Blame view
net/netfilter/nf_tables_core.c
6.74 KB
81f7e3824
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 |
/* * 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_base_chain *base_chain; struct nft_stats *stats; base_chain = nft_base_chain(chain); if (!base_chain->stats) return; local_bh_disable(); stats = this_cpu_ptr(rcu_dereference(base_chain->stats)); if (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: if (WARN_ON_ONCE(stackptr >= NFT_JUMP_STACK_SIZE)) return NF_DROP; 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]); } |