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/*
* (C) 2006-2007 by Pablo Neira Ayuso <pablo@netfilter.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include "network.h"
#include <libnetfilter_conntrack/libnetfilter_conntrack.h>
#ifndef ssizeof
#define ssizeof(x) (int)sizeof(x)
#endif
static void parse_u8(struct nf_conntrack *ct, int attr, void *data);
static void parse_u16(struct nf_conntrack *ct, int attr, void *data);
static void parse_u32(struct nf_conntrack *ct, int attr, void *data);
static void parse_group(struct nf_conntrack *ct, int attr, void *data);
static void parse_nat_seq_adj(struct nf_conntrack *ct, int attr, void *data);
struct parser {
void (*parse)(struct nf_conntrack *ct, int attr, void *data);
int attr;
int size;
};
static struct parser h[NTA_MAX] = {
[NTA_IPV4] = {
.parse = parse_group,
.attr = ATTR_GRP_ORIG_IPV4,
.size = NTA_SIZE(sizeof(struct nfct_attr_grp_ipv4)),
},
[NTA_IPV6] = {
.parse = parse_group,
.attr = ATTR_GRP_ORIG_IPV6,
.size = NTA_SIZE(sizeof(struct nfct_attr_grp_ipv6)),
},
[NTA_PORT] = {
.parse = parse_group,
.attr = ATTR_GRP_ORIG_PORT,
.size = NTA_SIZE(sizeof(struct nfct_attr_grp_port)),
},
[NTA_L4PROTO] = {
.parse = parse_u8,
.attr = ATTR_L4PROTO,
.size = NTA_SIZE(sizeof(uint8_t)),
},
[NTA_TCP_STATE] = {
.parse = parse_u8,
.attr = ATTR_TCP_STATE,
.size = NTA_SIZE(sizeof(uint8_t)),
},
[NTA_STATUS] = {
.parse = parse_u32,
.attr = ATTR_STATUS,
.size = NTA_SIZE(sizeof(uint32_t)),
},
[NTA_MARK] = {
.parse = parse_u32,
.attr = ATTR_MARK,
.size = NTA_SIZE(sizeof(uint32_t)),
},
[NTA_TIMEOUT] = {
.parse = parse_u32,
.attr = ATTR_TIMEOUT,
.size = NTA_SIZE(sizeof(uint32_t)),
},
[NTA_MASTER_IPV4] = {
.parse = parse_group,
.attr = ATTR_GRP_MASTER_IPV4,
.size = NTA_SIZE(sizeof(struct nfct_attr_grp_ipv4)),
},
[NTA_MASTER_IPV6] = {
.parse = parse_group,
.attr = ATTR_GRP_MASTER_IPV6,
.size = NTA_SIZE(sizeof(struct nfct_attr_grp_ipv6)),
},
[NTA_MASTER_L4PROTO] = {
.parse = parse_u8,
.attr = ATTR_MASTER_L4PROTO,
.size = NTA_SIZE(sizeof(uint8_t)),
},
[NTA_MASTER_PORT] = {
.parse = parse_group,
.attr = ATTR_GRP_MASTER_PORT,
.size = NTA_SIZE(sizeof(struct nfct_attr_grp_port)),
},
[NTA_SNAT_IPV4] = {
.parse = parse_u32,
.attr = ATTR_SNAT_IPV4,
.size = NTA_SIZE(sizeof(uint32_t)),
},
[NTA_DNAT_IPV4] = {
.parse = parse_u32,
.attr = ATTR_DNAT_IPV4,
.size = NTA_SIZE(sizeof(uint32_t)),
},
[NTA_SPAT_PORT] = {
.parse = parse_u16,
.attr = ATTR_SNAT_PORT,
.size = NTA_SIZE(sizeof(uint16_t)),
},
[NTA_DPAT_PORT] = {
.parse = parse_u16,
.attr = ATTR_DNAT_PORT,
.size = NTA_SIZE(sizeof(uint16_t)),
