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

   1 --- a/include/linux/netfilter/nf_conntrack_sip.h
   2 +++ b/include/linux/netfilter/nf_conntrack_sip.h
   3 @@ -4,12 +4,15 @@
   4
   5  #include <net/netfilter/nf_conntrack_expect.h>
   6
   7 +#include <linux/types.h>
   8 +
   9  #define SIP_PORT       5060
  10  #define SIP_TIMEOUT    3600
  11
  12  struct nf_ct_sip_master {
  13         unsigned int    register_cseq;
  14         unsigned int    invite_cseq;
  15 +       __be16          forced_dport;
  16  };
  17
  18  enum sip_expectation_classes {
  19 --- a/net/netfilter/nf_nat_sip.c
  20 +++ b/net/netfilter/nf_nat_sip.c
  21 @@ -95,11 +95,14 @@ static int map_addr(struct sk_buff *skb,
  22         enum ip_conntrack_info ctinfo;
  23         struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
  24         enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
  25 +       struct nf_ct_sip_master *ct_sip_info;
  26         char buffer[INET6_ADDRSTRLEN + sizeof("[]:nnnnn")];
  27         unsigned int buflen;
  28         union nf_inet_addr newaddr;
  29         __be16 newport;
  30
  31 +       ct_sip_info = nfct_help_data(ct->master);
  32 +
  33         if (nf_inet_addr_cmp(&ct->tuplehash[dir].tuple.src.u3, addr) &&
  34             ct->tuplehash[dir].tuple.src.u.udp.port == port) {
  35                 newaddr = ct->tuplehash[!dir].tuple.dst.u3;
  36 @@ -107,7 +110,8 @@ static int map_addr(struct sk_buff *skb,
  37         } else if (nf_inet_addr_cmp(&ct->tuplehash[dir].tuple.dst.u3, addr) &&
  38                    ct->tuplehash[dir].tuple.dst.u.udp.port == port) {
  39                 newaddr = ct->tuplehash[!dir].tuple.src.u3;
  40 -               newport = ct->tuplehash[!dir].tuple.src.u.udp.port;
  41 +               newport = ct_sip_info->forced_dport ? :
  42 +                         ct->tuplehash[!dir].tuple.src.u.udp.port;
  43         } else
  44                 return 1;
  45
  46 @@ -144,6 +148,7 @@ static unsigned int nf_nat_sip(struct sk
  47         enum ip_conntrack_info ctinfo;
  48         struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
  49         enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
  50 +       struct nf_conn_help *help = nfct_help(ct);
  51         unsigned int coff, matchoff, matchlen;
  52         enum sip_header_types hdr;
  53         union nf_inet_addr addr;
  54 @@ -258,6 +263,22 @@ next:
  55             !map_sip_addr(skb, protoff, dataoff, dptr, datalen, SIP_HDR_TO))
  56                 return NF_DROP;
  57
  58 +       struct nf_ct_sip_master *ct_sip_info = nfct_help_data(ct->master);
  59 +
  60 +       /* Mangle destination port for Cisco phones, then fix up checksums */
  61 +       if (dir == IP_CT_DIR_REPLY && ct_sip_info->forced_dport) {
  62 +               struct udphdr *uh;
  63 +
  64 +               if (!skb_make_writable(skb, skb->len))
  65 +                       return NF_DROP;
  66 +
  67 +               uh = (struct udphdr *)(skb->data + ip_hdrlen(skb));
  68 +               uh->dest = ct_sip_info->forced_dport;
  69 +
  70 +               if (!nf_nat_mangle_udp_packet(skb, ct, ctinfo, 0, 0, NULL, 0))
  71 +                       return NF_DROP;
  72 +       }
  73 +
  74         return NF_ACCEPT;
  75  }
  76
  77 @@ -311,10 +332,13 @@ static unsigned int nf_nat_sip_expect(st
  78         enum ip_conntrack_info ctinfo;
  79         struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
  80         enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
  81 +       struct nf_conn_help *help = nfct_help(ct);
  82         union nf_inet_addr newaddr;
  83         u_int16_t port;
  84 +       __be16 srcport;
  85         char buffer[INET6_ADDRSTRLEN + sizeof("[]:nnnnn")];
  86         unsigned int buflen;
  87 +       struct nf_ct_sip_master *ct_sip_info = nfct_help_data(ct->master);
  88
  89         /* Connection will come from reply */
  90         if (nf_inet_addr_cmp(&ct->tuplehash[dir].tuple.src.u3,
  91 @@ -326,8 +350,9 @@ static unsigned int nf_nat_sip_expect(st
  92         /* If the signalling port matches the connection's source port in the
  93          * original direction, try to use the destination port in the opposite
  94          * direction. */
  95 -       if (exp->tuple.dst.u.udp.port ==
  96 -           ct->tuplehash[dir].tuple.src.u.udp.port)
  97 +       srcport = ct_sip_info->forced_dport ? :
  98 +                 ct->tuplehash[dir].tuple.src.u.udp.port;
  99 +       if (exp->tuple.dst.u.udp.port == srcport)
 100                 port = ntohs(ct->tuplehash[!dir].tuple.dst.u.udp.port);
 101         else
 102                 port = ntohs(exp->tuple.dst.u.udp.port);
 103 --- a/net/netfilter/nf_conntrack_sip.c
 104 +++ b/net/netfilter/nf_conntrack_sip.c
 105 @@ -1440,8 +1440,26 @@ static int process_sip_request(struct sk
 106  {
 107         enum ip_conntrack_info ctinfo;
 108         struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
 109 +       struct nf_conn_help *help = nfct_help(ct);
 110 +       enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
 111         unsigned int matchoff, matchlen;
 112         unsigned int cseq, i;
 113 +       union nf_inet_addr addr;
 114 +       __be16 port;
 115 +       struct nf_ct_sip_master *ct_sip_info = nfct_help_data(ct->master);
 116 +
 117 +       /* Many Cisco IP phones use a high source port for SIP requests, but
 118 +        * listen for the response on port 5060.  If we are the local
 119 +        * router for one of these phones, save the port number from the
 120 +        * Via: header so that nf_nat_sip can redirect the responses to
 121 +        * the correct port.
 122 +        */
 123 +       if (ct_sip_parse_header_uri(ct, *dptr, NULL, *datalen,
 124 +                                   SIP_HDR_VIA_UDP, NULL, &matchoff,
 125 +                                   &matchlen, &addr, &port) > 0 &&
 126 +           port != ct->tuplehash[dir].tuple.src.u.udp.port &&
 127 +           nf_inet_addr_cmp(&addr, &ct->tuplehash[dir].tuple.src.u3))
 128 +               ct_sip_info->forced_dport = port;
 129
 130         for (i = 0; i < ARRAY_SIZE(sip_handlers); i++) {
 131                 const struct sip_handler *handler;