/* $OpenBSD: parser.c,v 1.29 2006/03/22 10:25:49 claudio Exp $ */ /* * Copyright (c) 2003, 2004 Henning Brauer * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ #include #include #include #include #include #include #include #include #include #include "parser.h" enum token_type { NOTOKEN, ENDTOKEN, KEYWORD, ADDRESS, FLAG, ASNUM, ASTYPE, PREFIX, PEERDESC, COMMUNITY, LOCALPREF, MED, NEXTHOP, PFTABLE, PREPNBR, PREPSELF, WEIGHT, FAMILY }; struct token { enum token_type type; const char *keyword; int value; const struct token *next; }; static const struct token t_main[]; static const struct token t_show[]; static const struct token t_show_summary[]; static const struct token t_show_fib[]; static const struct token t_show_rib[]; static const struct token t_show_neighbor[]; static const struct token t_show_neighbor_modifiers[]; static const struct token t_fib[]; static const struct token t_neighbor[]; static const struct token t_neighbor_modifiers[]; static const struct token t_show_as[]; static const struct token t_show_prefix[]; static const struct token t_show_ip[]; static const struct token t_network[]; static const struct token t_network_show[]; static const struct token t_prefix[]; static const struct token t_set[]; static const struct token t_community[]; static const struct token t_localpref[]; static const struct token t_med[]; static const struct token t_nexthop[]; static const struct token t_pftable[]; static const struct token t_prepnbr[]; static const struct token t_prepself[]; static const struct token t_weight[]; static const struct token t_main[] = { { KEYWORD, "reload", RELOAD, NULL}, { KEYWORD, "show", SHOW, t_show}, { KEYWORD, "fib", FIB, t_fib}, { KEYWORD, "neighbor", NEIGHBOR, t_neighbor}, { KEYWORD, "network", NONE, t_network}, { ENDTOKEN, "", NONE, NULL} }; static const struct token t_show[] = { { NOTOKEN, "", NONE, NULL}, { KEYWORD, "fib", SHOW_FIB, t_show_fib}, { KEYWORD, "interfaces", SHOW_INTERFACE, NULL}, { KEYWORD, "neighbor", SHOW_NEIGHBOR, t_show_neighbor}, { KEYWORD, "network", NETWORK_SHOW, t_network_show}, { KEYWORD, "nexthop", SHOW_NEXTHOP, NULL}, { KEYWORD, "rib", SHOW_RIB, t_show_rib}, { KEYWORD, "ip", NONE, t_show_ip}, { KEYWORD, "summary", SHOW_SUMMARY, t_show_summary}, { ENDTOKEN, "", NONE, NULL} }; static const struct token t_show_summary[] = { { NOTOKEN, "", NONE, NULL}, { KEYWORD, "terse", SHOW_SUMMARY_TERSE, NULL}, { ENDTOKEN, "", NONE, NULL} }; static const struct token t_show_fib[] = { { NOTOKEN, "", NONE, NULL}, { FLAG, "connected", F_CONNECTED, t_show_fib}, { FLAG, "static", F_STATIC, t_show_fib}, { FLAG, "bgp", F_BGPD_INSERTED, t_show_fib}, { FLAG, "nexthop", F_NEXTHOP, t_show_fib}, { FAMILY, "", NONE, t_show_fib}, { ADDRESS, "", NONE, NULL}, { ENDTOKEN, "", NONE, NULL} }; static const struct token t_show_rib[] = { { NOTOKEN, "", NONE, NULL}, { PREFIX, "", NONE, t_show_prefix}, { ASTYPE, "as", AS_ALL, t_show_as}, { ASTYPE, "source-as", AS_SOURCE, t_show_as}, { ASTYPE, "transit-as", AS_TRANSIT, t_show_as}, { ASTYPE, "empty-as", AS_EMPTY, NULL}, { KEYWORD, "summary", SHOW_SUMMARY, NULL}, { FLAG, "detail", F_CTL_DETAIL, t_show_rib}, { KEYWORD, "memory", SHOW_RIB_MEM, NULL}, { FAMILY, "", NONE, NULL}, { ENDTOKEN, "", NONE, NULL} }; static const struct token