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