sys/netpfil/ipfw/ip_fw_log.c

   1 /*-
   2  * Copyright (c) 2002-2009 Luigi Rizzo, Universita` di Pisa
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  *
  13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  14  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  16  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  17  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  18  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  19  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  20  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  21  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  23  * SUCH DAMAGE.
  24  */
  25
  26 #include <sys/cdefs.h>
  27 __FBSDID("$FreeBSD$");
  28
  29 /*
  30  * Logging support for ipfw
  31  */
  32
  33 #include "opt_ipfw.h"
  34 #include "opt_inet.h"
  35 #ifndef INET
  36 #error IPFIREWALL requires INET.
  37 #endif /* INET */
  38 #include "opt_inet6.h"
  39
  40 #include <sys/param.h>
  41 #include <sys/systm.h>
  42 #include <sys/kernel.h>
  43 #include <sys/malloc.h>
  44 #include <sys/mbuf.h>
  45 #include <sys/socket.h>
  46 #include <sys/sysctl.h>
  47 #include <sys/syslog.h>
  48 #include <sys/lock.h>
  49 #include <sys/rwlock.h>
  50 #include <net/ethernet.h> /* for ETHERTYPE_IP */
  51 #include <net/if.h>
  52 #include <net/if_var.h>
  53 #include <net/if_clone.h>
  54 #include <net/vnet.h>
  55 #include <net/if_types.h>       /* for IFT_PFLOG */
  56 #include <net/bpf.h>            /* for BPF */
  57
  58 #include <netinet/in.h>
  59 #include <netinet/ip.h>
  60 #include <netinet/ip_icmp.h>
  61 #include <netinet/ip_var.h>
  62 #include <netinet/ip_fw.h>
  63 #include <netinet/tcp_var.h>
  64 #include <netinet/udp.h>
  65
  66 #include <netinet/ip6.h>
  67 #include <netinet/icmp6.h>
  68 #ifdef INET6
  69 #include <netinet6/in6_var.h>   /* ip6_sprintf() */
  70 #endif
  71
  72 #include <netpfil/ipfw/ip_fw_private.h>
  73
  74 #ifdef MAC
  75 #include <security/mac/mac_framework.h>
  76 #endif
  77
  78 /*
  79  * L3HDR maps an ipv4 pointer into a layer3 header pointer of type T
  80  * Other macros just cast void * into the appropriate type
  81  */
  82 #define L3HDR(T, ip)    ((T *)((u_int32_t *)(ip) + (ip)->ip_hl))
  83 #define TCP(p)          ((struct tcphdr *)(p))
  84 #define SCTP(p)         ((struct sctphdr *)(p))
  85 #define UDP(p)          ((struct udphdr *)(p))
  86 #define ICMP(p)         ((struct icmphdr *)(p))
  87 #define ICMP6(p)        ((struct icmp6_hdr *)(p))
  88
  89 #ifdef __APPLE__
  90 #undef snprintf
  91 #define snprintf        sprintf
  92 #define SNPARGS(buf, len) buf + len
  93 #define SNP(buf) buf
  94 #else   /* !__APPLE__ */
  95 #define SNPARGS(buf, len) buf + len, sizeof(buf) > len ? sizeof(buf) - len : 0
  96 #define SNP(buf) buf, sizeof(buf)
  97 #endif /* !__APPLE__ */
  98
  99 #ifdef WITHOUT_BPF
 100 void
 101 ipfw_log_bpf(int onoff)
 102 {
 103 }
 104 #else /* !WITHOUT_BPF */
 105 static VNET_DEFINE(struct ifnet *, log_if);     /* hook to attach to bpf */
 106 #define V_log_if                VNET(log_if)
 107 static struct rwlock log_if_lock;
 108 #define LOGIF_LOCK_INIT(x)      rw_init(&log_if_lock, "ipfw log_if lock")
 109 #define LOGIF_LOCK_DESTROY(x)   rw_destroy(&log_if_lock)
 110 #define LOGIF_RLOCK(x)          rw_rlock(&log_if_lock)
 111 #define LOGIF_RUNLOCK(x)        rw_runlock(&log_if_lock)
 112 #define LOGIF_WLOCK(x)          rw_wlock(&log_if_lock)
 113 #define LOGIF_WUNLOCK(x)        rw_wunlock(&log_if_lock)
 114
 115 static const char ipfwname[] = "ipfw";
 116
 117 /* we use this dummy function for all ifnet callbacks */
 118 static int
 119 log_dummy(struct ifnet *ifp, u_long cmd, caddr_t addr)
 120 {
 121         return EINVAL;
 122 }
 123
 124 static int
