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 */ 573