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