netfilter: nf_tables: nat: merge nft_masq protocol specific modules

The family specific masq modules are way too small to warrant
an extra module, just place all of them in nft_masq.

before:
  text	   data	    bss	    dec	    hex	filename
   1001	    832	      0	   1833	    729	nft_masq.ko
    766	    896	      0	   1662	    67e	nft_masq_ipv4.ko
    764	    896	      0	   1660	    67c	nft_masq_ipv6.ko

after:
   2010	    960	      0	   2970	    b9a	nft_masq.ko

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

2 files changed, 168 insertions, 13 deletions

diff --git a/net/netfilter/Kconfig b/net/netfilter/Kconfig
index 73857f9fdb25..537f23a8ed52 100644
--- a/net/netfilter/Kconfig
+++ b/net/netfilter/Kconfig
@@ -532,6 +532,7 @@ config NFT_LIMIT
 config NFT_MASQ
 	depends on NF_CONNTRACK
 	depends on NF_NAT
+	select NF_NAT_MASQUERADE
 	tristate "Netfilter nf_tables masquerade support"
 	help
 	  This option adds the "masquerade" expression that you can use
diff --git a/net/netfilter/nft_masq.c b/net/netfilter/nft_masq.c
index 9d8655bc1bea..bee156eaa400 100644
--- a/net/netfilter/nft_masq.c
+++ b/net/netfilter/nft_masq.c
@@ -14,18 +14,24 @@
 #include <linux/netfilter/nf_tables.h>
 #include <net/netfilter/nf_tables.h>
 #include <net/netfilter/nf_nat.h>
-#include <net/netfilter/nft_masq.h>
+#include <net/netfilter/ipv4/nf_nat_masquerade.h>
+#include <net/netfilter/ipv6/nf_nat_masquerade.h>
 
-const struct nla_policy nft_masq_policy[NFTA_MASQ_MAX + 1] = {
+struct nft_masq {
+	u32			flags;
+	enum nft_registers      sreg_proto_min:8;
+	enum nft_registers      sreg_proto_max:8;
+};
+
+static const struct nla_policy nft_masq_policy[NFTA_MASQ_MAX + 1] = {
 	[NFTA_MASQ_FLAGS]		= { .type = NLA_U32 },
 	[NFTA_MASQ_REG_PROTO_MIN]	= { .type = NLA_U32 },
 	[NFTA_MASQ_REG_PROTO_MAX]	= { .type = NLA_U32 },
 };
-EXPORT_SYMBOL_GPL(nft_masq_policy);
 
-int nft_masq_validate(const struct nft_ctx *ctx,
-		      const struct nft_expr *expr,
-		      const struct nft_data **data)
+static int nft_masq_validate(const struct nft_ctx *ctx,
+			     const struct nft_expr *expr,
+			     const struct nft_data **data)
 {
 	int err;
 
@@ -36,11 +42,10 @@ int nft_masq_validate(const struct nft_ctx *ctx,
 	return nft_chain_validate_hooks(ctx->chain,
 				        (1 << NF_INET_POST_ROUTING));
 }
-EXPORT_SYMBOL_GPL(nft_masq_validate);
 
-int nft_masq_init(const struct nft_ctx *ctx,
-		  const struct nft_expr *expr,
-		  const struct nlattr * const tb[])
+static int nft_masq_init(const struct nft_ctx *ctx,
+			 const struct nft_expr *expr,
+			 const struct nlattr * const tb[])
 {
 	u32 plen = FIELD_SIZEOF(struct nf_nat_range, min_addr.all);
 	struct nft_masq *priv = nft_expr_priv(expr);
@@ -75,9 +80,8 @@ int nft_masq_init(const struct nft_ctx *ctx,
 
 	return nf_ct_netns_get(ctx->net, ctx->family);
 }
-EXPORT_SYMBOL_GPL(nft_masq_init);
 
-int nft_masq_dump(struct sk_buff *skb, const struct nft_expr *expr)
+static int nft_masq_dump(struct sk_buff *skb, const struct nft_expr *expr)
 {
 	const struct nft_masq *priv = nft_expr_priv(expr);
 
