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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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 | // SPDX-License-Identifier: GPL-2.0-only /* * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net> * * Development of this code funded by Astaro AG (http://www.astaro.com/) */ #include <linux/kernel.h> #include <linux/init.h> #include <linux/module.h> #include <linux/netlink.h> #include <linux/netfilter.h> #include <linux/if_arp.h> #include <linux/netfilter/nf_tables.h> #include <net/netfilter/nf_tables_core.h> #include <net/netfilter/nf_tables_offload.h> #include <net/netfilter/nf_tables.h> struct nft_cmp_expr { struct nft_data data; u8 sreg; u8 len; enum nft_cmp_ops op:8; }; void nft_cmp_eval(const struct nft_expr *expr, struct nft_regs *regs, const struct nft_pktinfo *pkt) { const struct nft_cmp_expr *priv = nft_expr_priv(expr); int d; d = memcmp(®s->data[priv->sreg], &priv->data, priv->len); switch (priv->op) { case NFT_CMP_EQ: if (d != 0) goto mismatch; break; case NFT_CMP_NEQ: if (d == 0) goto mismatch; break; case NFT_CMP_LT: if (d == 0) goto mismatch; fallthrough; case NFT_CMP_LTE: if (d > 0) goto mismatch; break; case NFT_CMP_GT: if (d == 0) goto mismatch; fallthrough; case NFT_CMP_GTE: if (d < 0) goto mismatch; break; } return; mismatch: regs->verdict.code = NFT_BREAK; } static const struct nla_policy nft_cmp_policy[NFTA_CMP_MAX + 1] = { [NFTA_CMP_SREG] = { .type = NLA_U32 }, [NFTA_CMP_OP] = { .type = NLA_U32 }, [NFTA_CMP_DATA] = { .type = NLA_NESTED }, }; static int nft_cmp_init(const struct nft_ctx *ctx, const struct nft_expr *expr, const struct nlattr * const tb[]) { struct nft_cmp_expr *priv = nft_expr_priv(expr); struct nft_data_desc desc = { .type = NFT_DATA_VALUE, .size = sizeof(priv->data), }; int err; err = nft_data_init(NULL, &priv->data, &desc, tb[NFTA_CMP_DATA]); if (err < 0) return err; err = nft_parse_register_load(tb[NFTA_CMP_SREG], &priv->sreg, desc.len); if (err < 0) return err; priv->op = ntohl(nla_get_be32(tb[NFTA_CMP_OP])); priv->len = desc.len; return 0; } static int nft_cmp_dump(struct sk_buff *skb, const struct nft_expr *expr, bool reset) { const struct nft_cmp_expr *priv = nft_expr_priv(expr); if (nft_dump_register(skb, NFTA_CMP_SREG, priv->sreg)) goto nla_put_failure; if (nla_put_be32(skb, NFTA_CMP_OP, htonl(priv->op))) goto nla_put_failure; if (nft_data_dump(skb, NFTA_CMP_DATA, &priv->data, NFT_DATA_VALUE, priv->len) < 0) goto nla_put_failure; return 0; nla_put_failure: return -1; } union nft_cmp_offload_data { u16 val16; u32 val32; u64 val64; }; static void nft_payload_n2h(union nft_cmp_offload_data *data, const u8 *val, u32 len) { switch (len) { case 2: data->val16 = ntohs(*((__be16 *)val)); break; case 4: data->val32 = ntohl(*((__be32 *)val)); break; case 8: data->val64 = be64_to_cpu(*((__be64 *)val)); break; default: WARN_ON_ONCE(1); break; } } static int __nft_cmp_offload(struct nft_offload_ctx *ctx, struct nft_flow_rule *flow, const struct nft_cmp_expr *priv) { struct nft_offload_reg *reg = &ctx->regs[priv->sreg]; union nft_cmp_offload_data _data, _datamask; u8 *mask = (u8 *)&flow->match.mask; u8 *key = (u8 *)&flow->match.key; u8 *data, *datamask; if (priv->op != NFT_CMP_EQ || priv->len > reg->len) return -EOPNOTSUPP; if (reg->flags & NFT_OFFLOAD_F_NETWORK2HOST) { nft_payload_n2h(&_data, (u8 *)&priv->data, reg->len); nft_payload_n2h(&_datamask, (u8 *)®->mask, reg->len); data = (u8 *)&_data; datamask = (u8 *)&_datamask; } else { data = (u8 *)&priv->data; datamask = (u8 *)®->mask; } memcpy(key + reg->offset, data, reg->len); memcpy(mask + reg->offset, datamask, reg->len); flow->match.dissector.used_keys |= BIT(reg->key); flow->match.dissector.offset[reg->key] = reg->base_offset; if (reg->key == FLOW_DISSECTOR_KEY_META && reg->offset == offsetof(struct nft_flow_key, meta.ingress_iftype) && nft_reg_load16(priv->data.data) != ARPHRD_ETHER) return -EOPNOTSUPP; nft_offload_update_dependency(ctx, &priv->data, reg->len); return 0; } static int nft_cmp_offload(struct nft_offload_ctx *ctx, struct nft_flow_rule *flow, const struct nft_expr *expr) { const struct nft_cmp_expr *priv = nft_expr_priv(expr); return __nft_cmp_offload(ctx, flow, priv); } static const struct nft_expr_ops nft_cmp_ops = { .type = &nft_cmp_type, .size = NFT_EXPR_SIZE(sizeof(struct nft_cmp_expr)), .eval = nft_cmp_eval, .init = nft_cmp_init, .dump = nft_cmp_dump, .reduce = NFT_REDUCE_READONLY, .offload = nft_cmp_offload, }; /* Calculate the mask for the nft_cmp_fast expression. On big endian the * mask needs to include the *upper* bytes when interpreting that data as * something smaller than the full u32, therefore a cpu_to_le32 is done. */ static u32 nft_cmp_fast_mask(unsigned int len) { __le32 mask = cpu_to_le32(~0U >> (sizeof_field(struct nft_cmp_fast_expr, data) * BITS_PER_BYTE - len)); return (__force u32)mask; } static int nft_cmp_fast_init(const struct nft_ctx *ctx, const struct nft_expr *expr, const struct nlattr * const tb[]) { struct nft_cmp_fast_expr *priv = nft_expr_priv(expr); struct nft_data data; struct nft_data_desc desc = { .type = NFT_DATA_VALUE, .size = sizeof(data), }; int err; err = nft_data_init(NULL, &data, &desc, tb[NFTA_CMP_DATA]); if (err < 0) return err; err = nft_parse_register_load(tb[NFTA_CMP_SREG], &priv->sreg, desc.len); if (err < 0) return err; desc.len *= BITS_PER_BYTE; priv->mask = nft_cmp_fast_mask(desc.len); priv->data = data.data[0] & priv->mask; priv->len = desc.len; priv->inv = ntohl(nla_get_be32(tb[NFTA_CMP_OP])) != NFT_CMP_EQ; return 0; } static int nft_cmp_fast_offload(struct nft_offload_ctx *ctx, struct nft_flow_rule *flow, const struct nft_expr *expr) { const struct nft_cmp_fast_expr *priv = nft_expr_priv(expr); struct nft_cmp_expr cmp = { .data = { .data = { [0] = priv->data, }, }, .sreg = priv->sreg, .len = priv->len / BITS_PER_BYTE, .op = priv->inv ? NFT_CMP_NEQ : NFT_CMP_EQ, }; return __nft_cmp_offload(ctx, flow, &cmp); } static int nft_cmp_fast_dump(struct sk_buff *skb, const struct nft_expr *expr, bool reset) { const struct nft_cmp_fast_expr *priv = nft_expr_priv(expr); enum nft_cmp_ops op = priv->inv ? NFT_CMP_NEQ : NFT_CMP_EQ; struct nft_data data; if (nft_dump_register(skb, NFTA_CMP_SREG, priv->sreg)) goto nla_put_failure; if (nla_put_be32(skb, NFTA_CMP_OP, htonl(op))) goto nla_put_failure; data.data[0] = priv->data; if (nft_data_dump(skb, NFTA_CMP_DATA, &data, NFT_DATA_VALUE, priv->len / BITS_PER_BYTE) < 0) goto nla_put_failure; return 0; nla_put_failure: return -1; } const struct nft_expr_ops nft_cmp_fast_ops = { .type = &nft_cmp_type, .size = NFT_EXPR_SIZE(sizeof(struct nft_cmp_fast_expr)), .eval = NULL, /* inlined */ .init = nft_cmp_fast_init, .dump = nft_cmp_fast_dump, .reduce = NFT_REDUCE_READONLY, .offload = nft_cmp_fast_offload, }; static u32 nft_cmp_mask(u32 