diff options
| -rw-r--r-- | include/linux/netfilter/nf_conntrack_sip.h | 3 | ||||
| -rw-r--r-- | net/netfilter/nf_conntrack_sip.c | 17 | ||||
| -rw-r--r-- | net/netfilter/nf_nat_sip.c | 27 |
3 files changed, 44 insertions, 3 deletions
diff --git a/include/linux/netfilter/nf_conntrack_sip.h b/include/linux/netfilter/nf_conntrack_sip.h index 387bdd02945d..ba7f571a2b1c 100644 --- a/include/linux/netfilter/nf_conntrack_sip.h +++ b/include/linux/netfilter/nf_conntrack_sip.h @@ -4,12 +4,15 @@ #include <net/netfilter/nf_conntrack_expect.h> +#include <linux/types.h> + #define SIP_PORT 5060 #define SIP_TIMEOUT 3600 struct nf_ct_sip_master { unsigned int register_cseq; unsigned int invite_cseq; + __be16 forced_dport; }; enum sip_expectation_classes { diff --git a/net/netfilter/nf_conntrack_sip.c b/net/netfilter/nf_conntrack_sip.c index df8f4f284481..72a67bbe3518 100644 --- a/net/netfilter/nf_conntrack_sip.c +++ b/net/netfilter/nf_conntrack_sip.c @@ -1440,8 +1440,25 @@ static int process_sip_request(struct sk_buff *skb, unsigned int protoff, { enum ip_conntrack_info ctinfo; struct nf_conn *ct = nf_ct_get(skb, &ctinfo); + struct nf_ct_sip_master *ct_sip_info = nfct_help_data(ct); + enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo); unsigned int matchoff, matchlen; unsigned int cseq, i; + union nf_inet_addr addr; + __be16 port; + + /* Many Cisco IP phones use a high source port for SIP requests, but + * listen for the response on port 5060. If we are the local + * router for one of these phones, save the port number from the + * Via: header so that nf_nat_sip can redirect the responses to + * the correct port. + */ + if (ct_sip_parse_header_uri(ct, *dptr, NULL, *datalen, + SIP_HDR_VIA_UDP, NULL, &matchoff, + &matchlen, &addr, &port) > 0 && + port != ct->tuplehash[dir].tuple.src.u.udp.port && + nf_inet_addr_cmp(&addr, &ct->tuplehash[dir].tuple.src.u3)) + ct_sip_info->forced_dport = port; for (i = 0; i < ARRAY_SIZE(sip_handlers); i++) { const struct sip_handler *handler; diff --git a/net/netfilter/nf_nat_sip.c b/net/netfilter/nf_nat_sip.c index 16303c752213..5951146e7688 100644 --- a/net/netfilter/nf_nat_sip.c +++ b/net/netfilter/nf_nat_sip.c @@ -95,6 +95,7 @@ static int map_addr(struct sk_buff *skb, unsigned int protoff, enum ip_conntrack_info ctinfo; struct nf_conn *ct = nf_ct_get(skb, &ctinfo); enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo); + struct nf_ct_sip_master *ct_sip_info = nfct_help_data(ct); char buffer[INET6_ADDRSTRLEN + sizeof("[]:nnnnn")]; unsigned int buflen; union nf_inet_addr newaddr; @@ -107,7 +108,8 @@ static int map_addr(struct sk_buff *skb, unsigned int protoff, } else if (nf_inet_addr_cmp(&ct->tuplehash[dir].tuple.dst.u3, addr) && ct->tuplehash[dir].tuple.dst.u.udp.port == port) { newaddr = ct->tuplehash[!dir].tuple.src.u3; - newport = ct->tuplehash[!dir].tuple.src.u.udp.port; + newport = ct_sip_info->forced_dport ? : + ct->tuplehash[!dir].tuple.src.u.udp.port; } else return 1; @@ -144,6 +146,7 @@ static unsigned int nf_nat_sip(struct sk_buff *skb, unsigned int protoff, enum ip_conntrack_info ctinfo; struct nf_conn *ct = nf_ct_get(skb, &ctinfo); enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo); + struct nf_ct_sip_master *ct_sip_info = nfct_help_data(ct); unsigned int coff, matchoff, matchlen; enum sip_header_types hdr; union nf_inet_addr addr; @@ -258,6 +261,21 @@ next: !map_sip_addr(skb, protoff, dataoff, dptr, datalen, SIP_HDR_TO)) return NF_DROP; + /* Mangle destination port for Cisco phones, then fix up checksums */ + if (dir == IP_CT_DIR_REPLY && ct_sip_info->forced_dport) { + struct udphdr *uh; + + if (!skb_make_writable(skb, skb->len)) + return NF_DROP; + + uh = (void *)skb->data + protoff; + uh->dest = ct_sip_info->forced_dport; + + if (!nf_nat_mangle_udp_packet(skb, ct, ctinfo, protoff, + 0, 0, NULL, 0)) + return NF_DROP; + } + return NF_ACCEPT; } @@ -311,8 +329,10 @@ static unsigned int nf_nat_sip_expect(struct sk_buff *skb, unsigned int protoff, enum ip_conntrack_info ctinfo; struct nf_conn *ct = nf_ct_get(skb, &ctinfo); enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo); + struct nf_ct_sip_master *ct_sip_info = nfct_help_data(ct); union nf_inet_addr newaddr; u_int16_t port; + __be16 srcport; char buffer[INET6_ADDRSTRLEN + sizeof("[]:nnnnn")]; unsigned int buflen; @@ -326,8 +346,9 @@ static unsigned int nf_nat_sip_expect(struct sk_buff *skb, unsigned int protoff, /* If the signalling port matches the connection's source port in the * original direction, try to use the destination port in the opposite * direction. */ - if (exp->tuple.dst.u.udp.port == - ct->tuplehash[dir].tuple.src.u.udp.port) + srcport = ct_sip_info->forced_dport ? : + ct->tuplehash[dir].tuple.src.u.udp.port; + if (exp->tuple.dst.u.udp.port == srcport) port = ntohs(ct->tuplehash[!dir].tuple.dst.u.udp.port); else port = ntohs(exp->tuple.dst.u.udp.port); |