libnftnl 1.2.6
osf.c
1#include <stdio.h>
2#include <stdint.h>
3#include <string.h>
4#include <arpa/inet.h>
5#include <errno.h>
6#include <linux/netfilter/nf_tables.h>
7
8#include "internal.h"
9#include <libmnl/libmnl.h>
10#include <libnftnl/expr.h>
11#include <libnftnl/rule.h>
12
13#define OSF_GENRE_SIZE 32
14
16 enum nft_registers dreg;
17 uint8_t ttl;
18 uint32_t flags;
19};
20
21static int nftnl_expr_osf_set(struct nftnl_expr *e, uint16_t type,
22 const void *data, uint32_t data_len)
23{
24 struct nftnl_expr_osf *osf = nftnl_expr_data(e);
25
26 switch(type) {
27 case NFTNL_EXPR_OSF_DREG:
28 memcpy(&osf->dreg, data, sizeof(osf->dreg));
29 break;
30 case NFTNL_EXPR_OSF_TTL:
31 memcpy(&osf->ttl, data, sizeof(osf->ttl));
32 break;
33 case NFTNL_EXPR_OSF_FLAGS:
34 memcpy(&osf->flags, data, sizeof(osf->flags));
35 break;
36 }
37 return 0;
38}
39
40static const void *
41nftnl_expr_osf_get(const struct nftnl_expr *e, uint16_t type,
42 uint32_t *data_len)
43{
44 struct nftnl_expr_osf *osf = nftnl_expr_data(e);
45
46 switch(type) {
47 case NFTNL_EXPR_OSF_DREG:
48 *data_len = sizeof(osf->dreg);
49 return &osf->dreg;
50 case NFTNL_EXPR_OSF_TTL:
51 *data_len = sizeof(osf->ttl);
52 return &osf->ttl;
53 case NFTNL_EXPR_OSF_FLAGS:
54 *data_len = sizeof(osf->flags);
55 return &osf->flags;
56 }
57 return NULL;
58}
59
60static int nftnl_expr_osf_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_OSF_MAX) < 0)
66 return MNL_CB_OK;
67
68 switch(type) {
69 case NFTNL_EXPR_OSF_DREG:
70 case NFTNL_EXPR_OSF_FLAGS:
71 if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
72 abi_breakage();
73 break;
74
75 case NFTNL_EXPR_OSF_TTL:
76 if (mnl_attr_validate(attr, MNL_TYPE_U8) < 0)
77 abi_breakage();
78 break;
79
80 }
81
82 tb[type] = attr;
83 return MNL_CB_OK;
84}
85
86static void
87nftnl_expr_osf_build(struct nlmsghdr *nlh, const struct nftnl_expr *e)
88{
89 struct nftnl_expr_osf *osf = nftnl_expr_data(e);
90
91 if (e->flags & (1 << NFTNL_EXPR_OSF_DREG))
92 mnl_attr_put_u32(nlh, NFTNL_EXPR_OSF_DREG, htonl(osf->dreg));
93 if (e->flags & (1 << NFTNL_EXPR_OSF_TTL))
94 mnl_attr_put_u8(nlh, NFTNL_EXPR_OSF_TTL, osf->ttl);
95 if (e->flags & (1 << NFTNL_EXPR_OSF_FLAGS))
96 if (osf->flags)
97 mnl_attr_put_u32(nlh, NFTNL_EXPR_OSF_FLAGS, htonl(osf->flags));
98}
99
100static int
101nftnl_expr_osf_parse(struct nftnl_expr *e, struct nlattr *attr)
102{
103 struct nftnl_expr_osf *osf = nftnl_expr_data(e);
104 struct nlattr *tb[NFTA_OSF_MAX + 1] = {};
105
106 if (mnl_attr_parse_nested(attr, nftnl_expr_osf_cb, tb) < 0)
107 return -1;
108
109 if (tb[NFTA_OSF_DREG]) {
110 osf->dreg = ntohl(mnl_attr_get_u32(tb[NFTA_OSF_DREG]));
111 e->flags |= (1 << NFTNL_EXPR_OSF_DREG);
112 }
113
114 if (tb[NFTA_OSF_TTL]) {
115 osf->ttl = mnl_attr_get_u8(tb[NFTA_OSF_TTL]);
116 e->flags |= (1 << NFTNL_EXPR_OSF_TTL);
117 }
118
119 if (tb[NFTA_OSF_FLAGS]) {
120 osf->flags = ntohl(mnl_attr_get_u32(tb[NFTA_OSF_FLAGS]));
121 e->flags |= (1 << NFTNL_EXPR_OSF_FLAGS);
122 }
123
124 return 0;
125}
126
127static int
128nftnl_expr_osf_snprintf(char *buf, size_t len,
129 uint32_t flags, const struct nftnl_expr *e)
130{
131 struct nftnl_expr_osf *osf = nftnl_expr_data(e);
132 int ret, offset = 0;
133
134 if (e->flags & (1 << NFTNL_EXPR_OSF_DREG)) {
135 ret = snprintf(buf, len, "dreg %u ", osf->dreg);
136 SNPRINTF_BUFFER_SIZE(ret, len, offset);
137 }
138
139 return offset;
140}
141
142struct expr_ops expr_ops_osf = {
143 .name = "osf",
144 .alloc_len = sizeof(struct nftnl_expr_osf),
145 .max_attr = NFTA_OSF_MAX,
146 .set = nftnl_expr_osf_set,
147 .get = nftnl_expr_osf_get,
148 .parse = nftnl_expr_osf_parse,
149 .build = nftnl_expr_osf_build,
150 .output = nftnl_expr_osf_snprintf,
151};