From 051966c0c644a1c96092d4206e00704ade813c9a Mon Sep 17 00:00:00 2001 From: Patrick McHardy Date: Sun, 26 Aug 2012 19:14:04 +0200 Subject: netfilter: nf_nat: add protoff argument to packet mangling functions For mangling IPv6 packets the protocol header offset needs to be known by the NAT packet mangling functions. Add a so far unused protoff argument and convert the conntrack and NAT helpers to use it in preparation of IPv6 NAT. Signed-off-by: Patrick McHardy --- net/ipv4/netfilter/nf_nat_sip.c | 96 +++++++++++++++++++++++------------------ 1 file changed, 54 insertions(+), 42 deletions(-) (limited to 'net/ipv4/netfilter/nf_nat_sip.c') diff --git a/net/ipv4/netfilter/nf_nat_sip.c b/net/ipv4/netfilter/nf_nat_sip.c index 4ad9cf173992..df626af8413c 100644 --- a/net/ipv4/netfilter/nf_nat_sip.c +++ b/net/ipv4/netfilter/nf_nat_sip.c @@ -30,7 +30,8 @@ MODULE_DESCRIPTION("SIP NAT helper"); MODULE_ALIAS("ip_nat_sip"); -static unsigned int mangle_packet(struct sk_buff *skb, unsigned int dataoff, +static unsigned int mangle_packet(struct sk_buff *skb, unsigned int protoff, + unsigned int dataoff, const char **dptr, unsigned int *datalen, unsigned int matchoff, unsigned int matchlen, const char *buffer, unsigned int buflen) @@ -46,7 +47,7 @@ static unsigned int mangle_packet(struct sk_buff *skb, unsigned int dataoff, matchoff += dataoff - baseoff; if (!__nf_nat_mangle_tcp_packet(skb, ct, ctinfo, - matchoff, matchlen, + protoff, matchoff, matchlen, buffer, buflen, false)) return 0; } else { @@ -54,7 +55,7 @@ static unsigned int mangle_packet(struct sk_buff *skb, unsigned int dataoff, matchoff += dataoff - baseoff; if (!nf_nat_mangle_udp_packet(skb, ct, ctinfo, - matchoff, matchlen, + protoff, matchoff, matchlen, buffer, buflen)) return 0; } @@ -65,7 +66,8 @@ static unsigned int mangle_packet(struct sk_buff *skb, unsigned int dataoff, return 1; } -static int map_addr(struct sk_buff *skb, unsigned int dataoff, +static int map_addr(struct sk_buff *skb, unsigned int protoff, + unsigned int dataoff, const char **dptr, unsigned int *datalen, unsigned int matchoff, unsigned int matchlen, union nf_inet_addr *addr, __be16 port) @@ -94,11 +96,12 @@ static int map_addr(struct sk_buff *skb, unsigned int dataoff, buflen = sprintf(buffer, "%pI4:%u", &newaddr, ntohs(newport)); - return mangle_packet(skb, dataoff, dptr, datalen, matchoff, matchlen, - buffer, buflen); + return mangle_packet(skb, protoff, dataoff, dptr, datalen, + matchoff, matchlen, buffer, buflen); } -static int map_sip_addr(struct sk_buff *skb, unsigned int dataoff, +static int map_sip_addr(struct sk_buff *skb, unsigned int protoff, + unsigned int dataoff, const char **dptr, unsigned int *datalen, enum sip_header_types type) { @@ -111,11 +114,12 @@ static int map_sip_addr(struct sk_buff *skb, unsigned int dataoff, if (ct_sip_parse_header_uri(ct, *dptr, NULL, *datalen, type, NULL, &matchoff, &matchlen, &addr, &port) <= 0) return 1; - return map_addr(skb, dataoff, dptr, datalen, matchoff, matchlen, - &addr, port); + return map_addr(skb, protoff, dataoff, dptr, datalen, + matchoff, matchlen, &addr, port); } -static unsigned int ip_nat_sip(struct sk_buff *skb, unsigned int dataoff, +static unsigned int ip_nat_sip(struct sk_buff *skb, unsigned int protoff, + unsigned int dataoff, const char **dptr, unsigned int *datalen) { enum ip_conntrack_info ctinfo; @@ -132,8 +136,8 @@ static unsigned int ip_nat_sip(struct sk_buff *skb, unsigned int dataoff, if (ct_sip_parse_request(ct, *dptr, *datalen, &matchoff, &matchlen, &addr, &port) > 0 && - !map_addr(skb, dataoff, dptr, datalen, matchoff, matchlen, - &addr, port)) + !map_addr(skb, protoff, dataoff, dptr, datalen, + matchoff, matchlen, &addr, port)) return NF_DROP; request = 1; } else @@ -164,8 +168,8 @@ static unsigned int ip_nat_sip(struct