Jamal Hadi Salim | ef6980b | 2016-02-27 08:08:54 -0500 | [diff] [blame] | 1 | /* |
| 2 | * net/sched/ife.c Inter-FE action based on ForCES WG InterFE LFB |
| 3 | * |
| 4 | * Refer to: |
| 5 | * draft-ietf-forces-interfelfb-03 |
| 6 | * and |
| 7 | * netdev01 paper: |
| 8 | * "Distributing Linux Traffic Control Classifier-Action |
| 9 | * Subsystem" |
| 10 | * Authors: Jamal Hadi Salim and Damascene M. Joachimpillai |
| 11 | * |
| 12 | * This program is free software; you can redistribute it and/or |
| 13 | * modify it under the terms of the GNU General Public License |
| 14 | * as published by the Free Software Foundation; either version |
| 15 | * 2 of the License, or (at your option) any later version. |
| 16 | * |
| 17 | * copyright Jamal Hadi Salim (2015) |
| 18 | * |
| 19 | */ |
| 20 | |
| 21 | #include <linux/types.h> |
| 22 | #include <linux/kernel.h> |
| 23 | #include <linux/string.h> |
| 24 | #include <linux/errno.h> |
| 25 | #include <linux/skbuff.h> |
| 26 | #include <linux/rtnetlink.h> |
| 27 | #include <linux/module.h> |
| 28 | #include <linux/init.h> |
| 29 | #include <net/net_namespace.h> |
| 30 | #include <net/netlink.h> |
| 31 | #include <net/pkt_sched.h> |
| 32 | #include <uapi/linux/tc_act/tc_ife.h> |
| 33 | #include <net/tc_act/tc_ife.h> |
| 34 | #include <linux/etherdevice.h> |
| 35 | |
| 36 | #define IFE_TAB_MASK 15 |
| 37 | |
| 38 | static int ife_net_id; |
| 39 | static int max_metacnt = IFE_META_MAX + 1; |
| 40 | |
| 41 | static const struct nla_policy ife_policy[TCA_IFE_MAX + 1] = { |
| 42 | [TCA_IFE_PARMS] = { .len = sizeof(struct tc_ife)}, |
| 43 | [TCA_IFE_DMAC] = { .len = ETH_ALEN}, |
| 44 | [TCA_IFE_SMAC] = { .len = ETH_ALEN}, |
| 45 | [TCA_IFE_TYPE] = { .type = NLA_U16}, |
| 46 | }; |
| 47 | |
| 48 | /* Caller takes care of presenting data in network order |
| 49 | */ |
| 50 | int ife_tlv_meta_encode(void *skbdata, u16 attrtype, u16 dlen, const void *dval) |
| 51 | { |
| 52 | u32 *tlv = (u32 *)(skbdata); |
| 53 | u16 totlen = nla_total_size(dlen); /*alignment + hdr */ |
| 54 | char *dptr = (char *)tlv + NLA_HDRLEN; |
| 55 | u32 htlv = attrtype << 16 | totlen; |
| 56 | |
| 57 | *tlv = htonl(htlv); |
| 58 | memset(dptr, 0, totlen - NLA_HDRLEN); |
| 59 | memcpy(dptr, dval, dlen); |
| 60 | |
| 61 | return totlen; |
| 62 | } |
| 63 | EXPORT_SYMBOL_GPL(ife_tlv_meta_encode); |
| 64 | |
| 65 | int ife_get_meta_u32(struct sk_buff *skb, struct tcf_meta_info *mi) |
| 66 | { |
| 67 | if (mi->metaval) |
| 68 | return nla_put_u32(skb, mi->metaid, *(u32 *)mi->metaval); |
| 69 | else |
| 70 | return nla_put(skb, mi->metaid, 0, NULL); |
| 71 | } |
| 72 | EXPORT_SYMBOL_GPL(ife_get_meta_u32); |
| 73 | |
| 74 | int ife_check_meta_u32(u32 metaval, struct tcf_meta_info *mi) |
| 75 | { |
| 76 | if (metaval || mi->metaval) |
| 77 | return 8; /* T+L+V == 2+2+4 */ |
| 78 | |
| 79 | return 0; |
| 80 | } |
| 81 | EXPORT_SYMBOL_GPL(ife_check_meta_u32); |
| 82 | |
| 83 | int ife_encode_meta_u32(u32 metaval, void *skbdata, struct tcf_meta_info *mi) |
| 84 | { |
| 85 | u32 edata = metaval; |
| 86 | |
| 87 | if (mi->metaval) |
| 88 | edata = *(u32 *)mi->metaval; |
| 89 | else if (metaval) |
| 90 | edata = metaval; |
| 91 | |
| 92 | if (!edata) /* will not encode */ |
| 93 | return 0; |
| 94 | |
| 95 | edata = htonl(edata); |
| 96 | return ife_tlv_meta_encode(skbdata, mi->metaid, 4, &edata); |
| 97 | } |
| 98 | EXPORT_SYMBOL_GPL(ife_encode_meta_u32); |
| 99 | |