 125 ipfw_log_output(struct ifnet *ifp, struct mbuf *m,
 126         const struct sockaddr *dst, struct route *ro)
 127 {
 128         if (m != NULL)
 129                 FREE_PKT(m);
 130         return EINVAL;
 131 }
 132
 133 static void
 134 ipfw_log_start(struct ifnet* ifp)
 135 {
 136         panic("ipfw_log_start() must not be called");
 137 }
 138
 139 static const u_char ipfwbroadcastaddr[6] =
 140         { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
 141
 142 static int
 143 ipfw_log_clone_match(struct if_clone *ifc, const char *name)
 144 {
 145
 146         return (strncmp(name, ipfwname, sizeof(ipfwname) - 1) == 0);
 147 }
 148
 149 static int
 150 ipfw_log_clone_create(struct if_clone *ifc, char *name, size_t len,
 151     caddr_t params)
 152 {
 153         int error;
 154         int unit;
 155         struct ifnet *ifp;
 156
 157         error = ifc_name2unit(name, &unit);
 158         if (error)
 159                 return (error);
 160
 161         error = ifc_alloc_unit(ifc, &unit);
 162         if (error)
 163                 return (error);
 164
 165         ifp = if_alloc(IFT_PFLOG);
 166         if (ifp == NULL) {
 167                 ifc_free_unit(ifc, unit);
 168                 return (ENOSPC);
 169         }
 170         ifp->if_dname = ipfwname;
 171         ifp->if_dunit = unit;
 172         snprintf(ifp->if_xname, IFNAMSIZ, "%s%d", ipfwname, unit);
 173         strlcpy(name, ifp->if_xname, len);
 174         ifp->if_mtu = 65536;
 175         ifp->if_flags = IFF_UP | IFF_SIMPLEX | IFF_MULTICAST;
 176         ifp->if_init = (void *)log_dummy;
 177         ifp->if_ioctl = log_dummy;
 178         ifp->if_start = ipfw_log_start;
 179         ifp->if_output = ipfw_log_output;
 180         ifp->if_addrlen = 6;
 181         ifp->if_hdrlen = 14;
 182         ifp->if_broadcastaddr = ipfwbroadcastaddr;
 183         ifp->if_baudrate = IF_Mbps(10);
 184
 185         LOGIF_WLOCK();
 186         if (V_log_if == NULL)
 187                 V_log_if = ifp;
 188         else {
 189                 LOGIF_WUNLOCK();
 190                 if_free(ifp);
 191                 ifc_free_unit(ifc, unit);
 192                 return (EEXIST);
 193         }
 194         LOGIF_WUNLOCK();
 195         if_attach(ifp);
 196         bpfattach(ifp, DLT_EN10MB, 14);
 197
 198         return (0);
 199 }
 200
 201 static int
 202 ipfw_log_clone_destroy(struct if_clone *ifc, struct ifnet *ifp)
 203 {
 204         int unit;
 205
 206         if (ifp == NULL)
 207                 return (0);
 208
 209         LOGIF_WLOCK();
 210         if (V_log_if != NULL && ifp == V_log_if)
 211                 V_log_if = NULL;
 212         else {
 213                 LOGIF_WUNLOCK();
 214                 return (EINVAL);
 215         }
 216         LOGIF_WUNLOCK();
 217
 218         unit = ifp->if_dunit;
 219         bpfdetach(ifp);
 220         if_detach(ifp);
 221         if_free(ifp);
 222         ifc_free_unit(ifc, unit);
 223
 224         return (0);
 225 }
 226
 227 static VNET_DEFINE(struct if_clone *, ipfw_log_cloner);
 228 #define V_ipfw_log_cloner               VNET(ipfw_log_cloner)
 229
 230 void
 231 ipfw_log_bpf(int onoff)
 232 {
 233
 234         if (onoff) {
 235                 if (IS_DEFAULT_VNET(curvnet))
 236                         LOGIF_LOCK_INIT();
 237                 V_ipfw_log_cloner = if_clone_advanced(ipfwname, 0,
 238                     ipfw_log_clone_match, ipfw_log_clone_create,
 239                     ipfw_log_clone_destroy);
 240         } else {
 241                 if_clone_detach(V_ipfw_log_cloner);
 242                 if (IS_DEFAULT_VNET(curvnet))
 243                         LOGIF_LOCK_DESTROY();
 244         }
 245 }
 246 #endif /* !WITHOUT_BPF */
 247
 248 #define TARG(k, f)      IP_FW_ARG_TABLEARG(chain, k, f)
