net/sched/act_skbedit.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (c) 2008, Intel Corporation.
   4  *
   5  * Author: Alexander Duyck <alexander.h.duyck@intel.com>
   6  */
   7
   8 #include <linux/module.h>
   9 #include <linux/init.h>
  10 #include <linux/kernel.h>
  11 #include <linux/skbuff.h>
  12 #include <linux/rtnetlink.h>
  13 #include <net/netlink.h>
  14 #include <net/pkt_sched.h>
  15 #include <net/ip.h>
  16 #include <net/ipv6.h>
  17 #include <net/dsfield.h>
  18 #include <net/pkt_cls.h>
  19 #include <net/tc_wrapper.h>
  20
  21 #include <linux/tc_act/tc_skbedit.h>
  22 #include <net/tc_act/tc_skbedit.h>
  23
  24 static struct tc_action_ops act_skbedit_ops;
  25
  26 static u16 tcf_skbedit_hash(struct tcf_skbedit_params *params,
  27                             struct sk_buff *skb)
  28 {
  29         u16 queue_mapping = params->queue_mapping;
  30
  31         if (params->flags & SKBEDIT_F_TXQ_SKBHASH) {
  32                 u32 hash = skb_get_hash(skb);
  33
  34                 queue_mapping += hash % params->mapping_mod;
  35         }
  36
  37         return netdev_cap_txqueue(skb->dev, queue_mapping);
  38 }
  39
  40 TC_INDIRECT_SCOPE int tcf_skbedit_act(struct sk_buff *skb,
  41                                       const struct tc_action *a,
  42                                       struct tcf_result *res)
  43 {
  44         struct tcf_skbedit *d = to_skbedit(a);
  45         struct tcf_skbedit_params *params;
  46         int action;
  47
  48         tcf_lastuse_update(&d->tcf_tm);
  49         bstats_update(this_cpu_ptr(d->common.cpu_bstats), skb);
  50
  51         params = rcu_dereference_bh(d->params);
  52         action = READ_ONCE(d->tcf_action);
  53
  54         if (params->flags & SKBEDIT_F_PRIORITY)
  55                 skb->priority = params->priority;
  56         if (params->flags & SKBEDIT_F_INHERITDSFIELD) {
  57                 int wlen = skb_network_offset(skb);
  58
  59                 switch (skb_protocol(skb, true)) {
  60                 case htons(ETH_P_IP):
  61                         wlen += sizeof(struct iphdr);
  62                         if (!pskb_may_pull(skb, wlen))
  63                                 goto err;
  64                         skb->priority = ipv4_get_dsfield(ip_hdr(skb)) >> 2;
  65                         break;
  66
  67                 case htons(ETH_P_IPV6):
  68                         wlen += sizeof(struct ipv6hdr);
  69                         if (!pskb_may_pull(skb, wlen))
  70                                 goto err;
  71                         skb->priority = ipv6_get_dsfield(ipv6_hdr(skb)) >> 2;
  72                         break;
  73                 }
  74         }
  75         if (params->flags & SKBEDIT_F_QUEUE_MAPPING &&
  76             skb->dev->real_num_tx_queues > params->queue_mapping) {
  77 #ifdef CONFIG_NET_EGRESS
  78                 netdev_xmit_skip_txqueue(true);
  79 #endif
  80                 skb_set_queue_mapping(skb, tcf_skbedit_hash(params, skb));
  81         }
  82         if (params->flags & SKBEDIT_F_MARK) {
  83                 skb->mark &= ~params->mask;
  84                 skb->mark |= params->mark & params->mask;
  85         }
  86         if (params->flags & SKBEDIT_F_PTYPE)
  87                 skb->pkt_type = params->ptype;
  88         return action;
  89
  90 err:
  91         qstats_drop_inc(this_cpu_ptr(d->common.cpu_qstats));
  92         return TC_ACT_SHOT;
  93 }
  94
  95 static void tcf_skbedit_stats_update(struct tc_action *a, u64 bytes,
  96                                      u64 packets, u64 drops,
  97                                      u64 lastuse, bool hw)
  98 {
  99         struct tcf_skbedit *d = to_skbedit(a);
 100         struct tcf_t *tm = &d->tcf_tm;
 101
 102         tcf_action_update_stats(a, bytes, packets, drops, hw);
 103         tm->lastuse = max_t(u64, tm->lastuse, lastuse);
 104 }
 105
