = sizeof(struct icmp); icmphdr_t *icmp; ip_t *oip; if (fin->fin_off != 0) { frpr_short(fin, ICMPERR_ICMPHLEN); return; } if (frpr_pullup(fin, ICMPERR_ICMPHLEN) == -1) return; if (fin->fin_dlen > 1) { icmp = fin->fin_dp; fin->fin_data[0] = *(u_short *)icmp; if (fin->fin_dlen >= 6) /* ID field */ fin->fin_data[1] = icmp->icmp_id; switch (icmp->icmp_type) { case ICMP_ECHOREPLY : case ICMP_ECHO : /* Router discovery messaes - RFC 1256 */ case ICMP_ROUTERADVERT : case ICMP_ROUTERSOLICIT : minicmpsz = ICMP_MINLEN; break; /* * type(1) + code(1) + cksum(2) + id(2) seq(2) + * 3 * timestamp(3 * 4) */ case ICMP_TSTAMP : case ICMP_TSTAMPREPLY : minicmpsz = 20; break; /* * type(1) + code(1) + cksum(2) + id(2) seq(2) + * mask(4) */ case ICMP_MASKREQ : case ICMP_MASKREPLY : minicmpsz = 12; break; /* * type(1) + code(1) + cksum(2) + id(2) seq(2) + ip(20+) */ case ICMP_UNREACH : #ifdef icmp_nextmtu if (icmp->icmp_code == ICMP_UNREACH_NEEDFRAG) { if (icmp->icmp_nextmtu < fr_icmpminfragmtu) fin->fin_flx |= FI_BAD; } #endif case ICMP_SOURCEQUENCH : case ICMP_REDIRECT : case ICMP_TIMXCEED : case ICMP_PARAMPROB : fin->fin_flx |= FI_ICMPERR; if (fr_coalesce(fin) != 1) return; /* * ICMP error packets should not be generated for IP * packets that are a fragment that isn't the first * fragment. */ oip = (ip_t *)((char *)fin->fin_dp + ICMPERR_ICMPHLEN); if ((ntohs(oip->ip_off) & IP_OFFMASK) != 0) fin->fin_flx |= FI_BAD; /* * If the destination of this packet doesn't match the * source of the original packet then this packet is * not correct. */ if (oip->ip_src.s_addr != fin->fin_daddr) fin->fin_flx |= FI_BAD; /* * If the destination of this packet doesn't match the * source of the original packet then this packet is * not correct. */ if (oip->ip_src.s_addr != fin->fin_daddr) fin->fin_flx |= FI_BAD; break; default : break; } } frpr_short(fin, minicmpsz); if ((fin->fin_flx & FI_FRAG) == 0) fr_checkv4sum(fin); } /* ------------------------------------------------------------------------ */ /* Function: frpr_tcpcommon */ /* Returns: int - 0 = header ok, 1 = bad packet, -1 = buffer error */ /* Parameters: fin(I) - pointer to packet information */ /* */ /* TCP header sanity checking. Look for bad combinations of TCP flags, */ /* and make some checks with how they interact with other fields. */ /* If compiled with IPFILTER_CKSUM, check to see if the TCP checksum is */ /* valid and mark the packet as bad if not. */ /* ------------------------------------------------------------------------ */ static INLINE int frpr_tcpcommon(fin) fr_info_t *fin; { int flags, tlen; tcphdr_t *tcp; fin->fin_flx |= FI_TCPUDP; if (fin->fin_off != 0) return 0; if (frpr_pullup(fin, sizeof(*tcp)) == -1) return -1; tcp = fin->fin_dp; if (fin->fin_dlen > 3) { fin->fin_sport = ntohs(tcp->th_sport); fin->fin_dport = ntohs(tcp->th_dport); } if ((fin->fin_flx & FI_SHORT) != 0) return 1; /* * Use of the TCP data offset *must* result in a value that is at * least the same size as the TCP header. */ tlen = TCP_OFF(tcp) << 2; if (tlen < sizeof(tcphdr_t)) { fin->fin_flx |= FI_BAD; return 1; } flags = tcp->th_flags; fin->fin_tcpf = tcp->th_flags; /* * If the urgent flag is set, then the urgent pointer must * also be set and vice versa. Good TCP packets do not have * just one of these set. */ if ((flags & TH_URG) != 0 && (tcp->th_urp == 0)) { fin->fin_flx |= FI_BAD; #if 0 } else if ((flags & TH_URG) == 0 && (tcp->th_urp != 0)) { /* * Ignore this case (#if 0) as it shows up in "real" * traffic with bogus values in the urgent pointer field. */ fin->fin_flx |= FI_BAD; #endif } else if (((flags & (TH_SYN|TH_FIN)) != 0) && ((flags & (TH_RST|TH_ACK)) == TH_RST)) { /* TH_FIN|TH_RST|TH_ACK seems to appear "naturally" */ fin->fin_flx |= FI_BAD; #if 1 } else if (((flags & TH_SYN) != 0) && ((flags & (TH_URG|TH_PUSH)) != 0)) { /* * SYN with URG and PUSH set is not for normal TCP but it is * possible(?) with T/TCP...but who uses T/TCP? */ fin->fin_flx |= FI_BAD; #endif } else if (!(flags & TH_ACK)) { /* * If the ack bit isn't set, then either the SYN or * RST bit must be set. If the SYN bit is set, then * we expect the ACK field to be 0. If the ACK is * not set and if URG, PSH or FIN are set, consdier * that to indicate a bad TCP packet. */ if ((flags == TH_SYN) && (tcp->th_ack != 0)) { /* * Cisco PIX sets the ACK field to a random value. * In light of this, do not set FI_BAD until a patch * is available from Cisco to ensure that * interoperability between existing systems is * achieved. */ /*fin->fin_flx |= FI_BAD*/; } else if (!(flags & (TH_RST|TH_SYN))) { fin->fin_flx |= FI_BAD; } else if ((flags & (TH_URG|TH_PUSH|TH_FIN)) != 0) { fin->fin_flx |= FI_BAD; } } /* * At this point, it's not exactly clear what is to be gained by * marking up which TCP options are and are not present. The one we * are most interested in is the TCP window scale. This is only in * a SYN packet [RFC1323] so we don't need this here...? * Now if we were to analyse the header for passive fingerprinting, * then that might add some weight to adding this... */ if (tlen == sizeof(tcphdr_t)) return 0; if (frpr_pullup(fin, tlen) == -1) return -1; #if 0 tcp = fin->fin_dp; ip = fin->fin_ip; s = (u_char *)(tcp + 1); off = IP_HL(ip) << 2; # ifdef _KERNEL if (fin->fin_mp != NULL) { mb_t *m = *fin->fin_mp; if (off + tlen > M_LEN(m)) return; } # endif for (tlen -= (int)sizeof(*tcp); tlen > 0; ) { opt = *s; if (opt == '\0') break; else if (opt == TCPOPT_NOP) ol = 1; else { if (tlen < 2) break; ol = (int)*(s + 1); if (ol < 2 || ol > tlen) break; } for (i = 9, mv = 4; mv >= 0; ) { op = ipopts + i; if (opt == (u_char)op->ol_val) { optmsk |= op->ol_bit; break; } } tlen -= ol; s += ol; } #endif /* 0 */ return 0; } /* ------------------------------------------------------------------------ */ /* Function: frpr_udpcommon */ /* Returns: int - 0 = header ok, 1 = bad packet */ /* Parameters: fin(I) - pointer to packet information */ /* */ /* Extract the UDP source and destination ports, if present. If compiled */ /* with IPFILTER_CKSUM, check to see if the UDP checksum is valid. */ /* ------------------------------------------------------------------------ */ static INLINE int frpr_udpcommon(fin) fr_info_t *fin; { udphdr_t *udp; fin->fin_flx |= FI_TCPUDP; if (!fin->fin_off && (fin->fin_dlen > 3)) { if (frpr_pullup(fin, sizeof(*udp)) == -1) { fin->fin_flx |= FI_SHORT; return 1; } udp = fin->fin_dp; fin->fin_sport = ntohs(udp->uh_sport); fin->fin_dport = ntohs(udp->uh_dport); } return 0; } /* ------------------------------------------------------------------------ */ /* Function: frpr_tcp */ /* Returns: void */ /* Parameters: fin(I) - pointer to packet information */ /* */ /* IPv4 Only */ /* Analyse the packet for IPv4/TCP properties. */ /* ------------------------------------------------------------------------ */ static INLINE void frpr_tcp(fin) fr_info_t *fin; { frpr_short(fin, sizeof(tcphdr_t)); if (frpr_tcpcommon(fin) == 0) { if ((fin->fin_flx & FI_FRAG) == 0) fr_checkv4sum(fin); } } /* ------------------------------------------------------------------------ */ /* Function: frpr_udp */ /* Returns: void */ /* Parameters: fin(I) - pointer to packet information */ /* */ /* IPv4 Only */ /* Analyse the packet for IPv4/UDP properties. */ /* ------------------------------------------------------------------------ */ static INLINE void frpr_udp(fin) fr_info_t *fin; { frpr_short(fin, sizeof(udphdr_t)); if (frpr_udpcommon(fin) == 0) { if ((fin->fin_flx & FI_FRAG) == 0) fr_checkv4sum(fin); } } /* ------------------------------------------------------------------------ */ /* Function: frpr_esp */ /* Returns: void */ /* Parameters: fin(I) - pointer to packet information */ /* */ /* Analyse the packet for ESP properties. */ /* The minimum length is taken to be the SPI (32bits) plus a tail (32bits) */ /* even though the newer ESP packets must also have a sequence number that */ /* is 32bits as well, it is not possible(?) to determine the version from a */ /* simple packet header. */ /* ------------------------------------------------------------------------ */ static INLINE void frpr_esp(fin) fr_info_t *fin; { if (fin->fin_off == 0) { frpr_short(fin, 8); (void) frpr_pullup(fin, 8); } } /* ------------------------------------------------------------------------ */ /* Function: frpr_ah */ /* Returns: void */ /* Parameters: fin(I) - pointer to packet information */ /* */ /* Analyse the packet for AH properties. */ /* The minimum length is taken to be the combination of all fields in the */ /* header being present and no authentication data (null algorithm used.) */ /* ------------------------------------------------------------------------ */ static INLINE void frpr_ah(fin) fr_info_t *fin; { authhdr_t *ah; int len; frpr_short(fin, sizeof(*ah)); if (((fin->fin_flx & FI_SHORT) != 0) || (fin->fin_off != 0)) return; if (frpr_pullup(fin, sizeof(*ah)) == -1) return; ah = (authhdr_t *)fin->fin_dp; len = (ah->ah_plen + 2) << 2; frpr_short(fin, len); } /* ------------------------------------------------------------------------ */ /* Function: frpr_gre */ /* Returns: void */ /* Parameters: fin(I) - pointer to packet information */ /* */ /* Analyse the packet for GRE properties. */ /* ------------------------------------------------------------------------ */ static INLINE void frpr_gre(fin) fr_info_t *fin; { grehdr_t *gre; frpr_short(fin, sizeof(*gre)); if (fin->fin_off != 0) return; if (frpr_pullup(fin, sizeof(*gre)) == -1) return; if (fin->fin_off == 0) { gre = fin->fin_dp; if (GRE_REV(gre->gr_flags) == 1) fin->fin_data[0] = gre->gr_call; } } /* ------------------------------------------------------------------------ */ /* Function: frpr_ipv4hdr */ /* Returns: void */ /* Parameters: fin(I) - pointer to packet information */ /* */ /* IPv4 Only */ /* Analyze the IPv4 header and set fields in the fr_info_t structure. */ /* Check all options present and flag their presence if any exist. */ /* ------------------------------------------------------------------------ */ static INLINE void frpr_ipv4hdr(fin) fr_info_t *fin; { u_short optmsk = 0, secmsk = 0, auth = 0; int hlen, ol, mv, p, i; const struct optlist *op; u_char *s, opt; u_short off; fr_ip_t *fi; ip_t *ip; fi = &fin->fin_fi; hlen = fin->fin_hlen; ip = fin->fin_ip; p = ip->ip_p; fi->fi_p = p; fi->fi_tos = ip->ip_tos; fin->fin_id = ip->ip_id; off = ip->ip_off; /* Get both TTL and protocol */ fi->fi_p = ip->ip_p; fi->fi_ttl = ip->ip_ttl; #if 0 (*(((u_short *)fi) + 1)) = (*(((u_short *)ip) + 4)); #endif /* Zero out bits not used in IPv6 address */ fi->fi_src.i6[1] = 0; fi->fi_src.i6[2] = 0; fi->fi_src.i6[3] = 0; fi->fi_dst.i6[1] = 0; fi->fi_dst.i6[2] = 0; fi->fi_dst.i6[3] = 0; fi->fi_saddr = ip->ip_src.s_addr; fi->fi_daddr = ip->ip_dst.s_addr; /* * set packet attribute flags based on the offset and * calculate the byte offset that it represents. */ off &= IP_MF|IP_OFFMASK; if (off != 0) { int morefrag = off & IP_MF; fi->fi_flx |= FI_FRAG; off &= IP_OFFMASK; if (off != 0) { fin->fin_flx |= FI_FRAGBODY; off <<= 3; if ((off + fin->fin_dlen > 65535) || (fin->fin_dlen == 0) || ((morefrag != 0) && ((fin->fin_dlen & 7) != 0))) { /* * The length of the packet, starting at its * offset cannot exceed 65535 (0xffff) as the * length of an IP packet is only 16 bits. * * Any fragment that isn't the last fragment * must have a length greater than 0 and it * must be an even multiple of 8. */ fi->fi_flx |= FI_BAD; } } } fin->fin_off = off; /* * Call per-protocol setup and checking */ switch (p) { case IPPROTO_UDP : frpr_udp(fin); break; case IPPROTO_TCP : frpr_tcp(fin); break; case IPPROTO_ICMP : frpr_icmp(fin); break; case IPPROTO_AH : frpr_ah(fin); break; case IPPROTO_ESP : frpr_esp(fin); break; case IPPROTO_GRE : frpr_gre(fin); break; } ip = fin->fin_ip; if (ip == NULL) return; /* * If it is a standard IP header (no options), set the flag fields * which relate to options to 0. */ if (hlen == sizeof(*ip)) { fi->fi_optmsk = 0; fi->fi_secmsk = 0; fi->fi_auth = 0; return; } /* * So the IP header has some IP options attached. Walk the entire * list of options present with this packet and set flags to indicate * which ones are here and which ones are not. For the somewhat out * of date and obscure security classification options, set a flag to * represent which classification is present. */ fi->fi_flx |= FI_OPTIONS; for (s = (u_char *)(ip + 1), hlen -= (int)sizeof(*ip); hlen > 0; ) { opt = *s; if (opt == '\0') break; else if (opt == IPOPT_NOP) ol = 1; else { if (hlen < 2) break; ol = (int)*(s + 1); if (ol < 2 || ol > hlen) break; } for (i = 9, mv = 4; mv >= 0; ) { op = ipopts + i; if ((opt == (u_char)op->ol_val) && (ol > 4)) { optmsk |= op->ol_bit; if (opt == IPOPT_SECURITY) { const struct optlist *sp; u_char sec; int j, m; sec = *(s + 2); /* classification */ for (j = 3, m = 2; m >= 0; ) { sp = secopt + j; if (sec == sp->ol_val) { secmsk |= sp->ol_bit; auth = *(s + 3); auth *= 256; auth += *(s + 4); break; } if (sec < sp->ol_val) j -= m; else j += m; m--; } } break; } if (opt < op->ol_val) i -= mv; else i += mv; mv--; } hlen -= ol; s += ol; } /* * */ if (auth && !(auth & 0x0100)) auth &= 0xff00; fi->fi_optmsk = optmsk; fi->fi_secmsk = secmsk; fi->fi_auth = auth; } /* ------------------------------------------------------------------------ */ /* Function: fr_makefrip */ /* Returns: void */ /* Parameters: hlen(I) - length of IP packet header */ /* ip(I) - pointer to the IP header */ /* fin(IO) - pointer to packet information */ /* */ /* Compact the IP header into a structure which contains just the info. */ /* which is useful for comparing IP headers with and store this information */ /* in the fr_info_t structure pointer to by fin. At present, it is assumed */ /* this function will be called with either an IPv4 or IPv6 packet. */ /* ------------------------------------------------------------------------ */ int fr_makefrip(hlen, ip, fin) int hlen; ip_t *ip; fr_info_t *fin; { int v; fin->fin_nat = NULL; fin->fin_state = NULL; fin->fin_depth = 0; fin->fin_hlen = (u_short)hlen; fin->fin_ip = ip; fin->fin_rule = 0xffffffff; fin->fin_group[0] = -1; fin->fin_group[1] = '\0'; fin->fin_dp = (char *)ip + hlen; v = fin->fin_v; if (v == 4) { fin->fin_plen = ip->ip_len; fin->fin_dlen = fin->fin_plen - hlen; frpr_ipv4hdr(fin); #ifdef USE_INET6 } else if (v == 6) { fin->fin_plen = ntohs(((ip6_t *)ip)->ip6_plen); fin->fin_dlen = fin->fin_plen; fin->fin_plen += hlen; if (frpr_ipv6hdr(fin) == -1) return -1; #endif } if (fin->fin_ip == NULL) return -1; return 0; } /* ------------------------------------------------------------------------ */ /* Function: fr_portcheck */ /* Returns: int - 1 == port matched, 0 == port match failed */ /* Parameters: frp(I) - pointer to port check `expression' */ /* pop(I) - pointer to port number to evaluate */ /* */ /* Perform a comparison of a port number against some other(s), using a */ /* structure with compare information stored in it. */ /* ------------------------------------------------------------------------ */ static INLINE int fr_portcheck(frp, pop) frpcmp_t *frp; u_short *pop; { u_short tup, po; int err = 1; tup = *pop; po = frp->frp_port; /* * Do opposite test to that required and continue if that succeeds. */ switch (frp->frp_cmp) { case FR_EQUAL : if (tup != po) /* EQUAL */ err = 0; break; case FR_NEQUAL : if (tup == po) /* NOTEQUAL */ err = 0; break; case FR_LESST : if (tup >= po) /* LESSTHAN */ err = 0; break; case FR_GREATERT : if (tup <= po) /* GREATERTHAN */ err = 0; break; case FR_LESSTE : if (tup > po) /* LT or EQ */ err = 0; break; case FR_GREATERTE : if (tup < po) /* GT or EQ */ err = 0; break; case FR_OUTRANGE : if (tup >= po && tup <= frp->frp_top) /* Out of range */ err = 0; break; case FR_INRANGE : if (tup <= po || tup >= frp->frp_top) /* In range */ err = 0; break; case FR_INCRANGE : if (tup < po || tup > frp->frp_top) /* Inclusive range */ err = 0; break; default : break; } return err; } /* ------------------------------------------------------------------------ */ /* Function: fr_tcpudpchk */ /* Returns: int - 1 == protocol matched, 0 == check failed */ /* Parameters: fin(I) - pointer to packet information */ /* ft(I) - pointer to structure with comparison data */ /* */ /* Compares the current pcket (assuming it is TCP/UDP) information with a */ /* structure containing information that we want to match against. */ /* ------------------------------------------------------------------------ */ int fr_tcpudpchk(fin, ft) fr_info_t *fin; frtuc_t *ft; { int err = 1; /* * Both ports should *always* be in the first fragment. * So far, I cannot find any cases where they can not be. * * compare destination ports */ if (ft->ftu_dcmp) err = fr_portcheck(&ft->ftu_dst, &fin->fin_dport); /* * compare source ports */ if (err && ft->ftu_scmp) err = fr_portcheck(&ft->ftu_src, &fin->fin_sport); /* * If we don't have all the TCP/UDP header, then how can we * expect to do any sort of match on it ? If we were looking for * TCP flags, then NO match. If not, then match (which should * satisfy the "short" class too). */ if (err && (fin->fin_p == IPPROTO_TCP)) { if (fin->fin_flx & FI_SHORT) return !