Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 1 | /* SIP extension for UDP NAT alteration. |
| 2 | * |
| 3 | * (C) 2005 by Christian Hentschel <chentschel@arnet.com.ar> |
| 4 | * based on RR's ip_nat_ftp.c and other modules. |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License version 2 as |
| 8 | * published by the Free Software Foundation. |
| 9 | */ |
| 10 | |
| 11 | #include <linux/module.h> |
| 12 | #include <linux/skbuff.h> |
| 13 | #include <linux/ip.h> |
Arnaldo Carvalho de Melo | c9bdd4b | 2007-03-12 20:09:15 -0300 | [diff] [blame] | 14 | #include <net/ip.h> |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 15 | #include <linux/udp.h> |
| 16 | |
| 17 | #include <net/netfilter/nf_nat.h> |
| 18 | #include <net/netfilter/nf_nat_helper.h> |
| 19 | #include <net/netfilter/nf_nat_rule.h> |
| 20 | #include <net/netfilter/nf_conntrack_helper.h> |
| 21 | #include <net/netfilter/nf_conntrack_expect.h> |
| 22 | #include <linux/netfilter/nf_conntrack_sip.h> |
| 23 | |
| 24 | MODULE_LICENSE("GPL"); |
| 25 | MODULE_AUTHOR("Christian Hentschel <chentschel@arnet.com.ar>"); |
| 26 | MODULE_DESCRIPTION("SIP NAT helper"); |
| 27 | MODULE_ALIAS("ip_nat_sip"); |
| 28 | |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 29 | struct addr_map { |
| 30 | struct { |
| 31 | char src[sizeof("nnn.nnn.nnn.nnn:nnnnn")]; |
| 32 | char dst[sizeof("nnn.nnn.nnn.nnn:nnnnn")]; |
| 33 | unsigned int srclen, srciplen; |
| 34 | unsigned int dstlen, dstiplen; |
| 35 | } addr[IP_CT_DIR_MAX]; |
| 36 | }; |
| 37 | |
Jan Engelhardt | 13f7d63 | 2008-01-31 04:50:25 -0800 | [diff] [blame] | 38 | static void addr_map_init(const struct nf_conn *ct, struct addr_map *map) |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 39 | { |
Jan Engelhardt | 13f7d63 | 2008-01-31 04:50:25 -0800 | [diff] [blame] | 40 | const struct nf_conntrack_tuple *t; |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 41 | enum ip_conntrack_dir dir; |
| 42 | unsigned int n; |
| 43 | |
| 44 | for (dir = 0; dir < IP_CT_DIR_MAX; dir++) { |
| 45 | t = &ct->tuplehash[dir].tuple; |
| 46 | |
| 47 | n = sprintf(map->addr[dir].src, "%u.%u.%u.%u", |
| 48 | NIPQUAD(t->src.u3.ip)); |
| 49 | map->addr[dir].srciplen = n; |
| 50 | n += sprintf(map->addr[dir].src + n, ":%u", |
| 51 | ntohs(t->src.u.udp.port)); |
| 52 | map->addr[dir].srclen = n; |
| 53 | |
| 54 | n = sprintf(map->addr[dir].dst, "%u.%u.%u.%u", |
| 55 | NIPQUAD(t->dst.u3.ip)); |
| 56 | map->addr[dir].dstiplen = n; |
| 57 | n += sprintf(map->addr[dir].dst + n, ":%u", |
| 58 | ntohs(t->dst.u.udp.port)); |
| 59 | map->addr[dir].dstlen = n; |
| 60 | } |
| 61 | } |
| 62 | |
Patrick McHardy | 2a6cfb2 | 2008-03-25 20:16:54 -0700 | [diff] [blame] | 63 | static unsigned int mangle_packet(struct sk_buff *skb, |
| 64 | const char **dptr, unsigned int *datalen, |
| 65 | unsigned int matchoff, unsigned int matchlen, |
| 66 | const char *buffer, unsigned int buflen) |
| 67 | { |
| 68 | enum ip_conntrack_info ctinfo; |
| 69 | struct nf_conn *ct = nf_ct_get(skb, &ctinfo); |
| 70 | |
| 71 | if (!nf_nat_mangle_udp_packet(skb, ct, ctinfo, matchoff, matchlen, |
| 72 | buffer, buflen)) |
| 73 | return 0; |
| 74 | |
| 75 | /* Reload data pointer and adjust datalen value */ |
| 76 | *dptr = skb->data + ip_hdrlen(skb) + sizeof(struct udphdr); |
| 77 | *datalen += buflen - matchlen; |
| 78 | return 1; |
| 79 | } |
| 80 | |
Patrick McHardy | ac36774 | 2008-03-25 20:18:40 -0700 | [diff] [blame] | 81 | static int map_addr(struct sk_buff *skb, |
| 82 | const char **dptr, unsigned int *datalen, |