},
[NTA_NAT_SEQ_ADJ] = {
.parse = parse_nat_seq_adj,
.size = NTA_SIZE(sizeof(struct nta_attr_natseqadj)),
},
[NTA_SCTP_STATE] = {
.parse = parse_u8,
.attr = ATTR_SCTP_STATE,
.size = NTA_SIZE(sizeof(uint8_t)),
},
[NTA_SCTP_VTAG_ORIG] = {
.parse = parse_u32,
.attr = ATTR_SCTP_VTAG_ORIG,
.size = NTA_SIZE(sizeof(uint32_t)),
},
[NTA_SCTP_VTAG_REPL] = {
.parse = parse_u32,
.attr = ATTR_SCTP_VTAG_REPL,
.size = NTA_SIZE(sizeof(uint32_t)),
},
[NTA_DCCP_STATE] = {
.parse = parse_u8,
.attr = ATTR_DCCP_STATE,
.size = NTA_SIZE(sizeof(uint8_t)),
},
[NTA_DCCP_ROLE] = {
.parse = parse_u8,
.attr = ATTR_DCCP_ROLE,
.size = NTA_SIZE(sizeof(uint8_t)),
},
};
static void
parse_u8(struct nf_conntrack *ct, int attr, void *data)
{
uint8_t *value = (uint8_t *) data;
nfct_set_attr_u8(ct, h[attr].attr, *value);
}
static void
parse_u16(struct nf_conntrack *ct, int attr, void *data)
{
uint16_t *value = (uint16_t *) data;
nfct_set_attr_u16(ct, h[attr].attr, ntohs(*value));
}
static void
parse_u32(struct nf_conntrack *ct, int attr, void *data)
{
uint32_t *value = (uint32_t *) data;
nfct_set_attr_u32(ct, h[attr].attr, ntohl(*value));
}
static void
parse_group(struct nf_conntrack *ct, int attr, void *data)
{
nfct_set_attr_grp(ct, h[attr].attr, data);
}
static void
parse_nat_seq_adj(struct nf_conntrack *ct, int attr, void *data)
{
struct nta_attr_natseqadj *this = data;
nfct_set_attr_u32(ct, ATTR_ORIG_NAT_SEQ_CORRECTION_POS,
ntohl(this->orig_seq_correction_pos));
nfct_set_attr_u32(ct, ATTR_ORIG_NAT_SEQ_OFFSET_BEFORE,
ntohl(this->orig_seq_correction_pos));
nfct_set_attr_u32(ct, ATTR_ORIG_NAT_SEQ_OFFSET_AFTER,
ntohl(this->orig_seq_correction_pos));
nfct_set_attr_u32(ct, ATTR_REPL_NAT_SEQ_CORRECTION_POS,
ntohl(this->orig_seq_correction_pos));
nfct_set_attr_u32(ct, ATTR_REPL_NAT_SEQ_OFFSET_BEFORE,
ntohl(this->orig_seq_correction_pos));
nfct_set_attr_u32(ct, ATTR_REPL_NAT_SEQ_OFFSET_AFTER,
ntohl(this->orig_seq_correction_pos));
}
int parse_payload(struct nf_conntrack *ct, struct nethdr *net, size_t remain)
{
int len;
struct netattr *attr;
if (remain < net->len)
return -1;
len = net->len - NETHDR_SIZ;
attr = NETHDR_DATA(net);
while (len > ssizeof(struct netattr)) {
ATTR_NETWORK2HOST(attr);
if (attr->nta_len > len)
return -1;
if (attr->nta_attr > NTA_MAX)
return -1;
if (attr->nta_len != h[attr->nta_attr].size)
return -1;
if (h[attr->nta_attr].parse == NULL) {
attr = NTA_NEXT(attr, len);
continue;
}
h[attr->nta_attr].parse(ct, attr->nta_attr, NTA_DATA(attr));
attr = NTA_NEXT(attr, len);
}
return 0;
}
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