13 #include <arpa/inet.h>
15 #include <libmnl/libmnl.h>
16 #include <linux/netfilter/nf_tables.h>
17 #include <libnftnl/expr.h>
18 #include <libnftnl/rule.h>
21 enum nft_registers sreg;
22 enum nft_registers sreg2;
23 enum nft_registers dreg;
24 enum nft_bitwise_ops op;
26 union nftnl_data_reg mask;
27 union nftnl_data_reg xor;
28 union nftnl_data_reg data;
32 nftnl_expr_bitwise_set(
struct nftnl_expr *e, uint16_t type,
33 const void *data, uint32_t data_len)
38 case NFTNL_EXPR_BITWISE_SREG:
39 memcpy(&bitwise->sreg, data, data_len);
41 case NFTNL_EXPR_BITWISE_SREG2:
42 memcpy(&bitwise->sreg2, data,
sizeof(bitwise->sreg2));
44 case NFTNL_EXPR_BITWISE_DREG:
45 memcpy(&bitwise->dreg, data, data_len);
47 case NFTNL_EXPR_BITWISE_OP:
48 memcpy(&bitwise->op, data, data_len);
50 case NFTNL_EXPR_BITWISE_LEN:
51 memcpy(&bitwise->len, data, data_len);
53 case NFTNL_EXPR_BITWISE_MASK:
54 return nftnl_data_cpy(&bitwise->mask, data, data_len);
55 case NFTNL_EXPR_BITWISE_XOR:
56 return nftnl_data_cpy(&bitwise->xor, data, data_len);
57 case NFTNL_EXPR_BITWISE_DATA:
58 return nftnl_data_cpy(&bitwise->data, data, data_len);
64 nftnl_expr_bitwise_get(
const struct nftnl_expr *e, uint16_t type,
70 case NFTNL_EXPR_BITWISE_SREG:
71 *data_len =
sizeof(bitwise->sreg);
72 return &bitwise->sreg;
73 case NFTNL_EXPR_BITWISE_SREG2:
74 *data_len =
sizeof(bitwise->sreg2);
75 return &bitwise->sreg2;
76 case NFTNL_EXPR_BITWISE_DREG:
77 *data_len =
sizeof(bitwise->dreg);
78 return &bitwise->dreg;
79 case NFTNL_EXPR_BITWISE_OP:
80 *data_len =
sizeof(bitwise->op);
82 case NFTNL_EXPR_BITWISE_LEN:
83 *data_len =
sizeof(bitwise->len);
85 case NFTNL_EXPR_BITWISE_MASK:
86 *data_len = bitwise->mask.len;
87 return &bitwise->mask.val;
88 case NFTNL_EXPR_BITWISE_XOR:
89 *data_len = bitwise->xor.len;
90 return &bitwise->xor.val;
91 case NFTNL_EXPR_BITWISE_DATA:
92 *data_len = bitwise->data.len;
93 return &bitwise->data.val;
98 static int nftnl_expr_bitwise_cb(
const struct nlattr *attr,
void *data)
100 const struct nlattr **tb = data;
101 int type = mnl_attr_get_type(attr);
103 if (mnl_attr_type_valid(attr, NFTA_BITWISE_MAX) < 0)
107 case NFTA_BITWISE_SREG:
108 case NFTA_BITWISE_SREG2:
109 case NFTA_BITWISE_DREG:
110 case NFTA_BITWISE_OP:
111 case NFTA_BITWISE_LEN:
112 if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
115 case NFTA_BITWISE_MASK:
116 case NFTA_BITWISE_XOR:
117 case NFTA_BITWISE_DATA:
118 if (mnl_attr_validate(attr, MNL_TYPE_BINARY) < 0)
128 nftnl_expr_bitwise_build(
struct nlmsghdr *nlh,
const struct nftnl_expr *e)
132 if (e->flags & (1 << NFTNL_EXPR_BITWISE_SREG))
133 mnl_attr_put_u32(nlh, NFTA_BITWISE_SREG, htonl(bitwise->sreg));
134 if (e->flags & (1 << NFTNL_EXPR_BITWISE_SREG2))
135 mnl_attr_put_u32(nlh, NFTA_BITWISE_SREG2, htonl(bitwise->sreg2));