| 83 | unsigned int matchoff, unsigned int matchlen, |
| 84 | struct addr_map *map) |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 85 | { |
Patrick McHardy | 212440a | 2008-03-25 20:17:13 -0700 | [diff] [blame] | 86 | enum ip_conntrack_info ctinfo; |
Patrick McHardy | ac36774 | 2008-03-25 20:18:40 -0700 | [diff] [blame] | 87 | struct nf_conn *ct __maybe_unused = nf_ct_get(skb, &ctinfo); |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 88 | enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo); |
Patrick McHardy | ac36774 | 2008-03-25 20:18:40 -0700 | [diff] [blame] | 89 | unsigned int addrlen; |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 90 | char *addr; |
| 91 | |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 92 | if ((matchlen == map->addr[dir].srciplen || |
| 93 | matchlen == map->addr[dir].srclen) && |
Patrick McHardy | 779382e | 2008-03-25 20:17:36 -0700 | [diff] [blame] | 94 | strncmp(*dptr + matchoff, map->addr[dir].src, matchlen) == 0) { |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 95 | addr = map->addr[!dir].dst; |
| 96 | addrlen = map->addr[!dir].dstlen; |
| 97 | } else if ((matchlen == map->addr[dir].dstiplen || |
| 98 | matchlen == map->addr[dir].dstlen) && |
Patrick McHardy | 779382e | 2008-03-25 20:17:36 -0700 | [diff] [blame] | 99 | strncmp(*dptr + matchoff, map->addr[dir].dst, matchlen) == 0) { |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 100 | addr = map->addr[!dir].src; |
| 101 | addrlen = map->addr[!dir].srclen; |
| 102 | } else |
| 103 | return 1; |
| 104 | |
Patrick McHardy | 2a6cfb2 | 2008-03-25 20:16:54 -0700 | [diff] [blame] | 105 | return mangle_packet(skb, dptr, datalen, matchoff, matchlen, |
| 106 | addr, addrlen); |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 107 | } |
| 108 | |
Patrick McHardy | ac36774 | 2008-03-25 20:18:40 -0700 | [diff] [blame] | 109 | static int map_sip_addr(struct sk_buff *skb, |
| 110 | const char **dptr, unsigned int *datalen, |
Patrick McHardy | ea45f12 | 2008-03-25 20:18:57 -0700 | [diff] [blame^] | 111 | enum sip_header_types type, struct addr_map *map) |
Patrick McHardy | ac36774 | 2008-03-25 20:18:40 -0700 | [diff] [blame] | 112 | { |
| 113 | enum ip_conntrack_info ctinfo; |
| 114 | struct nf_conn *ct = nf_ct_get(skb, &ctinfo); |
| 115 | unsigned int matchlen, matchoff; |
| 116 | |
Patrick McHardy | ea45f12 | 2008-03-25 20:18:57 -0700 | [diff] [blame^] | 117 | if (ct_sip_get_header(ct, *dptr, 0, *datalen, type, |
| 118 | &matchoff, &matchlen) <= 0) |
Patrick McHardy | ac36774 | 2008-03-25 20:18:40 -0700 | [diff] [blame] | 119 | return 1; |
| 120 | return map_addr(skb, dptr, datalen, matchoff, matchlen, map); |
| 121 | } |
| 122 | |
Herbert Xu | 3db05fe | 2007-10-15 00:53:15 -0700 | [diff] [blame] | 123 | static unsigned int ip_nat_sip(struct sk_buff *skb, |
Patrick McHardy | 2a6cfb2 | 2008-03-25 20:16:54 -0700 | [diff] [blame] | 124 | const char **dptr, unsigned int *datalen) |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 125 | { |
Patrick McHardy | 212440a | 2008-03-25 20:17:13 -0700 | [diff] [blame] | 126 | enum ip_conntrack_info ctinfo; |
| 127 | struct nf_conn *ct = nf_ct_get(skb, &ctinfo); |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 128 | struct addr_map map; |
Patrick McHardy | ac36774 | 2008-03-25 20:18:40 -0700 | [diff] [blame] | 129 | unsigned int matchoff, matchlen; |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 130 | |
Patrick McHardy | 779382e | 2008-03-25 20:17:36 -0700 | [diff] [blame] | 131 | if (*datalen < strlen("SIP/2.0")) |
