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);
30 mask = ~0U >> (sizeof(priv->data) * BITS_PER_BYTE - priv->len);
31 if ((data[priv->sreg].data[0] & mask) == priv->data)
33 data[NFT_REG_VERDICT].verdict = NFT_BREAK;
36 static bool nft_payload_fast_eval(const struct nft_expr *expr,
37 struct nft_data data[NFT_REG_MAX + 1],
38 const struct nft_pktinfo *pkt)
40 const struct nft_payload *priv = nft_expr_priv(expr);
41 const struct sk_buff *skb = pkt->skb;
42 struct nft_data *dest = &data[priv->dreg];
45 if (priv->base == NFT_PAYLOAD_NETWORK_HEADER)
46 ptr = skb_network_header(skb);
48 ptr = skb_network_header(skb) + pkt->xt.thoff;
52 if (unlikely(ptr + priv->len >= skb_tail_pointer(skb)))
56 *(u16 *)dest->data = *(u16 *)ptr;
57 else if (priv->len == 4)
58 *(u32 *)dest->data = *(u32 *)ptr;
60 *(u8 *)dest->data = *(u8 *)ptr;
64 struct nft_jumpstack {
65 const struct nft_chain *chain;
66 const struct nft_rule *rule;
71 nft_chain_stats(const struct nft_chain *this, const struct nft_pktinfo *pkt,
72 struct nft_jumpstack *jumpstack, unsigned int stackptr)
74 struct nft_stats __percpu *stats;
75 const struct nft_chain *chain = stackptr ? jumpstack[0].chain : this;
78 stats = rcu_dereference(nft_base_chain(chain)->stats);
79 __this_cpu_inc(stats->pkts);
80 __this_cpu_add(stats->bytes, pkt->skb->len);
90 static const char *const comments[] = {
91 [NFT_TRACE_RULE] = "rule",
92 [NFT_TRACE_RETURN] = "return",
93 [NFT_TRACE_POLICY] = "policy",
96 static struct nf_loginfo trace_loginfo = {
97 .type = NF_LOG_TYPE_LOG,
101 .logflags = NF_LOG_MASK,
106 static void nft_trace_packet(const struct nft_pktinfo *pkt,
107 const struct nft_chain *chain,
108 int rulenum, enum nft_trace type)
110 struct net *net = dev_net(pkt->in ? pkt->in : pkt->out);
112 nf_log_packet(net, pkt->xt.family, pkt->ops->hooknum, pkt->skb, pkt->in,
113 pkt->out, &trace_loginfo, "TRACE: %s:%s:%s:%u ",
114 chain->table->name, chain->name, comments[type],
119 nft_do_chain(struct nft_pktinfo *pkt, const struct nf_hook_ops *ops)
121 const struct nft_chain *chain = ops->priv;
122 const struct nft_rule *rule;
123 const struct nft_expr *expr, *last;
124 struct nft_data data[NFT_REG_MAX + 1];
125 unsigned int stackptr = 0;
126 struct nft_jumpstack jumpstack[NFT_JUMP_STACK_SIZE];
129 * Cache cursor to avoid problems in case that the cursor is updated
130 * while traversing the ruleset.
132 unsigned int gencursor = ACCESS_ONCE(chain->net->nft.gencursor);
135 rule = list_entry(&chain->rules, struct nft_rule, list);
137 data[NFT_REG_VERDICT].verdict = NFT_CONTINUE;
138 list_for_each_entry_continue_rcu(rule, &chain->rules, list) {
140 /* This rule is not active, skip. */
141 if (unlikely(rule->genmask & (1 << gencursor)))
146 nft_rule_for_each_expr(expr, last, rule) {
147 if (expr->ops == &nft_cmp_fast_ops)
148 nft_cmp_fast_eval(expr, data);
149 else if (expr->ops != &nft_payload_fast_ops ||
150 !nft_payload_fast_eval(expr, data, pkt))
151 expr->ops->eval(expr, data, pkt);
153 if (data[NFT_REG_VERDICT].verdict != NFT_CONTINUE)
157 switch (data[NFT_REG_VERDICT].verdict) {
159 data[NFT_REG_VERDICT].verdict = NFT_CONTINUE;
167 switch (data[NFT_REG_VERDICT].verdict & NF_VERDICT_MASK) {
171 if (unlikely(pkt->skb->nf_trace))
172 nft_trace_packet(pkt, chain, rulenum, NFT_TRACE_RULE);
174 return data[NFT_REG_VERDICT].verdict;
177 switch (data[NFT_REG_VERDICT].verdict) {
179 if (unlikely(pkt->skb->nf_trace))
180 nft_trace_packet(pkt, chain, rulenum, NFT_TRACE_RULE);
182 BUG_ON(stackptr >= NFT_JUMP_STACK_SIZE);
183 jumpstack[stackptr].chain = chain;
184 jumpstack[stackptr].rule = rule;
185 jumpstack[stackptr].rulenum = rulenum;
189 chain = data[NFT_REG_VERDICT].chain;
192 if (unlikely(pkt->skb->nf_trace))
193 nft_trace_packet(pkt, chain, rulenum, NFT_TRACE_RETURN);
203 if (unlikely(pkt->skb->nf_trace))
204 nft_trace_packet(pkt, chain, ++rulenum, NFT_TRACE_RETURN);
207 chain = jumpstack[stackptr].chain;
208 rule = jumpstack[stackptr].rule;
209 rulenum = jumpstack[stackptr].rulenum;
212 nft_chain_stats(chain, pkt, jumpstack, stackptr);
214 if (unlikely(pkt->skb->nf_trace))
215 nft_trace_packet(pkt, chain, ++rulenum, NFT_TRACE_POLICY);
217 return nft_base_chain(chain)->policy;
219 EXPORT_SYMBOL_GPL(nft_do_chain);
221 int __init nf_tables_core_module_init(void)
225 err = nft_immediate_module_init();
229 err = nft_cmp_module_init();
233 err = nft_lookup_module_init();
237 err = nft_bitwise_module_init();
241 err = nft_byteorder_module_init();
245 err = nft_payload_module_init();
252 nft_byteorder_module_exit();
254 nft_bitwise_module_exit();
256 nft_lookup_module_exit();
258 nft_cmp_module_exit();
260 nft_immediate_module_exit();
265 void nf_tables_core_module_exit(void)
267 nft_payload_module_exit();
268 nft_byteorder_module_exit();
269 nft_bitwise_module_exit();
270 nft_lookup_module_exit();
271 nft_cmp_module_exit();
272 nft_immediate_module_exit();