t_show_neighbor[] = { { NOTOKEN, "", NONE, NULL}, { ADDRESS, "", NONE, t_show_neighbor_modifiers}, { PEERDESC, "", NONE, t_show_neighbor_modifiers}, { ENDTOKEN, "", NONE, NULL} }; static const struct token t_show_neighbor_modifiers[] = { { NOTOKEN, "", NONE, NULL}, { KEYWORD, "timers", SHOW_NEIGHBOR_TIMERS, NULL}, { KEYWORD, "messages", SHOW_NEIGHBOR, NULL}, { ENDTOKEN, "", NONE, NULL} }; static const struct token t_fib[] = { { KEYWORD, "couple", FIB_COUPLE, NULL}, { KEYWORD, "decouple", FIB_DECOUPLE, NULL}, { ENDTOKEN, "", NONE, NULL} }; static const struct token t_neighbor[] = { { ADDRESS, "", NONE, t_neighbor_modifiers}, { PEERDESC, "", NONE, t_neighbor_modifiers}, { ENDTOKEN, "", NONE, NULL} }; static const struct token t_neighbor_modifiers[] = { { KEYWORD, "up", NEIGHBOR_UP, NULL}, { KEYWORD, "down", NEIGHBOR_DOWN, NULL}, { KEYWORD, "clear", NEIGHBOR_CLEAR, NULL}, { ENDTOKEN, "", NONE, NULL} }; static const struct token t_show_as[] = { { ASNUM, "", NONE, NULL}, { ENDTOKEN, "", NONE, NULL} }; static const struct token t_show_prefix[] = { { NOTOKEN, "", NONE, NULL}, { FLAG, "all", F_LONGER, NULL}, { FLAG, "longer-prefixes", F_LONGER, NULL}, { ENDTOKEN, "", NONE, NULL} }; static const struct token t_show_ip[] = { { KEYWORD, "bgp", SHOW_RIB, t_show_rib}, { ENDTOKEN, "", NONE, NULL} }; static const struct token t_network[] = { { KEYWORD, "add", NETWORK_ADD, t_prefix}, { KEYWORD, "delete", NETWORK_REMOVE, t_prefix}, { KEYWORD, "flush", NETWORK_FLUSH, NULL}, { KEYWORD, "show", NETWORK_SHOW, t_network_show}, { ENDTOKEN, "", NONE, NULL} }; static const struct token t_prefix[] = { { PREFIX, "", NONE, t_set}, { ENDTOKEN, "", NONE, NULL} }; static const struct token t_network_show[] = { { NOTOKEN, "", NONE, NULL}, { FAMILY, "", NONE, NULL}, { ENDTOKEN, "", NONE, NULL} }; static const struct token t_set[] = { { NOTOKEN, "", NONE, NULL}, { KEYWORD, "community", NONE, t_community}, { KEYWORD, "localpref", NONE, t_localpref}, { KEYWORD, "med", NONE, t_med}, { KEYWORD, "metric", NONE, t_med}, { KEYWORD, "nexthop", NONE, t_nexthop}, { KEYWORD, "pftable", NONE, t_pftable}, { KEYWORD, "prepend-neighbor", NONE, t_prepnbr}, { KEYWORD, "prepend-self", NONE, t_prepself}, { KEYWORD, "weight", NONE, t_weight}, { ENDTOKEN, "", NONE, NULL} }; static const struct token t_community[] = { { COMMUNITY, "", NONE, t_set}, { ENDTOKEN, "", NONE, NULL} }; static const struct token t_localpref[] = { { LOCALPREF, "", NONE, t_set}, { ENDTOKEN, "", NONE, NULL} }; static const struct token t_med[] = { { MED, "", NONE, t_set}, { ENDTOKEN, "", NONE, NULL} }; static const struct token t_nexthop[] = { { NEXTHOP, "", NONE, t_set}, { ENDTOKEN, "", NONE, NULL} }; static const struct token t_pftable[] = { { PFTABLE, "", NONE, t_set}, { ENDTOKEN, "", NONE, NULL} }; static const struct token t_prepnbr[] = { { PREPNBR, "", NONE, t_set}, { ENDTOKEN, "", NONE, NULL} }; static const struct token t_prepself[] = { { PREPSELF, "", NONE, t_set}, { ENDTOKEN, "", NONE, NULL} }; static const struct token t_weight[] = { { WEIGHT, "", NONE, t_set}, { ENDTOKEN, "", NONE, NULL} }; static struct parse_result res; const struct token *match_token(const char *, const struct token []); void show_valid_args(const struct token []); int parse_addr(const char *, struct bgpd_addr *); int parse_prefix(const char *, struct bgpd_addr *, u_int8_t *); int parse_asnum(const char *, u_int16_t *); int parse_number(const