11 #include <linux/netfilter/nf_tables.h>
14 #include <libmnl/libmnl.h>
15 #include <libnftnl/expr.h>
16 #include <libnftnl/rule.h>
19 enum nft_hash_types type;
20 enum nft_registers sreg;
21 enum nft_registers dreg;
29 nftnl_expr_hash_set(
struct nftnl_expr *e, uint16_t type,
30 const void *data, uint32_t data_len)
34 case NFTNL_EXPR_HASH_SREG:
35 memcpy(&hash->sreg, data, data_len);
37 case NFTNL_EXPR_HASH_DREG:
38 memcpy(&hash->dreg, data, data_len);
40 case NFTNL_EXPR_HASH_LEN:
41 memcpy(&hash->len, data, data_len);
43 case NFTNL_EXPR_HASH_MODULUS:
44 memcpy(&hash->modulus, data, data_len);
46 case NFTNL_EXPR_HASH_SEED:
47 memcpy(&hash->seed, data, data_len);
49 case NFTNL_EXPR_HASH_OFFSET:
50 memcpy(&hash->offset, data, data_len);
52 case NFTNL_EXPR_HASH_TYPE:
53 memcpy(&hash->type, data, data_len);
62 nftnl_expr_hash_get(
const struct nftnl_expr *e, uint16_t type,
68 case NFTNL_EXPR_HASH_SREG:
69 *data_len =
sizeof(hash->sreg);
71 case NFTNL_EXPR_HASH_DREG:
72 *data_len =
sizeof(hash->dreg);
74 case NFTNL_EXPR_HASH_LEN:
75 *data_len =
sizeof(hash->len);
77 case NFTNL_EXPR_HASH_MODULUS:
78 *data_len =
sizeof(hash->modulus);
79 return &hash->modulus;
80 case NFTNL_EXPR_HASH_SEED:
81 *data_len =
sizeof(hash->seed);
83 case NFTNL_EXPR_HASH_OFFSET:
84 *data_len =
sizeof(hash->offset);
86 case NFTNL_EXPR_HASH_TYPE:
87 *data_len =
sizeof(hash->type);
93 static int nftnl_expr_hash_cb(
const struct nlattr *attr,
void *data)
95 const struct nlattr **tb = data;
96 int type = mnl_attr_get_type(attr);
98 if (mnl_attr_type_valid(attr, NFTA_HASH_MAX) < 0)
105 case NFTA_HASH_MODULUS:
107 case NFTA_HASH_OFFSET:
109 if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
119 nftnl_expr_hash_build(
struct nlmsghdr *nlh,
const struct nftnl_expr *e)
123 if (e->flags & (1 << NFTNL_EXPR_HASH_SREG))
124 mnl_attr_put_u32(nlh, NFTA_HASH_SREG, htonl(hash->sreg));
125 if (e->flags & (1 << NFTNL_EXPR_HASH_DREG))
126 mnl_attr_put_u32(nlh, NFTA_HASH_DREG, htonl(hash->dreg));
127 if (e->flags & (1 << NFTNL_EXPR_HASH_LEN))
128 mnl_attr_put_u32(nlh, NFTA_HASH_LEN, htonl(hash->len));
129 if (e->flags & (1 << NFTNL_EXPR_HASH_MODULUS))
130 mnl_attr_put_u32(nlh, NFTA_HASH_MODULUS, htonl(hash->modulus));
131 if (e->flags & (1 << NFTNL_EXPR_HASH_SEED))
132 mnl_attr_put_u32(nlh, NFTA_HASH_SEED, htonl(hash->seed));
133 if (e->flags & (1 << NFTNL_EXPR_HASH_OFFSET))
134 mnl_attr_put_u32(nlh, NFTA_HASH_OFFSET, htonl(hash->offset));
135 if (e->flags & (1 << NFTNL_EXPR_HASH_TYPE))
136 mnl_attr_put_u32(nlh, NFTA_HASH_TYPE, htonl(hash->type));
