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 20 #include <linux/tc_act/tc_skbedit.h> 21 #include <net/tc_act/tc_skbedit.h> 22 23 static unsigned int skbedit_net_id; 24 static struct tc_action_ops act_skbedit_ops; 25 26 static int tcf_skbedit_act(struct sk_buff *skb, const struct tc_action *a, 27 struct tcf_result *res) 28 { 29 struct tcf_skbedit *d = to_skbedit(a); 30 struct tcf_skbedit_params *params; 31 int action; 32 33 tcf_lastuse_update(&d->tcf_tm); 34 bstats_cpu_update(this_cpu_ptr(d->common.cpu_bstats), skb); 35 36 params = rcu_dereference_bh(d->params); 37 action = READ_ONCE(d->tcf_action); 38 39 if (params->flags & SKBEDIT_F_PRIORITY) 40 skb->priority = params->priority; 41 if (params->flags & SKBEDIT_F_INHERITDSFIELD) { 42 int wlen = skb_network_offset(skb); 43 44 switch (tc_skb_protocol(skb)) { 45 case htons(ETH_P_IP): 46 wlen += sizeof(struct iphdr); 47 if (!pskb_may_pull(skb, wlen)) 48 goto err; 49 skb->priority = ipv4_get_dsfield(ip_hdr(skb)) >> 2; 50 break; 51 52 case htons(ETH_P_IPV6): 53 wlen += sizeof(struct ipv6hdr); 54 if (!pskb_may_pull(skb, wlen)) 55 goto err; 56 skb->priority = ipv6_get_dsfield(ipv6_hdr(skb)) >> 2; 57 break; 58 } 59 } 60 if (params->flags & SKBEDIT_F_QUEUE_MAPPING && 61 skb->dev->real_num_tx_queues > params->queue_mapping) 62 skb_set_queue_mapping(skb, params->queue_mapping); 63 if (params->flags & SKBEDIT_F_MARK) { 64 skb->mark &= ~params->mask; 65 skb->mark |= params->mark & params->mask; 66 } 67 if (params->flags & SKBEDIT_F_PTYPE) 68 skb->pkt_type = params->ptype; 69 return action; 70 71 err: 72 qstats_drop_inc(this_cpu_ptr(d->common.cpu_qstats)); 73 return TC_ACT_SHOT; 74 } 75 76 static void tcf_skbedit_stats_update(struct tc_action *a, u64 bytes, 77 u64 packets, u64 drops, 78 u64 lastuse, bool hw) 79 { 80 struct tcf_skbedit *d = to_skbedit(a); 81 struct tcf_t *tm = &d->tcf_tm; 82 83 tcf_action_update_stats(a, bytes, packets, drops, hw); 84 tm->lastuse = max_t(u64, tm->lastuse, lastuse); 85 } 86 87 static const struct nla_policy skbedit_policy[TCA_SKBEDIT_MAX + 1] = { 88 [TCA_SKBEDIT_PARMS] = { .len = sizeof(struct tc_skbedit) }, 89 [TCA_SKBEDIT_PRIORITY] = { .len = sizeof(u32) }, 90 [TCA_SKBEDIT_QUEUE_MAPPING] = { .len = sizeof(u16) }, 91 [TCA_SKBEDIT_MARK] = { .len = sizeof(u32) }, 92 [TCA_SKBEDIT_PTYPE] = { .len = sizeof(u16) }, 93 [TCA_SKBEDIT_MASK] = { .len = sizeof(u32) }, 94 [TCA_SKBEDIT_FLAGS] = { .len = sizeof(u64) }, 95 }; 96 97 static int tcf_skbedit_init(struct net *net, struct nlattr *nla, 98 struct nlattr *est, struct tc_action **a, 99 int ovr, int bind, bool rtnl_held, 100 struct tcf_proto *tp, u32 act_flags, 101 struct netlink_ext_ack *extack) 102 { 103 struct tc_action_net *tn = net_generic(net, skbedit_net_id); 