18 #include <arpa/inet.h>
20 #include <libmnl/libmnl.h>
22 #include <linux/netfilter/nf_tables.h>
24 #include <libnftnl/expr.h>
25 #include <libnftnl/rule.h>
28 enum nft_registers dreg;
29 enum nft_payload_bases base;
35 nftnl_expr_payload_set(
struct nftnl_expr *e, uint16_t type,
36 const void *data, uint32_t data_len)
41 case NFTNL_EXPR_PAYLOAD_DREG:
42 payload->dreg = *((uint32_t *)data);
44 case NFTNL_EXPR_PAYLOAD_BASE:
45 payload->base = *((uint32_t *)data);
47 case NFTNL_EXPR_PAYLOAD_OFFSET:
48 payload->offset = *((
unsigned int *)data);
50 case NFTNL_EXPR_PAYLOAD_LEN:
51 payload->len = *((
unsigned int *)data);
60 nftnl_expr_payload_get(
const struct nftnl_expr *e, uint16_t type,
66 case NFTNL_EXPR_PAYLOAD_DREG:
67 *data_len =
sizeof(payload->dreg);
68 return &payload->dreg;
69 case NFTNL_EXPR_PAYLOAD_BASE:
70 *data_len =
sizeof(payload->base);
71 return &payload->base;
72 case NFTNL_EXPR_PAYLOAD_OFFSET:
73 *data_len =
sizeof(payload->offset);
74 return &payload->offset;
75 case NFTNL_EXPR_PAYLOAD_LEN:
76 *data_len =
sizeof(payload->len);
82 static int nftnl_expr_payload_cb(
const struct nlattr *attr,
void *data)
84 const struct nlattr **tb = data;
85 int type = mnl_attr_get_type(attr);
87 if (mnl_attr_type_valid(attr, NFTA_PAYLOAD_MAX) < 0)
91 case NFTA_PAYLOAD_DREG:
92 case NFTA_PAYLOAD_BASE:
93 case NFTA_PAYLOAD_OFFSET:
94 case NFTA_PAYLOAD_LEN:
95 if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
105 nftnl_expr_payload_build(
struct nlmsghdr *nlh,
struct nftnl_expr *e)
109 if (e->flags & (1 << NFTNL_EXPR_PAYLOAD_DREG))
110 mnl_attr_put_u32(nlh, NFTA_PAYLOAD_DREG, htonl(payload->dreg));
111 if (e->flags & (1 << NFTNL_EXPR_PAYLOAD_BASE))
112 mnl_attr_put_u32(nlh, NFTA_PAYLOAD_BASE, htonl(payload->base));
113 if (e->flags & (1 << NFTNL_EXPR_PAYLOAD_OFFSET))
114 mnl_attr_put_u32(nlh, NFTA_PAYLOAD_OFFSET, htonl(payload->offset));
115 if (e->flags & (1 << NFTNL_EXPR_PAYLOAD_LEN))
116 mnl_attr_put_u32(nlh, NFTA_PAYLOAD_LEN, htonl(payload->len));
120 nftnl_expr_payload_parse(
struct nftnl_expr *e,
struct nlattr *attr)
123 struct nlattr *tb[NFTA_PAYLOAD_MAX+1] = {};
125 if (mnl_attr_parse_nested(attr, nftnl_expr_payload_cb, tb) < 0)
128 if (tb[NFTA_PAYLOAD_DREG]) {
129 payload->dreg = ntohl(mnl_attr_get_u32(tb[NFTA_PAYLOAD_DREG]));
130 e->flags |= (1 << NFTNL_EXPR_PAYLOAD_DREG);
132 if (tb[NFTA_PAYLOAD_BASE]) {
133 payload->base = ntohl(mnl_attr_get_u32(tb[NFTA_PAYLOAD_BASE]));
134 e->flags |= (1 << NFTNL_EXPR_PAYLOAD_BASE);
136 if (tb[NFTA_PAYLOAD_OFFSET]) {
137 payload->offset = ntohl(mnl_attr_get_u32(tb[NFTA_PAYLOAD_OFFSET]));
138 e->flags |= (1 << NFTNL_EXPR_PAYLOAD_OFFSET);
140 if (tb[NFTA_PAYLOAD_LEN]) {
141 payload->len = ntohl(mnl_attr_get_u32(tb[NFTA_PAYLOAD_LEN]));
142 e->flags |= (1 << NFTNL_EXPR_PAYLOAD_LEN);
148 static char *base2str_array[NFT_PAYLOAD_TRANSPORT_HEADER+1] = {
149 [NFT_PAYLOAD_LL_HEADER] =
"link",
150 [NFT_PAYLOAD_NETWORK_HEADER] =
"network",
151 [NFT_PAYLOAD_TRANSPORT_HEADER] =
"transport",
154 static const char *base2str(
enum nft_payload_bases base)
156 if (base > NFT_PAYLOAD_TRANSPORT_HEADER)
159 return base2str_array[base];
162 static inline int nftnl_str2base(
const char *base)
164 if (strcmp(base,
"link") == 0)