 249 /*
 250  * We enter here when we have a rule with O_LOG.
 251  * XXX this function alone takes about 2Kbytes of code!
 252  */
 253 void
 254 ipfw_log(struct ip_fw_chain *chain, struct ip_fw *f, u_int hlen,
 255     struct ip_fw_args *args, struct mbuf *m, struct ifnet *oif,
 256     u_short offset, uint32_t tablearg, struct ip *ip)
 257 {
 258         char *action;
 259         int limit_reached = 0;
 260         char action2[92], proto[128], fragment[32];
 261
 262         if (V_fw_verbose == 0) {
 263 #ifndef WITHOUT_BPF
 264                 LOGIF_RLOCK();
 265                 if (V_log_if == NULL || V_log_if->if_bpf == NULL) {
 266                         LOGIF_RUNLOCK();
 267                         return;
 268                 }
 269
 270                 if (args->eh) /* layer2, use orig hdr */
 271                         BPF_MTAP2(V_log_if, args->eh, ETHER_HDR_LEN, m);
 272                 else {
 273                         /* Add fake header. Later we will store
 274                          * more info in the header.
 275                          */
 276                         if (ip->ip_v == 4)
 277                                 BPF_MTAP2(V_log_if, "DDDDDDSSSSSS\x08\x00", ETHER_HDR_LEN, m);
 278                         else if  (ip->ip_v == 6)
 279                                 BPF_MTAP2(V_log_if, "DDDDDDSSSSSS\x86\xdd", ETHER_HDR_LEN, m);
 280                         else
 281                                 /* Obviously bogus EtherType. */
 282                                 BPF_MTAP2(V_log_if, "DDDDDDSSSSSS\xff\xff", ETHER_HDR_LEN, m);
 283                 }
 284                 LOGIF_RUNLOCK();
 285 #endif /* !WITHOUT_BPF */
 286                 return;
 287         }
 288         /* the old 'log' function */
 289         fragment[0] = '\0';
 290         proto[0] = '\0';
 291
 292         if (f == NULL) {        /* bogus pkt */
 293                 if (V_verbose_limit != 0 && V_norule_counter >= V_verbose_limit)
 294                         return;
 295                 V_norule_counter++;
 296                 if (V_norule_counter == V_verbose_limit)
 297                         limit_reached = V_verbose_limit;
 298                 action = "Refuse";
 299         } else {        /* O_LOG is the first action, find the real one */
 300                 ipfw_insn *cmd = ACTION_PTR(f);
 301                 ipfw_insn_log *l = (ipfw_insn_log *)cmd;
 302
 303                 if (l->max_log != 0 && l->log_left == 0)
 304                         return;
 305                 l->log_left--;
 306                 if (l->log_left == 0)
 307                         limit_reached = l->max_log;
 308                 cmd += F_LEN(cmd);      /* point to first action */
 309                 if (cmd->opcode == O_ALTQ) {
 310                         ipfw_insn_altq *altq = (ipfw_insn_altq *)cmd;
 311
 312                         snprintf(SNPARGS(action2, 0), "Altq %d",
 313                                 altq->qid);
 314                         cmd += F_LEN(cmd);
 315                 }
 316                 if (cmd->opcode == O_PROB || cmd->opcode == O_TAG ||
 317                     cmd->opcode == O_SETDSCP)
 318                         cmd += F_LEN(cmd);
 319
 320                 action = action2;
 321                 switch (cmd->opcode) {
 322                 case O_DENY:
 323                         action = "Deny";
 324                         break;
 325
 326                 case O_REJECT:
 327                         if (cmd->arg1==ICMP_REJECT_RST)
 328                                 action = "Reset";
 329                         else if (cmd->arg1==ICMP_UNREACH_HOST)
 330                                 action = "Reject";
 331                         else
