From ad92bd5c07eb6e7d94a4e11031cceef769598891 Mon Sep 17 00:00:00 2001 From: Tomasz Bursztyka Date: Thu, 15 Nov 2012 04:40:25 +0000 Subject: expr: Add support for NAT expressions Signed-off-by: Tomasz Bursztyka --- include/libnftables/expr.h | 9 ++ include/linux/netfilter/nf_tables.h | 9 +- src/Makefile.am | 1 + src/expr/nat.c | 250 ++++++++++++++++++++++++++++++++++++ src/expr_ops.c | 2 + 5 files changed, 267 insertions(+), 4 deletions(-) create mode 100644 src/expr/nat.c diff --git a/include/libnftables/expr.h b/include/libnftables/expr.h index cddfbcf..a39cb48 100644 --- a/include/libnftables/expr.h +++ b/include/libnftables/expr.h @@ -81,6 +81,15 @@ enum { NFT_EXPR_MT_INFO, }; +enum { + NFT_EXPR_NAT_TYPE = NFT_RULE_EXPR_ATTR_BASE, + NFT_EXPR_NAT_FAMILY, + NFT_EXPR_NAT_REG_ADDR_MIN, + NFT_EXPR_NAT_REG_ADDR_MAX, + NFT_EXPR_NAT_REG_PROTO_MIN, + NFT_EXPR_NAT_REG_PROTO_MAX, +}; + #ifdef __cplusplus } /* extern "C" */ #endif diff --git a/include/linux/netfilter/nf_tables.h b/include/linux/netfilter/nf_tables.h index 28aa0ee..5d995d6 100644 --- a/include/linux/netfilter/nf_tables.h +++ b/include/linux/netfilter/nf_tables.h @@ -406,10 +406,11 @@ enum nft_nat_types { enum nft_nat_attributes { NFTA_NAT_UNSPEC, NFTA_NAT_TYPE, - NFTA_NAT_ADDR_MIN, - NFTA_NAT_ADDR_MAX, - NFTA_NAT_PROTO_MIN, - NFTA_NAT_PROTO_MAX, + NFTA_NAT_FAMILY, + NFTA_NAT_REG_ADDR_MIN, + NFTA_NAT_REG_ADDR_MAX, + NFTA_NAT_REG_PROTO_MIN, + NFTA_NAT_REG_PROTO_MAX, __NFTA_NAT_MAX }; #define NFTA_NAT_MAX (__NFTA_NAT_MAX - 1) diff --git a/src/Makefile.am b/src/Makefile.am index 4cca790..18d2c22 100644 --- a/src/Makefile.am +++ b/src/Makefile.am @@ -16,6 +16,7 @@ libnftables_la_SOURCES = table.c \ expr/immediate.c \ expr/match.c \ expr/meta.c \ + expr/nat.c \ expr/payload.c \ expr/target.c \ libnftables.map \ diff --git a/src/expr/nat.c b/src/expr/nat.c new file mode 100644 index 0000000..acd9839 --- /dev/null +++ b/src/expr/nat.c @@ -0,0 +1,250 @@ +/* + * (C) 2012 Intel Corporation + * + * 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. + * + * Authors: + * Tomasz Bursztyka + */ + +#include "internal.h" + +#include +#include +#include +#include +#include +#include +#include "expr_ops.h" + +struct nft_expr_nat { + enum nft_registers sreg_addr_min; + enum nft_registers sreg_addr_max; + enum nft_registers sreg_proto_min; + enum nft_registers sreg_proto_max; + int family; + enum nft_nat_types type; +}; + +static int +nft_rule_expr_nat_set(struct nft_rule_expr *e, uint16_t type, + const void *data, size_t data_len) +{ + struct nft_expr_nat *nat = (struct nft_expr_nat *)e->data; + + switch(type) { + case NFT_EXPR_NAT_TYPE: + nat->type = *((uint32_t *)data); + break; + case NFT_EXPR_NAT_FAMILY: + nat->family = *((uint32_t *)data); + break; + case NFT_EXPR_NAT_REG_ADDR_MIN: + nat->sreg_addr_min = *((uint32_t *)data); + break; + case NFT_EXPR_NAT_REG_ADDR_MAX: + nat->sreg_addr_max = *((uint32_t *)data); + break; + case NFT_EXPR_NAT_REG_PROTO_MIN: + nat->sreg_proto_min = *((uint32_t *)data); + break; + case NFT_EXPR_NAT_REG_PROTO_MAX: + nat->sreg_proto_max = *((uint32_t *)data); + break; + default: + return -1; + } + + return 0; +} + +static const void * +nft_rule_expr_nat_get(struct nft_rule_expr *e, uint16_t type, size_t *data_len) +{ + struct nft_expr_nat *nat = (struct nft_expr_nat *)e->data; + + switch(type) { + case NFT_EXPR_NAT_TYPE: + if (e->flags & (1 << NFT_EXPR_NAT_TYPE)) { + *data_len = sizeof(nat->type); + return &nat->type; + } + break; + case NFT_EXPR_NAT_FAMILY: + if (e->flags & (1 << NFT_EXPR_NAT_FAMILY)) { + *data_len = sizeof(nat->family); + return &nat->family; + } + break; + case NFT_EXPR_NAT_REG_ADDR_MIN: + if (e->flags & (1 << NFT_EXPR_NAT_REG_ADDR_MIN)) { + *data_len = sizeof(nat->sreg_addr_min); + return &nat->sreg_addr_min; + } + break; + case NFT_EXPR_NAT_REG_ADDR_MAX: + if (e->flags & (1 << NFT_EXPR_NAT_REG_ADDR_MAX)) { + *data_len = sizeof(nat->sreg_addr_max); + return &nat->sreg_addr_max; + } + break; + case NFT_EXPR_NAT_REG_PROTO_MIN: + if (e->flags & (1 << NFT_EXPR_NAT_REG_PROTO_MIN)) { + *data_len = sizeof(nat->sreg_proto_min); + return &nat->sreg_proto_min; + } + break; + case NFT_EXPR_NAT_REG_PROTO_MAX: + if (e->flags & (1 << NFT_EXPR_NAT_REG_PROTO_MAX)) { + *data_len = sizeof(nat->sreg_proto_max); + return &nat->sreg_proto_max; + } + break; + default: + break; + } + + return NULL; +} + +static int nft_rule_expr_nat_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_NAT_MAX) < 0) + return MNL_CB_OK; + + switch(type) { + case NFTA_NAT_TYPE: + case NFTA_NAT_FAMILY: + case NFTA_NAT_REG_ADDR_MIN: + case NFTA_NAT_REG_ADDR_MAX: + case NFTA_NAT_REG_PROTO_MIN: + case NFTA_NAT_REG_PROTO_MAX: + if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0) { + perror("mnl_attr_validate"); + return MNL_CB_ERROR; + } + break; + } + + tb[type] = attr; + return MNL_CB_OK; +} + +static int +nft_rule_expr_nat_parse(struct nft_rule_expr *e, struct nlattr *attr) +{ + struct nft_expr_nat *nat = (struct nft_expr_nat *)e->data; + struct nlattr *tb[NFTA_NAT_MAX+1] = {}; + + if (mnl_attr_parse_nested(attr, nft_rule_expr_nat_cb, tb) < 0) + return -1; + + if (tb[NFTA_NAT_TYPE]) { + nat->type = ntohl(mnl_attr_get_u32(tb[NFTA_NAT_TYPE])); + e->flags |= (1 << NFT_EXPR_NAT_TYPE); + } + if (tb[NFTA_NAT_FAMILY]) { + nat->family = ntohl(mnl_attr_get_u32(tb[NFTA_NAT_FAMILY])); + e->flags |= (1 << NFT_EXPR_NAT_FAMILY); + } + if (tb[NFTA_NAT_REG_ADDR_MIN]) { + nat->sreg_addr_min = + ntohl(mnl_attr_get_u32(tb[NFTA_NAT_REG_ADDR_MIN])); + e->flags |= (1 << NFT_EXPR_NAT_REG_ADDR_MIN); + } + if (tb[NFTA_NAT_REG_ADDR_MAX]) { + nat->sreg_addr_max = + ntohl(mnl_attr_get_u32(tb[NFTA_NAT_REG_ADDR_MAX])); + e->flags |= (1 << NFT_EXPR_NAT_REG_ADDR_MAX); + } + if (tb[NFTA_NAT_REG_PROTO_MIN]) { + nat->sreg_proto_min = + ntohl(mnl_attr_get_u32(tb[NFTA_NAT_REG_PROTO_MIN])); + e->flags |= (1 << NFT_EXPR_NAT_REG_PROTO_MIN); + } + if (tb[NFTA_NAT_REG_PROTO_MAX]) { + nat->sreg_proto_max = + ntohl(mnl_attr_get_u32(tb[NFTA_NAT_REG_PROTO_MAX])); + e->flags |= (1 << NFT_EXPR_NAT_REG_PROTO_MAX); + } + + return 0; +} + +static void +nft_rule_expr_nat_build(struct nlmsghdr *nlh, struct nft_rule_expr *e) +{ + struct nft_expr_nat *nat = (struct nft_expr_nat *)e->data; + + if (e->flags & (1 << NFT_EXPR_NAT_TYPE)) + mnl_attr_put_u32(nlh, NFTA_NAT_TYPE, htonl(nat->type)); + if (e->flags & (1 << NFT_EXPR_NAT_FAMILY)) + mnl_attr_put_u32(nlh, NFTA_NAT_FAMILY, htonl(nat->family)); + if (e->flags & (1 << NFT_EXPR_NAT_REG_ADDR_MIN)) + mnl_attr_put_u32(nlh, NFTA_NAT_REG_ADDR_MIN, + htonl(nat->sreg_addr_min)); + if (e->flags & (1 << NFT_EXPR_NAT_REG_ADDR_MAX)) + mnl_attr_put_u32(nlh, NFTA_NAT_REG_ADDR_MAX, + htonl(nat->sreg_addr_max)); + if (e->flags & (1 << NFT_EXPR_NAT_REG_PROTO_MIN)) + mnl_attr_put_u32(nlh, NFTA_NAT_REG_PROTO_MIN, + htonl(nat->sreg_proto_min)); + if (e->flags & (1 << NFT_EXPR_NAT_REG_PROTO_MAX)) + mnl_attr_put_u32(nlh, NFTA_NAT_REG_PROTO_MAX, + htonl(nat->sreg_proto_max)); +} + +static int +nft_rule_expr_nat_snprintf(char *buf, size_t size, struct nft_rule_expr *e) +{ + struct nft_expr_nat *nat = (struct nft_expr_nat *)e->data; + int len = size, offset = 0, ret = 0; + + switch (nat->type) { + case NFT_NAT_SNAT: + ret = snprintf(buf, len, "type=NFT_NAT_SNAT "); + break; + case NFT_NAT_DNAT: + ret = snprintf(buf, len, "type=NFT_NAT_DNAT "); + break; + } + SNPRINTF_BUFFER_SIZE(ret, size, len, offset); + + ret = snprintf(buf, len, "family=%s ", + nat->family == AF_INET ? "AF_INET" : "AF_INET6"); + SNPRINTF_BUFFER_SIZE(ret, size, len, offset); + + if (e->flags & (1 << NFT_EXPR_NAT_REG_ADDR_MIN)) { + ret = snprintf(buf, len, + "sreg_addr_min_v4=%u sreg_addr_max_v4=%u ", + nat->sreg_addr_min, nat->sreg_addr_max); + } + + SNPRINTF_BUFFER_SIZE(ret, size, len, offset); + + if (e->flags & (1 << NFT_EXPR_NAT_REG_PROTO_MIN)) { + ret = snprintf(buf, len, + "sreg_proto_min=%u sreg_proto_max=%u ", + nat->sreg_proto_min, nat->sreg_proto_max); + } + SNPRINTF_BUFFER_SIZE(ret, size, len, offset); + + return offset; +} + +struct expr_ops expr_ops_nat = { + .name = "nat", + .alloc_len = sizeof(struct nft_expr_nat), + .max_attr = NFTA_NAT_MAX, + .set = nft_rule_expr_nat_set, + .get = nft_rule_expr_nat_get, + .parse = nft_rule_expr_nat_parse, + .build = nft_rule_expr_nat_build, + .snprintf = nft_rule_expr_nat_snprintf, +}; diff --git a/src/expr_ops.c b/src/expr_ops.c index 9d121a0..6a5a697 100644 --- a/src/expr_ops.c +++ b/src/expr_ops.c @@ -8,6 +8,7 @@ extern struct expr_ops expr_ops_counter; extern struct expr_ops expr_ops_immediate; extern struct expr_ops expr_ops_match; extern struct expr_ops expr_ops_meta; +extern struct expr_ops expr_ops_nat; extern struct expr_ops expr_ops_payload; extern struct expr_ops expr_ops_target; @@ -18,6 +19,7 @@ struct expr_ops *expr_ops[] = { &expr_ops_immediate, &expr_ops_match, &expr_ops_meta, + &expr_ops_nat, &expr_ops_payload, &expr_ops_target, NULL, -- cgit v1.2.3