| 100 | int ife_get_meta_u16(struct sk_buff *skb, struct tcf_meta_info *mi) |
| 101 | { |
| 102 | if (mi->metaval) |
| 103 | return nla_put_u16(skb, mi->metaid, *(u16 *)mi->metaval); |
| 104 | else |
| 105 | return nla_put(skb, mi->metaid, 0, NULL); |
| 106 | } |
| 107 | EXPORT_SYMBOL_GPL(ife_get_meta_u16); |
| 108 | |
| 109 | int ife_alloc_meta_u32(struct tcf_meta_info *mi, void *metaval) |
| 110 | { |
WANG Cong | d1491fa | 2016-03-02 11:20:36 -0800 | [diff] [blame] | 111 | mi->metaval = kmemdup(metaval, sizeof(u32), GFP_KERNEL); |
Jamal Hadi Salim | ef6980b | 2016-02-27 08:08:54 -0500 | [diff] [blame] | 112 | if (!mi->metaval) |
| 113 | return -ENOMEM; |
| 114 | |
| 115 | return 0; |
| 116 | } |
| 117 | EXPORT_SYMBOL_GPL(ife_alloc_meta_u32); |
| 118 | |
| 119 | int ife_alloc_meta_u16(struct tcf_meta_info *mi, void *metaval) |
| 120 | { |
WANG Cong | d1491fa | 2016-03-02 11:20:36 -0800 | [diff] [blame] | 121 | mi->metaval = kmemdup(metaval, sizeof(u16), GFP_KERNEL); |
Jamal Hadi Salim | ef6980b | 2016-02-27 08:08:54 -0500 | [diff] [blame] | 122 | if (!mi->metaval) |
| 123 | return -ENOMEM; |
| 124 | |
| 125 | return 0; |
| 126 | } |
| 127 | EXPORT_SYMBOL_GPL(ife_alloc_meta_u16); |
| 128 | |
| 129 | void ife_release_meta_gen(struct tcf_meta_info *mi) |
| 130 | { |
| 131 | kfree(mi->metaval); |
| 132 | } |
| 133 | EXPORT_SYMBOL_GPL(ife_release_meta_gen); |
| 134 | |
| 135 | int ife_validate_meta_u32(void *val, int len) |
| 136 | { |
| 137 | if (len == 4) |
| 138 | return 0; |
| 139 | |
| 140 | return -EINVAL; |
| 141 | } |
| 142 | EXPORT_SYMBOL_GPL(ife_validate_meta_u32); |
| 143 | |
| 144 | int ife_validate_meta_u16(void *val, int len) |
| 145 | { |
| 146 | /* length will include padding */ |
| 147 | if (len == NLA_ALIGN(2)) |
| 148 | return 0; |
| 149 | |
| 150 | return -EINVAL; |
| 151 | } |
| 152 | EXPORT_SYMBOL_GPL(ife_validate_meta_u16); |
| 153 | |
| 154 | static LIST_HEAD(ifeoplist); |
| 155 | static DEFINE_RWLOCK(ife_mod_lock); |
| 156 | |
| 157 | static struct tcf_meta_ops *find_ife_oplist(u16 metaid) |
| 158 | { |
| 159 | struct tcf_meta_ops *o; |
| 160 | |
| 161 | read_lock(&ife_mod_lock); |
| 162 | list_for_each_entry(o, &ifeoplist, list) { |
| 163 | if (o->metaid == metaid) { |
| 164 | if (!try_module_get(o->owner)) |
| 165 | o = NULL; |
| 166 | read_unlock(&ife_mod_lock); |
| 167 | return o; |
| 168 | } |
| 169 | } |
| 170 | read_unlock(&ife_mod_lock); |
| 171 | |
| 172 | return NULL; |
| 173 | } |
| 174 | |
| 175 | int register_ife_op(struct tcf_meta_ops *mops) |
| 176 | { |
| 177 | struct tcf_meta_ops *m; |
| 178 | |
| 179 | if (!mops->metaid || !mops->metatype || !mops->name || |
| 180 | !mops->check_presence || !mops->encode || !mops->decode || |
| 181 | !mops->get || !mops->alloc) |
| 182 | return -EINVAL; |
| 183 | |
| 184 | write_lock(&ife_mod_lock); |
| 185 | |
| 186 | list_for_each_entry(m, &ifeoplist, list) { |
| 187 | if (m->metaid == mops->metaid || |
| 188 | (strcmp(mops->name, m->name) == 0)) { |
| 189 | write_unlock(&ife_mod_lock); |
| 190 | return -EEXIST; |
| 191 | } |
| 192 | } |
| 193 | |
| 194 | if (!mops->release) |
| 195 | mops->release = ife_release_meta_gen; |
| 196 | |
| 197 | list_add_tail(&mops->list, &ifeoplist); |
| 198 | write_unlock(&ife_mod_lock); |
| 199 | return 0; |
| 200 | } |
| 201 | EXPORT_SYMBOL_GPL(unregister_ife_op); |
| 202 | |
| 203 | int unregister_ife_op(struct tcf_meta_ops *mops) |
| 204 | { |