136 if (e->flags & (1 << NFTNL_EXPR_BITWISE_DREG))
137 mnl_attr_put_u32(nlh, NFTA_BITWISE_DREG, htonl(bitwise->dreg));
138 if (e->flags & (1 << NFTNL_EXPR_BITWISE_OP))
139 mnl_attr_put_u32(nlh, NFTA_BITWISE_OP, htonl(bitwise->op));
140 if (e->flags & (1 << NFTNL_EXPR_BITWISE_LEN))
141 mnl_attr_put_u32(nlh, NFTA_BITWISE_LEN, htonl(bitwise->len));
142 if (e->flags & (1 << NFTNL_EXPR_BITWISE_MASK)) {
145 nest = mnl_attr_nest_start(nlh, NFTA_BITWISE_MASK);
146 mnl_attr_put(nlh, NFTA_DATA_VALUE, bitwise->mask.len,
148 mnl_attr_nest_end(nlh, nest);
150 if (e->flags & (1 << NFTNL_EXPR_BITWISE_XOR)) {
153 nest = mnl_attr_nest_start(nlh, NFTA_BITWISE_XOR);
154 mnl_attr_put(nlh, NFTA_DATA_VALUE, bitwise->xor.len,
156 mnl_attr_nest_end(nlh, nest);
158 if (e->flags & (1 << NFTNL_EXPR_BITWISE_DATA)) {
161 nest = mnl_attr_nest_start(nlh, NFTA_BITWISE_DATA);
162 mnl_attr_put(nlh, NFTA_DATA_VALUE, bitwise->data.len,
164 mnl_attr_nest_end(nlh, nest);
169 nftnl_expr_bitwise_parse(
struct nftnl_expr *e,
struct nlattr *attr)
172 struct nlattr *tb[NFTA_BITWISE_MAX+1] = {};
175 if (mnl_attr_parse_nested(attr, nftnl_expr_bitwise_cb, tb) < 0)
178 if (tb[NFTA_BITWISE_SREG]) {
179 bitwise->sreg = ntohl(mnl_attr_get_u32(tb[NFTA_BITWISE_SREG]));
180 e->flags |= (1 << NFTNL_EXPR_BITWISE_SREG);
182 if (tb[NFTA_BITWISE_SREG2]) {
183 bitwise->sreg2 = ntohl(mnl_attr_get_u32(tb[NFTA_BITWISE_SREG2]));
184 e->flags |= (1 << NFTNL_EXPR_BITWISE_SREG2);
186 if (tb[NFTA_BITWISE_DREG]) {
187 bitwise->dreg = ntohl(mnl_attr_get_u32(tb[NFTA_BITWISE_DREG]));
188 e->flags |= (1 << NFTNL_EXPR_BITWISE_DREG);
190 if (tb[NFTA_BITWISE_OP]) {
191 bitwise->op = ntohl(mnl_attr_get_u32(tb[NFTA_BITWISE_OP]));
192 e->flags |= (1 << NFTNL_EXPR_BITWISE_OP);
194 if (tb[NFTA_BITWISE_LEN]) {
195 bitwise->len = ntohl(mnl_attr_get_u32(tb[NFTA_BITWISE_LEN]));
196 e->flags |= (1 << NFTNL_EXPR_BITWISE_LEN);
198 if (tb[NFTA_BITWISE_MASK]) {
199 ret = nftnl_parse_data(&bitwise->mask, tb[NFTA_BITWISE_MASK], NULL);
200 e->flags |= (1 << NFTA_BITWISE_MASK);
202 if (tb[NFTA_BITWISE_XOR]) {
203 ret = nftnl_parse_data(&bitwise->xor, tb[NFTA_BITWISE_XOR], NULL);
204 e->flags |= (1 << NFTA_BITWISE_XOR);
206 if (tb[NFTA_BITWISE_DATA]) {
207 ret = nftnl_parse_data(&bitwise->data, tb[NFTA_BITWISE_DATA], NULL);
208 e->flags |= (1 << NFTNL_EXPR_BITWISE_DATA);
215 nftnl_expr_bitwise_snprintf_mask_xor(
char *buf,
size_t remain,
220 ret = snprintf(buf, remain,
"reg %u = ( reg %u & ",
221 bitwise->dreg, bitwise->sreg);
222 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
224 ret = nftnl_data_reg_snprintf(buf + offset, remain, &bitwise->mask,
226 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
228 ret = snprintf(buf + offset, remain,
") ^ ");
229 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
