1 /*- 2 * Copyright (c) 2002-2003 Luigi Rizzo 3 * Copyright (c) 1996 Alex Nash, Paul Traina, Poul-Henning Kamp 4 * Copyright (c) 1994 Ugen J.S.Antsilevich 5 * 6 * Idea and grammar partially left from: 7 * Copyright (c) 1993 Daniel Boulet 8 * 9 * Redistribution and use in source forms, with and without modification, 10 * are permitted provided that this entire comment appears intact. 11 * 12 * Redistribution in binary form may occur without any restrictions. 13 * Obviously, it would be nice if you gave credit where credit is due 14 * but requiring it would be too onerous. 15 * 16 * This software is provided ``AS IS'' without any warranties of any kind. 17 * 18 * NEW command line interface for IP firewall facility 19 * 20 * $FreeBSD$ 21 * 22 * ipv6 support 23 */ 24 25 #include <sys/types.h> 26 #include <sys/socket.h> 27 28 #include "ipfw2.h" 29 30 #include <err.h> 31 #include <netdb.h> 32 #include <stdio.h> 33 #include <stdlib.h> 34 #include <string.h> 35 #include <sysexits.h> 36 37 #include <net/if.h> 38 #include <netinet/in.h> 39 #include <netinet/in_systm.h> 40 #include <netinet/ip.h> 41 #include <netinet/icmp6.h> 42 #include <netinet/ip_fw.h> 43 #include <arpa/inet.h> 44 45 #define CHECK_LENGTH(v, len) do { \ 46 if ((v) < (len)) \ 47 errx(EX_DATAERR, "Rule too long"); \ 48 } while (0) 49 50 static struct _s_x icmp6codes[] = { 51 { "no-route", ICMP6_DST_UNREACH_NOROUTE }, 52 { "admin-prohib", ICMP6_DST_UNREACH_ADMIN }, 53 { "address", ICMP6_DST_UNREACH_ADDR }, 54 { "port", ICMP6_DST_UNREACH_NOPORT }, 55 { NULL, 0 } 56 }; 57 58 void 59 fill_unreach6_code(u_short *codep, char *str) 60 { 61 int val; 62 char *s; 63 64 val = strtoul(str, &s, 0); 65 if (s == str || *s != '\0' || val >= 0x100) 66 val = match_token(icmp6codes, str); 67 if (val < 0) 68 errx(EX_DATAERR, "unknown ICMPv6 unreachable code ``%s''", str); 69 *codep = val; 70 return; 71 } 72 73 void 74 print_unreach6_code(struct buf_pr *bp, uint16_t code) 75 { 76 char const *s = match_value(icmp6codes, code); 77 78 if (s != NULL) 79 bprintf(bp, "unreach6 %s", s); 80 else 81 bprintf(bp, "unreach6 %u", code); 82 } 83 84 /* 85 * Print the ip address contained in a command. 86 */ 87 void 88 print_ip6(struct buf_pr *bp, ipfw_insn_ip6 *cmd) 89 { 90 char trad[255]; 91 struct hostent *he = NULL; 92 struct in6_addr *a = &(cmd->addr6); 93 int len, mb; 94 95 len = F_LEN((ipfw_insn *) cmd) - 1; 96 if (cmd->o.opcode == O_IP6_SRC_ME || cmd->o.opcode == O_IP6_DST_ME) { 97 bprintf(bp, " me6"); 98 return; 99 } 100 if (cmd->o.opcode == O_IP6) { 101 bprintf(bp, " ip6"); 102 return; 103 } 104 105 /* 106 * len == 4 indicates a single IP, whereas lists of 1 or more 107 * addr/mask pairs have len = (2n+1). We convert len to n so we 108 * use that to count the number of entries. 