104 struct tcf_skbedit_params *params_new; 105 struct nlattr *tb[TCA_SKBEDIT_MAX + 1]; 106 struct tcf_chain *goto_ch = NULL; 107 struct tc_skbedit *parm; 108 struct tcf_skbedit *d; 109 u32 flags = 0, *priority = NULL, *mark = NULL, *mask = NULL; 110 u16 *queue_mapping = NULL, *ptype = NULL; 111 bool exists = false; 112 int ret = 0, err; 113 u32 index; 114 115 if (nla == NULL) 116 return -EINVAL; 117 118 err = nla_parse_nested_deprecated(tb, TCA_SKBEDIT_MAX, nla, 119 skbedit_policy, NULL); 120 if (err < 0) 121 return err; 122 123 if (tb[TCA_SKBEDIT_PARMS] == NULL) 124 return -EINVAL; 125 126 if (tb[TCA_SKBEDIT_PRIORITY] != NULL) { 127 flags |= SKBEDIT_F_PRIORITY; 128 priority = nla_data(tb[TCA_SKBEDIT_PRIORITY]); 129 } 130 131 if (tb[TCA_SKBEDIT_QUEUE_MAPPING] != NULL) { 132 flags |= SKBEDIT_F_QUEUE_MAPPING; 133 queue_mapping = nla_data(tb[TCA_SKBEDIT_QUEUE_MAPPING]); 134 } 135 136 if (tb[TCA_SKBEDIT_PTYPE] != NULL) { 137 ptype = nla_data(tb[TCA_SKBEDIT_PTYPE]); 138 if (!skb_pkt_type_ok(*ptype)) 139 return -EINVAL; 140 flags |= SKBEDIT_F_PTYPE; 141 } 142 143 if (tb[TCA_SKBEDIT_MARK] != NULL) { 144 flags |= SKBEDIT_F_MARK; 145 mark = nla_data(tb[TCA_SKBEDIT_MARK]); 146 } 147 148 if (tb[TCA_SKBEDIT_MASK] != NULL) { 149 flags |= SKBEDIT_F_MASK; 150 mask = nla_data(tb[TCA_SKBEDIT_MASK]); 151 } 152 153 if (tb[TCA_SKBEDIT_FLAGS] != NULL) { 154 u64 *pure_flags = nla_data(tb[TCA_SKBEDIT_FLAGS]); 155 156 if (*pure_flags & SKBEDIT_F_INHERITDSFIELD) 157 flags |= SKBEDIT_F_INHERITDSFIELD; 158 } 159 160 parm = nla_data(tb[TCA_SKBEDIT_PARMS]); 161 index = parm->index; 162 err = tcf_idr_check_alloc(tn, &index, a, bind); 163 if (err < 0) 164 return err; 165 exists = err; 166 if (exists && bind) 167 return 0; 168 169 if (!flags) { 170 if (exists) 171 tcf_idr_release(*a, bind); 172 else 173 tcf_idr_cleanup(tn, index); 174 return -EINVAL; 175 } 176 177 if (!exists) { 178 ret = tcf_idr_create(tn, index, est, a, 179 &act_skbedit_ops, bind, true, 0); 180 if (ret) { 181 tcf_idr_cleanup(tn, index); 182 return ret; 183 } 184 185 d = to_skbedit(*a); 186 ret = ACT_P_CREATED; 187 } else { 188 d = to_skbedit(*a); 189 if (!ovr) { 190 tcf_idr_release(*a, bind); 191 return -EEXIST; 192 } 193 } 194 err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack); 195 if (err < 0) 196 goto release_idr; 197 198 params_new = kzalloc(sizeof(*params_new), GFP_KERNEL); 199 if (unlikely(!params_new)) { 200 err = -ENOMEM; 201 goto put_chain; 202 } 203 204 params_new->flags = flags; 205 if (flags & SKBEDIT_F_PRIORITY) 206 params_new->priority = *priority; 207 if (flags & SKBEDIT_F_QUEUE_MAPPING) 208 params_new->queue_mapping = *queue_mapping; 209 if (flags & SKBEDIT_F_MARK) 210 params_new->mark = *mark; 