libnftnl 1.2.6
flow_offload.c
1#include "internal.h"
2
3#include <stdio.h>
4#include <stdint.h>
5#include <string.h> /* for memcpy */
6#include <arpa/inet.h>
7#include <errno.h>
8#include <libmnl/libmnl.h>
9#include <linux/netfilter/nf_tables.h>
10#include <libnftnl/rule.h>
11#include <libnftnl/expr.h>
12
14 char *table_name;
15};
16
17static int nftnl_expr_flow_set(struct nftnl_expr *e, uint16_t type,
18 const void *data, uint32_t data_len)
19{
20 struct nftnl_expr_flow *flow = nftnl_expr_data(e);
21
22 switch (type) {
23 case NFTNL_EXPR_FLOW_TABLE_NAME:
24 flow->table_name = strdup((const char *)data);
25 if (!flow->table_name)
26 return -1;
27 break;
28 default:
29 return -1;
30 }
31 return 0;
32}
33
34static const void *nftnl_expr_flow_get(const struct nftnl_expr *e,
35 uint16_t type, uint32_t *data_len)
36{
37 struct nftnl_expr_flow *flow = nftnl_expr_data(e);
38
39 switch(type) {
40 case NFTNL_EXPR_FLOW_TABLE_NAME:
41 *data_len = strlen(flow->table_name) + 1;
42 return flow->table_name;
43 }
44 return NULL;
45}
46
47static int nftnl_expr_flow_cb(const struct nlattr *attr, void *data)
48{
49 const struct nlattr **tb = data;
50 int type = mnl_attr_get_type(attr);
51
52 if (mnl_attr_type_valid(attr, NFTA_FLOW_MAX) < 0)
53 return MNL_CB_OK;
54
55 switch(type) {
56 case NFTA_FLOW_TABLE_NAME:
57 if (mnl_attr_validate(attr, MNL_TYPE_STRING) < 0)
58 abi_breakage();
59 break;
60 }
61
62 tb[type] = attr;
63 return MNL_CB_OK;
64}
65
66static void nftnl_expr_flow_build(struct nlmsghdr *nlh,
67 const struct nftnl_expr *e)
68{
69 struct nftnl_expr_flow *flow = nftnl_expr_data(e);
70
71 if (e->flags & (1 << NFTNL_EXPR_FLOW_TABLE_NAME))
72 mnl_attr_put_strz(nlh, NFTA_FLOW_TABLE_NAME, flow->table_name);
73}
74
75static int nftnl_expr_flow_parse(struct nftnl_expr *e, struct nlattr *attr)
76{
77 struct nftnl_expr_flow *flow = nftnl_expr_data(e);
78 struct nlattr *tb[NFTA_FLOW_MAX+1] = {};
79 int ret = 0;
80
81 if (mnl_attr_parse_nested(attr, nftnl_expr_flow_cb, tb) < 0)
82 return -1;
83
84 if (tb[NFTA_FLOW_TABLE_NAME]) {
85 flow->table_name =
86 strdup(mnl_attr_get_str(tb[NFTA_FLOW_TABLE_NAME]));
87 if (!flow->table_name)
88 return -1;
89 e->flags |= (1 << NFTNL_EXPR_FLOW_TABLE_NAME);
90 }
91
92 return ret;
93}
94
95static int nftnl_expr_flow_snprintf(char *buf, size_t remain,
96 uint32_t flags, const struct nftnl_expr *e)
97{
98 struct nftnl_expr_flow *l = nftnl_expr_data(e);
99 int offset = 0, ret;
100
101 ret = snprintf(buf, remain, "flowtable %s ", l->table_name);
102 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
103
104 return offset;
105}
106
107static void nftnl_expr_flow_free(const struct nftnl_expr *e)
108{
109 struct nftnl_expr_flow *flow = nftnl_expr_data(e);
110
111 xfree(flow->table_name);
112}
113
114struct expr_ops expr_ops_flow = {
115 .name = "flow_offload",
116 .alloc_len = sizeof(struct nftnl_expr_flow),
117 .max_attr = NFTA_FLOW_MAX,
118 .free = nftnl_expr_flow_free,
119 .set = nftnl_expr_flow_set,
120 .get = nftnl_expr_flow_get,
121 .parse = nftnl_expr_flow_parse,
122 .build = nftnl_expr_flow_build,
123 .output = nftnl_expr_flow_snprintf,
124};