109 */ 110 bprintf(bp, " "); 111 for (len = len / 4; len > 0; len -= 2, a += 2) { 112 /* mask length */ 113 mb = (cmd->o.opcode == O_IP6_SRC || 114 cmd->o.opcode == O_IP6_DST) ? 128: 115 contigmask((uint8_t *)&(a[1]), 128); 116 117 if (mb == 128 && co.do_resolv) 118 he = gethostbyaddr((char *)a, sizeof(*a), AF_INET6); 119 120 if (he != NULL) /* resolved to name */ 121 bprintf(bp, "%s", he->h_name); 122 else if (mb == 0) /* any */ 123 bprintf(bp, "any"); 124 else { /* numeric IP followed by some kind of mask */ 125 if (inet_ntop(AF_INET6, a, trad, 126 sizeof(trad)) == NULL) 127 bprintf(bp, "Error ntop in print_ip6\n"); 128 bprintf(bp, "%s", trad ); 129 if (mb < 0) /* mask not contiguous */ 130 bprintf(bp, "/%s", inet_ntop(AF_INET6, &a[1], 131 trad, sizeof(trad))); 132 else if (mb < 128) 133 bprintf(bp, "/%d", mb); 134 } 135 if (len > 2) 136 bprintf(bp, ","); 137 } 138 } 139 140 void 141 fill_icmp6types(ipfw_insn_icmp6 *cmd, char *av, int cblen) 142 { 143 uint8_t type; 144 145 CHECK_LENGTH(cblen, F_INSN_SIZE(ipfw_insn_icmp6)); 146 memset(cmd, 0, sizeof(*cmd)); 147 while (*av) { 148 if (*av == ',') 149 av++; 150 type = strtoul(av, &av, 0); 151 if (*av != ',' && *av != '\0') 152 errx(EX_DATAERR, "invalid ICMP6 type"); 153 /* 154 * XXX: shouldn't this be 0xFF? I can't see any reason why 155 * we shouldn't be able to filter all possiable values 156 * regardless of the ability of the rest of the kernel to do 157 * anything useful with them. 158 */ 159 if (type > ICMP6_MAXTYPE) 160 errx(EX_DATAERR, "ICMP6 type out of range"); 161 cmd->d[type / 32] |= ( 1 << (type % 32)); 162 } 163 cmd->o.opcode = O_ICMP6TYPE; 164 cmd->o.len |= F_INSN_SIZE(ipfw_insn_icmp6); 165 } 166 167 void 168 print_icmp6types(struct buf_pr *bp, ipfw_insn_u32 *cmd) 169 { 170 int i, j; 171 char sep= ' '; 172 173 bprintf(bp, " icmp6types"); 174 for (i = 0; i < 7; i++) 175 for (j=0; j < 32; ++j) { 176 if ( (cmd->d[i] & (1 << (j))) == 0) 177 continue; 178 bprintf(bp, "%c%d", sep, (i*32 + j)); 179 sep = ','; 180 } 181 } 182 183 void 184 print_flow6id(struct buf_pr *bp, ipfw_insn_u32 *cmd) 185 { 186 uint16_t i, limit = cmd->o.arg1; 187 char sep = ','; 188 189 bprintf(bp, " flow-id "); 190 for( i=0; i < limit; ++i) { 191 if (i == limit - 1) 192 sep = ' '; 193 bprintf(bp, "%d%c", cmd->d[i], sep); 194 } 195 } 196 197 /* structure and define for the extension header in ipv6 */ 198 static struct _s_x ext6hdrcodes[] = { 199 { "frag", EXT_FRAGMENT }, 200 { "hopopt", EXT_HOPOPTS }, 201 { "route", EXT_ROUTING }, 202 { "dstopt", EXT_DSTOPTS }, 203 { "ah", EXT_AH }, 204 { "esp", EXT_ESP }, 205 { "rthdr0", EXT_RTHDR0 }, 206 { "rthdr2", EXT_RTHDR2 }, 207 { NULL, 0 } 208 }; 209 210 /* fills command for the extension header filtering */ 211 int 212 