bitlen) { return (__force u32)cpu_to_le32(~0U >> (sizeof(u32) * BITS_PER_BYTE - bitlen)); } static void nft_cmp16_fast_mask(struct nft_data *data, unsigned int bitlen) { int len = bitlen / BITS_PER_BYTE; int i, words = len / sizeof(u32); for (i = 0; i < words; i++) { data->data[i] = 0xffffffff; bitlen -= sizeof(u32) * BITS_PER_BYTE; } if (len % sizeof(u32)) data->data[i++] = nft_cmp_mask(bitlen); for (; i < 4; i++) data->data[i] = 0; } static int nft_cmp16_fast_init(const struct nft_ctx *ctx, const struct nft_expr *expr, const struct nlattr * const tb[]) { struct nft_cmp16_fast_expr *priv = nft_expr_priv(expr); struct nft_data_desc desc = { .type = NFT_DATA_VALUE, .size = sizeof(priv->data), }; int err; err = nft_data_init(NULL, &priv->data, &desc, tb[NFTA_CMP_DATA]); if (err < 0) return err; err = nft_parse_register_load(tb[NFTA_CMP_SREG], &priv->sreg, desc.len); if (err < 0) return err; nft_cmp16_fast_mask(&priv->mask, desc.len * BITS_PER_BYTE); priv->inv = ntohl(nla_get_be32(tb[NFTA_CMP_OP])) != NFT_CMP_EQ; priv->len = desc.len; return 0; } static int nft_cmp16_fast_offload(struct nft_offload_ctx *ctx, struct nft_flow_rule *flow, const struct nft_expr *expr) { const struct nft_cmp16_fast_expr *priv = nft_expr_priv(expr); struct nft_cmp_expr cmp = { .data = priv->data, .sreg = priv->sreg, .len = priv->len, .op = priv->inv ? NFT_CMP_NEQ : NFT_CMP_EQ, }; return __nft_cmp_offload(ctx, flow, &cmp); } static int nft_cmp16_fast_dump(struct sk_buff *skb, const struct nft_expr *expr, bool reset) { const struct nft_cmp16_fast_expr *priv = nft_expr_priv(expr); enum nft_cmp_ops op = priv->inv ? NFT_CMP_NEQ : NFT_CMP_EQ; if (nft_dump_register(skb, NFTA_CMP_SREG, priv->sreg)) goto nla_put_failure; if (nla_put_be32(skb, NFTA_CMP_OP, htonl(op))) goto nla_put_failure; if (nft_data_dump(skb, NFTA_CMP_DATA, &priv->data, NFT_DATA_VALUE, priv->len) < 0) goto nla_put_failure; return 0; nla_put_failure: return -1; } const struct nft_expr_ops nft_cmp16_fast_ops = { .type = &nft_cmp_type, .size = NFT_EXPR_SIZE(sizeof(struct nft_cmp16_fast_expr)), .eval = NULL, /* inlined */ .init = nft_cmp16_fast_init, .dump = nft_cmp16_fast_dump, .reduce = NFT_REDUCE_READONLY, .offload = nft_cmp16_fast_offload, }; static const struct nft_expr_ops * nft_cmp_select_ops(const struct nft_ctx *ctx, const struct nlattr * const tb[]) { struct nft_data data; struct nft_data_desc desc = { .type = NFT_DATA_VALUE, .size = sizeof(data), }; enum nft_cmp_ops op; u8 sreg; int err; if (tb[NFTA_CMP_SREG] == NULL || tb[NFTA_CMP_OP] == NULL || tb[NFTA_CMP_DATA] == NULL) return ERR_PTR(-EINVAL); op = ntohl(nla_get_be32(tb[NFTA_CMP_OP])); switch (op) { case NFT_CMP_EQ: case NFT_CMP_NEQ: case NFT_CMP_LT: case NFT_CMP_LTE: case NFT_CMP_GT: case NFT_CMP_GTE: break; default: return ERR_PTR(-EINVAL); } err = nft_data_init(NULL, &data, &desc, tb[NFTA_CMP_DATA]); if (err < 0) return ERR_PTR(err); sreg = ntohl(nla_get_be32(tb[NFTA_CMP_SREG])); if (op == NFT_CMP_EQ || op == NFT_CMP_NEQ) { if (desc.len <= sizeof(u32)) return &nft_cmp_fast_ops; else if (desc.len <= sizeof(data) && ((sreg >= NFT_REG_1 && sreg <= NFT_REG_4) || (sreg >= NFT_REG32_00 && sreg <= NFT_REG32_12 && sreg % 2 == 0))) return &nft_cmp16_fast_ops; } return &nft_cmp_ops; } struct nft_expr_type nft_cmp_type __read_mostly = { .name = "cmp", .select_ops = nft_cmp_select_ops, .policy = nft_cmp_policy, .maxattr = NFTA_CMP_MAX, .owner = THIS_MODULE, }; |