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
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
|
/*
* (C) 2012-2013 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 code has been sponsored by Sophos Astaro <http://www.sophos.com>
*/
#include "internal.h"
#include <stdio.h>
#include <stdint.h>
#include <string.h> /* for memcpy */
#include <arpa/inet.h>
#include <errno.h>
#include <libmnl/libmnl.h>
#include <linux/netfilter/nf_tables.h>
#include <libnftnl/rule.h>
#include <libnftnl/expr.h>
struct nftnl_expr_lookup {
enum nft_registers sreg;
enum nft_registers dreg;
char *set_name;
uint32_t set_id;
uint32_t flags;
};
static int
nftnl_expr_lookup_set(struct nftnl_expr *e, uint16_t type,
const void *data, uint32_t data_len)
{
struct nftnl_expr_lookup *lookup = nftnl_expr_data(e);
switch(type) {
case NFTNL_EXPR_LOOKUP_SREG:
memcpy(&lookup->sreg, data, sizeof(lookup->sreg));
break;
case NFTNL_EXPR_LOOKUP_DREG:
memcpy(&lookup->dreg, data, sizeof(lookup->dreg));
break;
case NFTNL_EXPR_LOOKUP_SET:
lookup->set_name = strdup((const char *)data);
if (!lookup->set_name)
return -1;
break;
case NFTNL_EXPR_LOOKUP_SET_ID:
memcpy(&lookup->set_id, data, sizeof(lookup->set_id));
break;
case NFTNL_EXPR_LOOKUP_FLAGS:
memcpy(&lookup->flags, data, sizeof(lookup->flags));
break;
default:
return -1;
}
return 0;
}
static const void *
nftnl_expr_lookup_get(const struct nftnl_expr *e, uint16_t type,
uint32_t *data_len)
{
struct nftnl_expr_lookup *lookup = nftnl_expr_data(e);
switch(type) {
case NFTNL_EXPR_LOOKUP_SREG:
*data_len = sizeof(lookup->sreg);
return &lookup->sreg;
case NFTNL_EXPR_LOOKUP_DREG:
*data_len = sizeof(lookup->dreg);
return &lookup->dreg;
case NFTNL_EXPR_LOOKUP_SET:
*data_len = strlen(lookup->set_name) + 1;
return lookup->set_name;
case NFTNL_EXPR_LOOKUP_SET_ID:
*data_len = sizeof(lookup->set_id);
return &lookup->set_id;
case NFTNL_EXPR_LOOKUP_FLAGS:
*data_len = sizeof(lookup->flags);
return &lookup->flags;
}
return NULL;
}
static int nftnl_expr_lookup_cb(const struct nlattr *attr, void *data)
{
const struct nlattr **tb = data;
int type = mnl_attr_get_type(attr);
if (mnl_attr_type_valid(attr, NFTA_LOOKUP_MAX) < 0)
return MNL_CB_OK;
switch(type) {
case NFTA_LOOKUP_SREG:
case NFTA_LOOKUP_DREG:
case NFTA_LOOKUP_SET_ID:
case NFTA_LOOKUP_FLAGS:
if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
abi_breakage();
break;
case NFTA_LOOKUP_SET:
if (mnl_attr_validate(attr, MNL_TYPE_STRING) < 0)
abi_breakage();
break;
}
tb[type] = attr;
return MNL_CB_OK;
}
static void
nftnl_expr_lookup_build(struct nlmsghdr *nlh, const struct nftnl_expr *e)
{
struct nftnl_expr_lookup *lookup = nftnl_expr_data(e);
