From d1fb9ccb094e6cb9d33c3eae427003c9aefb5c99 Mon Sep 17 00:00:00 2001 From: Syrone Wong Date: Fri, 8 Apr 2022 23:52:11 +0800 Subject: [PATCH 1/2] libnftnl: add fullcone expression support Signed-off-by: Syrone Wong --- include/libnftnl/expr.h | 6 + include/linux/netfilter/nf_tables.h | 16 +++ src/Makefile.am | 1 + src/expr/fullcone.c | 167 ++++++++++++++++++++++++++++ src/expr_ops.c | 2 + 5 files changed, 192 insertions(+) create mode 100644 src/expr/fullcone.c --- a/include/libnftnl/expr.h +++ b/include/libnftnl/expr.h @@ -272,6 +272,12 @@ enum { }; enum { + NFTNL_EXPR_FULLCONE_FLAGS = NFTNL_EXPR_BASE, + NFTNL_EXPR_FULLCONE_REG_PROTO_MIN, + NFTNL_EXPR_FULLCONE_REG_PROTO_MAX, +}; + +enum { NFTNL_EXPR_REDIR_REG_PROTO_MIN = NFTNL_EXPR_BASE, NFTNL_EXPR_REDIR_REG_PROTO_MAX, NFTNL_EXPR_REDIR_FLAGS, --- a/include/linux/netfilter/nf_tables.h +++ b/include/linux/netfilter/nf_tables.h @@ -1464,6 +1464,22 @@ enum nft_masq_attributes { #define NFTA_MASQ_MAX (__NFTA_MASQ_MAX - 1) /** + * enum nft_fullcone_attributes - nf_tables fullcone expression attributes + * + * @NFTA_FULLCONE_FLAGS: NAT flags (see NF_NAT_RANGE_* in linux/netfilter/nf_nat.h) (NLA_U32) + * @NFTA_FULLCONE_REG_PROTO_MIN: source register of proto range start (NLA_U32: nft_registers) + * @NFTA_FULLCONE_REG_PROTO_MAX: source register of proto range end (NLA_U32: nft_registers) + */ +enum nft_fullcone_attributes { + NFTA_FULLCONE_UNSPEC, + NFTA_FULLCONE_FLAGS, + NFTA_FULLCONE_REG_PROTO_MIN, + NFTA_FULLCONE_REG_PROTO_MAX, + __NFTA_FULLCONE_MAX +}; +#define NFTA_FULLCONE_MAX (__NFTA_FULLCONE_MAX - 1) + +/** * enum nft_redir_attributes - nf_tables redirect expression netlink attributes * * @NFTA_REDIR_REG_PROTO_MIN: source register of proto range start (NLA_U32: nft_registers) --- a/src/Makefile.am +++ b/src/Makefile.am @@ -55,6 +55,7 @@ libnftnl_la_SOURCES = utils.c \ expr/target.c \ expr/tunnel.c \ expr/masq.c \ + expr/fullcone.c \ expr/redir.c \ expr/hash.c \ expr/socket.c \ --- /dev/null +++ b/src/expr/fullcone.c @@ -0,0 +1,167 @@ +/* + * (C) 2022 wongsyrone + * + * 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_fullcone { + uint32_t flags; + enum nft_registers sreg_proto_min; + enum nft_registers sreg_proto_max; +}; + +static int +nftnl_expr_fullcone_set(struct nftnl_expr *e, uint16_t type, + const void *data, uint32_t data_len) +{ + struct nftnl_expr_fullcone *fullcone = nftnl_expr_data(e); + + switch (type) { + case NFTNL_EXPR_FULLCONE_FLAGS: + memcpy(&fullcone->flags, data, sizeof(fullcone->flags)); + break; + case NFTNL_EXPR_FULLCONE_REG_PROTO_MIN: + memcpy(&fullcone->sreg_proto_min, data, sizeof(fullcone->sreg_proto_min)); + break; + case NFTNL_EXPR_FULLCONE_REG_PROTO_MAX: + memcpy(&fullcone->sreg_proto_max, data, sizeof(fullcone->sreg_proto_max)); + break; + default: + return -1; + } + return 0; +} + +static const void * +nftnl_expr_fullcone_get(const struct nftnl_expr *e, uint16_t type, + uint32_t *data_len) +{ + struct nftnl_expr_fullcone *fullcone = nftnl_expr_data(e); + + switch (type) { + case NFTNL_EXPR_FULLCONE_FLAGS: + *data_len = sizeof(fullcone->flags); + return &fullcone->flags; + case NFTNL_EXPR_FULLCONE_REG_PROTO_MIN: + *data_len = sizeof(fullcone->sreg_proto_min); + return &fullcone->sreg_proto_min; + case NFTNL_EXPR_FULLCONE_REG_PROTO_MAX: + *data_len = sizeof(fullcone->sreg_proto_max); + return &fullcone->sreg_proto_max; + } + return NULL; +} + +static int