libnftnl 1.2.6
ct_helper.c
1/*
2 * (C) 2017 Red Hat GmbH
3 * Author: Florian Westphal <fw@strlen.de>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published
7 * by the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 */
10
11#include <stdio.h>
12#include <stdint.h>
13#include <arpa/inet.h>
14#include <errno.h>
15#include <inttypes.h>
16
17#include <linux/netfilter/nf_tables.h>
18
19#include "internal.h"
20#include <libmnl/libmnl.h>
21#include <libnftnl/object.h>
22
23#include "obj.h"
24
25static int nftnl_obj_ct_helper_set(struct nftnl_obj *e, uint16_t type,
26 const void *data, uint32_t data_len)
27{
28 struct nftnl_obj_ct_helper *helper = nftnl_obj_data(e);
29
30 switch (type) {
31 case NFTNL_OBJ_CT_HELPER_NAME:
32 snprintf(helper->name, sizeof(helper->name), "%s", (const char *)data);
33 break;
34 case NFTNL_OBJ_CT_HELPER_L3PROTO:
35 memcpy(&helper->l3proto, data, sizeof(helper->l3proto));
36 break;
37 case NFTNL_OBJ_CT_HELPER_L4PROTO:
38 memcpy(&helper->l4proto, data, sizeof(helper->l4proto));
39 break;
40 default:
41 return -1;
42 }
43 return 0;
44}
45
46static const void *nftnl_obj_ct_helper_get(const struct nftnl_obj *e,
47 uint16_t type, uint32_t *data_len)
48{
49 struct nftnl_obj_ct_helper *helper = nftnl_obj_data(e);
50
51 switch (type) {
52 case NFTNL_OBJ_CT_HELPER_NAME:
53 *data_len = strlen(helper->name);
54 return helper->name;
55 case NFTNL_OBJ_CT_HELPER_L3PROTO:
56 *data_len = sizeof(helper->l3proto);
57 return &helper->l3proto;
58 case NFTNL_OBJ_CT_HELPER_L4PROTO:
59 *data_len = sizeof(helper->l4proto);
60 return &helper->l4proto;
61 }
62 return NULL;
63}
64
65static int nftnl_obj_ct_helper_cb(const struct nlattr *attr, void *data)
66{
67 const struct nftnl_obj_ct_helper *helper = NULL;
68 int type = mnl_attr_get_type(attr);
69 const struct nlattr **tb = data;
70
71 if (mnl_attr_type_valid(attr, NFTA_CT_HELPER_MAX) < 0)
72 return MNL_CB_OK;
73
74 switch (type) {
75 case NFTA_CT_HELPER_NAME:
76 if (mnl_attr_validate(attr, MNL_TYPE_STRING) < 0)
77 abi_breakage();
78 if (mnl_attr_get_payload_len(attr) >= sizeof(helper->name))
79 abi_breakage();
80 break;
81 case NFTA_CT_HELPER_L3PROTO:
82 if (mnl_attr_validate(attr, MNL_TYPE_U16) < 0)
83 abi_breakage();
84 break;
85 case NFTA_CT_HELPER_L4PROTO:
86 if (mnl_attr_validate(attr, MNL_TYPE_U8) < 0)
87 abi_breakage();
88 break;
89 }
90
91 tb[type] = attr;
92 return MNL_CB_OK;
93}
94
95static void
96nftnl_obj_ct_helper_build(struct nlmsghdr *nlh, const struct nftnl_obj *e)
97{
98 struct nftnl_obj_ct_helper *helper = nftnl_obj_data(e);
99
100 if (e->flags & (1 << NFTNL_OBJ_CT_HELPER_NAME))
101 mnl_attr_put_str(nlh, NFTA_CT_HELPER_NAME, helper->name);
102 if (e->flags & (1 << NFTNL_OBJ_CT_HELPER_L3PROTO))
103 mnl_attr_put_u16(nlh, NFTA_CT_HELPER_L3PROTO, htons(helper->l3proto));
104 if (e->flags & (1 << NFTNL_OBJ_CT_HELPER_L4PROTO))
105 mnl_attr_put_u8(nlh, NFTA_CT_HELPER_L4PROTO, helper->l4proto);
106}
107
108static int
109nftnl_obj_ct_helper_parse(struct nftnl_obj *e, struct nlattr *attr)
110{
111 struct nftnl_obj_ct_helper *helper = nftnl_obj_data(e);
112 struct nlattr *tb[NFTA_CT_HELPER_MAX + 1] = {};
113
114 if (mnl_attr_parse_nested(attr, nftnl_obj_ct_helper_cb, tb) < 0)
115 return -1;
116
117 if (tb[NFTA_CT_HELPER_NAME]) {
118 snprintf(helper->name, sizeof(helper->name), "%s",
119 mnl_attr_get_str(tb[NFTA_CT_HELPER_NAME]));
120 e->flags |= (1 << NFTNL_OBJ_CT_HELPER_NAME);
121 }
122 if (tb[NFTA_CT_HELPER_L3PROTO]) {
123 helper->l3proto = ntohs(mnl_attr_get_u16(tb[NFTA_CT_HELPER_L3PROTO]));
124 e->flags |= (1 << NFTNL_OBJ_CT_HELPER_L3PROTO);
125 }
126 if (tb[NFTA_CT_HELPER_L4PROTO]) {
127 helper->l4proto = mnl_attr_get_u8(tb[NFTA_CT_HELPER_L4PROTO]);
128 e->flags |= (1 << NFTNL_OBJ_CT_HELPER_L4PROTO);
129 }
130
131 return 0;
132}
133
134static int nftnl_obj_ct_helper_snprintf(char *buf, size_t len,
135 uint32_t flags,
136 const struct nftnl_obj *e)
137{
138 struct nftnl_obj_ct_helper *helper = nftnl_obj_data(e);
139
140 return snprintf(buf, len, "name %s family %d protocol %d ",
141 helper->name, helper->l3proto, helper->l4proto);
142}
143
144struct obj_ops obj_ops_ct_helper = {
145 .name = "ct_helper",
146 .type = NFT_OBJECT_CT_HELPER,
147 .alloc_len = sizeof(struct nftnl_obj_ct_helper),
148 .max_attr = NFTA_CT_HELPER_MAX,
149 .set = nftnl_obj_ct_helper_set,
150 .get = nftnl_obj_ct_helper_get,
151 .parse = nftnl_obj_ct_helper_parse,
152 .build = nftnl_obj_ct_helper_build,
153 .output = nftnl_obj_ct_helper_snprintf,
154};