From ace9429bb58fd418f0c81d4c2835699bddf6bde6 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Thu, 11 Apr 2024 10:27:49 +0200 Subject: Adding upstream version 6.6.15. Signed-off-by: Daniel Baumann --- net/netfilter/nft_nat.c | 407 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 407 insertions(+) create mode 100644 net/netfilter/nft_nat.c (limited to 'net/netfilter/nft_nat.c') diff --git a/net/netfilter/nft_nat.c b/net/netfilter/nft_nat.c new file mode 100644 index 000000000..808f5802c --- /dev/null +++ b/net/netfilter/nft_nat.c @@ -0,0 +1,407 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2008-2009 Patrick McHardy + * Copyright (c) 2012 Pablo Neira Ayuso + * Copyright (c) 2012 Intel Corporation + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +struct nft_nat { + u8 sreg_addr_min; + u8 sreg_addr_max; + u8 sreg_proto_min; + u8 sreg_proto_max; + enum nf_nat_manip_type type:8; + u8 family; + u16 flags; +}; + +static void nft_nat_setup_addr(struct nf_nat_range2 *range, + const struct nft_regs *regs, + const struct nft_nat *priv) +{ + switch (priv->family) { + case AF_INET: + range->min_addr.ip = (__force __be32) + regs->data[priv->sreg_addr_min]; + range->max_addr.ip = (__force __be32) + regs->data[priv->sreg_addr_max]; + break; + case AF_INET6: + memcpy(range->min_addr.ip6, ®s->data[priv->sreg_addr_min], + sizeof(range->min_addr.ip6)); + memcpy(range->max_addr.ip6, ®s->data[priv->sreg_addr_max], + sizeof(range->max_addr.ip6)); + break; + } +} + +static void nft_nat_setup_proto(struct nf_nat_range2 *range, + const struct nft_regs *regs, + const struct nft_nat *priv) +{ + range->min_proto.all = (__force __be16) + nft_reg_load16(®s->data[priv->sreg_proto_min]); + range->max_proto.all = (__force __be16) + nft_reg_load16(®s->data[priv->sreg_proto_max]); +} + +static void nft_nat_setup_netmap(struct nf_nat_range2 *range, + const struct nft_pktinfo *pkt, + const struct nft_nat *priv) +{ + struct sk_buff *skb = pkt->skb; + union nf_inet_addr new_addr; + __be32 netmask; + int i, len = 0; + + switch (priv->type) { + case NFT_NAT_SNAT: + if (nft_pf(pkt) == NFPROTO_IPV4) { + new_addr.ip = ip_hdr(skb)->saddr; + len = sizeof(struct in_addr); + } else { + new_addr.in6 = ipv6_hdr(skb)->saddr; + len = sizeof(struct in6_addr); + } + break; + case NFT_NAT_DNAT: + if (nft_pf(pkt) == NFPROTO_IPV4) { + new_addr.ip = ip_hdr(skb)->daddr; + len = sizeof(struct in_addr); + } else { + new_addr.in6 = ipv6_hdr(skb)->daddr; + len = sizeof(struct in6_addr); + } + break; + } + + for (i = 0; i < len / sizeof(__be32); i++) { + netmask = ~(range->min_addr.ip6[i] ^ range->max_addr.ip6[i]); + new_addr.ip6[i] &= ~netmask; + new_addr.ip6[i] |= range->min_addr.ip6[i] & netmask; + } + + range->min_addr = new_addr; + range->max_addr = new_addr; +} + +static void nft_nat_eval(const struct nft_expr *expr, + struct nft_regs *regs, + const struct nft_pktinfo *pkt) +{ + const struct nft_nat *priv = nft_expr_priv(expr); + enum ip_conntrack_info ctinfo; + struct nf_conn *ct = nf_ct_get(pkt->skb, &ctinfo); + struct nf_nat_range2 range; + + memset(&range, 0, sizeof(range)); + + if (priv->sreg_addr_min) { + nft_nat_setup_addr(&range, regs, priv); + if (priv->flags & NF_NAT_RANGE_NETMAP) + nft_nat_setup_netmap(&range, pkt, priv); + } + + if (priv->sreg_proto_min) + nft_nat_setup_proto(&range, regs, priv); + + range.flags = priv->flags; + + regs->verdict.code = nf_nat_setup_info(ct, &range, priv->type); +} + +static