1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2009 Patrick McHardy <kaber@trash.net> 4 * 5 * Development of this code funded by Astaro AG (http://www.astaro.com/) 6 */ 7 8 #include <linux/kernel.h> 9 #include <linux/init.h> 10 #include <linux/list.h> 11 #include <linux/rbtree.h> 12 #include <linux/netlink.h> 13 #include <linux/netfilter.h> 14 #include <linux/netfilter/nf_tables.h> 15 #include <net/netfilter/nf_tables.h> 16 #include <net/netfilter/nf_tables_core.h> 17 18 struct nft_lookup { 19 struct nft_set *set; 20 u8 sreg; 21 u8 dreg; 22 bool invert; 23 struct nft_set_binding binding; 24 }; 25 26 #ifdef CONFIG_RETPOLINE 27 bool nft_set_do_lookup(const struct net *net, const struct nft_set *set, 28 const u32 *key, const struct nft_set_ext **ext) 29 { 30 if (set->ops == &nft_set_hash_fast_type.ops) 31 return nft_hash_lookup_fast(net, set, key, ext); 32 if (set->ops == &nft_set_hash_type.ops) 33 return nft_hash_lookup(net, set, key, ext); 34 35 if (set->ops == &nft_set_rhash_type.ops) 36 return nft_rhash_lookup(net, set, key, ext); 37 38 if (set->ops == &nft_set_bitmap_type.ops) 39 return nft_bitmap_lookup(net, set, key, ext); 40 41 if (set->ops == &nft_set_pipapo_type.ops) 42 return nft_pipapo_lookup(net, set, key, ext); 43 #if defined(CONFIG_X86_64) && !defined(CONFIG_UML) 44 if (set->ops == &nft_set_pipapo_avx2_type.ops) 45 return nft_pipapo_avx2_lookup(net, set, key, ext); 46 #endif 47 48 if (set->ops == &nft_set_rbtree_type.ops) 49 return nft_rbtree_lookup(net, set, key, ext); 50 51 WARN_ON_ONCE(1); 52 return set->ops->lookup(net, set, key, ext); 53 } 54 EXPORT_SYMBOL_GPL(nft_set_do_lookup); 55 #endif 56 57 void nft_lookup_eval(const struct nft_expr *expr, 58 struct nft_regs *regs, 59 const struct nft_pktinfo *pkt) 60 { 61 const struct nft_lookup *priv = nft_expr_priv(expr); 62 const struct nft_set *set = priv->set; 63 const struct nft_set_ext *ext = NULL; 64 const struct net *net = nft_net(pkt); 65 bool found; 66 67 found = nft_set_do_lookup(net, set, ®s->data[priv->sreg], &ext) ^ 68 priv->invert; 69 if (!found) { 70 ext = nft_set_catchall_lookup(net, set); 71 if (!ext) { 72 regs->verdict.code = NFT_BREAK; 73 return; 74 } 75 } 76 77 if (ext) { 78 if (set->flags & NFT_SET_MAP) 79 nft_data_copy(®s->data[priv->dreg], 80 nft_set_ext_data(ext), set->dlen); 81 82 nft_set_elem_update_expr(ext, regs, pkt); 83 } 84 } 85 86 static const struct nla_policy nft_lookup_policy[NFTA_LOOKUP_MAX + 1] = { 87 [NFTA_LOOKUP_SET] = { .type = NLA_STRING, 88 .len = NFT_SET_MAXNAMELEN - 1 }, 89 [NFTA_LOOKUP_SET_ID] = { .type = NLA_U32 }, 90 [NFTA_LOOKUP_SREG] = { .type = NLA_U32 }, 91 [NFTA_LOOKUP_DREG] = { .type = NLA_U32 }, 92 [NFTA_LOOKUP_FLAGS] = { .type = NLA_U32 }, 93 }; 94 95 static int nft_lookup_init(const struct nft_ctx *ctx, 96 const struct nft_expr *expr, 97 const struct nlattr * const tb[]) 98 { 99 struct nft_lookup *priv = nft_expr_priv(expr); 100 u8 genmask = nft_genmask_next(ctx->net); 101 struct nft_set *set; 102 u32 flags; 103 int err; 104 105 if (tb[NFTA_LOOKUP_SET] == NULL || 106 tb[NFTA_LOOKUP_SREG] == NULL) 107 return -EINVAL; 108 109 set = nft_set_lookup_global(ctx->net, ctx->table, tb[NFTA_LOOKUP_SET], 110 tb[NFTA_LOOKUP_SET_ID], genmask); 111 if (IS_ERR(set)) 112 return PTR_ERR(set); 113 114 err = nft_parse_register_load(tb[NFTA_LOOKUP_SREG], &priv->sreg, 115 set->klen); 116 if (err < 0) 117 return err; 118 119 if (tb[NFTA_LOOKUP_FLAGS]) { 120 flags = ntohl(nla_get_be32(tb[NFTA_LOOKUP_FLAGS])); 121 122 if (flags & ~NFT_LOOKUP_F_INV) 123 return -EINVAL; 124 125 if (flags & NFT_LOOKUP_F_INV) { 126 if (set->flags & NFT_SET_MAP) 127 return -EINVAL; 128 priv->invert = true; 129 } 130 } 131 132 if (tb[NFTA_LOOKUP_DREG] != NULL) { 133 if (priv->invert) 134 return -EINVAL; 135 if (!