 332                                 snprintf(SNPARGS(action2, 0), "Unreach %d",
 333                                         cmd->arg1);
 334                         break;
 335
 336                 case O_UNREACH6:
 337                         if (cmd->arg1==ICMP6_UNREACH_RST)
 338                                 action = "Reset";
 339                         else
 340                                 snprintf(SNPARGS(action2, 0), "Unreach %d",
 341                                         cmd->arg1);
 342                         break;
 343
 344                 case O_ACCEPT:
 345                         action = "Accept";
 346                         break;
 347                 case O_COUNT:
 348                         action = "Count";
 349                         break;
 350                 case O_DIVERT:
 351                         snprintf(SNPARGS(action2, 0), "Divert %d",
 352                                 TARG(cmd->arg1, divert));
 353                         break;
 354                 case O_TEE:
 355                         snprintf(SNPARGS(action2, 0), "Tee %d",
 356                                 TARG(cmd->arg1, divert));
 357                         break;
 358                 case O_SETFIB:
 359                         snprintf(SNPARGS(action2, 0), "SetFib %d",
 360                                 TARG(cmd->arg1, fib) & 0x7FFF);
 361                         break;
 362                 case O_SKIPTO:
 363                         snprintf(SNPARGS(action2, 0), "SkipTo %d",
 364                                 TARG(cmd->arg1, skipto));
 365                         break;
 366                 case O_PIPE:
 367                         snprintf(SNPARGS(action2, 0), "Pipe %d",
 368                                 TARG(cmd->arg1, pipe));
 369                         break;
 370                 case O_QUEUE:
 371                         snprintf(SNPARGS(action2, 0), "Queue %d",
 372                                 TARG(cmd->arg1, pipe));
 373                         break;
 374                 case O_FORWARD_IP: {
 375                         ipfw_insn_sa *sa = (ipfw_insn_sa *)cmd;
 376                         int len;
 377                         struct in_addr dummyaddr;
 378                         if (sa->sa.sin_addr.s_addr == INADDR_ANY)
 379                                 dummyaddr.s_addr = htonl(tablearg);
 380                         else
 381                                 dummyaddr.s_addr = sa->sa.sin_addr.s_addr;
 382
 383                         len = snprintf(SNPARGS(action2, 0), "Forward to %s",
 384                                 inet_ntoa(dummyaddr));
 385
 386                         if (sa->sa.sin_port)
 387                                 snprintf(SNPARGS(action2, len), ":%d",
 388                                     sa->sa.sin_port);
 389                         }
 390                         break;
 391 #ifdef INET6
 392                 case O_FORWARD_IP6: {
 393                         char buf[INET6_ADDRSTRLEN];
 394                         ipfw_insn_sa6 *sa = (ipfw_insn_sa6 *)cmd;
 395                         int len;
 396
 397                         len = snprintf(SNPARGS(action2, 0), "Forward to [%s]",
 398                             ip6_sprintf(buf, &sa->sa.sin6_addr));
 399
 400                         if (sa->sa.sin6_port)
 401                                 snprintf(SNPARGS(action2, len), ":%u",
 402                                     sa->sa.sin6_port);
 403                         }
 404                         break;
 405 #endif
 406                 case O_NETGRAPH:
 407                         snprintf(SNPARGS(action2, 0), "Netgraph %d",
 408                                 cmd->arg1);
 409                         break;
 410                 case O_NGTEE:
 411                         snprintf(SNPARGS(action2, 0), "Ngtee %d",
 412                                 cmd->arg1);
 413                         break;
 414                 case O_NAT:
 415                         action = "Nat";
 416                         break;
 417                 case O_REASS:
 418                         action = "Reass";
 419                         break;
 420                 case O_CALLRETURN:
 421                         if (cmd->len & F_NOT)
 422                                 action = "Return";
 423                         else
 424                                 snprintf(SNPARGS(action2, 0), "Call %d",
 425                                     cmd->arg1);
 426                         break;
 427                 default:
 428                         action = "UNKNOWN";
 429                         break;
 430                 }
 431         }
 432
 433         if (hlen == 0) {        /* non-ip */
 434                 snprintf(SNPARGS(proto, 0), "MAC");
 435
 436         } else {
 437                 int len;
 438 #ifdef INET6
 439                 char src[INET6_ADDRSTRLEN + 2], dst[INET6_ADDRSTRLEN + 2];
 440 #else
 441                 char src[INET_ADDRSTRLEN], dst[INET_ADDRSTRLEN];
 442 #endif
 443                 struct icmphdr *icmp;
 444                 struct tcphdr *tcp;
 445                 struct udphdr *udp;
 446 #ifdef INET6
 447                 struct ip6_hdr *ip6 = NULL;
 448                 struct icmp6_hdr *icmp6;
 449                 u_short ip6f_mf;
 450 #endif
 451                 src[0] = '\0';
 452                 dst[0] = '\0';
 453 #ifdef INET6
 454                 ip6f_mf = offset & IP6F_MORE_FRAG;
 455                 offset &= IP6F_OFF_MASK;
 456
 457                 if (IS_IP6_FLOW_ID(&(args->f_id))) {
 458                         char ip6buf[INET6_ADDRSTRLEN];
 459                         snprintf(src, sizeof(src), "[%s]",
 460                             ip6_sprintf(ip6buf, &args->f_id.src_ip6));
 461                         snprintf(dst, sizeof(dst), "[%s]",
 462                             ip6_sprintf(ip6buf, &args->f_id.dst_ip6));
 463
 464                         ip6 = (struct ip6_hdr *)ip;
 465                         tcp = (struct tcphdr *)(((char *)ip) + hlen);
 466                         udp = (struct udphdr *)(((char *)ip) + hlen);
 467                 } else
 468 #endif
 469                 {
 470                         tcp = L3HDR(struct tcphdr, ip);
 471                         udp = L3HDR(struct udphdr, ip);
 472
 473                         inet_ntop(AF_INET, &ip->ip_src, src, sizeof(src));
 474                         inet_ntop(AF_INET, &ip->ip_dst, dst, sizeof(dst));
 475                 }
 476
 477                 switch (args->f_id.proto) {
 478                 case IPPROTO_TCP:
 479                         len = snprintf(SNPARGS(proto, 0), "TCP %s", src);
 480                         if (offset == 0)
 481                                 snprintf(SNPARGS(proto, len), ":%d %s:%d",
 482                                     ntohs(tcp->th_sport),
 483                                     dst,
 484                                     ntohs(tcp->th_dport));
 485                         else
 486                                 snprintf(SNPARGS(proto, len), " %s", dst);
 487                         break;
 488
 489                 case IPPROTO_UDP:
 490                         len = snprintf(SNPARGS(proto, 0), "UDP %s", src);
 491                         if (offset == 0)
 492                                 snprintf(SNPARGS(proto, len), ":%d %s:%d",
 493                                     ntohs(udp->uh_sport),
 494                                     dst,
 495                                     ntohs(udp->uh_dport));
 496                         else
