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 struct ifnet *log_if;    /* hook to attach to bpf */
 106 static struct rwlock log_if_lock;
 107 #define LOGIF_LOCK_INIT(x)      rw_init(&log_if_lock, "ipfw log_if lock")
 108 #define LOGIF_LOCK_DESTROY(x)   rw_destroy(&log_if_lock)
 109 #define LOGIF_RLOCK(x)          rw_rlock(&log_if_lock)
 110 #define LOGIF_RUNLOCK(x)        rw_runlock(&log_if_lock)
 111 #define LOGIF_WLOCK(x)          rw_wlock(&log_if_lock)
 112 #define LOGIF_WUNLOCK(x)        rw_wunlock(&log_if_lock)
 113
 114 static const char ipfwname[] = "ipfw";
 115
 116 /* we use this dummy function for all ifnet callbacks */
 117 static int
 118 log_dummy(struct ifnet *ifp, u_long cmd, caddr_t addr)
 119 {
 120         return EINVAL;
 121 }
 122
 123 static int
 124 ipfw_log_output(struct ifnet *ifp, struct mbuf *m,
 125         const struct sockaddr *dst, struct route *ro)
 126 {
 127         if (m != NULL)
 128                 FREE_PKT(m);
 129         return EINVAL;
 130 }
 131
 132 static void
 133 ipfw_log_start(struct ifnet* ifp)
 134 {
 135         panic("ipfw_log_start() must not be called");
 136 }
 137
 138 static const u_char ipfwbroadcastaddr[6] =
 139         { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
 140
 141 static int
 142 ipfw_log_clone_match(struct if_clone *ifc, const char *name)
 143 {
 144
 145         return (strncmp(name, ipfwname, sizeof(ipfwname) - 1) == 0);
 146 }
 147
 148 static int
 149 ipfw_log_clone_create(struct if_clone *ifc, char *name, size_t len,
 150     caddr_t params)
 151 {
 152         int error;
 153         int unit;
 154         struct ifnet *ifp;
 155
 156         error = ifc_name2unit(name, &unit);
 157         if (error)
 158                 return (error);
 159
 160         error = ifc_alloc_unit(ifc, &unit);
 161         if (error)
 162                 return (error);
 163
 164         ifp = if_alloc(IFT_PFLOG);
 165         if (ifp == NULL) {
 166                 ifc_free_unit(ifc, unit);
 167                 return (ENOSPC);
 168         }
 169         ifp->if_dname = ipfwname;
 170         ifp->if_dunit = unit;
 171         snprintf(ifp->if_xname, IFNAMSIZ, "%s%d", ipfwname, unit);
 172         strlcpy(name, ifp->if_xname, len);
 173         ifp->if_mtu = 65536;
 174         ifp->if_flags = IFF_UP | IFF_SIMPLEX | IFF_MULTICAST;
 175         ifp->if_init = (void *)log_dummy;
 176         ifp->if_ioctl = log_dummy;
 177         ifp->if_start = ipfw_log_start;
 178         ifp->if_output = ipfw_log_output;
 179         ifp->if_addrlen = 6;
 180         ifp->if_hdrlen = 14;
 181         ifp->if_broadcastaddr = ipfwbroadcastaddr;
 182         ifp->if_baudrate = IF_Mbps(10);
 183
 184         LOGIF_WLOCK();
 185         if (log_if == NULL)
 186                 log_if = ifp;
 187         else {
 188                 LOGIF_WUNLOCK();
 189                 if_free(ifp);
 190                 ifc_free_unit(ifc, unit);
 191                 return (EEXIST);
 192         }
 193         LOGIF_WUNLOCK();
 194         if_attach(ifp);
 195         bpfattach(ifp, DLT_EN10MB, 14);
 196
 197         return (0);
 198 }
 199
 200 static int
 201 ipfw_log_clone_destroy(struct if_clone *ifc, struct ifnet *ifp)
 202 {
 203         int unit;
 204
 205         if (ifp == NULL)
 206                 return (0);
 207
 208         LOGIF_WLOCK();
 209         if (log_if != NULL && ifp == log_if)
 210                 log_if = NULL;
 211         else {
 212                 LOGIF_WUNLOCK();
 213                 return (EINVAL);
 214         }
 215         LOGIF_WUNLOCK();
 216
 217         unit = ifp->if_dunit;
 218         bpfdetach(ifp);
 219         if_detach(ifp);
 220         if_free(ifp);
 221         ifc_free_unit(ifc, unit);
 222
 223         return (0);
 224 }
 225
 226 static struct if_clone *ipfw_log_cloner;
 227
 228 void
 229 ipfw_log_bpf(int onoff)
 230 {
 231