| 205 | struct tcf_meta_ops *m; |
| 206 | int err = -ENOENT; |
| 207 | |
| 208 | write_lock(&ife_mod_lock); |
| 209 | list_for_each_entry(m, &ifeoplist, list) { |
| 210 | if (m->metaid == mops->metaid) { |
| 211 | list_del(&mops->list); |
| 212 | err = 0; |
| 213 | break; |
| 214 | } |
| 215 | } |
| 216 | write_unlock(&ife_mod_lock); |
| 217 | |
| 218 | return err; |
| 219 | } |
| 220 | EXPORT_SYMBOL_GPL(register_ife_op); |
| 221 | |
| 222 | static int ife_validate_metatype(struct tcf_meta_ops *ops, void *val, int len) |
| 223 | { |
| 224 | int ret = 0; |
| 225 | /* XXX: unfortunately cant use nla_policy at this point |
| 226 | * because a length of 0 is valid in the case of |
| 227 | * "allow". "use" semantics do enforce for proper |
| 228 | * length and i couldve use nla_policy but it makes it hard |
| 229 | * to use it just for that.. |
| 230 | */ |
| 231 | if (ops->validate) |
| 232 | return ops->validate(val, len); |
| 233 | |
| 234 | if (ops->metatype == NLA_U32) |
| 235 | ret = ife_validate_meta_u32(val, len); |
| 236 | else if (ops->metatype == NLA_U16) |
| 237 | ret = ife_validate_meta_u16(val, len); |
| 238 | |
| 239 | return ret; |
| 240 | } |
| 241 | |
| 242 | /* called when adding new meta information |
| 243 | * under ife->tcf_lock |
| 244 | */ |
| 245 | static int load_metaops_and_vet(struct tcf_ife_info *ife, u32 metaid, |
| 246 | void *val, int len) |
| 247 | { |
| 248 | struct tcf_meta_ops *ops = find_ife_oplist(metaid); |
| 249 | int ret = 0; |
| 250 | |
| 251 | if (!ops) { |
| 252 | ret = -ENOENT; |
| 253 | #ifdef CONFIG_MODULES |
| 254 | spin_unlock_bh(&ife->tcf_lock); |
| 255 | rtnl_unlock(); |
| 256 | request_module("ifemeta%u", metaid); |
| 257 | rtnl_lock(); |
| 258 | spin_lock_bh(&ife->tcf_lock); |
| 259 | ops = find_ife_oplist(metaid); |
| 260 | #endif |
| 261 | } |
| 262 | |
| 263 | if (ops) { |
| 264 | ret = 0; |
| 265 | if (len) |
| 266 | ret = ife_validate_metatype(ops, val, len); |
| 267 | |
| 268 | module_put(ops->owner); |
| 269 | } |
| 270 | |
| 271 | return ret; |
| 272 | } |
| 273 | |
| 274 | /* called when adding new meta information |
| 275 | * under ife->tcf_lock |
| 276 | */ |
| 277 | static int add_metainfo(struct tcf_ife_info *ife, u32 metaid, void *metaval, |
| 278 | int len) |
| 279 | { |
| 280 | struct tcf_meta_info *mi = NULL; |
| 281 | struct tcf_meta_ops *ops = find_ife_oplist(metaid); |
| 282 | int ret = 0; |
| 283 | |
| 284 | if (!ops) |
| 285 | return -ENOENT; |
| 286 | |
| 287 | mi = kzalloc(sizeof(*mi), GFP_KERNEL); |
| 288 | if (!mi) { |
| 289 | /*put back what find_ife_oplist took */ |
| 290 | module_put(ops->owner); |
| 291 | return -ENOMEM; |
| 292 | } |
| 293 | |
| 294 | mi->metaid = metaid; |
| 295 | mi->ops = ops; |
| 296 | if (len > 0) { |
| 297 | ret = ops->alloc(mi, metaval); |
| 298 | if (ret != 0) { |
| 299 | kfree(mi); |
| 300 | module_put(ops->owner); |
| 301 | return ret; |
| 302 | } |
| 303 | } |
| 304 | |
| 305 | list_add_tail(&mi->metalist, &ife->metalist); |
| 306 | |
| 307 | return ret; |
| 308 | } |
| 309 | |
| 310 | static int use_all_metadata(struct tcf_ife_info *ife) |
| 311 | { |
| 312 | struct tcf_meta_ops *o; |
| 313 | int rc = 0; |
| 314 | int installed = 0; |
| 315 | |
| 316 | list_for_each_entry(o, &ifeoplist, list) { |
| 317 | rc = add_metainfo(ife, o->metaid, NULL, 0); |
| 318 | if (rc == 0) |
| 319 | installed += 1; |
| 320 | } |
| 321 | |
| 322 | if (installed) |
| 323 | return 0; |
| 324 | else |
