From 39646feffc0fc247ba8098adb33f76f0a12a9b7a Mon Sep 17 00:00:00 2001 From: Laura Garcia Liebana Date: Sun, 14 Aug 2016 16:48:48 +0200 Subject: expr: add number generation expression Support for the nft ng expression within libnftnl. Signed-off-by: Laura Garcia Liebana Signed-off-by: Pablo Neira Ayuso --- include/buffer.h | 1 + include/libnftnl/expr.h | 6 + include/linux/netfilter/nf_tables.h | 27 ++++ src/Makefile.am | 1 + src/expr/numgen.c | 251 ++++++++++++++++++++++++++++++++++++ src/expr_ops.c | 2 + tests/Makefile.am | 4 + tests/nft-expr_numgen-test.c | 98 ++++++++++++++ tests/test-script.sh | 1 + 9 files changed, 391 insertions(+) create mode 100644 src/expr/numgen.c create mode 100644 tests/nft-expr_numgen-test.c diff --git a/include/buffer.h b/include/buffer.h index a753c78..8cfe377 100644 --- a/include/buffer.h +++ b/include/buffer.h @@ -82,6 +82,7 @@ int nftnl_buf_reg(struct nftnl_buf *b, int type, union nftnl_data_reg *reg, #define TOTAL "total" #define TYPE "type" #define UNIT "unit" +#define UNTIL "until" #define USE "use" #define XOR "xor" #define ADD "add" diff --git a/include/libnftnl/expr.h b/include/libnftnl/expr.h index 663cbf3..8815154 100644 --- a/include/libnftnl/expr.h +++ b/include/libnftnl/expr.h @@ -50,6 +50,12 @@ enum { NFTNL_EXPR_PAYLOAD_CSUM_OFFSET, }; +enum { + NFTNL_EXPR_NG_DREG = NFTNL_EXPR_BASE, + NFTNL_EXPR_NG_UNTIL, + NFTNL_EXPR_NG_TYPE, +}; + enum { NFTNL_EXPR_META_KEY = NFTNL_EXPR_BASE, NFTNL_EXPR_META_DREG, diff --git a/include/linux/netfilter/nf_tables.h b/include/linux/netfilter/nf_tables.h index 6390d6e..0b11abf 100644 --- a/include/linux/netfilter/nf_tables.h +++ b/include/linux/netfilter/nf_tables.h @@ -666,6 +666,33 @@ enum nft_exthdr_attributes { }; #define NFTA_EXTHDR_MAX (__NFTA_EXTHDR_MAX - 1) +/** + * enum nft_ng_attributes - nf_tables number generator expression attributes + * + * @NFTA_NG_DREG: destination register (NLA_U32) + * @NFTA_NG_UNTIL: limit value (NLA_U32) + * @NFTA_NG_TYPE: type of operation (NLA_U32) + */ +enum nft_ng_attributes { + NFTA_NG_UNSPEC, + NFTA_NG_DREG, + NFTA_NG_UNTIL, + NFTA_NG_TYPE, + __NFTA_NG_MAX +}; +#define NFTA_NG_MAX (__NFTA_NG_MAX - 1) + +/** + * enum nft_ng_type - nf_tables number generator expression reject types + * + * @NFT_NG_INCREMENTAL: Incremental number generator + * @NFT_NG_RANDOM: Random number generator + */ +enum nft_ng_type { + NFT_NG_INCREMENTAL, + NFT_NG_RANDOM +}; + /** * enum nft_meta_keys - nf_tables meta expression keys * diff --git a/src/Makefile.am b/src/Makefile.am index 3d710c5..4a91cdb 100644 --- a/src/Makefile.am +++ b/src/Makefile.am @@ -38,6 +38,7 @@ libnftnl_la_SOURCES = utils.c \ expr/immediate.c \ expr/match.c \ expr/meta.c \ + expr/numgen.c \ expr/nat.c \ expr/payload.c \ expr/queue.c \ diff --git