diff options
| -rw-r--r-- | include/buffer.h | 1 | ||||
| -rw-r--r-- | include/libnftnl/expr.h | 5 | ||||
| -rw-r--r-- | include/linux/netfilter/nf_tables.h | 21 | ||||
| -rw-r--r-- | src/Makefile.am | 1 | ||||
| -rw-r--r-- | src/expr/connlimit.c | 207 | ||||
| -rw-r--r-- | src/expr_ops.c | 2 |
6 files changed, 236 insertions, 1 deletions
diff --git a/include/buffer.h b/include/buffer.h index f556895..f6626a6 100644 --- a/include/buffer.h +++ b/include/buffer.h @@ -50,6 +50,7 @@ int nftnl_buf_expr(struct nftnl_buf *b, int type, uint32_t flags, #define COMPAT_FLAGS "compat_flags" #define COMPAT_PROTO "compat_proto" #define CONSUMED "consumed" +#define COUNT "count" #define DATA "data" #define DEVICE "device" #define DIR "dir" diff --git a/include/libnftnl/expr.h b/include/libnftnl/expr.h index 3dcd7dc..7d222af 100644 --- a/include/libnftnl/expr.h +++ b/include/libnftnl/expr.h @@ -103,6 +103,11 @@ enum { }; enum { + NFTNL_EXPR_CONNLIMIT_COUNT = NFTNL_EXPR_BASE, + NFTNL_EXPR_CONNLIMIT_FLAGS, +}; + +enum { NFTNL_EXPR_BITWISE_SREG = NFTNL_EXPR_BASE, NFTNL_EXPR_BITWISE_DREG, NFTNL_EXPR_BITWISE_LEN, diff --git a/include/linux/netfilter/nf_tables.h b/include/linux/netfilter/nf_tables.h index db80d53..e8f4b58 100644 --- a/include/linux/netfilter/nf_tables.h +++ b/include/linux/netfilter/nf_tables.h @@ -1043,6 +1043,24 @@ enum nft_limit_attributes { }; #define NFTA_LIMIT_MAX (__NFTA_LIMIT_MAX - 1) +enum nft_connlimit_flags { + NFT_CONNLIMIT_F_INV = (1 << 0), +}; + +/** + * enum nft_connlimit_attributes - nf_tables connlimit expression netlink attributes + * + * @NFTA_CONNLIMIT_COUNT: number of connections (NLA_U32) + * @NFTA_CONNLIMIT_FLAGS: flags (NLA_U32: enum nft_connlimit_flags) + */ +enum nft_connlimit_attributes { + NFTA_CONNLIMIT_UNSPEC, + NFTA_CONNLIMIT_COUNT, + NFTA_CONNLIMIT_FLAGS, + __NFTA_CONNLIMIT_MAX +}; +#define NFTA_CONNLIMIT_MAX (__NFTA_CONNLIMIT_MAX - 1) + /** * enum nft_counter_attributes - nf_tables counter expression netlink attributes * @@ -1348,7 +1366,8 @@ enum nft_ct_helper_attributes { #define NFT_OBJECT_QUOTA 2 #define NFT_OBJECT_CT_HELPER 3 #define NFT_OBJECT_LIMIT 4 -#define __NFT_OBJECT_MAX 5 +#define NFT_OBJECT_CONNLIMIT 5 +#define __NFT_OBJECT_MAX 6 #define NFT_OBJECT_MAX (__NFT_OBJECT_MAX - 1) /** diff --git a/src/Makefile.am b/src/Makefile.am index cd06372..c66a257 100644 --- a/src/Makefile.am +++ b/src/Makefile.am @@ -27,6 +27,7 @@ libnftnl_la_SOURCES = utils.c \ expr/byteorder.c \ expr/cmp.c \ expr/range.c \ + expr/connlimit.c \ expr/counter.c \ expr/ct.c \ expr/data_reg.c \ diff --git a/src/expr/connlimit.c b/src/expr/connlimit.c new file mode 100644 index 0000000..60965b5 --- /dev/null +++ b/src/expr/connlimit.c @@ -0,0 +1,207 @@ +/* + * (C) 2018 by Pablo Neira Ayuso <pablo@netfilter.org> + * + * 