| 325 | return -EINVAL; |
| 326 | } |
| 327 | |
| 328 | static int dump_metalist(struct sk_buff *skb, struct tcf_ife_info *ife) |
| 329 | { |
| 330 | struct tcf_meta_info *e; |
| 331 | struct nlattr *nest; |
| 332 | unsigned char *b = skb_tail_pointer(skb); |
| 333 | int total_encoded = 0; |
| 334 | |
| 335 | /*can only happen on decode */ |
| 336 | if (list_empty(&ife->metalist)) |
| 337 | return 0; |
| 338 | |
| 339 | nest = nla_nest_start(skb, TCA_IFE_METALST); |
| 340 | if (!nest) |
| 341 | goto out_nlmsg_trim; |
| 342 | |
| 343 | list_for_each_entry(e, &ife->metalist, metalist) { |
| 344 | if (!e->ops->get(skb, e)) |
| 345 | total_encoded += 1; |
| 346 | } |
| 347 | |
| 348 | if (!total_encoded) |
| 349 | goto out_nlmsg_trim; |
| 350 | |
| 351 | nla_nest_end(skb, nest); |
| 352 | |
| 353 | return 0; |
| 354 | |
| 355 | out_nlmsg_trim: |
| 356 | nlmsg_trim(skb, b); |
| 357 | return -1; |
| 358 | } |
| 359 | |
| 360 | /* under ife->tcf_lock */ |
| 361 | static void _tcf_ife_cleanup(struct tc_action *a, int bind) |
| 362 | { |
| 363 | struct tcf_ife_info *ife = a->priv; |
| 364 | struct tcf_meta_info *e, *n; |
| 365 | |
| 366 | list_for_each_entry_safe(e, n, &ife->metalist, metalist) { |
| 367 | module_put(e->ops->owner); |
| 368 | list_del(&e->metalist); |
| 369 | if (e->metaval) { |
| 370 | if (e->ops->release) |
| 371 | e->ops->release(e); |
| 372 | else |
| 373 | kfree(e->metaval); |
| 374 | } |
| 375 | kfree(e); |
| 376 | } |
| 377 | } |
| 378 | |
| 379 | static void tcf_ife_cleanup(struct tc_action *a, int bind) |
| 380 | { |
| 381 | struct tcf_ife_info *ife = a->priv; |
| 382 | |
| 383 | spin_lock_bh(&ife->tcf_lock); |
| 384 | _tcf_ife_cleanup(a, bind); |
| 385 | spin_unlock_bh(&ife->tcf_lock); |
| 386 | } |
| 387 | |
| 388 | /* under ife->tcf_lock */ |
| 389 | static int populate_metalist(struct tcf_ife_info *ife, struct nlattr **tb) |
| 390 | { |
| 391 | int len = 0; |
| 392 | int rc = 0; |
| 393 | int i = 0; |
| 394 | void *val; |
| 395 | |
| 396 | for (i = 1; i < max_metacnt; i++) { |
| 397 | if (tb[i]) { |
| 398 | val = nla_data(tb[i]); |
| 399 | len = nla_len(tb[i]); |
| 400 | |
| 401 | rc = load_metaops_and_vet(ife, i, val, len); |
| 402 | if (rc != 0) |
| 403 | return rc; |
| 404 | |
| 405 | rc = add_metainfo(ife, i, val, len); |
| 406 | if (rc) |
| 407 | return rc; |
| 408 | } |
| 409 | } |
| 410 | |
| 411 | return rc; |
| 412 | } |
| 413 | |
| 414 | static int tcf_ife_init(struct net *net, struct nlattr *nla, |
| 415 | struct nlattr *est, struct tc_action *a, |
| 416 | int ovr, int bind) |
| 417 | { |
| 418 | struct tc_action_net *tn = net_generic(net, ife_net_id); |
| 419 | struct nlattr *tb[TCA_IFE_MAX + 1]; |
| 420 | struct nlattr *tb2[IFE_META_MAX + 1]; |
| 421 | struct tcf_ife_info *ife; |
| 422 | struct tc_ife *parm; |
| 423 | u16 ife_type = 0; |
| 424 | u8 *daddr = NULL; |
| 425 | u8 *saddr = NULL; |
| 426 | int ret = 0; |
| 427 | int err; |
| 428 | |
| 429 | err = nla_parse_nested(tb, TCA_IFE_MAX, nla, ife_policy); |
| 430 | if (err < 0) |
| 431 | return err; |
| 432 | |
| 433 | if (!tb[TCA_IFE_PARMS]) |
| 434 | return -EINVAL; |
| 435 | |
| 436 | parm = nla_data(tb[TCA_IFE_PARMS]); |
| 437 | |
| 438 | if (parm->flags & IFE_ENCODE) { |
| 439 | /* Until we get issued the ethertype, we cant have |
| 440 | * a default.. |
| 441 | **/ |
| 442 | if (!tb[TCA_IFE_TYPE]) { |
| 443 | pr_info("You MUST pass etherype for encoding\n"); |