const struct nla_policy nft_nat_policy[NFTA_NAT_MAX + 1] = { + [NFTA_NAT_TYPE] = { .type = NLA_U32 }, + [NFTA_NAT_FAMILY] = { .type = NLA_U32 }, + [NFTA_NAT_REG_ADDR_MIN] = { .type = NLA_U32 }, + [NFTA_NAT_REG_ADDR_MAX] = { .type = NLA_U32 }, + [NFTA_NAT_REG_PROTO_MIN] = { .type = NLA_U32 }, + [NFTA_NAT_REG_PROTO_MAX] = { .type = NLA_U32 }, + [NFTA_NAT_FLAGS] = + NLA_POLICY_MASK(NLA_BE32, NF_NAT_RANGE_MASK), +}; + +static int nft_nat_validate(const struct nft_ctx *ctx, + const struct nft_expr *expr, + const struct nft_data **data) +{ + struct nft_nat *priv = nft_expr_priv(expr); + int err; + + if (ctx->family != NFPROTO_IPV4 && + ctx->family != NFPROTO_IPV6 && + ctx->family != NFPROTO_INET) + return -EOPNOTSUPP; + + err = nft_chain_validate_dependency(ctx->chain, NFT_CHAIN_T_NAT); + if (err < 0) + return err; + + switch (priv->type) { + case NFT_NAT_SNAT: + err = nft_chain_validate_hooks(ctx->chain, + (1 << NF_INET_POST_ROUTING) | + (1 << NF_INET_LOCAL_IN)); + break; + case NFT_NAT_DNAT: + err = nft_chain_validate_hooks(ctx->chain, + (1 << NF_INET_PRE_ROUTING) | + (1 << NF_INET_LOCAL_OUT)); + break; + } + + return err; +} + +static int nft_nat_init(const struct nft_ctx *ctx, const struct nft_expr *expr, + const struct nlattr * const tb[]) +{ + struct nft_nat *priv = nft_expr_priv(expr); + unsigned int alen, plen; + u32 family; + int err; + + if (tb[NFTA_NAT_TYPE] == NULL || + (tb[NFTA_NAT_REG_ADDR_MIN] == NULL && + tb[NFTA_NAT_REG_PROTO_MIN] == NULL)) + return -EINVAL; + + switch (ntohl(nla_get_be32(tb[NFTA_NAT_TYPE]))) { + case NFT_NAT_SNAT: + priv->type = NF_NAT_MANIP_SRC; + break; + case NFT_NAT_DNAT: + priv->type = NF_NAT_MANIP_DST; + break; + default: + return -EOPNOTSUPP; + } + + if (tb[NFTA_NAT_FAMILY] == NULL) + return -EINVAL; + + family = ntohl(nla_get_be32(tb[NFTA_NAT_FAMILY])); + if (ctx->family != NFPROTO_INET && ctx->family != family) + return -EOPNOTSUPP; + + switch (family) { + case NFPROTO_IPV4: + alen = sizeof_field(struct nf_nat_range, min_addr.ip); + break; + case NFPROTO_IPV6: + alen = sizeof_field(struct nf_nat_range, min_addr.ip6); + break; + default: + if (tb[NFTA_NAT_REG_ADDR_MIN]) + return -EAFNOSUPPORT; + break; + } + priv->family = family; + + if (tb[NFTA_NAT_REG_ADDR_MIN]) { + err = nft_parse_register_load(tb[NFTA_NAT_REG_ADDR_MIN], + &priv->sreg_addr_min, alen); + if (err < 0) + return err; + + if (tb[NFTA_NAT_REG_ADDR_MAX]) { + err = nft_parse_register_load(tb[NFTA_NAT_REG_ADDR_MAX], + &priv->sreg_addr_max, + alen); + if (err < 0) + return err; + } else { + priv->sreg_addr_max = priv->sreg_addr_min; + } + + priv->flags |= NF_NAT_RANGE_MAP_IPS; + } + + plen = sizeof_field(struct nf_nat_range, min_proto.all); + if (tb[NFTA_NAT_REG_PROTO_MIN]) { + err = nft_parse_register_load(tb[NFTA_NAT_REG_PROTO_MIN], + &priv->sreg_proto_min, plen); + if (err < 0) + return err; + + if (tb[NFTA_NAT_REG_PROTO_MAX]) { + err = nft_parse_register_load(tb[NFTA_NAT_REG_PROTO_MAX], + &priv->sreg_proto_max, + plen); + if (err < 0) + return err; + } else { + priv->sreg_proto_max = priv->sreg_proto_min; + } + + priv->flags |= NF_NAT_RANGE_PROTO_SPECIFIED; + } + + if (tb[NFTA_NAT_FLAGS]) + priv->flags |= ntohl(nla_get_be32(tb[NFTA_NAT_FLAGS])); + + return nf_ct_netns_get(ctx->net, family); +} + +static int nft_nat_dump(struct sk_buff *skb, + const struct nft_expr *expr, bool reset) +{ + const struct nft_nat *priv = nft_expr_priv(expr); + + switch (priv->type) { + case NF_NAT_MANIP_SRC: + if (nla_put_be32(skb, NFTA_NAT_TYPE, htonl(NFT_NAT_SNAT))) + goto nla_put_failure; + break; + case NF_NAT_MANIP_DST: + if (nla_put_be32(skb, NFTA_NAT_TYPE, htonl(NFT_NAT_DNAT))) + goto nla_put_failure; + break; + } + + if (nla_put_be32(skb, NFTA_NAT_FAMILY, htonl(priv->family))) + goto nla_put_failure; + + if (priv->sreg_addr_min) { + if (nft_dump_register(skb, NFTA_NAT_REG_ADDR_MIN, + priv->sreg_addr_min) || + nft_dump_register(skb, NFTA_NAT_REG_ADDR_MAX, + priv->sreg_addr_max)) + goto nla_put_failure; + } + + if (priv->sreg_proto_min) { + if (nft_dump_register(skb, NFTA_NAT_REG_PROTO_MIN, + priv->sreg_proto_min) || + nft_dump_register(skb, NFTA_NAT_REG_PROTO_MAX, + priv->sreg_proto_max)) + goto nla_put_failure; + } + + if (priv->flags != 0) { + if (nla_put_be32(skb, NFTA_NAT_FLAGS, htonl(priv->flags))) + goto nla_put_failure; + } + + return 0; + +nla_put_failure: + return -1; +} + +static void +nft_nat_destroy(const struct nft_ctx *ctx, const struct nft_expr *expr) +{ + const struct nft_nat *priv = nft_expr_priv(expr); + + nf_ct_netns_put(ctx->net, priv->family); +} + +static struct nft_expr_type nft_nat_type; +static const struct nft_expr_ops nft_nat_ops = { + .type = &nft_nat_type, + .size = NFT_EXPR_SIZE(sizeof(struct nft_nat)), + .eval = nft_nat_eval, + .init = nft_nat_init, + .destroy = nft_nat_destroy, + .dump = nft_nat_dump, + .validate = nft_nat_validate, + .reduce = NFT_REDUCE_READONLY, +}; + +static struct nft_expr_type nft_nat_type __read_mostly = { + .name = "nat", + .ops = &nft_nat_ops, + .policy = nft_nat_policy, + .maxattr = NFTA_NAT_MAX, + .owner = THIS_MODULE, +}; + +#ifdef CONFIG_NF_TABLES_INET +static void nft_nat_inet_eval(const struct nft_expr *expr, + struct nft_regs *regs, + const struct nft_pktinfo *pkt) +{ + const struct nft_nat *priv = nft_expr_priv(expr); + + if (priv->family == nft_pf(pkt) || + priv->family == NFPROTO_INET) + nft_nat_eval(expr, regs, pkt); +} + +static const struct nft_expr_ops nft_nat_inet_ops = { + .type = &nft_nat_type, + .size = NFT_EXPR_SIZE(sizeof(struct nft_nat)), + .eval = nft_nat_inet_eval, + .init = nft_nat_init, + .destroy = nft_nat_destroy, + .dump = nft_nat_dump, + .validate = nft_nat_validate, + .reduce = NFT_REDUCE_READONLY, +}; + +static struct nft_expr_type nft_inet_nat_type __read_mostly = { + .name = "nat", + .family = NFPROTO_INET, + .ops = &nft_nat_inet_ops, + .policy = nft_nat_policy, + .maxattr = NFTA_NAT_MAX, + .owner = THIS_MODULE, +}; + +static int nft_nat_inet_module_init(void) +{ + return nft_register_expr(&nft_inet_nat_type); +} + +static void nft_nat_inet_module_exit(void) +{ + nft_unregister_expr(&nft_inet_nat_type); +} +#else +static int nft_nat_inet_module_init(void) { return 0; } +static void nft_nat_inet_module_exit(void) { } +#endif + +static int __init nft_nat_module_init(void) +{ + int ret = nft_nat_inet_module_init(); + + if (ret) + return ret; + + ret = nft_register_expr(&nft_nat_type); + if (ret) + nft_nat_inet_module_exit(); + + return ret; +} + +static void __exit nft_nat_module_exit(void) +{ + nft_nat_inet_module_exit(); + nft_unregister_expr(&nft_nat_type); +} + +module_init(nft_nat_module_init); +module_exit(nft_nat_module_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Tomasz Bursztyka "); +MODULE_ALIAS_NFT_EXPR("nat"); +MODULE_DESCRIPTION("Network Address Translation support"); -- cgit v1.2.3