fill_ext6hdr( ipfw_insn *cmd, char *av) 213 { 214 int tok; 215 char *s = av; 216 217 cmd->arg1 = 0; 218 while(s) { 219 av = strsep( &s, ",") ; 220 tok = match_token(ext6hdrcodes, av); 221 switch (tok) { 222 case EXT_FRAGMENT: 223 cmd->arg1 |= EXT_FRAGMENT; 224 break; 225 case EXT_HOPOPTS: 226 cmd->arg1 |= EXT_HOPOPTS; 227 break; 228 case EXT_ROUTING: 229 cmd->arg1 |= EXT_ROUTING; 230 break; 231 case EXT_DSTOPTS: 232 cmd->arg1 |= EXT_DSTOPTS; 233 break; 234 case EXT_AH: 235 cmd->arg1 |= EXT_AH; 236 break; 237 case EXT_ESP: 238 cmd->arg1 |= EXT_ESP; 239 break; 240 case EXT_RTHDR0: 241 cmd->arg1 |= EXT_RTHDR0; 242 break; 243 case EXT_RTHDR2: 244 cmd->arg1 |= EXT_RTHDR2; 245 break; 246 default: 247 errx(EX_DATAERR, 248 "invalid option for ipv6 exten header"); 249 break; 250 } 251 } 252 if (cmd->arg1 == 0) 253 return (0); 254 cmd->opcode = O_EXT_HDR; 255 cmd->len |= F_INSN_SIZE(ipfw_insn); 256 return (1); 257 } 258 259 void 260 print_ext6hdr(struct buf_pr *bp, ipfw_insn *cmd ) 261 { 262 char sep = ' '; 263 264 bprintf(bp, " extension header:"); 265 if (cmd->arg1 & EXT_FRAGMENT) { 266 bprintf(bp, "%cfragmentation", sep); 267 sep = ','; 268 } 269 if (cmd->arg1 & EXT_HOPOPTS) { 270 bprintf(bp, "%chop options", sep); 271 sep = ','; 272 } 273 if (cmd->arg1 & EXT_ROUTING) { 274 bprintf(bp, "%crouting options", sep); 275 sep = ','; 276 } 277 if (cmd->arg1 & EXT_RTHDR0) { 278 bprintf(bp, "%crthdr0", sep); 279 sep = ','; 280 } 281 if (cmd->arg1 & EXT_RTHDR2) { 282 bprintf(bp, "%crthdr2", sep); 283 sep = ','; 284 } 285 if (cmd->arg1 & EXT_DSTOPTS) { 286 bprintf(bp, "%cdestination options", sep); 287 sep = ','; 288 } 289 if (cmd->arg1 & EXT_AH) { 290 bprintf(bp, "%cauthentication header", sep); 291 sep = ','; 292 } 293 if (cmd->arg1 & EXT_ESP) { 294 bprintf(bp, "%cencapsulated security payload", sep); 295 } 296 } 297 298 /* Try to find ipv6 address by hostname */ 299 static int 300 lookup_host6 (char *host, struct in6_addr *ip6addr) 301 { 302 struct hostent *he; 303 304 if (!inet_pton(AF_INET6, host, ip6addr)) { 305 if ((he = gethostbyname2(host, AF_INET6)) == NULL) 306 return(-1); 307 memcpy(ip6addr, he->h_addr_list[0], sizeof( struct in6_addr)); 308 } 309 return (0); 310 } 311 312 313 /* 314 * fill the addr and mask fields in the instruction as appropriate from av. 315 * Update length as appropriate. 316 * The following formats are allowed: 317 * any matches any IP6. Actually returns an empty instruction. 318 * me returns O_IP6_*_ME 319 * 320 * 03f1::234:123:0342 single IP6 address 321 * 03f1::234:123:0342/24 address/masklen 322 * 03f1::234:123:0342/ffff::ffff:ffff address/mask 323 * 03f1::234:123:0342/24,03f1::234:123:0343/ List of address 324 * 325 * Set of address (as in ipv6) not supported because ipv6 address 326 * are typically random past the initial prefix. 