| 444 | return -EINVAL; |
| 445 | } |
| 446 | } |
| 447 | |
| 448 | if (!tcf_hash_check(tn, parm->index, a, bind)) { |
| 449 | ret = tcf_hash_create(tn, parm->index, est, a, sizeof(*ife), |
| 450 | bind, false); |
| 451 | if (ret) |
| 452 | return ret; |
| 453 | ret = ACT_P_CREATED; |
| 454 | } else { |
| 455 | if (bind) /* dont override defaults */ |
| 456 | return 0; |
| 457 | tcf_hash_release(a, bind); |
| 458 | if (!ovr) |
| 459 | return -EEXIST; |
| 460 | } |
| 461 | |
| 462 | ife = to_ife(a); |
| 463 | ife->flags = parm->flags; |
| 464 | |
| 465 | if (parm->flags & IFE_ENCODE) { |
| 466 | ife_type = nla_get_u16(tb[TCA_IFE_TYPE]); |
| 467 | if (tb[TCA_IFE_DMAC]) |
| 468 | daddr = nla_data(tb[TCA_IFE_DMAC]); |
| 469 | if (tb[TCA_IFE_SMAC]) |
| 470 | saddr = nla_data(tb[TCA_IFE_SMAC]); |
| 471 | } |
| 472 | |
| 473 | spin_lock_bh(&ife->tcf_lock); |
| 474 | ife->tcf_action = parm->action; |
| 475 | |
| 476 | if (parm->flags & IFE_ENCODE) { |
| 477 | if (daddr) |
| 478 | ether_addr_copy(ife->eth_dst, daddr); |
| 479 | else |
| 480 | eth_zero_addr(ife->eth_dst); |
| 481 | |
| 482 | if (saddr) |
| 483 | ether_addr_copy(ife->eth_src, saddr); |
| 484 | else |
| 485 | eth_zero_addr(ife->eth_src); |
| 486 | |
| 487 | ife->eth_type = ife_type; |
| 488 | } |
| 489 | |
| 490 | if (ret == ACT_P_CREATED) |
| 491 | INIT_LIST_HEAD(&ife->metalist); |
| 492 | |
| 493 | if (tb[TCA_IFE_METALST]) { |
| 494 | err = nla_parse_nested(tb2, IFE_META_MAX, tb[TCA_IFE_METALST], |
| 495 | NULL); |
| 496 | if (err) { |
| 497 | metadata_parse_err: |
| 498 | if (ret == ACT_P_CREATED) |
| 499 | _tcf_ife_cleanup(a, bind); |
| 500 | |
| 501 | spin_unlock_bh(&ife->tcf_lock); |
| 502 | return err; |
| 503 | } |
| 504 | |
| 505 | err = populate_metalist(ife, tb2); |
| 506 | if (err) |
| 507 | goto metadata_parse_err; |
| 508 | |
| 509 | } else { |
| 510 | /* if no passed metadata allow list or passed allow-all |
| 511 | * then here we process by adding as many supported metadatum |
| 512 | * as we can. You better have at least one else we are |
| 513 | * going to bail out |
| 514 | */ |
| 515 | err = use_all_metadata(ife); |
| 516 | if (err) { |
| 517 | if (ret == ACT_P_CREATED) |
| 518 | _tcf_ife_cleanup(a, bind); |
| 519 | |
| 520 | spin_unlock_bh(&ife->tcf_lock); |
| 521 | return err; |
| 522 | } |
| 523 | } |
| 524 | |
| 525 | spin_unlock_bh(&ife->tcf_lock); |
| 526 | |
| 527 | if (ret == ACT_P_CREATED) |
| 528 | tcf_hash_insert(tn, a); |
| 529 | |
| 530 | return ret; |
| 531 | } |
| 532 | |
| 533 | static int tcf_ife_dump(struct sk_buff *skb, struct tc_action *a, int bind, |
| 534 | int ref) |
| 535 | { |
| 536 | unsigned char *b = skb_tail_pointer(skb); |
| 537 | struct tcf_ife_info *ife = a->priv; |
| 538 | struct tc_ife opt = { |
| 539 | .index = ife->tcf_index, |
| 540 | .refcnt = ife->tcf_refcnt - ref, |
| 541 | .bindcnt = ife->tcf_bindcnt - bind, |
| 542 | .action = ife->tcf_action, |
| 543 | .flags = ife->flags, |
| 544 | }; |
| 545 | struct tcf_t t; |
| 546 | |
| 547 | if (nla_put(skb, TCA_IFE_PARMS, sizeof(opt), &opt)) |
| 548 | goto nla_put_failure; |
| 549 | |
| 550 | t.install = jiffies_to_clock_t(jiffies - ife->tcf_tm.install); |
| 551 | t.lastuse = jiffies_to_clock_t(jiffies - ife->tcf_tm.lastuse); |
| 552 | t.expires = jiffies_to_clock_t(ife->tcf_tm.expires); |
| 553 | if (nla_put(skb, TCA_IFE_TM, sizeof(t), &t)) |
| 554 | goto nla_put_failure; |
| 555 | |
| 556 | if (!is_zero_ether_addr(ife->eth_dst)) { |