Patrick McHardy | 45241a7 | 2007-08-14 13:14:58 -0700 | [diff] [blame] | 132 | return NF_ACCEPT; |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 133 | |
| 134 | addr_map_init(ct, &map); |
| 135 | |
| 136 | /* Basic rules: requests and responses. */ |
Patrick McHardy | 779382e | 2008-03-25 20:17:36 -0700 | [diff] [blame] | 137 | if (strnicmp(*dptr, "SIP/2.0", strlen("SIP/2.0")) != 0) { |
Patrick McHardy | ac36774 | 2008-03-25 20:18:40 -0700 | [diff] [blame] | 138 | if (ct_sip_parse_request(ct, *dptr, *datalen, |
| 139 | &matchoff, &matchlen) > 0 && |
| 140 | !map_addr(skb, dptr, datalen, matchoff, matchlen, &map)) |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 141 | return NF_DROP; |
| 142 | } |
| 143 | |
Patrick McHardy | ea45f12 | 2008-03-25 20:18:57 -0700 | [diff] [blame^] | 144 | if (!map_sip_addr(skb, dptr, datalen, SIP_HDR_FROM, &map) || |
| 145 | !map_sip_addr(skb, dptr, datalen, SIP_HDR_TO, &map) || |
| 146 | !map_sip_addr(skb, dptr, datalen, SIP_HDR_VIA, &map) || |
| 147 | !map_sip_addr(skb, dptr, datalen, SIP_HDR_CONTACT, &map)) |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 148 | return NF_DROP; |
| 149 | return NF_ACCEPT; |
| 150 | } |
| 151 | |
Herbert Xu | 3db05fe | 2007-10-15 00:53:15 -0700 | [diff] [blame] | 152 | static int mangle_content_len(struct sk_buff *skb, |
Patrick McHardy | 2a6cfb2 | 2008-03-25 20:16:54 -0700 | [diff] [blame] | 153 | const char **dptr, unsigned int *datalen) |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 154 | { |
Patrick McHardy | 212440a | 2008-03-25 20:17:13 -0700 | [diff] [blame] | 155 | enum ip_conntrack_info ctinfo; |
| 156 | struct nf_conn *ct = nf_ct_get(skb, &ctinfo); |
Patrick McHardy | 2a6cfb2 | 2008-03-25 20:16:54 -0700 | [diff] [blame] | 157 | unsigned int matchoff, matchlen; |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 158 | char buffer[sizeof("65536")]; |
Patrick McHardy | 3e9b4600b | 2008-03-25 20:17:55 -0700 | [diff] [blame] | 159 | int buflen, c_len; |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 160 | |
Joe Perches | e00ccd4 | 2007-12-20 14:05:03 -0800 | [diff] [blame] | 161 | /* Get actual SDP length */ |
Patrick McHardy | 3e9b4600b | 2008-03-25 20:17:55 -0700 | [diff] [blame] | 162 | if (ct_sip_get_sdp_header(ct, *dptr, 0, *datalen, |
| 163 | SDP_HDR_VERSION, SDP_HDR_UNSPEC, |
| 164 | &matchoff, &matchlen) <= 0) |
| 165 | return 0; |
| 166 | c_len = *datalen - matchoff + strlen("v="); |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 167 | |
Patrick McHardy | 3e9b4600b | 2008-03-25 20:17:55 -0700 | [diff] [blame] | 168 | /* Now, update SDP length */ |
Patrick McHardy | ea45f12 | 2008-03-25 20:18:57 -0700 | [diff] [blame^] | 169 | if (ct_sip_get_header(ct, *dptr, 0, *datalen, SIP_HDR_CONTENT_LENGTH, |
| 170 | &matchoff, &matchlen) <= 0) |
Patrick McHardy | 3e9b4600b | 2008-03-25 20:17:55 -0700 | [diff] [blame] | 171 | return 0; |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 172 | |
Patrick McHardy | 3e9b4600b | 2008-03-25 20:17:55 -0700 | [diff] [blame] | 173 | buflen = sprintf(buffer, "%u", c_len); |
| 174 | return mangle_packet(skb, dptr, datalen, matchoff, matchlen, |
| 175 | buffer, buflen); |
| 176 | } |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 177 | |
Patrick McHardy | 3e9b4600b | 2008-03-25 20:17:55 -0700 | [diff] [blame] | 178 | static unsigned mangle_sdp_packet(struct sk_buff *skb, |
| 179 | const char **dptr, unsigned int *datalen, |
| 180 | enum sdp_header_types type, |
| 181 | char *buffer, int buflen) |
