libnftnl 1.2.6
dup.c
1/*
2 * (C) 2015 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
10#include <stdio.h>
11#include <stdint.h>
12#include <string.h>
13#include <arpa/inet.h>
14#include <errno.h>
15#include "internal.h"
16#include <libmnl/libmnl.h>
17#include <linux/netfilter/nf_tables.h>
18#include <libnftnl/expr.h>
19#include <libnftnl/rule.h>
20#include "expr_ops.h"
21#include "data_reg.h"
22
24 enum nft_registers sreg_addr;
25 enum nft_registers sreg_dev;
26};
27
28static int nftnl_expr_dup_set(struct nftnl_expr *e, uint16_t type,
29 const void *data, uint32_t data_len)
30{
31 struct nftnl_expr_dup *dup = nftnl_expr_data(e);
32
33 switch (type) {
34 case NFTNL_EXPR_DUP_SREG_ADDR:
35 memcpy(&dup->sreg_addr, data, sizeof(dup->sreg_addr));
36 break;
37 case NFTNL_EXPR_DUP_SREG_DEV:
38 memcpy(&dup->sreg_dev, data, sizeof(dup->sreg_dev));
39 break;
40 default:
41 return -1;
42 }
43 return 0;
44}
45
46static const void *nftnl_expr_dup_get(const struct nftnl_expr *e,
47 uint16_t type, uint32_t *data_len)
48{
49 struct nftnl_expr_dup *dup = nftnl_expr_data(e);
50
51 switch (type) {
52 case NFTNL_EXPR_DUP_SREG_ADDR:
53 *data_len = sizeof(dup->sreg_addr);
54 return &dup->sreg_addr;
55 case NFTNL_EXPR_DUP_SREG_DEV:
56 *data_len = sizeof(dup->sreg_dev);
57 return &dup->sreg_dev;
58 }
59 return NULL;
60}
61
62static int nftnl_expr_dup_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_DUP_MAX) < 0)
68 return MNL_CB_OK;
69
70 switch (type) {
71 case NFTA_DUP_SREG_ADDR:
72 case NFTA_DUP_SREG_DEV:
73 if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
74 abi_breakage();
75 break;
76 }
77
78 tb[type] = attr;
79 return MNL_CB_OK;
80}
81
82static void nftnl_expr_dup_build(struct nlmsghdr *nlh,
83 const struct nftnl_expr *e)
84{
85 struct nftnl_expr_dup *dup = nftnl_expr_data(e);
86
87 if (e->flags & (1 << NFTNL_EXPR_DUP_SREG_ADDR))
88 mnl_attr_put_u32(nlh, NFTA_DUP_SREG_ADDR, htonl(dup->sreg_addr));
89 if (e->flags & (1 << NFTNL_EXPR_DUP_SREG_DEV))
90 mnl_attr_put_u32(nlh, NFTA_DUP_SREG_DEV, htonl(dup->sreg_dev));
91}
92
93static int nftnl_expr_dup_parse(struct nftnl_expr *e, struct nlattr *attr)
94{
95 struct nftnl_expr_dup *dup = nftnl_expr_data(e);
96 struct nlattr *tb[NFTA_DUP_MAX + 1] = {};
97 int ret = 0;
98
99 if (mnl_attr_parse_nested(attr, nftnl_expr_dup_cb, tb) < 0)
100 return -1;
101
102 if (tb[NFTA_DUP_SREG_ADDR]) {
103 dup->sreg_addr = ntohl(mnl_attr_get_u32(tb[NFTA_DUP_SREG_ADDR]));
104 e->flags |= (1 << NFTNL_EXPR_DUP_SREG_ADDR);
105 }
106 if (tb[NFTA_DUP_SREG_DEV]) {
107 dup->sreg_dev = ntohl(mnl_attr_get_u32(tb[NFTA_DUP_SREG_DEV]));
108 e->flags |= (1 << NFTNL_EXPR_DUP_SREG_DEV);
109 }
110
111 return ret;
112}
113
114static int nftnl_expr_dup_snprintf(char *buf, size_t remain,
115 uint32_t flags, const struct nftnl_expr *e)
116{
117 struct nftnl_expr_dup *dup = nftnl_expr_data(e);
118 int offset = 0, ret;
119
120 if (e->flags & (1 << NFTNL_EXPR_DUP_SREG_ADDR)) {
121 ret = snprintf(buf + offset, remain, "sreg_addr %u ", dup->sreg_addr);
122 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
123 }
124
125 if (e->flags & (1 << NFTNL_EXPR_DUP_SREG_DEV)) {
126 ret = snprintf(buf + offset, remain, "sreg_dev %u ", dup->sreg_dev);
127 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
128 }
129
130 return offset;
131}
132
133struct expr_ops expr_ops_dup = {
134 .name = "dup",
135 .alloc_len = sizeof(struct nftnl_expr_dup),
136 .max_attr = NFTA_DUP_MAX,
137 .set = nftnl_expr_dup_set,
138 .get = nftnl_expr_dup_get,
139 .parse = nftnl_expr_dup_parse,
140 .build = nftnl_expr_dup_build,
141 .output = nftnl_expr_dup_snprintf,
142};