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, const ipfw_insn_ip6 *cmd) 89 { 90 char trad[255]; 91 struct hostent *he = NULL; 92 const struct in6_addr *a = &(cmd->addr6); 93 int len, mb; 94 95 len = F_LEN((const 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((const uint8_t *)&(a[1]), 128); 116 117 if (mb == 128 && g_co.do_resolv) 118 he = gethostbyaddr((const char *)a, sizeof(*a), 119 AF_INET6); 120 121 if (he != NULL) /* resolved to name */ 122 bprintf(bp, "%s", he->h_name); 123 else if (mb == 0) /* any */ 124 bprintf(bp, "any"); 125 else { /* numeric IP followed by some kind of mask */ 126 if (inet_ntop(AF_INET6, a, trad, 127 sizeof(trad)) == NULL) 128 bprintf(bp, "Error ntop in print_ip6\n"); 129 bprintf(bp, "%s", trad ); 130 if (mb < 0) /* mask not contiguous */ 131 bprintf(bp, "/%s", inet_ntop(AF_INET6, &a[1], 132 trad, sizeof(trad))); 133 else if (mb < 128) 134 bprintf(bp, "/%d", mb); 135 } 136 if (len > 2) 137 bprintf(bp, ","); 138 } 139 } 140 141 void 142 fill_icmp6types(ipfw_insn_icmp6 *cmd, char *av, int cblen) 143 { 144 uint8_t type; 145 146 CHECK_LENGTH(cblen, (int)F_INSN_SIZE(ipfw_insn_icmp6)); 147 memset(cmd, 0, sizeof(*cmd)); 148 while (*av) { 149 if (*av == ',') 150 av++; 151 type = strtoul(av, &av, 0); 152 if (*av != ',' && *av != '\0') 153 errx(EX_DATAERR, "invalid ICMP6 type"); 154 /* 155 * XXX: shouldn't this be 0xFF? I can't see any reason why 156 * we shouldn't be able to filter all possiable values 157 * regardless of the ability of the rest of the kernel to do 158 * anything useful with them. 159 */ 160 if (type > ICMP6_MAXTYPE) 161 errx(EX_DATAERR, "ICMP6 type out of range"); 162 cmd->d[type / 32] |= ( 1 << (type % 32)); 163 } 164 cmd->o.opcode = O_ICMP6TYPE; 165 cmd->o.len |= F_INSN_SIZE(ipfw_insn_icmp6); 166 } 167 168 void 169 print_icmp6types(struct buf_pr *bp, const ipfw_insn_u32 *cmd) 170 { 171 int i, j; 172 char sep= ' '; 173 174 bprintf(bp, " icmp6types"); 175 for (i = 0; i < 7; i++) 176 for (j=0; j < 32; ++j) { 177 if ( (cmd->d[i] & (1 << (j))) == 0) 178 continue; 179 bprintf(bp, "%c%d", sep, (i*32 + j)); 180 sep = ','; 181 } 182 } 183 184 void 185 print_flow6id(struct buf_pr *bp, const ipfw_insn_u32 *cmd) 186 { 187 uint16_t i, limit = cmd->o.arg1; 188 char sep = ','; 189 190 bprintf(bp, " flow-id "); 191 for( i=0; i < limit; ++i) { 192 if (i == limit - 1) 193 sep = ' '; 194 bprintf(bp, "%d%c", cmd->d[i], sep); 195 } 196 } 197 198 /* structure and define for the extension header in ipv6 */ 199 static struct _s_x ext6hdrcodes[] = { 200 { "frag", EXT_FRAGMENT }, 201 { "hopopt", EXT_HOPOPTS }, 202 { "route", EXT_ROUTING }, 203 { "dstopt", EXT_DSTOPTS }, 204 { "ah", EXT_AH }, 205 { "esp", EXT_ESP }, 206 { "rthdr0", EXT_RTHDR0 }, 207 { "rthdr2", EXT_RTHDR2 }, 208 { NULL, 0 } 209 }; 210 211 /* fills command for the extension header filtering */ 212 int 213 fill_ext6hdr( ipfw_insn *cmd, char *av) 214 { 215 int tok; 216 char *s = av; 217 218 cmd->arg1 = 0; 219 while(s) { 220 av = strsep( &s, ",") ; 221 tok = match_token(ext6hdrcodes, av); 222 switch (tok) { 223 case EXT_FRAGMENT: 224 cmd->arg1 |= EXT_FRAGMENT; 225 break; 226 case EXT_HOPOPTS: 227 cmd->arg1 |= EXT_HOPOPTS; 228 break; 229 case EXT_ROUTING: 230 cmd->arg1 |= EXT_ROUTING; 231 break; 232 case EXT_DSTOPTS: 233 cmd->arg1 |= EXT_DSTOPTS; 234 break; 235 case EXT_AH: 236 cmd->arg1 |= EXT_AH; 237 break; 238 case EXT_ESP: 239 cmd->arg1 |= EXT_ESP; 240 break; 241 case EXT_RTHDR0: 242 cmd->arg1 |= EXT_RTHDR0; 243 break; 244 case EXT_RTHDR2: 245 cmd->arg1 |= EXT_RTHDR2; 246 break; 247 default: 248 errx(EX_DATAERR, 249 "invalid option for ipv6 exten header"); 250 break; 251 } 252 } 253 if (cmd->arg1 == 0) 254 return (0); 255 cmd->opcode = O_EXT_HDR; 256 cmd->len |= F_INSN_SIZE(ipfw_insn); 257 return (1); 258 } 259 260 void 261 print_ext6hdr(struct buf_pr *bp, const ipfw_insn *cmd ) 262 { 263 char sep = ' '; 264 265 bprintf(bp, " extension header:"); 266 if (cmd->arg1 & EXT_FRAGMENT) { 267 bprintf(bp, "%cfragmentation", sep); 268 sep = ','; 269 } 270 if (cmd->arg1 & EXT_HOPOPTS) { 271 bprintf(bp, "%chop options", sep); 272 sep = ','; 273 } 274 if (cmd->arg1 & EXT_ROUTING) { 275 bprintf(bp, "%crouting options", sep); 276 sep = ','; 277 } 278 if (cmd->arg1 & EXT_RTHDR0) { 279 bprintf(bp, "%crthdr0", sep); 280 sep = ','; 281 } 282 if (cmd->arg1 & EXT_RTHDR2) { 283 bprintf(bp, "%crthdr2", sep); 284 sep = ','; 285 } 286 if (cmd->arg1 & EXT_DSTOPTS) { 287 bprintf(bp, "%cdestination options", sep); 288 sep = ','; 289 } 290 if (cmd->arg1 & EXT_AH) { 291 bprintf(bp, "%cauthentication header", sep); 292 sep = ','; 293 } 294 if (cmd->arg1 & EXT_ESP) { 295 bprintf(bp, "%cencapsulated security payload", sep); 296 } 297 } 298 299 /* Try to find ipv6 address by hostname */ 300 static int 301 lookup_host6 (char *host, struct in6_addr *ip6addr) 302 { 303 struct hostent *he; 304 305 if (!inet_pton(AF_INET6, host, ip6addr)) { 306 if ((he = gethostbyname2(host, AF_INET6)) == NULL) 307 return(-1); 308 memcpy(ip6addr, he->h_addr_list[0], sizeof( struct in6_addr)); 309 } 310 return (0); 311 } 312 313 314 /* 315 * fill the addr and mask fields in the instruction as appropriate from av. 316 * Update length as appropriate. 317 * The following formats are allowed: 318 * any matches any IP6. Actually returns an empty instruction. 319 * me returns O_IP6_*_ME 320 * 321 * 03f1::234:123:0342 single IP6 address 322 * 03f1::234:123:0342/24 address/masklen 323 * 03f1::234:123:0342/ffff::ffff:ffff address/mask 324 * 03f1::234:123:0342/24,03f1::234:123:0343/ List of address 325 * 326 * Set of address (as in ipv6) not supported because ipv6 address 327 * are typically random past the initial prefix. 