if (e->flags & (1 << NFTNL_EXPR_LOOKUP_SREG))
mnl_attr_put_u32(nlh, NFTA_LOOKUP_SREG, htonl(lookup->sreg));
if (e->flags & (1 << NFTNL_EXPR_LOOKUP_DREG))
mnl_attr_put_u32(nlh, NFTA_LOOKUP_DREG, htonl(lookup->dreg));
if (e->flags & (1 << NFTNL_EXPR_LOOKUP_SET))
mnl_attr_put_strz(nlh, NFTA_LOOKUP_SET, lookup->set_name);
if (e->flags & (1 << NFTNL_EXPR_LOOKUP_SET_ID))
mnl_attr_put_u32(nlh, NFTA_LOOKUP_SET_ID,
htonl(lookup->set_id));
if (e->flags & (1 << NFTNL_EXPR_LOOKUP_FLAGS))
mnl_attr_put_u32(nlh, NFTA_LOOKUP_FLAGS, htonl(lookup->flags));
}
static int
nftnl_expr_lookup_parse(struct nftnl_expr *e, struct nlattr *attr)
{
struct nftnl_expr_lookup *lookup = nftnl_expr_data(e);
struct nlattr *tb[NFTA_LOOKUP_MAX+1] = {};
int ret = 0;
if (mnl_attr_parse_nested(attr, nftnl_expr_lookup_cb, tb) < 0)
return -1;
if (tb[NFTA_LOOKUP_SREG]) {
lookup->sreg = ntohl(mnl_attr_get_u32(tb[NFTA_LOOKUP_SREG]));
e->flags |= (1 << NFTNL_EXPR_LOOKUP_SREG);
}
if (tb[NFTA_LOOKUP_DREG]) {
lookup->dreg = ntohl(mnl_attr_get_u32(tb[NFTA_LOOKUP_DREG]));
e->flags |= (1 << NFTNL_EXPR_LOOKUP_DREG);
}
if (tb[NFTA_LOOKUP_SET]) {
lookup->set_name =
strdup(mnl_attr_get_str(tb[NFTA_LOOKUP_SET]));
if (!lookup->set_name)
return -1;
e->flags |= (1 << NFTNL_EXPR_LOOKUP_SET);
}
if (tb[NFTA_LOOKUP_SET_ID]) {
lookup->set_id =
ntohl(mnl_attr_get_u32(tb[NFTA_LOOKUP_SET_ID]));
e->flags |= (1 << NFTNL_EXPR_LOOKUP_SET_ID);
}
if (tb[NFTA_LOOKUP_FLAGS]) {
lookup->flags = ntohl(mnl_attr_get_u32(tb[NFTA_LOOKUP_FLAGS]));
e->flags |= (1 << NFTNL_EXPR_LOOKUP_FLAGS);
}
return ret;
}
static int
nftnl_expr_lookup_snprintf(char *buf, size_t remain,
uint32_t flags, const struct nftnl_expr *e)
{
struct nftnl_expr_lookup *l = nftnl_expr_data(e);
int offset = 0, ret;
ret = snprintf(buf, remain, "reg %u set %s ", l->sreg, l->set_name);
SNPRINTF_BUFFER_SIZE(ret, remain, offset);
if (e->flags & (1 << NFTNL_EXPR_LOOKUP_DREG)) {
ret = snprintf(buf + offset, remain, "dreg %u ", l->dreg);
SNPRINTF_BUFFER_SIZE(ret, remain, offset);
}
if (e->flags & (1 << NFTNL_EXPR_LOOKUP_FLAGS)) {
ret = snprintf(buf + offset, remain, "0x%x ", l->flags);
SNPRINTF_BUFFER_SIZE(ret, remain, offset);
}
return offset;
}
static void nftnl_expr_lookup_free(const struct nftnl_expr *e)
{
struct nftnl_expr_lookup *lookup = nftnl_expr_data(e);
xfree(lookup->set_name);
}
struct expr_ops expr_ops_lookup = {
.name = "lookup",
.alloc_len = sizeof(struct nftnl_expr_lookup),
.max_attr = NFTA_LOOKUP_MAX,
.free = nftnl_expr_lookup_free,
.set = nftnl_expr_lookup_set,
.get = nftnl_expr_lookup_get,
.parse = nftnl_expr_lookup_parse,
.build = nftnl_expr_lookup_build,
.snprintf = nftnl_expr_lookup_snprintf,
};
|
