2 * Copyright (c) 2008 Patrick McHardy <kaber@trash.net>
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
8 * Development of this code funded by Astaro AG (http://www.astaro.com/)
11 #include <linux/module.h>
12 #include <linux/init.h>
13 #include <linux/list.h>
14 #include <linux/rculist.h>
15 #include <linux/skbuff.h>
16 #include <linux/netlink.h>
17 #include <linux/netfilter.h>
18 #include <linux/netfilter/nfnetlink.h>
19 #include <linux/netfilter/nf_tables.h>
20 #include <net/netfilter/nf_tables_core.h>
21 #include <net/netfilter/nf_tables.h>
22 #include <net/netfilter/nf_log.h>
24 static void nft_cmp_fast_eval(const struct nft_expr *expr,
25 struct nft_data data[NFT_REG_MAX + 1])
27 const struct nft_cmp_fast_expr *priv = nft_expr_priv(expr);
28 u32 mask = nft_cmp_fast_mask(priv->len);
30 if ((data[priv->sreg].data[0] & mask) == priv->data)
32 data[NFT_REG_VERDICT].verdict = NFT_BREAK;
35 static bool nft_payload_fast_eval(const struct nft_expr *expr,
36 struct nft_data data[NFT_REG_MAX + 1],
37 const struct nft_pktinfo *pkt)
39 const struct nft_payload *priv = nft_expr_priv(expr);
40 const struct sk_buff *skb = pkt->skb;
41 struct nft_data *dest = &data[priv->dreg];
44 if (priv->base == NFT_PAYLOAD_NETWORK_HEADER)
45 ptr = skb_network_header(skb);
47 ptr = skb_network_header(skb) + pkt->xt.thoff;
51 if (unlikely(ptr + priv->len >= skb_tail_pointer(skb)))
55 *(u16 *)dest->data = *(u16 *)ptr;
56 else if (priv->len == 4)
57 *(u32 *)dest->data = *(u32 *)ptr;
59 *(u8 *)dest->data = *(u8 *)ptr;
63 struct nft_jumpstack {
64 const struct nft_chain *chain;
65 const struct nft_rule *rule;
70 nft_chain_stats(const struct nft_chain *this, const struct nft_pktinfo *pkt,
71 struct nft_jumpstack *jumpstack, unsigned int stackptr)
73 struct nft_stats __percpu *stats;
74 const struct nft_chain *chain = stackptr ? jumpstack[0].chain : this;
77 stats = rcu_dereference(nft_base_chain(chain)->stats);
78 __this_cpu_inc(stats->pkts);
79 __this_cpu_add(stats->bytes, pkt->skb->len);
89 static const char *const comments[] = {
90 [NFT_TRACE_RULE] = "rule",
91 [NFT_TRACE_RETURN] = "return",
92 [NFT_TRACE_POLICY] = "policy",
95 static struct nf_loginfo trace_loginfo = {
96 .type = NF_LOG_TYPE_LOG,
100 .logflags = NF_LOG_MASK,
105 static void nft_trace_packet(const struct nft_pktinfo *pkt,
106 const struct nft_chain *chain,
107 int rulenum, enum nft_trace type)
109 struct net *net = dev_net(pkt->in ? pkt->in : pkt->out);
111 nf_log_packet(net, pkt->xt.family, pkt->ops->hooknum, pkt->skb, pkt->in,
112 pkt->out, &trace_loginfo, "TRACE: %s:%s:%s:%u ",
113 chain->table->name, chain->name, comments[type],
118 nft_do_chain(struct nft_pktinfo *pkt, const struct nf_hook_ops *ops)
120 const struct nft_chain *chain = ops->priv;
121 const struct nft_rule *rule;
122 const struct nft_expr *expr, *last;
123 struct nft_data data[NFT_REG_MAX + 1];
124 unsigned int stackptr = 0;
125 struct nft_jumpstack jumpstack[NFT_JUMP_STACK_SIZE];
128 * Cache cursor to avoid problems in case that the cursor is updated
129 * while traversing the ruleset.
131 unsigned int gencursor = ACCESS_ONCE(chain->net->nft.gencursor);
134 rule = list_entry(&chain->rules, struct nft_rule, list);
136 data[NFT_REG_VERDICT].verdict = NFT_CONTINUE;
137 list_for_each_entry_continue_rcu(rule, &chain->rules, list) {
139 /* This rule is not active, skip. */
140 if (unlikely(rule->genmask & (1 << gencursor)))
145 nft_rule_for_each_expr(expr, last, rule) {
146 if (expr->ops == &nft_cmp_fast_ops)
147 nft_cmp_fast_eval(expr, data);
148 else if (expr->ops != &nft_payload_fast_ops ||
149 !nft_payload_fast_eval(expr, data, pkt))
150 expr->ops->eval(expr, data, pkt);
152 if (data[NFT_REG_VERDICT].verdict != NFT_CONTINUE)
156 switch (data[NFT_REG_VERDICT].verdict) {
158 data[NFT_REG_VERDICT].verdict = NFT_CONTINUE;
166 switch (data[NFT_REG_VERDICT].verdict & NF_VERDICT_MASK) {
170 if (unlikely(pkt->skb->nf_trace))
171 nft_trace_packet(pkt, chain, rulenum, NFT_TRACE_RULE);
173 return data[NFT_REG_VERDICT].verdict;
176 switch (data[NFT_REG_VERDICT].verdict) {
178 if (unlikely(pkt->skb->nf_trace))
179 nft_trace_packet(pkt, chain, rulenum, NFT_TRACE_RULE);
181 BUG_ON(stackptr >= NFT_JUMP_STACK_SIZE);
182 jumpstack[stackptr].chain = chain;
183 jumpstack[stackptr].rule = rule;
184 jumpstack[stackptr].rulenum = rulenum;
188 chain = data[NFT_REG_VERDICT].chain;
191 if (unlikely(pkt->skb->nf_trace))
192 nft_trace_packet(pkt, chain, rulenum, NFT_TRACE_RETURN);
202 if (unlikely(pkt->skb->nf_trace))
203 nft_trace_packet(pkt, chain, ++rulenum, NFT_TRACE_RETURN);
206 chain = jumpstack[stackptr].chain;
207 rule = jumpstack[stackptr].rule;
208 rulenum = jumpstack[stackptr].rulenum;
211 nft_chain_stats(chain, pkt, jumpstack, stackptr);
213 if (unlikely(pkt->skb->nf_trace))
214 nft_trace_packet(pkt, chain, ++rulenum, NFT_TRACE_POLICY);
216 return nft_base_chain(chain)->policy;
218 EXPORT_SYMBOL_GPL(nft_do_chain);
220 int __init nf_tables_core_module_init(void)
224 err = nft_immediate_module_init();
228 err = nft_cmp_module_init();
232 err = nft_lookup_module_init();
236 err = nft_bitwise_module_init();
240 err = nft_byteorder_module_init();
244 err = nft_payload_module_init();
251 nft_byteorder_module_exit();
253 nft_bitwise_module_exit();
255 nft_lookup_module_exit();
257 nft_cmp_module_exit();
259 nft_immediate_module_exit();
264 void nf_tables_core_module_exit(void)
266 nft_payload_module_exit();
267 nft_byteorder_module_exit();
268 nft_bitwise_module_exit();
269 nft_lookup_module_exit();
270 nft_cmp_module_exit();
271 nft_immediate_module_exit();