| 557 | if (nla_put(skb, TCA_IFE_DMAC, ETH_ALEN, ife->eth_dst)) |
| 558 | goto nla_put_failure; |
| 559 | } |
| 560 | |
| 561 | if (!is_zero_ether_addr(ife->eth_src)) { |
| 562 | if (nla_put(skb, TCA_IFE_SMAC, ETH_ALEN, ife->eth_src)) |
| 563 | goto nla_put_failure; |
| 564 | } |
| 565 | |
| 566 | if (nla_put(skb, TCA_IFE_TYPE, 2, &ife->eth_type)) |
| 567 | goto nla_put_failure; |
| 568 | |
| 569 | if (dump_metalist(skb, ife)) { |
| 570 | /*ignore failure to dump metalist */ |
| 571 | pr_info("Failed to dump metalist\n"); |
| 572 | } |
| 573 | |
| 574 | return skb->len; |
| 575 | |
| 576 | nla_put_failure: |
| 577 | nlmsg_trim(skb, b); |
| 578 | return -1; |
| 579 | } |
| 580 | |
| 581 | int find_decode_metaid(struct sk_buff *skb, struct tcf_ife_info *ife, |
| 582 | u16 metaid, u16 mlen, void *mdata) |
| 583 | { |
| 584 | struct tcf_meta_info *e; |
| 585 | |
| 586 | /* XXX: use hash to speed up */ |
| 587 | list_for_each_entry(e, &ife->metalist, metalist) { |
| 588 | if (metaid == e->metaid) { |
| 589 | if (e->ops) { |
| 590 | /* We check for decode presence already */ |
| 591 | return e->ops->decode(skb, mdata, mlen); |
| 592 | } |
| 593 | } |
| 594 | } |
| 595 | |
| 596 | return 0; |
| 597 | } |
| 598 | |
| 599 | struct ifeheadr { |
| 600 | __be16 metalen; |
| 601 | u8 tlv_data[]; |
| 602 | }; |
| 603 | |
| 604 | struct meta_tlvhdr { |
| 605 | __be16 type; |
| 606 | __be16 len; |
| 607 | }; |
| 608 | |
| 609 | static int tcf_ife_decode(struct sk_buff *skb, const struct tc_action *a, |
| 610 | struct tcf_result *res) |
| 611 | { |
| 612 | struct tcf_ife_info *ife = a->priv; |
| 613 | int action = ife->tcf_action; |
| 614 | struct ifeheadr *ifehdr = (struct ifeheadr *)skb->data; |
| 615 | u16 ifehdrln = ifehdr->metalen; |
| 616 | struct meta_tlvhdr *tlv = (struct meta_tlvhdr *)(ifehdr->tlv_data); |
| 617 | |
| 618 | spin_lock(&ife->tcf_lock); |
| 619 | bstats_update(&ife->tcf_bstats, skb); |
| 620 | ife->tcf_tm.lastuse = jiffies; |
| 621 | spin_unlock(&ife->tcf_lock); |
| 622 | |
| 623 | ifehdrln = ntohs(ifehdrln); |
| 624 | if (unlikely(!pskb_may_pull(skb, ifehdrln))) { |
| 625 | spin_lock(&ife->tcf_lock); |
| 626 | ife->tcf_qstats.drops++; |
| 627 | spin_unlock(&ife->tcf_lock); |
| 628 | return TC_ACT_SHOT; |
| 629 | } |
| 630 | |
| 631 | skb_set_mac_header(skb, ifehdrln); |
| 632 | __skb_pull(skb, ifehdrln); |
| 633 | skb->protocol = eth_type_trans(skb, skb->dev); |
| 634 | ifehdrln -= IFE_METAHDRLEN; |
| 635 | |
| 636 | while (ifehdrln > 0) { |
| 637 | u8 *tlvdata = (u8 *)tlv; |
| 638 | u16 mtype = tlv->type; |
| 639 | u16 mlen = tlv->len; |
| 640 | |
| 641 | mtype = ntohs(mtype); |
| 642 | mlen = ntohs(mlen); |
| 643 | |
| 644 | if (find_decode_metaid(skb, ife, mtype, (mlen - 4), |
| 645 | (void *)(tlvdata + 4))) { |
| 646 | /* abuse overlimits to count when we receive metadata |
| 647 | * but dont have an ops for it |
| 648 | */ |
| 649 | pr_info_ratelimited("Unknown metaid %d alnlen %d\n", |
| 650 | mtype, mlen); |
| 651 | ife->tcf_qstats.overlimits++; |
| 652 | } |
| 653 | |
| 654 | tlvdata += mlen; |
| 655 | ifehdrln -= mlen; |
| 656 | tlv = (struct meta_tlvhdr *)tlvdata; |
| 657 | } |
| 658 | |
| 659 | skb_reset_network_header(skb); |
| 660 | return action; |
| 661 | } |
| 662 | |
| 663 | /*XXX: check if we can do this at install time instead of current |
| 664 | * send data path |
| 665 | **/ |