231 ret = nftnl_data_reg_snprintf(buf + offset, remain, &bitwise->xor,
233 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
239 nftnl_expr_bitwise_snprintf_shift(
char *buf,
size_t remain,
const char *op,
241 {
int offset = 0, ret;
243 ret = snprintf(buf, remain,
"reg %u = ( reg %u %s ",
244 bitwise->dreg, bitwise->sreg, op);
245 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
247 ret = nftnl_data_reg_snprintf(buf + offset, remain, &bitwise->data,
249 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
251 ret = snprintf(buf + offset, remain,
") ");
252 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
258 nftnl_expr_bitwise_snprintf_bool(
char *buf,
size_t remain,
const char *op,
259 const struct nftnl_expr *e,
264 ret = snprintf(buf, remain,
"reg %u = ( reg %u %s ",
265 bitwise->dreg, bitwise->sreg, op);
266 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
268 if (e->flags & (1 << NFTNL_EXPR_BITWISE_SREG2))
269 ret = snprintf(buf + offset, remain,
"reg %u ", bitwise->sreg2);
271 ret = nftnl_data_reg_snprintf(buf + offset, remain,
274 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
276 ret = snprintf(buf + offset, remain,
") ");
277 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
283 nftnl_expr_bitwise_snprintf(
char *buf,
size_t size,
284 uint32_t flags,
const struct nftnl_expr *e)
289 switch (bitwise->op) {
290 case NFT_BITWISE_MASK_XOR:
291 err = nftnl_expr_bitwise_snprintf_mask_xor(buf, size, bitwise);
293 case NFT_BITWISE_LSHIFT:
294 err = nftnl_expr_bitwise_snprintf_shift(buf, size,
"<<",
297 case NFT_BITWISE_RSHIFT:
298 err = nftnl_expr_bitwise_snprintf_shift(buf, size,
">>",
301 case NFT_BITWISE_AND:
302 err = nftnl_expr_bitwise_snprintf_bool(buf, size,
"&", e,
306 err = nftnl_expr_bitwise_snprintf_bool(buf, size,
"|", e,
309 case NFT_BITWISE_XOR:
310 err = nftnl_expr_bitwise_snprintf_bool(buf, size,
"^", e,
318 static struct attr_policy bitwise_attr_policy[__NFTNL_EXPR_BITWISE_MAX] = {
319 [NFTNL_EXPR_BITWISE_SREG] = { .maxlen =
sizeof(uint32_t) },
320 [NFTNL_EXPR_BITWISE_DREG] = { .maxlen =
sizeof(uint32_t) },
321 [NFTNL_EXPR_BITWISE_LEN] = { .maxlen =
sizeof(uint32_t) },
322 [NFTNL_EXPR_BITWISE_MASK] = { .maxlen = NFT_DATA_VALUE_MAXLEN },
323 [NFTNL_EXPR_BITWISE_XOR] = { .maxlen = NFT_DATA_VALUE_MAXLEN },
324 [NFTNL_EXPR_BITWISE_OP] = { .maxlen =
sizeof(uint32_t) },
325 [NFTNL_EXPR_BITWISE_DATA] = { .maxlen = NFT_DATA_VALUE_MAXLEN },
328 struct expr_ops expr_ops_bitwise = {
331 .nftnl_max_attr = __NFTNL_EXPR_BITWISE_MAX - 1,
332 .attr_policy = bitwise_attr_policy,
333 .set = nftnl_expr_bitwise_set,
334 .get = nftnl_expr_bitwise_get,
335 .parse = nftnl_expr_bitwise_parse,
336 .build = nftnl_expr_bitwise_build,
337 .output = nftnl_expr_bitwise_snprintf,