| 182 | { |
| 183 | enum ip_conntrack_info ctinfo; |
| 184 | struct nf_conn *ct = nf_ct_get(skb, &ctinfo); |
| 185 | unsigned int matchlen, matchoff; |
| 186 | |
| 187 | if (ct_sip_get_sdp_header(ct, *dptr, 0, *datalen, type, SDP_HDR_UNSPEC, |
| 188 | &matchoff, &matchlen) <= 0) |
| 189 | return 0; |
| 190 | return mangle_packet(skb, dptr, datalen, matchoff, matchlen, |
| 191 | buffer, buflen); |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 192 | } |
| 193 | |
Herbert Xu | 3db05fe | 2007-10-15 00:53:15 -0700 | [diff] [blame] | 194 | static unsigned int mangle_sdp(struct sk_buff *skb, |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 195 | enum ip_conntrack_info ctinfo, |
| 196 | struct nf_conn *ct, |
| 197 | __be32 newip, u_int16_t port, |
Patrick McHardy | 2a6cfb2 | 2008-03-25 20:16:54 -0700 | [diff] [blame] | 198 | const char **dptr, unsigned int *datalen) |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 199 | { |
| 200 | char buffer[sizeof("nnn.nnn.nnn.nnn")]; |
Patrick McHardy | 2a6cfb2 | 2008-03-25 20:16:54 -0700 | [diff] [blame] | 201 | unsigned int bufflen; |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 202 | |
| 203 | /* Mangle owner and contact info. */ |
| 204 | bufflen = sprintf(buffer, "%u.%u.%u.%u", NIPQUAD(newip)); |
Patrick McHardy | 3e9b4600b | 2008-03-25 20:17:55 -0700 | [diff] [blame] | 205 | if (!mangle_sdp_packet(skb, dptr, datalen, SDP_HDR_OWNER_IP4, |
| 206 | buffer, bufflen)) |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 207 | return 0; |
| 208 | |
Patrick McHardy | 3e9b4600b | 2008-03-25 20:17:55 -0700 | [diff] [blame] | 209 | if (!mangle_sdp_packet(skb, dptr, datalen, SDP_HDR_CONNECTION_IP4, |
| 210 | buffer, bufflen)) |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 211 | return 0; |
| 212 | |
| 213 | /* Mangle media port. */ |
| 214 | bufflen = sprintf(buffer, "%u", port); |
Patrick McHardy | 3e9b4600b | 2008-03-25 20:17:55 -0700 | [diff] [blame] | 215 | if (!mangle_sdp_packet(skb, dptr, datalen, SDP_HDR_MEDIA, |
| 216 | buffer, bufflen)) |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 217 | return 0; |
| 218 | |
Patrick McHardy | 212440a | 2008-03-25 20:17:13 -0700 | [diff] [blame] | 219 | return mangle_content_len(skb, dptr, datalen); |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 220 | } |
| 221 | |
Herbert Xu | cfd6c38 | 2007-05-03 03:35:31 -0700 | [diff] [blame] | 222 | static void ip_nat_sdp_expect(struct nf_conn *ct, |
| 223 | struct nf_conntrack_expect *exp) |
| 224 | { |
| 225 | struct nf_nat_range range; |
| 226 | |
| 227 | /* This must be a fresh one. */ |
| 228 | BUG_ON(ct->status & IPS_NAT_DONE_MASK); |
| 229 | |
Herbert Xu | cfd6c38 | 2007-05-03 03:35:31 -0700 | [diff] [blame] | 230 | /* For DST manip, map port here to where it's expected. */ |
| 231 | range.flags = (IP_NAT_RANGE_MAP_IPS | IP_NAT_RANGE_PROTO_SPECIFIED); |
| 232 | range.min = range.max = exp->saved_proto; |
| 233 | range.min_ip = range.max_ip = exp->saved_ip; |
Patrick McHardy | cc01dcb | 2007-12-17 22:38:20 -0800 | [diff] [blame] | 234 | nf_nat_setup_info(ct, &range, IP_NAT_MANIP_DST); |
Patrick McHardy | 3d24412 | 2008-03-25 20:09:51 -0700 | [diff] [blame] | 235 | |
| 236 | /* Change src to where master sends to */ |
| 237 | range.flags = IP_NAT_RANGE_MAP_IPS; |
| 238 | range.min_ip = range.max_ip |
| 239 | = ct->master->tuplehash[!exp->dir].tuple.dst.u3.ip; |
| 240 | nf_nat_setup_info(ct, &range, IP_NAT_MANIP_SRC); |
Herbert Xu | cfd6c38 | 2007-05-03 03:35:31 -0700 | [diff] [blame] | 241 | } |