 106 static const struct nla_policy skbedit_policy[TCA_SKBEDIT_MAX + 1] = {
 107         [TCA_SKBEDIT_PARMS]             = { .len = sizeof(struct tc_skbedit) },
 108         [TCA_SKBEDIT_PRIORITY]          = { .len = sizeof(u32) },
 109         [TCA_SKBEDIT_QUEUE_MAPPING]     = { .len = sizeof(u16) },
 110         [TCA_SKBEDIT_MARK]              = { .len = sizeof(u32) },
 111         [TCA_SKBEDIT_PTYPE]             = { .len = sizeof(u16) },
 112         [TCA_SKBEDIT_MASK]              = { .len = sizeof(u32) },
 113         [TCA_SKBEDIT_FLAGS]             = { .len = sizeof(u64) },
 114         [TCA_SKBEDIT_QUEUE_MAPPING_MAX] = { .len = sizeof(u16) },
 115 };
 116
 117 static int tcf_skbedit_init(struct net *net, struct nlattr *nla,
 118                             struct nlattr *est, struct tc_action **a,
 119                             struct tcf_proto *tp, u32 act_flags,
 120                             struct netlink_ext_ack *extack)
 121 {
 122         struct tc_action_net *tn = net_generic(net, act_skbedit_ops.net_id);
 123         bool bind = act_flags & TCA_ACT_FLAGS_BIND;
 124         struct tcf_skbedit_params *params_new;
 125         struct nlattr *tb[TCA_SKBEDIT_MAX + 1];
 126         struct tcf_chain *goto_ch = NULL;
 127         struct tc_skbedit *parm;
 128         struct tcf_skbedit *d;
 129         u32 flags = 0, *priority = NULL, *mark = NULL, *mask = NULL;
 130         u16 *queue_mapping = NULL, *ptype = NULL;
 131         u16 mapping_mod = 1;
 132         bool exists = false;
 133         int ret = 0, err;
 134         u32 index;
 135
 136         if (nla == NULL)
 137                 return -EINVAL;
 138
 139         err = nla_parse_nested_deprecated(tb, TCA_SKBEDIT_MAX, nla,
 140                                           skbedit_policy, NULL);
 141         if (err < 0)
 142                 return err;
 143
 144         if (tb[TCA_SKBEDIT_PARMS] == NULL)
 145                 return -EINVAL;
 146
 147         if (tb[TCA_SKBEDIT_PRIORITY] != NULL) {
 148                 flags |= SKBEDIT_F_PRIORITY;
 149                 priority = nla_data(tb[TCA_SKBEDIT_PRIORITY]);
 150         }
 151
 152         if (tb[TCA_SKBEDIT_QUEUE_MAPPING] != NULL) {
 153                 if (is_tcf_skbedit_ingress(act_flags) &&
 154                     !(act_flags & TCA_ACT_FLAGS_SKIP_SW)) {
 155                         NL_SET_ERR_MSG_MOD(extack, "\"queue_mapping\" option on receive side is hardware only, use skip_sw");
 156                         return -EOPNOTSUPP;
 157                 }
 158                 flags |= SKBEDIT_F_QUEUE_MAPPING;
 159                 queue_mapping = nla_data(tb[TCA_SKBEDIT_QUEUE_MAPPING]);
 160         }
 161
 162         if (tb[TCA_SKBEDIT_PTYPE] != NULL) {
 163                 ptype = nla_data(tb[TCA_SKBEDIT_PTYPE]);
 164                 if (!skb_pkt_type_ok(*ptype))
 165                         return -EINVAL;
 166                 flags |= SKBEDIT_F_PTYPE;
 167         }
 168
 169         if (tb[TCA_SKBEDIT_MARK] != NULL) {
 170                 flags |= SKBEDIT_F_MARK;
 171                 mark = nla_data(tb[TCA_SKBEDIT_MARK]);
 172         }
 173
 174         if (tb[TCA_SKBEDIT_MASK] != NULL) {
 175                 flags |= SKBEDIT_F_MASK;
 176                 mask = nla_data(tb[TCA_SKBEDIT_MASK]);
 177         }
 178
 179         if (tb[TCA_SKBEDIT_FLAGS] != NULL) {
 180                 u64 *pure_flags = nla_data(tb[TCA_SKBEDIT_FLAGS]);
 181
 182                 if (*pure_flags & SKBEDIT_F_TXQ_SKBHASH) {
 183                         u16 *queue_mapping_max;
 184
 185                         if (!tb[TCA_SKBEDIT_QUEUE_MAPPING] ||
 186                             !tb[TCA_SKBEDIT_QUEUE_MAPPING_MAX]) {
 187                                 NL_SET_ERR_MSG_MOD(extack, "Missing required range of queue_mapping.");
 188                                 return -EINVAL;
 189                         }
 190
 191                         queue_mapping_max =
 192                                 nla_data(tb[TCA_SKBEDIT_QUEUE_MAPPING_MAX]);
