libnftnl 1.2.8
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, data_len);
39 break;
40 case NFTNL_EXPR_FIB_DREG:
41 memcpy(&fib->dreg, data, data_len);
42 break;
43 case NFTNL_EXPR_FIB_FLAGS:
44 memcpy(&fib->flags, data, data_len);
45 break;
46 }
47 return 0;
48}
49
50static const void *
51nftnl_expr_fib_get(const struct nftnl_expr *e, uint16_t result,
52 uint32_t *data_len)
53{
54 struct nftnl_expr_fib *fib = nftnl_expr_data(e);
55
56 switch (result) {
57 case NFTNL_EXPR_FIB_RESULT:
58 *data_len = sizeof(fib->result);
59 return &fib->result;
60 case NFTNL_EXPR_FIB_DREG:
61 *data_len = sizeof(fib->dreg);
62 return &fib->dreg;
63 case NFTNL_EXPR_FIB_FLAGS:
64 *data_len = sizeof(fib->flags);
65 return &fib->flags;
66 }
67 return NULL;
68}
69
70static int nftnl_expr_fib_cb(const struct nlattr *attr, void *data)
71{
72 const struct nlattr **tb = data;
73 int type = mnl_attr_get_type(attr);
74
75 if (mnl_attr_type_valid(attr, NFTA_FIB_MAX) < 0)
76 return MNL_CB_OK;
77
78 switch (type) {
79 case NFTA_FIB_RESULT:
80 case NFTA_FIB_DREG:
81 case NFTA_FIB_FLAGS:
82 if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
83 abi_breakage();
84 break;
85 }
86
87 tb[type] = attr;
88 return MNL_CB_OK;
89}
90
91static void
92nftnl_expr_fib_build(struct nlmsghdr *nlh, const struct nftnl_expr *e)
93{
94 struct nftnl_expr_fib *fib = nftnl_expr_data(e);
95
96 if (e->flags & (1 << NFTNL_EXPR_FIB_FLAGS))
97 mnl_attr_put_u32(nlh, NFTA_FIB_FLAGS, htonl(fib->flags));
98 if (e->flags & (1 << NFTNL_EXPR_FIB_RESULT))
99 mnl_attr_put_u32(nlh, NFTA_FIB_RESULT, htonl(fib->result));
100 if (e->flags & (1 << NFTNL_EXPR_FIB_DREG))
101 mnl_attr_put_u32(nlh, NFTA_FIB_DREG, htonl(fib->dreg));
102}
103
104static int
105nftnl_expr_fib_parse(struct nftnl_expr *e, struct nlattr *attr)
106{
107 struct nftnl_expr_fib *fib = nftnl_expr_data(e);
108 struct nlattr *tb[NFTA_FIB_MAX+1] = {};
109 int ret = 0;
110
111 if (mnl_attr_parse_nested(attr, nftnl_expr_fib_cb, tb) < 0)
112 return -1;
113
114 if (tb[NFTA_FIB_RESULT]) {
115 fib->result = ntohl(mnl_attr_get_u32(tb[NFTA_FIB_RESULT]));
116 e->flags |= (1 << NFTNL_EXPR_FIB_RESULT);
117 }
118 if (tb[NFTA_FIB_DREG]) {
119 fib->dreg = ntohl(mnl_attr_get_u32(tb[NFTA_FIB_DREG]));
120 e->flags |= (1 << NFTNL_EXPR_FIB_DREG);
121 }
122 if (tb[NFTA_FIB_FLAGS]) {
123 fib->flags = ntohl(mnl_attr_get_u32(tb[NFTA_FIB_FLAGS]));
124 e->flags |= (1 << NFTNL_EXPR_FIB_FLAGS);
125 }
126 return ret;
127}
128
129static const char *fib_type[NFT_FIB_RESULT_MAX + 1] = {
130 [NFT_FIB_RESULT_OIF] = "oif",
131 [NFT_FIB_RESULT_OIFNAME] = "oifname",
132 [NFT_FIB_RESULT_ADDRTYPE] = "type",
133};
134
135static const char *fib_type_str(enum nft_fib_result r)
136{
137 if (r <= NFT_FIB_RESULT_MAX)
138 return fib_type[r];
139
140 return "unknown";
141}
142
143static int
144nftnl_expr_fib_snprintf(char *buf, size_t remain,
145 uint32_t printflags, const struct nftnl_expr *e)
146{
147 struct nftnl_expr_fib *fib = nftnl_expr_data(e);
148 uint32_t flags = fib->flags & ~NFTA_FIB_F_PRESENT;
149 uint32_t present_flag = fib->flags & NFTA_FIB_F_PRESENT;
150 int offset = 0, ret, i;
151 static const struct {
152 int bit;
153 const char *name;
154 } tab[] = {
155 { NFTA_FIB_F_SADDR, "saddr" },
156 { NFTA_FIB_F_DADDR, "daddr" },
157 { NFTA_FIB_F_MARK, "mark" },
158 { NFTA_FIB_F_IIF, "iif" },
159 { NFTA_FIB_F_OIF, "oif" },
160 };
161
162 for (i = 0; i < (sizeof(tab) / sizeof(tab[0])); i++) {
163 if (flags & tab[i].bit) {
164 ret = snprintf(buf + offset, remain, "%s ",
165 tab[i].name);
166 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
167
168 flags &= ~tab[i].bit;
169 if (flags) {
170 ret = snprintf(buf + offset, remain, ". ");
171 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
172 }
173 }
174 }
175
176 if (flags) {
177 ret = snprintf(buf + offset, remain, "unknown 0x%" PRIx32,
178 flags);
179 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
180 }
181
182 ret = snprintf(buf + offset, remain, "%s%s => reg %d ",
183 fib_type_str(fib->result),
184 present_flag ? " present" : "",
185 fib->dreg);
186 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
187
188 return offset;
189}
190
191static struct attr_policy fib_attr_policy[__NFTNL_EXPR_FIB_MAX] = {
192 [NFTNL_EXPR_FIB_DREG] = { .maxlen = sizeof(uint32_t) },
193 [NFTNL_EXPR_FIB_RESULT] = { .maxlen = sizeof(uint32_t) },
194 [NFTNL_EXPR_FIB_FLAGS] = { .maxlen = sizeof(uint32_t) },
195};
196
197struct expr_ops expr_ops_fib = {
198 .name = "fib",
199 .alloc_len = sizeof(struct nftnl_expr_fib),
200 .nftnl_max_attr = __NFTNL_EXPR_FIB_MAX - 1,
201 .attr_policy = fib_attr_policy,
202 .set = nftnl_expr_fib_set,
203 .get = nftnl_expr_fib_get,
204 .parse = nftnl_expr_fib_parse,
205 .build = nftnl_expr_fib_build,
206 .output = nftnl_expr_fib_snprintf,
207};