 497                                 snprintf(SNPARGS(proto, len), " %s", dst);
 498                         break;
 499
 500                 case IPPROTO_ICMP:
 501                         icmp = L3HDR(struct icmphdr, ip);
 502                         if (offset == 0)
 503                                 len = snprintf(SNPARGS(proto, 0),
 504                                     "ICMP:%u.%u ",
 505                                     icmp->icmp_type, icmp->icmp_code);
 506                         else
 507                                 len = snprintf(SNPARGS(proto, 0), "ICMP ");
 508                         len += snprintf(SNPARGS(proto, len), "%s", src);
 509                         snprintf(SNPARGS(proto, len), " %s", dst);
 510                         break;
 511 #ifdef INET6
 512                 case IPPROTO_ICMPV6:
 513                         icmp6 = (struct icmp6_hdr *)(((char *)ip) + hlen);
 514                         if (offset == 0)
 515                                 len = snprintf(SNPARGS(proto, 0),
 516                                     "ICMPv6:%u.%u ",
 517                                     icmp6->icmp6_type, icmp6->icmp6_code);
 518                         else
 519                                 len = snprintf(SNPARGS(proto, 0), "ICMPv6 ");
 520                         len += snprintf(SNPARGS(proto, len), "%s", src);
 521                         snprintf(SNPARGS(proto, len), " %s", dst);
 522                         break;
 523 #endif
 524                 default:
 525                         len = snprintf(SNPARGS(proto, 0), "P:%d %s",
 526                             args->f_id.proto, src);
 527                         snprintf(SNPARGS(proto, len), " %s", dst);
 528                         break;
 529                 }
 530
 531 #ifdef INET6
 532                 if (IS_IP6_FLOW_ID(&(args->f_id))) {
 533                         if (offset || ip6f_mf)
 534                                 snprintf(SNPARGS(fragment, 0),
 535                                     " (frag %08x:%d@%d%s)",
 536                                     args->f_id.extra,
 537                                     ntohs(ip6->ip6_plen) - hlen,
 538                                     ntohs(offset) << 3, ip6f_mf ? "+" : "");
 539                 } else
 540 #endif
 541                 {
 542                         int ipoff, iplen;
 543                         ipoff = ntohs(ip->ip_off);
 544                         iplen = ntohs(ip->ip_len);
 545                         if (ipoff & (IP_MF | IP_OFFMASK))
 546                                 snprintf(SNPARGS(fragment, 0),
 547                                     " (frag %d:%d@%d%s)",
 548                                     ntohs(ip->ip_id), iplen - (ip->ip_hl << 2),
 549                                     offset << 3,
 550                                     (ipoff & IP_MF) ? "+" : "");
 551                 }
 552         }
 553 #ifdef __FreeBSD__
 554         if (oif || m->m_pkthdr.rcvif)
 555                 log(LOG_SECURITY | LOG_INFO,
 556                     "ipfw: %d %s %s %s via %s%s\n",
 557                     f ? f->rulenum : -1,
 558                     action, proto, oif ? "out" : "in",
 559                     oif ? oif->if_xname : m->m_pkthdr.rcvif->if_xname,
 560                     fragment);
 561         else
 562 #endif
 563                 log(LOG_SECURITY | LOG_INFO,
 564                     "ipfw: %d %s %s [no if info]%s\n",
 565                     f ? f->rulenum : -1,
 566                     action, proto, fragment);
 567         if (limit_reached)
 568                 log(LOG_SECURITY | LOG_NOTICE,
 569                     "ipfw: limit %d reached on entry %d\n",
 570                     limit_reached, f ? f->rulenum : -1);
 571 }
 572 /* end of file */