 232         if (onoff) {
 233                 LOGIF_LOCK_INIT();
 234                 ipfw_log_cloner = if_clone_advanced(ipfwname, 0,
 235                     ipfw_log_clone_match, ipfw_log_clone_create,
 236                     ipfw_log_clone_destroy);
 237         } else {
 238                 if_clone_detach(ipfw_log_cloner);
 239                 LOGIF_LOCK_DESTROY();
 240         }
 241 }
 242 #endif /* !WITHOUT_BPF */
 243
 244 #define TARG(k, f)      IP_FW_ARG_TABLEARG(chain, k, f)
 245 /*
 246  * We enter here when we have a rule with O_LOG.
 247  * XXX this function alone takes about 2Kbytes of code!
 248  */
 249 void
 250 ipfw_log(struct ip_fw_chain *chain, struct ip_fw *f, u_int hlen,
 251     struct ip_fw_args *args, struct mbuf *m, struct ifnet *oif,
 252     u_short offset, uint32_t tablearg, struct ip *ip)
 253 {
 254         char *action;
 255         int limit_reached = 0;
 256         char action2[92], proto[128], fragment[32];
 257
 258         if (V_fw_verbose == 0) {
 259 #ifndef WITHOUT_BPF
 260                 LOGIF_RLOCK();
 261                 if (log_if == NULL || log_if->if_bpf == NULL) {
 262                         LOGIF_RUNLOCK();
 263                         return;
 264                 }
 265
 266                 if (args->eh) /* layer2, use orig hdr */
 267                         BPF_MTAP2(log_if, args->eh, ETHER_HDR_LEN, m);
 268                 else {
 269                         /* Add fake header. Later we will store
 270                          * more info in the header.
 271                          */
 272                         if (ip->ip_v == 4)
 273                                 BPF_MTAP2(log_if, "DDDDDDSSSSSS\x08\x00", ETHER_HDR_LEN, m);
 274                         else if  (ip->ip_v == 6)
 275                                 BPF_MTAP2(log_if, "DDDDDDSSSSSS\x86\xdd", ETHER_HDR_LEN, m);
 276                         else
 277                                 /* Obviously bogus EtherType. */
 278                                 BPF_MTAP2(log_if, "DDDDDDSSSSSS\xff\xff", ETHER_HDR_LEN, m);
 279                 }
 280                 LOGIF_RUNLOCK();
 281 #endif /* !WITHOUT_BPF */
 282                 return;
 283         }
 284         /* the old 'log' function */
 285         fragment[0] = '\0';
 286         proto[0] = '\0';
 287
 288         if (f == NULL) {        /* bogus pkt */
 289                 if (V_verbose_limit != 0 && V_norule_counter >= V_verbose_limit)
 290                         return;
 291                 V_norule_counter++;
 292                 if (V_norule_counter == V_verbose_limit)
 293                         limit_reached = V_verbose_limit;
 294                 action = "Refuse";
 295         } else {        /* O_LOG is the first action, find the real one */
 296                 ipfw_insn *cmd = ACTION_PTR(f);
 297                 ipfw_insn_log *l = (ipfw_insn_log *)cmd;
 298
 299                 if (l->max_log != 0 && l->log_left == 0)
 300                         return;
 301                 l->log_left--;
 302                 if (l->log_left == 0)
 303                         limit_reached = l->max_log;
 304                 cmd += F_LEN(cmd);      /* point to first action */
 305                 if (cmd->opcode == O_ALTQ) {
 306                         ipfw_insn_altq *altq = (ipfw_insn_altq *)cmd;
 307
 308                         snprintf(SNPARGS(action2, 0), "Altq %d",
 309                                 altq->qid);
 310                         cmd += F_LEN(cmd);
 311                 }
 312                 if (cmd->opcode == O_PROB || cmd->opcode == O_TAG ||
 313                     cmd->opcode == O_SETDSCP)
 314                         cmd += F_LEN(cmd);
 315
 316                 action = action2;
 317                 switch (cmd->opcode) {
 318                 case O_DENY:
 319                         action = "Deny";
 320                         break;