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 <stdio.h> +#include <stdint.h> +#include <arpa/inet.h> +#include <errno.h> +#include <inttypes.h> + +#include <linux/netfilter/nf_tables.h> + +#include "internal.h" +#include <libmnl/libmnl.h> +#include <libnftnl/expr.h> +#include <libnftnl/rule.h> + +struct nftnl_expr_connlimit { + uint32_t count; + uint32_t flags; +}; + +static int +nftnl_expr_connlimit_set(struct nftnl_expr *e, uint16_t type, + const void *data, uint32_t data_len) +{ + struct nftnl_expr_connlimit *connlimit = nftnl_expr_data(e); + + switch(type) { + case NFTNL_EXPR_CONNLIMIT_COUNT: + connlimit->count = *((uint32_t *)data); + break; + case NFTNL_EXPR_CONNLIMIT_FLAGS: + connlimit->flags = *((uint32_t *)data); + break; + default: + return -1; + } + return 0; +} + +static const void * +nftnl_expr_connlimit_get(const struct nftnl_expr *e, uint16_t type, + uint32_t *data_len) +{ + struct nftnl_expr_connlimit *connlimit = nftnl_expr_data(e); + + switch(type) { + case NFTNL_EXPR_CONNLIMIT_COUNT: + *data_len = sizeof(connlimit->count); + return &connlimit->count; + case NFTNL_EXPR_CONNLIMIT_FLAGS: + *data_len = sizeof(connlimit->flags); + return &connlimit->flags; + } + return NULL; +} + +static int nftnl_expr_connlimit_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_CONNLIMIT_MAX) < 0) + return MNL_CB_OK; + + switch(type) { + case NFTA_CONNLIMIT_COUNT: + case NFTA_CONNLIMIT_FLAGS: + if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0) + abi_breakage(); + break; + } + + tb[type] = attr; + return MNL_CB_OK; +} + +static void +nftnl_expr_connlimit_build(struct nlmsghdr *nlh, const struct nftnl_expr *e) +{ + struct nftnl_expr_connlimit *connlimit = nftnl_expr_data(e); + + if (e->flags & (1 << NFTNL_EXPR_CONNLIMIT_COUNT)) + mnl_attr_put_u32(nlh, NFTA_CONNLIMIT_COUNT, + htonl(connlimit->count)); + if (e->flags & (1 << NFTNL_EXPR_CONNLIMIT_FLAGS)) + mnl_attr_put_u32(nlh, NFTA_CONNLIMIT_FLAGS, + htonl(connlimit->flags)); +} + +static int +nftnl_expr_connlimit_parse(struct nftnl_expr *e, struct nlattr *attr) +{ + struct nftnl_expr_connlimit *connlimit = nftnl_expr_data(e); + struct nlattr *tb[NFTA_CONNLIMIT_MAX+1] = {}; + + if (mnl_attr_parse_nested(attr, nftnl_expr_connlimit_cb, tb) < 0) + return -1; + + if (tb[NFTA_CONNLIMIT_COUNT]) { + connlimit->count = + ntohl(mnl_attr_get_u32(tb[NFTA_CONNLIMIT_COUNT])); + e->flags |= (1 << NFTNL_EXPR_CONNLIMIT_COUNT); + } + if (tb[NFTA_CONNLIMIT_FLAGS]) { + connlimit->flags = + ntohl(mnl_attr_get_u32(tb[NFTA_CONNLIMIT_FLAGS])); + e->flags |= (1 << NFTNL_EXPR_CONNLIMIT_FLAGS); + } + + return 0; +} + +static int +nftnl_expr_connlimit_json_parse(struct nftnl_expr *e, json_t *root, + struct nftnl_parse_err *err) +{ +#ifdef JSON_PARSING + uint32_t uval32; + + if (nftnl_jansson_parse_val(root, "count", NFTNL_TYPE_U32, &uval32, + err) == 0) + nftnl_expr_set_u32(e, NFTNL_EXPR_CONNLIMIT_COUNT, uval32); + + if (nftnl_jansson_parse_val(root, "flags", NFTNL_TYPE_U32, &uval32, + err) == 0) + nftnl_expr_set_u32(e, NFTNL_EXPR_CONNLIMIT_FLAGS, uval32); + + return 0; +#else + errno = EOPNOTSUPP; + return -1; +#endif +} + +static int nftnl_expr_connlimit_export(char *buf, size_t size, + const struct nftnl_expr *e, int type) +{ + struct nftnl_expr_connlimit *connlimit = nftnl_expr_data(e); + NFTNL_BUF_INIT(b, buf, size); + + if (e->flags & (1 << NFTNL_EXPR_CONNLIMIT_COUNT)) + nftnl_buf_u32(&b, type, connlimit->count, COUNT); + if (e->flags & (1 << NFTNL_EXPR_CONNLIMIT_FLAGS)) + nftnl_buf_u32(&b, type, connlimit->flags, FLAGS); + + return nftnl_buf_done(&b); +} + +static int nftnl_expr_connlimit_snprintf_default(char *buf, size_t len, + const struct nftnl_expr *e) +{ + struct nftnl_expr_connlimit *connlimit = nftnl_expr_data(e); + + return snprintf(buf, len, "count %u flags %x ", + connlimit->count, connlimit->flags); +} + +static int nftnl_expr_connlimit_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_connlimit_snprintf_default(buf, len, e); + case NFTNL_OUTPUT_XML: + case NFTNL_OUTPUT_JSON: + return nftnl_expr_connlimit_export(buf, len, e, type); + default: + break; + } + return -1; +} + +static bool nftnl_expr_connlimit_cmp(const struct nftnl_expr *e1, + const struct nftnl_expr *e2) +{ + struct nftnl_expr_connlimit *c1 = nftnl_expr_data(e1); + struct nftnl_expr_connlimit *c2 = nftnl_expr_data(e2); + bool eq = true; + + if (e1->flags & (1 << NFTNL_EXPR_CONNLIMIT_COUNT)) + eq &= (c1->count == c2->count); + if (e1->flags & (1 << NFTNL_EXPR_CONNLIMIT_FLAGS)) + eq &= (c1->flags == c2->flags); + + return eq; +} + +struct expr_ops expr_ops_connlimit = { + .name = "connlimit", + .alloc_len = sizeof(struct nftnl_expr_connlimit), + .max_attr = NFTA_CONNLIMIT_MAX, + .cmp = nftnl_expr_connlimit_cmp, + .set = nftnl_expr_connlimit_set, + .get = nftnl_expr_connlimit_get, + .parse = nftnl_expr_connlimit_parse, + .build = nftnl_expr_connlimit_build, + .snprintf = nftnl_expr_connlimit_snprintf, + .json_parse = nftnl_expr_connlimit_json_parse, +}; diff --git a/src/expr_ops.c b/src/expr_ops.c index 9df55fd..cbb2a1b 100644 --- a/src/expr_ops.c +++ b/src/expr_ops.c @@ -7,6 +7,7 @@ extern struct expr_ops expr_ops_bitwise; extern struct expr_ops expr_ops_byteorder; extern struct expr_ops expr_ops_cmp; +extern struct expr_ops expr_ops_connlimit; extern struct expr_ops expr_ops_counter; extern struct expr_ops expr_ops_ct; extern struct expr_ops expr_ops_dup; @@ -44,6 +45,7 @@ static struct expr_ops *expr_ops[] = { &expr_ops_bitwise, &expr_ops_byteorder, &expr_ops_cmp, + &expr_ops_connlimit, &expr_ops_counter, &expr_ops_ct, &expr_ops_dup, |