1/*
2 * (C) 2005-2011 by Pablo Neira Ayuso <pablo@netfilter.org>
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 */
9
10#include "internal/internal.h"
11
12static int __parse_message(const struct nlmsghdr *nlh)
13{
14	uint16_t type = NFNL_MSG_TYPE(nlh->nlmsg_type);
15	uint16_t flags = nlh->nlmsg_flags;
16	int ret = NFCT_T_UNKNOWN;
17
18	switch(type) {
19	case IPCTNL_MSG_CT_NEW: /* same value for IPCTNL_MSG_EXP_NEW. */
20		if (flags & (NLM_F_CREATE|NLM_F_EXCL))
21			ret = NFCT_T_NEW;
22		else
23			ret = NFCT_T_UPDATE;
24		break;
25	case IPCTNL_MSG_CT_DELETE: /* same value for IPCTNL_MSG_EXP_DELETE. */
26		ret = NFCT_T_DESTROY;
27		break;
28	}
29	return ret;
30}
31
32int __callback(struct nlmsghdr *nlh, struct nfattr *nfa[], void *data)
33{
34	int ret = NFNL_CB_STOP;
35	unsigned int type;
36	struct nf_conntrack *ct = NULL;
37	struct nf_expect *exp = NULL;
38	struct __data_container *container = data;
39	uint8_t subsys = NFNL_SUBSYS_ID(nlh->nlmsg_type);
40
41	if (nlh->nlmsg_len < NLMSG_LENGTH(sizeof(struct nfgenmsg))) {
42		errno = EINVAL;
43		return NFNL_CB_FAILURE;
44	}
45	type = __parse_message(nlh);
46	if (!(type & container->type))
47		return NFNL_CB_CONTINUE;
48
49	switch(subsys) {
50	case NFNL_SUBSYS_CTNETLINK:
51		ct = nfct_new();
52		if (ct == NULL)
53			return NFNL_CB_FAILURE;
54
55		__parse_conntrack(nlh, nfa, ct);
56
57		if (container->h->cb) {
58			ret = container->h->cb(type, ct, container->data);
59		} else if (container->h->cb2) {
60			ret = container->h->cb2(nlh, type, ct,
61						container->data);
62		}
63		break;
64	case NFNL_SUBSYS_CTNETLINK_EXP:
65		exp = nfexp_new();
66		if (exp == NULL)
67			return NFNL_CB_FAILURE;
68
69		__parse_expect(nlh, nfa, exp);
70
71		if (container->h->expect_cb) {
72			ret = container->h->expect_cb(type, exp,
73						      container->data);
74		} else if (container->h->expect_cb2) {
75			ret = container->h->expect_cb2(nlh, type, exp,
76						       container->data);
77		}
78		break;
79	default:
80		errno = ENOTSUP;
81		ret = NFNL_CB_FAILURE;
82		break;
83	}
84
85	if (ret == NFCT_CB_STOLEN)
86		return NFNL_CB_CONTINUE;
87
88	if (ct)
89		nfct_destroy(ct);
90	if (exp)
91		nfexp_destroy(exp);
92
93	return ret;
94}
95