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