| /* |
| * 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/static_key.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> |
| |
| static const char *const comments[__NFT_TRACETYPE_MAX] = { |
| [NFT_TRACETYPE_POLICY] = "policy", |
| [NFT_TRACETYPE_RETURN] = "return", |
| [NFT_TRACETYPE_RULE] = "rule", |
| }; |
| |
| static const struct nf_loginfo trace_loginfo = { |
| .type = NF_LOG_TYPE_LOG, |
| .u = { |
| .log = { |
| .level = LOGLEVEL_WARNING, |
| .logflags = NF_LOG_DEFAULT_MASK, |
| }, |
| }, |
| }; |
| |
| static noinline void __nft_trace_packet(struct nft_traceinfo *info, |
| const struct nft_chain *chain, |
| int rulenum, enum nft_trace_types type) |
| { |
| const struct nft_pktinfo *pkt = info->pkt; |
| |
| if (!info->trace || !pkt->skb->nf_trace) |
| return; |
| |
| info->chain = chain; |
| info->type = type; |
| |
| nft_trace_notify(info); |
| |
| nf_log_trace(nft_net(pkt), nft_pf(pkt), nft_hook(pkt), pkt->skb, |
| nft_in(pkt), nft_out(pkt), &trace_loginfo, |
| "TRACE: %s:%s:%s:%u ", |
| chain->table->name, chain->name, comments[type], rulenum); |
| } |
| |
| static inline void nft_trace_packet(struct nft_traceinfo *info, |
| const struct nft_chain *chain, |
| const struct nft_rule *rule, |
| int rulenum, |
| enum nft_trace_types type) |
| { |
| if (static_branch_unlikely(&nft_trace_enabled)) { |
| info->rule = rule; |
| __nft_trace_packet(info, 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 = ®s->data[priv->dreg]; |
| unsigned char *ptr; |
| |
| if (priv->base == NFT_PAYLOAD_NETWORK_HEADER) |
| ptr = skb_network_header(skb); |
| else { |
| if (!pkt->tprot_set) |
| return false; |
| 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; |
| } |
| |
| DEFINE_STATIC_KEY_FALSE(nft_counters_enabled); |
| |
| static noinline void nft_update_chain_stats(const struct nft_chain *chain, |
| const struct nft_pktinfo *pkt) |
| { |
| struct nft_stats *stats; |
| |
| local_bh_disable(); |
| stats = this_cpu_ptr(rcu_dereference(nft_base_chain(chain)->stats)); |
| u64_stats_update_begin(&stats->syncp); |
| stats->pkts++; |
| stats->bytes += pkt->skb->len; |
| u64_stats_update_end(&stats->syncp); |
| local_bh_enable(); |
| } |
| |
| struct nft_jumpstack { |
| const struct nft_chain *chain; |
| const struct nft_rule *rule; |
| int rulenum; |
| }; |
| |
| unsigned int |
| nft_do_chain(struct nft_pktinfo *pkt, void *priv) |
| { |
| const struct nft_chain *chain = priv, *basechain = chain; |
| const struct net *net = nft_net(pkt); |
| 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]; |
| int rulenum; |
| unsigned int gencursor = nft_genmask_cur(net); |
| struct nft_traceinfo info; |
| |
| info.trace = false; |
| if (static_branch_unlikely(&nft_trace_enabled)) |
| nft_trace_init(&info, pkt, ®s.verdict, basechain); |
| 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 & gencursor)) |
| continue; |
| |
| rulenum++; |
| |
| nft_rule_for_each_expr(expr, last, rule) { |
| if (expr->ops == &nft_cmp_fast_ops) |
| nft_cmp_fast_eval(expr, ®s); |
| else if (expr->ops != &nft_payload_fast_ops || |
| !nft_payload_fast_eval(expr, ®s, pkt)) |
| expr->ops->eval(expr, ®s, 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(&info, chain, rule, |
| rulenum, NFT_TRACETYPE_RULE); |
| continue; |
| } |
| break; |
| } |
| |
| switch (regs.verdict.code & NF_VERDICT_MASK) { |
| case NF_ACCEPT: |
| case NF_DROP: |
| case NF_QUEUE: |
| case NF_STOLEN: |
| nft_trace_packet(&info, chain, rule, |
| rulenum, NFT_TRACETYPE_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(&info, chain, rule, |
| rulenum, NFT_TRACETYPE_RULE); |
| |
| chain = regs.verdict.chain; |
| goto do_chain; |
| case NFT_CONTINUE: |
| rulenum++; |
| /* fall through */ |
| case NFT_RETURN: |
| nft_trace_packet(&info, chain, rule, |
| rulenum, NFT_TRACETYPE_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(&info, basechain, NULL, -1, |
| NFT_TRACETYPE_POLICY); |
| |
| if (static_branch_unlikely(&nft_counters_enabled)) |
| nft_update_chain_stats(basechain, pkt); |
| |
| return nft_base_chain(basechain)->policy; |
| } |
| EXPORT_SYMBOL_GPL(nft_do_chain); |
| |
| static struct nft_expr_type *nft_basic_types[] = { |
| &nft_imm_type, |
| &nft_cmp_type, |
| &nft_lookup_type, |
| &nft_bitwise_type, |
| &nft_byteorder_type, |
| &nft_payload_type, |
| &nft_dynset_type, |
| &nft_range_type, |
| }; |
| |
| int __init nf_tables_core_module_init(void) |
| { |
| int err, i; |
| |
| for (i = 0; i < ARRAY_SIZE(nft_basic_types); i++) { |
| err = nft_register_expr(nft_basic_types[i]); |
| if (err) |
| goto err; |
| } |
| |
| return 0; |
| |
| err: |
| while (i-- > 0) |
| nft_unregister_expr(nft_basic_types[i]); |
| return err; |
| } |
| |
| void nf_tables_core_module_exit(void) |
| { |
| int i; |
| |
| i = ARRAY_SIZE(nft_basic_types); |
| while (i-- > 0) |
| nft_unregister_expr(nft_basic_types[i]); |
| } |