libnftnl 1.3.2
range.c
1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 * (C) 2016 by Pablo Neira Ayuso <pablo@netfilter.org>
4 */
5
6#include "internal.h"
7
8#include <stdio.h>
9#include <stdint.h>
10#include <string.h>
11#include <arpa/inet.h>
12#include <errno.h>
13
14#include <libmnl/libmnl.h>
15#include <linux/netfilter/nf_tables.h>
16#include <libnftnl/expr.h>
17#include <libnftnl/rule.h>
18
20 union nftnl_data_reg data_from;
21 union nftnl_data_reg data_to;
22 enum nft_registers sreg;
23 enum nft_range_ops op;
24};
25
26static int
27nftnl_expr_range_set(struct nftnl_expr *e, uint16_t type,
28 const void *data, uint32_t data_len, uint32_t byteorder)
29{
30 struct nftnl_expr_range *range = nftnl_expr_data(e);
31
32 switch(type) {
33 case NFTNL_EXPR_RANGE_SREG:
34 memcpy(&range->sreg, data, data_len);
35 break;
36 case NFTNL_EXPR_RANGE_OP:
37 memcpy(&range->op, data, data_len);
38 break;
39 case NFTNL_EXPR_RANGE_FROM_DATA:
40 return nftnl_data_cpy(&range->data_from, data,
41 data_len, byteorder, NULL);
42 case NFTNL_EXPR_RANGE_TO_DATA:
43 return nftnl_data_cpy(&range->data_to, data,
44 data_len, byteorder, NULL);
45 }
46 return 0;
47}
48
49static const void *nftnl_expr_range_get(const struct nftnl_expr *e,
50 uint16_t type, uint32_t *data_len)
51{
52 struct nftnl_expr_range *range = nftnl_expr_data(e);
53
54 switch(type) {
55 case NFTNL_EXPR_RANGE_SREG:
56 *data_len = sizeof(range->sreg);
57 return &range->sreg;
58 case NFTNL_EXPR_RANGE_OP:
59 *data_len = sizeof(range->op);
60 return &range->op;
61 case NFTNL_EXPR_RANGE_FROM_DATA:
62 *data_len = range->data_from.len;
63 return &range->data_from.val;
64 case NFTNL_EXPR_RANGE_TO_DATA:
65 *data_len = range->data_to.len;
66 return &range->data_to.val;
67 }
68 return NULL;
69}
70
71static int nftnl_expr_range_cb(const struct nlattr *attr, void *data)
72{
73 const struct nlattr **tb = data;
74 int type = mnl_attr_get_type(attr);
75
76 if (mnl_attr_type_valid(attr, NFTA_RANGE_MAX) < 0)
77 return MNL_CB_OK;
78
79 switch(type) {
80 case NFTA_RANGE_SREG:
81 case NFTA_RANGE_OP:
82 if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
83 abi_breakage();
84 break;
85 case NFTA_RANGE_FROM_DATA:
86 case NFTA_RANGE_TO_DATA:
87 if (mnl_attr_validate(attr, MNL_TYPE_BINARY) < 0)
88 abi_breakage();
89 break;
90 }
91
92 tb[type] = attr;
93 return MNL_CB_OK;
94}
95
96static void
97nftnl_expr_range_build(struct nlmsghdr *nlh, const struct nftnl_expr *e)
98{
99 struct nftnl_expr_range *range = nftnl_expr_data(e);
100
101 if (e->flags & (1 << NFTNL_EXPR_RANGE_SREG))
102 mnl_attr_put_u32(nlh, NFTA_RANGE_SREG, htonl(range->sreg));
103 if (e->flags & (1 << NFTNL_EXPR_RANGE_OP))
104 mnl_attr_put_u32(nlh, NFTA_RANGE_OP, htonl(range->op));
105 if (e->flags & (1 << NFTNL_EXPR_RANGE_FROM_DATA)) {
106 struct nlattr *nest;
107
108 nest = mnl_attr_nest_start(nlh, NFTA_RANGE_FROM_DATA);
109 mnl_attr_put(nlh, NFTA_DATA_VALUE, range->data_from.len,
110 range->data_from.val);
111 mnl_attr_nest_end(nlh, nest);
112 }
113 if (e->flags & (1 << NFTNL_EXPR_RANGE_TO_DATA)) {