(ft->ftu_tcpf | ft->ftu_tcpfm); /* * Match the flags ? If not, abort this match. */ if (ft->ftu_tcpfm && ft->ftu_tcpf != (fin->fin_tcpf & ft->ftu_tcpfm)) { FR_DEBUG(("f. %#x & %#x != %#x\n", fin->fin_tcpf, ft->ftu_tcpfm, ft->ftu_tcpf)); err = 0; } } return err; } /* ------------------------------------------------------------------------ */ /* Function: fr_ipfcheck */ /* Returns: int - 0 == match, 1 == no match */ /* Parameters: fin(I) - pointer to packet information */ /* fr(I) - pointer to filter rule */ /* portcmp(I) - flag indicating whether to attempt matching on */ /* TCP/UDP port data. */ /* */ /* Check to see if a packet matches an IPFilter rule. Checks of addresses, */ /* port numbers, etc, for "standard" IPFilter rules are all orchestrated in */ /* this function. */ /* ------------------------------------------------------------------------ */ static INLINE int fr_ipfcheck(fin, fr, portcmp) fr_info_t *fin; frentry_t *fr; int portcmp; { u_32_t *ld, *lm, *lip; fripf_t *fri; fr_ip_t *fi; int i; fi = &fin->fin_fi; fri = fr->fr_ipf; lip = (u_32_t *)fi; lm = (u_32_t *)&fri->fri_mip; ld = (u_32_t *)&fri->fri_ip; /* * first 32 bits to check coversion: * IP version, TOS, TTL, protocol */ i = ((*lip & *lm) != *ld); FR_DEBUG(("0. %#08x & %#08x != %#08x\n", ntohl(*lip), ntohl(*lm), ntohl(*ld))); if (i) return 1; /* * Next 32 bits is a constructed bitmask indicating which IP options * are present (if any) in this packet. */ lip++, lm++, ld++; i |= ((*lip & *lm) != *ld); FR_DEBUG(("1. %#08x & %#08x != %#08x\n", ntohl(*lip), ntohl(*lm), ntohl(*ld))); if (i) return 1; lip++, lm++, ld++; /* * Unrolled loops (4 each, for 32 bits) for address checks. */ /* * Check the source address. */ #ifdef IPFILTER_LOOKUP if (fr->fr_satype == FRI_LOOKUP) { i = (*fr->fr_srcfunc)(fr->fr_srcptr, fi->fi_v, lip); if (i == -1) return 1; lip += 3; lm += 3; ld += 3; } else { #endif i = ((*lip & *lm) != *ld); FR_DEBUG(("2a. %#08x & %#08x != %#08x\n", ntohl(*lip), ntohl(*lm), ntohl(*ld))); if (fi->fi_v == 6) { lip++, lm++, ld++; i |= ((*lip & *lm) != *ld); FR_DEBUG(("2b. %#08x & %#08x != %#08x\n", ntohl(*lip), ntohl(*lm), ntohl(*ld))); lip++, lm++, ld++; i |= ((*lip & *lm) != *ld); FR_DEBUG(("2c. %#08x & %#08x != %#08x\n", ntohl(*lip), ntohl(*lm), ntohl(*ld))); lip++, lm++, ld++; i |= ((*lip & *lm) != *ld); FR_DEBUG(("2d. %#08x & %#08x != %#08x\n", ntohl(*lip), ntohl(*lm), ntohl(*ld))); } else { lip += 3; lm += 3; ld += 3; } #ifdef IPFILTER_LOOKUP } #endif i ^= (fr->fr_flags & FR_NOTSRCIP) >> 6; if (i) return 1; /* * Check the destination address. */ lip++, lm++, ld++; #ifdef IPFILTER_LOOKUP if (fr->fr_datype == FRI_LOOKUP) { i = (*fr->fr_dstfunc)(fr->fr_dstptr, fi->fi_v, lip); if (i == -1) return 1; lip += 3; lm += 3; ld += 3; } else { #endif i = ((*lip & *lm) != *ld); FR_DEBUG(("3a. %#08x & %#08x != %#08x\n", ntohl(*lip), ntohl(*lm), ntohl(*ld))); if (fi->fi_v == 6) { lip++, lm++, ld++; i |= ((*lip & *lm) != *ld); FR_DEBUG(("3b. %#08x & %#08x != %#08x\n", ntohl(*lip), ntohl(*lm), ntohl(*ld))); lip++, lm++, ld++; i |= ((*lip & *lm) != *ld); FR_DEBUG(("3c. %#08x & %#08x != %#08x\n", ntohl(*lip), ntohl(*lm), ntohl(*ld))); lip++, lm++, ld++; i |= ((*lip & *lm) != *ld); FR_DEBUG(("3d. %#08x & %#08x != %#08x\n", ntohl(*lip), ntohl(*lm), ntohl(*ld))); } else { lip += 3; lm += 3; ld += 3; } #ifdef IPFILTER_LOOKUP } #endif i ^= (fr->fr_flags & FR_NOTDSTIP) >> 7; if (i) return 1; /* * IP addresses matched. The next 32bits contains: * mast of old IP header security & authentication bits. */ lip++, lm++, ld++; i |= ((*lip & *lm) != *ld); FR_DEBUG(("4. %#08x & %#08x != %#08x\n", *lip, *lm, *ld)); /* * Next we have 32 bits of packet flags. */ lip++, lm++, ld++; i |= ((*lip & *lm) != *ld); FR_DEBUG(("5. %#08x & %#08x != %#08x\n", *lip, *lm, *ld)); if (i == 0) { /* * If a fragment, then only the first has what we're * looking for here... */ if (portcmp) { if (!fr_tcpudpchk(fin, &fr->fr_tuc)) i = 1; } else { if (fr->fr_dcmp || fr->fr_scmp || fr->fr_tcpf || fr->fr_tcpfm) i = 1; if (fr->fr_icmpm || fr->fr_icmp) { if (((fi->fi_p != IPPROTO_ICMP) && (fi->fi_p != IPPROTO_ICMPV6)) || fin->fin_off || (fin->fin_dlen < 2)) i = 1; else if ((fin->fin_data[0] & fr->fr_icmpm) != fr->fr_icmp) { FR_DEBUG(("i. %#x & %#x != %#x\n", fin->fin_data[0], fr->fr_icmpm, fr->fr_icmp)); i = 1; } } } } return i; } /* ------------------------------------------------------------------------ */ /* Function: fr_scanlist */ /* Returns: int - result flags of scanning filter list */ /* Parameters: fin(I) - pointer to packet information */ /* pass(I) - default result to return for filtering */ /* */ /* Check the input/output list of rules for a match to the current packet. */ /* If a match is found, the value of fr_flags from the rule becomes the */ /* return value and fin->fin_fr points to the matched rule. */ /* */ /* This function may be called recusively upto 16 times (limit inbuilt.) */ /* When unwinding, it should finish up with fin_depth as 0. */ /* */ /* Could be per interface, but this gets real nasty when you don't have, */ /* or can't easily change, the kernel source code to . */ /* ------------------------------------------------------------------------ */ int fr_scanlist(fin, pass) fr_info_t *fin; u_32_t pass; { int rulen, portcmp, off, skip; struct frentry *fr, *fnext; u_32_t passt, passo; /* * Do not allow nesting deeper than 16 levels. */ if (fin->fin_depth >= 16) return pass; fr = fin->fin_fr; /* * If there are no rules in this list, return now. */ if (fr == NULL) return pass; skip = 0; portcmp = 0; fin->fin_depth++; fin->fin_fr = NULL; off = fin->fin_off; if ((fin->fin_flx & FI_TCPUDP) && (fin->fin_dlen > 3) && !off) portcmp = 1; for (rulen = 0; fr; fr = fnext, rulen++) { fnext = fr->fr_next; if (skip != 0) { FR_VERBOSE(("%d (%#x)\n", skip, fr->fr_flags)); skip--; continue; } /* * In all checks below, a null (zero) value in the * filter struture is taken to mean a wildcard. * * check that we are working for the right interface */ #ifdef _KERNEL if (fr->fr_ifa && fr->fr_ifa != fin->fin_ifp) continue; #else if (opts & (OPT_VERBOSE|OPT_DEBUG)) printf("\n"); FR_VERBOSE(("%c", FR_ISSKIP(pass) ? 's' : FR_ISPASS(pass) ? 'p' : FR_ISACCOUNT(pass) ? 'A' : FR_ISAUTH(pass) ? 'a' : (pass & FR_NOMATCH) ? 'n' :'b')); if (fr->fr_ifa && fr->fr_ifa != fin->fin_ifp) continue; FR_VERBOSE((":i")); #endif switch (fr->fr_type) { case FR_T_IPF : case FR_T_IPF|FR_T_BUILTIN : if (fr_ipfcheck(fin, fr, portcmp)) continue; break; #if defined(IPFILTER_BPF) case FR_T_BPFOPC : case FR_T_BPFOPC|FR_T_BUILTIN : { u_char *mc; if (*fin->fin_mp == NULL) continue; if (fin->fin_v != fr->fr_v) continue; mc = (u_char *)fin->fin_m; if (!bpf_filter(fr->fr_data, mc, fin->fin_plen, 0)) continue; break; } #endif case FR_T_CALLFUNC|FR_T_BUILTIN : { frentry_t *f; f = (*fr->fr_func)(fin, &pass); if (f != NULL) fr = f; else continue; break; } default : break; } if ((fin->fin_out == 0) && (fr->fr_nattag.ipt_num[0] != 0)) { if (fin->fin_nattag == NULL) continue; if (fr_matchtag(&fr->fr_nattag, fin->fin_nattag) == 0) continue; } FR_VERBOSE(("=%s.%d *", fr->fr_group, rulen)); passt = fr->fr_flags; /* * Allowing a rule with the "keep state" flag set to match * packets that have been tagged "out of window" by the TCP * state tracking is foolish as the attempt to add a new * state entry to the table will fail. */ if ((passt & FR_KEEPSTATE) && (fin->fin_flx & FI_OOW)) continue; /* * If the rule is a "call now" rule, then call the function * in the rule, if it exists and use the results from that. * If the function pointer is bad, just make like we ignore * it, except for increasing the hit counter. */ if ((passt & FR_CALLNOW) != 0) { frentry_t *frs; ATOMIC_INC64(fr->fr_hits); if ((fr->fr_func != NULL) && (fr->fr_func == (ipfunc_t)-1)) continue; frs = fin->fin_fr; fin->fin_fr = fr; fr = (*fr->fr_func)(fin, &passt); if (fr == NULL) { fin->fin_fr = frs; continue; } passt = fr->fr_flags; } fin->fin_fr = fr; #ifdef IPFILTER_LOG /* * Just log this packet... */ if ((passt & FR_LOGMASK) == FR_LOG) { if (ipflog(fin, passt) == -1) { if (passt & FR_LOGORBLOCK) { passt &= ~FR_CMDMASK; passt |= FR_BLOCK|FR_QUICK; } ATOMIC_INCL(frstats[fin->fin_out].fr_skip); } ATOMIC_INCL(frstats[fin->fin_out].fr_pkl); fin->fin_flx |= FI_DONTCACHE; } #endif /* IPFILTER_LOG */ fr->fr_bytes += (U_QUAD_T)fin->fin_plen; passo = pass; if (FR_ISSKIP(passt)) skip = fr->fr_arg; else if ((passt & FR_LOGMASK) != FR_LOG) pass = passt; if (passt & (FR_RETICMP|FR_FAKEICMP)) fin->fin_icode = fr->fr_icode; FR_DEBUG(("pass %#x\n", pass)); ATOMIC_INC64(fr->fr_hits); fin->fin_rule = rulen; (void) strncpy(fin->fin_group, fr->fr_group, FR_GROUPLEN); if (fr->fr_grp != NULL) { fin->fin_fr = *fr->fr_grp; passt = fr_scanlist(fin, pass); if (fin->fin_fr == NULL) { fin->fin_rule = rulen; (void) strncpy(fin->fin_group, fr->fr_group, FR_GROUPLEN); fin->fin_fr = fr; passt = pass; } pass = passt; } if (passt & FR_QUICK) { /* * Finally, if we've asked to track state for this * packet, set it up. Add state for "quick" rules * here so that if the action fails we can consider * the rule to "not match" and keep on processing * filter rules. */ if ((pass & FR_KEEPSTATE) && !(fin->fin_flx & FI_STATE)) { int out = fin->fin_out; fin->fin_fr = fr; if (fr_addstate(fin, NULL, 0) != NULL) { ATOMIC_INCL(frstats[out].fr_ads); } else { ATOMIC_INCL(frstats[out].fr_bads); pass = passo; continue; } } break; } } fin->fin_depth--; return pass; } /* ------------------------------------------------------------------------ */ /* Function: fr_acctpkt */ /* Returns: frentry_t* - always returns NULL */ /* Parameters: fin(I) - pointer to packet information */ /* passp(IO) - pointer to current/new filter decision (unused) */ /* */ /* Checks a packet against accounting rules, if there are any for the given */ /* IP protocol version. */ /* */ /* N.B.: this function returns NULL to match the prototype used by other */ /* functions called from the IPFilter "mainline" in fr_check(). */ /* ------------------------------------------------------------------------ */ frentry_t *fr_acctpkt(fin, passp) fr_info_t *fin; u_32_t *passp; { char group[FR_GROUPLEN]; frentry_t *fr, *frsave; u_32_t pass, rulen; passp = passp; #ifdef USE_INET6 if (fin->fin_v == 6) fr = ipacct6[fin->fin_out][fr_active]; else #endif fr = ipacct[fin->fin_out][fr_active]; if (fr != NULL) { frsave = fin->fin_fr; bcopy(fin->fin_group, group, FR_GROUPLEN); rulen = fin->fin_rule; fin->fin_fr = fr; pass = fr_scanlist(fin, FR_NOMATCH); if (FR_ISACCOUNT(pass)) { ATOMIC_INCL(frstats[0].fr_acct); } fin->fin_fr = frsave; bcopy(group, fin->fin_group, FR_GROUPLEN); fin->fin_rule = rulen; } return NULL; } /* ------------------------------------------------------------------------ */ /* Function: fr_firewall */ /* Returns: frentry_t* - returns pointer to matched rule, if no matches */ /* were found, returns NULL. */ /* Parameters: fin(I) - pointer to packet information */ /* passp(IO) - pointer to current/new filter decision (unused) */ /* */ /* Applies an appropriate set of firewall rules to the packet, to see if */ /* there are any matches. The first check is to see if a match can be seen */ /* in the cache. If not, then search an appropriate list of rules. Once a */ /* matching rule is found, take any appropriate actions as defined by the */ /* rule - except logging. */ /* ------------------------------------------------------------------------ */ static frentry_t *fr_firewall(fin, passp) fr_info_t *fin; u_32_t *passp; { frentry_t *fr; fr_info_t *fc; u_32_t pass; int out; out = fin->fin_out; pass = *passp; /* * If a packet is found in the auth table, then skip checking * the access lists for permission but we do need to consider * the result as if it were from the ACL's. */ fc = &frcache[out][CACHE_HASH(fin)]; READ_ENTER(&ipf_frcache); if (!bcmp((char *)fin, (char *)fc, FI_CSIZE)) { /* * copy cached data so we can unlock the mutexes earlier. */ bcopy((char *)fc, (char *)fin, FI_COPYSIZE); RWLOCK_EXIT(&ipf_frcache); ATOMIC_INCL(frstats[out].fr_chit); if ((fr = fin->fin_fr) != NULL) { ATOMIC_INC64(fr->fr_hits); pass = fr->fr_flags; } } else { RWLOCK_EXIT(&ipf_frcache); #ifdef USE_INET6 if (fin->fin_v == 6) fin->fin_fr = ipfilter6[out][fr_active]; else #endif fin->fin_fr = ipfilter[out][fr_active]; if (fin->fin_fr != NULL) pass = fr_scanlist(fin, fr_pass); if (((pass & FR_KEEPSTATE) == 0) && ((fin->fin_flx & FI_DONTCACHE) == 0)) { WRITE_ENTER(&ipf_frcache); bcopy((char *)fin, (char *)fc, FI_COPYSIZE); RWLOCK_EXIT(&ipf_frcache); } if ((pass & FR_NOMATCH)) { ATOMIC_INCL(frstats[out].fr_nom); } fr = fin->fin_fr; } /* * Apply packets per second rate-limiting to a rule as required. */ if ((fr != NULL) && (fr->fr_pps != 0) && !ppsratecheck(&fr->fr_lastpkt, &fr->fr_curpps, fr->fr_pps)) { pass &= ~(FR_CMDMASK|FR_DUP|FR_RETICMP|FR_RETRST); pass |= FR_BLOCK; ATOMIC_INCL(frstats[out].fr_ppshit); } /* * If we fail to add a packet to the authorization queue, then we * drop the packet later. However, if it was added then pretend * we've dropped it already. */ if (FR_ISAUTH(pass)) { if (fr_newauth(fin->fin_m, fin) != 0) { #ifdef _KERNEL fin->fin_m = *fin->fin_mp = NULL; #else ; #endif fin->fin_error = 0; } else fin->fin_error = ENOSPC; } if ((fr != NULL) && (fr->fr_func != NULL) && (fr->fr_func != (ipfunc_t)-1) && !(pass & FR_CALLNOW)) (void) (*fr->fr_func)(fin, &pass); /* * If a rule is a pre-auth rule, check again in the list of rules * loaded for authenticated use. It does not particulary matter * if this search fails because a "preauth" result, from a rule, * is treated as "not a pass", hence the packet is blocked. */ if (FR_ISPREAUTH(pass)) { if ((fin->fin_fr = ipauth) != NULL) pass = fr_scanlist(fin, fr_pass); } /* * If the rule has "keep frag" and the packet is actually a fragment, * then create a fragment state entry. */ if ((pass & (FR_KEEPFRAG|FR_KEEPSTATE)) == FR_KEEPFRAG) { if (fin->fin_flx & FI_FRAG) { if (fr_newfrag(fin, pass) == -1) { ATOMIC_INCL(frstats[out].fr_bnfr); } else { ATOMIC_INCL(frstats[out].fr_nfr); } } else { ATOMIC_INCL(frstats[out].fr_cfr); } } fr = fin->fin_fr; if (passp != NULL) *passp = pass; return fr; } /* ------------------------------------------------------------------------ */ /* Function: fr_check */ /* Returns: int - 0 == packet allowed through, */ /* User space: */ /* -1 == packet blocked */ /* 1 == packet not matched */ /* -2 == requires authentication */ /* Kernel: */ /* > 0 == filter error # for packet */ /* Parameters: ip(I) - pointer to start of IPv4/6 packet */ /* hlen(I) - length of header */ /* ifp(I) - pointer to interface this packet is on */ /* out(I) - 0 == packet going in, 1 == packet going out */ /* mp(IO) - pointer to caller's buffer pointer that holds this */ /* IP packet. */ /* Solaris & HP-UX ONLY : */ /* qpi(I) - pointer to STREAMS queue information for this */ /* interface & direction. */ /* */ /* fr_check() is the master function for all IPFilter packet processing. */ /* It orchestrates: Network Address Translation (NAT), checking for packet */ /* authorisation (or pre-authorisation), presence of related state info., */ /* generating log entries, IP packet accounting, routing of packets as */ /* directed by firewall rules and of course whether or not to allow the */ /* packet to be further processed by the kernel. */ /* */ /* For packets blocked, the contents of "mp" will be NULL'd and the buffer */ /* freed. Packets passed may be returned with the pointer pointed to by */ /* by "mp" changed to a new buffer. */ /* ------------------------------------------------------------------------ */ int fr_check(ip, hlen, ifp, out #if defined(_KERNEL) && defined(MENTAT) , qif, mp) void *qif; #else , mp) #endif mb_t **mp; ip_t *ip; int hlen; void *ifp; int out; { /* * The above really sucks, but short of writing a diff */ fr_info_t frinfo; fr_info_t *fin = &frinfo; u_32_t pass = fr_pass; frentry_t *fr = NULL; int v = IP_V(ip); mb_t *mc = NULL; mb_t *m; /* * The first part of fr_check() deals with making sure that what goes * into the filtering engine makes some sense. Information about the * the packet is distilled, collected into a fr_info_t structure and * the an attempt to ensure the buffer the packet is in is big enough * to hold all the required packet headers. */ #ifdef _KERNEL # ifdef MENTAT qpktinfo_t *qpi = qif; # if !defined(_INET_IP_STACK_H) if ((u_int)ip & 0x3) return 2; # endif # else SPL_INT(s); # endif READ_ENTER(&ipf_global); if (fr_running <= 0) { RWLOCK_EXIT(&ipf_global); return 0; } bzero((char *)fin, sizeof(*fin)); # ifdef MENTAT if (qpi->qpi_flags & QF_GROUP) fin->fin_flx |= FI_MBCAST; m = qpi->qpi_m; fin->fin_qfm = m; fin->fin_qpi = qpi; # else /* MENTAT */ m = *mp; # if defined(M_MCAST) if ((m->m_flags & M_MCAST) != 0) fin->fin_flx |= FI_MBCAST|FI_MULTICAST; # endif # if defined(M_MLOOP) if ((m->m_flags & M_MLOOP) != 0) fin->fin_flx |= FI_MBCAST|FI_MULTICAST; # endif # if defined(M_BCAST) if ((m->m_flags & M_BCAST) != 0) fin->fin_flx |= FI_MBCAST|FI_BROADCAST; # endif # ifdef M_CANFASTFWD /* * XXX For now, IP Filter and fast-forwarding of cached flows * XXX are mutually exclusive. Eventually, IP Filter should * XXX get a "can-fast-forward" filter rule. */ m->m_flags &= ~M_CANFASTFWD; # endif /* M_CANFASTFWD */ # ifdef CSUM_DELAY_DATA /* * disable delayed checksums. */ if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { in_delayed_cksum(m); m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; } # endif /* CSUM_DELAY_DATA */ # endif /* MENTAT */ #else READ_ENTER(&ipf_global); bzero((char *)fin, sizeof(*fin)); m = *mp; #endif /* _KERNEL */ fin->fin_v = v; fin->fin_m = m; fin->fin_ip = ip; fin->fin_mp = mp; fin->fin_out = out; fin->fin_ifp = ifp; fin->fin_error = ENETUNREACH; fin->fin_hlen = (u_short)hlen; fin->fin_dp = (char *)ip + hlen; fin->fin_ipoff = (char *)ip - MTOD(m, char *); SPL_NET(s); #ifdef USE_INET6 if (v == 6) { ATOMIC_INCL(frstats[out].fr_ipv6); /* * Jumbo grams are quite likely too big for internal buffer * structures to handle comfortably, for now, so just drop * them. */ if (((ip6_t *)ip)->ip6_plen == 0) { pass = FR_BLOCK|FR_NOMATCH; goto finished; } } else #endif { #if (defined(OpenBSD) && OpenBSD >= 200311) && defined(_KERNEL) ip->ip_len = ntohs(ip->ip_len); ip->ip_off = ntohs(ip->ip_off); #endif } if (fr_makefrip(hlen, ip, fin) == -1) { pass = FR_BLOCK|FR_NOMATCH; goto finished; } /* * For at least IPv6 packets, if a m_pullup() fails then this pointer * becomes NULL and so we have no packet to free. */ if (*fin->fin_mp == NULL) goto finished; if (!out) { if (v == 4) { #ifdef _KERNEL if (fr_chksrc && !fr_verifysrc(fin)) { ATOMIC_INCL(frstats[0].fr_badsrc); fin->fin_flx |= FI_BADSRC; } #endif if (fin->fin_ip->ip_ttl < fr_minttl) { ATOMIC_INCL(frstats[0].fr_badttl); fin->fin_flx |= FI_LOWTTL; } } #ifdef USE_INET6 else if (v == 6) { if (((ip6_t *)ip)->ip6_hlim < fr_minttl) { ATOMIC_INCL(frstats[0].fr_badttl); fin->fin_flx |= FI_LOWTTL; } } #endif } if (fin->fin_flx & FI_SHORT) { ATOMIC_INCL(frstats[out].fr_short); } READ_ENTER(&ipf_mutex); /* * Check auth now. This, combined with the check below to see if apass * is 0 is to ensure that we don't count the packet twice, which can * otherwise occur when we reprocess it. As it is, we only count it * after it has no auth. table matchup. This also stops NAT from * occuring until after the packet has been auth'd. */ fr = fr_checkauth(fin, &pass); if (!out) { if (fr_checknatin(fin, &pass) == -1) { goto filterdone; } } if (!out) (void) fr_acctpkt(fin, NULL); if (fr == NULL) { if ((fin->fin_flx & (FI_FRAG|FI_BAD)) == FI_FRAG) { fr = fr_knownfrag(fin, &pass); /* * Reset the keep state flag here so that we don't * try and add a new state entry because of it, leading * to a blocked packet because the add will fail. */ if (fr != NULL) pass &= ~FR_KEEPSTATE; } if (fr == NULL) fr = fr_checkstate(fin, &pass); } if ((pass & FR_NOMATCH) || (fr == NULL)) fr = fr_firewall(fin, &pass); /* * If we've asked to track state for this packet, set it up. * Here rather than fr_firewall because fr_checkauth may decide * to return a packet for "keep state" */ if ((pass & FR_KEEPSTATE) && (fin->fin_m != NULL) && !(fin->fin_flx & FI_STATE)) { if (fr_addstate(fin, NULL, 0) != NULL) { ATOMIC_INCL(frstats[out].fr_ads); } else { ATOMIC_INCL(frstats[out].fr_bads); if (FR_ISPASS(pass)) { pass &= ~FR_CMDMASK; pass |= FR_BLOCK; } } } fin->fin_fr = fr; /* * Only count/translate packets which will be passed on, out the * interface. */ if (out && FR_ISPASS(pass)) { (void) fr_acctpkt(fin, NULL); if (fr_checknatout(fin, &pass) == -1) { ; } else if ((fr_update_ipid != 0) && (v == 4)) { if (fr_updateipid(fin) == -1) { ATOMIC_INCL(frstats[1].fr_ipud); pass &= ~FR_CMDMASK; pass |= FR_BLOCK; } else { ATOMIC_INCL(frstats[0].fr_ipud); } } } filterdone: #ifdef IPFILTER_LOG if ((fr_flags & FF_LOGGING) || (pass & FR_LOGMASK)) { (void) fr_dolog(fin, &pass); } #endif /* * The FI_STATE flag is cleared here so that calling fr_checkstate * will work when called from inside of fr_fastroute. Although * there is a similar flag, FI_NATED, for NAT, it does have the same * impact on code execution. */ if (fin->fin_state != NULL) { fr_statederef((ipstate_t **)&fin->fin_state); fin->fin_flx ^= FI_STATE; } if (fin->fin_nat != NULL) { if (FR_ISBLOCK(pass) && (fin->fin_flx & FI_NEWNAT)) { WRITE_ENTER(&ipf_nat); nat_delete((nat_t *)fin->fin_nat, NL_DESTROY); RWLOCK_EXIT(&ipf_nat); fin->fin_nat = NULL; } else { fr_natderef((nat_t **)&fin->fin_nat); } } /* * Up the reference on fr_lock and exit ipf_mutex. fr_fastroute * only frees up the lock on ipf_global and the generation of a * packet below could cause a recursive call into IPFilter. * Hang onto the filter rule just in case someone decides to remove * or flush it in the meantime. */ if (fr != NULL) { MUTEX_ENTER(&fr->fr_lock); fr->fr_ref++; MUTEX_EXIT(&fr->fr_lock); } RWLOCK_EXIT(&ipf_mutex); if ((pass & FR_RETMASK) != 0) { /* * Should we return an ICMP packet to indicate error * status passing through the packet filter ? * WARNING: ICMP error packets AND TCP RST packets should * ONLY be sent in repsonse to incoming packets. Sending them * in response to outbound packets can result in a panic on * some operating systems. */ if (!out) { if (pass & FR_RETICMP) { int dst; if ((pass & FR_RETMASK) == FR_FAKEICMP) dst = 1; else dst = 0; (void) fr_send_icmp_err(ICMP_UNREACH, fin, dst); ATOMIC_INCL(frstats[0].fr_ret); } else if (((pass & FR_RETMASK) == FR_RETRST) && !