328 * Return 1 on success, 0 on failure. 329 */ 330 static int 331 fill_ip6(ipfw_insn_ip6 *cmd, char *av, int cblen, struct tidx *tstate) 332 { 333 int len = 0; 334 struct in6_addr *d = &(cmd->addr6); 335 char *oav; 336 /* 337 * Needed for multiple address. 338 * Note d[1] points to struct in6_add r mask6 of cmd 339 */ 340 341 cmd->o.len &= ~F_LEN_MASK; /* zero len */ 342 343 if (strcmp(av, "any") == 0) 344 return (1); 345 346 /* Set the data for "me" opt */ 347 if (strcmp(av, "me") == 0 || strcmp(av, "me6") == 0) { 348 cmd->o.len |= F_INSN_SIZE(ipfw_insn); 349 return (1); 350 } 351 352 if (strncmp(av, "table(", 6) == 0) { 353 fill_table(&cmd->o, av, O_IP_DST_LOOKUP, tstate); 354 return (1); 355 } 356 357 oav = av = strdup(av); 358 while (av) { 359 /* 360 * After the address we can have '/' indicating a mask, 361 * or ',' indicating another address follows. 362 */ 363 364 char *p, *q; 365 int masklen; 366 char md = '\0'; 367 368 CHECK_LENGTH(cblen, 369 1 + len + 2 * (int)F_INSN_SIZE(struct in6_addr)); 370 371 if ((q = strchr(av, ',')) ) { 372 *q = '\0'; 373 q++; 374 } 375 376 if ((p = strchr(av, '/')) ) { 377 md = *p; /* save the separator */ 378 *p = '\0'; /* terminate address string */ 379 p++; /* and skip past it */ 380 } 381 /* now p points to NULL, mask or next entry */ 382 383 /* lookup stores address in *d as a side effect */ 384 if (lookup_host6(av, d) != 0) { 385 /* XXX: failed. Free memory and go */ 386 errx(EX_DATAERR, "bad address \"%s\"", av); 387 } 388 /* next, look at the mask, if any */ 389 if (md == '/' && strchr(p, ':')) { 390 if (!inet_pton(AF_INET6, p, &d[1])) 391 errx(EX_DATAERR, "bad mask \"%s\"", p); 392 393 masklen = contigmask((uint8_t *)&(d[1]), 128); 394 } else { 395 masklen = (md == '/') ? atoi(p) : 128; 396 if (masklen > 128 || masklen < 0) 397 errx(EX_DATAERR, "bad width \"%s\''", p); 398 else 399 n2mask(&d[1], masklen); 400 } 401 402 APPLY_MASK(d, &d[1]); /* mask base address with mask */ 403 404 av = q; 405 406 /* Check this entry */ 407 if (masklen == 0) { 408 /* 409 * 'any' turns the entire list into a NOP. 410 * 'not any' never matches, so it is removed from the 411 * list unless it is the only item, in which case we 412 * report an error. 413 */ 414 if (cmd->o.len & F_NOT && av == NULL && len == 0) 415 errx(EX_DATAERR, "not any never matches"); 416 continue; 417 } 418 419 /* 420 * A single IP can be stored alone 421 */ 422 if (masklen == 128 && av == NULL && len == 0) { 423 len = F_INSN_SIZE(struct in6_addr); 424 break; 425 } 426 427 /* Update length and pointer to arguments */ 428 len += F_INSN_SIZE(struct in6_addr)*2; 429 d += 2; 430 } /* end while */ 431 432 /* 433 * Total length of the command, remember that 1 is the size of 434 * the base command. 