 193                         if (*queue_mapping_max < *queue_mapping) {
 194                                 NL_SET_ERR_MSG_MOD(extack, "The range of queue_mapping is invalid, max < min.");
 195                                 return -EINVAL;
 196                         }
 197
 198                         mapping_mod = *queue_mapping_max - *queue_mapping + 1;
 199                         flags |= SKBEDIT_F_TXQ_SKBHASH;
 200                 }
 201                 if (*pure_flags & SKBEDIT_F_INHERITDSFIELD)
 202                         flags |= SKBEDIT_F_INHERITDSFIELD;
 203         }
 204
 205         parm = nla_data(tb[TCA_SKBEDIT_PARMS]);
 206         index = parm->index;
 207         err = tcf_idr_check_alloc(tn, &index, a, bind);
 208         if (err < 0)
 209                 return err;
 210         exists = err;
 211         if (exists && bind)
 212                 return 0;
 213
 214         if (!flags) {
 215                 if (exists)
 216                         tcf_idr_release(*a, bind);
 217                 else
 218                         tcf_idr_cleanup(tn, index);
 219                 return -EINVAL;
 220         }
 221
 222         if (!exists) {
 223                 ret = tcf_idr_create(tn, index, est, a,
 224                                      &act_skbedit_ops, bind, true, act_flags);
 225                 if (ret) {
 226                         tcf_idr_cleanup(tn, index);
 227                         return ret;
 228                 }
 229
 230                 d = to_skbedit(*a);
 231                 ret = ACT_P_CREATED;
 232         } else {
 233                 d = to_skbedit(*a);
 234                 if (!(act_flags & TCA_ACT_FLAGS_REPLACE)) {
 235                         tcf_idr_release(*a, bind);
 236                         return -EEXIST;
 237                 }
 238         }
 239         err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
 240         if (err < 0)
 241                 goto release_idr;
 242
 243         params_new = kzalloc(sizeof(*params_new), GFP_KERNEL);
 244         if (unlikely(!params_new)) {
 245                 err = -ENOMEM;
 246                 goto put_chain;
 247         }
 248
 249         params_new->flags = flags;
 250         if (flags & SKBEDIT_F_PRIORITY)
 251                 params_new->priority = *priority;
 252         if (flags & SKBEDIT_F_QUEUE_MAPPING) {
 253                 params_new->queue_mapping = *queue_mapping;
 254                 params_new->mapping_mod = mapping_mod;
 255         }
 256         if (flags & SKBEDIT_F_MARK)
 257                 params_new->mark = *mark;
 258         if (flags & SKBEDIT_F_PTYPE)
 259                 params_new->ptype = *ptype;
 260         /* default behaviour is to use all the bits */
 261         params_new->mask = 0xffffffff;
 262         if (flags & SKBEDIT_F_MASK)
 263                 params_new->mask = *mask;
 264
 265         spin_lock_bh(&d->tcf_lock);
 266         goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
 267         params_new = rcu_replace_pointer(d->params, params_new,
 268                                          lockdep_is_held(&d->tcf_lock));
 269         spin_unlock_bh(&d->tcf_lock);
 270         if (params_new)
 271                 kfree_rcu(params_new, rcu);
 272         if (goto_ch)
 273                 tcf_chain_put_by_act(goto_ch);
 274
 275         return ret;
 276 put_chain:
 277         if (goto_ch)
 278                 tcf_chain_put_by_act(goto_ch);
 279 release_idr:
 280         tcf_idr_release(*a, bind);
 281         return err;
 282 }
 283
 284 static int tcf_skbedit_dump(struct sk_buff *skb, struct tc_action *a,
 285                             int bind, int ref)
 286 {
 287         unsigned char *b = skb_tail_pointer(skb);
 288         struct tcf_skbedit *d = to_skbedit(a);
 289         struct tcf_skbedit_params *params;
 290         struct tc_skbedit opt = {
 291                 .index   = d->tcf_index,