(fin->fin_flx & FI_SHORT)) { if (((fin->fin_flx & FI_OOW) != 0) || (fr_send_reset(fin) == 0)) { ATOMIC_INCL(frstats[1].fr_ret); } } /* * When using return-* with auth rules, the auth code * takes over disposing of this packet. */ if (FR_ISAUTH(pass) && (fin->fin_m != NULL)) { fin->fin_m = *fin->fin_mp = NULL; } } else { if (pass & FR_RETRST) fin->fin_error = ECONNRESET; } } /* * If we didn't drop off the bottom of the list of rules (and thus * the 'current' rule fr is not NULL), then we may have some extra * instructions about what to do with a packet. * Once we're finished return to our caller, freeing the packet if * we are dropping it (* BSD ONLY *). */ if (fr != NULL) { frdest_t *fdp; fdp = &fr->fr_tifs[fin->fin_rev]; if (!out && (pass & FR_FASTROUTE)) { /* * For fastroute rule, no destioation interface defined * so pass NULL as the frdest_t parameter */ (void) fr_fastroute(fin->fin_m, mp, fin, NULL); m = *mp = NULL; } else if ((fdp->fd_ifp != NULL) && (fdp->fd_ifp != (struct ifnet *)-1)) { /* this is for to rules: */ (void) fr_fastroute(fin->fin_m, mp, fin, fdp); m = *mp = NULL; } /* * Generate a duplicated packet. */ if ((pass & FR_DUP) != 0) { mc = M_DUPLICATE(fin->fin_m); if (mc != NULL) (void) fr_fastroute(mc, &mc, fin, &fr->fr_dif); } (void) fr_derefrule(&fr); } finished: if (!FR_ISPASS(pass)) { ATOMIC_INCL(frstats[out].fr_block); if (*mp != NULL) { FREE_MB_T(*mp); m = *mp = NULL; } } else { ATOMIC_INCL(frstats[out].fr_pass); #if defined(_KERNEL) && defined(__sgi) if ((fin->fin_hbuf != NULL) && (mtod(fin->fin_m, struct ip *) != fin->fin_ip)) { COPYBACK(fin->fin_m, 0, fin->fin_plen, fin->fin_hbuf); } #endif } SPL_X(s); RWLOCK_EXIT(&ipf_global); #ifdef _KERNEL # if defined(OpenBSD) && OpenBSD >= 200311 if (FR_ISPASS(pass) && (v == 4)) { ip = fin->fin_ip; ip->ip_len = ntohs(ip->ip_len); ip->ip_off = ntohs(ip->ip_off); } # endif return (FR_ISPASS(pass)) ? 0 : fin->fin_error; #else /* _KERNEL */ FR_VERBOSE(("fin_flx %#x pass %#x ", fin->fin_flx, pass)); if ((pass & FR_NOMATCH) != 0) return 1; if ((pass & FR_RETMASK) != 0) switch (pass & FR_RETMASK) { case FR_RETRST : return 3; case FR_RETICMP : return 4; case FR_FAKEICMP : return 5; } switch (pass & FR_CMDMASK) { case FR_PASS : return 0; case FR_BLOCK : return -1; case FR_AUTH : return -2; case FR_ACCOUNT : return -3; case FR_PREAUTH : return -4; } return 2; #endif /* _KERNEL */ } #ifdef IPFILTER_LOG /* ------------------------------------------------------------------------ */ /* Function: fr_dolog */ /* Returns: frentry_t* - returns contents of fin_fr (no change made) */ /* Parameters: fin(I) - pointer to packet information */ /* passp(IO) - pointer to current/new filter decision (unused) */ /* */ /* Checks flags set to see how a packet should be logged, if it is to be */ /* logged. Adjust statistics based on its success or not. */ /* ------------------------------------------------------------------------ */ frentry_t *fr_dolog(fin, passp) fr_info_t *fin; u_32_t *passp; { u_32_t pass; int out; out = fin->fin_out; pass = *passp; if ((fr_flags & FF_LOGNOMATCH) && (pass & FR_NOMATCH)) { pass |= FF_LOGNOMATCH; ATOMIC_INCL(frstats[out].fr_npkl); goto logit; } else if (((pass & FR_LOGMASK) == FR_LOGP) || (FR_ISPASS(pass) && (fr_flags & FF_LOGPASS))) { if ((pass & FR_LOGMASK) != FR_LOGP) pass |= FF_LOGPASS; ATOMIC_INCL(frstats[out].fr_ppkl); goto logit; } else if (((pass & FR_LOGMASK) == FR_LOGB) || (FR_ISBLOCK(pass) && (fr_flags & FF_LOGBLOCK))) { if ((pass & FR_LOGMASK) != FR_LOGB) pass |= FF_LOGBLOCK; ATOMIC_INCL(frstats[out].fr_bpkl); logit: if (ipflog(fin, pass) == -1) { ATOMIC_INCL(frstats[out].fr_skip); /* * If the "or-block" option has been used then * block the packet if we failed to log it. */ if ((pass & FR_LOGORBLOCK) && FR_ISPASS(pass)) { pass &= ~FR_CMDMASK; pass |= FR_BLOCK; } } *passp = pass; } return fin->fin_fr; } #endif /* IPFILTER_LOG */ /* ------------------------------------------------------------------------ */ /* Function: ipf_cksum */ /* Returns: u_short - IP header checksum */ /* Parameters: addr(I) - pointer to start of buffer to checksum */ /* len(I) - length of buffer in bytes */ /* */ /* Calculate the two's complement 16 bit checksum of the buffer passed. */ /* */ /* N.B.: addr should be 16bit aligned. */ /* ------------------------------------------------------------------------ */ u_short ipf_cksum(addr, len) u_short *addr; int len; { u_32_t sum = 0; for (sum = 0; len > 1; len -= 2) sum += *addr++; /* mop up an odd byte, if necessary */ if (len == 1) sum += *(u_char *)addr; /* * add back carry outs from top 16 bits to low 16 bits */ sum = (sum >> 16) + (sum & 0xffff); /* add hi 16 to low 16 */ sum += (sum >> 16); /* add carry */ return (u_short)(~sum); } /* ------------------------------------------------------------------------ */ /* Function: fr_cksum */ /* Returns: u_short - layer 4 checksum */ /* Parameters: m(I ) - pointer to buffer holding packet */ /* ip(I) - pointer to IP header */ /* l4proto(I) - protocol to caclulate checksum for */ /* l4hdr(I) - pointer to layer 4 header */ /* l3len(I) - length of layer 4 data plus layer 3 header */ /* */ /* Calculates the TCP checksum for the packet held in "m", using the data */ /* in the IP header "ip" to seed it. */ /* */ /* NB: This function assumes we've pullup'd enough for all of the IP header */ /* and the TCP header. We also assume that data blocks aren't allocated in */ /* odd sizes. */ /* */ /* For IPv6, l3len excludes extension header size. */ /* */ /* Expects ip_len to be in host byte order when called. */ /* ------------------------------------------------------------------------ */ u_short fr_cksum(m, ip, l4proto, l4hdr, l3len) mb_t *m; ip_t *ip; int l4proto, l3len; void *l4hdr; { u_short *sp, slen, sumsave, l4hlen, *csump; u_int sum, sum2; int hlen; #ifdef USE_INET6 ip6_t *ip6; #endif csump = NULL; sumsave = 0; l4hlen = 0; sp = NULL; slen = 0; hlen = 0; sum = 0; /* * Add up IP Header portion */ #ifdef USE_INET6 if (IP_V(ip) == 4) { #endif hlen = IP_HL(ip) << 2; slen = l3len - hlen; sum = htons((u_short)l4proto); sum += htons(slen); sp = (u_short *)&ip->ip_src; sum += *sp++; /* ip_src */ sum += *sp++; sum += *sp++; /* ip_dst */ sum += *sp++; #ifdef USE_INET6 } else if (IP_V(ip) == 6) { ip6 = (ip6_t *)ip; hlen = sizeof(*ip6); slen = l3len - hlen; sum = htons((u_short)l4proto); sum += htons(slen); sp = (u_short *)&ip6->ip6_src; sum += *sp++; /* ip6_src */ sum += *sp++; sum += *sp++; sum += *sp++; sum += *sp++; sum += *sp++; sum += *sp++; sum += *sp++; sum += *sp++; /* ip6_dst */ sum += *sp++; sum += *sp++; sum += *sp++; sum += *sp++; sum += *sp++; sum += *sp++; sum += *sp++; } #endif switch (l4proto) { case IPPROTO_UDP : csump = &((udphdr_t *)l4hdr)->uh_sum; l4hlen = sizeof(udphdr_t); break; case IPPROTO_TCP : csump = &((tcphdr_t *)l4hdr)->th_sum; l4hlen = sizeof(tcphdr_t); break; case IPPROTO_ICMP : csump = &((icmphdr_t *)l4hdr)->icmp_cksum; l4hlen = 4; sum = 0; break; default : break; } if (csump != NULL) { sumsave = *csump; *csump = 0; } l4hlen = l4hlen; /* LINT */ #ifdef _KERNEL # ifdef MENTAT { void *rp = m->b_rptr; if ((unsigned char *)ip > m->b_rptr && (unsigned char *)ip < m->b_wptr) m->b_rptr = (u_char *)ip; sum2 = ip_cksum(m, hlen, sum); /* hlen == offset */ m->b_rptr = rp; sum2 = (u_short)(~sum2 & 0xffff); } # else /* MENTAT */ # if defined(BSD) || defined(sun) # if BSD >= 199103 m->m_data += hlen; # else m->m_off += hlen; # endif m->m_len -= hlen; sum2 = in_cksum(m, slen); m->m_len += hlen; # if BSD >= 199103 m->m_data -= hlen; # else m->m_off -= hlen; # endif /* * Both sum and sum2 are partial sums, so combine them together. */ sum += ~sum2 & 0xffff; while (sum > 0xffff) sum = (sum & 0xffff) + (sum >> 16); sum2 = ~sum & 0xffff; # else /* defined(BSD) || defined(sun) */ { union { u_char c[2]; u_short s; } bytes; u_short len = ip->ip_len; # if defined(__sgi) int add; # endif /* * Add up IP Header portion */ if (sp != (u_short *)l4hdr) sp = (u_short *)l4hdr; switch (l4proto) { case IPPROTO_UDP : sum += *sp++; /* sport */ sum += *sp++; /* dport */ sum += *sp++; /* udp length */ sum += *sp++; /* checksum */ break; case IPPROTO_TCP : sum += *sp++; /* sport */ sum += *sp++; /* dport */ sum += *sp++; /* seq */ sum += *sp++; sum += *sp++; /* ack */ sum += *sp++; sum += *sp++; /* off */ sum += *sp++; /* win */ sum += *sp++; /* checksum */ sum += *sp++; /* urp */ break; case IPPROTO_ICMP : sum = *sp++; /* type/code */ sum += *sp++; /* checksum */ break; } # ifdef __sgi /* * In case we had to copy the IP & TCP header out of mbufs, * skip over the mbuf bits which are the header */ if ((char *)ip != mtod(m, char *)) { hlen = (char *)sp - (char *)ip; while (hlen) { add = MIN(hlen, m->m_len); sp = (u_short *)(mtod(m, caddr_t) + add); hlen -= add; if (add == m->m_len) { m = m->m_next; if (!hlen) { if (!m) break; sp = mtod(m, u_short *); } PANIC((!m),("fr_cksum(1): not enough data")); } } } # endif len -= (l4hlen + hlen); if (len <= 0) goto nodata; while (len > 1) { if (((char *)sp - mtod(m, char *)) >= m->m_len) { m = m->m_next; PANIC((!m),("fr_cksum(2): not enough data")); sp = mtod(m, u_short *); } if (((char *)(sp + 1) - mtod(m, char *)) > m->m_len) { bytes.c[0] = *(u_char *)sp; m = m->m_next; PANIC((!m),("fr_cksum(3): not enough data")); sp = mtod(m, u_short *); bytes.c[1] = *(u_char *)sp; sum += bytes.s; sp = (u_short *)((u_char *)sp + 1); } if ((u_long)sp & 1) { bcopy((char *)sp++, (char *)&bytes.s, sizeof(bytes.s)); sum += bytes.s; } else sum += *sp++; len -= 2; } if (len != 0) sum += ntohs(*(u_char *)sp << 8); nodata: while (sum > 0xffff) sum = (sum & 0xffff) + (sum >> 16); sum2 = (u_short)(~sum & 0xffff); } # endif /* defined(BSD) || defined(sun) */ # endif /* MENTAT */ #else /* _KERNEL */ /* * Add up IP Header portion */ if (sp != (u_short *)l4hdr) sp = (u_short *)l4hdr; for (; slen > 1; slen -= 2) sum += *sp++; if (slen) sum += ntohs(*(u_char *)sp << 8); while (sum > 0xffff) sum = (sum & 0xffff) + (sum >> 16); sum2 = (u_short)(~sum & 0xffff); #endif /* _KERNEL */ if (csump != NULL) *csump = sumsave; return sum2; } #if defined(_KERNEL) && ( ((BSD < 199103) && !defined(MENTAT)) || \ defined(__sgi) ) && !defined(linux) && !defined(_AIX51) /* * Copyright (c) 1982, 1986, 1988, 1991, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)uipc_mbuf.c 8.2 (Berkeley) 1/4/94 * $Id: fil.c,v 2.243.2.125 2007/10/10 09:27:20 darrenr Exp $ */ /* * Copy data from an mbuf chain starting "off" bytes from the beginning, * continuing for "len" bytes, into the indicated buffer. */ void m_copydata(m, off, len, cp) mb_t *m; int off; int len; caddr_t cp; { unsigned count; if (off < 0 || len < 0) panic("m_copydata"); while (off > 0) { if (m == 0) panic("m_copydata"); if (off < m->m_len) break; off -= m->m_len; m = m->m_next; } while (len > 0) { if (m == 0) panic("m_copydata"); count = MIN(m->m_len - off, len); bcopy(mtod(m, caddr_t) + off, cp, count); len -= count; cp += count; off = 0; m = m->m_next; } } /* * Copy data from a buffer back into the indicated mbuf chain, * starting "off" bytes from the beginning, extending the mbuf * chain if necessary. */ void m_copyback(m0, off, len, cp) struct mbuf *m0; int off; int len; caddr_t cp; { int mlen; struct mbuf *m = m0, *n; int totlen = 0; if (m0 == 0) return; while (off > (mlen = m->m_len)) { off -= mlen; totlen += mlen; if (m->m_next == 0) { n = m_getclr(M_DONTWAIT, m->m_type); if (n == 0) goto out; n->m_len = min(MLEN, len + off); m->m_next = n; } m = m->m_next; } while (len > 0) { mlen = min(m->m_len - off, len); bcopy(cp, off + mtod(m, caddr_t), (unsigned)mlen); cp += mlen; len -= mlen; mlen += off; off = 0; totlen += mlen; if (len == 0) break; if (m->m_next == 0) { n = m_get(M_DONTWAIT, m->m_type); if (n == 0) break; n->m_len = min(MLEN, len); m->m_next = n; } m = m->m_next; } out: #if 0 if (((m = m0)->m_flags & M_PKTHDR) && (m->m_pkthdr.len < totlen)) m->m_pkthdr.len = totlen; #endif return; } #endif /* (_KERNEL) && ( ((BSD < 199103) && !MENTAT) || __sgi) */ /* ------------------------------------------------------------------------ */ /* Function: fr_findgroup */ /* Returns: frgroup_t * - NULL = group not found, else pointer to group */ /* Parameters: group(I) - group name to search for */ /* unit(I) - device to which this group belongs */ /* set(I) - which set of rules (inactive/inactive) this is */ /* fgpp(O) - pointer to place to store pointer to the pointer */ /* to where to add the next (last) group or where */ /* to delete group from. */ /* */ /* Search amongst the defined groups for a particular group number. */ /* ------------------------------------------------------------------------ */ frgroup_t *fr_findgroup(group, unit, set, fgpp) char *group; minor_t unit; int set; frgroup_t ***fgpp; { frgroup_t *fg, **fgp; /* * Which list of groups to search in is dependent on which list of * rules are being operated on. */ fgp = &ipfgroups[unit][set]; while ((fg = *fgp) != NULL) { if (strncmp(group, fg->fg_name, FR_GROUPLEN) == 0) break; else fgp = &fg->fg_next; } if (fgpp != NULL) *fgpp = fgp; return fg; } /* ------------------------------------------------------------------------ */ /* Function: fr_addgroup */ /* Returns: frgroup_t * - NULL == did not create group, */ /* != NULL == pointer to the group */ /* Parameters: num(I) - group number to add */ /* head(I) - rule pointer that is using this as the head */ /* flags(I) - rule flags which describe the type of rule it is */ /* unit(I) - device to which this group will belong to */ /* set(I) - which set of rules (inactive/inactive) this is */ /* Write Locks: ipf_mutex */ /* */ /* Add a new group head, or if it already exists, increase the reference */ /* count to it. */ /* ------------------------------------------------------------------------ */ frgroup_t *fr_addgroup(group, head, flags, unit, set) char *group; void *head; u_32_t flags; minor_t unit; int set; { frgroup_t *fg, **fgp; u_32_t gflags; if (group == NULL) return NULL; if (unit == IPL_LOGIPF && *group == '\0') return NULL; fgp = NULL; gflags = flags & FR_INOUT; fg = fr_findgroup(group, unit, set, &fgp); if (fg != NULL) { if (fg->fg_flags == 0) fg->fg_flags = gflags; else if (gflags != fg->fg_flags) return NULL; fg->fg_ref++; return fg; } KMALLOC(fg, frgroup_t *); if (fg != NULL) { fg->fg_head = head; fg->fg_start = NULL; fg->fg_next = *fgp; bcopy(group, fg->fg_name, FR_GROUPLEN); fg->fg_flags = gflags; fg->fg_ref = 1; *fgp = fg; } return fg; } /* ------------------------------------------------------------------------ */ /* Function: fr_delgroup */ /* Returns: Nil */ /* Parameters: group(I) - group name to delete */ /* unit(I) - device to which this group belongs */ /* set(I) - which set of rules (inactive/inactive) this is */ /* Write Locks: ipf_mutex */ /* */ /* Attempt to delete a group head. */ /* Only do this when its reference count reaches 0. */ /* ------------------------------------------------------------------------ */ void fr_delgroup(group, unit, set) char *group; minor_t unit; int set; { frgroup_t *fg, **fgp; fg = fr_findgroup(group, unit, set, &fgp); if (fg == NULL) return; fg->fg_ref--; if (fg->fg_ref == 0) { *fgp = fg->fg_next; KFREE(fg); } } /* ------------------------------------------------------------------------ */ /* Function: fr_getrulen */ /* Returns: frentry_t * - NULL == not found, else pointer to rule n */ /* Parameters: unit(I) - device for which to count the rule's number */ /* flags(I) - which set of rules to find the rule in */ /* group(I) - group name */ /* n(I) - rule number to find */ /* */ /* Find rule # n in group # g and return a pointer to it. Return NULl if */ /* group # g doesn't exist or there are less than n rules in the group. */ /* ------------------------------------------------------------------------ */ frentry_t *fr_getrulen(unit, group, n) int unit; char *group; u_32_t n; { frentry_t *fr; frgroup_t *fg; fg = fr_findgroup(group, unit, fr_active, NULL); if (fg == NULL) return NULL; for (fr = fg->fg_head; fr && n; fr = fr->fr_next, n--) ; if (n != 0) return NULL; return fr; } /* ------------------------------------------------------------------------ */ /* Function: fr_rulen */ /* Returns: int - >= 0 - rule number, -1 == search failed */ /* Parameters: unit(I) - device for which to count the rule's number */ /* fr(I) - pointer to rule to match */ /* */ /* Return the number for a rule on a specific filtering device. */ /* ------------------------------------------------------------------------ */ int fr_rulen(unit, fr) int unit; frentry_t *fr; { frentry_t *fh; frgroup_t *fg; u_32_t n = 0; if (fr == NULL) return -1; fg = fr_findgroup(fr->fr_group, unit, fr_active, NULL); if (fg == NULL) return -1; for (fh = fg->fg_head; fh; n++, fh = fh->fr_next) if (fh == fr) break; if (fh == NULL) return -1; return n; } /* ------------------------------------------------------------------------ */ /* Function: frflushlist */ /* Returns: int - >= 0 - number of flushed rules */ /* Parameters: set(I) - which set of rules (inactive/inactive) this is */ /* unit(I) - device for which to flush rules */ /* flags(I) - which set of rules to flush */ /* nfreedp(O) - pointer to int where flush count is stored */ /* listp(I) - pointer to list to flush pointer */ /* Write Locks: ipf_mutex */ /* */ /* Recursively flush rules from the list, descending groups as they are */ /* encountered. if a rule is the head of a group and it has lost all its */ /* group members, then also delete the group reference. nfreedp is needed */ /* to store the accumulating count of rules removed, whereas the returned */ /* value is just the number removed from the current list. The latter is */ /* needed to correctly adjust reference counts on rules that define groups. */ /* */ /* NOTE: Rules not loaded from user space cannot be flushed. */ /* ------------------------------------------------------------------------ */ static int frflushlist(set, unit, nfreedp, listp) int set; minor_t unit; int *nfreedp; frentry_t **listp; { int freed = 0; frentry_t *fp; while ((fp = *listp) != NULL) { if ((fp->fr_type & FR_T_BUILTIN) || !