summaryrefslogtreecommitdiffstats
path: root/src/obj/ct_helper.c
blob: a31bd6facccf9e4de275329e58617b67b6eb1166 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
/*
 * (C) 2017 Red Hat GmbH
 * Author: Florian Westphal <fw@strlen.de>
 *
 * 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.
 */

#include <stdio.h>
#include <stdint.h>
#include <arpa/inet.h>
#include <errno.h>
#include <inttypes.h>

#include <linux/netfilter/nf_tables.h>

#include "internal.h"
#include <libmnl/libmnl.h>
#include <libnftnl/object.h>

#include "obj.h"

static int nftnl_obj_ct_helper_set(struct nftnl_obj *e, uint16_t type,
				   const void *data, uint32_t data_len)
{
	struct nftnl_obj_ct_helper *helper = nftnl_obj_data(e);

	switch (type) {
	case NFTNL_OBJ_CT_HELPER_NAME:
		snprintf(helper->name, sizeof(helper->name), "%s", (const char *)data);
		break;
	case NFTNL_OBJ_CT_HELPER_L3PROTO:
		memcpy(&helper->l3proto, data, sizeof(helper->l3proto));
		break;
	case NFTNL_OBJ_CT_HELPER_L4PROTO:
		memcpy(&helper->l4proto, data, sizeof(helper->l4proto));
		break;
	default:
		return -1;
	}
	return 0;
}

static const void *nftnl_obj_ct_helper_get(const struct nftnl_obj *e,
					   uint16_t type, uint32_t *data_len)
{
	struct nftnl_obj_ct_helper *helper = nftnl_obj_data(e);

	switch (type) {
	case NFTNL_OBJ_CT_HELPER_NAME:
		*data_len = strlen(helper->name);
		return helper->name;
	case NFTNL_OBJ_CT_HELPER_L3PROTO:
		*data_len = sizeof(helper->l3proto);
		return &helper->l3proto;
	case NFTNL_OBJ_CT_HELPER_L4PROTO:
		*data_len = sizeof(helper->l4proto);
		return &helper->l4proto;
	}
	return NULL;
}

static int nftnl_obj_ct_helper_cb(const struct nlattr *attr, void *data)
{
	const struct nftnl_obj_ct_helper *helper = NULL;
	int type = mnl_attr_get_type(attr);
	const struct nlattr **tb = data;

	if (mnl_attr_type_valid(attr, NFTA_CT_HELPER_MAX) < 0)
		return MNL_CB_OK;

	switch (type) {
	case NFTA_CT_HELPER_NAME:
		if (mnl_attr_validate(attr, MNL_TYPE_STRING) < 0)
			abi_breakage();
		if (mnl_attr_get_payload_len(attr) >= sizeof(helper->name))
			abi_breakage();
		break;
	case NFTA_CT_HELPER_L3PROTO:
		if (mnl_attr_validate(attr, MNL_TYPE_U16) < 0)
			abi_breakage();
		break;
	case NFTA_CT_HELPER_L4PROTO:
		if (mnl_attr_validate(attr, MNL_TYPE_U8) < 0)
			abi_breakage();
		break;
	}

	tb[type] = attr;
	return MNL_CB_OK;
}

static void
nftnl_obj_ct_helper_build(struct nlmsghdr *nlh, const struct nftnl_obj *e)
{
	struct nftnl_obj_ct_helper *helper = nftnl_obj_data(e);

	if (e->flags & (1 << NFTNL_OBJ_CT_HELPER_NAME))
		mnl_attr_put_str(nlh, NFTA_CT_HELPER_NAME, helper->name);
	if (e->flags & (1 << NFTNL_OBJ_CT_HELPER_L3PROTO))
		mnl_attr_put_u16(nlh, NFTA_CT_HELPER_L3PROTO, htons(helper->l3proto));
	if (e->flags & (1 << NFTNL_OBJ_CT_HELPER_L4PROTO))
		mnl_attr_put_u8(nlh, NFTA_CT_HELPER_L4PROTO, helper->l4proto);
}

static int
nftnl_obj_ct_helper_parse(struct nftnl_obj *e, struct nlattr *attr)
{
	struct nftnl_obj_ct_helper *helper = nftnl_obj_data(e);
	struct nlattr *tb[NFTA_CT_HELPER_MAX + 1] = {};

	if (mnl_attr_parse_nested(attr, nftnl_obj_ct_helper_cb, tb) < 0)
		return -1;

	if (tb[NFTA_CT_HELPER_NAME]) {
		snprintf(helper->name, sizeof(helper->name), "%s",
			 mnl_attr_get_str(tb[NFTA_CT_HELPER_NAME]));
		e->flags |= (1 << NFTNL_OBJ_CT_HELPER_NAME);
	}
	if (tb[NFTA_CT_HELPER_L3PROTO]) {
		helper->l3proto = ntohs(mnl_attr_get_u16(tb[NFTA_CT_HELPER_L3PROTO]));
		e->flags |= (1 << NFTNL_OBJ_CT_HELPER_L3PROTO);
	}
	if (tb[NFTA_CT_HELPER_L4PROTO]) {
		helper->l4proto = mnl_attr_get_u8(tb[NFTA_CT_HELPER_L4PROTO]);
		e->flags |= (1 << NFTNL_OBJ_CT_HELPER_L4PROTO);
	}

	return 0;
}

static int nftnl_obj_ct_helper_snprintf(char *buf, size_t len,
				       uint32_t flags,
				       const struct nftnl_obj *e)
{
	struct nftnl_obj_ct_helper *helper = nftnl_obj_data(e);

	return snprintf(buf, len, "name %s family %d protocol %d ",
			helper->name, helper->l3proto, helper->l4proto);
}

struct obj_ops obj_ops_ct_helper = {
	.name		= "ct_helper",
	.type		= NFT_OBJECT_CT_HELPER,
	.alloc_len	= sizeof(struct nftnl_obj_ct_helper),
	.max_attr	= NFTA_CT_HELPER_MAX,
	.set		= nftnl_obj_ct_helper_set,
	.get		= nftnl_obj_ct_helper_get,
	.parse		= nftnl_obj_ct_helper_parse,
	.build		= nftnl_obj_ct_helper_build,
	.output		= nftnl_obj_ct_helper_snprintf,
};