a/src/expr/numgen.c b/src/expr/numgen.c new file mode 100644 index 0000000..0981d72 --- /dev/null +++ b/src/expr/numgen.c @@ -0,0 +1,251 @@ +/* + * (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_ng { + enum nft_registers dreg; + unsigned int until; + enum nft_ng_type type; +}; + +static int +nftnl_expr_ng_set(struct nftnl_expr *e, uint16_t type, + const void *data, uint32_t data_len) +{ + struct nftnl_expr_ng *ng = nftnl_expr_data(e); + + switch (type) { + case NFTNL_EXPR_NG_DREG: + ng->dreg = *((uint32_t *)data); + break; + case NFTNL_EXPR_NG_UNTIL: + ng->until = *((uint32_t *)data); + break; + case NFTNL_EXPR_NG_TYPE: + ng->type = *((uint32_t *)data); + break; + default: + return -1; + } + return 0; +} + +static const void * +nftnl_expr_ng_get(const struct nftnl_expr *e, uint16_t type, + uint32_t *data_len) +{ + struct nftnl_expr_ng *ng = nftnl_expr_data(e); + + switch (type) { + case NFTNL_EXPR_NG_DREG: + *data_len = sizeof(ng->dreg); + return &ng->dreg; + case NFTNL_EXPR_NG_UNTIL: + *data_len = sizeof(ng->until); + return &ng->until; + case NFTNL_EXPR_NG_TYPE: + *data_len = sizeof(ng->type); + return &ng->type; + } + return NULL; +} + +static int nftnl_expr_ng_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_NG_MAX) < 0) + return MNL_CB_OK; + + switch (type) { + case NFTA_NG_DREG: + case NFTA_NG_UNTIL: + case NFTA_NG_TYPE: + if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0) + abi_breakage(); + break; + } + + tb[type] = attr; + return MNL_CB_OK; +} + +static void +nftnl_expr_ng_build(struct nlmsghdr *nlh, const struct nftnl_expr *e) +{ + struct nftnl_expr_ng *ng = nftnl_expr_data(e); + + if (e->flags & (1 << NFTNL_EXPR_NG_DREG)) + mnl_attr_put_u32(nlh, NFTA_NG_DREG, htonl(ng->dreg)); + if (e->flags & (1 << NFTNL_EXPR_NG_UNTIL)) + mnl_attr_put_u32(nlh, NFTA_NG_UNTIL, htonl(ng->until)); + if (e->flags & (1 << NFTNL_EXPR_NG_TYPE)) + mnl_attr_put_u32(nlh, NFTA_NG_TYPE, htonl(ng->type)); +} + +static int +nftnl_expr_ng_parse(struct nftnl_expr *e, struct nlattr *attr) +{ + struct nftnl_expr_ng *ng = nftnl_expr_data(e); + struct nlattr *tb[NFTA_NG_MAX+1] = {}; + int ret = 0; + + if (mnl_attr_parse_nested(attr, nftnl_expr_ng_cb, tb) < 0) + return -1; + + if (tb[NFTA_NG_DREG]) { + ng->dreg = ntohl(mnl_attr_get_u32(tb[NFTA_NG_DREG])); + e->flags |= (1 << NFTNL_EXPR_NG_DREG); + } + if (tb[NFTA_NG_UNTIL]) { + ng->until = ntohl(mnl_attr_get_u32(tb[NFTA_NG_UNTIL])); + e->flags |= (1 << NFTNL_EXPR_NG_UNTIL); + } + if (tb[NFTA_NG_TYPE]) { + ng->type = ntohl(mnl_attr_get_u32(tb[NFTA_NG_TYPE])); + e->flags |= (1 << NFTNL_EXPR_NG_TYPE); + } + + return ret; +} + +static int nftnl_expr_ng_json_parse(struct nftnl_expr *e, json_t *root, + struct nftnl_parse_err *err) +{ +#ifdef JSON_PARSING + uint32_t