(fp->fr_flags & FR_COPIED)) { listp = &fp->fr_next; continue; } *listp = fp->fr_next; if (fp->fr_grp != NULL) { (void) frflushlist(set, unit, nfreedp, fp->fr_grp); } if (fp->fr_grhead != NULL) { fr_delgroup(fp->fr_grhead, unit, set); *fp->fr_grhead = '\0'; } ASSERT(fp->fr_ref > 0); fp->fr_next = NULL; if (fr_derefrule(&fp) == 0) freed++; } *nfreedp += freed; return freed; } /* ------------------------------------------------------------------------ */ /* Function: frflush */ /* Returns: int - >= 0 - number of flushed rules */ /* Parameters: unit(I) - device for which to flush rules */ /* flags(I) - which set of rules to flush */ /* */ /* Calls flushlist() for all filter rules (accounting, firewall - both IPv4 */ /* and IPv6) as defined by the value of flags. */ /* ------------------------------------------------------------------------ */ int frflush(unit, proto, flags) minor_t unit; int proto, flags; { int flushed = 0, set; WRITE_ENTER(&ipf_mutex); bzero((char *)frcache, sizeof(frcache)); set = fr_active; if ((flags & FR_INACTIVE) == FR_INACTIVE) set = 1 - set; if (flags & FR_OUTQUE) { if (proto == 0 || proto == 6) { (void) frflushlist(set, unit, &flushed, &ipfilter6[1][set]); (void) frflushlist(set, unit, &flushed, &ipacct6[1][set]); } if (proto == 0 || proto == 4) { (void) frflushlist(set, unit, &flushed, &ipfilter[1][set]); (void) frflushlist(set, unit, &flushed, &ipacct[1][set]); } } if (flags & FR_INQUE) { if (proto == 0 || proto == 6) { (void) frflushlist(set, unit, &flushed, &ipfilter6[0][set]); (void) frflushlist(set, unit, &flushed, &ipacct6[0][set]); } if (proto == 0 || proto == 4) { (void) frflushlist(set, unit, &flushed, &ipfilter[0][set]); (void) frflushlist(set, unit, &flushed, &ipacct[0][set]); } } RWLOCK_EXIT(&ipf_mutex); if (unit == IPL_LOGIPF) { int tmp; tmp = frflush(IPL_LOGCOUNT, proto, flags); if (tmp >= 0) flushed += tmp; } return flushed; } /* ------------------------------------------------------------------------ */ /* Function: memstr */ /* Returns: char * - NULL if failed, != NULL pointer to matching bytes */ /* Parameters: src(I) - pointer to byte sequence to match */ /* dst(I) - pointer to byte sequence to search */ /* slen(I) - match length */ /* dlen(I) - length available to search in */ /* */ /* Search dst for a sequence of bytes matching those at src and extend for */ /* slen bytes. */ /* ------------------------------------------------------------------------ */ char *memstr(src, dst, slen, dlen) const char *src; char *dst; size_t slen, dlen; { char *s = NULL; while (dlen >= slen) { if (bcmp(src, dst, slen) == 0) { s = dst; break; } dst++; dlen--; } return s; } /* ------------------------------------------------------------------------ */ /* Function: fr_fixskip */ /* Returns: Nil */ /* Parameters: listp(IO) - pointer to start of list with skip rule */ /* rp(I) - rule added/removed with skip in it. */ /* addremove(I) - adjustment (-1/+1) to make to skip count, */ /* depending on whether a rule was just added */ /* or removed. */ /* */ /* Adjust all the rules in a list which would have skip'd past the position */ /* where we are inserting to skip to the right place given the change. */ /* ------------------------------------------------------------------------ */ void fr_fixskip(listp, rp, addremove) frentry_t **listp, *rp; int addremove; { int rules, rn; frentry_t *fp; rules = 0; for (fp = *listp; (fp != NULL) && (fp != rp); fp = fp->fr_next) rules++; if (!fp) return; for (rn = 0, fp = *listp; fp && (fp != rp); fp = fp->fr_next, rn++) if (FR_ISSKIP(fp->fr_flags) && (rn + fp->fr_arg >= rules)) fp->fr_arg += addremove; } #ifdef _KERNEL /* ------------------------------------------------------------------------ */ /* Function: count4bits */ /* Returns: int - >= 0 - number of consecutive bits in input */ /* Parameters: ip(I) - 32bit IP address */ /* */ /* IPv4 ONLY */ /* count consecutive 1's in bit mask. If the mask generated by counting */ /* consecutive 1's is different to that passed, return -1, else return # */ /* of bits. */ /* ------------------------------------------------------------------------ */ int count4bits(ip) u_32_t ip; { u_32_t ipn; int cnt = 0, i, j; ip = ipn = ntohl(ip); for (i = 32; i; i--, ipn *= 2) if (ipn & 0x80000000) cnt++; else break; ipn = 0; for (i = 32, j = cnt; i; i--, j--) { ipn *= 2; if (j > 0) ipn++; } if (ipn == ip) return cnt; return -1; } # if 0 /* ------------------------------------------------------------------------ */ /* Function: count6bits */ /* Returns: int - >= 0 - number of consecutive bits in input */ /* Parameters: msk(I) - pointer to start of IPv6 bitmask */ /* */ /* IPv6 ONLY */ /* count consecutive 1's in bit mask. */ /* ------------------------------------------------------------------------ */ int count6bits(msk) u_32_t *msk; { int i = 0, k; u_32_t j; for (k = 3; k >= 0; k--) if (msk[k] == 0xffffffff) i += 32; else { for (j = msk[k]; j; j <<= 1) if (j & 0x80000000) i++; } return i; } # endif #endif /* _KERNEL */ /* ------------------------------------------------------------------------ */ /* Function: frsynclist */ /* Returns: void */ /* Parameters: fr(I) - start of filter list to sync interface names for */ /* ifp(I) - interface pointer for limiting sync lookups */ /* Write Locks: ipf_mutex */ /* */ /* Walk through a list of filter rules and resolve any interface names into */ /* pointers. Where dynamic addresses are used, also update the IP address */ /* used in the rule. The interface pointer is used to limit the lookups to */ /* a specific set of matching names if it is non-NULL. */ /* ------------------------------------------------------------------------ */ static void frsynclist(fr, ifp) frentry_t *fr; void *ifp; { frdest_t *fdp; int v, i; for (; fr; fr = fr->fr_next) { v = fr->fr_v; /* * Lookup all the interface names that are part of the rule. */ for (i = 0; i < 4; i++) { if ((ifp != NULL) && (fr->fr_ifas[i] != ifp)) continue; fr->fr_ifas[i] = fr_resolvenic(fr->fr_ifnames[i], v); } if (fr->fr_type == FR_T_IPF) { if (fr->fr_satype != FRI_NORMAL && fr->fr_satype != FRI_LOOKUP) { (void)fr_ifpaddr(v, fr->fr_satype, fr->fr_ifas[fr->fr_sifpidx], &fr->fr_src, &fr->fr_smsk); } if (fr->fr_datype != FRI_NORMAL && fr->fr_datype != FRI_LOOKUP) { (void)fr_ifpaddr(v, fr->fr_datype, fr->fr_ifas[fr->fr_difpidx], &fr->fr_dst, &fr->fr_dmsk); } } fdp = &fr->fr_tifs[0]; if ((ifp == NULL) || (fdp->fd_ifp == ifp)) fr_resolvedest(fdp, v); fdp = &fr->fr_tifs[1]; if ((ifp == NULL) || (fdp->fd_ifp == ifp)) fr_resolvedest(fdp, v); fdp = &fr->fr_dif; if ((ifp == NULL) || (fdp->fd_ifp == ifp)) { fr_resolvedest(fdp, v); fr->fr_flags &= ~FR_DUP; if ((fdp->fd_ifp != (void *)-1) && (fdp->fd_ifp != NULL)) fr->fr_flags |= FR_DUP; } #ifdef IPFILTER_LOOKUP if (fr->fr_type == FR_T_IPF && fr->fr_satype == FRI_LOOKUP && fr->fr_srcptr == NULL) { fr->fr_srcptr = fr_resolvelookup(fr->fr_srctype, fr->fr_srcsubtype, &fr->fr_slookup, &fr->fr_srcfunc); } if (fr->fr_type == FR_T_IPF && fr->fr_datype == FRI_LOOKUP && fr->fr_dstptr == NULL) { fr->fr_dstptr = fr_resolvelookup(fr->fr_dsttype, fr->fr_dstsubtype, &fr->fr_dlookup, &fr->fr_dstfunc); } #endif } } #ifdef _KERNEL /* ------------------------------------------------------------------------ */ /* Function: frsync */ /* Returns: void */ /* Parameters: Nil */ /* */ /* frsync() is called when we suspect that the interface list or */ /* information about interfaces (like IP#) has changed. Go through all */ /* filter rules, NAT entries and the state table and check if anything */ /* needs to be changed/updated. */ /* ------------------------------------------------------------------------ */ void frsync(ifp) void *ifp; { int i; # if !SOLARIS fr_natsync(ifp); fr_statesync(ifp); # endif WRITE_ENTER(&ipf_mutex); frsynclist(ipacct[0][fr_active], ifp); frsynclist(ipacct[1][fr_active], ifp); frsynclist(ipfilter[0][fr_active], ifp); frsynclist(ipfilter[1][fr_active], ifp); frsynclist(ipacct6[0][fr_active], ifp); frsynclist(ipacct6[1][fr_active], ifp); frsynclist(ipfilter6[0][fr_active], ifp); frsynclist(ipfilter6[1][fr_active], ifp); for (i = 0; i < IPL_LOGSIZE; i++) { frgroup_t *g; for (g = ipfgroups[i][0]; g != NULL; g = g->fg_next) frsynclist(g->fg_start, ifp); for (g = ipfgroups[i][1]; g != NULL; g = g->fg_next) frsynclist(g->fg_start, ifp); } RWLOCK_EXIT(&ipf_mutex); } /* * In the functions below, bcopy() is called because the pointer being * copied _from_ in this instance is a pointer to a char buf (which could * end up being unaligned) and on the kernel's local stack. */ /* ------------------------------------------------------------------------ */ /* Function: copyinptr */ /* Returns: int - 0 = success, else failure */ /* Parameters: src(I) - pointer to the source address */ /* dst(I) - destination address */ /* size(I) - number of bytes to copy */ /* */ /* Copy a block of data in from user space, given a pointer to the pointer */ /* to start copying from (src) and a pointer to where to store it (dst). */ /* NB: src - pointer to user space pointer, dst - kernel space pointer */ /* ------------------------------------------------------------------------ */ int copyinptr(src, dst, size) void *src, *dst; size_t size; { caddr_t ca; int error; # if SOLARIS error = COPYIN(src, &ca, sizeof(ca)); if (error != 0) return error; # else bcopy(src, (caddr_t)&ca, sizeof(ca)); # endif error = COPYIN(ca, dst, size); if (error != 0) error = EFAULT; return error; } /* ------------------------------------------------------------------------ */ /* Function: copyoutptr */ /* Returns: int - 0 = success, else failure */ /* Parameters: src(I) - pointer to the source address */ /* dst(I) - destination address */ /* size(I) - number of bytes to copy */ /* */ /* Copy a block of data out to user space, given a pointer to the pointer */ /* to start copying from (src) and a pointer to where to store it (dst). */ /* NB: src - kernel space pointer, dst - pointer to user space pointer. */ /* ------------------------------------------------------------------------ */ int copyoutptr(src, dst, size) void *src, *dst; size_t size; { caddr_t ca; int error; bcopy(dst, (caddr_t)&ca, sizeof(ca)); error = COPYOUT(src, ca, size); if (error != 0) error = EFAULT; return error; } #endif /* ------------------------------------------------------------------------ */ /* Function: fr_lock */ /* Returns: int - 0 = success, else error */ /* Parameters: data(I) - pointer to lock value to set */ /* lockp(O) - pointer to location to store old lock value */ /* */ /* Get the new value for the lock integer, set it and return the old value */ /* in *lockp. */ /* ------------------------------------------------------------------------ */ int fr_lock(data, lockp) caddr_t data; int *lockp; { int arg, err; err = BCOPYIN(data, &arg, sizeof(arg)); if (err != 0) return EFAULT; err = BCOPYOUT(lockp, data, sizeof(*lockp)); if (err != 0) return EFAULT; *lockp = arg; return 0; } /* ------------------------------------------------------------------------ */ /* Function: fr_getstat */ /* Returns: Nil */ /* Parameters: fiop(I) - pointer to ipfilter stats structure */ /* */ /* Stores a copy of current pointers, counters, etc, in the friostat */ /* structure. */ /* ------------------------------------------------------------------------ */ void fr_getstat(fiop) friostat_t *fiop; { int i, j; bcopy((char *)frstats, (char *)fiop->f_st, sizeof(filterstats_t) * 2); fiop->f_locks[IPL_LOGSTATE] = fr_state_lock; fiop->f_locks[IPL_LOGNAT] = fr_nat_lock; fiop->f_locks[IPL_LOGIPF] = fr_frag_lock; fiop->f_locks[IPL_LOGAUTH] = fr_auth_lock; for (i = 0; i < 2; i++) for (j = 0; j < 2; j++) { fiop->f_ipf[i][j] = ipfilter[i][j]; fiop->f_acct[i][j] = ipacct[i][j]; fiop->f_ipf6[i][j] = ipfilter6[i][j]; fiop->f_acct6[i][j] = ipacct6[i][j]; } fiop->f_ticks = fr_ticks; fiop->f_active = fr_active; fiop->f_froute[0] = fr_frouteok[0]; fiop->f_froute[1] = fr_frouteok[1]; fiop->f_running = fr_running; for (i = 0; i < IPL_LOGSIZE; i++) { fiop->f_groups[i][0] = ipfgroups[i][0]; fiop->f_groups[i][1] = ipfgroups[i][1]; } #ifdef IPFILTER_LOG fiop->f_logging = 1; #else fiop->f_logging = 0; #endif fiop->f_defpass = fr_pass; fiop->f_features = fr_features; (void) strncpy(fiop->f_version, ipfilter_version, sizeof(fiop->f_version)); } #ifdef USE_INET6 int icmptoicmp6types[ICMP_MAXTYPE+1] = { ICMP6_ECHO_REPLY, /* 0: ICMP_ECHOREPLY */ -1, /* 1: UNUSED */ -1, /* 2: UNUSED */ ICMP6_DST_UNREACH, /* 3: ICMP_UNREACH */ -1, /* 4: ICMP_SOURCEQUENCH */ ND_REDIRECT, /* 5: ICMP_REDIRECT */ -1, /* 6: UNUSED */ -1, /* 7: UNUSED */ ICMP6_ECHO_REQUEST, /* 8: ICMP_ECHO */ -1, /* 9: UNUSED */ -1, /* 10: UNUSED */ ICMP6_TIME_EXCEEDED, /* 11: ICMP_TIMXCEED */ ICMP6_PARAM_PROB, /* 12: ICMP_PARAMPROB */ -1, /* 13: ICMP_TSTAMP */ -1, /* 14: ICMP_TSTAMPREPLY */ -1, /* 15: ICMP_IREQ */ -1, /* 16: ICMP_IREQREPLY */ -1, /* 17: ICMP_MASKREQ */ -1, /* 18: ICMP_MASKREPLY */ }; int icmptoicmp6unreach[ICMP_MAX_UNREACH] = { ICMP6_DST_UNREACH_ADDR, /* 0: ICMP_UNREACH_NET */ ICMP6_DST_UNREACH_ADDR, /* 1: ICMP_UNREACH_HOST */ -1, /* 2: ICMP_UNREACH_PROTOCOL */ ICMP6_DST_UNREACH_NOPORT, /* 3: ICMP_UNREACH_PORT */ -1, /* 4: ICMP_UNREACH_NEEDFRAG */ ICMP6_DST_UNREACH_NOTNEIGHBOR, /* 5: ICMP_UNREACH_SRCFAIL */ ICMP6_DST_UNREACH_ADDR, /* 6: ICMP_UNREACH_NET_UNKNOWN */ ICMP6_DST_UNREACH_ADDR, /* 7: ICMP_UNREACH_HOST_UNKNOWN */ -1, /* 8: ICMP_UNREACH_ISOLATED */ ICMP6_DST_UNREACH_ADMIN, /* 9: ICMP_UNREACH_NET_PROHIB */ ICMP6_DST_UNREACH_ADMIN, /* 10: ICMP_UNREACH_HOST_PROHIB */ -1, /* 11: ICMP_UNREACH_TOSNET */ -1, /* 12: ICMP_UNREACH_TOSHOST */ ICMP6_DST_UNREACH_ADMIN, /* 13: ICMP_UNREACH_ADMIN_PROHIBIT */ }; int icmpreplytype6[ICMP6_MAXTYPE + 1]; #endif int icmpreplytype4[ICMP_MAXTYPE + 1]; /* ------------------------------------------------------------------------ */ /* Function: fr_matchicmpqueryreply */ /* Returns: int - 1 if "icmp" is a valid reply to "ic" else 0. */ /* Parameters: v(I) - IP protocol version (4 or 6) */ /* ic(I) - ICMP information */ /* icmp(I) - ICMP packet header */ /* rev(I) - direction (0 = forward/1 = reverse) of packet */ /* */ /* Check if the ICMP packet defined by the header pointed to by icmp is a */ /* reply to one as described by what's in ic. If it is a match, return 1, */ /* else return 0 for no match. */ /* ------------------------------------------------------------------------ */ int fr_matchicmpqueryreply(v, ic, icmp, rev) int v; icmpinfo_t *ic; icmphdr_t *icmp; int rev; { int ictype; ictype = ic->ici_type; if (v == 4) { /* * If we matched its type on the way in, then when going out * it will still be the same type. */ if ((!rev && (icmp->icmp_type == ictype)) || (rev && (icmpreplytype4[ictype] == icmp->icmp_type))) { if (icmp->icmp_type != ICMP_ECHOREPLY) return 1; if (icmp->icmp_id == ic->ici_id) return 1; } } #ifdef USE_INET6 else if (v == 6) { if ((!rev && (icmp->icmp_type == ictype)) || (rev && (icmpreplytype6[ictype] == icmp->icmp_type))) { if (icmp->icmp_type != ICMP6_ECHO_REPLY) return 1; if (icmp->icmp_id == ic->ici_id) return 1; } } #endif return 0; } #ifdef IPFILTER_LOOKUP /* ------------------------------------------------------------------------ */ /* Function: fr_resolvelookup */ /* Returns: void * - NULL = failure, else success. */ /* Parameters: type(I) - type of lookup these parameters are for. */ /* subtype(I) - whether the info below contains number/name */ /* info(I) - pointer to name/number of the lookup data */ /* funcptr(IO) - pointer to pointer for storing IP address */ /* searching function. */ /* */ /* Search for the "table" number passed in amongst those configured for */ /* that particular type. If the type is recognised then the function to */ /* call to do the IP address search will be change, regardless of whether */ /* or not the "table" number exists. */ /* ------------------------------------------------------------------------ */ static void *fr_resolvelookup(type, subtype, info, funcptr) u_int type, subtype; i6addr_t *info; lookupfunc_t *funcptr; { char label[FR_GROUPLEN], *name; iphtable_t *iph; ip_pool_t *ipo; void *ptr; if (subtype == 0) { #if defined(SNPRINTF) && defined(_KERNEL) SNPRINTF(label, sizeof(label), "%u", info->iplookupnum); #else (void) sprintf(label, "%u", info->iplookupnum); #endif name = label; } else if (subtype == 1) { /* * Because iplookupname is currently only a 12 character * string and FR_GROUPLEN is 16, copy all of it into the * label buffer and add on a NULL at the end. */ strncpy(label, info->iplookupname, sizeof(info->iplookupname)); label[sizeof(info->iplookupname)] = '\0'; name = label; } else { return NULL; } READ_ENTER(&ip_poolrw); switch (type) { case IPLT_POOL : # if (defined(__osf__) && defined(_KERNEL)) ptr = NULL; *funcptr = NULL; # else ipo = ip_pool_find(IPL_LOGIPF, name); ptr = ipo; if (ipo != NULL) { ATOMIC_INC32(ipo->ipo_ref); } *funcptr = ip_pool_search; # endif break; case IPLT_HASH : iph = fr_findhtable(IPL_LOGIPF, name); ptr = iph; if (iph != NULL) { ATOMIC_INC32(iph->iph_ref); } *funcptr = fr_iphmfindip; break; default: ptr = NULL; *funcptr = NULL; break; } RWLOCK_EXIT(&ip_poolrw); return ptr; } #endif /* ------------------------------------------------------------------------ */ /* Function: frrequest */ /* Returns: int - 0 == success, > 0 == errno value */ /* Parameters: unit(I) - device for which this is for */ /* req(I) - ioctl command (SIOC*) */ /* data(I) - pointr to ioctl data */ /* set(I) - 1 or 0 (filter set) */ /* makecopy(I) - flag indicating whether data points to a rule */ /* in kernel space & hence doesn't need copying. */ /* */ /* This function handles all the requests which operate on the list of */ /* filter rules. This includes adding, deleting, insertion. It is also */ /* responsible for creating groups when a "head" rule is loaded. Interface */ /* names are resolved here and other sanity checks are made on the content */ /* of the rule structure being loaded. If a rule has user defined timeouts */ /* then make sure they are created and initialised before exiting. */ /* ------------------------------------------------------------------------ */ int frrequest(unit, req, data, set, makecopy) int unit; ioctlcmd_t req; int set, makecopy; caddr_t data; { frentry_t frd, *fp, *f, **fprev, **ftail; int error = 0, in, v; void *ptr, *uptr; u_int *p, *pp; frgroup_t *fg; char *group; fg = NULL; fp = &frd; if (makecopy != 0) { error = fr_inobj(data, fp, IPFOBJ_FRENTRY); if (error) return EFAULT; if ((fp->fr_flags & FR_T_BUILTIN) != 0) return EINVAL; fp->fr_ref = 0; fp->fr_flags |= FR_COPIED; } else { fp = (frentry_t *)data; if ((fp->fr_type & FR_T_BUILTIN) == 0) return EINVAL; fp->fr_flags &= ~FR_COPIED; } if (((fp->fr_dsize == 0) && (fp->fr_data != NULL)) || ((fp->fr_dsize != 0) && (fp->fr_data == NULL))) return EINVAL; v = fp->fr_v; uptr = fp->fr_data; /* * Only filter rules for IPv4 or IPv6 are accepted. */ if (v == 4) /*EMPTY*/; #ifdef USE_INET6 else if (v == 6) /*EMPTY*/; #endif else { return EINVAL; } /* * If the rule is being loaded from user space, i.e. we had to copy it * into kernel space, then do not trust the function pointer in the * rule. */ if ((makecopy == 1) && (fp->fr_func != NULL)) { if (fr_findfunc(fp->fr_func) == NULL) return ESRCH; error = fr_funcinit(fp); if (error != 0) return error; } ptr = NULL; /* * Check that the group number does exist and that its use (in/out) * matches what the rule is. */ if (!strncmp(fp->fr_grhead, "0", FR_GROUPLEN)) *fp->fr_grhead = '\0'; group = fp->fr_group; if (!strncmp(group, "0", FR_GROUPLEN)) *group = '\0'; if (FR_ISACCOUNT(fp->fr_flags)) unit = IPL_LOGCOUNT; if ((req != (int)SIOCZRLST) && (*group != '\0')) { fg = fr_findgroup(group, unit, set, NULL); if (fg == NULL) return ESRCH; if (fg->fg_flags == 0) fg->fg_flags = fp->fr_flags & FR_INOUT; else if (fg->fg_flags != (fp->fr_flags & FR_INOUT)) return ESRCH; } in = (fp->fr_flags & FR_INQUE) ? 0 : 1; /* * Work out which rule list this change is being applied to. */ ftail = NULL; fprev = NULL; if (unit == IPL_LOGAUTH) fprev = &ipauth; else if (v == 4) { if (FR_ISACCOUNT(fp->fr_flags)) fprev = &ipacct[in][set]; else if ((fp->fr_flags & (FR_OUTQUE|FR_INQUE)) != 0) fprev = &ipfilter[in][set]; } else if (v == 6) { if (FR_ISACCOUNT(fp->fr_flags)) fprev = &ipacct6[in][set]; else if ((fp->fr_flags & (FR_OUTQUE|FR_INQUE)) != 0) fprev = &ipfilter6[in][set]; } if (fprev == NULL) return ESRCH; if (*group != '\0') { if (!fg && !