@@ -98,7 +102,157 @@ int nft_masq_dump(struct sk_buff *skb, const struct nft_expr *expr)
 nla_put_failure:
 	return -1;
 }
-EXPORT_SYMBOL_GPL(nft_masq_dump);
+
+static void nft_masq_ipv4_eval(const struct nft_expr *expr,
+			       struct nft_regs *regs,
+			       const struct nft_pktinfo *pkt)
+{
+	struct nft_masq *priv = nft_expr_priv(expr);
+	struct nf_nat_range2 range;
+
+	memset(&range, 0, sizeof(range));
+	range.flags = priv->flags;
+	if (priv->sreg_proto_min) {
+		range.min_proto.all = (__force __be16)nft_reg_load16(
+			&regs->data[priv->sreg_proto_min]);
+		range.max_proto.all = (__force __be16)nft_reg_load16(
+			&regs->data[priv->sreg_proto_max]);
+	}
+	regs->verdict.code = nf_nat_masquerade_ipv4(pkt->skb, nft_hook(pkt),
+						    &range, nft_out(pkt));
+}
+
+static void
+nft_masq_ipv4_destroy(const struct nft_ctx *ctx, const struct nft_expr *expr)
+{
+	nf_ct_netns_put(ctx->net, NFPROTO_IPV4);
+}
+
+static struct nft_expr_type nft_masq_ipv4_type;
+static const struct nft_expr_ops nft_masq_ipv4_ops = {
+	.type		= &nft_masq_ipv4_type,
+	.size		= NFT_EXPR_SIZE(sizeof(struct nft_masq)),
+	.eval		= nft_masq_ipv4_eval,
+	.init		= nft_masq_init,
+	.destroy	= nft_masq_ipv4_destroy,
+	.dump		= nft_masq_dump,
+	.validate	= nft_masq_validate,
+};
+
+static struct nft_expr_type nft_masq_ipv4_type __read_mostly = {
+	.family		= NFPROTO_IPV4,
+	.name		= "masq",
+	.ops		= &nft_masq_ipv4_ops,
+	.policy		= nft_masq_policy,
+	.maxattr	= NFTA_MASQ_MAX,
+	.owner		= THIS_MODULE,
+};
+
+#ifdef CONFIG_NF_TABLES_IPV6
+static void nft_masq_ipv6_eval(const struct nft_expr *expr,
+			       struct nft_regs *regs,
+			       const struct nft_pktinfo *pkt)
+{
+	struct nft_masq *priv = nft_expr_priv(expr);
+	struct nf_nat_range2 range;
+
+	memset(&range, 0, sizeof(range));
+	range.flags = priv->flags;
+	if (priv->sreg_proto_min) {
+		range.min_proto.all = (__force __be16)nft_reg_load16(
+			&regs->data[priv->sreg_proto_min]);
+		range.max_proto.all = (__force __be16)nft_reg_load16(
+			&regs->data[priv->sreg_proto_max]);
+	}
+	regs->verdict.code = nf_nat_masquerade_ipv6(pkt->skb, &range,
+						    nft_out(pkt));
+}
+
+static void
+nft_masq_ipv6_destroy(const struct nft_ctx *ctx, const struct nft_expr *expr)
+{
+	nf_ct_netns_put(ctx->net, NFPROTO_IPV6);
+}
+
+static struct nft_expr_type nft_masq_ipv6_type;
+static const struct nft_expr_ops nft_masq_ipv6_ops = {
+	.type		= &nft_masq_ipv6_type,
+	.size		= NFT_EXPR_SIZE(sizeof(struct nft_masq)),
+	.eval		= nft_masq_ipv6_eval,
+	.init		= nft_masq_init,
+	.destroy	= nft_masq_ipv6_destroy,
+	.dump		= nft_masq_dump,
+	.validate	= nft_masq_validate,
+};
+
+static struct nft_expr_type nft_masq_ipv6_type __read_mostly = {
+	.family		= NFPROTO_IPV6,
+	.name		= "masq",
+	.ops		= &nft_masq_ipv6_ops,
+	.policy		= nft_masq_policy,
+	.maxattr	= NFTA_MASQ_MAX,
+	.owner		= THIS_MODULE,
+};
+
+static int __init nft_masq_module_init_ipv6(void)
+{
+	int ret = nft_register_expr(&nft_masq_ipv6_type);
+
+	if (ret)
+		return ret;
+
+	ret = nf_nat_masquerade_ipv6_register_notifier();
+	if (ret < 0)
+		nft_unregister_expr(&nft_masq_ipv6_type);
+
+	return ret;
+}
+
+static void nft_masq_module_exit_ipv6(void)
+{
+	nft_unregister_expr(&nft_masq_ipv6_type);
+	nf_nat_masquerade_ipv6_unregister_notifier();
+}
+#else
+static inline int nft_masq_module_init_ipv6(void) { return 0; }
+static inline void nft_masq_module_exit_ipv6(void) {}
+#endif
+
+static int __init nft_masq_module_init(void)
+{
+	int ret;
+
+	ret = nft_masq_module_init_ipv6();
+	if (ret < 0)
+		return ret;
+
+	ret = nft_register_expr(&nft_masq_ipv4_type);
+	if (ret < 0) {
+		nft_masq_module_exit_ipv6();
+		return ret;
+	}
+
+	ret = nf_nat_masquerade_ipv4_register_notifier();
+	if (ret < 0) {
+		nft_masq_module_exit_ipv6();
+		nft_unregister_expr(&nft_masq_ipv4_type);
+		return ret;
+	}
+
+	return ret;
+}
+
+static void __exit nft_masq_module_exit(void)
+{
+	nft_masq_module_exit_ipv6();
+	nft_unregister_expr(&nft_masq_ipv4_type);
+	nf_nat_masquerade_ipv4_unregister_notifier();
+}
+
+module_init(nft_masq_module_init);
+module_exit(nft_masq_module_exit);
 
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Arturo Borrero Gonzalez <arturo@debian.org>");
+MODULE_ALIAS_NFT_AF_EXPR(AF_INET6, "masq");
+MODULE_ALIAS_NFT_AF_EXPR(AF_INET, "masq");