327 * Return 1 on success, 0 on failure. 328 */ 329 static int 330 fill_ip6(ipfw_insn_ip6 *cmd, char *av, int cblen, struct tidx *tstate) 331 { 332 int len = 0; 333 struct in6_addr *d = &(cmd->addr6); 334 char *oav; 335 /* 336 * Needed for multiple address. 337 * Note d[1] points to struct in6_add r mask6 of cmd 338 */ 339 340 cmd->o.len &= ~F_LEN_MASK; /* zero len */ 341 342 if (strcmp(av, "any") == 0) 343 return (1); 344 345 346 if (strcmp(av, "me") == 0) { /* Set the data for "me" opt*/ 347 cmd->o.len |= F_INSN_SIZE(ipfw_insn); 348 return (1); 349 } 350 351 if (strcmp(av, "me6") == 0) { /* Set the data for "me" opt*/ 352 cmd->o.len |= F_INSN_SIZE(ipfw_insn); 353 return (1); 354 } 355 356 if (strncmp(av, "table(", 6) == 0) { 357 fill_table(&cmd->o, av, O_IP_DST_LOOKUP, tstate); 358 return (1); 359 } 360 361 oav = av = strdup(av); 362 while (av) { 363 /* 364 * After the address we can have '/' indicating a mask, 365 * or ',' indicating another address follows. 366 */ 367 368 char *p, *q; 369 int masklen; 370 char md = '\0'; 371 372 CHECK_LENGTH(cblen, 1 + len + 2 * F_INSN_SIZE(struct in6_addr)); 373 374 if ((q = strchr(av, ',')) ) { 375 *q = '\0'; 376 q++; 377 } 378 379 if ((p = strchr(av, '/')) ) { 380 md = *p; /* save the separator */ 381 *p = '\0'; /* terminate address string */ 382 p++; /* and skip past it */ 383 } 384 /* now p points to NULL, mask or next entry */ 385 386 /* lookup stores address in *d as a side effect */ 387 if (lookup_host6(av, d) != 0) { 388 /* XXX: failed. Free memory and go */ 389 errx(EX_DATAERR, "bad address \"%s\"", av); 390 } 391 /* next, look at the mask, if any */ 392 if (md == '/' && strchr(p, ':')) { 393 if (!inet_pton(AF_INET6, p, &d[1])) 394 errx(EX_DATAERR, "bad mask \"%s\"", p); 395 396 masklen = contigmask((uint8_t *)&(d[1]), 128); 397 } else { 398 masklen = (md == '/') ? atoi(p) : 128; 399 if (masklen > 128 || masklen < 0) 400 errx(EX_DATAERR, "bad width \"%s\''", p); 401 else 402 n2mask(&d[1], masklen); 403 } 404 405 APPLY_MASK(d, &d[1]); /* mask base address with mask */ 406 407 av = q; 408 409 /* Check this entry */ 410 if (masklen == 0) { 411 /* 412 * 'any' turns the entire list into a NOP. 413 * 'not any' never matches, so it is removed from the 414 * list unless it is the only item, in which case we 415 * report an error. 416 */ 417 if (cmd->o.len & F_NOT && av == NULL && len == 0) 418 errx(EX_DATAERR, "not any never matches"); 419 continue; 420 } 421 422 /* 423 * A single IP can be stored alone 424 */ 425 if (masklen == 128 && av == NULL && len == 0) { 426 len = F_INSN_SIZE(struct in6_addr); 427 break; 428 } 429 430 /* Update length and pointer to arguments */ 431 len += F_INSN_SIZE(struct in6_addr)*2; 432 d += 2; 433 } /* end while */ 434 435 /* 436 * Total length of the command, remember that 1 is the size of 437 * the base command. 