libnftnl 1.2.6
fib.c
1/*
2 * (C) 2016 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 <inttypes.h>
14#include <string.h>
15#include <arpa/inet.h>
16#include <errno.h>
17#include <linux/netfilter/nf_tables.h>
18
19#include "internal.h"
20#include <libmnl/libmnl.h>
21#include <libnftnl/expr.h>
22#include <libnftnl/rule.h>
23
25 uint32_t flags;
26 uint32_t result;
27 enum nft_registers dreg;
28};
29
30static int
31nftnl_expr_fib_set(struct nftnl_expr *e, uint16_t result,
32 const void *data, uint32_t data_len)
33{
34 struct nftnl_expr_fib *fib = nftnl_expr_data(e);
35
36 switch (result) {
37 case NFTNL_EXPR_FIB_RESULT:
38 memcpy(&fib->result, data, sizeof(fib->result));
39 break;
40 case NFTNL_EXPR_FIB_DREG:
41 memcpy(&fib->dreg, data, sizeof(fib->dreg));
42 break;
43 case NFTNL_EXPR_FIB_FLAGS:
44 memcpy(&fib->flags, data, sizeof(fib->flags));
45 break;
46 default:
47 return -1;
48 }
49 return 0;
50}
51
52static const void *
53nftnl_expr_fib_get(const struct nftnl_expr *e, uint16_t result,
54 uint32_t *data_len)
55{
56 struct nftnl_expr_fib *fib = nftnl_expr_data(e);
57
58 switch (result) {
59 case NFTNL_EXPR_FIB_RESULT:
60 *data_len = sizeof(fib->result);
61 return &fib->result;
62 case NFTNL_EXPR_FIB_DREG:
63 *data_len = sizeof(fib->dreg);
64 return &fib->dreg;
65 case NFTNL_EXPR_FIB_FLAGS:
66 *data_len = sizeof(fib->flags);
67 return &fib->flags;
68 }
69 return NULL;
70}
71
72static int nftnl_expr_fib_cb(const struct nlattr *attr, void *data)
73{
74 const struct nlattr **tb = data;
75 int type = mnl_attr_get_type(attr);
76
77 if (mnl_attr_type_valid(attr, NFTA_FIB_MAX) < 0)
78 return MNL_CB_OK;
79
80 switch (type) {
81 case NFTA_FIB_RESULT:
82 case NFTA_FIB_DREG:
83 case NFTA_FIB_FLAGS:
84 if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
85 abi_breakage();
86 break;
87 }
88
89 tb[type] = attr;
90 return MNL_CB_OK;
91}
92
93static void
94nftnl_expr_fib_build(struct nlmsghdr *nlh, const struct nftnl_expr *e)
95{
96 struct nftnl_expr_fib *fib = nftnl_expr_data(e);
97
98 if (e->flags & (1 << NFTNL_EXPR_FIB_FLAGS))
99 mnl_attr_put_u32(nlh, NFTA_FIB_FLAGS, htonl(fib->flags));
100 if (e->flags & (1 << NFTNL_EXPR_FIB_RESULT))
101 mnl_attr_put_u32(nlh, NFTA_FIB_RESULT, htonl(fib->result));
102 if (e->flags & (1 << NFTNL_EXPR_FIB_DREG))
103 mnl_attr_put_u32(nlh, NFTA_FIB_DREG, htonl(fib->dreg));
104}
105
106static int
107nftnl_expr_fib_parse(struct nftnl_expr *e, struct nlattr *attr)
108{
109 struct nftnl_expr_fib *fib = nftnl_expr_data(e);
110 struct nlattr *tb[NFTA_FIB_MAX+1] = {};
111 int ret = 0;
112
113 if (mnl_attr_parse_nested(attr, nftnl_expr_fib_cb, tb) < 0)
114 return -1;
115
116 if (tb[NFTA_FIB_RESULT]) {
117 fib->result = ntohl(mnl_attr_get_u32(tb[NFTA_FIB_RESULT]));
118 e->flags |= (1 << NFTNL_EXPR_FIB_RESULT);
119 }
120 if (tb[NFTA_FIB_DREG]) {
121 fib->dreg = ntohl(mnl_attr_get_u32(tb[NFTA_FIB_DREG]));
122 e->flags |= (1 << NFTNL_EXPR_FIB_DREG);
123 }
124 if (tb[NFTA_FIB_FLAGS]) {
125 fib->flags = ntohl(mnl_attr_get_u32(tb[NFTA_FIB_FLAGS]));
126 e->flags |= (1 << NFTNL_EXPR_FIB_FLAGS);
127 }
128 return ret;
129}
130
131static const char *fib_type[NFT_FIB_RESULT_MAX + 1] = {
132 [NFT_FIB_RESULT_OIF] = "oif",
133 [NFT_FIB_RESULT_OIFNAME] = "oifname",
134 [NFT_FIB_RESULT_ADDRTYPE] = "type",
135};
136
137static const char *fib_type_str(enum nft_fib_result r)
138{
139 if (r <= NFT_FIB_RESULT_MAX)
140 return fib_type[r];
141
142 return "unknown";
143}
144
145static int
146nftnl_expr_fib_snprintf(char *buf, size_t remain,
147 uint32_t printflags, const struct nftnl_expr *e)
148{
149 struct nftnl_expr_fib *fib = nftnl_expr_data(e);
150 uint32_t flags = fib->flags & ~NFTA_FIB_F_PRESENT;
151 uint32_t present_flag = fib->flags & NFTA_FIB_F_PRESENT;
152 int offset = 0, ret, i;
153 static const struct {
154 int bit;
155 const char *name;
156 } tab[] = {
157 { NFTA_FIB_F_SADDR, "saddr" },
158 { NFTA_FIB_F_DADDR, "daddr" },
159 { NFTA_FIB_F_MARK, "mark" },
160 { NFTA_FIB_F_IIF, "iif" },
161 { NFTA_FIB_F_OIF, "oif" },
162 };
163
164 for (i = 0; i < (sizeof(tab) / sizeof(tab[0])); i++) {
165 if (flags & tab[i].bit) {
166 ret = snprintf(buf + offset, remain, "%s ",
167 tab[i].name);
168 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
169
170 flags &= ~tab[i].bit;
171 if (flags) {
172 ret = snprintf(buf + offset, remain, ". ");
173 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
174 }
175 }
176 }
177
178 if (flags) {
179 ret = snprintf(buf + offset, remain, "unknown 0x%" PRIx32,
180 flags);
181 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
182 }
183
184 ret = snprintf(buf + offset, remain, "%s%s => reg %d ",
185 fib_type_str(fib->result),
186 present_flag ? " present" : "",
187 fib->dreg);
188 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
189
190 return offset;
191}
192
193struct expr_ops expr_ops_fib = {
194 .name = "fib",
195 .alloc_len = sizeof(struct nftnl_expr_fib),
196 .max_attr = NFTA_FIB_MAX,
197 .set = nftnl_expr_fib_set,
198 .get = nftnl_expr_fib_get,
199 .parse = nftnl_expr_fib_parse,
200 .build = nftnl_expr_fib_build,
201 .output = nftnl_expr_fib_snprintf,
202};