1/*
2 * (C) 2006-2011 by Pablo Neira Ayuso <pablo@netfilter.org>
3 * (C) 2011 by Vyatta Inc. <http://www.vyatta.com>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
18 */
19
20#include "conntrackd.h"
21#include "network.h"
22#include "log.h"
23
24#include <stdlib.h>
25#include <time.h>
26#include <string.h>
27
28#define NETHDR_ALIGNTO	4
29
30static unsigned int seq_set, cur_seq;
31
32int nethdr_align(int value)
33{
34	return (value + NETHDR_ALIGNTO - 1) & ~(NETHDR_ALIGNTO - 1);
35}
36
37int nethdr_size(int len)
38{
39	return NETHDR_SIZ + len;
40}
41
42static inline void __nethdr_set(struct nethdr *net, int len)
43{
44	if (!seq_set) {
45		seq_set = 1;
46		cur_seq = time(NULL);
47	}
48	net->version	= CONNTRACKD_PROTOCOL_VERSION;
49	net->len	= len;
50	net->seq	= cur_seq++;
51}
52
53void nethdr_set(struct nethdr *net, int type)
54{
55	__nethdr_set(net, NETHDR_SIZ);
56	net->type = type;
57}
58
59void nethdr_set_ack(struct nethdr *net)
60{
61	__nethdr_set(net, NETHDR_ACK_SIZ);
62}
63
64void nethdr_set_ctl(struct nethdr *net)
65{
66	__nethdr_set(net, NETHDR_SIZ);
67}
68
69static int local_seq_set = 0;
70
71/* this function only tracks, it does not update the last sequence received */
72int nethdr_track_seq(uint32_t seq, uint32_t *exp_seq)
73{
74	int ret = SEQ_UNKNOWN;
75
76	/* netlink sequence tracking initialization */
77	if (!local_seq_set) {
78		ret = SEQ_UNSET;
79		goto out;
80	}
81
82	/* fast path: we received the correct sequence */
83	if (seq == STATE_SYNC(last_seq_recv)+1) {
84		ret = SEQ_IN_SYNC;
85		goto out;
86	}
87
88	/* out of sequence: some messages got lost */
89	if (after(seq, STATE_SYNC(last_seq_recv)+1)) {
90		STATE_SYNC(error).msg_rcv_lost +=
91					seq - STATE_SYNC(last_seq_recv) + 1;
92		ret = SEQ_AFTER;
93		goto out;
94	}
95
96	/* out of sequence: replayed/delayed packet? */
97	if (before(seq, STATE_SYNC(last_seq_recv)+1)) {
98		STATE_SYNC(error).msg_rcv_before++;
99		ret = SEQ_BEFORE;
100	}
101
102out:
103	*exp_seq = STATE_SYNC(last_seq_recv)+1;
104
105	return ret;
106}
107
108void nethdr_track_update_seq(uint32_t seq)
109{
110	if (!local_seq_set)
111		local_seq_set = 1;
112
113	STATE_SYNC(last_seq_recv) = seq;
114}
115
116int nethdr_track_is_seq_set()
117{
118	return local_seq_set;
119}
120
121#include "cache.h"
122
123static int status2type[CACHE_T_MAX][C_OBJ_MAX] = {
124	[CACHE_T_CT] = {
125		[C_OBJ_NEW]	= NET_T_STATE_CT_NEW,
126		[C_OBJ_ALIVE]	= NET_T_STATE_CT_UPD,
127		[C_OBJ_DEAD]	= NET_T_STATE_CT_DEL,
128	},
129	[CACHE_T_EXP] = {
130		[C_OBJ_NEW]	= NET_T_STATE_EXP_NEW,
131		[C_OBJ_ALIVE]	= NET_T_STATE_EXP_UPD,
132		[C_OBJ_DEAD]	= NET_T_STATE_EXP_DEL,
133	},
134};
135
136int object_status_to_network_type(struct cache_object *obj)
137{
138	return status2type[obj->cache->type][obj->status];
139}
140