From 48a71a20420e307d0a1d8a89ac9fc7b46ec5a1ca Mon Sep 17 00:00:00 2001 From: Laura Garcia Liebana Date: Sat, 13 Aug 2016 01:02:03 +0200 Subject: expr: add hash expression Support for the nft hash expression in libnftnl. Signed-off-by: Laura Garcia Liebana Signed-off-by: Pablo Neira Ayuso --- include/buffer.h | 2 + include/libnftnl/expr.h | 8 + include/linux/netfilter/nf_tables.h | 21 +++ src/Makefile.am | 1 + src/expr/hash.c | 294 ++++++++++++++++++++++++++++++++++++ src/expr_ops.c | 2 + tests/Makefile.am | 6 +- tests/nft-expr_hash-test.c | 102 +++++++++++++ tests/test-script.sh | 1 + 9 files changed, 436 insertions(+), 1 deletion(-) create mode 100644 src/expr/hash.c create mode 100644 tests/nft-expr_hash-test.c diff --git a/include/buffer.h b/include/buffer.h index cc4bfbc..a753c78 100644 --- a/include/buffer.h +++ b/include/buffer.h @@ -89,5 +89,7 @@ int nftnl_buf_reg(struct nftnl_buf *b, int type, union nftnl_data_reg *reg, #define DELETE "delete" #define REPLACE "replace" #define FLUSH "flush" +#define MODULUS "modulus" +#define SEED "seed" #endif diff --git a/include/libnftnl/expr.h b/include/libnftnl/expr.h index 17f60bd..1efe31c 100644 --- a/include/libnftnl/expr.h +++ b/include/libnftnl/expr.h @@ -191,6 +191,14 @@ enum { NFTNL_EXPR_FWD_SREG_DEV = NFTNL_EXPR_BASE, }; +enum { + NFTNL_EXPR_HASH_SREG = NFTNL_EXPR_BASE, + NFTNL_EXPR_HASH_DREG, + NFTNL_EXPR_HASH_LEN, + NFTNL_EXPR_HASH_MODULUS, + NFTNL_EXPR_HASH_SEED, +}; + /* * Compat */ diff --git a/include/linux/netfilter/nf_tables.h b/include/linux/netfilter/nf_tables.h index 01751fa..fcf9a39 100644 --- a/include/linux/netfilter/nf_tables.h +++ b/include/linux/netfilter/nf_tables.h @@ -1082,4 +1082,25 @@ enum nft_trace_types { __NFT_TRACETYPE_MAX }; #define NFT_TRACETYPE_MAX (__NFT_TRACETYPE_MAX - 1) + +/** + * enum nft_hash_attributes - nf_tables hash expression attributes + * + * @NFTA_HASH_SREG: source register (NLA_U32) + * @NFTA_HASH_DREG: destination register (NLA_U32) + * @NFTA_HASH_LEN: data length (NLA_U32) + * @NFTA_HASH_MODULUS: Modulus value (NLA_U32) + * @NFTA_HASH_SEED: hash initial value (NLA_U32) + */ +enum nft_hash_attributes { + NFTA_HASH_UNSPEC, + NFTA_HASH_SREG, + NFTA_HASH_DREG, + NFTA_HASH_LEN, + NFTA_HASH_MODULUS, + NFTA_HASH_SEED, + __NFTA_HASH_MAX +}; +#define NFTA_HASH_MAX (__NFTA_HASH_MAX - 1) + #endif /* _LINUX_NF_TABLES_H */ diff --git a/src/Makefile.am b/src/Makefile.am index 7e580e4..7725c79 100644 --- a/src/Makefile.am +++ b/src/Makefile.am @@ -45,4 +45,5 @@ libnftnl_la_SOURCES = utils.c \ expr/target.c \ expr/masq.c \ expr/redir.c \ + expr/hash.c \ libnftnl.map diff --git a/src/expr/hash.c b/src/expr/hash.c new file mode 100644 index 0000000..7309907 --- /dev/null +++ b/src/expr/hash.c @@ -0,0 +1,294 @@ +/* + * (C) 2016 by Laura Garcia + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published + * by the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + */ + +#include +#include +#include +#include +#include +#include + +#include "internal.h" +#include +#include +#include + +struct nftnl_expr_hash { + enum nft_registers sreg; + enum nft_registers dreg; + unsigned int len; + unsigned int modulus; + unsigned int seed; +}; + +static int +nftnl_expr_hash_set(struct nftnl_expr *e, uint16_t type, + const void *data, uint32_t data_len) +{ + struct nftnl_expr_hash *hash = nftnl_expr_data(e); + + switch (type) { + case NFTNL_EXPR_HASH_SREG: + hash->sreg = *((uint32_t *)data); + break; + case NFTNL_EXPR_HASH_DREG: + hash->dreg = *((uint32_t *)data); + break; + case NFTNL_EXPR_HASH_LEN: + hash->len = *((uint32_t *)data); + break; + case NFTNL_EXPR_HASH_MODULUS: + hash->modulus = *((uint32_t *)data); + break; + case NFTNL_EXPR_HASH_SEED: + hash->seed = *((uint32_t *)data); + break; + default: + return -1; + } + return 0; +} + +static const void * +nftnl_expr_hash_get(const struct nftnl_expr *e, uint16_t type, + uint32_t *data_len) +{ + struct nftnl_expr_hash *hash = nftnl_expr_data(e); + + switch (type) { + case NFTNL_EXPR_HASH_SREG: + *data_len = sizeof(hash->sreg); + return &hash->sreg; + case NFTNL_EXPR_HASH_DREG: + *data_len = sizeof(hash->dreg); + return &hash->dreg; + case NFTNL_EXPR_HASH_LEN: + *data_len = sizeof(hash->len); + return &hash->len; + case NFTNL_EXPR_HASH_MODULUS: + *data_len = sizeof(hash->modulus); + return &hash->modulus; + case NFTNL_EXPR_HASH_SEED: + *data_len = sizeof(hash->seed); + return &hash->seed; + } + return NULL; +} + +static int nftnl_expr_hash_cb(const struct nlattr *attr, void *data) +{ + const struct nlattr **tb = data; + int type = mnl_attr_get_type(attr); + + if (mnl_attr_type_valid(attr, NFTA_HASH_MAX) < 0) + return MNL_CB_OK; + + switch (type) { + case NFTA_HASH_SREG: + case NFTA_HASH_DREG: + case NFTA_HASH_LEN: + case NFTA_HASH_MODULUS: + case NFTA_HASH_SEED: + if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0) + abi_breakage(); + break; + } + + tb[type] = attr; + return MNL_CB_OK; +} + +static void +nftnl_expr_hash_build(struct nlmsghdr *nlh, const struct nftnl_expr *e) +{ + struct nftnl_expr_hash *hash = nftnl_expr_data(e); + + if (e->flags & (1 << NFTNL_EXPR_HASH_SREG)) + mnl_attr_put_u32(nlh, NFTA_HASH_SREG, htonl(hash->sreg)); + if (e->flags & (1 << NFTNL_EXPR_HASH_DREG)) + mnl_attr_put_u32(nlh, NFTA_HASH_DREG, htonl(hash->dreg)); + if (e->flags & (1 << NFTNL_EXPR_HASH_LEN)) + mnl_attr_put_u32(nlh, NFTA_HASH_LEN, htonl(hash->len)); + if (e->flags & (1 << NFTNL_EXPR_HASH_MODULUS)) + mnl_attr_put_u32(nlh, NFTA_HASH_MODULUS, htonl(hash->modulus)); + if (e->flags & (1 << NFTNL_EXPR_HASH_SEED)) + mnl_attr_put_u32(nlh, NFTA_HASH_SEED, htonl(hash->seed)); + +} + +static int +nftnl_expr_hash_parse(struct nftnl_expr *e, struct nlattr *attr) +{ + struct nftnl_expr_hash *hash = nftnl_expr_data(e); + struct nlattr *tb[NFTA_HASH_MAX+1] = {}; + int ret = 0; + + if (mnl_attr_parse_nested(attr, nftnl_expr_hash_cb, tb) < 0) + return -1; + + if (tb[NFTA_HASH_SREG]) { + hash->sreg = ntohl(mnl_attr_get_u32(tb[NFTA_HASH_SREG])); + e->flags |= (1 << NFTNL_EXPR_HASH_SREG); + } + if (tb[NFTA_HASH_DREG]) { + hash->dreg = ntohl(mnl_attr_get_u32(tb[NFTA_HASH_DREG])); + e->flags |= (1 << NFTNL_EXPR_HASH_DREG); + } + if (tb[NFTA_HASH_LEN]) { + hash->len = ntohl(mnl_attr_get_u32(tb[NFTA_HASH_LEN])); + e->flags |= (1 << NFTNL_EXPR_HASH_LEN); + } + if (tb[NFTA_HASH_MODULUS]) { + hash->modulus = ntohl(mnl_attr_get_u32(tb[NFTA_HASH_MODULUS])); + e->flags |= (1 << NFTNL_EXPR_HASH_MODULUS); + } + if (tb[NFTA_HASH_SEED]) { + hash->seed = ntohl(mnl_attr_get_u32(tb[NFTA_HASH_SEED])); + e->flags |= (1 << NFTNL_EXPR_HASH_SEED); + } + + return ret; +} + +static int nftnl_expr_hash_json_parse(struct nftnl_expr *e, json_t *root, + struct nftnl_parse_err *err) +{ +#ifdef JSON_PARSING + uint32_t sreg, dreg, len, modulus, seed; + + if (nftnl_jansson_parse_reg(root, "sreg", NFTNL_TYPE_U32, + &sreg, err) == 0) + nftnl_expr_set_u32(e, NFTNL_EXPR_HASH_SREG, sreg); + + if (nftnl_jansson_parse_reg(root, "dreg", NFTNL_TYPE_U32, + &dreg, err) == 0) + nftnl_expr_set_u32(e, NFTNL_EXPR_HASH_DREG, dreg); + + if (nftnl_jansson_parse_val(root, "len", NFTNL_TYPE_U32, + &len, err) == 0) + nftnl_expr_set_u32(e, NFTNL_EXPR_HASH_LEN, len); + + if (nftnl_jansson_parse_val(root, "modulus", NFTNL_TYPE_U32, + &modulus, err) == 0) + nftnl_expr_set_u32(e, NFTNL_EXPR_HASH_MODULUS, modulus); + + if (nftnl_jansson_parse_val(root, "seed", NFTNL_TYPE_U32, + &seed, err) == 0) + nftnl_expr_set_u32(e, NFTNL_EXPR_HASH_SEED, seed); + + return 0; +#else + errno = EOPNOTSUPP; + return -1; +#endif +} + + +static int nftnl_expr_hash_xml_parse(struct nftnl_expr *e, + mxml_node_t *tree, + struct nftnl_parse_err *err) +{ +#ifdef XML_PARSING + uint32_t sreg, dreg, len, modulus, seed; + + if (nftnl_mxml_reg_parse(tree, "sreg", &sreg, MXML_DESCEND_FIRST, + NFTNL_XML_MAND, err) == 0) + nftnl_expr_set_u32(e, NFTNL_EXPR_HASH_SREG, sreg); + + if (nftnl_mxml_reg_parse(tree, "dreg", &dreg, MXML_DESCEND_FIRST, + NFTNL_XML_MAND, err) == 0) + nftnl_expr_set_u32(e, NFTNL_EXPR_HASH_DREG, dreg); + + if (nftnl_mxml_num_parse(tree, "len", MXML_DESCEND_FIRST, BASE_DEC, + &len, NFTNL_TYPE_U32, NFTNL_XML_MAND, + err) == 0) + nftnl_expr_set_u32(e, NFTNL_EXPR_HASH_LEN, len); + + if (nftnl_mxml_num_parse(tree, "modulus", MXML_DESCEND_FIRST, BASE_DEC, + &modulus, NFTNL_TYPE_U32, NFTNL_XML_MAND, + err) == 0) + nftnl_expr_set_u32(e, NFTNL_EXPR_HASH_MODULUS, modulus); + + if (nftnl_mxml_num_parse(tree, "seed", MXML_DESCEND_FIRST, BASE_DEC, + &seed, NFTNL_TYPE_U32, NFTNL_XML_MAND, + err) == 0) + nftnl_expr_set_u32(e, NFTNL_EXPR_HASH_SEED, seed); + + return 0; +#else + errno = EOPNOTSUPP; + return -1; +#endif +} + +static int +nftnl_expr_hash_snprintf_default(char *buf, size_t size, + const struct nftnl_expr *e) +{ + struct nftnl_expr_hash *hash = nftnl_expr_data(e); + int len = size, offset = 0, ret; + + ret = snprintf(buf, len, "reg %u = jhash(reg %u, %u, %u) %% modulus %u", + hash->dreg, hash->sreg, hash->len, hash->seed, + hash->modulus); + SNPRINTF_BUFFER_SIZE(ret, size, len, offset); + + return offset; +} + +static int nftnl_expr_hash_export(char *buf, size_t size, + const struct nftnl_expr *e, int type) +{ + struct nftnl_expr_hash *hash = nftnl_expr_data(e); + + NFTNL_BUF_INIT(b, buf, size); + + if (e->flags & (1 << NFTNL_EXPR_HASH_SREG)) + nftnl_buf_u32(&b, type, hash->sreg, SREG); + if (e->flags & (1 << NFTNL_EXPR_HASH_DREG)) + nftnl_buf_u32(&b, type, hash->dreg, DREG); + if (e->flags & (1 << NFTNL_EXPR_HASH_LEN)) + nftnl_buf_u32(&b, type, hash->len, LEN); + if (e->flags & (1 << NFTNL_EXPR_HASH_MODULUS)) + nftnl_buf_u32(&b, type, hash->modulus, MODULUS); + if (e->flags & (1 << NFTNL_EXPR_HASH_SEED)) + nftnl_buf_u32(&b, type, hash->seed, SEED); + + return nftnl_buf_done(&b); +} + +static int +nftnl_expr_hash_snprintf(char *buf, size_t len, uint32_t type, + uint32_t flags, const struct nftnl_expr *e) +{ + switch (type) { + case NFTNL_OUTPUT_DEFAULT: + return nftnl_expr_hash_snprintf_default(buf, len, e); + case NFTNL_OUTPUT_XML: + case NFTNL_OUTPUT_JSON: + return nftnl_expr_hash_export(buf, len, e, type); + default: + break; + } + return -1; +} + +struct expr_ops expr_ops_hash = { + .name = "hash", + .alloc_len = sizeof(struct nftnl_expr_hash), + .max_attr = NFTA_HASH_MAX, + .set = nftnl_expr_hash_set, + .get = nftnl_expr_hash_get, + .parse = nftnl_expr_hash_parse, + .build = nftnl_expr_hash_build, + .snprintf = nftnl_expr_hash_snprintf, + .xml_parse = nftnl_expr_hash_xml_parse, + .json_parse = nftnl_expr_hash_json_parse, +}; diff --git a/src/expr_ops.c b/src/expr_ops.c index ae515af..9b10029 100644 --- a/src/expr_ops.c +++ b/src/expr_ops.c @@ -26,6 +26,7 @@ extern struct expr_ops expr_ops_reject; extern struct expr_ops expr_ops_queue; extern struct expr_ops expr_ops_target; extern struct expr_ops expr_ops_dynset; +extern struct expr_ops expr_ops_hash; static struct expr_ops *expr_ops[] = { &expr_ops_bitwise, @@ -50,6 +51,7 @@ static struct expr_ops *expr_ops[] = { &expr_ops_queue, &expr_ops_target, &expr_ops_dynset, + &expr_ops_hash, NULL, }; diff --git a/tests/Makefile.am b/tests/Makefile.am index 0377081..86766f3 100644 --- a/tests/Makefile.am +++ b/tests/Makefile.am @@ -29,7 +29,8 @@ check_PROGRAMS = nft-parsing-test \ nft-expr_queue-test \ nft-expr_redir-test \ nft-expr_reject-test \ - nft-expr_target-test + nft-expr_target-test \ + nft-expr_hash-test nft_parsing_test_SOURCES = nft-parsing-test.c nft_parsing_test_LDADD = ../src/libnftnl.la ${LIBMNL_LIBS} ${LIBXML_LIBS} ${LIBJSON_LIBS} @@ -108,3 +109,6 @@ nft_expr_redir_test_LDADD = ../src/libnftnl.la ${LIBMNL_LIBS} nft_expr_target_test_SOURCES = nft-expr_target-test.c nft_expr_target_test_LDADD = ../src/libnftnl.la ${LIBMNL_LIBS} + +nft_expr_hash_test_SOURCES = nft-expr_hash-test.c +nft_expr_hash_test_LDADD = ../src/libnftnl.la ${LIBMNL_LIBS} diff --git a/tests/nft-expr_hash-test.c b/tests/nft-expr_hash-test.c new file mode 100644 index 0000000..699197c --- /dev/null +++ b/tests/nft-expr_hash-test.c @@ -0,0 +1,102 @@ +/* + * (C) 2016 by Laura Garcia + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + */ + +#include +#include +#include +#include +#include + +#include +#include +#include +#include + +static int test_ok = 1; + +static void print_err(const char *msg) +{ + test_ok = 0; + printf("\033[31mERROR:\e[0m %s\n", msg); +} + +static void cmp_nftnl_expr(struct nftnl_expr *rule_a, + struct nftnl_expr *rule_b) +{ + if (nftnl_expr_get_u32(rule_a, NFTNL_EXPR_HASH_SREG) != + nftnl_expr_get_u32(rule_b, NFTNL_EXPR_HASH_SREG)) + print_err("Expr NFTNL_EXPR_HASH_SREG mismatches"); + if (nftnl_expr_get_u32(rule_a, NFTNL_EXPR_HASH_DREG) != + nftnl_expr_get_u32(rule_b, NFTNL_EXPR_HASH_DREG)) + print_err("Expr NFTNL_EXPR_HASH_DREG mismatches"); + if (nftnl_expr_get_u32(rule_a, NFTNL_EXPR_HASH_MODULUS) != + nftnl_expr_get_u32(rule_b, NFTNL_EXPR_HASH_MODULUS)) + print_err("Expr NFTNL_EXPR_HASH_MODULUS mismatches"); + if (nftnl_expr_get_u32(rule_a, NFTNL_EXPR_HASH_SEED) != + nftnl_expr_get_u32(rule_b, NFTNL_EXPR_HASH_SEED)) + print_err("Expr NFTNL_EXPR_HASH_SEED mismatches"); +} + +int main(int argc, char *argv[]) +{ + struct nftnl_rule *a, *b; + struct nftnl_expr *ex; + struct nlmsghdr *nlh; + char buf[4096]; + struct nftnl_expr_iter *iter_a, *iter_b; + struct nftnl_expr *rule_a, *rule_b; + + a = nftnl_rule_alloc(); + b = nftnl_rule_alloc(); + if (a == NULL || b == NULL) + print_err("OOM"); + ex = nftnl_expr_alloc("hash"); + if (ex == NULL) + print_err("OOM"); + + nftnl_expr_set_u32(ex, NFTNL_EXPR_HASH_SREG, 0x1234568); + nftnl_expr_set_u32(ex, NFTNL_EXPR_HASH_DREG, 0x78123456); + nftnl_expr_set_u32(ex, NFTNL_EXPR_HASH_MODULUS, 0x78123456); + nftnl_expr_set_u32(ex, NFTNL_EXPR_HASH_SEED, 0x78123456); + + nftnl_rule_add_expr(a, ex); + + nlh = nftnl_rule_nlmsg_build_hdr(buf, NFT_MSG_NEWRULE, AF_INET, 0, 1234); + nftnl_rule_nlmsg_build_payload(nlh, a); + if (nftnl_rule_nlmsg_parse(nlh, b) < 0) + print_err("parsing problems"); + + iter_a = nftnl_expr_iter_create(a); + iter_b = nftnl_expr_iter_create(b); + if (iter_a == NULL || iter_b == NULL) + print_err("OOM"); + + rule_a = nftnl_expr_iter_next(iter_a); + rule_b = nftnl_expr_iter_next(iter_b); + if (rule_a == NULL || rule_b == NULL) + print_err("OOM"); + + cmp_nftnl_expr(rule_a, rule_b); + + if (nftnl_expr_iter_next(iter_a) != NULL || + nftnl_expr_iter_next(iter_b) != NULL) + print_err("More 1 expr."); + + nftnl_expr_iter_destroy(iter_a); + nftnl_expr_iter_destroy(iter_b); + nftnl_rule_free(a); + nftnl_rule_free(b); + + if (!test_ok) + exit(EXIT_FAILURE); + + printf("%s: \033[32mOK\e[0m\n", argv[0]); + return EXIT_SUCCESS; +} diff --git a/tests/test-script.sh b/tests/test-script.sh index ba13571..48f002f 100755 --- a/tests/test-script.sh +++ b/tests/test-script.sh @@ -20,6 +20,7 @@ ./nft-expr_payload-test ./nft-expr_reject-test ./nft-expr_target-test +./nft-expr_hash-test ./nft-rule-test ./nft-set-test ./nft-table-test -- cgit v1.2.3