From 33e262d4f80afcc464014f28012491bf0c5567ef Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Wed, 8 May 2013 15:01:12 +0200 Subject: libxtables: fix parsing of dotted network mask format After upgrade from iptables 1.4.8 to 1.4.18 netmask parsing got broken: -A foo -m policy --mode tunnel --dir in --tunnel-src 192.168.123.0/255.255.255.0 -j RETURN With iptables 1.4.18: iptables-restore v1.4.18: policy: bad value for option "--tunnel-src", or out of range (0-32) This was probably broken by the augmented parser. Reported-by: Thomas Jarosch Signed-off-by: Pablo Neira Ayuso --- libxtables/xtoptions.c | 38 +++++++++++++++++++++++++++++++++++--- 1 file changed, 35 insertions(+), 3 deletions(-) (limited to 'libxtables/xtoptions.c') diff --git a/libxtables/xtoptions.c b/libxtables/xtoptions.c index 452e0fef..78e9abd6 100644 --- a/libxtables/xtoptions.c +++ b/libxtables/xtoptions.c @@ -667,6 +667,33 @@ static void xtopt_parse_mport(struct xt_option_call *cb) free(lo_arg); } +static int xtopt_parse_mask(struct xt_option_call *cb) +{ + struct addrinfo hints = {.ai_family = afinfo->family, + .ai_flags = AI_NUMERICHOST }; + struct addrinfo *res; + int ret; + + ret = getaddrinfo(cb->arg, NULL, &hints, &res); + if (ret < 0) + return 0; + + memcpy(&cb->val.hmask, xtables_sa_host(res->ai_addr, res->ai_family), + xtables_sa_hostlen(res->ai_family)); + + switch(afinfo->family) { + case AF_INET: + cb->val.hlen = xtables_ipmask_to_cidr(&cb->val.hmask.in); + break; + case AF_INET6: + cb->val.hlen = xtables_ip6mask_to_cidr(&cb->val.hmask.in6); + break; + } + + freeaddrinfo(res); + return 1; +} + /** * Parse an integer and ensure it is within the address family's prefix length * limits. The result is stored in @cb->val.hlen. @@ -677,12 +704,17 @@ static void xtopt_parse_plen(struct xt_option_call *cb) unsigned int prefix_len = 128; /* happiness is a warm gcc */ cb->val.hlen = (afinfo->family == NFPROTO_IPV4) ? 32 : 128; - if (!xtables_strtoui(cb->arg, NULL, &prefix_len, 0, cb->val.hlen)) + if (!xtables_strtoui(cb->arg, NULL, &prefix_len, 0, cb->val.hlen)) { + /* Is this mask expressed in full format? e.g. 255.255.255.0 */ + if (xtopt_parse_mask(cb)) + return; + xt_params->exit_err(PARAMETER_PROBLEM, "%s: bad value for option \"--%s\", " - "or out of range (%u-%u).\n", + "neither a valid network mask " + "nor valid CIDR (%u-%u).\n", cb->ext_name, entry->name, 0, cb->val.hlen); - + } cb->val.hlen = prefix_len; } -- cgit v1.2.3