435 */ 436 if (len + 1 > F_LEN_MASK) 437 errx(EX_DATAERR, "address list too long"); 438 cmd->o.len |= len+1; 439 free(oav); 440 return (1); 441 } 442 443 /* 444 * fills command for ipv6 flow-id filtering 445 * note that the 20 bit flow number is stored in a array of u_int32_t 446 * it's supported lists of flow-id, so in the o.arg1 we store how many 447 * additional flow-id we want to filter, the basic is 1 448 */ 449 void 450 fill_flow6( ipfw_insn_u32 *cmd, char *av, int cblen) 451 { 452 u_int32_t type; /* Current flow number */ 453 u_int16_t nflow = 0; /* Current flow index */ 454 char *s = av; 455 cmd->d[0] = 0; /* Initializing the base number*/ 456 457 while (s) { 458 CHECK_LENGTH(cblen, 459 (int)F_INSN_SIZE(ipfw_insn_u32) + nflow + 1); 460 461 av = strsep( &s, ",") ; 462 type = strtoul(av, &av, 0); 463 if (*av != ',' && *av != '\0') 464 errx(EX_DATAERR, "invalid ipv6 flow number %s", av); 465 if (type > 0xfffff) 466 errx(EX_DATAERR, "flow number out of range %s", av); 467 cmd->d[nflow] |= type; 468 nflow++; 469 } 470 if( nflow > 0 ) { 471 cmd->o.opcode = O_FLOW6ID; 472 cmd->o.len |= F_INSN_SIZE(ipfw_insn_u32) + nflow; 473 cmd->o.arg1 = nflow; 474 } 475 else { 476 errx(EX_DATAERR, "invalid ipv6 flow number %s", av); 477 } 478 } 479 480 ipfw_insn * 481 add_srcip6(ipfw_insn *cmd, char *av, int cblen, struct tidx *tstate) 482 { 483 484 fill_ip6((ipfw_insn_ip6 *)cmd, av, cblen, tstate); 485 if (cmd->opcode == O_IP_DST_SET) /* set */ 486 cmd->opcode = O_IP_SRC_SET; 487 else if (cmd->opcode == O_IP_DST_LOOKUP) /* table */ 488 cmd->opcode = O_IP_SRC_LOOKUP; 489 else if (F_LEN(cmd) == 0) { /* any */ 490 } else if (F_LEN(cmd) == F_INSN_SIZE(ipfw_insn)) { /* "me" */ 491 cmd->opcode = O_IP6_SRC_ME; 492 } else if (F_LEN(cmd) == 493 (F_INSN_SIZE(struct in6_addr) + F_INSN_SIZE(ipfw_insn))) { 494 /* single IP, no mask*/ 495 cmd->opcode = O_IP6_SRC; 496 } else { /* addr/mask opt */ 497 cmd->opcode = O_IP6_SRC_MASK; 498 } 499 return cmd; 500 } 501 502 ipfw_insn * 503 add_dstip6(ipfw_insn *cmd, char *av, int cblen, struct tidx *tstate) 504 { 505 506 fill_ip6((ipfw_insn_ip6 *)cmd, av, cblen, tstate); 507 if (cmd->opcode == O_IP_DST_SET) /* set */ 508 ; 509 else if (cmd->opcode == O_IP_DST_LOOKUP) /* table */ 510 ; 511 else if (F_LEN(cmd) == 0) { /* any */ 512 } else if (F_LEN(cmd) == F_INSN_SIZE(ipfw_insn)) { /* "me" */ 513 cmd->opcode = O_IP6_DST_ME; 514 } else if (F_LEN(cmd) == 515 (F_INSN_SIZE(struct in6_addr) + F_INSN_SIZE(ipfw_insn))) { 516 /* single IP, no mask*/ 517 cmd->opcode = O_IP6_DST; 518 } else { /* addr/mask opt */ 519 cmd->opcode = O_IP6_DST_MASK; 520 } 521 return cmd; 522 } 523