(set->flags & NFT_SET_MAP)) 136 return -EINVAL; 137 138 err = nft_parse_register_store(ctx, tb[NFTA_LOOKUP_DREG], 139 &priv->dreg, NULL, set->dtype, 140 set->dlen); 141 if (err < 0) 142 return err; 143 } else if (set->flags & NFT_SET_MAP) 144 return -EINVAL; 145 146 priv->binding.flags = set->flags & NFT_SET_MAP; 147 148 err = nf_tables_bind_set(ctx, set, &priv->binding); 149 if (err < 0) 150 return err; 151 152 priv->set = set; 153 return 0; 154 } 155 156 static void nft_lookup_deactivate(const struct nft_ctx *ctx, 157 const struct nft_expr *expr, 158 enum nft_trans_phase phase) 159 { 160 struct nft_lookup *priv = nft_expr_priv(expr); 161 162 nf_tables_deactivate_set(ctx, priv->set, &priv->binding, phase); 163 } 164 165 static void nft_lookup_activate(const struct nft_ctx *ctx, 166 const struct nft_expr *expr) 167 { 168 struct nft_lookup *priv = nft_expr_priv(expr); 169 170 priv->set->use++; 171 } 172 173 static void nft_lookup_destroy(const struct nft_ctx *ctx, 174 const struct nft_expr *expr) 175 { 176 struct nft_lookup *priv = nft_expr_priv(expr); 177 178 nf_tables_destroy_set(ctx, priv->set); 179 } 180 181 static int nft_lookup_dump(struct sk_buff *skb, const struct nft_expr *expr) 182 { 183 const struct nft_lookup *priv = nft_expr_priv(expr); 184 u32 flags = priv->invert ? NFT_LOOKUP_F_INV : 0; 185 186 if (nla_put_string(skb, NFTA_LOOKUP_SET, priv->set->name)) 187 goto nla_put_failure; 188 if (nft_dump_register(skb, NFTA_LOOKUP_SREG, priv->sreg)) 189 goto nla_put_failure; 190 if (priv->set->flags & NFT_SET_MAP) 191 if (nft_dump_register(skb, NFTA_LOOKUP_DREG, priv->dreg)) 192 goto nla_put_failure; 193 if (nla_put_be32(skb, NFTA_LOOKUP_FLAGS, htonl(flags))) 194 goto nla_put_failure; 195 return 0; 196 197 nla_put_failure: 198 return -1; 199 } 200 201 static int nft_lookup_validate_setelem(const struct nft_ctx *ctx, 202 struct nft_set *set, 203 const struct nft_set_iter *iter, 204 struct nft_set_elem *elem) 205 { 206 const struct nft_set_ext *ext = nft_set_elem_ext(set, elem->priv); 207 struct nft_ctx *pctx = (struct nft_ctx *)ctx; 208 const struct nft_data *data; 209 int err; 210 211 if (nft_set_ext_exists(ext, NFT_SET_EXT_FLAGS) && 212 *nft_set_ext_flags(ext) & NFT_SET_ELEM_INTERVAL_END) 213 return 0; 214 215 data = nft_set_ext_data(ext); 216 switch (data->verdict.code) { 217 case NFT_JUMP: 218 case NFT_GOTO: 219 pctx->level++; 220 err = nft_chain_validate(ctx, data->verdict.chain); 221 if (err < 0) 222 return err; 223 pctx->level--; 224 break; 225 default: 226 break; 227 } 228 229 return 0; 230 } 231 232 static int nft_lookup_validate(const struct nft_ctx *ctx, 233 const struct nft_expr *expr, 234 const struct nft_data **d) 235 { 236 const struct nft_lookup *priv = nft_expr_priv(expr); 237 struct nft_set_iter iter; 238 239 if (!(priv->set->flags & NFT_SET_MAP) || 240 priv->set->dtype != NFT_DATA_VERDICT) 241 return 0; 242 243 iter.genmask = nft_genmask_next(ctx->net); 244 iter.skip = 0; 245 iter.count = 0; 246 iter.err = 0; 247 iter.fn = nft_lookup_validate_setelem; 248 249 priv->set->ops->walk(ctx, priv->set, &iter); 250 if (iter.err < 0) 251 return iter.err; 252 253 return 0; 254 } 255 256 static bool nft_lookup_reduce(struct nft_regs_track *track, 257 const struct nft_expr *expr) 258 { 259 const struct nft_lookup *priv = nft_expr_priv(expr); 260 261 if (priv->set->flags & NFT_SET_MAP) 262 nft_reg_track_cancel(track, priv->dreg, priv->set->dlen); 263 264 return false; 265 } 266 267 static const struct nft_expr_ops nft_lookup_ops = { 268 .type = &nft_lookup_type, 269 .size = NFT_EXPR_SIZE(sizeof(struct nft_lookup)), 270 .eval = nft_lookup_eval, 271 .init = nft_lookup_init, 272 .activate = nft_lookup_activate, 273 .deactivate = nft_lookup_deactivate, 274 .destroy = nft_lookup_destroy, 275 .dump = nft_lookup_dump, 276 .validate = nft_lookup_validate, 277 .reduce = nft_lookup_reduce, 278 }; 279 280 struct nft_expr_type nft_lookup_type __read_mostly = { 281 .name = "lookup", 282 .ops = &nft_lookup_ops, 283 .policy = nft_lookup_policy, 284 .maxattr = NFTA_LOOKUP_MAX, 285 .owner = THIS_MODULE, 286 }; 287