/* $OpenBSD: parse.y,v 1.20 2011/04/21 14:55:22 sthen Exp $ */ /* * Copyright (c) 2007, 2008 Reyk Floeter * Copyright (c) 2004, 2005 Esben Norby * Copyright (c) 2004 Ryan McBride * Copyright (c) 2002, 2003, 2004 Henning Brauer * Copyright (c) 2001 Markus Friedl. All rights reserved. * Copyright (c) 2001 Daniel Hartmeier. All rights reserved. * Copyright (c) 2001 Theo de Raadt. All rights reserved. * * 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 #include #include #include #include #include #include #include #include #include #include #include "snmpd.h" #include "mib.h" TAILQ_HEAD(files, file) files = TAILQ_HEAD_INITIALIZER(files); static struct file { TAILQ_ENTRY(file) entry; FILE *stream; char *name; int lineno; int errors; } *file, *topfile; struct file *pushfile(const char *, int); int popfile(void); int check_file_secrecy(int, const char *); int yyparse(void); int yylex(void); int yyerror(const char *, ...); int kw_cmp(const void *, const void *); int lookup(char *); int lgetc(int); int lungetc(int); int findeol(void); TAILQ_HEAD(symhead, sym) symhead = TAILQ_HEAD_INITIALIZER(symhead); struct sym { TAILQ_ENTRY(sym) entry; int used; int persist; char *nam; char *val; }; int symset(const char *, const char *, int); char *symget(const char *); struct snmpd *conf = NULL; static int errors = 0; static struct addresslist *hlist; struct address *host_v4(const char *); struct address *host_v6(const char *); int host_dns(const char *, struct addresslist *, int, in_port_t, struct ber_oid *, char *); int host(const char *, struct addresslist *, int, in_port_t, struct ber_oid *, char *); typedef struct { union { int64_t number; char *string; struct host *host; struct timeval tv; struct ber_oid *oid; struct { int type; void *data; long long value; } data; } v; int lineno; } YYSTYPE; %} %token INCLUDE %token LISTEN ON %token SYSTEM CONTACT DESCR LOCATION NAME OBJECTID SERVICES RTFILTER %token READONLY READWRITE OCTETSTRING INTEGER COMMUNITY TRAP RECEIVER %token ERROR %token STRING %token NUMBER %type hostcmn %type optwrite yesno %type objtype %type oid hostoid %% grammar : /* empty */ | grammar include '\n' | grammar '\n' | grammar varset '\n' | grammar main '\n' | grammar system '\n' | grammar mib '\n' | grammar error '\n' { file->errors++; } ; include : INCLUDE STRING { struct file *nfile; if ((nfile = pushfile($2, 0)) == NULL) { yyerror("failed to include file %s", $2); free($2); YYERROR; } free($2); file = nfile; lungetc('\n'); } ; varset : STRING '=' STRING { if (symset($1, $3, 0) == -1) fatal("cannot store variable"); free($1); free($3); } ; yesno : STRING { if (!strcmp($1, "yes")) $$ = 1; else if (!strcmp($1, "no")) $$ = 0; else { yyerror("syntax error, " "either yes or no expected"); free($1); YYERROR; } free($1); } ; main : LISTEN ON STRING { struct addresslist al; struct address *h; TAILQ_INIT(&al); if (host($3, &al, 1, SNMPD_PORT, NULL, NULL) <= 0) { yyerror("invalid ip address: %s", $3); free($3); YYERROR; } free($3); h = TAILQ_FIRST(&al); bcopy(&h->ss, &conf->sc_address.ss, sizeof(*h)); conf->sc_address.port = h->port; while ((h = TAILQ_FIRST(&al)) != NULL) { TAILQ_REMOVE(&al, h, entry); free(h); } } | READONLY COMMUNITY STRING { if (strlcpy(conf->sc_rdcommunity, $3, sizeof(conf->sc_rdcommunity)) >= sizeof(conf->sc_rdcommunity)) { yyerror("r/o community name too long"); free($3); YYERROR; } free($3); } | READWRITE COMMUNITY STRING { if (strlcpy(conf->sc_rwcommunity, $3, sizeof(conf->sc_rwcommunity)) >= sizeof(conf->sc_rwcommunity)) { yyerror("r/w community name too long"); free($3); YYERROR; } free($3); } | TRAP