sk_buff *skb, unsigned int dataoff, } olen = *datalen; - if (!map_addr(skb, dataoff, dptr, datalen, matchoff, matchlen, - &addr, port)) + if (!map_addr(skb, protoff, dataoff, dptr, datalen, + matchoff, matchlen, &addr, port)) return NF_DROP; matchend = matchoff + matchlen + *datalen - olen; @@ -179,7 +183,7 @@ static unsigned int ip_nat_sip(struct sk_buff *skb, unsigned int dataoff, addr.ip != ct->tuplehash[!dir].tuple.dst.u3.ip) { buflen = sprintf(buffer, "%pI4", &ct->tuplehash[!dir].tuple.dst.u3.ip); - if (!mangle_packet(skb, dataoff, dptr, datalen, + if (!mangle_packet(skb, protoff, dataoff, dptr, datalen, poff, plen, buffer, buflen)) return NF_DROP; } @@ -193,7 +197,7 @@ static unsigned int ip_nat_sip(struct sk_buff *skb, unsigned int dataoff, addr.ip != ct->tuplehash[!dir].tuple.src.u3.ip) { buflen = sprintf(buffer, "%pI4", &ct->tuplehash[!dir].tuple.src.u3.ip); - if (!mangle_packet(skb, dataoff, dptr, datalen, + if (!mangle_packet(skb, protoff, dataoff, dptr, datalen, poff, plen, buffer, buflen)) return NF_DROP; } @@ -207,7 +211,7 @@ static unsigned int ip_nat_sip(struct sk_buff *skb, unsigned int dataoff, htons(n) != ct->tuplehash[!dir].tuple.src.u.udp.port) { __be16 p = ct->tuplehash[!dir].tuple.src.u.udp.port; buflen = sprintf(buffer, "%u", ntohs(p)); - if (!mangle_packet(skb, dataoff, dptr, datalen, + if (!mangle_packet(skb, protoff, dataoff, dptr, datalen, poff, plen, buffer, buflen)) return NF_DROP; } @@ -221,13 +225,14 @@ next: SIP_HDR_CONTACT, &in_header, &matchoff, &matchlen, &addr, &port) > 0) { - if (!map_addr(skb, dataoff, dptr, datalen, matchoff, matchlen, + if (!map_addr(skb, protoff, dataoff, dptr, datalen, + matchoff, matchlen, &addr, port)) return NF_DROP; } - if (!map_sip_addr(skb, dataoff, dptr, datalen, SIP_HDR_FROM) || - !map_sip_addr(skb, dataoff, dptr, datalen, SIP_HDR_TO)) + if (!map_sip_addr(skb, protoff, dataoff, dptr, datalen, SIP_HDR_FROM) || + !map_sip_addr(skb, protoff, dataoff, dptr, datalen, SIP_HDR_TO)) return NF_DROP; return NF_ACCEPT; @@ -272,7 +277,8 @@ static void ip_nat_sip_expected(struct nf_conn *ct, } } -static unsigned int ip_nat_sip_expect(struct sk_buff *skb, unsigned int dataoff, +static unsigned int ip_nat_sip_expect(struct sk_buff *skb, unsigned int protoff, + unsigned int dataoff, const char **dptr, unsigned int *datalen, struct nf_conntrack_expect *exp, unsigned int matchoff, @@ -326,7 +332,7 @@ static unsigned int ip_nat_sip_expect(struct sk_buff *skb, unsigned int dataoff, if (exp->tuple.dst.u3.ip != exp->saved_ip || exp->tuple.dst.u.udp.port != exp->saved_proto.udp.port) { buflen = sprintf(buffer, "%pI4:%u", &newip, port); - if (!mangle_packet(skb, dataoff, dptr, datalen, + if (!mangle_packet(skb, protoff, dataoff, dptr, datalen, matchoff, matchlen, buffer, buflen)) goto err; } @@ -337,7 +343,8 @@ err: return NF_DROP; } -static int mangle_content_len(struct sk_buff *skb, unsigned int dataoff, +static int mangle_content_len(struct sk_buff *skb, unsigned int protoff, + unsigned int dataoff, const char **dptr, unsigned int *datalen) { enum ip_conntrack_info ctinfo; @@ -359,11 +366,12 @@ static int mangle_content_len(struct sk_buff *skb, unsigned int dataoff, return 0; buflen = sprintf(buffer, "%u", c_len); - return mangle_packet(skb, dataoff, dptr, datalen, matchoff, matchlen, - buffer, buflen); + return mangle_packet(skb, protoff, dataoff, dptr, datalen, + matchoff, matchlen, buffer, buflen); } -static int mangle_sdp_packet(struct sk_buff *skb, unsigned int dataoff, +static int mangle_sdp_packet(struct sk_buff *skb, unsigned int protoff, + unsigned int dataoff, const char **dptr, unsigned int *datalen, unsigned int sdpoff, enum sdp_header_types type, @@ -377,11 +385,12 @@ static int mangle_sdp_packet(struct sk_buff *skb, unsigned int dataoff, if (ct_sip_get_sdp_header(ct, *dptr, sdpoff, *datalen, type, term, &matchoff, &matchlen) <= 0) return -ENOENT; - return mangle_packet(skb, dataoff, dptr, datalen, matchoff, matchlen, - buffer, buflen) ? 