211 if (flags & SKBEDIT_F_PTYPE) 212 params_new->ptype = *ptype; 213 /* default behaviour is to use all the bits */ 214 params_new->mask = 0xffffffff; 215 if (flags & SKBEDIT_F_MASK) 216 params_new->mask = *mask; 217 218 spin_lock_bh(&d->tcf_lock); 219 goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch); 220 params_new = rcu_replace_pointer(d->params, params_new, 221 lockdep_is_held(&d->tcf_lock)); 222 spin_unlock_bh(&d->tcf_lock); 223 if (params_new) 224 kfree_rcu(params_new, rcu); 225 if (goto_ch) 226 tcf_chain_put_by_act(goto_ch); 227 228 if (ret == ACT_P_CREATED) 229 tcf_idr_insert(tn, *a); 230 return ret; 231 put_chain: 232 if (goto_ch) 233 tcf_chain_put_by_act(goto_ch); 234 release_idr: 235 tcf_idr_release(*a, bind); 236 return err; 237 } 238 239 static int tcf_skbedit_dump(struct sk_buff *skb, struct tc_action *a, 240 int bind, int ref) 241 { 242 unsigned char *b = skb_tail_pointer(skb); 243 struct tcf_skbedit *d = to_skbedit(a); 244 struct tcf_skbedit_params *params; 245 struct tc_skbedit opt = { 246 .index = d->tcf_index, 247 .refcnt = refcount_read(&d->tcf_refcnt) - ref, 248 .bindcnt = atomic_read(&d->tcf_bindcnt) - bind, 249 }; 250 u64 pure_flags = 0; 251 struct tcf_t t; 252 253 spin_lock_bh(&d->tcf_lock); 254 params = rcu_dereference_protected(d->params, 255 lockdep_is_held(&d->tcf_lock)); 256 opt.action = d->tcf_action; 257 258 if (nla_put(skb, TCA_SKBEDIT_PARMS, sizeof(opt), &opt)) 259 goto nla_put_failure; 260 if ((params->flags & SKBEDIT_F_PRIORITY) && 261 nla_put_u32(skb, TCA_SKBEDIT_PRIORITY, params->priority)) 262 goto nla_put_failure; 263 if ((params->flags & SKBEDIT_F_QUEUE_MAPPING) && 264 nla_put_u16(skb, TCA_SKBEDIT_QUEUE_MAPPING, params->queue_mapping)) 265 goto nla_put_failure; 266 if ((params->flags & SKBEDIT_F_MARK) && 267 nla_put_u32(skb, TCA_SKBEDIT_MARK, params->mark)) 268 goto nla_put_failure; 269 if ((params->flags & SKBEDIT_F_PTYPE) && 270 nla_put_u16(skb, TCA_SKBEDIT_PTYPE, params->ptype)) 271 goto nla_put_failure; 272 if ((params->flags & SKBEDIT_F_MASK) && 273 nla_put_u32(skb, TCA_SKBEDIT_MASK, params->mask)) 274 goto nla_put_failure; 275 if (params->flags & SKBEDIT_F_INHERITDSFIELD) 276 pure_flags |= SKBEDIT_F_INHERITDSFIELD; 277 if (pure_flags != 0 && 278 nla_put(skb, TCA_SKBEDIT_FLAGS, sizeof(pure_flags), &pure_flags)) 279 goto nla_put_failure; 280 281 tcf_tm_dump(&t, &d->tcf_tm); 282 if (nla_put_64bit(skb, TCA_SKBEDIT_TM, sizeof(t), &t, TCA_SKBEDIT_PAD)) 283 goto nla_put_failure; 284 spin_unlock_bh(&d->tcf_lock); 285 286 return skb->len; 287 288 nla_put_failure: 289 spin_unlock_bh(&d->tcf_lock); 290 nlmsg_trim(skb, b); 291 return -1; 292 } 293 294 static void tcf_skbedit_cleanup(struct tc_action *a) 295 { 296 struct