target/linux/generic/patches-3.7/604-netfilter_cisco_794x_iphone.patch

   1 diff --git a/include/linux/netfilter/nf_conntrack_sip.h b/include/linux/netfilter/nf_conntrack_sip.h
   2 index 387bdd0..ba7f571 100644
   3 --- a/include/linux/netfilter/nf_conntrack_sip.h
   4 +++ b/include/linux/netfilter/nf_conntrack_sip.h
   5 @@ -4,12 +4,15 @@
   6
   7  #include <net/netfilter/nf_conntrack_expect.h>
   8
   9 +#include <linux/types.h>
  10 +
  11  #define SIP_PORT       5060
  12  #define SIP_TIMEOUT    3600
  13
  14  struct nf_ct_sip_master {
  15         unsigned int    register_cseq;
  16         unsigned int    invite_cseq;
  17 +       __be16          forced_dport;
  18  };
  19
  20  enum sip_expectation_classes {
  21 diff --git a/net/netfilter/nf_nat_sip.c b/net/netfilter/nf_nat_sip.c
  22 index 16303c7..552e270 100644
  23 --- a/net/netfilter/nf_nat_sip.c
  24 +++ b/net/netfilter/nf_nat_sip.c
  25 @@ -95,6 +95,7 @@ static int map_addr(struct sk_buff *skb, unsigned int protoff,
  26         enum ip_conntrack_info ctinfo;
  27         struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
  28         enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
  29 +       struct nf_ct_sip_master *ct_sip_info = nfct_help_data(ct);
  30         char buffer[INET6_ADDRSTRLEN + sizeof("[]:nnnnn")];
  31         unsigned int buflen;
  32         union nf_inet_addr newaddr;
  33 @@ -107,7 +108,8 @@ static int map_addr(struct sk_buff *skb, unsigned int protoff,
  34         } else if (nf_inet_addr_cmp(&ct->tuplehash[dir].tuple.dst.u3, addr) &&
  35                    ct->tuplehash[dir].tuple.dst.u.udp.port == port) {
  36                 newaddr = ct->tuplehash[!dir].tuple.src.u3;
  37 -               newport = ct->tuplehash[!dir].tuple.src.u.udp.port;
  38 +               newport = ct_sip_info->forced_dport ? ct_sip_info->forced_dport :
  39 +                         ct->tuplehash[!dir].tuple.src.u.udp.port;
  40         } else
  41                 return 1;
  42
  43 @@ -144,6 +146,7 @@ static unsigned int nf_nat_sip(struct sk_buff *skb, unsigned int protoff,
  44         enum ip_conntrack_info ctinfo;
  45         struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
  46         enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
  47 +       struct nf_ct_sip_master *ct_sip_info = nfct_help_data(ct);
  48         unsigned int coff, matchoff, matchlen;
  49         enum sip_header_types hdr;
  50         union nf_inet_addr addr;
  51 @@ -258,6 +261,20 @@ next:
  52             !map_sip_addr(skb, protoff, dataoff, dptr, datalen, SIP_HDR_TO))
  53                 return NF_DROP;
  54
  55 +       /* Mangle destination port for Cisco phones, then fix up checksums */
  56 +       if (dir == IP_CT_DIR_REPLY && ct_sip_info->forced_dport) {
  57 +               struct udphdr *uh;
  58 +
  59 +               if (!skb_make_writable(skb, skb->len))
  60 +                       return NF_DROP;
  61 +
  62 +               uh = (void *)skb->data + protoff;
  63 +               uh->dest = ct_sip_info->forced_dport;
  64 +
  65 +               if (!nf_nat_mangle_udp_packet(skb, ct, ctinfo, protoff, 0, 0, NULL, 0))
  66 +                       return NF_DROP;
  67 +       }
  68 +
  69         return NF_ACCEPT;
  70  }
  71
  72 @@ -311,8 +328,10 @@ static unsigned int nf_nat_sip_expect(struct sk_buff *skb, unsigned int protoff,
  73         enum ip_conntrack_info ctinfo;
  74         struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
  75         enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
  76 +       struct nf_ct_sip_master *ct_sip_info = nfct_help_data(ct);
  77         union nf_inet_addr newaddr;
  78         u_int16_t port;
  79 +       __be16 srcport;
  80         char buffer[INET6_ADDRSTRLEN + sizeof("[]:nnnnn")];
  81         unsigned int buflen;
  82
  83 @@ -326,8 +345,9 @@ static unsigned int nf_nat_sip_expect(struct sk_buff *skb, unsigned int protoff,
  84         /* If the signalling port matches the connection's source port in the
  85          * original direction, try to use the destination port in the opposite
  86          * direction. */
  87 -       if (exp->tuple.dst.u.udp.port ==
  88 -           ct->tuplehash[dir].tuple.src.u.udp.port)
  89 +       srcport = ct_sip_info->forced_dport ? ct_sip_info->forced_dport :
  90 +                 ct->tuplehash[dir].tuple.src.u.udp.port;
  91 +       if (exp->tuple.dst.u.udp.port == srcport)
  92                 port = ntohs(ct->tuplehash[!dir].tuple.dst.u.udp.port);
  93         else
  94                 port = ntohs(exp->tuple.dst.u.udp.port);
  95 diff --git a/net/netfilter/nf_conntrack_sip.c b/net/netfilter/nf_conntrack_sip.c
  96 index df8f4f2..72a67bb 100644
  97 --- a/net/netfilter/nf_conntrack_sip.c
  98 +++ b/net/netfilter/nf_conntrack_sip.c
  99 @@ -1440,8 +1440,25 @@ static int process_sip_request(struct sk_buff *skb, unsigned int protoff,
 100  {
 101         enum ip_conntrack_info ctinfo;
 102         struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
 103 +       struct nf_ct_sip_master *ct_sip_info = nfct_help_data(ct);
 104 +       enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
 105         unsigned int matchoff, matchlen;
 106         unsigned int cseq, i;
 107 +       union nf_inet_addr addr;
 108 +       __be16 port;
 109 +
 110 +       /* Many Cisco IP phones use a high source port for SIP requests, but
 111 +        * listen for the response on port 5060.  If we are the local
 112 +        * router for one of these phones, save the port number from the
 113 +        * Via: header so that nf_nat_sip can redirect the responses to
 114 +        * the correct port.
 115 +        */
 116 +       if (ct_sip_parse_header_uri(ct, *dptr, NULL, *datalen,
 117 +                                   SIP_HDR_VIA_UDP, NULL, &matchoff,
 118 +                                   &matchlen, &addr, &port) > 0 &&
 119 +           port != ct->tuplehash[dir].tuple.src.u.udp.port &&
 120 +           nf_inet_addr_cmp(&addr, &ct->tuplehash[dir].tuple.src.u3))
 121 +               ct_sip_info->forced_dport = port;
 122
 123         for (i = 0; i < ARRAY_SIZE(sip_handlers); i++) {
 124                 const struct sip_handler *handler;