Initial import

1 files changed, 274 insertions, 0 deletions

diff --git a/net/netfilter/nf_tables_core.c b/net/netfilter/nf_tables_core.c
new file mode 100644
index 000000000..f153b0707
--- /dev/null
+++ b/net/netfilter/nf_tables_core.c
@@ -0,0 +1,274 @@
+/*
+ * Copyright (c) 2008 Patrick McHardy <kaber@trash.net>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Development of this code funded by Astaro AG (http://www.astaro.com/)
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/rculist.h>
+#include <linux/skbuff.h>
+#include <linux/netlink.h>
+#include <linux/netfilter.h>
+#include <linux/netfilter/nfnetlink.h>
+#include <linux/netfilter/nf_tables.h>
+#include <net/netfilter/nf_tables_core.h>
+#include <net/netfilter/nf_tables.h>
+#include <net/netfilter/nf_log.h>
+
+enum nft_trace {
+	NFT_TRACE_RULE,
+	NFT_TRACE_RETURN,
+	NFT_TRACE_POLICY,
+};
+
+static const char *const comments[] = {
+	[NFT_TRACE_RULE]	= "rule",
+	[NFT_TRACE_RETURN]	= "return",
+	[NFT_TRACE_POLICY]	= "policy",
+};
+
+static struct nf_loginfo trace_loginfo = {
+	.type = NF_LOG_TYPE_LOG,
+	.u = {
+		.log = {
+			.level = LOGLEVEL_WARNING,
+			.logflags = NF_LOG_MASK,
+	        },
+	},
+};
+
+static void __nft_trace_packet(const struct nft_pktinfo *pkt,
+			       const struct nft_chain *chain,
+			       int rulenum, enum nft_trace type)
+{
+	struct net *net = dev_net(pkt->in ? pkt->in : pkt->out);
+
+	nf_log_trace(net, pkt->xt.family, pkt->ops->hooknum, pkt->skb, pkt->in,
+		     pkt->out, &trace_loginfo, "TRACE: %s:%s:%s:%u ",
+		     chain->table->name, chain->name, comments[type],
+		     rulenum);
+}
+
+static inline void nft_trace_packet(const struct nft_pktinfo *pkt,
+				    const struct nft_chain *chain,
+				    int rulenum, enum nft_trace type)
+{
+	if (unlikely(pkt->skb->nf_trace))
+		__nft_trace_packet(pkt, chain, rulenum, type);
+}
+
+static void nft_cmp_fast_eval(const struct nft_expr *expr,
+			      struct nft_regs *regs)
+{
+	const struct nft_cmp_fast_expr *priv = nft_expr_priv(expr);
+	u32 mask = nft_cmp_fast_mask(priv->len);
+
+	if ((regs->data[priv->sreg] & mask) == priv->data)
+		return;
+	regs->verdict.code = NFT_BREAK;
+}
+
+static bool nft_payload_fast_eval(const struct nft_expr *expr,
+				  struct nft_regs *regs,
+				  const struct nft_pktinfo *pkt)
+{
+	const struct nft_payload *priv = nft_expr_priv(expr);
+	const struct sk_buff *skb = pkt->skb;
+	u32 *dest = &regs->data[priv->dreg];
+	unsigned char *ptr;
+
+	if (priv->base == NFT_PAYLOAD_NETWORK_HEADER)
+		ptr = skb_network_header(skb);
+	else
+		ptr = skb_network_header(skb) + pkt->xt.thoff;
+
+	ptr += priv->offset;
+
+	if (unlikely(ptr + priv->len >= skb_tail_pointer(skb)))
+		return false;
+
+	*dest = 0;
+	if (priv->len == 2)
+		*(u16 *)dest = *(u16 *)ptr;
+	else if (priv->len == 4)
+		*(u32 *)dest = *(u32 *)ptr;
+	else
+		*(u8 *)dest = *(u8 *)ptr;
+	return true;
+}
+
+struct nft_jumpstack {
+	const struct nft_chain	*chain;
+	const struct nft_rule	*rule;
+	int			rulenum;
+};
+
+unsigned int
+nft_do_chain(struct nft_pktinfo *pkt, const struct nf_hook_ops *ops)
+{
+	const struct nft_chain *chain = ops->priv, *basechain = chain;
+	const struct net *net = read_pnet(&nft_base_chain(basechain)->pnet);
+	const struct nft_rule *rule;
+	const struct nft_expr *expr, *last;
+	struct nft_regs regs;
+	unsigned int stackptr = 0;
