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 */ 569