| 666 | static int ife_get_sz(struct sk_buff *skb, struct tcf_ife_info *ife) |
| 667 | { |
| 668 | struct tcf_meta_info *e, *n; |
| 669 | int tot_run_sz = 0, run_sz = 0; |
| 670 | |
| 671 | list_for_each_entry_safe(e, n, &ife->metalist, metalist) { |
| 672 | if (e->ops->check_presence) { |
| 673 | run_sz = e->ops->check_presence(skb, e); |
| 674 | tot_run_sz += run_sz; |
| 675 | } |
| 676 | } |
| 677 | |
| 678 | return tot_run_sz; |
| 679 | } |
| 680 | |
| 681 | static int tcf_ife_encode(struct sk_buff *skb, const struct tc_action *a, |
| 682 | struct tcf_result *res) |
| 683 | { |
| 684 | struct tcf_ife_info *ife = a->priv; |
| 685 | int action = ife->tcf_action; |
| 686 | struct ethhdr *oethh; /* outer ether header */ |
| 687 | struct ethhdr *iethh; /* inner eth header */ |
| 688 | struct tcf_meta_info *e; |
| 689 | /* |
| 690 | OUTERHDR:TOTMETALEN:{TLVHDR:Metadatum:TLVHDR..}:ORIGDATA |
| 691 | where ORIGDATA = original ethernet header ... |
| 692 | */ |
| 693 | u16 metalen = ife_get_sz(skb, ife); |
| 694 | int hdrm = metalen + skb->dev->hard_header_len + IFE_METAHDRLEN; |
| 695 | unsigned int skboff = skb->dev->hard_header_len; |
| 696 | u32 at = G_TC_AT(skb->tc_verd); |
| 697 | int new_len = skb->len + hdrm; |
| 698 | bool exceed_mtu = false; |
| 699 | int err; |
| 700 | |
| 701 | if (at & AT_EGRESS) { |
| 702 | if (new_len > skb->dev->mtu) |
| 703 | exceed_mtu = true; |
| 704 | } |
| 705 | |
| 706 | spin_lock(&ife->tcf_lock); |
| 707 | bstats_update(&ife->tcf_bstats, skb); |
| 708 | ife->tcf_tm.lastuse = jiffies; |
| 709 | |
| 710 | if (!metalen) { /* no metadata to send */ |
| 711 | /* abuse overlimits to count when we allow packet |
| 712 | * with no metadata |
| 713 | */ |
| 714 | ife->tcf_qstats.overlimits++; |
| 715 | spin_unlock(&ife->tcf_lock); |
| 716 | return action; |
| 717 | } |
| 718 | /* could be stupid policy setup or mtu config |
| 719 | * so lets be conservative.. */ |
| 720 | if ((action == TC_ACT_SHOT) || exceed_mtu) { |
| 721 | ife->tcf_qstats.drops++; |
| 722 | spin_unlock(&ife->tcf_lock); |
| 723 | return TC_ACT_SHOT; |
| 724 | } |
| 725 | |
| 726 | iethh = eth_hdr(skb); |
| 727 | |
| 728 | err = skb_cow_head(skb, hdrm); |
| 729 | if (unlikely(err)) { |
| 730 | ife->tcf_qstats.drops++; |
| 731 | spin_unlock(&ife->tcf_lock); |
| 732 | return TC_ACT_SHOT; |
| 733 | } |
| 734 | |
| 735 | if (!(at & AT_EGRESS)) |
| 736 | skb_push(skb, skb->dev->hard_header_len); |
| 737 | |
| 738 | __skb_push(skb, hdrm); |
| 739 | memcpy(skb->data, iethh, skb->mac_len); |
| 740 | skb_reset_mac_header(skb); |
| 741 | oethh = eth_hdr(skb); |
| 742 | |
| 743 | /*total metadata length */ |
| 744 | metalen += IFE_METAHDRLEN; |
| 745 | metalen = htons(metalen); |
| 746 | memcpy((skb->data + skboff), &metalen, IFE_METAHDRLEN); |
| 747 | skboff += IFE_METAHDRLEN; |
| 748 | |
| 749 | /* XXX: we dont have a clever way of telling encode to |
| 750 | * not repeat some of the computations that are done by |
| 751 | * ops->presence_check... |
| 752 | */ |
| 753 | list_for_each_entry(e, &ife->metalist, metalist) { |
| 754 | if (e->ops->encode) { |
| 755 | err = e->ops->encode(skb, (void *)(skb->data + skboff), |
| 756 | e); |
| 757 | } |
| 758 | if (err < 0) { |
| 759 | /* too corrupt to keep around if overwritten */ |
| 760 | ife->tcf_qstats.drops++; |
| 761 | spin_unlock(&ife->tcf_lock); |
| 762 | return TC_ACT_SHOT; |
| 763 | } |
| 764 | skboff += err; |
| 765 | } |
| 766 | |
| 767 | if (!is_zero_ether_addr(ife->eth_src)) |