nftnl_expr_fullcone_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_FULLCONE_MAX) < 0) + return MNL_CB_OK; + + switch (type) { + case NFTA_FULLCONE_REG_PROTO_MIN: + case NFTA_FULLCONE_REG_PROTO_MAX: + case NFTA_FULLCONE_FLAGS: + if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0) + abi_breakage(); + break; + } + + tb[type] = attr; + return MNL_CB_OK; +} + +static void +nftnl_expr_fullcone_build(struct nlmsghdr *nlh, const struct nftnl_expr *e) +{ + struct nftnl_expr_fullcone *fullcone = nftnl_expr_data(e); + + if (e->flags & (1 << NFTNL_EXPR_FULLCONE_FLAGS)) + mnl_attr_put_u32(nlh, NFTA_FULLCONE_FLAGS, htobe32(fullcone->flags)); + if (e->flags & (1 << NFTNL_EXPR_FULLCONE_REG_PROTO_MIN)) + mnl_attr_put_u32(nlh, NFTA_FULLCONE_REG_PROTO_MIN, + htobe32(fullcone->sreg_proto_min)); + if (e->flags & (1 << NFTNL_EXPR_FULLCONE_REG_PROTO_MAX)) + mnl_attr_put_u32(nlh, NFTA_FULLCONE_REG_PROTO_MAX, + htobe32(fullcone->sreg_proto_max)); +} + +static int +nftnl_expr_fullcone_parse(struct nftnl_expr *e, struct nlattr *attr) +{ + struct nftnl_expr_fullcone *fullcone = nftnl_expr_data(e); + struct nlattr *tb[NFTA_FULLCONE_MAX+1] = {}; + + if (mnl_attr_parse_nested(attr, nftnl_expr_fullcone_cb, tb) < 0) + return -1; + + if (tb[NFTA_FULLCONE_FLAGS]) { + fullcone->flags = be32toh(mnl_attr_get_u32(tb[NFTA_FULLCONE_FLAGS])); + e->flags |= (1 << NFTNL_EXPR_FULLCONE_FLAGS); + } + if (tb[NFTA_FULLCONE_REG_PROTO_MIN]) { + fullcone->sreg_proto_min = + be32toh(mnl_attr_get_u32(tb[NFTA_FULLCONE_REG_PROTO_MIN])); + e->flags |= (1 << NFTNL_EXPR_FULLCONE_REG_PROTO_MIN); + } + if (tb[NFTA_FULLCONE_REG_PROTO_MAX]) { + fullcone->sreg_proto_max = + be32toh(mnl_attr_get_u32(tb[NFTA_FULLCONE_REG_PROTO_MAX])); + e->flags |= (1 << NFTNL_EXPR_FULLCONE_REG_PROTO_MAX); + } + + return 0; +} + +static int nftnl_expr_fullcone_snprintf(char *buf, size_t remain, + uint32_t flags, const struct nftnl_expr *e) +{ + struct nftnl_expr_fullcone *fullcone = nftnl_expr_data(e); + int offset = 0, ret = 0; + + if (e->flags & (1 << NFTNL_EXPR_FULLCONE_REG_PROTO_MIN)) { + ret = snprintf(buf + offset, remain, "proto_min reg %u ", + fullcone->sreg_proto_min); + SNPRINTF_BUFFER_SIZE(ret, remain, offset); + } + if (e->flags & (1 << NFTNL_EXPR_FULLCONE_REG_PROTO_MAX)) { + ret = snprintf(buf + offset, remain, "proto_max reg %u ", + fullcone->sreg_proto_max); + SNPRINTF_BUFFER_SIZE(ret, remain, offset); + } + if (e->flags & (1 << NFTNL_EXPR_FULLCONE_FLAGS)) { + ret = snprintf(buf + offset, remain, "flags 0x%x ", fullcone->flags); + SNPRINTF_BUFFER_SIZE(ret, remain, offset); + } + + return offset; +} + +struct expr_ops expr_ops_fullcone = { + .name = "fullcone", + .alloc_len = sizeof(struct nftnl_expr_fullcone), + .nftnl_max_attr = NFTA_FULLCONE_MAX, + .set = nftnl_expr_fullcone_set, + .get = nftnl_expr_fullcone_get, + .parse = nftnl_expr_fullcone_parse, + .build = nftnl_expr_fullcone_build, + .output = nftnl_expr_fullcone_snprintf, +}; --- a/src/expr_ops.c +++ b/src/expr_ops.c @@ -20,6 +20,7 @@ extern struct expr_ops expr_ops_limit; extern struct expr_ops expr_ops_log; extern struct expr_ops expr_ops_lookup; extern struct expr_ops expr_ops_masq; +extern struct expr_ops expr_ops_fullcone; extern struct expr_ops expr_ops_match; extern struct expr_ops expr_ops_meta; extern struct expr_ops expr_ops_ng; @@ -65,6 +66,7 @@ static struct expr_ops *expr_ops[] = { &expr_ops_log, &expr_ops_lookup, &expr_ops_masq, + &expr_ops_fullcone, &expr_ops_match, &expr_ops_meta, &expr_ops_ng,