char *, struct parse_result *, enum token_type); int getcommunity(const char *); int parse_community(const char *, struct parse_result *); int parse_nexthop(const char *, struct parse_result *); struct parse_result * parse(int argc, char *argv[]) { const struct token *table = t_main; const struct token *match; bzero(&res, sizeof(res)); TAILQ_INIT(&res.set); while (argc > 0) { if ((match = match_token(argv[0], table)) == NULL) { fprintf(stderr, "valid commands/args:\n"); show_valid_args(table); return (NULL); } argc--; argv++; if (match->type == NOTOKEN || match->next == NULL) break; table = match->next; } if (argc > 0) { fprintf(stderr, "superfluous argument: %s\n", argv[0]); return (NULL); } return (&res); } const struct token * match_token(const char *word, const struct token table[]) { u_int i, match; const struct token *t = NULL; struct filter_set *fs; match = 0; for (i = 0; table[i].type != ENDTOKEN; i++) { switch (table[i].type) { case NOTOKEN: if (word == NULL || strlen(word) == 0) { match++; t = &table[i]; } break; case KEYWORD: if (word != NULL && strncmp(word, table[i].keyword, strlen(word)) == 0) { match++; t = &table[i]; if (t->value) res.action = t->value; } break; case FLAG: if (word != NULL && strncmp(word, table[i].keyword, strlen(word)) == 0) { match++; t = &table[i]; res.flags |= t->value; } break; case FAMILY: if (word == NULL) break; if (!strcmp(word, "inet") || !strcmp(word, "IPv4")) { match++; t = &table[i]; res.af = AF_INET; } if (!strcmp(word, "inet6") || !strcmp(word, "IPv6")) { match++; t = &table[i]; res.af = AF_INET6; } break; case ADDRESS: if (parse_addr(word, &res.addr)) { match++; t = &table[i]; if (t->value) res.action = t->value; } break; case PREFIX: if (parse_prefix(word, &res.addr, &res.prefixlen)) { match++; t = &table[i]; if (t->value) res.action = t->value; } break; case ASTYPE: if (word != NULL && strncmp(word, table[i].keyword, strlen(word)) == 0) { match++; t = &table[i]; res.as.type = t->value; } break; case ASNUM: if (parse_asnum(word, &res.as.as)) { match++; t = &table[i]; } break; case PEERDESC: if (!match && word != NULL && strlen(word) > 0) { if (strlcpy(res.peerdesc, word, sizeof(res.peerdesc)) >= sizeof(res.peerdesc)) errx(1, "neighbor description too " "long"); match++; t = &table[i]; } break; case COMMUNITY: if (word != NULL && strlen(word) > 0 && parse_community(word, &res)) { match++; t = &table[i]; } break; case LOCALPREF: case MED: case PREPNBR: case PREPSELF: case WEIGHT: if (word != NULL && strlen(word) > 0 && parse_number(word, &res, table[i].type)) { match++; t = &table[i]; } break; case NEXTHOP: if (word != NULL && strlen(word) > 0 && parse_nexthop(word, &res)) { match++; t = &table[i]; } break; case PFTABLE: if (word != NULL && strlen(word) > 0) { if ((fs = calloc(1, sizeof(struct filter_set))) == NULL) err(1, NULL); if (strlcpy(fs->action.pftable, word, sizeof(fs->action.pftable)) >= sizeof(fs->action.pftable)) errx(1, "pftable name too long"); TAILQ_INSERT_TAIL(&res.set, fs, entry); match++; t = &table[i]; } break; case ENDTOKEN: break; } } if (match != 1) { if (match > 1) fprintf(stderr, "ambiguous argument: %s\n", word); if (match < 1) fprintf(stderr, "unknown argument: %s\n", word); return (NULL); } return (t); } void show_valid_args(const struct token table[]) { int i; for (i = 0; table[i].type != ENDTOKEN; i++) { switch (table[i].type) { case NOTOKEN: fprintf(stderr, " \n"); break; case KEYWORD: case FLAG: case ASTYPE: fprintf(stderr, " %s\n", table[i].keyword); break; case ADDRESS: fprintf(stderr, "
