From 4da84a5bb3c9969a589fa60e63338461254a86f3 Mon Sep 17 00:00:00 2001 From: "Andrey V. Elsukov" Date: Wed, 1 May 2019 09:05:48 +0000 Subject: [PATCH] MFC r345843: Follow the declared behaviour that specifies server string format in bsnmpclient(3). snmp_parse_server() function accepts string where some fields can be omitted: [trans::][community@][server][:port] "trans" field can be "udp", "udp6", "dgram" and "stream". "community" can be empty string, if it is omitted, the default value will be used. For read_community it is "public", for write_comminity it is "private". "server" field can be hostname, IPv4 address or IPv6 address. IPv6 address should be specified in brackets "[]". If port is omitted, the default value "snmp" will be used for "udp" and "udp6" transports. So, now for bsnmpget(1) and bsnmwalk(1) it is not required to specify all fields in argument of '-s' option. E.g. # bsnmpget -s 127.1 sysName.0 # bsnmpget -s "udp::127.1" sysName.0 # bsnmpget -s "udp::public@127.1" sysName.0 # bsnmpget -s "udp::public@127.1:161" sysName.0 # bsnmpget -s "udp::[::1]" sysName.0 # bsnmpget -s "udp6::[::1]" sysName.0 # bsnmpget -s "[fe80::1%lo0]" sysName.0 PR: 236664 Reported by: olivier --- contrib/bsnmp/lib/snmpclient.c | 128 +++++++++++++++++---------------- 1 file changed, 65 insertions(+), 63 deletions(-) diff --git a/contrib/bsnmp/lib/snmpclient.c b/contrib/bsnmp/lib/snmpclient.c index 0c559bf2c1f..285ffdb4c1b 100644 --- a/contrib/bsnmp/lib/snmpclient.c +++ b/contrib/bsnmp/lib/snmpclient.c @@ -1874,38 +1874,47 @@ snmp_client_set_port(struct snmp_client *cl, const char *p) return (0); } +static const char *const trans_list[] = { + [SNMP_TRANS_UDP] = "udp::", + [SNMP_TRANS_LOC_DGRAM] = "dgram::", + [SNMP_TRANS_LOC_STREAM] = "stream::", + [SNMP_TRANS_UDP6] = "udp6::", +}; + /** * Try to get a transport identifier which is a leading alphanumeric string - * (starting with '_' or a letter and including also '_') terminated by - * a double colon. The string may not be empty. The transport identifier - * is optional. + * terminated by a double colon. The string may not be empty. The transport + * identifier is optional. * * \param sc client struct to set errors * \param strp possible start of transport; updated to point to * the next character to parse * - * \return end of transport; equals *strp if there is none; NULL if there - * was an error + * \return transport identifier */ -static inline const char * +static inline int get_transp(struct snmp_client *sc, const char **strp) { - const char *p = *strp; + const char *p; + size_t i; - if (isascii(*p) && (isalpha(*p) || *p == '_')) { - p++; - while (isascii(*p) && (isalnum(*p) || *p == '_')) - p++; - if (p[0] == ':' && p[1] == ':') { - *strp = p + 2; - return (p); + for (i = 0; i < nitems(trans_list); i++) { + if (trans_list[i] == NULL || *trans_list[i] == '\0') + continue; + p = strstr(*strp, trans_list[i]); + if (p == *strp) { + *strp += strlen(trans_list[i]); + return ((int)i); } } + + p = *strp; if (p[0] == ':' && p[1] == ':') { seterr(sc, "empty transport specifier"); - return (NULL); + return (-1); } - return (*strp); + /* by default assume UDP */ + return (SNMP_TRANS_UDP); } /** @@ -2143,24 +2152,13 @@ save_str(struct snmp_client *sc, const char *const s[2]) int snmp_parse_server(struct snmp_client *sc, const char *str) { -#if DEBUG_PARSE const char *const orig = str; -#endif - - const char *const