140 nftnl_expr_hash_parse(
struct nftnl_expr *e,
struct nlattr *attr)
143 struct nlattr *tb[NFTA_HASH_MAX+1] = {};
146 if (mnl_attr_parse_nested(attr, nftnl_expr_hash_cb, tb) < 0)
149 if (tb[NFTA_HASH_SREG]) {
150 hash->sreg = ntohl(mnl_attr_get_u32(tb[NFTA_HASH_SREG]));
151 e->flags |= (1 << NFTNL_EXPR_HASH_SREG);
153 if (tb[NFTA_HASH_DREG]) {
154 hash->dreg = ntohl(mnl_attr_get_u32(tb[NFTA_HASH_DREG]));
155 e->flags |= (1 << NFTNL_EXPR_HASH_DREG);
157 if (tb[NFTA_HASH_LEN]) {
158 hash->len = ntohl(mnl_attr_get_u32(tb[NFTA_HASH_LEN]));
159 e->flags |= (1 << NFTNL_EXPR_HASH_LEN);
161 if (tb[NFTA_HASH_MODULUS]) {
162 hash->modulus = ntohl(mnl_attr_get_u32(tb[NFTA_HASH_MODULUS]));
163 e->flags |= (1 << NFTNL_EXPR_HASH_MODULUS);
165 if (tb[NFTA_HASH_SEED]) {
166 hash->seed = ntohl(mnl_attr_get_u32(tb[NFTA_HASH_SEED]));
167 e->flags |= (1 << NFTNL_EXPR_HASH_SEED);
169 if (tb[NFTA_HASH_OFFSET]) {
170 hash->offset = ntohl(mnl_attr_get_u32(tb[NFTA_HASH_OFFSET]));
171 e->flags |= (1 << NFTNL_EXPR_HASH_OFFSET);
173 if (tb[NFTA_HASH_TYPE]) {
174 hash->type = ntohl(mnl_attr_get_u32(tb[NFTA_HASH_TYPE]));
175 e->flags |= (1 << NFTNL_EXPR_HASH_TYPE);
182 nftnl_expr_hash_snprintf(
char *buf,
size_t remain,
183 uint32_t flags,
const struct nftnl_expr *e)
188 switch (hash->type) {
191 snprintf(buf, remain,
"reg %u = symhash() %% mod %u ",
194 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
196 case NFT_HASH_JENKINS:
199 snprintf(buf, remain,
200 "reg %u = jhash(reg %u, %u, 0x%x) %% mod %u ",
201 hash->dreg, hash->sreg, hash->len, hash->seed,
203 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
208 ret = snprintf(buf + offset, remain,
"offset %u ",
210 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
216 static struct attr_policy hash_attr_policy[__NFTNL_EXPR_HASH_MAX] = {
217 [NFTNL_EXPR_HASH_SREG] = { .maxlen =
sizeof(uint32_t) },
218 [NFTNL_EXPR_HASH_DREG] = { .maxlen =
sizeof(uint32_t) },
219 [NFTNL_EXPR_HASH_LEN] = { .maxlen =
sizeof(uint32_t) },
220 [NFTNL_EXPR_HASH_MODULUS] = { .maxlen =
sizeof(uint32_t) },
221 [NFTNL_EXPR_HASH_SEED] = { .maxlen =
sizeof(uint32_t) },
222 [NFTNL_EXPR_HASH_OFFSET] = { .maxlen =
sizeof(uint32_t) },
223 [NFTNL_EXPR_HASH_TYPE] = { .maxlen =
sizeof(uint32_t) },
226 struct expr_ops expr_ops_hash = {
229 .nftnl_max_attr = __NFTNL_EXPR_HASH_MAX - 1,
230 .attr_policy = hash_attr_policy,
231 .set = nftnl_expr_hash_set,
232 .get = nftnl_expr_hash_get,
233 .parse = nftnl_expr_hash_parse,
234 .build = nftnl_expr_hash_build,
235 .output = nftnl_expr_hash_snprintf,