0 : -EINVAL; + return mangle_packet(skb, protoff, dataoff, dptr, datalen, + matchoff, matchlen, buffer, buflen) ? 0 : -EINVAL; } -static unsigned int ip_nat_sdp_addr(struct sk_buff *skb, unsigned int dataoff, +static unsigned int ip_nat_sdp_addr(struct sk_buff *skb, unsigned int protoff, + unsigned int dataoff, const char **dptr, unsigned int *datalen, unsigned int sdpoff, enum sdp_header_types type, @@ -392,14 +401,15 @@ static unsigned int ip_nat_sdp_addr(struct sk_buff *skb, unsigned int dataoff, unsigned int buflen; buflen = sprintf(buffer, "%pI4", &addr->ip); - if (mangle_sdp_packet(skb, dataoff, dptr, datalen, sdpoff, type, term, - buffer, buflen)) + if (mangle_sdp_packet(skb, protoff, dataoff, dptr, datalen, + sdpoff, type, term, buffer, buflen)) return 0; - return mangle_content_len(skb, dataoff, dptr, datalen); + return mangle_content_len(skb, protoff, dataoff, dptr, datalen); } -static unsigned int ip_nat_sdp_port(struct sk_buff *skb, unsigned int dataoff, +static unsigned int ip_nat_sdp_port(struct sk_buff *skb, unsigned int protoff, + unsigned int dataoff, const char **dptr, unsigned int *datalen, unsigned int matchoff, unsigned int matchlen, @@ -409,14 +419,15 @@ static unsigned int ip_nat_sdp_port(struct sk_buff *skb, unsigned int dataoff, unsigned int buflen; buflen = sprintf(buffer, "%u", port); - if (!mangle_packet(skb, dataoff, dptr, datalen, matchoff, matchlen, - buffer, buflen)) + if (!mangle_packet(skb, protoff, dataoff, dptr, datalen, + matchoff, matchlen, buffer, buflen)) return 0; - return mangle_content_len(skb, dataoff, dptr, datalen); + return mangle_content_len(skb, protoff, dataoff, dptr, datalen); } -static unsigned int ip_nat_sdp_session(struct sk_buff *skb, unsigned int dataoff, +static unsigned int ip_nat_sdp_session(struct sk_buff *skb, unsigned int protoff, + unsigned int dataoff, const char **dptr, unsigned int *datalen, unsigned int sdpoff, const union nf_inet_addr *addr) @@ -426,12 +437,12 @@ static unsigned int ip_nat_sdp_session(struct sk_buff *skb, unsigned int dataoff /* Mangle session description owner and contact addresses */ buflen = sprintf(buffer, "%pI4", &addr->ip); - if (mangle_sdp_packet(skb, dataoff, dptr, datalen, sdpoff, + if (mangle_sdp_packet(skb, protoff, dataoff, dptr, datalen, sdpoff, SDP_HDR_OWNER_IP4, SDP_HDR_MEDIA, buffer, buflen)) return 0; - switch (mangle_sdp_packet(skb, dataoff, dptr, datalen, sdpoff, + switch (mangle_sdp_packet(skb, protoff, dataoff, dptr, datalen, sdpoff, SDP_HDR_CONNECTION_IP4, SDP_HDR_MEDIA, buffer, buflen)) { case 0: @@ -448,12 +459,13 @@ static unsigned int ip_nat_sdp_session(struct sk_buff *skb, unsigned int dataoff return 0; } - return mangle_content_len(skb, dataoff, dptr, datalen); + return mangle_content_len(skb, protoff, dataoff, dptr, datalen); } /* So, this packet has hit the connection tracking matching code. Mangle it, and change the expectation to match the new version. */ -static unsigned int ip_nat_sdp_media(struct sk_buff *skb, unsigned int dataoff, +static unsigned int ip_nat_sdp_media(struct sk_buff *skb, unsigned int protoff, + unsigned int dataoff, const char **dptr, unsigned int *datalen, struct nf_conntrack_expect *rtp_exp, struct nf_conntrack_expect *rtcp_exp, @@ -514,7 +526,7 @@ static unsigned int ip_nat_sdp_media(struct sk_buff *skb, unsigned int dataoff, /* Update media port. */ if (rtp_exp->tuple.dst.u.udp.port != rtp_exp->saved_proto.udp.port && - !ip_nat_sdp_port(skb, dataoff, dptr, datalen, + !ip_nat_sdp_port(skb, protoff, dataoff, dptr, datalen, mediaoff, medialen, port)) goto err2; -- cgit v1.2.3-55-g7522