tcf_skbedit *d = to_skbedit(a); 297 struct tcf_skbedit_params *params; 298 299 params = rcu_dereference_protected(d->params, 1); 300 if (params) 301 kfree_rcu(params, rcu); 302 } 303 304 static int tcf_skbedit_walker(struct net *net, struct sk_buff *skb, 305 struct netlink_callback *cb, int type, 306 const struct tc_action_ops *ops, 307 struct netlink_ext_ack *extack) 308 { 309 struct tc_action_net *tn = net_generic(net, skbedit_net_id); 310 311 return tcf_generic_walker(tn, skb, cb, type, ops, extack); 312 } 313 314 static int tcf_skbedit_search(struct net *net, struct tc_action **a, u32 index) 315 { 316 struct tc_action_net *tn = net_generic(net, skbedit_net_id); 317 318 return tcf_idr_search(tn, a, index); 319 } 320 321 static size_t tcf_skbedit_get_fill_size(const struct tc_action *act) 322 { 323 return nla_total_size(sizeof(struct tc_skbedit)) 324 + nla_total_size(sizeof(u32)) /* TCA_SKBEDIT_PRIORITY */ 325 + nla_total_size(sizeof(u16)) /* TCA_SKBEDIT_QUEUE_MAPPING */ 326 + nla_total_size(sizeof(u32)) /* TCA_SKBEDIT_MARK */ 327 + nla_total_size(sizeof(u16)) /* TCA_SKBEDIT_PTYPE */ 328 + nla_total_size(sizeof(u32)) /* TCA_SKBEDIT_MASK */ 329 + nla_total_size_64bit(sizeof(u64)); /* TCA_SKBEDIT_FLAGS */ 330 } 331 332 static struct tc_action_ops act_skbedit_ops = { 333 .kind = "skbedit", 334 .id = TCA_ID_SKBEDIT, 335 .owner = THIS_MODULE, 336 .act = tcf_skbedit_act, 337 .stats_update = tcf_skbedit_stats_update, 338 .dump = tcf_skbedit_dump, 339 .init = tcf_skbedit_init, 340 .cleanup = tcf_skbedit_cleanup, 341 .walk = tcf_skbedit_walker, 342 .get_fill_size = tcf_skbedit_get_fill_size, 343 .lookup = tcf_skbedit_search, 344 .size = sizeof(struct tcf_skbedit), 345 }; 346 347 static __net_init int skbedit_init_net(struct net *net) 348 { 349 struct tc_action_net *tn = net_generic(net, skbedit_net_id); 350 351 return tc_action_net_init(net, tn, &act_skbedit_ops); 352 } 353 354 static void __net_exit skbedit_exit_net(struct list_head *net_list) 355 { 356 tc_action_net_exit(net_list, skbedit_net_id); 357 } 358 359 static struct pernet_operations skbedit_net_ops = { 360 .init = skbedit_init_net, 361 .exit_batch = skbedit_exit_net, 362 .id = &skbedit_net_id, 363 .size = sizeof(struct tc_action_net), 364 }; 365 366 MODULE_AUTHOR("Alexander Duyck, <alexander.h.duyck@intel.com>"); 367 MODULE_DESCRIPTION("SKB Editing"); 368 MODULE_LICENSE("GPL"); 369 370 static int __init skbedit_init_module(void) 371 { 372 return tcf_register_action(&act_skbedit_ops, &skbedit_net_ops); 373 } 374 375 static void __exit skbedit_cleanup_module(void) 376 { 377 tcf_unregister_action(&act_skbedit_ops, &skbedit_net_ops); 378 } 379 380 module_init(skbedit_init_module); 381 module_exit(skbedit_cleanup_module); 382