 292                 .refcnt  = refcount_read(&d->tcf_refcnt) - ref,
 293                 .bindcnt = atomic_read(&d->tcf_bindcnt) - bind,
 294         };
 295         u64 pure_flags = 0;
 296         struct tcf_t t;
 297
 298         spin_lock_bh(&d->tcf_lock);
 299         params = rcu_dereference_protected(d->params,
 300                                            lockdep_is_held(&d->tcf_lock));
 301         opt.action = d->tcf_action;
 302
 303         if (nla_put(skb, TCA_SKBEDIT_PARMS, sizeof(opt), &opt))
 304                 goto nla_put_failure;
 305         if ((params->flags & SKBEDIT_F_PRIORITY) &&
 306             nla_put_u32(skb, TCA_SKBEDIT_PRIORITY, params->priority))
 307                 goto nla_put_failure;
 308         if ((params->flags & SKBEDIT_F_QUEUE_MAPPING) &&
 309             nla_put_u16(skb, TCA_SKBEDIT_QUEUE_MAPPING, params->queue_mapping))
 310                 goto nla_put_failure;
 311         if ((params->flags & SKBEDIT_F_MARK) &&
 312             nla_put_u32(skb, TCA_SKBEDIT_MARK, params->mark))
 313                 goto nla_put_failure;
 314         if ((params->flags & SKBEDIT_F_PTYPE) &&
 315             nla_put_u16(skb, TCA_SKBEDIT_PTYPE, params->ptype))
 316                 goto nla_put_failure;
 317         if ((params->flags & SKBEDIT_F_MASK) &&
 318             nla_put_u32(skb, TCA_SKBEDIT_MASK, params->mask))
 319                 goto nla_put_failure;
 320         if (params->flags & SKBEDIT_F_INHERITDSFIELD)
 321                 pure_flags |= SKBEDIT_F_INHERITDSFIELD;
 322         if (params->flags & SKBEDIT_F_TXQ_SKBHASH) {
 323                 if (nla_put_u16(skb, TCA_SKBEDIT_QUEUE_MAPPING_MAX,
 324                                 params->queue_mapping + params->mapping_mod - 1))
 325                         goto nla_put_failure;
 326
 327                 pure_flags |= SKBEDIT_F_TXQ_SKBHASH;
 328         }
 329         if (pure_flags != 0 &&
 330             nla_put(skb, TCA_SKBEDIT_FLAGS, sizeof(pure_flags), &pure_flags))
 331                 goto nla_put_failure;
 332
 333         tcf_tm_dump(&t, &d->tcf_tm);
 334         if (nla_put_64bit(skb, TCA_SKBEDIT_TM, sizeof(t), &t, TCA_SKBEDIT_PAD))
 335                 goto nla_put_failure;
 336         spin_unlock_bh(&d->tcf_lock);
 337
 338         return skb->len;
 339
 340 nla_put_failure:
 341         spin_unlock_bh(&d->tcf_lock);
 342         nlmsg_trim(skb, b);
 343         return -1;
 344 }
 345
 346 static void tcf_skbedit_cleanup(struct tc_action *a)
 347 {
 348         struct tcf_skbedit *d = to_skbedit(a);
 349         struct tcf_skbedit_params *params;
 350
 351         params = rcu_dereference_protected(d->params, 1);
 352         if (params)
 353                 kfree_rcu(params, rcu);
 354 }
 355
 356 static size_t tcf_skbedit_get_fill_size(const struct tc_action *act)
 357 {
 358         return nla_total_size(sizeof(struct tc_skbedit))
 359                 + nla_total_size(sizeof(u32)) /* TCA_SKBEDIT_PRIORITY */
 360                 + nla_total_size(sizeof(u16)) /* TCA_SKBEDIT_QUEUE_MAPPING */
 361                 + nla_total_size(sizeof(u16)) /* TCA_SKBEDIT_QUEUE_MAPPING_MAX */
 362                 + nla_total_size(sizeof(u32)) /* TCA_SKBEDIT_MARK */
 363                 + nla_total_size(sizeof(u16)) /* TCA_SKBEDIT_PTYPE */
 364                 + nla_total_size(sizeof(u32)) /* TCA_SKBEDIT_MASK */
 365                 + nla_total_size_64bit(sizeof(u64)); /* TCA_SKBEDIT_FLAGS */
 366 }
 367
 368 static int tcf_skbedit_offload_act_setup(struct tc_action *act, void *entry_data,
 369                                          u32 *index_inc, bool bind,
 370                                          struct netlink_ext_ack *extack)
 371 {
 372         if (bind) {
 373                 struct flow_action_entry *entry = entry_data;
 374
 375                 if (is_tcf_skbedit_mark(act)) {
 376                         entry->id = FLOW_ACTION_MARK;
 377                         entry->mark = tcf_skbedit_mark(act);