COMMUNITY STRING { if (strlcpy(conf->sc_trcommunity, $3, sizeof(conf->sc_trcommunity)) >= sizeof(conf->sc_trcommunity)) { yyerror("r/w community name too long"); free($3); YYERROR; } free($3); } | TRAP RECEIVER { hlist = &conf->sc_trapreceivers; } host { hlist = NULL; } | RTFILTER yesno { if ($2 == 1) conf->sc_rtfilter = ROUTE_FILTER(RTM_NEWADDR) | ROUTE_FILTER(RTM_DELADDR) | ROUTE_FILTER(RTM_IFINFO) | ROUTE_FILTER(RTM_IFANNOUNCE); else conf->sc_rtfilter = 0; } ; system : SYSTEM sysmib ; sysmib : CONTACT STRING { struct ber_oid o = OID(MIB_sysContact); mps_set(&o, $2, strlen($2)); } | DESCR STRING { struct ber_oid o = OID(MIB_sysDescr); mps_set(&o, $2, strlen($2)); } | LOCATION STRING { struct ber_oid o = OID(MIB_sysLocation); mps_set(&o, $2, strlen($2)); } | NAME STRING { struct ber_oid o = OID(MIB_sysName); mps_set(&o, $2, strlen($2)); } | OBJECTID oid { struct ber_oid o = OID(MIB_sysOID); mps_set(&o, $2, sizeof(struct ber_oid)); } | SERVICES NUMBER { struct ber_oid o = OID(MIB_sysServices); mps_set(&o, NULL, $2); } ; mib : OBJECTID oid NAME STRING optwrite objtype { struct oid *oid; if ((oid = (struct oid *) calloc(1, sizeof(*oid))) == NULL) { yyerror("calloc"); free($2); free($6.data); YYERROR; } smi_oidlen($2); bcopy($2, &oid->o_id, sizeof(struct ber_oid)); free($2); oid->o_name = $4; oid->o_data = $6.data; oid->o_val = $6.value; switch ($6.type) { case 1: oid->o_get = mps_getint; oid->o_set = mps_setint; break; case 2: oid->o_get = mps_getstr; oid->o_set = mps_setstr; break; } oid->o_flags = OID_RD|OID_DYNAMIC; if ($5) oid->o_flags |= OID_WR; smi_insert(oid); } ; objtype : INTEGER NUMBER { $$.type = 1; $$.data = NULL; $$.value = $2; } | OCTETSTRING STRING { $$.type = 2; $$.data = $2; $$.value = strlen($2); } ; optwrite : READONLY { $$ = 0; } | READWRITE { $$ = 1; } ; oid : STRING { struct ber_oid *sysoid; if ((sysoid = calloc(1, sizeof(*sysoid))) == NULL) { yyerror("calloc"); free($1); YYERROR; } if (ber_string2oid($1, sysoid) == -1) { yyerror("invalid OID: %s", $1); free(sysoid); free($1); YYERROR; } free($1); $$ = sysoid; } ; hostoid : /* empty */ { $$ = NULL; } | OBJECTID oid { $$ = $2; } ; hostcmn : /* empty */ { $$ = NULL; } | COMMUNITY STRING { $$ = $2; } ; hostdef : STRING hostoid hostcmn { if (host($1, hlist, 1, SNMPD_TRAPPORT, $2, $3) <= 0) { yyerror("invalid host: %s", $1); free($1); YYERROR; } free($1); } ; hostlist : /* empty */ | hostlist comma hostdef ; host : hostdef | '{' hostlist '}' ; comma : /* empty */ | ',' ; %% struct keywords { const char *k_name; int k_val; }; int yyerror(const char *fmt, ...) { va_list ap; file->errors++; va_start(ap, fmt); fprintf(stderr, "%s:%d: ", file->name, yylval.lineno); vfprintf(stderr, fmt, ap); fprintf(stderr, "\n"); va_end(ap); return (0); } int kw_cmp(const void *k, const void *e) { return (strcmp(k, ((const struct keywords *)e)->k_name)); } int lookup(char *s) { /* this has to be sorted always */ static const struct keywords keywords[] = { { "community", COMMUNITY }, { "contact", CONTACT }, { "description", DESCR }, { "filter-routes", RTFILTER }, { "include", INCLUDE }, { "integer", INTEGER }, { "listen", LISTEN }, { "location", LOCATION }, { "name", NAME }, { "oid", OBJECTID }, { "on", ON }, { "read-only", READONLY }, { "read-write", READWRITE }, { "receiver", RECEIVER }, { "services", SERVICES }, { "string", OCTETSTRING }, { "system", SYSTEM }, { "trap", TRAP } }; const struct keywords *p; p = bsearch(s, keywords, sizeof(keywords)/sizeof(keywords[0]), sizeof(keywords[0]), kw_cmp); if (p) return (p->k_val); else return (STRING); } #define