114 struct nlattr *nest;
115
116 nest = mnl_attr_nest_start(nlh, NFTA_RANGE_TO_DATA);
117 mnl_attr_put(nlh, NFTA_DATA_VALUE, range->data_to.len,
118 range->data_to.val);
119 mnl_attr_nest_end(nlh, nest);
120 }
121}
122
123static int
124nftnl_expr_range_parse(struct nftnl_expr *e, struct nlattr *attr)
125{
126 struct nftnl_expr_range *range = nftnl_expr_data(e);
127 struct nlattr *tb[NFTA_RANGE_MAX+1] = {};
128 int ret = 0;
129
130 if (mnl_attr_parse_nested(attr, nftnl_expr_range_cb, tb) < 0)
131 return -1;
132
133 if (tb[NFTA_RANGE_SREG]) {
134 range->sreg = ntohl(mnl_attr_get_u32(tb[NFTA_RANGE_SREG]));
135 e->flags |= (1 << NFTA_RANGE_SREG);
136 }
137 if (tb[NFTA_RANGE_OP]) {
138 range->op = ntohl(mnl_attr_get_u32(tb[NFTA_RANGE_OP]));
139 e->flags |= (1 << NFTA_RANGE_OP);
140 }
141 if (tb[NFTA_RANGE_FROM_DATA]) {
142 ret = nftnl_parse_data(&range->data_from,
143 tb[NFTA_RANGE_FROM_DATA], NULL);
144 e->flags |= (1 << NFTA_RANGE_FROM_DATA);
145 }
146 if (tb[NFTA_RANGE_TO_DATA]) {
147 ret = nftnl_parse_data(&range->data_to,
148 tb[NFTA_RANGE_TO_DATA], NULL);
149 e->flags |= (1 << NFTA_RANGE_TO_DATA);
150 }
151
152 return ret;
153}
154
155static const char *expr_range_str[] = {
156 [NFT_RANGE_EQ] = "eq",
157 [NFT_RANGE_NEQ] = "neq",
158};
159
160static const char *range2str(uint32_t op)
161{
162 if (op > NFT_RANGE_NEQ)
163 return "unknown";
164
165 return expr_range_str[op];
166}
167
168static int nftnl_expr_range_snprintf(char *buf, size_t remain,
169 uint32_t flags, const struct nftnl_expr *e)
170{
171 struct nftnl_expr_range *range = nftnl_expr_data(e);
172 int offset = 0, ret;
173
174 ret = snprintf(buf, remain, "%s reg %u ",
175 range2str(range->op), range->sreg);
176 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
177
178 ret = nftnl_data_reg_snprintf(buf + offset, remain, &range->data_from,
179 0, DATA_VALUE);
180 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
181
182 ret = snprintf(buf + offset, remain, " ");
183 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
184
185 ret = nftnl_data_reg_snprintf(buf + offset, remain, &range->data_to,
186 0, DATA_VALUE);
187 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
188
189 ret = snprintf(buf + offset, remain, " ");
190 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
191
192 return offset;
193}
194
195static struct attr_policy range_attr_policy[__NFTNL_EXPR_RANGE_MAX] = {
196 [NFTNL_EXPR_RANGE_SREG] = { .maxlen = sizeof(uint32_t) },
197 [NFTNL_EXPR_RANGE_OP] = { .maxlen = sizeof(uint32_t) },
198 [NFTNL_EXPR_RANGE_FROM_DATA] = { .maxlen = NFT_DATA_VALUE_MAXLEN },
199 [NFTNL_EXPR_RANGE_TO_DATA] = { .maxlen = NFT_DATA_VALUE_MAXLEN },
200};
201
202struct expr_ops expr_ops_range = {
203 .name = "range",
204 .alloc_len = sizeof(struct nftnl_expr_range),
205 .nftnl_max_attr = __NFTNL_EXPR_RANGE_MAX - 1,
206 .attr_policy = range_attr_policy,
207 .set = nftnl_expr_range_set,
208 .get = nftnl_expr_range_get,
209 .parse = nftnl_expr_range_parse,
210 .build = nftnl_expr_range_build,
211 .output = nftnl_expr_range_snprintf,
212};