libnftnl 1.2.7
socket.c
1/*
2 * Copyright (c) 2018 Máté Eckl <ecklm94@gmail.com>
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
10#include <stdio.h>
11#include <stdint.h>
12#include <string.h>
13#include <arpa/inet.h>
14#include <errno.h>
15#include <linux/netfilter/nf_tables.h>
16
17#include "internal.h"
18#include <libmnl/libmnl.h>
19#include <libnftnl/expr.h>
20#include <libnftnl/rule.h>
21
23 enum nft_socket_keys key;
24 enum nft_registers dreg;
25 uint32_t level;
26};
27
28static int
29nftnl_expr_socket_set(struct nftnl_expr *e, uint16_t type,
30 const void *data, uint32_t data_len)
31{
32 struct nftnl_expr_socket *socket = nftnl_expr_data(e);
33
34 switch (type) {
35 case NFTNL_EXPR_SOCKET_KEY:
36 memcpy(&socket->key, data, data_len);
37 break;
38 case NFTNL_EXPR_SOCKET_DREG:
39 memcpy(&socket->dreg, data, data_len);
40 break;
41 case NFTNL_EXPR_SOCKET_LEVEL:
42 memcpy(&socket->level, data, data_len);
43 break;
44 }
45 return 0;
46}
47
48static const void *
49nftnl_expr_socket_get(const struct nftnl_expr *e, uint16_t type,
50 uint32_t *data_len)
51{
52 struct nftnl_expr_socket *socket = nftnl_expr_data(e);
53
54 switch (type) {
55 case NFTNL_EXPR_SOCKET_KEY:
56 *data_len = sizeof(socket->key);
57 return &socket->key;
58 case NFTNL_EXPR_SOCKET_DREG:
59 *data_len = sizeof(socket->dreg);
60 return &socket->dreg;
61 case NFTNL_EXPR_SOCKET_LEVEL:
62 *data_len = sizeof(socket->level);
63 return &socket->level;
64 }
65 return NULL;
66}
67
68static int nftnl_expr_socket_cb(const struct nlattr *attr, void *data)
69{
70 const struct nlattr **tb = data;
71 int type = mnl_attr_get_type(attr);
72
73 if (mnl_attr_type_valid(attr, NFTA_SOCKET_MAX) < 0)
74 return MNL_CB_OK;
75
76 switch (type) {
77 case NFTA_SOCKET_KEY:
78 case NFTA_SOCKET_DREG:
79 case NFTA_SOCKET_LEVEL:
80 if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
81 abi_breakage();
82 break;
83 }
84
85 tb[type] = attr;
86 return MNL_CB_OK;
87}
88
89static void
90nftnl_expr_socket_build(struct nlmsghdr *nlh, const struct nftnl_expr *e)
91{
92 struct nftnl_expr_socket *socket = nftnl_expr_data(e);
93
94 if (e->flags & (1 << NFTNL_EXPR_SOCKET_KEY))
95 mnl_attr_put_u32(nlh, NFTA_SOCKET_KEY, htonl(socket->key));
96 if (e->flags & (1 << NFTNL_EXPR_SOCKET_DREG))
97 mnl_attr_put_u32(nlh, NFTA_SOCKET_DREG, htonl(socket->dreg));
98 if (e->flags & (1 << NFTNL_EXPR_SOCKET_LEVEL))
99 mnl_attr_put_u32(nlh, NFTA_SOCKET_LEVEL, htonl(socket->level));
100}
101
102static int
103nftnl_expr_socket_parse(struct nftnl_expr *e, struct nlattr *attr)
104{
105 struct nftnl_expr_socket *socket = nftnl_expr_data(e);
106 struct nlattr *tb[NFTA_SOCKET_MAX+1] = {};
107
108 if (mnl_attr_parse_nested(attr, nftnl_expr_socket_cb, tb) < 0)
109 return -1;
110
111 if (tb[NFTA_SOCKET_KEY]) {
112 socket->key = ntohl(mnl_attr_get_u32(tb[NFTA_SOCKET_KEY]));
113 e->flags |= (1 << NFTNL_EXPR_SOCKET_KEY);
114 }
115 if (tb[NFTA_SOCKET_DREG]) {
116 socket->dreg = ntohl(mnl_attr_get_u32(tb[NFTA_SOCKET_DREG]));
117 e->flags |= (1 << NFTNL_EXPR_SOCKET_DREG);
118 }
119 if (tb[NFTA_SOCKET_LEVEL]) {
120 socket->level = ntohl(mnl_attr_get_u32(tb[NFTA_SOCKET_LEVEL]));
121 e->flags |= (1 << NFTNL_EXPR_SOCKET_LEVEL);
122 }
123
124 return 0;
125}
126
127static const char *socket_key2str_array[NFT_SOCKET_MAX + 1] = {
128 [NFT_SOCKET_TRANSPARENT] = "transparent",
129 [NFT_SOCKET_MARK] = "mark",
130 [NFT_SOCKET_WILDCARD] = "wildcard",
131 [NFT_SOCKET_CGROUPV2] = "cgroupv2",
132};
133
134static const char *socket_key2str(uint8_t key)
135{
136 if (key < NFT_SOCKET_MAX + 1)
137 return socket_key2str_array[key];
138
139 return "unknown";
140}
141
142static int
143nftnl_expr_socket_snprintf(char *buf, size_t len,
144 uint32_t flags, const struct nftnl_expr *e)
145{
146 struct nftnl_expr_socket *socket = nftnl_expr_data(e);
147
148 if (e->flags & (1 << NFTNL_EXPR_SOCKET_DREG)) {
149 return snprintf(buf, len, "load %s => reg %u ",
150 socket_key2str(socket->key), socket->dreg);
151 }
152 if (e->flags & (1 << NFTNL_EXPR_SOCKET_LEVEL))
153 return snprintf(buf, len, "level %u ", socket->level);
154
155 return 0;
156}
157
158static struct attr_policy socket_attr_policy[__NFTNL_EXPR_SOCKET_MAX] = {
159 [NFTNL_EXPR_SOCKET_KEY] = { .maxlen = sizeof(uint32_t) },
160 [NFTNL_EXPR_SOCKET_DREG] = { .maxlen = sizeof(uint32_t) },
161 [NFTNL_EXPR_SOCKET_LEVEL] = { .maxlen = sizeof(uint32_t) },
162};
163
164struct expr_ops expr_ops_socket = {
165 .name = "socket",
166 .alloc_len = sizeof(struct nftnl_expr_socket),
167 .nftnl_max_attr = __NFTNL_EXPR_SOCKET_MAX - 1,
168 .attr_policy = socket_attr_policy,
169 .set = nftnl_expr_socket_set,
170 .get = nftnl_expr_socket_get,
171 .parse = nftnl_expr_socket_parse,
172 .build = nftnl_expr_socket_build,
173 .output = nftnl_expr_socket_snprintf,
174};