dreg, until, type; + + if (nftnl_jansson_parse_reg(root, "dreg", NFTNL_TYPE_U32, + &dreg, err) == 0) + nftnl_expr_set_u32(e, NFTNL_EXPR_NG_DREG, dreg); + + if (nftnl_jansson_parse_val(root, "until", NFTNL_TYPE_U32, + &until, err) == 0) + nftnl_expr_set_u32(e, NFTNL_EXPR_NG_UNTIL, until); + + if (nftnl_jansson_parse_val(root, "type", NFTNL_TYPE_U32, + &type, err) == 0) + nftnl_expr_set_u32(e, NFTNL_EXPR_NG_TYPE, type); + + return 0; +#else + errno = EOPNOTSUPP; + return -1; +#endif +} + + +static int nftnl_expr_ng_xml_parse(struct nftnl_expr *e, + mxml_node_t *tree, + struct nftnl_parse_err *err) +{ +#ifdef XML_PARSING + uint32_t dreg, until, type; + + if (nftnl_mxml_reg_parse(tree, "dreg", &dreg, MXML_DESCEND_FIRST, + NFTNL_XML_MAND, err) == 0) + nftnl_expr_set_u32(e, NFTNL_EXPR_NG_DREG, dreg); + + if (nftnl_mxml_num_parse(tree, "until", MXML_DESCEND_FIRST, BASE_DEC, + &until, NFTNL_TYPE_U32, NFTNL_XML_MAND, + err) == 0) + nftnl_expr_set_u32(e, NFTNL_EXPR_NG_UNTIL, until); + + if (nftnl_mxml_num_parse(tree, "type", MXML_DESCEND_FIRST, BASE_DEC, + &type, NFTNL_TYPE_U32, NFTNL_XML_MAND, + err) == 0) + nftnl_expr_set_u32(e, NFTNL_EXPR_NG_TYPE, type); + + return 0; +#else + errno = EOPNOTSUPP; + return -1; +#endif +} + +static int +nftnl_expr_ng_snprintf_default(char *buf, size_t size, + const struct nftnl_expr *e) +{ + struct nftnl_expr_ng *ng = nftnl_expr_data(e); + int len = size, offset = 0, ret; + + if (ng->type == NFT_NG_INCREMENTAL) { + ret = snprintf(buf, len, "reg %u = inc(%u)", ng->dreg, + ng->until); + SNPRINTF_BUFFER_SIZE(ret, size, len, offset); + } + + if (ng->type == NFT_NG_RANDOM) { + ret = snprintf(buf, len, "reg %u = random(%u)", ng->dreg, + ng->until); + SNPRINTF_BUFFER_SIZE(ret, size, len, offset); + } + + return offset; +} + +static int nftnl_expr_ng_export(char *buf, size_t size, + const struct nftnl_expr *e, int type) +{ + struct nftnl_expr_ng *ng = nftnl_expr_data(e); + + NFTNL_BUF_INIT(b, buf, size); + + if (e->flags & (1 << NFTNL_EXPR_NG_DREG)) + nftnl_buf_u32(&b, type, ng->dreg, DREG); + if (e->flags & (1 << NFTNL_EXPR_NG_UNTIL)) + nftnl_buf_u32(&b, type, ng->until, UNTIL); + if (e->flags & (1 << NFTNL_EXPR_NG_TYPE)) + nftnl_buf_u32(&b, type, ng->type, TYPE); + + return nftnl_buf_done(&b); +} + +static int +nftnl_expr_ng_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_ng_snprintf_default(buf, len, e); + case NFTNL_OUTPUT_XML: + case NFTNL_OUTPUT_JSON: + return nftnl_expr_ng_export(buf, len, e, type); + default: + break; + } + return -1; +} + +struct expr_ops expr_ops_ng = { + .name = "numgen", + .alloc_len = sizeof(struct nftnl_expr_ng), + .max_attr = NFTA_NG_MAX, + .set = nftnl_expr_ng_set, + .get = nftnl_expr_ng_get, + .parse = nftnl_expr_ng_parse, + .build = nftnl_expr_ng_build, + .snprintf = nftnl_expr_ng_snprintf, + .xml_parse = nftnl_expr_ng_xml_parse, + .json_parse = nftnl_expr_ng_json_parse, +}; diff --git a/src/expr_ops.c b/src/expr_ops.c index 876d7ad..2a047d2 100644 --- a/src/expr_ops.c +++ b/src/expr_ops.c @@ -19,6 +19,7 @@ extern struct expr_ops expr_ops_lookup; extern struct expr_ops expr_ops_masq; extern struct expr_ops expr_ops_match; extern struct expr_ops expr_ops_meta; +extern struct expr_ops expr_ops_ng; extern struct expr_ops expr_ops_nat; extern struct expr_ops expr_ops_payload; extern struct expr_ops expr_ops_redir; @@ -45,6 +46,7 @@ static struct expr_ops *expr_ops[] = { &expr_ops_masq, &expr_ops_match, &expr_ops_meta, + &expr_ops_ng, &expr_ops_nat, &expr_ops_payload, &expr_ops_redir, diff --git a/tests/Makefile.am b/tests/Makefile.am index 4b421eb..e5588c9 100644 --- a/tests/Makefile.am +++ b/tests/Makefile.am @@ -24,6 +24,7 @@ check_PROGRAMS = nft-parsing-test \ nft-expr_match-test \ nft-expr_masq-test \ nft-expr_meta-test \ + nft-expr_numgen-test \ nft-expr_nat-test \ nft-expr_payload-test \ nft-expr_queue-test \ @@ -93,6 +94,9 @@ nft_expr_masq_test_LDADD = ../src/libnftnl.la ${LIBMNL_LIBS} nft_expr_meta_test_SOURCES = nft-expr_meta-test.c nft_expr_meta_test_LDADD = ../src/libnftnl.la ${LIBMNL_LIBS} +nft_expr_numgen_test_SOURCES = nft-expr_numgen-test.c +nft_expr_numgen_test_LDADD = ../src/libnftnl.la ${LIBMNL_LIBS} + nft_expr_nat_test_SOURCES = nft-expr_nat-test.c nft_expr_nat_test_LDADD = ../src/libnftnl.la ${LIBMNL_LIBS} diff --git a/tests/nft-expr_numgen-test.c b/tests/nft-expr_numgen-test.c new file mode 100644 index 0000000..b78ee76 --- /dev/null +++ b/tests/nft-expr_numgen-test.c @@ -0,0 +1,98 @@ +/* + * (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_NG_DREG) != + nftnl_expr_get_u32(rule_b, NFTNL_EXPR_NG_DREG)) + print_err("Expr NFTNL_EXPR_NG_DREG mismatches"); + if (nftnl_expr_get_u32(rule_a, NFTNL_EXPR_NG_UNTIL) != + nftnl_expr_get_u32(rule_b, NFTNL_EXPR_NG_UNTIL)) + print_err("Expr NFTNL_EXPR_NG_UNTIL mismatches"); + if (nftnl_expr_get_u32(rule_a, NFTNL_EXPR_NG_TYPE) != + nftnl_expr_get_u32(rule_b, NFTNL_EXPR_NG_TYPE)) + print_err("Expr NFTNL_EXPR_NG_TYPE 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("numgen"); + if (ex == NULL) + print_err("OOM"); + + nftnl_expr_set_u32(ex, NFTNL_EXPR_NG_DREG, 0x1234568); + nftnl_expr_set_u32(ex, NFTNL_EXPR_NG_UNTIL, 0x78123456); + nftnl_expr_set_u32(ex, NFTNL_EXPR_NG_TYPE, NFT_NG_INCREMENTAL); + + 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 0c89e7c..dcd9080 100755 --- a/tests/test-script.sh +++ b/tests/test-script.sh @@ -14,6 +14,7 @@ ./nft-expr_match-test ./nft-expr_masq-test ./nft-expr_meta-test +./nft-expr_numgen-test ./nft-expr_queue-test ./nft-expr_redir-test ./nft-expr_nat-test -- cgit v1.2.3