0c4e966eaf
CONFIG_NF_NAT_PROTO_DCCP is no more a tristate. When set to y, NAT support for DCCP protocol is built-in into nf_nat.ko. footprint test: (nf_nat_proto_) | dccp || nf_nat --------------------------+--------++-------- no builtin | 409800 || 2241312 DCCP builtin | - || 2578968 Signed-off-by: Davide Caratti <dcaratti@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
83 lines
2.1 KiB
C
83 lines
2.1 KiB
C
/*
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* DCCP NAT protocol helper
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*
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* Copyright (c) 2005, 2006, 2008 Patrick McHardy <kaber@trash.net>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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*/
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#include <linux/kernel.h>
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#include <linux/skbuff.h>
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#include <linux/dccp.h>
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#include <net/netfilter/nf_conntrack.h>
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#include <net/netfilter/nf_nat.h>
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#include <net/netfilter/nf_nat_l3proto.h>
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#include <net/netfilter/nf_nat_l4proto.h>
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static u_int16_t dccp_port_rover;
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static void
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dccp_unique_tuple(const struct nf_nat_l3proto *l3proto,
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struct nf_conntrack_tuple *tuple,
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const struct nf_nat_range *range,
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enum nf_nat_manip_type maniptype,
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const struct nf_conn *ct)
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{
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nf_nat_l4proto_unique_tuple(l3proto, tuple, range, maniptype, ct,
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&dccp_port_rover);
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}
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static bool
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dccp_manip_pkt(struct sk_buff *skb,
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const struct nf_nat_l3proto *l3proto,
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unsigned int iphdroff, unsigned int hdroff,
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const struct nf_conntrack_tuple *tuple,
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enum nf_nat_manip_type maniptype)
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{
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struct dccp_hdr *hdr;
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__be16 *portptr, oldport, newport;
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int hdrsize = 8; /* DCCP connection tracking guarantees this much */
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if (skb->len >= hdroff + sizeof(struct dccp_hdr))
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hdrsize = sizeof(struct dccp_hdr);
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if (!skb_make_writable(skb, hdroff + hdrsize))
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return false;
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hdr = (struct dccp_hdr *)(skb->data + hdroff);
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if (maniptype == NF_NAT_MANIP_SRC) {
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newport = tuple->src.u.dccp.port;
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portptr = &hdr->dccph_sport;
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} else {
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newport = tuple->dst.u.dccp.port;
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portptr = &hdr->dccph_dport;
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}
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oldport = *portptr;
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*portptr = newport;
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if (hdrsize < sizeof(*hdr))
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return true;
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l3proto->csum_update(skb, iphdroff, &hdr->dccph_checksum,
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tuple, maniptype);
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inet_proto_csum_replace2(&hdr->dccph_checksum, skb, oldport, newport,
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false);
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return true;
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}
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const struct nf_nat_l4proto nf_nat_l4proto_dccp = {
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.l4proto = IPPROTO_DCCP,
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.manip_pkt = dccp_manip_pkt,
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.in_range = nf_nat_l4proto_in_range,
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.unique_tuple = dccp_unique_tuple,
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#if IS_ENABLED(CONFIG_NF_CT_NETLINK)
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.nlattr_to_range = nf_nat_l4proto_nlattr_to_range,
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#endif
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};
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