diff options
| -rw-r--r-- | include/xtables.h.in | 6 | ||||
| -rw-r--r-- | xtoptions.c | 51 |
2 files changed, 56 insertions, 1 deletions
diff --git a/include/xtables.h.in b/include/xtables.h.in index d8a31245..a9a9ffad 100644 --- a/include/xtables.h.in +++ b/include/xtables.h.in @@ -53,6 +53,8 @@ struct in_addr; * %XTTYPE_MARKMASK32: 32-bit mark with optional mask * %XTTYPE_SYSLOGLEVEL: syslog level by name or number * %XTTYPE_ONEHOST: one host or address (union nf_inet_addr) + * %XTTYPE_PORT: 16-bit port name or number + * %XTTYPE_PORT_NE: 16-bit port name or number, stored as network-endian */ enum xt_option_type { XTTYPE_NONE, @@ -68,6 +70,8 @@ enum xt_option_type { XTTYPE_MARKMASK32, XTTYPE_SYSLOGLEVEL, XTTYPE_ONEHOST, + XTTYPE_PORT, + XTTYPE_PORT_NE, }; /** @@ -123,7 +127,7 @@ struct xt_option_call { uint8_t nvals; union { uint8_t u8, u8_range[2], syslog_level; - uint16_t u16, u16_range[2]; + uint16_t u16, u16_range[2], port; uint32_t u32, u32_range[2]; uint64_t u64, u64_range[2]; union nf_inet_addr inetaddr; diff --git a/xtoptions.c b/xtoptions.c index e0c3213f..c3cc40e6 100644 --- a/xtoptions.c +++ b/xtoptions.c @@ -354,6 +354,53 @@ static void xtopt_parse_onehost(struct xt_option_call *cb) sizeof(cb->val.inetaddr)); } +/** + * @name: port name, or number as a string (e.g. "http" or "80") + * + * Resolve a port name to a number. Returns the port number in integral + * form on success, or <0 on error. (errno will not be set.) + */ +static int xtables_getportbyname(const char *name) +{ + struct addrinfo *res = NULL, *p; + int ret; + + ret = getaddrinfo(NULL, name, NULL, &res); + if (ret < 0) + return -1; + ret = -1; + for (p = res; p != NULL; p = p->ai_next) { + if (p->ai_family == AF_INET6) { + ret = ((struct sockaddr_in6 *)p->ai_addr)->sin6_port; + break; + } else if (p->ai_family == AF_INET) { + ret = ((struct sockaddr_in *)p->ai_addr)->sin_port; + break; + } + } + freeaddrinfo(res); + return ntohs(ret); +} + +/** + * Validate and parse a port specification and put the result into @cb. + */ +static void xtopt_parse_port(struct xt_option_call *cb) +{ + int ret; + + ret = xtables_getportbyname(cb->arg); + if (ret < 0) + xt_params->exit_err(PARAMETER_PROBLEM, + "Port \"%s\" does not resolve to anything.\n", + cb->arg); + cb->val.port = ret; + if (cb->entry->type == XTTYPE_PORT_NE) + cb->val.port = htons(cb->val.port); + if (cb->entry->flags & XTOPT_PUT) + *(uint16_t *)XTOPT_MKPTR(cb) = cb->val.port; +} + static void (*const xtopt_subparse[])(struct xt_option_call *) = { [XTTYPE_UINT8] = xtopt_parse_int, [XTTYPE_UINT16] = xtopt_parse_int, @@ -367,6 +414,8 @@ static void (*const xtopt_subparse[])(struct xt_option_call *) = { [XTTYPE_MARKMASK32] = xtopt_parse_markmask, [XTTYPE_SYSLOGLEVEL] = xtopt_parse_sysloglevel, [XTTYPE_ONEHOST] = xtopt_parse_onehost, + [XTTYPE_PORT] = xtopt_parse_port, + [XTTYPE_PORT_NE] = xtopt_parse_port, }; static const size_t xtopt_psize[] = { @@ -381,6 +430,8 @@ static const size_t xtopt_psize[] = { [XTTYPE_STRING] = -1, [XTTYPE_SYSLOGLEVEL] = sizeof(uint8_t), [XTTYPE_ONEHOST] = sizeof(union nf_inet_addr), + [XTTYPE_PORT] = sizeof(uint16_t), + [XTTYPE_PORT_NE] = sizeof(uint16_t), }; /** |