libnftnl 1.2.7
meta.c
1/*
2 * (C) 2012 by Pablo Neira Ayuso <pablo@netfilter.org>
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published
6 * by the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This code has been sponsored by Sophos Astaro <http://www.sophos.com>
10 */
11
12#include <stdio.h>
13#include <stdint.h>
14#include <string.h>
15#include <arpa/inet.h>
16#include <errno.h>
17#include <linux/netfilter/nf_tables.h>
18
19#include "internal.h"
20#include <libmnl/libmnl.h>
21#include <libnftnl/expr.h>
22#include <libnftnl/rule.h>
23
24#ifndef NFT_META_MAX
25#define NFT_META_MAX (NFT_META_BRI_BROUTE + 1)
26#endif
27
29 enum nft_meta_keys key;
30 enum nft_registers dreg;
31 enum nft_registers sreg;
32};
33
34static int
35nftnl_expr_meta_set(struct nftnl_expr *e, uint16_t type,
36 const void *data, uint32_t data_len)
37{
38 struct nftnl_expr_meta *meta = nftnl_expr_data(e);
39
40 switch(type) {
41 case NFTNL_EXPR_META_KEY:
42 memcpy(&meta->key, data, data_len);
43 break;
44 case NFTNL_EXPR_META_DREG:
45 memcpy(&meta->dreg, data, data_len);
46 break;
47 case NFTNL_EXPR_META_SREG:
48 memcpy(&meta->sreg, data, data_len);
49 break;
50 }
51 return 0;
52}
53
54static const void *
55nftnl_expr_meta_get(const struct nftnl_expr *e, uint16_t type,
56 uint32_t *data_len)
57{
58 struct nftnl_expr_meta *meta = nftnl_expr_data(e);
59
60 switch(type) {
61 case NFTNL_EXPR_META_KEY:
62 *data_len = sizeof(meta->key);
63 return &meta->key;
64 case NFTNL_EXPR_META_DREG:
65 *data_len = sizeof(meta->dreg);
66 return &meta->dreg;
67 case NFTNL_EXPR_META_SREG:
68 *data_len = sizeof(meta->sreg);
69 return &meta->sreg;
70 }
71 return NULL;
72}
73
74static int nftnl_expr_meta_cb(const struct nlattr *attr, void *data)
75{
76 const struct nlattr **tb = data;
77 int type = mnl_attr_get_type(attr);
78
79 if (mnl_attr_type_valid(attr, NFTA_META_MAX) < 0)
80 return MNL_CB_OK;
81
82 switch(type) {
83 case NFTA_META_KEY:
84 case NFTA_META_DREG:
85 case NFTA_META_SREG:
86 if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
87 abi_breakage();
88 break;
89 }
90
91 tb[type] = attr;
92 return MNL_CB_OK;
93}
94
95static void
96nftnl_expr_meta_build(struct nlmsghdr *nlh, const struct nftnl_expr *e)
97{
98 struct nftnl_expr_meta *meta = nftnl_expr_data(e);
99
100 if (e->flags & (1 << NFTNL_EXPR_META_KEY))
101 mnl_attr_put_u32(nlh, NFTA_META_KEY, htonl(meta->key));
102 if (e->flags & (1 << NFTNL_EXPR_META_DREG))
103 mnl_attr_put_u32(nlh, NFTA_META_DREG, htonl(meta->dreg));
104 if (e->flags & (1 << NFTNL_EXPR_META_SREG))
105 mnl_attr_put_u32(nlh, NFTA_META_SREG, htonl(meta->sreg));
106}
107
108static int
109nftnl_expr_meta_parse(struct nftnl_expr *e, struct nlattr *attr)
110{
111 struct nftnl_expr_meta *meta = nftnl_expr_data(e);
112 struct nlattr *tb[NFTA_META_MAX+1] = {};
113
114 if (mnl_attr_parse_nested(attr, nftnl_expr_meta_cb, tb) < 0)
115 return -1;
116
117 if (tb[NFTA_META_KEY]) {
118 meta->key = ntohl(mnl_attr_get_u32(tb[NFTA_META_KEY]));
119 e->flags |= (1 << NFTNL_EXPR_META_KEY);
120 }
121 if (tb[NFTA_META_DREG]) {
122 meta->dreg = ntohl(mnl_attr_get_u32(tb[NFTA_META_DREG]));
