libnftnl 1.2.6
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, sizeof(socket->key));
37 break;
38 case NFTNL_EXPR_SOCKET_DREG:
39 memcpy(&socket->dreg, data, sizeof(socket->dreg));
40 break;
41 case NFTNL_EXPR_SOCKET_LEVEL:
42 memcpy(&socket->level, data, sizeof(socket->level));
43 break;
44 default:
45 return -1;
46 }
47 return 0;
48}
49
50static const void *
51nftnl_expr_socket_get(const struct nftnl_expr *e, uint16_t type,
52 uint32_t *data_len)
53{
54 struct nftnl_expr_socket *socket = nftnl_expr_data(e);
55
56 switch (type) {
57 case NFTNL_EXPR_SOCKET_KEY:
58 *data_len = sizeof(socket->key);
59 return &socket->key;
60 case NFTNL_EXPR_SOCKET_DREG:
61 *data_len = sizeof(socket->dreg);
62 return &socket->dreg;
63 case NFTNL_EXPR_SOCKET_LEVEL:
64 *data_len = sizeof(socket->level);
65 return &socket->level;
66 }
67 return NULL;
68}
69
70static int nftnl_expr_socket_cb(const struct nlattr *attr, void *data)
71{
72 const struct nlattr **tb = data;
73 int type = mnl_attr_get_type(attr);
74
75 if (mnl_attr_type_valid(attr, NFTA_SOCKET_MAX) < 0)
76 return MNL_CB_OK;
77
78 switch (type) {
79 case NFTA_SOCKET_KEY:
80 case NFTA_SOCKET_DREG:
81 case NFTA_SOCKET_LEVEL:
82 if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
83 abi_breakage();
84 break;
85 }
86
87 tb[type] = attr;
88 return MNL_CB_OK;
89}
90
91static void
92nftnl_expr_socket_build(struct nlmsghdr *nlh, const struct nftnl_expr *e)
93{
94 struct nftnl_expr_socket *socket = nftnl_expr_data(e);
95
96 if (e->flags & (1 << NFTNL_EXPR_SOCKET_KEY))
97 mnl_attr_put_u32(nlh, NFTA_SOCKET_KEY, htonl(socket->key));
98 if (e->flags & (1 << NFTNL_EXPR_SOCKET_DREG))
99 mnl_attr_put_u32(nlh, NFTA_SOCKET_DREG, htonl(socket->dreg));
100 if (e->flags & (1 << NFTNL_EXPR_SOCKET_LEVEL))
101 mnl_attr_put_u32(nlh, NFTA_SOCKET_LEVEL, htonl(socket->level));
102}
103
104static int
105nftnl_expr_socket_parse(struct nftnl_expr *e, struct nlattr *attr)
106{
107 struct nftnl_expr_socket *socket = nftnl_expr_data(e);
108 struct nlattr *tb[NFTA_SOCKET_MAX+1] = {};
109
110 if (mnl_attr_parse_nested(attr, nftnl_expr_socket_cb, tb) < 0)
111 return -1;
112
113 if (tb[NFTA_SOCKET_KEY]) {
114 socket->key = ntohl(mnl_attr_get_u32(tb[NFTA_SOCKET_KEY]));
115 e->flags |= (1 << NFTNL_EXPR_SOCKET_KEY);
116 }
117 if (tb[NFTA_SOCKET_DREG]) {
118 socket->dreg = ntohl(mnl_attr_get_u32(tb[NFTA_SOCKET_DREG]));
119 e->flags |= (1 << NFTNL_EXPR_SOCKET_DREG);
120 }
121 if (tb[NFTA_SOCKET_LEVEL]) {
122 socket->level = ntohl(mnl_attr_get_u32(tb[NFTA_SOCKET_LEVEL]));
123 e->flags |= (1 << NFTNL_EXPR_SOCKET_LEVEL);
124 }
125
126 return 0;
127}
128
129static const char *socket_key2str_array[NFT_SOCKET_MAX + 1] = {
130 [NFT_SOCKET_TRANSPARENT] = "transparent",
131 [NFT_SOCKET_MARK] = "mark",
132 [NFT_SOCKET_WILDCARD] = "wildcard",
133 [NFT_SOCKET_CGROUPV2] = "cgroupv2",
134};
135
136static const char *socket_key2str(uint8_t key)
137{
138 if (key < NFT_SOCKET_MAX + 1)
139 return socket_key2str_array[key];
140
141 return "unknown";
142}
143
144static int
145nftnl_expr_socket_snprintf(char *buf, size_t len,
146 uint32_t flags, const struct nftnl_expr *e)
147{
148 struct nftnl_expr_socket *socket = nftnl_expr_data(e);
149
150 if (e->flags & (1 << NFTNL_EXPR_SOCKET_DREG)) {
151 return snprintf(buf, len, "load %s => reg %u ",
152 socket_key2str(socket->key), socket->dreg);
153 }
154 if (e->flags & (1 << NFTNL_EXPR_SOCKET_LEVEL))
155 return snprintf(buf, len, "level %u ", socket->level);
156
157 return 0;
158}
159
160struct expr_ops expr_ops_socket = {
161 .name = "socket",
162 .alloc_len = sizeof(struct nftnl_expr_socket),
163 .max_attr = NFTA_SOCKET_MAX,
164 .set = nftnl_expr_socket_set,
165 .get = nftnl_expr_socket_get,
166 .parse = nftnl_expr_socket_parse,
167 .build = nftnl_expr_socket_build,
168 .output = nftnl_expr_socket_snprintf,
169};