+	struct nft_jumpstack jumpstack[NFT_JUMP_STACK_SIZE];
+	struct nft_stats *stats;
+	int rulenum;
+	unsigned int gencursor = nft_genmask_cur(net);
+
+do_chain:
+	rulenum = 0;
+	rule = list_entry(&chain->rules, struct nft_rule, list);
+next_rule:
+	regs.verdict.code = NFT_CONTINUE;
+	list_for_each_entry_continue_rcu(rule, &chain->rules, list) {
+
+		/* This rule is not active, skip. */
+		if (unlikely(rule->genmask & (1 << gencursor)))
+			continue;
+
+		rulenum++;
+
+		nft_rule_for_each_expr(expr, last, rule) {
+			if (expr->ops == &nft_cmp_fast_ops)
+				nft_cmp_fast_eval(expr, &regs);
+			else if (expr->ops != &nft_payload_fast_ops ||
+				 !nft_payload_fast_eval(expr, &regs, pkt))
+				expr->ops->eval(expr, &regs, pkt);
+
+			if (regs.verdict.code != NFT_CONTINUE)
+				break;
+		}
+
+		switch (regs.verdict.code) {
+		case NFT_BREAK:
+			regs.verdict.code = NFT_CONTINUE;
+			continue;
+		case NFT_CONTINUE:
+			nft_trace_packet(pkt, chain, rulenum, NFT_TRACE_RULE);
+			continue;
+		}
+		break;
+	}
+
+	switch (regs.verdict.code & NF_VERDICT_MASK) {
+	case NF_ACCEPT:
+	case NF_DROP:
+	case NF_QUEUE:
+		nft_trace_packet(pkt, chain, rulenum, NFT_TRACE_RULE);
+		return regs.verdict.code;
+	}
+
+	switch (regs.verdict.code) {
+	case NFT_JUMP:
+		BUG_ON(stackptr >= NFT_JUMP_STACK_SIZE);
+		jumpstack[stackptr].chain = chain;
+		jumpstack[stackptr].rule  = rule;
+		jumpstack[stackptr].rulenum = rulenum;
+		stackptr++;
+		/* fall through */
+	case NFT_GOTO:
+		nft_trace_packet(pkt, chain, rulenum, NFT_TRACE_RULE);
+
+		chain = regs.verdict.chain;
+		goto do_chain;
+	case NFT_CONTINUE:
+		rulenum++;
+		/* fall through */
+	case NFT_RETURN:
+		nft_trace_packet(pkt, chain, rulenum, NFT_TRACE_RETURN);
+		break;
+	default:
+		WARN_ON(1);
+	}
+
+	if (stackptr > 0) {
+		stackptr--;
+		chain = jumpstack[stackptr].chain;
+		rule  = jumpstack[stackptr].rule;
+		rulenum = jumpstack[stackptr].rulenum;
+		goto next_rule;
+	}
+
+	nft_trace_packet(pkt, basechain, -1, NFT_TRACE_POLICY);
+
+	rcu_read_lock_bh();
+	stats = this_cpu_ptr(rcu_dereference(nft_base_chain(basechain)->stats));
+	u64_stats_update_begin(&stats->syncp);
+	stats->pkts++;
+	stats->bytes += pkt->skb->len;
+	u64_stats_update_end(&stats->syncp);
+	rcu_read_unlock_bh();
+
+	return nft_base_chain(basechain)->policy;
+}
+EXPORT_SYMBOL_GPL(nft_do_chain);
+
+int __init nf_tables_core_module_init(void)
+{
+	int err;
+
+	err = nft_immediate_module_init();
+	if (err < 0)
+		goto err1;
+
+	err = nft_cmp_module_init();
+	if (err < 0)
+		goto err2;
+
+	err = nft_lookup_module_init();
+	if (err < 0)
+		goto err3;
+
+	err = nft_bitwise_module_init();
+	if (err < 0)
+		goto err4;
+
+	err = nft_byteorder_module_init();
+	if (err < 0)
+		goto err5;
+
+	err = nft_payload_module_init();
+	if (err < 0)
+		goto err6;
+
+	err = nft_dynset_module_init();
+	if (err < 0)
+		goto err7;
+
+	return 0;
+
+err7:
+	nft_payload_module_exit();
+err6:
+	nft_byteorder_module_exit();
+err5:
+	nft_bitwise_module_exit();
+err4:
+	nft_lookup_module_exit();
+err3:
+	nft_cmp_module_exit();
+err2:
+	nft_immediate_module_exit();
+err1:
+	return err;
+}
+
+void nf_tables_core_module_exit(void)
+{
+	nft_dynset_module_exit();
+	nft_payload_module_exit();
+	nft_byteorder_module_exit();
+	nft_bitwise_module_exit();
+	nft_lookup_module_exit();
+	nft_cmp_module_exit();
+	nft_immediate_module_exit();
+}