438 */ 439 if (len + 1 > F_LEN_MASK) 440 errx(EX_DATAERR, "address list too long"); 441 cmd->o.len |= len+1; 442 free(oav); 443 return (1); 444 } 445 446 /* 447 * fills command for ipv6 flow-id filtering 448 * note that the 20 bit flow number is stored in a array of u_int32_t 449 * it's supported lists of flow-id, so in the o.arg1 we store how many 450 * additional flow-id we want to filter, the basic is 1 451 */ 452 void 453 fill_flow6( ipfw_insn_u32 *cmd, char *av, int cblen) 454 { 455 u_int32_t type; /* Current flow number */ 456 u_int16_t nflow = 0; /* Current flow index */ 457 char *s = av; 458 cmd->d[0] = 0; /* Initializing the base number*/ 459 460 while (s) { 461 CHECK_LENGTH(cblen, F_INSN_SIZE(ipfw_insn_u32) + nflow + 1); 462 463 av = strsep( &s, ",") ; 464 type = strtoul(av, &av, 0); 465 if (*av != ',' && *av != '\0') 466 errx(EX_DATAERR, "invalid ipv6 flow number %s", av); 467 if (type > 0xfffff) 468 errx(EX_DATAERR, "flow number out of range %s", av); 469 cmd->d[nflow] |= type; 470 nflow++; 471 } 472 if( nflow > 0 ) { 473 cmd->o.opcode = O_FLOW6ID; 474 cmd->o.len |= F_INSN_SIZE(ipfw_insn_u32) + nflow; 475 cmd->o.arg1 = nflow; 476 } 477 else { 478 errx(EX_DATAERR, "invalid ipv6 flow number %s", av); 479 } 480 } 481 482 ipfw_insn * 483 add_srcip6(ipfw_insn *cmd, char *av, int cblen, struct tidx *tstate) 484 { 485 486 fill_ip6((ipfw_insn_ip6 *)cmd, av, cblen, tstate); 487 if (cmd->opcode == O_IP_DST_SET) /* set */ 488 cmd->opcode = O_IP_SRC_SET; 489 else if (cmd->opcode == O_IP_DST_LOOKUP) /* table */ 490 cmd->opcode = O_IP_SRC_LOOKUP; 491 else if (F_LEN(cmd) == 0) { /* any */ 492 } else if (F_LEN(cmd) == F_INSN_SIZE(ipfw_insn)) { /* "me" */ 493 cmd->opcode = O_IP6_SRC_ME; 494 } else if (F_LEN(cmd) == 495 (F_INSN_SIZE(struct in6_addr) + F_INSN_SIZE(ipfw_insn))) { 496 /* single IP, no mask*/ 497 cmd->opcode = O_IP6_SRC; 498 } else { /* addr/mask opt */ 499 cmd->opcode = O_IP6_SRC_MASK; 500 } 501 return cmd; 502 } 503 504 ipfw_insn * 505 add_dstip6(ipfw_insn *cmd, char *av, int cblen, struct tidx *tstate) 506 { 507 508 fill_ip6((ipfw_insn_ip6 *)cmd, av, cblen, tstate); 509 if (cmd->opcode == O_IP_DST_SET) /* set */ 510 ; 511 else if (cmd->opcode == O_IP_DST_LOOKUP) /* table */ 512 ; 513 else if (F_LEN(cmd) == 0) { /* any */ 514 } else if (F_LEN(cmd) == F_INSN_SIZE(ipfw_insn)) { /* "me" */ 515 cmd->opcode = O_IP6_DST_ME; 516 } else if (F_LEN(cmd) == 517 (F_INSN_SIZE(struct in6_addr) + F_INSN_SIZE(ipfw_insn))) { 518 /* single IP, no mask*/ 519 cmd->opcode = O_IP6_DST; 520 } else { /* addr/mask opt */ 521 cmd->opcode = O_IP6_DST_MASK; 522 } 523 return cmd; 524 } 525