123 e->flags |= (1 << NFTNL_EXPR_META_DREG);
124 }
125 if (tb[NFTA_META_SREG]) {
126 meta->sreg = ntohl(mnl_attr_get_u32(tb[NFTA_META_SREG]));
127 e->flags |= (1 << NFTNL_EXPR_META_SREG);
128 }
129
130 return 0;
131}
132
133static const char *meta_key2str_array[NFT_META_MAX] = {
134 [NFT_META_LEN] = "len",
135 [NFT_META_PROTOCOL] = "protocol",
136 [NFT_META_NFPROTO] = "nfproto",
137 [NFT_META_L4PROTO] = "l4proto",
138 [NFT_META_PRIORITY] = "priority",
139 [NFT_META_MARK] = "mark",
140 [NFT_META_IIF] = "iif",
141 [NFT_META_OIF] = "oif",
142 [NFT_META_IIFNAME] = "iifname",
143 [NFT_META_OIFNAME] = "oifname",
144 [NFT_META_IIFTYPE] = "iiftype",
145 [NFT_META_OIFTYPE] = "oiftype",
146 [NFT_META_SKUID] = "skuid",
147 [NFT_META_SKGID] = "skgid",
148 [NFT_META_NFTRACE] = "nftrace",
149 [NFT_META_RTCLASSID] = "rtclassid",
150 [NFT_META_SECMARK] = "secmark",
151 [NFT_META_BRI_IIFNAME] = "bri_iifname",
152 [NFT_META_BRI_OIFNAME] = "bri_oifname",
153 [NFT_META_PKTTYPE] = "pkttype",
154 [NFT_META_CPU] = "cpu",
155 [NFT_META_IIFGROUP] = "iifgroup",
156 [NFT_META_OIFGROUP] = "oifgroup",
157 [NFT_META_CGROUP] = "cgroup",
158 [NFT_META_PRANDOM] = "prandom",
159 [NFT_META_SECPATH] = "secpath",
160 [NFT_META_IIFKIND] = "iifkind",
161 [NFT_META_OIFKIND] = "oifkind",
162 [NFT_META_BRI_IIFPVID] = "bri_iifpvid",
163 [NFT_META_BRI_IIFVPROTO] = "bri_iifvproto",
164 [NFT_META_TIME_NS] = "time",
165 [NFT_META_TIME_DAY] = "day",
166 [NFT_META_TIME_HOUR] = "hour",
167 [NFT_META_SDIF] = "sdif",
168 [NFT_META_SDIFNAME] = "sdifname",
169 [NFT_META_BRI_BROUTE] = "broute",
170};
171
172static const char *meta_key2str(uint8_t key)
173{
174 if (key < NFT_META_MAX)
175 return meta_key2str_array[key];
176
177 return "unknown";
178}
179
180static inline int str2meta_key(const char *str)
181{
182 int i;
183
184 for (i = 0; i < NFT_META_MAX; i++) {
185 if (strcmp(str, meta_key2str_array[i]) == 0)
186 return i;
187 }
188
189 errno = EINVAL;
190 return -1;
191}
192
193static int
194nftnl_expr_meta_snprintf(char *buf, size_t len,
195 uint32_t flags, const struct nftnl_expr *e)
196{
197 struct nftnl_expr_meta *meta = nftnl_expr_data(e);
198
199 if (e->flags & (1 << NFTNL_EXPR_META_SREG)) {
200 return snprintf(buf, len, "set %s with reg %u ",
201 meta_key2str(meta->key), meta->sreg);
202 }
203 if (e->flags & (1 << NFTNL_EXPR_META_DREG)) {
204 return snprintf(buf, len, "load %s => reg %u ",
205 meta_key2str(meta->key), meta->dreg);
206 }
207 return 0;
208}
209
210static struct attr_policy meta_attr_policy[__NFTNL_EXPR_META_MAX] = {
211 [NFTNL_EXPR_META_KEY] = { .maxlen = sizeof(uint32_t) },
212 [NFTNL_EXPR_META_DREG] = { .maxlen = sizeof(uint32_t) },
213 [NFTNL_EXPR_META_SREG] = { .maxlen = sizeof(uint32_t) },
214};
215
216struct expr_ops expr_ops_meta = {
217 .name = "meta",
218 .alloc_len = sizeof(struct nftnl_expr_meta),
219 .nftnl_max_attr = __NFTNL_EXPR_META_MAX - 1,
220 .attr_policy = meta_attr_policy,
221 .set = nftnl_expr_meta_set,
222 .get = nftnl_expr_meta_get,
223 .parse = nftnl_expr_meta_parse,
224 .build = nftnl_expr_meta_build,
225 .output = nftnl_expr_meta_snprintf,
226};