| 768 | ether_addr_copy(oethh->h_source, ife->eth_src); |
| 769 | else |
| 770 | ether_addr_copy(oethh->h_source, iethh->h_source); |
| 771 | if (!is_zero_ether_addr(ife->eth_dst)) |
| 772 | ether_addr_copy(oethh->h_dest, ife->eth_dst); |
| 773 | else |
| 774 | ether_addr_copy(oethh->h_dest, iethh->h_dest); |
| 775 | oethh->h_proto = htons(ife->eth_type); |
| 776 | |
| 777 | if (!(at & AT_EGRESS)) |
| 778 | skb_pull(skb, skb->dev->hard_header_len); |
| 779 | |
| 780 | spin_unlock(&ife->tcf_lock); |
| 781 | |
| 782 | return action; |
| 783 | } |
| 784 | |
| 785 | static int tcf_ife_act(struct sk_buff *skb, const struct tc_action *a, |
| 786 | struct tcf_result *res) |
| 787 | { |
| 788 | struct tcf_ife_info *ife = a->priv; |
| 789 | |
| 790 | if (ife->flags & IFE_ENCODE) |
| 791 | return tcf_ife_encode(skb, a, res); |
| 792 | |
| 793 | if (!(ife->flags & IFE_ENCODE)) |
| 794 | return tcf_ife_decode(skb, a, res); |
| 795 | |
| 796 | pr_info_ratelimited("unknown failure(policy neither de/encode\n"); |
| 797 | spin_lock(&ife->tcf_lock); |
| 798 | bstats_update(&ife->tcf_bstats, skb); |
| 799 | ife->tcf_tm.lastuse = jiffies; |
| 800 | ife->tcf_qstats.drops++; |
| 801 | spin_unlock(&ife->tcf_lock); |
| 802 | |
| 803 | return TC_ACT_SHOT; |
| 804 | } |
| 805 | |
| 806 | static int tcf_ife_walker(struct net *net, struct sk_buff *skb, |
| 807 | struct netlink_callback *cb, int type, |
| 808 | struct tc_action *a) |
| 809 | { |
| 810 | struct tc_action_net *tn = net_generic(net, ife_net_id); |
| 811 | |
| 812 | return tcf_generic_walker(tn, skb, cb, type, a); |
| 813 | } |
| 814 | |
| 815 | static int tcf_ife_search(struct net *net, struct tc_action *a, u32 index) |
| 816 | { |
| 817 | struct tc_action_net *tn = net_generic(net, ife_net_id); |
| 818 | |
| 819 | return tcf_hash_search(tn, a, index); |
| 820 | } |
| 821 | |
| 822 | static struct tc_action_ops act_ife_ops = { |
| 823 | .kind = "ife", |
| 824 | .type = TCA_ACT_IFE, |
| 825 | .owner = THIS_MODULE, |
| 826 | .act = tcf_ife_act, |
| 827 | .dump = tcf_ife_dump, |
| 828 | .cleanup = tcf_ife_cleanup, |
| 829 | .init = tcf_ife_init, |
| 830 | .walk = tcf_ife_walker, |
| 831 | .lookup = tcf_ife_search, |
| 832 | }; |
| 833 | |
| 834 | static __net_init int ife_init_net(struct net *net) |
| 835 | { |
| 836 | struct tc_action_net *tn = net_generic(net, ife_net_id); |
| 837 | |
| 838 | return tc_action_net_init(tn, &act_ife_ops, IFE_TAB_MASK); |
| 839 | } |
| 840 | |
| 841 | static void __net_exit ife_exit_net(struct net *net) |
| 842 | { |
| 843 | struct tc_action_net *tn = net_generic(net, ife_net_id); |
| 844 | |
| 845 | tc_action_net_exit(tn); |
| 846 | } |
| 847 | |
| 848 | static struct pernet_operations ife_net_ops = { |
| 849 | .init = ife_init_net, |
| 850 | .exit = ife_exit_net, |
| 851 | .id = &ife_net_id, |
| 852 | .size = sizeof(struct tc_action_net), |
| 853 | }; |
| 854 | |
| 855 | static int __init ife_init_module(void) |
| 856 | { |
| 857 | return tcf_register_action(&act_ife_ops, &ife_net_ops); |
| 858 | } |
| 859 | |
| 860 | static void __exit ife_cleanup_module(void) |
| 861 | { |
| 862 | tcf_unregister_action(&act_ife_ops, &ife_net_ops); |
| 863 | } |
| 864 | |
| 865 | module_init(ife_init_module); |
| 866 | module_exit(ife_cleanup_module); |
| 867 | |
| 868 | MODULE_AUTHOR("Jamal Hadi Salim(2015)"); |
| 869 | MODULE_DESCRIPTION("Inter-FE LFB action"); |
| 870 | MODULE_LICENSE("GPL"); |