libnftnl 1.2.8
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, data_len);
36 break;
37 case NFTNL_EXPR_DUP_SREG_DEV:
38 memcpy(&dup->sreg_dev, data, data_len);
39 break;
40 }
41 return 0;
42}
43
44static const void *nftnl_expr_dup_get(const struct nftnl_expr *e,
45 uint16_t type, uint32_t *data_len)
46{
47 struct nftnl_expr_dup *dup = nftnl_expr_data(e);
48
49 switch (type) {
50 case NFTNL_EXPR_DUP_SREG_ADDR:
51 *data_len = sizeof(dup->sreg_addr);
52 return &dup->sreg_addr;
53 case NFTNL_EXPR_DUP_SREG_DEV:
54 *data_len = sizeof(dup->sreg_dev);
55 return &dup->sreg_dev;
56 }
57 return NULL;
58}
59
60static int nftnl_expr_dup_cb(const struct nlattr *attr, void *data)
61{
62 const struct nlattr **tb = data;
63 int type = mnl_attr_get_type(attr);
64
65 if (mnl_attr_type_valid(attr, NFTA_DUP_MAX) < 0)
66 return MNL_CB_OK;
67
68 switch (type) {
69 case NFTA_DUP_SREG_ADDR:
70 case NFTA_DUP_SREG_DEV:
71 if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
72 abi_breakage();
73 break;
74 }
75
76 tb[type] = attr;
77 return MNL_CB_OK;
78}
79
80static void nftnl_expr_dup_build(struct nlmsghdr *nlh,
81 const struct nftnl_expr *e)
82{
83 struct nftnl_expr_dup *dup = nftnl_expr_data(e);
84
85 if (e->flags & (1 << NFTNL_EXPR_DUP_SREG_ADDR))
86 mnl_attr_put_u32(nlh, NFTA_DUP_SREG_ADDR, htonl(dup->sreg_addr));
87 if (e->flags & (1 << NFTNL_EXPR_DUP_SREG_DEV))
88 mnl_attr_put_u32(nlh, NFTA_DUP_SREG_DEV, htonl(dup->sreg_dev));
89}
90
91static int nftnl_expr_dup_parse(struct nftnl_expr *e, struct nlattr *attr)
92{
93 struct nftnl_expr_dup *dup = nftnl_expr_data(e);
94 struct nlattr *tb[NFTA_DUP_MAX + 1] = {};
95 int ret = 0;
96
97 if (mnl_attr_parse_nested(attr, nftnl_expr_dup_cb, tb) < 0)
98 return -1;
99
100 if (tb[NFTA_DUP_SREG_ADDR]) {
101 dup->sreg_addr = ntohl(mnl_attr_get_u32(tb[NFTA_DUP_SREG_ADDR]));
102 e->flags |= (1 << NFTNL_EXPR_DUP_SREG_ADDR);
103 }
104 if (tb[NFTA_DUP_SREG_DEV]) {
105 dup->sreg_dev = ntohl(mnl_attr_get_u32(tb[NFTA_DUP_SREG_DEV]));
106 e->flags |= (1 << NFTNL_EXPR_DUP_SREG_DEV);
107 }
108
109 return ret;
110}
111
112static int nftnl_expr_dup_snprintf(char *buf, size_t remain,
113 uint32_t flags, const struct nftnl_expr *e)
114{
115 struct nftnl_expr_dup *dup = nftnl_expr_data(e);
116 int offset = 0, ret;
117
118 if (e->flags & (1 << NFTNL_EXPR_DUP_SREG_ADDR)) {
119 ret = snprintf(buf + offset, remain, "sreg_addr %u ", dup->sreg_addr);
120 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
121 }
122
123 if (e->flags & (1 << NFTNL_EXPR_DUP_SREG_DEV)) {
124 ret = snprintf(buf + offset, remain, "sreg_dev %u ", dup->sreg_dev);
125 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
126 }
127
128 return offset;
129}
130
131static struct attr_policy dup_attr_policy[__NFTNL_EXPR_DUP_MAX] = {
132 [NFTNL_EXPR_DUP_SREG_ADDR] = { .maxlen = sizeof(uint32_t) },
133 [NFTNL_EXPR_DUP_SREG_DEV] = { .maxlen = sizeof(uint32_t) },
134};
135
136struct expr_ops expr_ops_dup = {
137 .name = "dup",
138 .alloc_len = sizeof(struct nftnl_expr_dup),
139 .nftnl_max_attr = __NFTNL_EXPR_DUP_MAX - 1,
140 .attr_policy = dup_attr_policy,
141 .set = nftnl_expr_dup_set,
142 .get = nftnl_expr_dup_get,
143 .parse = nftnl_expr_dup_parse,
144 .build = nftnl_expr_dup_build,
145 .output = nftnl_expr_dup_snprintf,
146};