 321
 322                 case O_REJECT:
 323                         if (cmd->arg1==ICMP_REJECT_RST)
 324                                 action = "Reset";
 325                         else if (cmd->arg1==ICMP_UNREACH_HOST)
 326                                 action = "Reject";
 327                         else
 328                                 snprintf(SNPARGS(action2, 0), "Unreach %d",
 329                                         cmd->arg1);
 330                         break;
 331
 332                 case O_UNREACH6:
 333                         if (cmd->arg1==ICMP6_UNREACH_RST)
 334                                 action = "Reset";
 335                         else
 336                                 snprintf(SNPARGS(action2, 0), "Unreach %d",
 337                                         cmd->arg1);
 338                         break;
 339
 340                 case O_ACCEPT:
 341                         action = "Accept";
 342                         break;
 343                 case O_COUNT:
 344                         action = "Count";
 345                         break;
 346                 case O_DIVERT:
 347                         snprintf(SNPARGS(action2, 0), "Divert %d",
 348                                 TARG(cmd->arg1, divert));
 349                         break;
 350                 case O_TEE:
 351                         snprintf(SNPARGS(action2, 0), "Tee %d",
 352                                 TARG(cmd->arg1, divert));
 353                         break;
 354                 case O_SETFIB:
 355                         snprintf(SNPARGS(action2, 0), "SetFib %d",
 356                                 TARG(cmd->arg1, fib) & 0x7FFF);
 357                         break;
 358                 case O_SKIPTO:
 359                         snprintf(SNPARGS(action2, 0), "SkipTo %d",
 360                                 TARG(cmd->arg1, skipto));
 361                         break;
 362                 case O_PIPE:
 363                         snprintf(SNPARGS(action2, 0), "Pipe %d",
 364                                 TARG(cmd->arg1, pipe));
 365                         break;
 366                 case O_QUEUE:
 367                         snprintf(SNPARGS(action2, 0), "Queue %d",
 368                                 TARG(cmd->arg1, pipe));
 369                         break;
 370                 case O_FORWARD_IP: {
 371                         ipfw_insn_sa *sa = (ipfw_insn_sa *)cmd;
 372                         int len;
 373                         struct in_addr dummyaddr;
 374                         if (sa->sa.sin_addr.s_addr == INADDR_ANY)
 375                                 dummyaddr.s_addr = htonl(tablearg);
 376                         else
 377                                 dummyaddr.s_addr = sa->sa.sin_addr.s_addr;
 378
 379                         len = snprintf(SNPARGS(action2, 0), "Forward to %s",
 380                                 inet_ntoa(dummyaddr));
 381
 382                         if (sa->sa.sin_port)
 383                                 snprintf(SNPARGS(action2, len), ":%d",
 384                                     sa->sa.sin_port);
 385                         }
 386                         break;
 387 #ifdef INET6
 388                 case O_FORWARD_IP6: {
 389                         char buf[INET6_ADDRSTRLEN];
 390                         ipfw_insn_sa6 *sa = (ipfw_insn_sa6 *)cmd;
 391                         int len;
 392
 393                         len = snprintf(SNPARGS(action2, 0), "Forward to [%s]",
 394                             ip6_sprintf(buf, &sa->sa.sin6_addr));
 395
 396                         if (sa->sa.sin6_port)
 397                                 snprintf(SNPARGS(action2, len), ":%u",
 398                                     sa->sa.sin6_port);
 399                         }
 400                         break;
 401 #endif
 402                 case O_NETGRAPH:
 403                         snprintf(SNPARGS(action2, 0), "Netgraph %d",
 404                                 cmd->arg1);
 405                         break;
 406                 case O_NGTEE:
 407                         snprintf(SNPARGS(action2, 0), "Ngtee %d",
 408                                 cmd->arg1);
 409                         break;
 410                 case O_NAT:
 411                         action = "Nat";
 412                         break;
 413                 case O_REASS:
 414                         action = "Reass";
 415                         break;
 416                 case O_CALLRETURN:
 417                         if (cmd->len & F_NOT)
 418                                 action = "Return";
 419                         else
 420                                 snprintf(SNPARGS(action2, 0), "Call %d",
 421                                     cmd->arg1);
 422                         break;
 423                 default:
 424                         action = "UNKNOWN";
 425                         break;
 426                 }
 427         }
 428
 429         if (hlen == 0) {        /* non-ip */
 430                 snprintf(SNPARGS(proto, 0), "MAC");
 431
 432         } else {
 433                 int len;
 434 #ifdef INET6
 435                 char src[INET6_ADDRSTRLEN + 2], dst[INET6_ADDRSTRLEN + 2];
 436 #else
 437                 char src[INET_ADDRSTRLEN], dst[INET_ADDRSTRLEN];
 438 #endif
 439                 struct icmphdr *icmp;
 440                 struct tcphdr *tcp;
 441                 struct udphdr *udp;
 442 #ifdef INET6
 443                 struct ip6_hdr *ip6 = NULL;
 444                 struct icmp6_hdr *icmp6;
 445                 u_short ip6f_mf;
 446 #endif
 447                 src[0] = '\0';
 448                 dst[0] = '\0';
 449 #ifdef INET6
 450                 ip6f_mf = offset & IP6F_MORE_FRAG;
 451                 offset &= IP6F_OFF_MASK;
 452
 453                 if (IS_IP6_FLOW_ID(&(args->f_id))) {
 454                         char ip6buf[INET6_ADDRSTRLEN];
 455                         snprintf(src, sizeof(src), "[%s]",
 456                             ip6_sprintf(ip6buf, &args->f_id.src_ip6));
 457                         snprintf(dst, sizeof(dst), "[%s]",
 458                             ip6_sprintf(ip6buf, &args->f_id.dst_ip6));
 459
 460                         ip6 = (struct ip6_hdr *)ip;
 461                         tcp = (struct tcphdr *)(((char *)ip) + hlen);
 462                         udp = (struct udphdr *)(((char *)ip) + hlen);
 463                 } else
 464 #endif
 465                 {
 466                         tcp = L3HDR(struct tcphdr, ip);
 467                         udp = L3HDR(struct udphdr, ip);
 468
 469                         inet_ntop(AF_INET, &ip->ip_src, src, sizeof(src));
 470                         inet_ntop(AF_INET, &ip->ip_dst, dst, sizeof(dst));
 471                 }
 472
 473                 switch (args->f_id.proto) {
 474                 case IPPROTO_TCP:
 475                         len = snprintf(SNPARGS(proto, 0), "TCP %s", src);
 476                         if (offset == 0)
 477                                 snprintf(SNPARGS(proto, len), ":%d %s:%d",
 478                                     ntohs(tcp->th_sport),
 479                                     dst,
 480                                     ntohs(tcp->th_dport));
 481                         else
 482                                 snprintf(SNPARGS(proto, len), " %s", dst);
 483                         break;
 484
 485                 case IPPROTO_UDP:
 486                         len = snprintf(SNPARGS(proto, 0), "UDP %s", src);
 487                         if (offset == 0)
 488                                 snprintf(SNPARGS(proto, len), ":%d %s:%d",
 489                                     ntohs(udp->uh_sport),
 490                                     dst,