MAXPUSHBACK 128 char *parsebuf; int parseindex; char pushback_buffer[MAXPUSHBACK]; int pushback_index = 0; int lgetc(int quotec) { int c, next; if (parsebuf) { /* Read character from the parsebuffer instead of input. */ if (parseindex >= 0) { c = parsebuf[parseindex++]; if (c != '\0') return (c); parsebuf = NULL; } else parseindex++; } if (pushback_index) return (pushback_buffer[--pushback_index]); if (quotec) { if ((c = getc(file->stream)) == EOF) { yyerror("reached end of file while parsing quoted string"); if (file == topfile || popfile() == EOF) return (EOF); return (quotec); } return (c); } while ((c = getc(file->stream)) == '\\') { next = getc(file->stream); if (next != '\n') { c = next; break; } yylval.lineno = file->lineno; file->lineno++; } if (c == '\t' || c == ' ') { /* Compress blanks to a single space. */ do { c = getc(file->stream); } while (c == '\t' || c == ' '); ungetc(c, file->stream); c = ' '; } while (c == EOF) { if (file == topfile || popfile() == EOF) return (EOF); c = getc(file->stream); } return (c); } int lungetc(int c) { if (c == EOF) return (EOF); if (parsebuf) { parseindex--; if (parseindex >= 0) return (c); } if (pushback_index < MAXPUSHBACK-1) return (pushback_buffer[pushback_index++] = c); else return (EOF); } int findeol(void) { int c; parsebuf = NULL; /* skip to either EOF or the first real EOL */ while (1) { if (pushback_index) c = pushback_buffer[--pushback_index]; else c = lgetc(0); if (c == '\n') { file->lineno++; break; } if (c == EOF) break; } return (ERROR); } int yylex(void) { char buf[8096]; char *p, *val; int quotec, next, c; int token; top: p = buf; while ((c = lgetc(0)) == ' ' || c == '\t') ; /* nothing */ yylval.lineno = file->lineno; if (c == '#') while ((c = lgetc(0)) != '\n' && c != EOF) ; /* nothing */ if (c == '$' && parsebuf == NULL) { while (1) { if ((c = lgetc(0)) == EOF) return (0); if (p + 1 >= buf + sizeof(buf) - 1) { yyerror("string too long"); return (findeol()); } if (isalnum(c) || c == '_') { *p++ = (char)c; continue; } *p = '\0'; lungetc(c); break; } val = symget(buf); if (val == NULL) { yyerror("macro '%s' not defined", buf); return (findeol()); } parsebuf = val; parseindex = 0; goto top; } switch (c) { case '\'': case '"': quotec = c; while (1) { if ((c = lgetc(quotec)) == EOF) return (0); if (c == '\n') { file->lineno++; continue; } else if (c == '\\') { if ((next = lgetc(quotec)) == EOF) return (0); if (next == quotec || c == ' ' || c == '\t') c = next; else if (next == '\n') { file->lineno++; continue; } else lungetc(next); } else if (c == quotec) { *p = '\0'; break; } if (p + 1 >= buf + sizeof(buf) - 1) { yyerror("string too long"); return (findeol()); } *p++ = (char)c; } yylval.v.string = strdup(buf); if (yylval.v.string == NULL) err(1, "yylex: strdup"); return (STRING); } #define allowed_to_end_number(x) \ (isspace(x) || x == ')' || x ==',' || x == '/' || x == '}' || x == '=') if (c == '-' || isdigit(c)) { do { *p++ = c; if ((unsigned)(p-buf) >= sizeof(buf)) { yyerror("string too long"); return (findeol()); } } while ((c = lgetc(0)) != EOF && isdigit(c)); lungetc(c); if (p == buf + 1 && buf[0] == '-') goto nodigits; if (c == EOF || allowed_to_end_number(c)) { const char *errstr = NULL; *p = '\0'; yylval.v.number = strtonum(buf, LLONG_MIN, LLONG_MAX, &errstr); if (errstr) { yyerror("\"%s\" invalid number: %s", buf, errstr); return (findeol()); } return (NUMBER); } else { nodigits: while (p > buf + 1) lungetc(*--p); c = *--p; if (c == '-') return (c); } } #define allowed_in_string(x) \ (isalnum(x) || (ispunct(x) && x != '(' && x != ')' && \ x != '{' && x != '}' && \ x != '!' && x != '=' && x != '#' && \ x != ',')) if (isalnum(c) || c == ':' || c == '_') { do { *p++ = c; if ((unsigned)(p-buf) >= sizeof(buf)) { yyerror("string too long"); return (findeol()); } } while ((c = lgetc(0)) != EOF && (allowed_in_string(c))); lungetc(c); *p = '\0'; if ((token = lookup(buf)) == STRING) if ((yylval.v.string = strdup(buf)) == NULL) err(1, "yylex: strdup"); return (token); } if (c == '\n') { yylval.lineno = file->lineno; file->lineno++; } if (c == EOF) return (0); return (c); } int check_file_secrecy(int fd, const char *fname) { struct stat st; if (fstat(fd, &st)) { log_warn("cannot stat %s", fname); return (-1); } if (st.st_uid != 0 && st.st_uid != getuid()) { log_warnx("%s: owner not root or current user", fname); return (-1); } if (st.st_mode & (S_IRWXG | S_IRWXO)) { log_warnx("%s: group/world readable/writeable", fname); return (-1); } return (0); } struct file * pushfile(const char *name, int secret) { struct file *nfile; if ((nfile = calloc(1, sizeof(struct file))) == NULL) { log_warn("malloc"); return (NULL); } if ((nfile->name = strdup(name)) == NULL) { log_warn("malloc"); free(nfile); return (NULL); } if ((nfile->stream = fopen(nfile->name, "r")) == NULL) { log_warn("%s", nfile->name); free(nfile->name); free(nfile); return (NULL); } else if (secret && check_file_secrecy(fileno(nfile->stream), nfile->name)) { fclose(nfile->stream); free(nfile->name); free(nfile); return (NULL); } nfile->lineno = 1; TAILQ_INSERT_TAIL(&files, nfile, entry); return (nfile); } int popfile(void) { struct file *prev; if ((prev = TAILQ_PREV(file, files, entry)) != NULL) prev->errors += file->errors; TAILQ_REMOVE(&files, file, entry); fclose(file->stream); free(file->name); free(file); file = prev; return (file ? 0 : EOF); } struct snmpd * parse_config(const char *filename, u_int flags) { struct sym *sym, *next; if ((conf = calloc(1, sizeof(*conf))) == NULL) { log_warn("cannot allocate memory"); return (NULL); } conf->sc_flags = flags; conf->sc_confpath = filename; conf->sc_address.ss.ss_family = AF_INET; conf->sc_address.port = SNMPD_PORT; strlcpy(conf->sc_rdcommunity, "public", SNMPD_MAXCOMMUNITYLEN); strlcpy(conf->sc_rwcommunity, "private", SNMPD_MAXCOMMUNITYLEN); strlcpy(conf->sc_trcommunity, "public", SNMPD_MAXCOMMUNITYLEN); TAILQ_INIT(&conf->sc_trapreceivers); if ((file = pushfile(filename, 0)) == NULL) { free(conf); return (NULL); } topfile = file; setservent(1); yyparse(); errors = file->errors; popfile(); endservent(); /* Free macros and check which have not been used. */ for (sym = TAILQ_FIRST(&symhead); sym != NULL; sym = next) { next = TAILQ_NEXT(sym, entry); if ((conf->sc_flags & SNMPD_F_VERBOSE) && !sym->used) fprintf(stderr, "warning: macro '%s' not " "used\n", sym->nam); if (!sym->persist) { free(sym->nam); free(sym->val); TAILQ_REMOVE(&symhead, sym, entry); free(sym); } } if (errors) { free(conf); return (NULL); } return (conf); } int symset(const char *nam, const char *val, int persist) { struct sym *sym; for (sym = TAILQ_FIRST(&symhead); sym && strcmp(nam, sym->nam); sym = TAILQ_NEXT(sym, entry)) ; /* nothing */ if (sym != NULL) { if (sym->persist == 1) return (0); else { free(sym->nam); free(sym->val); TAILQ_REMOVE(&symhead, sym, entry); free(sym); } } if ((sym = calloc(1, sizeof(*sym))) == NULL) return (-1); sym->nam = strdup(nam); if (sym->nam == NULL) { free(sym); return (-1); } sym->val = strdup(val); if (sym->val == NULL) { free(sym->nam); free(sym); return (-1); } sym->used = 0; sym->persist = persist; TAILQ_INSERT_TAIL(&symhead, sym, entry); return (0); } int cmdline_symset(char *s) { char *sym, *val; int ret; size_t len; if ((val = strrchr(s, '=')) == NULL) return (-1); len = strlen(s) - strlen(val) + 1; if ((sym = malloc(len)) == NULL) errx(1, "cmdline_symset: malloc"); (void)strlcpy(sym, s, len); ret = symset(sym, val + 1, 1); free(sym); return (ret); } char * symget(const char *nam) { struct sym *sym; TAILQ_FOREACH(sym, &symhead, entry) if (strcmp(nam, sym->nam) == 0) { sym->used = 1; return (sym->val); } return (NULL); } struct address * host_v4(const char *s) { struct in_addr ina; struct sockaddr_in *sain; struct address *h; bzero(&ina, sizeof(ina)); if (inet_pton(AF_INET, s, &ina) != 1) return (NULL); if ((h = calloc(1, sizeof(*h))) == NULL) fatal(NULL); sain = (struct sockaddr_in *)&h->ss; sain->sin_len = sizeof(struct sockaddr_in); sain->sin_family = AF_INET; sain->sin_addr.s_addr = ina.s_addr; return (h); } struct address * host_v6(const char *s) { struct addrinfo hints, *res; struct sockaddr_in6 *sa_in6; struct address *h = NULL; bzero(&hints, sizeof(hints)); hints.ai_family = AF_INET6; hints.ai_socktype = SOCK_DGRAM; /* dummy */ hints.ai_flags = AI_NUMERICHOST; if (getaddrinfo(s, "0", &hints, &res) == 0) { if ((h = calloc(1, sizeof(*h))) == NULL) fatal(NULL); sa_in6 = (struct sockaddr_in6 *)&h->ss; sa_in6->sin6_len = sizeof(struct sockaddr_in6); sa_in6->sin6_family = AF_INET6; memcpy(&sa_in6->sin6_addr, &((struct sockaddr_in6 *)res->ai_addr)->sin6_addr, sizeof(sa_in6->sin6_addr)); sa_in6->sin6_scope_id = ((struct sockaddr_in6 *)res->ai_addr)->sin6_scope_id; freeaddrinfo(res); } return (h); } int host_dns(const char *s, struct addresslist *al, int max, in_port_t port, struct ber_oid *oid, char *cmn) { struct addrinfo hints, *res0, *res; int error, cnt = 0; struct sockaddr_in *sain; struct sockaddr_in6 *sin6; struct address *h; bzero(&hints, sizeof(hints)); hints.ai_family = PF_UNSPEC; hints.ai_socktype = SOCK_DGRAM; /* DUMMY */ error = getaddrinfo(s, NULL, &hints, &res0); if (error == EAI_AGAIN || error == EAI_NODATA || error == EAI_NONAME) return (0); if (error) { log_warnx("host_dns: could not parse \"%s\": %s", s, gai_strerror(error)); return (-1); } for (res = res0; res && cnt < max; res = res->ai_next) { if (res->ai_family != AF_INET && res->ai_family != AF_INET6) continue; if ((h = calloc(1, sizeof(*h))) == NULL) fatal(NULL); h->port = port; if (oid != NULL) { if ((h->sa_oid = calloc(1, sizeof(*oid))) == NULL) fatal(NULL); bcopy(oid, h->sa_oid, sizeof(*oid)); } if (cmn != NULL) { if ((h->sa_community = strdup(cmn)) == NULL) fatal(NULL); } h->ss.ss_family = res->ai_family; if (res->ai_family == AF_INET) { sain = (struct sockaddr_in *)&h->ss; sain->sin_len = sizeof(struct sockaddr_in); sain->sin_addr.s_addr = ((struct sockaddr_in *) res->ai_addr)->sin_addr.s_addr; } else { sin6 = (struct sockaddr_in6 *)&h->ss; sin6->sin6_len = sizeof(struct sockaddr_in6); memcpy(&sin6->sin6_addr, &((struct sockaddr_in6 *) res->ai_addr)->sin6_addr, sizeof(struct in6_addr)); } TAILQ_INSERT_HEAD(al, h, entry); cnt++; } if (cnt == max && res) { log_warnx("host_dns: %s resolves to more than %d hosts", s, max); } freeaddrinfo(res0); if (oid != NULL) free(oid); if (cmn != NULL) free(cmn); return (cnt); } int host(const char *s, struct addresslist *al, int max, in_port_t port, struct ber_oid *oid, char *cmn) { struct address *h; h = host_v4(s); /* IPv6 address? */ if (h == NULL) h = host_v6(s); if (h != NULL) { h->port = port; h->sa_oid = oid; h->sa_community = cmn; TAILQ_INSERT_HEAD(al, h, entry); return (1); } return (host_dns(s, al, max, port, oid, cmn)); }