 378                 } else if (is_tcf_skbedit_ptype(act)) {
 379                         entry->id = FLOW_ACTION_PTYPE;
 380                         entry->ptype = tcf_skbedit_ptype(act);
 381                 } else if (is_tcf_skbedit_priority(act)) {
 382                         entry->id = FLOW_ACTION_PRIORITY;
 383                         entry->priority = tcf_skbedit_priority(act);
 384                 } else if (is_tcf_skbedit_tx_queue_mapping(act)) {
 385                         NL_SET_ERR_MSG_MOD(extack, "Offload not supported when \"queue_mapping\" option is used on transmit side");
 386                         return -EOPNOTSUPP;
 387                 } else if (is_tcf_skbedit_rx_queue_mapping(act)) {
 388                         entry->id = FLOW_ACTION_RX_QUEUE_MAPPING;
 389                         entry->rx_queue = tcf_skbedit_rx_queue_mapping(act);
 390                 } else if (is_tcf_skbedit_inheritdsfield(act)) {
 391                         NL_SET_ERR_MSG_MOD(extack, "Offload not supported when \"inheritdsfield\" option is used");
 392                         return -EOPNOTSUPP;
 393                 } else {
 394                         NL_SET_ERR_MSG_MOD(extack, "Unsupported skbedit option offload");
 395                         return -EOPNOTSUPP;
 396                 }
 397                 *index_inc = 1;
 398         } else {
 399                 struct flow_offload_action *fl_action = entry_data;
 400
 401                 if (is_tcf_skbedit_mark(act))
 402                         fl_action->id = FLOW_ACTION_MARK;
 403                 else if (is_tcf_skbedit_ptype(act))
 404                         fl_action->id = FLOW_ACTION_PTYPE;
 405                 else if (is_tcf_skbedit_priority(act))
 406                         fl_action->id = FLOW_ACTION_PRIORITY;
 407                 else if (is_tcf_skbedit_rx_queue_mapping(act))
 408                         fl_action->id = FLOW_ACTION_RX_QUEUE_MAPPING;
 409                 else
 410                         return -EOPNOTSUPP;
 411         }
 412
 413         return 0;
 414 }
 415
 416 static struct tc_action_ops act_skbedit_ops = {
 417         .kind           =       "skbedit",
 418         .id             =       TCA_ID_SKBEDIT,
 419         .owner          =       THIS_MODULE,
 420         .act            =       tcf_skbedit_act,
 421         .stats_update   =       tcf_skbedit_stats_update,
 422         .dump           =       tcf_skbedit_dump,
 423         .init           =       tcf_skbedit_init,
 424         .cleanup        =       tcf_skbedit_cleanup,
 425         .get_fill_size  =       tcf_skbedit_get_fill_size,
 426         .offload_act_setup =    tcf_skbedit_offload_act_setup,
 427         .size           =       sizeof(struct tcf_skbedit),
 428 };
 429
 430 static __net_init int skbedit_init_net(struct net *net)
 431 {
 432         struct tc_action_net *tn = net_generic(net, act_skbedit_ops.net_id);
 433
 434         return tc_action_net_init(net, tn, &act_skbedit_ops);
 435 }
 436
 437 static void __net_exit skbedit_exit_net(struct list_head *net_list)
 438 {
 439         tc_action_net_exit(net_list, act_skbedit_ops.net_id);
 440 }
 441
 442 static struct pernet_operations skbedit_net_ops = {
 443         .init = skbedit_init_net,
 444         .exit_batch = skbedit_exit_net,
 445         .id   = &act_skbedit_ops.net_id,
 446         .size = sizeof(struct tc_action_net),
 447 };
 448
 449 MODULE_AUTHOR("Alexander Duyck, <alexander.h.duyck@intel.com>");
 450 MODULE_DESCRIPTION("SKB Editing");
 451 MODULE_LICENSE("GPL");
 452
 453 static int __init skbedit_init_module(void)
 454 {
 455         return tcf_register_action(&act_skbedit_ops, &skbedit_net_ops);
 456 }
 457
 458 static void __exit skbedit_cleanup_module(void)
 459 {
 460         tcf_unregister_action(&act_skbedit_ops, &skbedit_net_ops);
 461 }
 462
 463 module_init(skbedit_init_module);
 464 module_exit(skbedit_cleanup_module);