\n"); break; case PREFIX: fprintf(stderr, "
[/]\n"); break; case ASNUM: fprintf(stderr, " \n"); break; case PEERDESC: fprintf(stderr, " \n"); break; case COMMUNITY: fprintf(stderr, " \n"); break; case LOCALPREF: case MED: case PREPNBR: case PREPSELF: case WEIGHT: fprintf(stderr, " \n"); break; case NEXTHOP: fprintf(stderr, "
\n"); break; case PFTABLE: fprintf(stderr, " \n"); break; case FAMILY: fprintf(stderr, " [ inet | inet6 | IPv4 | IPv6 ]\n"); case ENDTOKEN: break; } } } int parse_addr(const char *word, struct bgpd_addr *addr) { struct in_addr ina; struct addrinfo hints, *r; if (word == NULL) return (0); bzero(addr, sizeof(struct bgpd_addr)); bzero(&ina, sizeof(ina)); if (inet_pton(AF_INET, word, &ina) == 1) { addr->af = AF_INET; addr->v4 = ina; return (1); } bzero(&hints, sizeof(hints)); hints.ai_family = AF_INET6; hints.ai_socktype = SOCK_DGRAM; /*dummy*/ hints.ai_flags = AI_NUMERICHOST; if (getaddrinfo(word, "0", &hints, &r) == 0) { addr->af = AF_INET6; memcpy(&addr->v6, &((struct sockaddr_in6 *)r->ai_addr)->sin6_addr, sizeof(addr->v6)); addr->scope_id = ((struct sockaddr_in6 *)r->ai_addr)->sin6_scope_id; freeaddrinfo(r); return (1); } return (0); } int parse_prefix(const char *word, struct bgpd_addr *addr, u_int8_t *prefixlen) { char *p, *ps; const char *errstr; int mask = -1; if (word == NULL) return (0); bzero(addr, sizeof(struct bgpd_addr)); if ((p = strrchr(word, '/')) != NULL) { mask = strtonum(p + 1, 0, 128, &errstr); if (errstr) errx(1, "invalid netmask: %s", errstr); if ((ps = malloc(strlen(word) - strlen(p) + 1)) == NULL) err(1, "host: malloc"); strlcpy(ps, word, strlen(word) - strlen(p) + 1); if (parse_addr(ps, addr) == 0) return (0); free(ps); } else if (parse_addr(word, addr) == 0) return (0); switch (addr->af) { case AF_INET: if (mask == -1) mask = 32; if (mask > 32) errx(1, "invalid netmask: too large"); addr->v4.s_addr = addr->v4.s_addr & htonl(prefixlen2mask(mask)); break; case AF_INET6: if (mask == -1) mask = 128; inet6applymask(&addr->v6, &addr->v6, mask); break; default: return (0); } *prefixlen = mask; return (1); } int parse_asnum(const char *word, u_int16_t *asnum) { u_long ulval; char *ep; if (word == NULL) return (0); errno = 0; ulval = strtoul(word, &ep, 0); if (word[0] == '\0' || *ep != '\0') return (0); if (errno == ERANGE && ulval == ULONG_MAX) return (0); if (ulval > USHRT_MAX) return (0); *asnum = (u_int16_t)ulval; return (1); } int parse_number(const char *word, struct parse_result *r, enum token_type type) { struct filter_set *fs; u_long ulval; char *ep; if (word == NULL) return (0); errno = 0; ulval = strtoul(word, &ep, 0); if (word[0] == '\0' || *ep != '\0') return (0); if (errno == ERANGE && ulval == ULONG_MAX) return (0); if (ulval > UINT_MAX) return (0); /* number was parseable */ if ((fs = calloc(1, sizeof(struct filter_set))) == NULL) err(1, NULL); switch (type) { case LOCALPREF: fs->type = ACTION_SET_LOCALPREF; fs->action.metric = ulval; break; case MED: fs->type = ACTION_SET_MED; fs->action.metric = ulval; break; case PREPNBR: if (ulval > 128) { free(fs); return (0); } fs->type = ACTION_SET_PREPEND_PEER; fs->action.prepend = ulval; break; case PREPSELF: if (ulval > 128) { free(fs); return (0); } fs->type = ACTION_SET_PREPEND_SELF; fs->action.prepend = ulval; break; case WEIGHT: fs->type = ACTION_SET_WEIGHT; fs->action.metric = ulval; break; default: errx(1, "king bula sez bad things happen"); } TAILQ_INSERT_TAIL(&r->set, fs, entry); return (1); } int getcommunity(const char *s) { char *ep; u_long ulval; if (strcmp(s, "*") == 0) return (COMMUNITY_ANY); errno = 0; ulval = strtoul(s, &ep, 0); if (s[0] == '\0' || *ep != '\0') return (COMMUNITY_ERROR); if (errno == ERANGE && ulval == ULONG_MAX) return (COMMUNITY_ERROR); if (ulval > USHRT_MAX) return (COMMUNITY_ERROR); return (ulval); } int parse_community(const char *word, struct parse_result *r) { struct filter_set *fs; char *p; int i; u_int16_t as, type; /* Well-known communities */ if (strcasecmp(word, "NO_EXPORT") == 0) { as = COMMUNITY_WELLKNOWN; type = COMMUNITY_NO_EXPORT; goto done; } else if (strcasecmp(word, "NO_ADVERTISE") == 0) { as = COMMUNITY_WELLKNOWN; type = COMMUNITY_NO_ADVERTISE; goto done; } else if (strcasecmp(word, "NO_EXPORT_SUBCONFED") == 0) { as = COMMUNITY_WELLKNOWN; type = COMMUNITY_NO_EXPSUBCONFED; goto done; } else if (strcasecmp(word, "NO_PEER") == 0) { as = COMMUNITY_WELLKNOWN; type = COMMUNITY_NO_PEER; goto done; } if ((p = strchr(word, ':')) == NULL) { fprintf(stderr, "Bad community syntax\n"); return (0); } *p++ = 0; if ((i = getcommunity(word)) == COMMUNITY_ERROR) { fprintf(stderr, "\"%s\" is not a number or too big", word); return (0); } as = i; if ((i = getcommunity(p)) == COMMUNITY_ERROR) { fprintf(stderr, "\"%s\" is not a number or too big", p); return (0); } type = i; done: if (as == 0 || as == USHRT_MAX) { fprintf(stderr, "Invalid community\n"); return (0); } if (as == COMMUNITY_WELLKNOWN) switch (type) { case COMMUNITY_NO_EXPORT: case COMMUNITY_NO_ADVERTISE: case COMMUNITY_NO_EXPSUBCONFED: /* valid */ break; default: /* unknown */ fprintf(stderr, "Invalid well-known community\n"); return (0); } if ((fs = calloc(1, sizeof(struct filter_set))) == NULL) err(1, NULL); fs->type = ACTION_SET_COMMUNITY; fs->action.community.as = as; fs->action.community.type = type; TAILQ_INSERT_TAIL(&r->set, fs, entry); return (1); } int parse_nexthop(const char *word, struct parse_result *r) { struct filter_set *fs; if ((fs = calloc(1, sizeof(struct filter_set))) == NULL) err(1, NULL); if (strcmp(word, "blackhole") == 0) fs->type = ACTION_SET_NEXTHOP_BLACKHOLE; else if (strcmp(word, "reject") == 0) fs->type = ACTION_SET_NEXTHOP_REJECT; else if (strcmp(word, "no-modify") == 0) fs->type = ACTION_SET_NEXTHOP_NOMODIFY; else if (parse_addr(word, &fs->action.nexthop)) { fs->type = ACTION_SET_NEXTHOP; } else { free(fs); return (0); } TAILQ_INSERT_TAIL(&r->set, fs, entry); return (1); } /* XXX local copies from kroute.c, should go to a shared file */ in_addr_t prefixlen2mask(u_int8_t prefixlen) { if (prefixlen == 0) return (0); return (0xffffffff << (32 - prefixlen)); } void inet6applymask(struct in6_addr *dest, const struct in6_addr *src, int prefixlen) { struct in6_addr mask; int i; bzero(&mask, sizeof(mask)); for (i = 0; i < prefixlen / 8; i++) mask.s6_addr[i] = 0xff; i = prefixlen % 8; if (i) mask.s6_addr[prefixlen / 8] = 0xff00 >> i; for (i = 0; i < 16; i++) dest->s6_addr[i] = src->s6_addr[i] & mask.s6_addr[i]; }