| 242 | |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 243 | /* So, this packet has hit the connection tracking matching code. |
| 244 | Mangle it, and change the expectation to match the new version. */ |
Herbert Xu | 3db05fe | 2007-10-15 00:53:15 -0700 | [diff] [blame] | 245 | static unsigned int ip_nat_sdp(struct sk_buff *skb, |
Patrick McHardy | 212440a | 2008-03-25 20:17:13 -0700 | [diff] [blame] | 246 | const char **dptr, unsigned int *datalen, |
| 247 | struct nf_conntrack_expect *exp) |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 248 | { |
Patrick McHardy | 212440a | 2008-03-25 20:17:13 -0700 | [diff] [blame] | 249 | enum ip_conntrack_info ctinfo; |
| 250 | struct nf_conn *ct = nf_ct_get(skb, &ctinfo); |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 251 | enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo); |
| 252 | __be32 newip; |
| 253 | u_int16_t port; |
| 254 | |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 255 | /* Connection will come from reply */ |
Jerome Borsboom | f4a607b | 2007-07-07 22:19:48 -0700 | [diff] [blame] | 256 | if (ct->tuplehash[dir].tuple.src.u3.ip == |
| 257 | ct->tuplehash[!dir].tuple.dst.u3.ip) |
| 258 | newip = exp->tuple.dst.u3.ip; |
| 259 | else |
| 260 | newip = ct->tuplehash[!dir].tuple.dst.u3.ip; |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 261 | |
Herbert Xu | cfd6c38 | 2007-05-03 03:35:31 -0700 | [diff] [blame] | 262 | exp->saved_ip = exp->tuple.dst.u3.ip; |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 263 | exp->tuple.dst.u3.ip = newip; |
| 264 | exp->saved_proto.udp.port = exp->tuple.dst.u.udp.port; |
| 265 | exp->dir = !dir; |
| 266 | |
| 267 | /* When you see the packet, we need to NAT it the same as the |
| 268 | this one. */ |
Herbert Xu | cfd6c38 | 2007-05-03 03:35:31 -0700 | [diff] [blame] | 269 | exp->expectfn = ip_nat_sdp_expect; |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 270 | |
| 271 | /* Try to get same port: if not, try to change it. */ |
| 272 | for (port = ntohs(exp->saved_proto.udp.port); port != 0; port++) { |
| 273 | exp->tuple.dst.u.udp.port = htons(port); |
Patrick McHardy | 6823645 | 2007-07-07 22:30:49 -0700 | [diff] [blame] | 274 | if (nf_ct_expect_related(exp) == 0) |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 275 | break; |
| 276 | } |
| 277 | |
| 278 | if (port == 0) |
| 279 | return NF_DROP; |
| 280 | |
Patrick McHardy | 2a6cfb2 | 2008-03-25 20:16:54 -0700 | [diff] [blame] | 281 | if (!mangle_sdp(skb, ctinfo, ct, newip, port, dptr, datalen)) { |
Patrick McHardy | 6823645 | 2007-07-07 22:30:49 -0700 | [diff] [blame] | 282 | nf_ct_unexpect_related(exp); |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 283 | return NF_DROP; |
| 284 | } |
| 285 | return NF_ACCEPT; |
| 286 | } |
| 287 | |
| 288 | static void __exit nf_nat_sip_fini(void) |
| 289 | { |
| 290 | rcu_assign_pointer(nf_nat_sip_hook, NULL); |
| 291 | rcu_assign_pointer(nf_nat_sdp_hook, NULL); |
| 292 | synchronize_rcu(); |
| 293 | } |
| 294 | |
| 295 | static int __init nf_nat_sip_init(void) |
| 296 | { |
Patrick McHardy | d1332e0 | 2007-11-05 20:43:30 -0800 | [diff] [blame] | 297 | BUG_ON(nf_nat_sip_hook != NULL); |
| 298 | BUG_ON(nf_nat_sdp_hook != NULL); |
Patrick McHardy | 9fafcd7 | 2006-12-02 22:09:57 -0800 | [diff] [blame] | 299 | rcu_assign_pointer(nf_nat_sip_hook, ip_nat_sip); |
| 300 | rcu_assign_pointer(nf_nat_sdp_hook, ip_nat_sdp); |
| 301 | return 0; |
| 302 | } |
| 303 | |
| 304 | module_init(nf_nat_sip_init); |
| 305 | module_exit(nf_nat_sip_fini); |