 491                                     ntohs(udp->uh_dport));
 492                         else
 493                                 snprintf(SNPARGS(proto, len), " %s", dst);
 494                         break;
 495
 496                 case IPPROTO_ICMP:
 497                         icmp = L3HDR(struct icmphdr, ip);
 498                         if (offset == 0)
 499                                 len = snprintf(SNPARGS(proto, 0),
 500                                     "ICMP:%u.%u ",
 501                                     icmp->icmp_type, icmp->icmp_code);
 502                         else
 503                                 len = snprintf(SNPARGS(proto, 0), "ICMP ");
 504                         len += snprintf(SNPARGS(proto, len), "%s", src);
 505                         snprintf(SNPARGS(proto, len), " %s", dst);
 506                         break;
 507 #ifdef INET6
 508                 case IPPROTO_ICMPV6:
 509                         icmp6 = (struct icmp6_hdr *)(((char *)ip) + hlen);
 510                         if (offset == 0)
 511                                 len = snprintf(SNPARGS(proto, 0),
 512                                     "ICMPv6:%u.%u ",
 513                                     icmp6->icmp6_type, icmp6->icmp6_code);
 514                         else
 515                                 len = snprintf(SNPARGS(proto, 0), "ICMPv6 ");
 516                         len += snprintf(SNPARGS(proto, len), "%s", src);
 517                         snprintf(SNPARGS(proto, len), " %s", dst);
 518                         break;
 519 #endif
 520                 default:
 521                         len = snprintf(SNPARGS(proto, 0), "P:%d %s",
 522                             args->f_id.proto, src);
 523                         snprintf(SNPARGS(proto, len), " %s", dst);
 524                         break;
 525                 }
 526
 527 #ifdef INET6
 528                 if (IS_IP6_FLOW_ID(&(args->f_id))) {
 529                         if (offset || ip6f_mf)
 530                                 snprintf(SNPARGS(fragment, 0),
 531                                     " (frag %08x:%d@%d%s)",
 532                                     args->f_id.extra,
 533                                     ntohs(ip6->ip6_plen) - hlen,
 534                                     ntohs(offset) << 3, ip6f_mf ? "+" : "");
 535                 } else
 536 #endif
 537                 {
 538                         int ipoff, iplen;
 539                         ipoff = ntohs(ip->ip_off);
 540                         iplen = ntohs(ip->ip_len);
 541                         if (ipoff & (IP_MF | IP_OFFMASK))
 542                                 snprintf(SNPARGS(fragment, 0),
 543                                     " (frag %d:%d@%d%s)",
 544                                     ntohs(ip->ip_id), iplen - (ip->ip_hl << 2),
 545                                     offset << 3,
 546                                     (ipoff & IP_MF) ? "+" : "");
 547                 }
 548         }
 549 #ifdef __FreeBSD__
 550         if (oif || m->m_pkthdr.rcvif)
 551                 log(LOG_SECURITY | LOG_INFO,
 552                     "ipfw: %d %s %s %s via %s%s\n",
 553                     f ? f->rulenum : -1,
 554                     action, proto, oif ? "out" : "in",
 555                     oif ? oif->if_xname : m->m_pkthdr.rcvif->if_xname,
 556                     fragment);
 557         else
 558 #endif
 559                 log(LOG_SECURITY | LOG_INFO,
 560                     "ipfw: %d %s %s [no if info]%s\n",
 561                     f ? f->rulenum : -1,
 562                     action, proto, fragment);
 563         if (limit_reached)
 564                 log(LOG_SECURITY | LOG_NOTICE,
 565                     "ipfw: limit %d reached on entry %d\n",
 566                     limit_reached, f ? f->rulenum : -1);
 567 }
 568 /* end of file */