trans_list[] = { - [SNMP_TRANS_UDP] = "udp", - [SNMP_TRANS_LOC_DGRAM] = "dgram", - [SNMP_TRANS_LOC_STREAM] = "stream", - [SNMP_TRANS_UDP6] = "udp6", - }; - /* parse input */ - const char *const transp[2] = { - str, - get_transp(sc, &str), - }; - if (transp[1] == NULL) + int i, trans = get_transp(sc, &str); + if (trans < 0) return (-1); + /* choose automatically */ + i = orig == str ? -1: trans; const char *const comm[2] = { str, @@ -2206,7 +2204,7 @@ snmp_parse_server(struct snmp_client *sc, const char *str) } #if DEBUG_PARSE - printf("transp: %zu %zu\n", transp[0] - orig, transp[1] - orig); + printf("transp: %u\n", trans); printf("comm: %zu %zu\n", comm[0] - orig, comm[1] - orig); printf("ipv6: %zu %zu\n", ipv6[0] - orig, ipv6[1] - orig); printf("ipv4: %zu %zu\n", ipv4[0] - orig, ipv4[1] - orig); @@ -2215,69 +2213,73 @@ snmp_parse_server(struct snmp_client *sc, const char *str) #endif /* analyse and allocate */ - int i = -1; - if (transp[0] != transp[1]) { - for (i = 0; i < (int)nitems(trans_list); i++) { - if (trans_list[i] != NULL && - strlen(trans_list[i]) == (size_t)(transp[1] - - transp[0]) && !strncmp(trans_list[i], transp[0], - transp[1] - transp[0])) - break; - } - - if (i == (int)nitems(trans_list)) { - seterr(sc, "unknown transport specifier '%.*s'", - transp[1] - transp[0], transp[0]); - return (-1); - } - } - char *chost; if (ipv6[0] != ipv6[1]) { if ((chost = save_str(sc, ipv6)) == NULL) return (-1); - if (i == -1) - i = SNMP_TRANS_UDP6; + if (i == -1 || trans == SNMP_TRANS_UDP) + trans = SNMP_TRANS_UDP6; } else if (ipv4[0] != ipv4[1]) { if ((chost = save_str(sc, ipv4)) == NULL) return (-1); if (i == -1) - i = SNMP_TRANS_UDP; + trans = SNMP_TRANS_UDP; } else { if ((chost = save_str(sc, host)) == NULL) return (-1); if (i == -1) { - /* Default transport is UDP unless the host contains - * a slash in which case we default to DGRAM. */ - i = SNMP_TRANS_UDP; + /* + * Default transport is UDP unless the host contains + * a slash in which case we default to DGRAM. + */ for (const char *p = host[0]; p < host[1]; p++) if (*p == '/') { - i = SNMP_TRANS_LOC_DGRAM; + trans = SNMP_TRANS_LOC_DGRAM; break; } } } - char *cport = save_str(sc, port); + char *cport; + + if (port[0] == port[1] && ( + trans == SNMP_TRANS_UDP || trans == SNMP_TRANS_UDP6)) { + /* If port was not specified, use "snmp" name by default */ + cport = strdup("snmp"); + } else + cport = save_str(sc, port); + if (cport == NULL) { free(chost); return (-1); } /* commit */ - sc->trans = i; - - strncpy(sc->read_community, comm[0], comm[1] - comm[0]); - sc->read_community[comm[1] - comm[0]] = '\0'; - strncpy(sc->write_community, comm[0], comm[1] - comm[0]); - sc->write_community[comm[1] - comm[0]] = '\0'; + sc->trans = trans; + /* + * If community string was specified and it is empty, overwrite it. + * If it was not specified, use default. + */ + if (comm[0] != comm[1] || strrchr(comm[0], '@') != NULL) { + strncpy(sc->read_community, comm[0], comm[1] - comm[0]); + sc->read_community[comm[1] - comm[0]] = '\0'; + strncpy(sc->write_community, comm[0], comm[1] - comm[0]); + sc->write_community[comm[1] - comm[0]] = '\0'; + } free(sc->chost); sc->chost = chost; free(sc->cport); sc->cport = cport; +#if DEBUG_PARSE + printf("Committed values:\n"); + printf("trans: %u\n", sc->trans); + printf("comm: '%s'/'%s'\n", sc->read_community, sc->write_community); + printf("host: '%s'\n", sc->chost); + printf("port: '%s'\n", sc->cport); +#endif return (0); } -- 2.45.0