libnftnl 1.2.8
reject.c
1/*
2 * (C) 2013 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
25 uint32_t type;
26 uint8_t icmp_code;
27};
28
29static int nftnl_expr_reject_set(struct nftnl_expr *e, uint16_t type,
30 const void *data, uint32_t data_len)
31{
32 struct nftnl_expr_reject *reject = nftnl_expr_data(e);
33
34 switch(type) {
35 case NFTNL_EXPR_REJECT_TYPE:
36 memcpy(&reject->type, data, data_len);
37 break;
38 case NFTNL_EXPR_REJECT_CODE:
39 memcpy(&reject->icmp_code, data, data_len);
40 break;
41 }
42 return 0;
43}
44
45static const void *
46nftnl_expr_reject_get(const struct nftnl_expr *e, uint16_t type,
47 uint32_t *data_len)
48{
49 struct nftnl_expr_reject *reject = nftnl_expr_data(e);
50
51 switch(type) {
52 case NFTNL_EXPR_REJECT_TYPE:
53 *data_len = sizeof(reject->type);
54 return &reject->type;
55 case NFTNL_EXPR_REJECT_CODE:
56 *data_len = sizeof(reject->icmp_code);
57 return &reject->icmp_code;
58 }
59 return NULL;
60}
61
62static int nftnl_expr_reject_cb(const struct nlattr *attr, void *data)
63{
64 const struct nlattr **tb = data;
65 int type = mnl_attr_get_type(attr);
66
67 if (mnl_attr_type_valid(attr, NFTA_REJECT_MAX) < 0)
68 return MNL_CB_OK;
69
70 switch(type) {
71 case NFTA_REJECT_TYPE:
72 if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
73 abi_breakage();
74 break;
75 case NFTA_REJECT_ICMP_CODE:
76 if (mnl_attr_validate(attr, MNL_TYPE_U8) < 0)
77 abi_breakage();
78 break;
79 }
80
81 tb[type] = attr;
82 return MNL_CB_OK;
83}
84
85static void
86nftnl_expr_reject_build(struct nlmsghdr *nlh, const struct nftnl_expr *e)
87{
88 struct nftnl_expr_reject *reject = nftnl_expr_data(e);
89
90 if (e->flags & (1 << NFTNL_EXPR_REJECT_TYPE))
91 mnl_attr_put_u32(nlh, NFTA_REJECT_TYPE, htonl(reject->type));
92 if (e->flags & (1 << NFTNL_EXPR_REJECT_CODE))
93 mnl_attr_put_u8(nlh, NFTA_REJECT_ICMP_CODE, reject->icmp_code);
94}
95
96static int
97nftnl_expr_reject_parse(struct nftnl_expr *e, struct nlattr *attr)
98{
99 struct nftnl_expr_reject *reject = nftnl_expr_data(e);
100 struct nlattr *tb[NFTA_REJECT_MAX+1] = {};
101
102 if (mnl_attr_parse_nested(attr, nftnl_expr_reject_cb, tb) < 0)
103 return -1;
104
105 if (tb[NFTA_REJECT_TYPE]) {
106 reject->type = ntohl(mnl_attr_get_u32(tb[NFTA_REJECT_TYPE]));
107 e->flags |= (1 << NFTNL_EXPR_REJECT_TYPE);
108 }
109 if (tb[NFTA_REJECT_ICMP_CODE]) {
110 reject->icmp_code = mnl_attr_get_u8(tb[NFTA_REJECT_ICMP_CODE]);
111 e->flags |= (1 << NFTNL_EXPR_REJECT_CODE);
112 }
113
114 return 0;
115}
116
117static int
118nftnl_expr_reject_snprintf(char *buf, size_t len,
119 uint32_t flags, const struct nftnl_expr *e)
120{
121 struct nftnl_expr_reject *reject = nftnl_expr_data(e);
122
123 return snprintf(buf, len, "type %u code %u ",
124 reject->type, reject->icmp_code);
125}
126
127static struct attr_policy reject_attr_policy[__NFTNL_EXPR_REJECT_MAX] = {
128 [NFTNL_EXPR_REJECT_TYPE] = { .maxlen = sizeof(uint32_t) },
129 [NFTNL_EXPR_REJECT_CODE] = { .maxlen = sizeof(uint8_t) },
130};
131
132struct expr_ops expr_ops_reject = {
133 .name = "reject",
134 .alloc_len = sizeof(struct nftnl_expr_reject),
135 .nftnl_max_attr = __NFTNL_EXPR_REJECT_MAX - 1,
136 .attr_policy = reject_attr_policy,
137 .set = nftnl_expr_reject_set,
138 .get = nftnl_expr_reject_get,
139 .parse = nftnl_expr_reject_parse,
140 .build = nftnl_expr_reject_build,
141 .output = nftnl_expr_reject_snprintf,
142};