libnftnl 1.2.6
obj/synproxy.c
1#include <stdio.h>
2#include <stdint.h>
3#include <arpa/inet.h>
4#include <errno.h>
5#include <inttypes.h>
6
7#include <linux/netfilter/nf_tables.h>
8
9#include "internal.h"
10#include <libmnl/libmnl.h>
11#include <libnftnl/object.h>
12
13#include "obj.h"
14
15static int nftnl_obj_synproxy_set(struct nftnl_obj *e, uint16_t type,
16 const void *data, uint32_t data_len)
17{
18 struct nftnl_obj_synproxy *synproxy = nftnl_obj_data(e);
19
20 switch (type) {
21 case NFTNL_OBJ_SYNPROXY_MSS:
22 synproxy->mss = *((uint16_t *)data);
23 break;
24 case NFTNL_OBJ_SYNPROXY_WSCALE:
25 synproxy->wscale = *((uint8_t *)data);
26 break;
27 case NFTNL_OBJ_SYNPROXY_FLAGS:
28 synproxy->flags = *((uint32_t *)data);
29 break;
30 default:
31 return -1;
32 }
33 return 0;
34}
35
36static const void *nftnl_obj_synproxy_get(const struct nftnl_obj *e,
37 uint16_t type, uint32_t *data_len)
38{
39 struct nftnl_obj_synproxy *synproxy = nftnl_obj_data(e);
40
41 switch (type) {
42 case NFTNL_OBJ_SYNPROXY_MSS:
43 *data_len = sizeof(synproxy->mss);
44 return &synproxy->mss;
45 case NFTNL_OBJ_SYNPROXY_WSCALE:
46 *data_len = sizeof(synproxy->wscale);
47 return &synproxy->wscale;
48 case NFTNL_OBJ_SYNPROXY_FLAGS:
49 *data_len = sizeof(synproxy->flags);
50 return &synproxy->flags;
51 }
52 return NULL;
53}
54
55static int nftnl_obj_synproxy_cb(const struct nlattr *attr, void *data)
56{
57 int type = mnl_attr_get_type(attr);
58 const struct nlattr **tb = data;
59
60 if (mnl_attr_type_valid(attr, NFTA_SYNPROXY_MAX) < 0)
61 return MNL_CB_OK;
62
63 switch (type) {
64 case NFTA_SYNPROXY_MSS:
65 if (mnl_attr_validate(attr, MNL_TYPE_U16) < 0)
66 abi_breakage();
67 break;
68 case NFTA_SYNPROXY_WSCALE:
69 if (mnl_attr_validate(attr, MNL_TYPE_U8) < 0)
70 abi_breakage();
71 break;
72 case NFTA_SYNPROXY_FLAGS:
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_obj_synproxy_build(struct nlmsghdr *nlh,
83 const struct nftnl_obj *e)
84{
85 struct nftnl_obj_synproxy *synproxy = nftnl_obj_data(e);
86
87 if (e->flags & (1 << NFTNL_OBJ_SYNPROXY_MSS))
88 mnl_attr_put_u16(nlh, NFTA_SYNPROXY_MSS, htons(synproxy->mss));
89 if (e->flags & (1 << NFTNL_OBJ_SYNPROXY_WSCALE))
90 mnl_attr_put_u8(nlh, NFTA_SYNPROXY_WSCALE, synproxy->wscale);
91 if (e->flags & (1 << NFTNL_OBJ_SYNPROXY_FLAGS))
92 mnl_attr_put_u32(nlh, NFTA_SYNPROXY_FLAGS,
93 htonl(synproxy->flags));
94}
95
96static int nftnl_obj_synproxy_parse(struct nftnl_obj *e, struct nlattr *attr)
97{
98 struct nftnl_obj_synproxy *synproxy = nftnl_obj_data(e);
99 struct nlattr *tb[NFTA_SYNPROXY_MAX + 1] = {};
100
101 if (mnl_attr_parse_nested(attr, nftnl_obj_synproxy_cb, tb) < 0)
102 return -1;
103
104 if (tb[NFTA_SYNPROXY_MSS]) {
105 synproxy->mss = ntohs(mnl_attr_get_u16(tb[NFTA_SYNPROXY_MSS]));
106 e->flags |= (1 << NFTNL_OBJ_SYNPROXY_MSS);
107 }
108 if (tb[NFTA_SYNPROXY_WSCALE]) {
109 synproxy->wscale = mnl_attr_get_u8(tb[NFTA_SYNPROXY_WSCALE]);
110 e->flags |= (1 << NFTNL_OBJ_SYNPROXY_WSCALE);
111 }
112 if (tb[NFTA_SYNPROXY_FLAGS]) {
113 synproxy->flags = ntohl(mnl_attr_get_u32(tb[NFTA_SYNPROXY_FLAGS]));
114 e->flags |= (1 << NFTNL_OBJ_SYNPROXY_FLAGS);
115 }
116
117 return 0;
118}
119
120static int nftnl_obj_synproxy_snprintf(char *buf, size_t len,
121 uint32_t flags,
122 const struct nftnl_obj *e)
123{
124 struct nftnl_obj_synproxy *synproxy = nftnl_obj_data(e);
125 int ret, offset = 0;
126
127 if (e->flags & (1 << NFTNL_OBJ_SYNPROXY_MSS) &&
128 e->flags & (1 << NFTNL_OBJ_SYNPROXY_WSCALE)) {
129 ret = snprintf(buf, len, "mss %u wscale %u ", synproxy->mss,
130 synproxy->wscale);
131 SNPRINTF_BUFFER_SIZE(ret, len, offset);
132 }
133
134 return offset;
135}
136
137struct obj_ops obj_ops_synproxy = {
138 .name = "synproxy",
139 .type = NFT_OBJECT_SYNPROXY,
140 .alloc_len = sizeof(struct nftnl_obj_synproxy),
141 .max_attr = NFTA_SYNPROXY_MAX,
142 .set = nftnl_obj_synproxy_set,
143 .get = nftnl_obj_synproxy_get,
144 .parse = nftnl_obj_synproxy_parse,
145 .build = nftnl_obj_synproxy_build,
146 .output = nftnl_obj_synproxy_snprintf,
147};