(fg = fr_findgroup(group, unit, set, NULL))) return ESRCH; fprev = &fg->fg_start; } /* * Copy in extra data for the rule. */ if (fp->fr_dsize != 0) { if (makecopy != 0) { KMALLOCS(ptr, void *, fp->fr_dsize); if (!ptr) return ENOMEM; error = COPYIN(uptr, ptr, fp->fr_dsize); if (error != 0) error = EFAULT; } else { ptr = uptr; error = 0; } if (error != 0) { KFREES(ptr, fp->fr_dsize); return ENOMEM; } fp->fr_data = ptr; } else fp->fr_data = NULL; /* * Perform per-rule type sanity checks of their members. */ switch (fp->fr_type & ~FR_T_BUILTIN) { #if defined(IPFILTER_BPF) case FR_T_BPFOPC : if (fp->fr_dsize == 0) return EINVAL; if (!bpf_validate(ptr, fp->fr_dsize/sizeof(struct bpf_insn))) { if (makecopy && fp->fr_data != NULL) { KFREES(fp->fr_data, fp->fr_dsize); } return EINVAL; } break; #endif case FR_T_IPF : if (fp->fr_dsize != sizeof(fripf_t)) return EINVAL; /* * Allowing a rule with both "keep state" and "with oow" is * pointless because adding a state entry to the table will * fail with the out of window (oow) flag set. */ if ((fp->fr_flags & FR_KEEPSTATE) && (fp->fr_flx & FI_OOW)) return EINVAL; switch (fp->fr_satype) { case FRI_BROADCAST : case FRI_DYNAMIC : case FRI_NETWORK : case FRI_NETMASKED : case FRI_PEERADDR : if (fp->fr_sifpidx < 0 || fp->fr_sifpidx > 3) { if (makecopy && fp->fr_data != NULL) { KFREES(fp->fr_data, fp->fr_dsize); } return EINVAL; } break; #ifdef IPFILTER_LOOKUP case FRI_LOOKUP : fp->fr_srcptr = fr_resolvelookup(fp->fr_srctype, fp->fr_srcsubtype, &fp->fr_slookup, &fp->fr_srcfunc); if (fp->fr_srcptr == NULL) return ESRCH; break; #endif default : break; } switch (fp->fr_datype) { case FRI_BROADCAST : case FRI_DYNAMIC : case FRI_NETWORK : case FRI_NETMASKED : case FRI_PEERADDR : if (fp->fr_difpidx < 0 || fp->fr_difpidx > 3) { if (makecopy && fp->fr_data != NULL) { KFREES(fp->fr_data, fp->fr_dsize); } return EINVAL; } break; #ifdef IPFILTER_LOOKUP case FRI_LOOKUP : fp->fr_dstptr = fr_resolvelookup(fp->fr_dsttype, fp->fr_dstsubtype, &fp->fr_dlookup, &fp->fr_dstfunc); if (fp->fr_dstptr == NULL) return ESRCH; break; #endif default : break; } break; case FR_T_NONE : break; case FR_T_CALLFUNC : break; case FR_T_COMPIPF : break; default : if (makecopy && fp->fr_data != NULL) { KFREES(fp->fr_data, fp->fr_dsize); } return EINVAL; } /* * Lookup all the interface names that are part of the rule. */ frsynclist(fp, NULL); fp->fr_statecnt = 0; /* * Look for an existing matching filter rule, but don't include the * next or interface pointer in the comparison (fr_next, fr_ifa). * This elminates rules which are indentical being loaded. Checksum * the constant part of the filter rule to make comparisons quicker * (this meaning no pointers are included). */ for (fp->fr_cksum = 0, p = (u_int *)&fp->fr_func, pp = &fp->fr_cksum; p < pp; p++) fp->fr_cksum += *p; pp = (u_int *)(fp->fr_caddr + fp->fr_dsize); for (p = (u_int *)fp->fr_data; p < pp; p++) fp->fr_cksum += *p; WRITE_ENTER(&ipf_mutex); /* * Now that the filter rule lists are locked, we can walk the * chain of them without fear. */ ftail = fprev; for (f = *ftail; (f = *ftail) != NULL; ftail = &f->fr_next) { if (fp->fr_collect <= f->fr_collect) { ftail = fprev; f = NULL; break; } fprev = ftail; } bzero((char *)frcache, sizeof(frcache)); for (; (f = *ftail) != NULL; ftail = &f->fr_next) { if ((fp->fr_cksum != f->fr_cksum) || (f->fr_dsize != fp->fr_dsize)) continue; if (bcmp((char *)&f->fr_func, (char *)&fp->fr_func, FR_CMPSIZ)) continue; if ((!ptr && !f->fr_data) || (ptr && f->fr_data && !bcmp((char *)ptr, (char *)f->fr_data, f->fr_dsize))) break; } /* * If zero'ing statistics, copy current to caller and zero. */ if (req == (ioctlcmd_t)SIOCZRLST) { if (f == NULL) error = ESRCH; else { /* * Copy and reduce lock because of impending copyout. * Well we should, but if we do then the atomicity of * this call and the correctness of fr_hits and * fr_bytes cannot be guaranteed. As it is, this code * only resets them to 0 if they are successfully * copied out into user space. */ bcopy((char *)f, (char *)fp, sizeof(*f)); /* MUTEX_DOWNGRADE(&ipf_mutex); */ /* * When we copy this rule back out, set the data * pointer to be what it was in user space. */ fp->fr_data = uptr; error = fr_outobj(data, fp, IPFOBJ_FRENTRY); if (error == 0) { if ((f->fr_dsize != 0) && (uptr != NULL)) error = COPYOUT(f->fr_data, uptr, f->fr_dsize); if (error != 0) error = EFAULT; if (error == 0) { f->fr_hits = 0; f->fr_bytes = 0; } } } if ((ptr != NULL) && (makecopy != 0)) { KFREES(ptr, fp->fr_dsize); } RWLOCK_EXIT(&ipf_mutex); return error; } if (!f) { /* * At the end of this, ftail must point to the place where the * new rule is to be saved/inserted/added. * For SIOCAD*FR, this should be the last rule in the group of * rules that have equal fr_collect fields. * For SIOCIN*FR, ... */ if (req == (ioctlcmd_t)SIOCADAFR || req == (ioctlcmd_t)SIOCADIFR) { for (ftail = fprev; (f = *ftail) != NULL; ) { if (f->fr_collect > fp->fr_collect) break; ftail = &f->fr_next; } f = NULL; ptr = NULL; error = 0; } else if (req == (ioctlcmd_t)SIOCINAFR || req == (ioctlcmd_t)SIOCINIFR) { while ((f = *fprev) != NULL) { if (f->fr_collect >= fp->fr_collect) break; fprev = &f->fr_next; } ftail = fprev; if (fp->fr_hits != 0) { while (fp->fr_hits && (f = *ftail)) { if (f->fr_collect != fp->fr_collect) break; fprev = ftail; ftail = &f->fr_next; fp->fr_hits--; } } f = NULL; ptr = NULL; error = 0; } } /* * Request to remove a rule. */ if (req == (ioctlcmd_t)SIOCRMAFR || req == (ioctlcmd_t)SIOCRMIFR) { if (!f) error = ESRCH; else { /* * Do not allow activity from user space to interfere * with rules not loaded that way. */ if ((makecopy == 1) && !(f->fr_flags & FR_COPIED)) { error = EPERM; goto done; } /* * Return EBUSY if the rule is being reference by * something else (eg state information.) */ if (f->fr_ref > 1) { error = EBUSY; goto done; } #ifdef IPFILTER_SCAN if (f->fr_isctag[0] != '\0' && (f->fr_isc != (struct ipscan *)-1)) ipsc_detachfr(f); #endif if (unit == IPL_LOGAUTH) { error = fr_preauthcmd(req, f, ftail); goto done; } if (*f->fr_grhead != '\0') fr_delgroup(f->fr_grhead, unit, set); fr_fixskip(ftail, f, -1); *ftail = f->fr_next; f->fr_next = NULL; (void) fr_derefrule(&f); } } else { /* * Not removing, so we must be adding/inserting a rule. */ if (f) error = EEXIST; else { if (unit == IPL_LOGAUTH) { error = fr_preauthcmd(req, fp, ftail); goto done; } if (makecopy) { KMALLOC(f, frentry_t *); } else f = fp; if (f != NULL) { if (fp != f) bcopy((char *)fp, (char *)f, sizeof(*f)); MUTEX_NUKE(&f->fr_lock); MUTEX_INIT(&f->fr_lock, "filter rule lock"); #ifdef IPFILTER_SCAN if (f->fr_isctag[0] != '\0' && ipsc_attachfr(f)) f->fr_isc = (struct ipscan *)-1; #endif f->fr_hits = 0; if (makecopy != 0) f->fr_ref = 1; f->fr_next = *ftail; *ftail = f; if (req == (ioctlcmd_t)SIOCINIFR || req == (ioctlcmd_t)SIOCINAFR) fr_fixskip(ftail, f, 1); f->fr_grp = NULL; group = f->fr_grhead; if (*group != '\0') { fg = fr_addgroup(group, f, f->fr_flags, unit, set); if (fg != NULL) f->fr_grp = &fg->fg_start; } } else error = ENOMEM; } } done: RWLOCK_EXIT(&ipf_mutex); if ((ptr != NULL) && (error != 0) && (makecopy != 0)) { KFREES(ptr, fp->fr_dsize); } return (error); } /* ------------------------------------------------------------------------ */ /* Function: fr_funcinit */ /* Returns: int - 0 == success, else ESRCH: cannot resolve rule details */ /* Parameters: fr(I) - pointer to filter rule */ /* */ /* If a rule is a call rule, then check if the function it points to needs */ /* an init function to be called now the rule has been loaded. */ /* ------------------------------------------------------------------------ */ static int fr_funcinit(fr) frentry_t *fr; { ipfunc_resolve_t *ft; int err; err = ESRCH; for (ft = fr_availfuncs; ft->ipfu_addr != NULL; ft++) if (ft->ipfu_addr == fr->fr_func) { err = 0; if (ft->ipfu_init != NULL) err = (*ft->ipfu_init)(fr); break; } return err; } /* ------------------------------------------------------------------------ */ /* Function: fr_findfunc */ /* Returns: ipfunc_t - pointer to function if found, else NULL */ /* Parameters: funcptr(I) - function pointer to lookup */ /* */ /* Look for a function in the table of known functions. */ /* ------------------------------------------------------------------------ */ static ipfunc_t fr_findfunc(funcptr) ipfunc_t funcptr; { ipfunc_resolve_t *ft; for (ft = fr_availfuncs; ft->ipfu_addr != NULL; ft++) if (ft->ipfu_addr == funcptr) return funcptr; return NULL; } /* ------------------------------------------------------------------------ */ /* Function: fr_resolvefunc */ /* Returns: int - 0 == success, else error */ /* Parameters: data(IO) - ioctl data pointer to ipfunc_resolve_t struct */ /* */ /* Copy in a ipfunc_resolve_t structure and then fill in the missing field. */ /* This will either be the function name (if the pointer is set) or the */ /* function pointer if the name is set. When found, fill in the other one */ /* so that the entire, complete, structure can be copied back to user space.*/ /* ------------------------------------------------------------------------ */ int fr_resolvefunc(data) void *data; { ipfunc_resolve_t res, *ft; int err; err = BCOPYIN(data, &res, sizeof(res)); if (err != 0) return EFAULT; if (res.ipfu_addr == NULL && res.ipfu_name[0] != '\0') { for (ft = fr_availfuncs; ft->ipfu_addr != NULL; ft++) if (strncmp(res.ipfu_name, ft->ipfu_name, sizeof(res.ipfu_name)) == 0) { res.ipfu_addr = ft->ipfu_addr; res.ipfu_init = ft->ipfu_init; if (COPYOUT(&res, data, sizeof(res)) != 0) return EFAULT; return 0; } } if (res.ipfu_addr != NULL && res.ipfu_name[0] == '\0') { for (ft = fr_availfuncs; ft->ipfu_addr != NULL; ft++) if (ft->ipfu_addr == res.ipfu_addr) { (void) strncpy(res.ipfu_name, ft->ipfu_name, sizeof(res.ipfu_name)); res.ipfu_init = ft->ipfu_init; if (COPYOUT(&res, data, sizeof(res)) != 0) return EFAULT; return 0; } } return ESRCH; } #if !defined(_KERNEL) || (!defined(__NetBSD__) && !defined(__OpenBSD__) && !defined(__FreeBSD__)) || \ (defined(__FreeBSD__) && (__FreeBSD_version < 501000)) || \ (defined(__NetBSD__) && (__NetBSD_Version__ < 105000000)) || \ (defined(__OpenBSD__) && (OpenBSD < 200006)) /* * From: NetBSD * ppsratecheck(): packets (or events) per second limitation. */ int ppsratecheck(lasttime, curpps, maxpps) struct timeval *lasttime; int *curpps; int maxpps; /* maximum pps allowed */ { struct timeval tv, delta; int rv; GETKTIME(&tv); delta.tv_sec = tv.tv_sec - lasttime->tv_sec; delta.tv_usec = tv.tv_usec - lasttime->tv_usec; if (delta.tv_usec < 0) { delta.tv_sec--; delta.tv_usec += 1000000; } /* * check for 0,0 is so that the message will be seen at least once. * if more than one second have passed since the last update of * lasttime, reset the counter. * * we do increment *curpps even in *curpps < maxpps case, as some may * try to use *curpps for stat purposes as well. */ if ((lasttime->tv_sec == 0 && lasttime->tv_usec == 0) || delta.tv_sec >= 1) { *lasttime = tv; *curpps = 0; rv = 1; } else if (maxpps < 0) rv = 1; else if (*curpps < maxpps) rv = 1; else rv = 0; *curpps = *curpps + 1; return (rv); } #endif /* ------------------------------------------------------------------------ */ /* Function: fr_derefrule */ /* Returns: int - 0 == rule freed up, else rule not freed */ /* Parameters: fr(I) - pointer to filter rule */ /* */ /* Decrement the reference counter to a rule by one. If it reaches zero, */ /* free it and any associated storage space being used by it. */ /* ------------------------------------------------------------------------ */ int fr_derefrule(frp) frentry_t **frp; { frentry_t *fr; fr = *frp; *frp = NULL; MUTEX_ENTER(&fr->fr_lock); fr->fr_ref--; if (fr->fr_ref == 0) { MUTEX_EXIT(&fr->fr_lock); MUTEX_DESTROY(&fr->fr_lock); #ifdef IPFILTER_LOOKUP if (fr->fr_type == FR_T_IPF && fr->fr_satype == FRI_LOOKUP) ip_lookup_deref(fr->fr_srctype, fr->fr_srcptr); if (fr->fr_type == FR_T_IPF && fr->fr_datype == FRI_LOOKUP) ip_lookup_deref(fr->fr_dsttype, fr->fr_dstptr); #endif if (fr->fr_dsize) { KFREES(fr->fr_data, fr->fr_dsize); } if ((fr->fr_flags & FR_COPIED) != 0) { KFREE(fr); return 0; } return 1; } else { MUTEX_EXIT(&fr->fr_lock); } return -1; } #ifdef IPFILTER_LOOKUP /* ------------------------------------------------------------------------ */ /* Function: fr_grpmapinit */ /* Returns: int - 0 == success, else ESRCH because table entry not found*/ /* Parameters: fr(I) - pointer to rule to find hash table for */ /* */ /* Looks for group hash table fr_arg and stores a pointer to it in fr_ptr. */ /* fr_ptr is later used by fr_srcgrpmap and fr_dstgrpmap. */ /* ------------------------------------------------------------------------ */ static int fr_grpmapinit(fr) frentry_t *fr; { char name[FR_GROUPLEN]; iphtable_t *iph; #if defined(SNPRINTF) && defined(_KERNEL) SNPRINTF(name, sizeof(name), "%d", fr->fr_arg); #else (void) sprintf(name, "%d", fr->fr_arg); #endif iph = fr_findhtable(IPL_LOGIPF, name); if (iph == NULL) return ESRCH; if ((iph->iph_flags & FR_INOUT) != (fr->fr_flags & FR_INOUT)) return ESRCH; fr->fr_ptr = iph; return 0; } /* ------------------------------------------------------------------------ */ /* Function: fr_srcgrpmap */ /* Returns: frentry_t * - pointer to "new last matching" rule or NULL */ /* Parameters: fin(I) - pointer to packet information */ /* passp(IO) - pointer to current/new filter decision (unused) */ /* */ /* Look for a rule group head in a hash table, using the source address as */ /* the key, and descend into that group and continue matching rules against */ /* the packet. */ /* ------------------------------------------------------------------------ */ frentry_t *fr_srcgrpmap(fin, passp) fr_info_t *fin; u_32_t *passp; { frgroup_t *fg; void *rval; rval = fr_iphmfindgroup(fin->fin_fr->fr_ptr, &fin->fin_src); if (rval == NULL) return NULL; fg = rval; fin->fin_fr = fg->fg_start; (void) fr_scanlist(fin, *passp); return fin->fin_fr; } /* ------------------------------------------------------------------------ */ /* Function: fr_dstgrpmap */ /* Returns: frentry_t * - pointer to "new last matching" rule or NULL */ /* Parameters: fin(I) - pointer to packet information */ /* passp(IO) - pointer to current/new filter decision (unused) */ /* */ /* Look for a rule group head in a hash table, using the destination */ /* address as the key, and descend into that group and continue matching */ /* rules against the packet. */ /* ------------------------------------------------------------------------ */ frentry_t *fr_dstgrpmap(fin, passp) fr_info_t *fin; u_32_t *passp; { frgroup_t *fg; void *rval; rval = fr_iphmfindgroup(fin->fin_fr->fr_ptr, &fin->fin_dst); if (rval == NULL) return NULL; fg = rval; fin->fin_fr = fg->fg_start; (void) fr_scanlist(fin, *passp); return fin->fin_fr; } #endif /* IPFILTER_LOOKUP */ /* * Queue functions * =============== * These functions manage objects on queues for efficient timeouts. There are * a number of system defined queues as well as user defined timeouts. It is * expected that a lock is held in the domain in which the queue belongs * (i.e. either state or NAT) when calling any of these functions that prevents * fr_freetimeoutqueue() from being called at the same time as any other. */ /* ------------------------------------------------------------------------ */ /* Function: fr_addtimeoutqueue */ /* Returns: struct ifqtq * - NULL if malloc fails, else pointer to */ /* timeout queue with given interval. */ /* Parameters: parent(I) - pointer to pointer to parent node of this list */ /* of interface queues. */ /* seconds(I) - timeout value in seconds for this queue. */ /* */ /* This routine first looks for a timeout queue that matches the interval */ /* being requested. If it finds one, increments the reference counter and */ /* returns a pointer to it. If none are found, it allocates a new one and */ /* inserts it at the top of the list. */ /* */ /* Locking. */ /* It is assumed that the caller of this function has an appropriate lock */ /* held (exclusively) in the domain that encompases 'parent'. */ /* ------------------------------------------------------------------------ */ ipftq_t *fr_addtimeoutqueue(parent, seconds) ipftq_t **parent; u_int seconds; { ipftq_t *ifq; u_int period; period = seconds * IPF_HZ_DIVIDE; MUTEX_ENTER(&ipf_timeoutlock); for (ifq = *parent; ifq != NULL; ifq = ifq->ifq_next) { if (ifq->ifq_ttl == period) { /* * Reset the delete flag, if set, so the structure * gets reused rather than freed and reallocated. */ MUTEX_ENTER(&ifq->ifq_lock); ifq->ifq_flags &= ~IFQF_DELETE; ifq->ifq_ref++; MUTEX_EXIT(&ifq->ifq_lock); MUTEX_EXIT(&ipf_timeoutlock); return ifq; } } KMALLOC(ifq, ipftq_t *); if (ifq != NULL) { ifq->ifq_ttl = period; ifq->ifq_head = NULL; ifq->ifq_tail = &ifq->ifq_head; ifq->ifq_next = *parent; ifq->ifq_pnext = parent; ifq->ifq_ref = 1; ifq->ifq_flags = IFQF_USER; *parent = ifq; fr_userifqs++; MUTEX_NUKE(&ifq->ifq_lock); MUTEX_INIT(&ifq->ifq_lock, "ipftq mutex"); } MUTEX_EXIT(&ipf_timeoutlock); return ifq; } /* ------------------------------------------------------------------------ */ /* Function: fr_deletetimeoutqueue */ /* Returns: int - new reference count value of the timeout queue */ /* Parameters: ifq(I) - timeout queue which is losing a reference. */ /* Locks: ifq->ifq_lock */ /* */ /* This routine must be called when we're discarding a pointer to a timeout */ /* queue object, taking care of the reference counter. */ /* */ /* Now that this just sets a DELETE flag, it requires the expire code to */ /* check the list of user defined timeout queues and call the free function */ /* below (currently commented out) to stop memory leaking. It is done this */ /* way because the locking may not be sufficient to safely do a free when */ /* this function is called. */ /* ------------------------------------------------------------------------ */ int fr_deletetimeoutqueue(ifq) ipftq_t *ifq; { ifq->ifq_ref--; if ((ifq->ifq_ref == 0) && ((ifq->ifq_flags & IFQF_USER) != 0)) { ifq->ifq_flags |= IFQF_DELETE; } return ifq->ifq_ref; } /* ------------------------------------------------------------------------ */ /* Function: fr_freetimeoutqueue */ /* Parameters: ifq(I) - timeout queue which is losing a reference. */ /* Returns: Nil */ /* */ /* Locking: */ /* It is assumed that the caller of this function has an appropriate lock */ /* held (exclusively) in the domain that encompases the callers "domain". */ /* The ifq_lock for this structure should not be held. */ /* */ /* Remove a user definde timeout queue from the list of queues it is in and */ /* tidy up after this is done. */ /* ------------------------------------------------------------------------ */ void fr_freetimeoutqueue(ifq) ipftq_t *ifq; { if (((ifq->ifq_flags & IFQF_DELETE) == 0) || (ifq->ifq_ref != 0) || ((ifq->ifq_flags & IFQF_USER) == 0)) { printf("fr_freetimeoutqueue(%lx) flags 0x%x ttl %d ref %d\n", (u_long)ifq, ifq->ifq_flags, ifq->ifq_ttl, ifq->ifq_ref); return; } /* * Remove from its position in the list. */ *ifq->ifq_pnext = ifq->ifq_next; if (ifq->ifq_next != NULL) ifq->ifq_next->ifq_pnext = ifq->ifq_pnext; MUTEX_DESTROY(&ifq->ifq_lock); ATOMIC_DEC(fr_userifqs); KFREE(ifq); } /* ------------------------------------------------------------------------ */ /* Function: fr_deletequeueentry */ /* Returns: Nil */ /* Parameters: tqe(I) - timeout queue entry to delete */ /* ifq(I) - timeout queue to remove entry from */ /* */ /* Remove a tail queue entry from its queue and make it an orphan. */ /* fr_deletetimeoutqueue is called to make sure the reference count on the */ /* queue is correct. We can't, however, call fr_freetimeoutqueue because */ /* the correct lock(s) may not be held that would make it safe to do so. */ /* ------------------------------------------------------------------------ */ void fr_deletequeueentry(tqe) ipftqent_t *tqe; { ipftq_t *ifq; ifq = tqe->tqe_ifq; MUTEX_ENTER(&ifq->ifq_lock); if (tqe->tqe_pnext != NULL) { *tqe->tqe_pnext = tqe->tqe_next; if (tqe->tqe_next != NULL) tqe->tqe_next->tqe_pnext = tqe->tqe_pnext; else /* we must be the tail anyway */ ifq->ifq_tail = tqe->tqe_pnext; tqe->tqe_pnext = NULL; tqe->tqe_ifq = NULL; } (void) fr_deletetimeoutqueue(ifq); MUTEX_EXIT(&ifq->ifq_lock); } /* ------------------------------------------------------------------------ */ /* Function: fr_queuefront */ /* Returns: Nil */ /* Parameters: tqe(I) - pointer to timeout queue entry */ /* */ /* Move a queue entry to the front of the queue, if it isn't already there. */ /* ------------------------------------------------------------------------ */ void fr_queuefront(tqe) ipftqent_t *tqe; { ipftq_t *ifq; ifq = tqe->tqe_ifq; if (ifq == NULL) return; MUTEX_ENTER(&ifq->ifq_lock); if (ifq->ifq_head != tqe) { *tqe->tqe_pnext = tqe->tqe_next; if (tqe->tqe_next) tqe->tqe_next->tqe_pnext = tqe->tqe_pnext; else ifq->ifq_tail = tqe->tqe_pnext; tqe->tqe_next = ifq->ifq_head; ifq->ifq_head->tqe_pnext = &tqe->tqe_next; ifq->ifq_head = tqe; tqe->tqe_pnext = &ifq->ifq_head; } MUTEX_EXIT(&ifq->ifq_lock); } /* ------------------------------------------------------------------------ */ /* Function: fr_queueback */ /* Returns: Nil */ /* Parameters: tqe(I) - pointer to timeout queue entry */ /* */ /* Move a queue entry to the back of the queue, if it isn't already there. */ /* ------------------------------------------------------------------------ */ void fr_queueback(tqe) ipftqent_t *tqe; { ipftq_t *ifq; ifq = tqe->tqe_ifq; if (ifq == NULL) return; tqe->tqe_die = fr_ticks + ifq->ifq_ttl; MUTEX_ENTER(&ifq->ifq_lock); if (tqe->tqe_next != NULL) { /* at the end already ? */ /* * Remove from list */ *tqe->tqe_pnext = tqe->tqe_next; tqe->tqe_next->tqe_pnext = tqe->tqe_pnext; /* * Make it the last entry. */ tqe->tqe_next = NULL; tqe->tqe_pnext = ifq->ifq_tail; *ifq->ifq_tail = tqe; ifq->ifq_tail = &tqe->tqe_next; } MUTEX_EXIT(&ifq->ifq_lock); } /* ------------------------------------------------------------------------ */ /* Function: fr_queueappend */ /* Returns: Nil */ /* Parameters: tqe(I) - pointer to timeout queue entry */ /* ifq(I) - pointer to timeout queue */ /* parent(I) - owing object pointer */ /* */ /* Add a new item to this queue and put it on the very end. */ /* ------------------------------------------------------------------------ */ void fr_queueappend(tqe, ifq, parent) ipftqent_t *tqe; ipftq_t *ifq; void *parent; { MUTEX_ENTER(&ifq->ifq_lock); tqe->tqe_parent = parent; tqe->tqe_pnext = ifq->ifq_tail; *ifq->ifq_tail = tqe; ifq->ifq_tail = &tqe->tqe_next; tqe->tqe_next = NULL; tqe->tqe_ifq = ifq; tqe->tqe_die = fr_ticks + ifq->ifq_ttl; ifq->ifq_ref++; MUTEX_EXIT(&ifq->ifq_lock); } /* ------------------------------------------------------------------------ */ /* Function: fr_movequeue */ /* Returns: Nil */ /* Parameters: tq(I) - pointer to timeout queue information */ /* oifp(I) - old timeout queue entry was on */ /* nifp(I) - new timeout queue to put entry on */ /* */ /* Move a queue entry from one timeout queue to another timeout queue. */ /* If it notices that the current entry is already last and does not need */ /* to move queue, the return. */ /* ------------------------------------------------------------------------ */ void fr_movequeue(tqe, oifq, nifq) ipftqent_t *tqe; ipftq_t *oifq, *nifq; { /* * Is the operation here going to be a no-op ? */ MUTEX_ENTER(&oifq->ifq_lock); if ((oifq != nifq) || (*oifq->ifq_tail != tqe)) { /* * Remove from the old queue */ *tqe->tqe_pnext = tqe->tqe_next; if (tqe->tqe_next) tqe->tqe_next->tqe_pnext = tqe->tqe_pnext; else oifq->ifq_tail = tqe->tqe_pnext; tqe->tqe_next = NULL; /* * If we're moving from one queue to another, release the * lock on the old queue and get a lock on the new queue. * For user defined queues, if we're moving off it, call * delete in case it can now be freed. */ if (oifq != nifq) { tqe->tqe_ifq = NULL; (void) fr_deletetimeoutqueue(oifq); MUTEX_EXIT(&oifq->ifq_lock); MUTEX_ENTER(&nifq->ifq_lock); tqe->tqe_ifq = nifq; nifq->ifq_ref++; } /* * Add to the bottom of the new queue */ tqe->tqe_die = fr_ticks + nifq->ifq_ttl; tqe->tqe_pnext = nifq->ifq_tail; *nifq->ifq_tail = tqe; nifq->ifq_tail = &tqe->tqe_next; } MUTEX_EXIT(&nifq->ifq_lock); } /* ------------------------------------------------------------------------ */ /* Function: fr_updateipid */ /* Returns: int - 0 == success, -1 == error (packet should be droppped) */ /* Parameters: fin(I) - pointer to packet information */ /* */ /* When we are doing NAT, change the IP of every packet to represent a */ /* single sequence of packets coming from the host, hiding any host */ /* specific sequencing that might otherwise be revealed. If the packet is */ /* a fragment, then store the 'new' IPid in the fragment cache and look up */ /* the fragment cache for non-leading fragments. If a non-leading fragment */ /* has no match in the cache, return an error. */ /* ------------------------------------------------------------------------ */ static int fr_updateipid(fin) fr_info_t *fin; { u_short id, ido, sums; u_32_t sumd, sum; ip_t *ip; if (fin->fin_off != 0) { sum = fr_ipid_knownfrag(fin); if (sum == 0xffffffff) return -1; sum &= 0xffff; id = (u_short)sum; } else { id = fr_nextipid(fin); if (fin->fin_off == 0 && (fin->fin_flx & FI_FRAG) != 0) (void) fr_ipid_newfrag(fin, (u_32_t)id); } ip = fin->fin_ip; ido = ntohs(ip->ip_id); if (id == ido) return 0; ip->ip_id = htons(id); CALC_SUMD(ido, id, sumd); /* DESTRUCTIVE MACRO! id,ido change */ sum = (~ntohs(ip->ip_sum)) & 0xffff; sum += sumd; sum = (sum >> 16) + (sum & 0xffff); sum = (sum >> 16) + (sum & 0xffff); sums = ~(u_short)sum; ip->ip_sum = htons(sums); return 0; } #ifdef NEED_FRGETIFNAME /* ------------------------------------------------------------------------ */ /* Function: fr_getifname */ /* Returns: char * - pointer to interface name */ /* Parameters: ifp(I) - pointer to network interface */ /* buffer(O) - pointer to where to store interface name */ /* */ /* Constructs an interface name in the buffer passed. The buffer passed is */ /* expected to be at least LIFNAMSIZ in bytes big. If buffer is passed in */ /* as a NULL pointer then return a pointer to a static array. */ /* ------------------------------------------------------------------------ */ char *fr_getifname(ifp, buffer) struct ifnet *ifp; char *buffer; { static char namebuf[LIFNAMSIZ]; # if defined(MENTAT) || defined(__FreeBSD__) || defined(__osf__) || \ defined(__sgi) || defined(linux) || defined(_AIX51) || \ (defined(sun) && !defined(__SVR4) && !defined(__svr4__)) int unit, space; char temp[20]; char *s; # endif if (buffer == NULL) buffer = namebuf; (void) strncpy(buffer, ifp->if_name, LIFNAMSIZ); buffer[LIFNAMSIZ - 1] = '\0'; # if defined(MENTAT) || defined(__FreeBSD__) || defined(__osf__) || \ defined(__sgi) || defined(_AIX51) || \ (defined(sun) && !defined(__SVR4) && !defined(__svr4__)) for (s = buffer; *s; s++) ; unit = ifp->if_unit; space = LIFNAMSIZ - (s - buffer); if (space > 0) { # if defined(SNPRINTF) && defined(_KERNEL) SNPRINTF(temp, sizeof(temp), "%d", unit); # else (void) sprintf(temp, "%d", unit); # endif (void) strncpy(s, temp, space); } # endif return buffer; } #endif /* ------------------------------------------------------------------------ */ /* Function: fr_ioctlswitch */ /* Returns: int - -1 continue processing, else ioctl return value */ /* Parameters: unit(I) - device unit opened */ /* data(I) - pointer to ioctl data */ /* cmd(I) - ioctl command */ /* mode(I) - mode value */ /* uid(I) - uid making the ioctl call */ /* ctx(I) - pointer to context data */ /* */ /* Based on the value of unit, call the appropriate ioctl handler or return */ /* EIO if ipfilter is not running. Also checks if write perms are req'd */ /* for the device in order to execute the ioctl. */ /* ------------------------------------------------------------------------ */ int fr_ioctlswitch(unit, data, cmd, mode, uid, ctx) int unit, mode, uid; ioctlcmd_t cmd; void *data, *ctx; { int error = 0; switch (unit) { case IPL_LOGIPF : error = fr_ipf_ioctl(data, cmd, mode, uid, ctx); break; case IPL_LOGNAT : if (fr_running > 0) error = fr_nat_ioctl(data, cmd, mode, uid, ctx); else error = EIO; break; case IPL_LOGSTATE : if (fr_running > 0) error = fr_state_ioctl(data, cmd, mode, uid, ctx); else error = EIO; break; case IPL_LOGAUTH : if (fr_running > 0) error = fr_auth_ioctl(data, cmd, mode, uid, ctx); else error = EIO; break; case IPL_LOGSYNC : #ifdef IPFILTER_SYNC if (fr_running > 0) error = fr_sync_ioctl(data, cmd, mode, uid, ctx); else #endif error = EIO; break; case IPL_LOGSCAN : #ifdef IPFILTER_SCAN if (fr_running > 0) error = fr_scan_ioctl(data, cmd, mode, uid, ctx); else #endif error = EIO; break; case IPL_LOGLOOKUP : #ifdef IPFILTER_LOOKUP if (fr_running > 0) error = ip_lookup_ioctl(data, cmd, mode, uid, ctx); else #endif error = EIO; break; default : error = EIO; break; } return error; } /* * This array defines the expected size of objects coming into the kernel * for the various recognised object types. */ static int fr_objbytes[IPFOBJ_COUNT][2] = { { 1, sizeof(struct frentry) }, /* frentry */ { 0, sizeof(struct friostat) }, { 0, sizeof(struct fr_info) }, { 0, sizeof(struct fr_authstat) }, { 0, sizeof(struct ipfrstat) }, { 0, sizeof(struct ipnat) }, { 0, sizeof(struct natstat) }, { 0, sizeof(struct ipstate_save) }, { 1, sizeof(struct nat_save) }, /* nat_save */ { 0, sizeof(struct natlookup) }, { 1, sizeof(struct ipstate) }, /* ipstate */ { 0, sizeof(struct ips_stat) }, { 0, sizeof(struct frauth) }, { 0, sizeof(struct ipftune) }, { 0, sizeof(struct nat) }, /* nat_t */ { 0, sizeof(struct ipfruleiter) }, { 0, sizeof(struct ipfgeniter) }, { 0, sizeof(struct ipftable) }, { 0, sizeof(struct ipflookupiter) }, { 0, sizeof(struct ipftq) * IPF_TCP_NSTATES }, }; /* ------------------------------------------------------------------------ */ /* Function: fr_inobj */ /* Returns: int - 0 = success, else failure */ /* Parameters: data(I) - pointer to ioctl data */ /* ptr(I) - pointer to store real data in */ /* type(I) - type of structure being moved */ /* */ /* Copy in the contents of what the ipfobj_t points to. In future, we */ /* add things to check for version numbers, sizes, etc, to make it backward */ /* compatible at the ABI for user land. */ /* ------------------------------------------------------------------------ */ int fr_inobj(data, ptr, type) void *data; void *ptr; int type; { ipfobj_t obj; int error = 0; if ((type < 0) || (type >= IPFOBJ_COUNT)) return EINVAL; error = BCOPYIN(data, &obj, sizeof(obj)); if (error != 0) return EFAULT; if (obj.ipfo_type != type) return EINVAL; #ifndef IPFILTER_COMPAT if ((fr_objbytes[type][0] & 1) != 0) { if (obj.ipfo_size < fr_objbytes[type][1]) return EINVAL; } else if (obj.ipfo_size != fr_objbytes[type][1]) { return EINVAL; } #else if (obj.ipfo_rev != IPFILTER_VERSION) /* XXX compatibility hook here */ ; if ((fr_objbytes[type][0] & 1) != 0) { if (obj.ipfo_size < fr_objbytes[type][1]) /* XXX compatibility hook here */ return EINVAL; } else if (obj.ipfo_size != fr_objbytes[type][1]) /* XXX compatibility hook here */ return EINVAL; #endif if ((fr_objbytes[type][0] & 1) != 0) { error = COPYIN(obj.ipfo_ptr, ptr, fr_objbytes[type][1]); } else { error = COPYIN(obj.ipfo_ptr, ptr, obj.ipfo_size); } if (error != 0) error = EFAULT; return error; } /* ------------------------------------------------------------------------ */ /* Function: fr_inobjsz */ /* Returns: int - 0 = success, else failure */ /* Parameters: data(I) - pointer to ioctl data */ /* ptr(I) - pointer to store real data in */ /* type(I) - type of structure being moved */ /* sz(I) - size of data to copy */ /* */ /* As per fr_inobj, except the size of the object to copy in is passed in */ /* but it must not be smaller than the size defined for the type and the */ /* type must allow for varied sized objects. The extra requirement here is */ /* that sz must match the size of the object being passed in - this is not */ /* not possible nor required in fr_inobj(). */ /* ------------------------------------------------------------------------ */ int fr_inobjsz(data, ptr, type, sz) void *data; void *ptr; int type, sz; { ipfobj_t obj; int error; if ((type < 0) || (type >= IPFOBJ_COUNT)) return EINVAL; if (((fr_objbytes[type][0] & 1) == 0) || (sz < fr_objbytes[type][1])) return EINVAL; error = BCOPYIN(data, &obj, sizeof(obj)); if (error != 0) return EFAULT; if (obj.ipfo_type != type) return EINVAL; #ifndef IPFILTER_COMPAT if (obj.ipfo_size != sz) return EINVAL; #else if (obj.ipfo_rev != IPFILTER_VERSION) /* XXX compatibility hook here */ ; if (obj.ipfo_size != sz) /* XXX compatibility hook here */ return EINVAL; #endif error = COPYIN(obj.ipfo_ptr, ptr, sz); if (error != 0) error = EFAULT; return error; } /* ------------------------------------------------------------------------ */ /* Function: fr_outobjsz */ /* Returns: int - 0 = success, else failure */ /* Parameters: data(I) - pointer to ioctl data */ /* ptr(I) - pointer to store real data in */ /* type(I) - type of structure being moved */ /* sz(I) - size of data to copy */ /* */ /* As per fr_outobj, except the size of the object to copy out is passed in */ /* but it must not be smaller than the size defined for the type and the */ /* type must allow for varied sized objects. The extra requirement here is */ /* that sz must match the size of the object being passed in - this is not */ /* not possible nor required in fr_outobj(). */ /* ------------------------------------------------------------------------ */ int fr_outobjsz(data, ptr, type, sz) void *data; void *ptr; int type, sz; { ipfobj_t obj; int error; if ((type < 0) || (type >= IPFOBJ_COUNT) || ((fr_objbytes[type][0] & 1) == 0) || (sz < fr_objbytes[type][1])) return EINVAL; error = BCOPYIN(data, &obj, sizeof(obj)); if (error != 0) return EFAULT; if (obj.ipfo_type != type) return EINVAL; #ifndef IPFILTER_COMPAT if (obj.ipfo_size != sz) return EINVAL; #else if (obj.ipfo_rev != IPFILTER_VERSION) /* XXX compatibility hook here */ ; if (obj.ipfo_size != sz) /* XXX compatibility hook here */ return EINVAL; #endif error = COPYOUT(ptr, obj.ipfo_ptr, sz); if (error != 0) error = EFAULT; return error; } /* ------------------------------------------------------------------------ */ /* Function: fr_outobj */ /* Returns: int - 0 = success, else failure */ /* Parameters: data(I) - pointer to ioctl data */ /* ptr(I) - pointer to store real data in */ /* type(I) - type of structure being moved */ /* */ /* Copy out the contents of what ptr is to where ipfobj points to. In */ /* future, we add things to check for version numbers, sizes, etc, to make */ /* it backward compatible at the ABI for user land. */ /* ------------------------------------------------------------------------ */ int fr_outobj(data, ptr, type) void *data; void *ptr; int type; { ipfobj_t obj; int error; if ((type < 0) || (type >= IPFOBJ_COUNT)) return EINVAL; error = BCOPYIN(data, &obj, sizeof(obj)); if (error != 0) return EFAULT; if (obj.ipfo_type != type) return EINVAL; #ifndef IPFILTER_COMPAT if ((fr_objbytes[type][0] & 1) != 0) { if (obj.ipfo_size < fr_objbytes[type][1]) return EINVAL; } else if (obj.ipfo_size != fr_objbytes[type][1]) return EINVAL; #else if (obj.ipfo_rev != IPFILTER_VERSION) /* XXX compatibility hook here */ ; if ((fr_objbytes[type][0] & 1) != 0) { if (obj.ipfo_size < fr_objbytes[type][1]) /* XXX compatibility hook here */ return EINVAL; } else if (obj.ipfo_size != fr_objbytes[type][1]) /* XXX compatibility hook here */ return EINVAL; #endif error = COPYOUT(ptr, obj.ipfo_ptr, obj.ipfo_size); if (error != 0) error = EFAULT; return error; } /* ------------------------------------------------------------------------ */ /* Function: fr_checkl4sum */ /* Returns: int - 0 = good, -1 = bad, 1 = cannot check */ /* Parameters: fin(I) - pointer to packet information */ /* */ /* If possible, calculate the layer 4 checksum for the packet. If this is */ /* not possible, return without indicating a failure or success but in a */ /* way that is ditinguishable. */ /* ------------------------------------------------------------------------ */ int fr_checkl4sum(fin) fr_info_t *fin; { u_short sum, hdrsum, *csump; udphdr_t *udp; int dosum; if ((fin->fin_flx & FI_NOCKSUM) != 0) return 0; if (fin->fin_cksum == 1) return 0; if (fin->fin_cksum == -1) return -1; /* * If the TCP packet isn't a fragment, isn't too short and otherwise * isn't already considered "bad", then validate the checksum. If * this check fails then considered the packet to be "bad". */ if ((fin->fin_flx & (FI_FRAG|FI_SHORT|FI_BAD)) != 0) return 1; csump = NULL; hdrsum = 0; dosum = 0; sum = 0; #if SOLARIS && defined(_KERNEL) && (SOLARIS2 >= 6) && defined(ICK_VALID) if (dohwcksum && ((*fin->fin_mp)->b_ick_flag == ICK_VALID)) { hdrsum = 0; sum = 0; } else { #endif switch (fin->fin_p) { case IPPROTO_TCP : csump = &((tcphdr_t *)fin->fin_dp)->th_sum; dosum = 1; break; case IPPROTO_UDP : udp = fin->fin_dp; if (udp->uh_sum != 0) { csump = &udp->uh_sum; dosum = 1; } break; case IPPROTO_ICMP : csump = &((struct icmp *)fin->fin_dp)->icmp_cksum; dosum = 1; break; default : return 1; /*NOTREACHED*/ } if (csump != NULL) hdrsum = *csump; if (dosum) { sum = fr_cksum(fin->fin_m, fin->fin_ip, fin->fin_p, fin->fin_dp, fin->fin_dlen + fin->fin_hlen); } #if SOLARIS && defined(_KERNEL) && (SOLARIS2 >= 6) && defined(ICK_VALID) } #endif #if !defined(_KERNEL) if (sum == hdrsum) { FR_DEBUG(("checkl4sum: %hx == %hx\n", sum, hdrsum)); } else { FR_DEBUG(("checkl4sum: %hx != %hx\n", sum, hdrsum)); } #endif if (hdrsum == sum) { fin->fin_cksum = 1; return 0; } fin->fin_cksum = -1; return -1; } /* ------------------------------------------------------------------------ */ /* Function: fr_ifpfillv4addr */ /* Returns: int - 0 = address update, -1 = address not updated */ /* Parameters: atype(I) - type of network address update to perform */ /* sin(I) - pointer to source of address information */ /* mask(I) - pointer to source of netmask information */ /* inp(I) - pointer to destination address store */ /* inpmask(I) - pointer to destination netmask store */ /* */ /* Given a type of network address update (atype) to perform, copy */ /* information from sin/mask into inp/inpmask. If ipnmask is NULL then no */ /* netmask update is performed unless FRI_NETMASKED is passed as atype, in */ /* which case the operation fails. For all values of atype other than */ /* FRI_NETMASKED, if inpmask is non-NULL then the mask is set to an all 1s */ /* value. */ /* ------------------------------------------------------------------------ */ int fr_ifpfillv4addr(atype, sin, mask, inp, inpmask) int atype; struct sockaddr_in *sin, *mask; struct in_addr *inp, *inpmask; { if (inpmask != NULL && atype != FRI_NETMASKED) inpmask->s_addr = 0xffffffff; if (atype == FRI_NETWORK || atype == FRI_NETMASKED) { if (atype == FRI_NETMASKED) { if (inpmask == NULL) return -1; inpmask->s_addr = mask->sin_addr.s_addr; } inp->s_addr = sin->sin_addr.s_addr & mask->sin_addr.s_addr; } else { inp->s_addr = sin->sin_addr.s_addr; } return 0; } #ifdef USE_INET6 /* ------------------------------------------------------------------------ */ /* Function: fr_ifpfillv6addr */ /* Returns: int - 0 = address update, -1 = address not updated */ /* Parameters: atype(I) - type of network address update to perform */ /* sin(I) - pointer to source of address information */ /* mask(I) - pointer to source of netmask information */ /* inp(I) - pointer to destination address store */ /* inpmask(I) - pointer to destination netmask store */ /* */ /* Given a type of network address update (atype) to perform, copy */ /* information from sin/mask into inp/inpmask. If ipnmask is NULL then no */ /* netmask update is performed unless FRI_NETMASKED is passed as atype, in */ /* which case the operation fails. For all values of atype other than */ /* FRI_NETMASKED, if inpmask is non-NULL then the mask is set to an all 1s */ /* value. */ /* ------------------------------------------------------------------------ */ int fr_ifpfillv6addr(atype, sin, mask, inp, inpmask) int atype; struct sockaddr_in6 *sin, *mask; struct in_addr *inp, *inpmask; { i6addr_t *src, *dst, *and, *dmask; src = (i6addr_t *)&sin->sin6_addr; and = (i6addr_t *)&mask->sin6_addr; dst = (i6addr_t *)inp; dmask = (i6addr_t *)inpmask; if (inpmask != NULL && atype != FRI_NETMASKED) { dmask->i6[0] = 0xffffffff; dmask->i6[1] = 0xffffffff; dmask->i6[2] = 0xffffffff; dmask->i6[3] = 0xffffffff; } if (atype == FRI_NETWORK || atype == FRI_NETMASKED) { if (atype == FRI_NETMASKED) { if (inpmask == NULL) return -1; dmask->i6[0] = and->i6[0]; dmask->i6[1] = and->i6[1]; dmask->i6[2] = and->i6[2]; dmask->i6[3] = and->i6[3]; } dst->i6[0] = src->i6[0] & and->i6[0]; dst->i6[1] = src->i6[1] & and->i6[1]; dst->i6[2] = src->i6[2] & and->i6[2]; dst->i6[3] = src->i6[3] & and->i6[3]; } else { dst->i6[0] = src->i6[0]; dst->i6[1] = src->i6[1]; dst->i6[2] = src->i6[2]; dst->i6[3] = src->i6[3]; } return 0; } #endif /* ------------------------------------------------------------------------ */ /* Function: fr_matchtag */ /* Returns: 0 == mismatch, 1 == match. */ /* Parameters: tag1(I) - pointer to first tag to compare */ /* tag2(I) - pointer to second tag to compare */ /* */ /* Returns true (non-zero) or false(0) if the two tag structures can be */ /* considered to be a match or not match, respectively. The tag is 16 */ /* bytes long (16 characters) but that is overlayed with 4 32bit ints so */ /* compare the ints instead, for speed. tag1 is the master of the */ /* comparison. This function should only be called with both tag1 and tag2 */ /* as non-NULL pointers. */ /* ------------------------------------------------------------------------ */ int fr_matchtag(tag1, tag2) ipftag_t *tag1, *tag2; { if (tag1 == tag2) return 1; if ((tag1->ipt_num[0] == 0) && (tag2->ipt_num[0] == 0)) return 1; if ((tag1->ipt_num[0] == tag2->ipt_num[0]) && (tag1->ipt_num[1] == tag2->ipt_num[1]) && (tag1->ipt_num[2] == tag2->ipt_num[2]) && (tag1->ipt_num[3] == tag2->ipt_num[3])) return 1; return 0; } /* ------------------------------------------------------------------------ */ /* Function: fr_coalesce */ /* Returns: 1 == success, -1 == failure, 0 == no change */ /* Parameters: fin(I) - pointer to packet information */ /* */ /* Attempt to get all of the packet data into a single, contiguous buffer. */ /* If this call returns a failure then the buffers have also been freed. */ /* ------------------------------------------------------------------------ */ int fr_coalesce(fin) fr_info_t *fin; { if ((fin->fin_flx & FI_COALESCE) != 0) return 1; /* * If the mbuf pointers indicate that there is no mbuf to work with, * return but do not indicate success or failure. */ if (fin->fin_m == NULL || fin->fin_mp == NULL) return 0; #if defined(_KERNEL) if (fr_pullup(fin->fin_m, fin, fin->fin_plen) == NULL) { ATOMIC_INCL(fr_badcoalesces[fin->fin_out]); # ifdef MENTAT FREE_MB_T(*fin->fin_mp); # endif *fin->fin_mp = NULL; fin->fin_m = NULL; return -1; } #else fin = fin; /* LINT */ #endif return 1; } /* * The following table lists all of the tunable variables that can be * accessed via SIOCIPFGET/SIOCIPFSET/SIOCIPFGETNEXt. The format of each row * in the table below is as follows: * * pointer to value, name of value, minimum, maximum, size of the value's * container, value attribute flags * * For convienience, IPFT_RDONLY means the value is read-only, IPFT_WRDISABLED * means the value can only be written to when IPFilter is loaded but disabled. * The obvious implication is if neither of these are set then the value can be * changed at any time without harm. */ ipftuneable_t ipf_tuneables[] = { /* filtering */ { { &fr_flags }, "fr_flags", 0, 0xffffffff, sizeof(fr_flags), 0, NULL }, { { &fr_active }, "fr_active", 0, 0, sizeof(fr_active), IPFT_RDONLY, NULL }, { { &fr_control_forwarding }, "fr_control_forwarding", 0, 1, sizeof(fr_control_forwarding), 0, NULL }, { { &fr_update_ipid }, "fr_update_ipid", 0, 1, sizeof(fr_update_ipid), 0, NULL }, { { &fr_chksrc }, "fr_chksrc", 0, 1, sizeof(fr_chksrc), 0, NULL }, { { &fr_minttl }, "fr_minttl", 0, 1, sizeof(fr_minttl), 0, NULL }, { { &fr_icmpminfragmtu }, "fr_icmpminfragmtu", 0, 1, sizeof(fr_icmpminfragmtu), 0, NULL }, { { &fr_pass }, "fr_pass", 0, 0xffffffff, sizeof(fr_pass), 0, NULL }, /* state */ { { &fr_tcpidletimeout }, "fr_tcpidletimeout", 1, 0x7fffffff, sizeof(fr_tcpidletimeout), IPFT_WRDISABLED, NULL }, { { &fr_tcpclosewait }, "fr_tcpclosewait", 1, 0x7fffffff, sizeof(fr_tcpclosewait), IPFT_WRDISABLED, NULL }, { { &fr_tcplastack }, "fr_tcplastack", 1, 0x7fffffff, sizeof(fr_tcplastack), IPFT_WRDISABLED, NULL }, { { &fr_tcptimeout }, "fr_tcptimeout", 1, 0x7fffffff, sizeof(fr_tcptimeout), IPFT_WRDISABLED, NULL }, { { &fr_tcpclosed }, "fr_tcpclosed", 1, 0x7fffffff, sizeof(fr_tcpclosed), IPFT_WRDISABLED, NULL }, { { &fr_tcphalfclosed }, "fr_tcphalfclosed", 1, 0x7fffffff, sizeof(fr_tcphalfclosed), IPFT_WRDISABLED, NULL }, { { &fr_udptimeout }, "fr_udptimeout", 1, 0x7fffffff, sizeof(fr_udptimeout), IPFT_WRDISABLED, NULL }, { { &fr_udpacktimeout }, "fr_udpacktimeout", 1, 0x7fffffff, sizeof(fr_udpacktimeout), IPFT_WRDISABLED, NULL }, { { &fr_icmptimeout }, "fr_icmptimeout", 1, 0x7fffffff, sizeof(fr_icmptimeout), IPFT_WRDISABLED, NULL }, { { &fr_icmpacktimeout }, "fr_icmpacktimeout", 1, 0x7fffffff, sizeof(fr_icmpacktimeout), IPFT_WRDISABLED, NULL }, { { &fr_iptimeout }, "fr_iptimeout", 1, 0x7fffffff, sizeof(fr_iptimeout), IPFT_WRDISABLED, NULL }, { { &fr_statemax }, "fr_statemax", 1, 0x7fffffff, sizeof(fr_statemax), 0, NULL }, { { &fr_statesize }, "fr_statesize", 1, 0x7fffffff, sizeof(fr_statesize), IPFT_WRDISABLED, NULL }, { { &fr_state_lock }, "fr_state_lock", 0, 1, sizeof(fr_state_lock), IPFT_RDONLY, NULL }, { { &fr_state_maxbucket }, "fr_state_maxbucket", 1, 0x7fffffff, sizeof(fr_state_maxbucket), IPFT_WRDISABLED, NULL }, { { &fr_state_maxbucket_reset }, "fr_state_maxbucket_reset", 0, 1, sizeof(fr_state_maxbucket_reset), IPFT_WRDISABLED, NULL }, { { &ipstate_logging }, "ipstate_logging", 0, 1, sizeof(ipstate_logging), 0, NULL }, /* nat */ { { &fr_nat_lock }, "fr_nat_lock", 0, 1, sizeof(fr_nat_lock), IPFT_RDONLY, NULL }, { { &ipf_nattable_sz }, "ipf_nattable_sz", 1, 0x7fffffff, sizeof(ipf_nattable_sz), IPFT_WRDISABLED, NULL }, { { &ipf_nattable_max }, "ipf_nattable_max", 1, 0x7fffffff, sizeof(ipf_nattable_max), 0, NULL }, { { &ipf_natrules_sz }, "ipf_natrules_sz", 1, 0x7fffffff, sizeof(ipf_natrules_sz), IPFT_WRDISABLED, NULL }, { { &ipf_rdrrules_sz }, "ipf_rdrrules_sz", 1, 0x7fffffff, sizeof(ipf_rdrrules_sz), IPFT_WRDISABLED, NULL }, { { &ipf_hostmap_sz }, "ipf_hostmap_sz", 1, 0x7fffffff, sizeof(ipf_hostmap_sz), IPFT_WRDISABLED, NULL }, { { &fr_nat_maxbucket }, "fr_nat_maxbucket", 1, 0x7fffffff, sizeof(fr_nat_maxbucket), 0, NULL }, { { &fr_nat_maxbucket_reset }, "fr_nat_maxbucket_reset", 0, 1, sizeof(fr_nat_maxbucket_reset), IPFT_WRDISABLED, NULL }, { { &nat_logging }, "nat_logging", 0, 1, sizeof(nat_logging), 0, NULL }, { { &fr_defnatage }, "fr_defnatage", 1, 0x7fffffff, sizeof(fr_defnatage), IPFT_WRDISABLED, NULL }, { { &fr_defnatipage }, "fr_defnatipage", 1, 0x7fffffff, sizeof(fr_defnatipage), IPFT_WRDISABLED, NULL }, { { &fr_defnaticmpage }, "fr_defnaticmpage", 1, 0x7fffffff, sizeof(fr_defnaticmpage), IPFT_WRDISABLED, NULL }, { { &fr_nat_doflush }, "fr_nat_doflush", 0, 1, sizeof(fr_nat_doflush), 0, NULL }, /* proxy */ { { &ipf_proxy_debug }, "ipf_proxy_debug", 0, 10, sizeof(ipf_proxy_debug), 0, 0 }, /* frag */ { { &ipfr_size }, "ipfr_size", 1, 0x7fffffff, sizeof(ipfr_size), IPFT_WRDISABLED, NULL }, { { &fr_ipfrttl }, "fr_ipfrttl", 1, 0x7fffffff, sizeof(fr_ipfrttl), IPFT_WRDISABLED, NULL }, #ifdef IPFILTER_LOG /* log */ { { &ipl_suppress }, "ipl_suppress", 0, 1, sizeof(ipl_suppress), 0, NULL }, { { &ipl_logmax }, "ipl_logmax", 0, 0x7fffffff, sizeof(ipl_logmax), IPFT_WRDISABLED, NULL }, { { &ipl_logall }, "ipl_logall", 0, 1, sizeof(ipl_logall), 0, NULL }, { { &ipl_logsize }, "ipl_logsize", 0, 0x80000, sizeof(ipl_logsize), 0, NULL }, #endif { { NULL }, NULL, 0, 0, 0, 0, NULL } }; static ipftuneable_t *ipf_tunelist = NULL; /* ------------------------------------------------------------------------ */ /* Function: fr_findtunebycookie */ /* Returns: NULL = search failed, else pointer to tune struct */ /* Parameters: cookie(I) - cookie value to search for amongst tuneables */ /* next(O) - pointer to place to store the cookie for the */ /* "next" tuneable, if it is desired. */ /* */ /* This function is used to walk through all of the existing tunables with */ /* successive calls. It searches the known tunables for the one which has */ /* a matching value for "cookie" - ie its address. When returning a match, */ /* the next one to be found may be returned inside next. */ /* ------------------------------------------------------------------------ */ static ipftuneable_t *fr_findtunebycookie(cookie, next) void *cookie, **next; { ipftuneable_t *ta, **tap; for (ta = ipf_tuneables; ta->ipft_name != NULL; ta++) if (ta == cookie) { if (next != NULL) { /* * If the next entry in the array has a name * present, then return a pointer to it for * where to go next, else return a pointer to * the dynaminc list as a key to search there * next. This facilitates a weak linking of * the two "lists" together. */ if ((ta + 1)->ipft_name != NULL) *next = ta + 1; else *next = &ipf_tunelist; } return ta; } for (tap = &ipf_tunelist; (ta = *tap) != NULL; tap = &ta->ipft_next) if (tap == cookie) { if (next != NULL) *next = &ta->ipft_next; return ta; } if (next != NULL) *next = NULL; return NULL; } /* ------------------------------------------------------------------------ */ /* Function: fr_findtunebyname */ /* Returns: NULL = search failed, else pointer to tune struct */ /* Parameters: name(I) - name of the tuneable entry to find. */ /* */ /* Search the static array of tuneables and the list of dynamic tuneables */ /* for an entry with a matching name. If we can find one, return a pointer */ /* to the matching structure. */ /* ------------------------------------------------------------------------ */ static ipftuneable_t *fr_findtunebyname(name) const char *name; { ipftuneable_t *ta; for (ta = ipf_tuneables; ta->ipft_name != NULL; ta++) if (!strcmp(ta->ipft_name, name)) { return ta; } for (ta = ipf_tunelist; ta != NULL; ta = ta->ipft_next) if (!strcmp(ta->ipft_name, name)) { return ta; } return NULL; } /* ------------------------------------------------------------------------ */ /* Function: fr_addipftune */ /* Returns: int - 0 == success, else failure */ /* Parameters: newtune - pointer to new tune struct to add to tuneables */ /* */ /* Appends the tune structure pointer to by "newtune" to the end of the */ /* current list of "dynamic" tuneable parameters. Once added, the owner */ /* of the object is not expected to ever change "ipft_next". */ /* ------------------------------------------------------------------------ */ int fr_addipftune(newtune) ipftuneable_t *newtune; { ipftuneable_t *ta, **tap; ta = fr_findtunebyname(newtune->ipft_name); if (ta != NULL) return EEXIST; for (tap = &ipf_tunelist; *tap != NULL; tap = &(*tap)->ipft_next) ; newtune->ipft_next = NULL; *tap = newtune; return 0; } /* ------------------------------------------------------------------------ */ /* Function: fr_delipftune */ /* Returns: int - 0 == success, else failure */ /* Parameters: oldtune - pointer to tune struct to remove from the list of */ /* current dynamic tuneables */ /* */ /* Search for the tune structure, by pointer, in the list of those that are */ /* dynamically added at run time. If found, adjust the list so that this */ /* structure is no longer part of it. */ /* ------------------------------------------------------------------------ */ int fr_delipftune(oldtune) ipftuneable_t *oldtune; { ipftuneable_t *ta, **tap; for (tap = &ipf_tunelist; (ta = *tap) != NULL; tap = &ta->ipft_next) if (ta == oldtune) { *tap = oldtune->ipft_next; oldtune->ipft_next = NULL; return 0; } return ESRCH; } /* ------------------------------------------------------------------------ */ /* Function: fr_ipftune */ /* Returns: int - 0 == success, else failure */ /* Parameters: cmd(I) - ioctl command number */ /* data(I) - pointer to ioctl data structure */ /* */ /* Implement handling of SIOCIPFGETNEXT, SIOCIPFGET and SIOCIPFSET. These */ /* three ioctls provide the means to access and control global variables */ /* within IPFilter, allowing (for example) timeouts and table sizes to be */ /* changed without rebooting, reloading or recompiling. The initialisation */ /* and 'destruction' routines of the various components of ipfilter are all */ /* each responsible for handling their own values being too big. */ /* ------------------------------------------------------------------------ */ int fr_ipftune(cmd, data) ioctlcmd_t cmd; void *data; { ipftuneable_t *ta; ipftune_t tu; void *cookie; int error; error = fr_inobj(data, &tu, IPFOBJ_TUNEABLE); if (error != 0) return error; tu.ipft_name[sizeof(tu.ipft_name) - 1] = '\0'; cookie = tu.ipft_cookie; ta = NULL; switch (cmd) { case SIOCIPFGETNEXT : /* * If cookie is non-NULL, assume it to be a pointer to the last * entry we looked at, so find it (if possible) and return a * pointer to the next one after it. The last entry in the * the table is a NULL entry, so when we get to it, set cookie * to NULL and return that, indicating end of list, erstwhile * if we come in with cookie set to NULL, we are starting anew * at the front of the list. */ if (cookie != NULL) { ta = fr_findtunebycookie(cookie, &tu.ipft_cookie); } else { ta = ipf_tuneables; tu.ipft_cookie = ta + 1; } if (ta != NULL) { /* * Entry found, but does the data pointed to by that * row fit in what we can return? */ if (ta->ipft_sz > sizeof(tu.ipft_un)) return EINVAL; tu.ipft_vlong = 0; if (ta->ipft_sz == sizeof(u_long)) tu.ipft_vlong = *ta->ipft_plong; else if (ta->ipft_sz == sizeof(u_int)) tu.ipft_vint = *ta->ipft_pint; else if (ta->ipft_sz == sizeof(u_short)) tu.ipft_vshort = *ta->ipft_pshort; else if (ta->ipft_sz == sizeof(u_char)) tu.ipft_vchar = *ta->ipft_pchar; tu.ipft_sz = ta->ipft_sz; tu.ipft_min = ta->ipft_min; tu.ipft_max = ta->ipft_max; tu.ipft_flags = ta->ipft_flags; bcopy(ta->ipft_name, tu.ipft_name, MIN(sizeof(tu.ipft_name), strlen(ta->ipft_name) + 1)); } error = fr_outobj(data, &tu, IPFOBJ_TUNEABLE); break; case SIOCIPFGET : case SIOCIPFSET : /* * Search by name or by cookie value for a particular entry * in the tuning paramter table. */ error = ESRCH; if (cookie != NULL) { ta = fr_findtunebycookie(cookie, NULL); if (ta != NULL) error = 0; } else if (tu.ipft_name[0] != '\0') { ta = fr_findtunebyname(tu.ipft_name); if (ta != NULL) error = 0; } if (error != 0) break; if (cmd == (ioctlcmd_t)SIOCIPFGET) { /* * Fetch the tuning parameters for a particular value */ tu.ipft_vlong = 0; if (ta->ipft_sz == sizeof(u_long)) tu.ipft_vlong = *ta->ipft_plong; else if (ta->ipft_sz == sizeof(u_int)) tu.ipft_vint = *ta->ipft_pint; else if (ta->ipft_sz == sizeof(u_short)) tu.ipft_vshort = *ta->ipft_pshort; else if (ta->ipft_sz == sizeof(u_char)) tu.ipft_vchar = *ta->ipft_pchar; tu.ipft_cookie = ta; tu.ipft_sz = ta->ipft_sz; tu.ipft_min = ta->ipft_min; tu.ipft_max = ta->ipft_max; tu.ipft_flags = ta->ipft_flags; error = fr_outobj(data, &tu, IPFOBJ_TUNEABLE); } else if (cmd == (ioctlcmd_t)SIOCIPFSET) { /* * Set an internal parameter. The hard part here is * getting the new value safely and correctly out of * the kernel (given we only know its size, not type.) */ u_long in; if (((ta->ipft_flags & IPFT_WRDISABLED) != 0) && (fr_running > 0)) { error = EBUSY; break; } in = tu.ipft_vlong; if (in < ta->ipft_min || in > ta->ipft_max) { error = EINVAL; break; } if (ta->ipft_sz == sizeof(u_long)) { tu.ipft_vlong = *ta->ipft_plong; *ta->ipft_plong = in; } else if (ta->ipft_sz == sizeof(u_int)) { tu.ipft_vint = *ta->ipft_pint; *ta->ipft_pint = (u_int)(in & 0xffffffff); } else if (ta->ipft_sz == sizeof(u_short)) { tu.ipft_vshort = *ta->ipft_pshort; *ta->ipft_pshort = (u_short)(in & 0xffff); } else if (ta->ipft_sz == sizeof(u_char)) { tu.ipft_vchar = *ta->ipft_pchar; *ta->ipft_pchar = (u_char)(in & 0xff); } error = fr_outobj(data, &tu, IPFOBJ_TUNEABLE); } break; default : error = EINVAL; break; } return error; } /* ------------------------------------------------------------------------ */ /* Function: fr_initialise */ /* Returns: int - 0 == success, < 0 == failure */ /* Parameters: None. */ /* */ /* Call of the initialise functions for all the various subsystems inside */ /* of IPFilter. If any of them should fail, return immeadiately a failure */ /* BUT do not try to recover from the error here. */ /* ------------------------------------------------------------------------ */ int fr_initialise() { int i; bzero(&frstats, sizeof(frstats)); #ifdef IPFILTER_LOG i = fr_loginit(); if (i < 0) return -10 + i; #endif i = fr_natinit(); if (i < 0) return -20 + i; i = fr_stateinit(); if (i < 0) return -30 + i; i = fr_authinit(); if (i < 0) return -40 + i; i = fr_fraginit(); if (i < 0) return -50 + i; i = appr_init(); if (i < 0) return -60 + i; #ifdef IPFILTER_SYNC i = ipfsync_init(); if (i < 0) return -70 + i; #endif #ifdef IPFILTER_SCAN i = ipsc_init(); if (i < 0) return -80 + i; #endif #ifdef IPFILTER_LOOKUP i = ip_lookup_init(); if (i < 0) return -90 + i; #endif #ifdef IPFILTER_COMPILED ipfrule_add(); #endif return 0; } /* ------------------------------------------------------------------------ */ /* Function: fr_deinitialise */ /* Returns: None. */ /* Parameters: None. */ /* */ /* Call all the various subsystem cleanup routines to deallocate memory or */ /* destroy locks or whatever they've done that they need to now undo. */ /* The order here IS important as there are some cross references of */ /* internal data structures. */ /* ------------------------------------------------------------------------ */ void fr_deinitialise() { fr_fragunload(); fr_authunload(); fr_natunload(); fr_stateunload(); #ifdef IPFILTER_SCAN fr_scanunload(); #endif appr_unload(); #ifdef IPFILTER_COMPILED ipfrule_remove(); #endif (void) frflush(IPL_LOGIPF, 0, FR_INQUE|FR_OUTQUE|FR_INACTIVE); (void) frflush(IPL_LOGIPF, 0, FR_INQUE|FR_OUTQUE); (void) frflush(IPL_LOGCOUNT, 0, FR_INQUE|FR_OUTQUE|FR_INACTIVE); (void) frflush(IPL_LOGCOUNT, 0, FR_INQUE|FR_OUTQUE); #ifdef IPFILTER_LOOKUP ip_lookup_unload(); #endif #ifdef IPFILTER_LOG fr_logunload(); #endif } /* ------------------------------------------------------------------------ */ /* Function: fr_zerostats */ /* Returns: int - 0 = success, else failure */ /* Parameters: data(O) - pointer to pointer for copying data back to */ /* */ /* Copies the current statistics out to userspace and then zero's the */ /* current ones in the kernel. The lock is only held across the bzero() as */ /* the copyout may result in paging (ie network activity.) */ /* ------------------------------------------------------------------------ */ int fr_zerostats(data) void *data; { friostat_t fio; int error; fr_getstat(&fio); error = fr_outobj(data, &fio, IPFOBJ_IPFSTAT); if (error) return EFAULT; WRITE_ENTER(&ipf_mutex); bzero(&frstats, sizeof(frstats)); RWLOCK_EXIT(&ipf_mutex); return 0; } /* ------------------------------------------------------------------------ */ /* Function: fr_resolvedest */ /* Returns: Nil */ /* Parameters: fdp(IO) - pointer to destination information to resolve */ /* v(I) - IP protocol version to match */ /* */ /* Looks up an interface name in the frdest structure pointed to by fdp and */ /* if a matching name can be found for the particular IP protocol version */ /* then store the interface pointer in the frdest struct. If no match is */ /* found, then set the interface pointer to be -1 as NULL is considered to */ /* indicate there is no information at all in the structure. */ /* ------------------------------------------------------------------------ */ void fr_resolvedest(fdp, v) frdest_t *fdp; int v; { void *ifp; ifp = NULL; v = v; /* LINT */ if (*fdp->fd_ifname != '\0') { ifp = GETIFP(fdp->fd_ifname, v); if (ifp == NULL) ifp = (void *)-1; } fdp->fd_ifp = ifp; } /* ------------------------------------------------------------------------ */ /* Function: fr_resolvenic */ /* Returns: void* - NULL = wildcard name, -1 = failed to find NIC, else */ /* pointer to interface structure for NIC */ /* Parameters: name(I) - complete interface name */ /* v(I) - IP protocol version */ /* */ /* Look for a network interface structure that firstly has a matching name */ /* to that passed in and that is also being used for that IP protocol */ /* version (necessary on some platforms where there are separate listings */ /* for both IPv4 and IPv6 on the same physical NIC. */ /* */ /* One might wonder why name gets terminated with a \0 byte in here. The */ /* reason is an interface name could get into the kernel structures of ipf */ /* in any number of ways and so long as they all use the same sized array */ /* to put the name in, it makes sense to ensure it gets null terminated */ /* before it is used for its intended purpose - finding its match in the */ /* kernel's list of configured interfaces. */ /* */ /* NOTE: This SHOULD ONLY be used with IPFilter structures that have an */ /* array for the name that is LIFNAMSIZ bytes (at least) in length. */ /* ------------------------------------------------------------------------ */ void *fr_resolvenic(name, v) char *name; int v; { void *nic; if (name[0] == '\0') return NULL; if ((name[1] == '\0') && ((name[0] == '-') || (name[0] == '*'))) { return NULL; } name[LIFNAMSIZ - 1] = '\0'; nic = GETIFP(name, v); if (nic == NULL) nic = (void *)-1; return nic; } ipftoken_t *ipftokenhead = NULL, **ipftokentail = &ipftokenhead; /* ------------------------------------------------------------------------ */ /* Function: ipf_expiretokens */ /* Returns: None. */ /* Parameters: None. */ /* */ /* This function is run every ipf tick to see if there are any tokens that */ /* have been held for too long and need to be freed up. */ /* ------------------------------------------------------------------------ */ void ipf_expiretokens() { ipftoken_t *it; WRITE_ENTER(&ipf_tokens); while ((it = ipftokenhead) != NULL) { if (it->ipt_die > fr_ticks) break; ipf_freetoken(it); } RWLOCK_EXIT(&ipf_tokens); } /* ------------------------------------------------------------------------ */ /* Function: ipf_deltoken */ /* Returns: int - 0 = success, else error */ /* Parameters: type(I) - the token type to match */ /* uid(I) - uid owning the token */ /* ptr(I) - context pointer for the token */ /* */ /* This function looks for a a token in the current list that matches up */ /* the fields (type, uid, ptr). If none is found, ESRCH is returned, else */ /* call ipf_freetoken() to remove it from the list. */ /* ------------------------------------------------------------------------ */ int ipf_deltoken(type, uid, ptr) int type, uid; void *ptr; { ipftoken_t *it; int error = ESRCH; WRITE_ENTER(&ipf_tokens); for (it = ipftokenhead; it != NULL; it = it->ipt_next) if (ptr == it->ipt_ctx && type == it->ipt_type && uid == it->ipt_uid) { ipf_freetoken(it); error = 0; break; } RWLOCK_EXIT(&ipf_tokens); return error; } /* ------------------------------------------------------------------------ */ /* Function: ipf_findtoken */ /* Returns: ipftoken_t * - NULL if no memory, else pointer to token */ /* Parameters: type(I) - the token type to match */ /* uid(I) - uid owning the token */ /* ptr(I) - context pointer for the token */ /* */ /* This function looks for a live token in the list of current tokens that */ /* matches the tuple (type, uid, ptr). If one cannot be found then one is */ /* allocated. If one is found then it is moved to the top of the list of */ /* currently active tokens. */ /* */ /* NOTE: It is by design that this function returns holding a read lock on */ /* ipf_tokens. Callers must make sure they release it! */ /* ------------------------------------------------------------------------ */ ipftoken_t *ipf_findtoken(type, uid, ptr) int type, uid; void *ptr; { ipftoken_t *it, *new; KMALLOC(new, ipftoken_t *); WRITE_ENTER(&ipf_tokens); for (it = ipftokenhead; it != NULL; it = it->ipt_next) { if (it->ipt_alive == 0) continue; if (ptr == it->ipt_ctx && type == it->ipt_type && uid == it->ipt_uid) break; } if (it == NULL) { it = new; new = NULL; if (it == NULL) return NULL; it->ipt_data = NULL; it->ipt_ctx = ptr; it->ipt_uid = uid; it->ipt_type = type; it->ipt_next = NULL; it->ipt_alive = 1; } else { if (new != NULL) { KFREE(new); new = NULL; } ipf_unlinktoken(it); } it->ipt_pnext = ipftokentail; *ipftokentail = it; ipftokentail = &it->ipt_next; it->ipt_next = NULL; it->ipt_die = fr_ticks + 2; MUTEX_DOWNGRADE(&ipf_tokens); return it; } /* ------------------------------------------------------------------------ */ /* Function: ipf_unlinktoken */ /* Returns: None. */ /* Parameters: token(I) - pointer to token structure */ /* */ /* This function unlinks a token structure from the linked list of tokens */ /* that "own" it. The head pointer never needs to be explicitly adjusted */ /* but the tail does due to the linked list implementation. */ /* ------------------------------------------------------------------------ */ static void ipf_unlinktoken(token) ipftoken_t *token; { if (ipftokentail == &token->ipt_next) ipftokentail = token->ipt_pnext; *token->ipt_pnext = token->ipt_next; if (token->ipt_next != NULL) token->ipt_next->ipt_pnext = token->ipt_pnext; } /* ------------------------------------------------------------------------ */ /* Function: ipf_freetoken */ /* Returns: None. */ /* Parameters: token(I) - pointer to token structure */ /* */ /* This function unlinks a token from the linked list and on the path to */ /* free'ing the data, it calls the dereference function that is associated */ /* with the type of data pointed to by the token as it is considered to */ /* hold a reference to it. */ /* ------------------------------------------------------------------------ */ void ipf_freetoken(token) ipftoken_t *token; { void *data, **datap; ipf_unlinktoken(token); data = token->ipt_data; datap = &data; if ((data != NULL) && (data != (void *)-1)) { switch (token->ipt_type) { case IPFGENITER_IPF : (void) fr_derefrule((frentry_t **)datap); break; case IPFGENITER_IPNAT : WRITE_ENTER(&ipf_nat); fr_ipnatderef((ipnat_t **)datap); RWLOCK_EXIT(&ipf_nat); break; case IPFGENITER_NAT : fr_natderef((nat_t **)datap); break; case IPFGENITER_STATE : fr_statederef((ipstate_t **)datap); break; case IPFGENITER_FRAG : #ifdef USE_MUTEXES fr_fragderef((ipfr_t **)datap, &ipf_frag); #else fr_fragderef((ipfr_t **)datap); #endif break; case IPFGENITER_NATFRAG : #ifdef USE_MUTEXES fr_fragderef((ipfr_t **)datap, &ipf_natfrag); #else fr_fragderef((ipfr_t **)datap); #endif break; case IPFGENITER_HOSTMAP : WRITE_ENTER(&ipf_nat); fr_hostmapdel((hostmap_t **)datap); RWLOCK_EXIT(&ipf_nat); break; default : #ifdef IPFILTER_LOOKUP ip_lookup_iterderef(token->ipt_type, data); #endif break; } } KFREE(token); } /* ------------------------------------------------------------------------ */ /* Function: ipf_getnextrule */ /* Returns: int - 0 = success, else error */ /* Parameters: t(I) - pointer to destination information to resolve */ /* ptr(I) - pointer to ipfobj_t to copyin from user space */ /* */ /* This function's first job is to bring in the ipfruleiter_t structure via */ /* the ipfobj_t structure to determine what should be the next rule to */ /* return. Once the ipfruleiter_t has been brought in, it then tries to */ /* find the 'next rule'. This may include searching rule group lists or */ /* just be as simple as looking at the 'next' field in the rule structure. */ /* When we have found the rule to return, increase its reference count and */ /* if we used an existing rule to get here, decrease its reference count. */ /* ------------------------------------------------------------------------ */ int ipf_getnextrule(ipftoken_t *t, void *ptr) { frentry_t *fr, *next, zero; int error, count, out; ipfruleiter_t it; frgroup_t *fg; char *dst; if (t == NULL || ptr == NULL) return EFAULT; error = fr_inobj(ptr, &it, IPFOBJ_IPFITER); if (error != 0) return error; if ((it.iri_inout < 0) || (it.iri_inout > 3)) return EINVAL; if ((it.iri_active != 0) && (it.iri_active != 1)) return EINVAL; if (it.iri_nrules == 0) return ENOSPC; if (it.iri_rule == NULL) return EFAULT; out = it.iri_inout & F_OUT; fr = t->ipt_data; READ_ENTER(&ipf_mutex); if (fr == NULL) { if (*it.iri_group == '\0') { if ((it.iri_inout & F_ACIN) != 0) { if (it.iri_v == 4) next = ipacct[out][it.iri_active]; else next = ipacct6[out][it.iri_active]; } else { if (it.iri_v == 4) next = ipfilter[out][it.iri_active]; else next = ipfilter6[out][it.iri_active]; } } else { fg = fr_findgroup(it.iri_group, IPL_LOGIPF, it.iri_active, NULL); if (fg != NULL) next = fg->fg_start; else next = NULL; } } else { next = fr->fr_next; } dst = (char *)it.iri_rule; count = it.iri_nrules; /* * The ipfruleiter may ask for more than 1 rule at a time to be * copied out, so long as that many exist in the list to start with! */ for (;;) { if (next != NULL) { if (count == 1) { MUTEX_ENTER(&next->fr_lock); next->fr_ref++; MUTEX_EXIT(&next->fr_lock); t->ipt_data = next; } } else { bzero(&zero, sizeof(zero)); next = &zero; count = 1; t->ipt_data = NULL; } RWLOCK_EXIT(&ipf_mutex); error = COPYOUT(next, dst, sizeof(*next)); if (error != 0) return EFAULT; if (next->fr_data != NULL) { dst += sizeof(*next); error = COPYOUT(next->fr_data, dst, next->fr_dsize); if (error != 0) error = EFAULT; else dst += next->fr_dsize; } if ((count == 1) || (error != 0)) break; count--; READ_ENTER(&ipf_mutex); next = next->fr_next; } if (fr != NULL) { (void) fr_derefrule(&fr); } return error; } /* ------------------------------------------------------------------------ */ /* Function: fr_frruleiter */ /* Returns: int - 0 = success, else error */ /* Parameters: data(I) - the token type to match */ /* uid(I) - uid owning the token */ /* ptr(I) - context pointer for the token */ /* */ /* This function serves as a stepping stone between fr_ipf_ioctl and */ /* ipf_getnextrule. It's role is to find the right token in the kernel for */ /* the process doing the ioctl and use that to ask for the next rule. */ /* ------------------------------------------------------------------------ */ static int ipf_frruleiter(data, uid, ctx) void *data, *ctx; int uid; { ipftoken_t *token; int error; token = ipf_findtoken(IPFGENITER_IPF, uid, ctx); if (token != NULL) error = ipf_getnextrule(token, data); else error = EFAULT; RWLOCK_EXIT(&ipf_tokens); return error; } /* ------------------------------------------------------------------------ */ /* Function: fr_geniter */ /* Returns: int - 0 = success, else error */ /* Parameters: token(I) - pointer to ipftoken_t structure */ /* itp(I) - */ /* */ /* ------------------------------------------------------------------------ */ static int ipf_geniter(token, itp) ipftoken_t *token; ipfgeniter_t *itp; { int error; switch (itp->igi_type) { case IPFGENITER_FRAG : #ifdef USE_MUTEXES error = fr_nextfrag(token, itp, &ipfr_list, &ipfr_tail, &ipf_frag); #else error = fr_nextfrag(token, itp, &ipfr_list, &ipfr_tail); #endif break; default : error = EINVAL; break; } return error; } /* ------------------------------------------------------------------------ */ /* Function: fr_genericiter */ /* Returns: int - 0 = success, else error */ /* Parameters: data(I) - the token type to match */ /* uid(I) - uid owning the token */ /* ptr(I) - context pointer for the token */ /* */ /* ------------------------------------------------------------------------ */ int ipf_genericiter(data, uid, ctx) void *data, *ctx; int uid; { ipftoken_t *token; ipfgeniter_t iter; int error; error = fr_inobj(data, &iter, IPFOBJ_GENITER); if (error != 0) return error; token = ipf_findtoken(iter.igi_type, uid, ctx); if (token != NULL) { token->ipt_subtype = iter.igi_type; error = ipf_geniter(token, &iter); } else error = EFAULT; RWLOCK_EXIT(&ipf_tokens); return error; } /* ------------------------------------------------------------------------ */ /* Function: fr_ipf_ioctl */ /* Returns: int - 0 = success, else error */ /* Parameters: data(I) - the token type to match */ /* cmd(I) - the ioctl command number */ /* mode(I) - mode flags for the ioctl */ /* uid(I) - uid owning the token */ /* ptr(I) - context pointer for the token */ /* */ /* This function handles all of the ioctl command that are actually isssued */ /* to the /dev/ipl device. */ /* ------------------------------------------------------------------------ */ int fr_ipf_ioctl(data, cmd, mode, uid, ctx) caddr_t data; ioctlcmd_t cmd; int mode, uid; void *ctx; { friostat_t fio; int error, tmp; SPL_INT(s); switch (cmd) { case SIOCFRENB : if (!(mode & FWRITE)) error = EPERM; else { error = BCOPYIN(data, &tmp, sizeof(tmp)); if (error != 0) { error = EFAULT; break; } RWLOCK_EXIT(&ipf_global); WRITE_ENTER(&ipf_global); if (tmp) { if (fr_running > 0) error = 0; else error = ipfattach(); if (error == 0) fr_running = 1; else (void) ipfdetach(); } else { error = ipfdetach(); if (error == 0) fr_running = -1; } } break; case SIOCIPFSET : if (!(mode & FWRITE)) { error = EPERM; break; } /* FALLTHRU */ case SIOCIPFGETNEXT : case SIOCIPFGET : error = fr_ipftune(cmd, (void *)data); break; case SIOCSETFF : if (!(mode & FWRITE)) error = EPERM; else { error = BCOPYIN(data, &fr_flags, sizeof(fr_flags)); if (error != 0) error = EFAULT; } break; case SIOCGETFF : error = BCOPYOUT(&fr_flags, data, sizeof(fr_flags)); if (error != 0) error = EFAULT; break; case SIOCFUNCL : error = fr_resolvefunc((void *)data); break; case SIOCINAFR : case SIOCRMAFR : case SIOCADAFR : case SIOCZRLST : if (!(mode & FWRITE)) error = EPERM; else error = frrequest(IPL_LOGIPF, cmd, data, fr_active, 1); break; case SIOCINIFR : case SIOCRMIFR : case SIOCADIFR : if (!(mode & FWRITE)) error = EPERM; else error = frrequest(IPL_LOGIPF, cmd, data, 1 - fr_active, 1); break; case SIOCSWAPA : if (!(mode & FWRITE)) error = EPERM; else { WRITE_ENTER(&ipf_mutex); bzero((char *)frcache, sizeof(frcache[0]) * 2); error = BCOPYOUT(&fr_active, data, sizeof(fr_active)); if (error != 0) error = EFAULT; else fr_active = 1 - fr_active; RWLOCK_EXIT(&ipf_mutex); } break; case SIOCGETFS : fr_getstat(&fio); error = fr_outobj((void *)data, &fio, IPFOBJ_IPFSTAT); break; case SIOCFRZST : if (!(mode & FWRITE)) error = EPERM; else error = fr_zerostats(data); break; case SIOCIPFFL : if (!(mode & FWRITE)) error = EPERM; else { error = BCOPYIN(data, &tmp, sizeof(tmp)); if (!error) { tmp = frflush(IPL_LOGIPF, 4, tmp); error = BCOPYOUT(&tmp, data, sizeof(tmp)); if (error != 0) error = EFAULT; } else error = EFAULT; } break; #ifdef USE_INET6 case SIOCIPFL6 : if (!(mode & FWRITE)) error = EPERM; else { error = BCOPYIN(data, &tmp, sizeof(tmp)); if (!error) { tmp = frflush(IPL_LOGIPF, 6, tmp); error = BCOPYOUT(&tmp, data, sizeof(tmp)); if (error != 0) error = EFAULT; } else error = EFAULT; } break; #endif case SIOCSTLCK : error = BCOPYIN(data, &tmp, sizeof(tmp)); if (error == 0) { fr_state_lock = tmp; fr_nat_lock = tmp; fr_frag_lock = tmp; fr_auth_lock = tmp; } else error = EFAULT; break; #ifdef IPFILTER_LOG case SIOCIPFFB : if (!(mode & FWRITE)) error = EPERM; else { tmp = ipflog_clear(IPL_LOGIPF); error = BCOPYOUT(&tmp, data, sizeof(tmp)); if (error) error = EFAULT; } break; #endif /* IPFILTER_LOG */ case SIOCFRSYN : if (!(mode & FWRITE)) error = EPERM; else { RWLOCK_EXIT(&ipf_global); WRITE_ENTER(&ipf_global); #ifdef MENTAT error = ipfsync(); #else frsync(NULL); error = 0; #endif } break; case SIOCGFRST : error = fr_outobj((void *)data, fr_fragstats(), IPFOBJ_FRAGSTAT); break; #ifdef IPFILTER_LOG case FIONREAD : tmp = (int)iplused[IPL_LOGIPF]; error = BCOPYOUT(&tmp, data, sizeof(tmp)); break; #endif case SIOCIPFITER : SPL_SCHED(s); error = ipf_frruleiter(data, uid, ctx); SPL_X(s); break; case SIOCGENITER : SPL_SCHED(s); error = ipf_genericiter(data, uid, ctx); SPL_X(s); break; case SIOCIPFDELTOK : SPL_SCHED(s); error = BCOPYIN(data, &tmp, sizeof(tmp)); if (error == 0) error = ipf_deltoken(tmp, uid, ctx); SPL_X(s); break; default : error = EINVAL; break; } return error; } /* ------------------------------------------------------------------------ */ /* Function: ipf_queueflush */ /* Returns: int - number of entries flushed (0 = none) */ /* Parameters: deletefn(I) - function to call to delete entry */ /* ipfqs(I) - top of the list of ipf internal queues */ /* userqs(I) - top of the list of user defined timeouts */ /* */ /* This fucntion gets called when the state/NAT hash tables fill up and we */ /* need to try a bit harder to free up some space. The algorithm used is */ /* to look for the oldest entries on each timeout queue and free them if */ /* they are within the given window we are considering. Where the window */ /* starts and the steps taken to increase its size depend upon how long ipf */ /* has been running (fr_ticks.) Anything modified in the last 30 seconds */ /* is not touched. */ /* touched */ /* die fr_ticks 30*1.5 1800*1.5 | 43200*1.5 */ /* | | | | | | */ /* future <--+----------+--------+-----------+-----+-----+-----------> past */ /* now \_int=30s_/ \_int=1hr_/ \_int=12hr */ /* */ /* Points to note: */ /* - tqe_die is the time, in the future, when entries die. */ /* - tqe_die - fr_ticks is how long left the connection has to live in ipf */ /* ticks. */ /* - tqe_touched is when the entry was last used by NAT/state */ /* - the closer tqe_touched is to fr_ticks, the further tqe_die will be for */ /* any given timeout queue and vice versa. */ /* - both tqe_die and tqe_touched increase over time */ /* - timeout queues are sorted with the highest value of tqe_die at the */ /* bottom and therefore the smallest values of each are at the top */ /* */ /* We start by setting up a maximum range to scan for things to move of */ /* iend (newest) to istart (oldest) in chunks of "interval". If nothing is */ /* found in that range, "interval" is adjusted (so long as it isn't 30) and */ /* we start again with a new value for "iend" and "istart". The downside */ /* of the current implementation is that it may return removing just 1 entry*/ /* every time (pathological case) where it could remove more. */ /* ------------------------------------------------------------------------ */ int ipf_queueflush(deletefn, ipfqs, userqs) ipftq_delete_fn_t deletefn; ipftq_t *ipfqs, *userqs; { u_long interval, istart, iend; ipftq_t *ifq, *ifqnext; ipftqent_t *tqe, *tqn; int removed; /* * NOTE: Use of "* 15 / 10" is required here because if "* 1.5" is * used then the operations are upgraded to floating point * and kernels don't like floating point... */ if (fr_ticks > IPF_TTLVAL(43200 * 15 / 10)) { istart = IPF_TTLVAL(86400 * 4); interval = IPF_TTLVAL(43200); } else if (fr_ticks > IPF_TTLVAL(1800 * 15 / 10)) { istart = IPF_TTLVAL(43200); interval = IPF_TTLVAL(1800); } else if (fr_ticks > IPF_TTLVAL(30 * 15 / 10)) { istart = IPF_TTLVAL(1800); interval = IPF_TTLVAL(30); } else { return 0; } if (istart > fr_ticks) { if (fr_ticks - interval < interval) istart = interval; else istart = (fr_ticks / interval) * interval; } iend = fr_ticks - interval; removed = 0; for (;;) { u_long try; try = fr_ticks - istart; for (ifq = ipfqs; ifq != NULL; ifq = ifq->ifq_next) { for (tqn = ifq->ifq_head; ((tqe = tqn) != NULL); ) { if (try < tqe->tqe_touched) break; tqn = tqe->tqe_next; if ((*deletefn)(tqe->tqe_parent) == 0) removed++; } } for (ifq = userqs; ifq != NULL; ifq = ifqnext) { ifqnext = ifq->ifq_next; for (tqn = ifq->ifq_head; ((tqe = tqn) != NULL); ) { if (try < tqe->tqe_touched) break; tqn = tqe->tqe_next; if ((*deletefn)(tqe->tqe_parent) == 0) removed++; } } if (try >= iend) { if (removed > 0) break; if (interval == IPF_TTLVAL(43200)) { interval = IPF_TTLVAL(1800); } else if (interval == IPF_TTLVAL(1800)) { interval = IPF_TTLVAL(30); } else { break; } if (interval >= fr_ticks) break; iend = fr_ticks - interval; } istart -= interval; } return removed; }