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/kernel.h>
12 #include <linux/module.h>
13 #include <linux/init.h>
14 #include <linux/list.h>
15 #include <linux/rculist.h>
16 #include <linux/skbuff.h>
17 #include <linux/netlink.h>
18 #include <linux/netfilter.h>
19 #include <linux/static_key.h>
20 #include <linux/netfilter/nfnetlink.h>
21 #include <linux/netfilter/nf_tables.h>
22 #include <net/netfilter/nf_tables_core.h>
23 #include <net/netfilter/nf_tables.h>
24 #include <net/netfilter/nf_log.h>
26 static const char *const comments[__NFT_TRACETYPE_MAX] = {
27 [NFT_TRACETYPE_POLICY] = "policy",
28 [NFT_TRACETYPE_RETURN] = "return",
29 [NFT_TRACETYPE_RULE] = "rule",
32 static const struct nf_loginfo trace_loginfo = {
33 .type = NF_LOG_TYPE_LOG,
36 .level = LOGLEVEL_WARNING,
37 .logflags = NF_LOG_DEFAULT_MASK,
42 static noinline void __nft_trace_packet(struct nft_traceinfo *info,
43 const struct nft_chain *chain,
44 int rulenum, enum nft_trace_types type)
46 const struct nft_pktinfo *pkt = info->pkt;
48 if (!info->trace || !pkt->skb->nf_trace)
54 nft_trace_notify(info);
56 nf_log_trace(nft_net(pkt), nft_pf(pkt), nft_hook(pkt), pkt->skb,
57 nft_in(pkt), nft_out(pkt), &trace_loginfo,
58 "TRACE: %s:%s:%s:%u ",
59 chain->table->name, chain->name, comments[type], rulenum);
62 static inline void nft_trace_packet(struct nft_traceinfo *info,
63 const struct nft_chain *chain,
64 const struct nft_rule *rule,
66 enum nft_trace_types type)
68 if (static_branch_unlikely(&nft_trace_enabled)) {
70 __nft_trace_packet(info, chain, rulenum, type);
74 static void nft_cmp_fast_eval(const struct nft_expr *expr,
75 struct nft_regs *regs)
77 const struct nft_cmp_fast_expr *priv = nft_expr_priv(expr);
78 u32 mask = nft_cmp_fast_mask(priv->len);
80 if ((regs->data[priv->sreg] & mask) == priv->data)
82 regs->verdict.code = NFT_BREAK;
85 static bool nft_payload_fast_eval(const struct nft_expr *expr,
86 struct nft_regs *regs,
87 const struct nft_pktinfo *pkt)
89 const struct nft_payload *priv = nft_expr_priv(expr);
90 const struct sk_buff *skb = pkt->skb;
91 u32 *dest = ®s->data[priv->dreg];
94 if (priv->base == NFT_PAYLOAD_NETWORK_HEADER)
95 ptr = skb_network_header(skb);
99 ptr = skb_network_header(skb) + pkt->xt.thoff;
104 if (unlikely(ptr + priv->len > skb_tail_pointer(skb)))
109 *(u16 *)dest = *(u16 *)ptr;
110 else if (priv->len == 4)
111 *(u32 *)dest = *(u32 *)ptr;
113 *(u8 *)dest = *(u8 *)ptr;
117 DEFINE_STATIC_KEY_FALSE(nft_counters_enabled);
119 static noinline void nft_update_chain_stats(const struct nft_chain *chain,
120 const struct nft_pktinfo *pkt)
122 struct nft_base_chain *base_chain;
123 struct nft_stats *stats;
125 base_chain = nft_base_chain(chain);
126 if (!base_chain->stats)
130 stats = this_cpu_ptr(rcu_dereference(base_chain->stats));
132 u64_stats_update_begin(&stats->syncp);
134 stats->bytes += pkt->skb->len;
135 u64_stats_update_end(&stats->syncp);
140 struct nft_jumpstack {
141 const struct nft_chain *chain;
142 const struct nft_rule *rule;
147 nft_do_chain(struct nft_pktinfo *pkt, void *priv)
149 const struct nft_chain *chain = priv, *basechain = chain;
150 const struct net *net = nft_net(pkt);
151 const struct nft_rule *rule;
152 const struct nft_expr *expr, *last;
153 struct nft_regs regs = {};
154 unsigned int stackptr = 0;
155 struct nft_jumpstack jumpstack[NFT_JUMP_STACK_SIZE];
157 unsigned int gencursor = nft_genmask_cur(net);
158 struct nft_traceinfo info;
161 if (static_branch_unlikely(&nft_trace_enabled))
162 nft_trace_init(&info, pkt, ®s.verdict, basechain);
165 rule = list_entry(&chain->rules, struct nft_rule, list);
167 regs.verdict.code = NFT_CONTINUE;
168 list_for_each_entry_continue_rcu(rule, &chain->rules, list) {
170 /* This rule is not active, skip. */
171 if (unlikely(rule->genmask & gencursor))
176 nft_rule_for_each_expr(expr, last, rule) {
177 if (expr->ops == &nft_cmp_fast_ops)
178 nft_cmp_fast_eval(expr, ®s);
179 else if (expr->ops != &nft_payload_fast_ops ||
180 !nft_payload_fast_eval(expr, ®s, pkt))
181 expr->ops->eval(expr, ®s, pkt);
183 if (regs.verdict.code != NFT_CONTINUE)
187 switch (regs.verdict.code) {
189 regs.verdict.code = NFT_CONTINUE;
192 nft_trace_packet(&info, chain, rule,
193 rulenum, NFT_TRACETYPE_RULE);
199 switch (regs.verdict.code & NF_VERDICT_MASK) {
204 nft_trace_packet(&info, chain, rule,
205 rulenum, NFT_TRACETYPE_RULE);
206 return regs.verdict.code;
209 switch (regs.verdict.code) {
211 if (WARN_ON_ONCE(stackptr >= NFT_JUMP_STACK_SIZE))
213 jumpstack[stackptr].chain = chain;
214 jumpstack[stackptr].rule = rule;
215 jumpstack[stackptr].rulenum = rulenum;
219 nft_trace_packet(&info, chain, rule,
220 rulenum, NFT_TRACETYPE_RULE);
222 chain = regs.verdict.chain;
228 nft_trace_packet(&info, chain, rule,
229 rulenum, NFT_TRACETYPE_RETURN);
237 chain = jumpstack[stackptr].chain;
238 rule = jumpstack[stackptr].rule;
239 rulenum = jumpstack[stackptr].rulenum;
243 nft_trace_packet(&info, basechain, NULL, -1,
244 NFT_TRACETYPE_POLICY);
246 if (static_branch_unlikely(&nft_counters_enabled))
247 nft_update_chain_stats(basechain, pkt);
249 return nft_base_chain(basechain)->policy;
251 EXPORT_SYMBOL_GPL(nft_do_chain);
253 static struct nft_expr_type *nft_basic_types[] = {
264 int __init nf_tables_core_module_init(void)
268 for (i = 0; i < ARRAY_SIZE(nft_basic_types); i++) {
269 err = nft_register_expr(nft_basic_types[i]);
278 nft_unregister_expr(nft_basic_types[i]);
282 void nf_tables_core_module_exit(void)
286 i = ARRAY_SIZE(nft_basic_types);
288 nft_unregister_expr(nft_basic_types[i]);