165 return NFT_PAYLOAD_LL_HEADER;
166 else if (strcmp(base,
"network") == 0)
167 return NFT_PAYLOAD_NETWORK_HEADER;
168 else if (strcmp(base,
"transport") == 0)
169 return NFT_PAYLOAD_TRANSPORT_HEADER;
177 nftnl_expr_payload_json_parse(
struct nftnl_expr *e, json_t *root,
178 struct nftnl_parse_err *err)
181 const char *base_str;
182 uint32_t reg, uval32;
185 if (nftnl_jansson_parse_reg(root,
"dreg", NFTNL_TYPE_U32, ®, err) == 0)
186 nftnl_expr_set_u32(e, NFTNL_EXPR_PAYLOAD_DREG, reg);
188 base_str = nftnl_jansson_parse_str(root,
"base", err);
189 if (base_str != NULL) {
190 base = nftnl_str2base(base_str);
194 nftnl_expr_set_u32(e, NFTNL_EXPR_PAYLOAD_BASE, base);
197 if (nftnl_jansson_parse_val(root,
"offset", NFTNL_TYPE_U32, &uval32,
199 nftnl_expr_set_u32(e, NFTNL_EXPR_PAYLOAD_OFFSET, uval32);
201 if (nftnl_jansson_parse_val(root,
"len", NFTNL_TYPE_U32, &uval32, err) == 0)
202 nftnl_expr_set_u32(e, NFTNL_EXPR_PAYLOAD_LEN, uval32);
212 nftnl_expr_payload_xml_parse(
struct nftnl_expr *e, mxml_node_t *tree,
213 struct nftnl_parse_err *err)
216 const char *base_str;
218 uint32_t dreg, offset, len;
220 if (nftnl_mxml_reg_parse(tree,
"dreg", &dreg, MXML_DESCEND_FIRST,
221 NFTNL_XML_MAND, err) == 0)
222 nftnl_expr_set_u32(e, NFTNL_EXPR_PAYLOAD_DREG, dreg);
224 base_str = nftnl_mxml_str_parse(tree,
"base", MXML_DESCEND_FIRST,
225 NFTNL_XML_MAND, err);
226 if (base_str != NULL) {
227 base = nftnl_str2base(base_str);
231 nftnl_expr_set_u32(e, NFTNL_EXPR_PAYLOAD_BASE, base);
234 if (nftnl_mxml_num_parse(tree,
"offset", MXML_DESCEND_FIRST, BASE_DEC,
235 &offset, NFTNL_TYPE_U32, NFTNL_XML_MAND, err) == 0)
236 nftnl_expr_set_u32(e, NFTNL_EXPR_PAYLOAD_OFFSET, offset);
239 if (nftnl_mxml_num_parse(tree,
"len", MXML_DESCEND_FIRST, BASE_DEC,
240 &len, NFTNL_TYPE_U32, NFTNL_XML_MAND, err) == 0)
241 nftnl_expr_set_u32(e, NFTNL_EXPR_PAYLOAD_LEN, len);
250 static int nftnl_expr_payload_export(
char *buf,
size_t size, uint32_t flags,
251 struct nftnl_expr *e,
int type)
254 NFTNL_BUF_INIT(b, buf, size);
256 if (e->flags & (1 << NFTNL_EXPR_PAYLOAD_DREG))
257 nftnl_buf_u32(&b, type, payload->dreg, DREG);
258 if (e->flags & (1 << NFTNL_EXPR_PAYLOAD_OFFSET))
259 nftnl_buf_u32(&b, type, payload->offset, OFFSET);
260 if (e->flags & (1 << NFTNL_EXPR_PAYLOAD_LEN))
261 nftnl_buf_u32(&b, type, payload->len, LEN);
262 if (e->flags & (1 << NFTNL_EXPR_PAYLOAD_BASE))
263 nftnl_buf_str(&b, type, base2str(payload->base), BASE);
265 return nftnl_buf_done(&b);
269 nftnl_expr_payload_snprintf(
char *buf,
size_t len, uint32_t type,
270 uint32_t flags,
struct nftnl_expr *e)
275 case NFTNL_OUTPUT_DEFAULT:
276 return snprintf(buf, len,
"load %ub @ %s header + %u => reg %u ",
277 payload->len, base2str(payload->base),
278 payload->offset, payload->dreg);
279 case NFTNL_OUTPUT_XML:
280 case NFTNL_OUTPUT_JSON:
281 return nftnl_expr_payload_export(buf, len, flags, e, type);
288 struct expr_ops expr_ops_payload = {
291 .max_attr = NFTA_PAYLOAD_MAX,
292 .set = nftnl_expr_payload_set,
293 .get = nftnl_expr_payload_get,
294 .parse = nftnl_expr_payload_parse,
295 .build = nftnl_expr_payload_build,
296 .snprintf = nftnl_expr_payload_snprintf,
297 .xml_parse = nftnl_expr_payload_xml_parse,
298 .json_parse = nftnl_expr_payload_json_parse,