1 /* 2 * Copyright (c) 2014 Jiri Pirko <jiri@resnulli.us> 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License as published by 6 * the Free Software Foundation; either version 2 of the License, or 7 * (at your option) any later version. 8 */ 9 10 #include <linux/module.h> 11 #include <linux/init.h> 12 #include <linux/kernel.h> 13 #include <linux/skbuff.h> 14 #include <linux/rtnetlink.h> 15 #include <linux/if_vlan.h> 16 #include <net/netlink.h> 17 #include <net/pkt_sched.h> 18 19 #include <linux/tc_act/tc_vlan.h> 20 #include <net/tc_act/tc_vlan.h> 21 22 static unsigned int vlan_net_id; 23 static struct tc_action_ops act_vlan_ops; 24 25 static int tcf_vlan(struct sk_buff *skb, const struct tc_action *a, 26 struct tcf_result *res) 27 { 28 struct tcf_vlan *v = to_vlan(a); 29 struct tcf_vlan_params *p; 30 int action; 31 int err; 32 u16 tci; 33 34 tcf_lastuse_update(&v->tcf_tm); 35 bstats_cpu_update(this_cpu_ptr(v->common.cpu_bstats), skb); 36 37 /* Ensure 'data' points at mac_header prior calling vlan manipulating 38 * functions. 39 */ 40 if (skb_at_tc_ingress(skb)) 41 skb_push_rcsum(skb, skb->mac_len); 42 43 rcu_read_lock(); 44 45 action = READ_ONCE(v->tcf_action); 46 47 p = rcu_dereference(v->vlan_p); 48 49 switch (p->tcfv_action) { 50 case TCA_VLAN_ACT_POP: 51 err = skb_vlan_pop(skb); 52 if (err) 53 goto drop; 54 break; 55 case TCA_VLAN_ACT_PUSH: 56 err = skb_vlan_push(skb, p->tcfv_push_proto, p->tcfv_push_vid | 57 (p->tcfv_push_prio << VLAN_PRIO_SHIFT)); 58 if (err) 59 goto drop; 60 break; 61 case TCA_VLAN_ACT_MODIFY: 62 /* No-op if no vlan tag (either hw-accel or in-payload) */ 63 if (!skb_vlan_tagged(skb)) 64 goto unlock; 65 /* extract existing tag (and guarantee no hw-accel tag) */ 66 if (skb_vlan_tag_present(skb)) { 67 tci = skb_vlan_tag_get(skb); 68 skb->vlan_tci = 0; 69 } else { 70 /* in-payload vlan tag, pop it */ 71 err = __skb_vlan_pop(skb, &tci); 72 if (err) 73 goto drop; 74 } 75 /* replace the vid */ 76 tci = (tci & ~VLAN_VID_MASK) | p->tcfv_push_vid; 77 /* replace prio bits, if tcfv_push_prio specified */ 78 if (p->tcfv_push_prio) { 79 tci &= ~VLAN_PRIO_MASK; 80 tci |= p->tcfv_push_prio << VLAN_PRIO_SHIFT; 81 } 82 /* put updated tci as hwaccel tag */ 83 __vlan_hwaccel_put_tag(skb, p->tcfv_push_proto, tci); 84 break; 85 default: 86 BUG(); 87 } 88 89 goto unlock; 90 91 drop: 92 action = TC_ACT_SHOT; 93 qstats_drop_inc(this_cpu_ptr(v->common.cpu_qstats)); 94 95 unlock: 96 rcu_read_unlock(); 97 if (skb_at_tc_ingress(skb)) 98 skb_pull_rcsum(skb, skb->mac_len); 99 100 return action; 101 } 102 103 static const struct nla_policy vlan_policy[TCA_VLAN_MAX + 1] = { 104 [TCA_VLAN_PARMS] = { .len = sizeof(struct tc_vlan) }, 105 [TCA_VLAN_PUSH_VLAN_ID] = { .type = NLA_U16 }, 106 [TCA_VLAN_PUSH_VLAN_PROTOCOL] = { .type = NLA_U16 }, 107 [TCA_VLAN_PUSH_VLAN_PRIORITY] = { .type = NLA_U8 }, 108 }; 109 110 static int tcf_vlan_init(struct net *net, struct nlattr *nla, 111 struct nlattr *est, struct tc_action **a, 112 int ovr, int bind, bool rtnl_held, 113 struct netlink_ext_ack *extack) 114 { 115 struct tc_action_net *tn = net_generic(net, vlan_net_id); 116 struct nlattr *tb[TCA_VLAN_MAX + 1]; 117 struct tcf_vlan_params *p, *p_old; 118 struct tc_vlan *parm; 119 struct tcf_vlan *v; 120 int action; 121 u16 push_vid = 0; 122 __be16 push_proto = 0; 123 u8 push_prio = 0; 124 bool exists = false; 125 int ret = 0, err; 126 127 if (!nla) 128 return -EINVAL; 129 130 err = nla_parse_nested(tb, TCA_VLAN_MAX, nla, vlan_policy, NULL); 131 if (err < 0) 132 return err; 133 134 if (!tb[TCA_VLAN_PARMS]) 135 return -EINVAL; 136 parm = nla_data(tb[TCA_VLAN_PARMS]); 137 exists = tcf_idr_check(tn, parm->index, a, bind); 138 if (exists && bind) 139 return 0; 140 141 switch (parm->v_action) { 142 case TCA_VLAN_ACT_POP: 143 break; 144 case TCA_VLAN_ACT_PUSH: 145 case TCA_VLAN_ACT_MODIFY: 146 if (!tb[TCA_VLAN_PUSH_VLAN_ID]) { 147 if (exists) 148 tcf_idr_release(*a, bind); 149 return -EINVAL; 150 } 151 push_vid = nla_get_u16(tb[TCA_VLAN_PUSH_VLAN_ID]); 152 if (push_vid >= VLAN_VID_MASK) { 153 if (exists) 154 tcf_idr_release(*a, bind); 155 return -ERANGE; 156 } 157 158 if (tb[TCA_VLAN_PUSH_VLAN_PROTOCOL]) { 159 push_proto = nla_get_be16(tb[TCA_VLAN_PUSH_VLAN_PROTOCOL]); 160 switch (push_proto) { 161 case htons(ETH_P_8021Q): 162 case htons(ETH_P_8021AD): 163 break; 164 default: 165 if (exists) 166 tcf_idr_release(*a, bind); 167 return -EPROTONOSUPPORT; 168 } 169 } else { 170 push_proto = htons(ETH_P_8021Q); 171 } 172 173 if (tb[TCA_VLAN_PUSH_VLAN_PRIORITY]) 174 push_prio = nla_get_u8(tb[TCA_VLAN_PUSH_VLAN_PRIORITY]); 175 break; 176 default: 177 if (exists) 178 tcf_idr_release(*a, bind); 179 return -EINVAL; 180 } 181 action = parm->v_action; 182 183 if (!exists) { 184 ret = tcf_idr_create(tn, parm->index, est, a, 185 &act_vlan_ops, bind, true); 186 if (ret) 187 return ret; 188 189 ret = ACT_P_CREATED; 190 } else if (!ovr) { 191 tcf_idr_release(*a, bind); 192 return -EEXIST; 193 } 194 195 v = to_vlan(*a); 196 197 ASSERT_RTNL(); 198 p = kzalloc(sizeof(*p), GFP_KERNEL); 199 if (!p) { 200 tcf_idr_release(*a, bind); 201 return -ENOMEM; 202 } 203 204 v->tcf_action = parm->action; 205 206 p_old = rtnl_dereference(v->vlan_p); 207 208 p->tcfv_action = action; 209 p->tcfv_push_vid = push_vid; 210 p->tcfv_push_prio = push_prio; 211 p->tcfv_push_proto = push_proto; 212 213 rcu_assign_pointer(v->vlan_p, p); 214 215 if (p_old) 216 kfree_rcu(p_old, rcu); 217 218 if (ret == ACT_P_CREATED) 219 tcf_idr_insert(tn, *a); 220 return ret; 221 } 222 223 static void tcf_vlan_cleanup(struct tc_action *a) 224 { 225 struct tcf_vlan *v = to_vlan(a); 226 struct tcf_vlan_params *p; 227 228 p = rcu_dereference_protected(v->vlan_p, 1); 229 if (p) 230 kfree_rcu(p, rcu); 231 } 232 233 static int tcf_vlan_dump(struct sk_buff *skb, struct tc_action *a, 234 int bind, int ref) 235 { 236 unsigned char *b = skb_tail_pointer(skb); 237 struct tcf_vlan *v = to_vlan(a); 238 struct tcf_vlan_params *p = rtnl_dereference(v->vlan_p); 239 struct tc_vlan opt = { 240 .index = v->tcf_index, 241 .refcnt = refcount_read(&v->tcf_refcnt) - ref, 242 .bindcnt = atomic_read(&v->tcf_bindcnt) - bind, 243 .action = v->tcf_action, 244 .v_action = p->tcfv_action, 245 }; 246 struct tcf_t t; 247 248 if (nla_put(skb, TCA_VLAN_PARMS, sizeof(opt), &opt)) 249 goto nla_put_failure; 250 251 if ((p->tcfv_action == TCA_VLAN_ACT_PUSH || 252 p->tcfv_action == TCA_VLAN_ACT_MODIFY) && 253 (nla_put_u16(skb, TCA_VLAN_PUSH_VLAN_ID, p->tcfv_push_vid) || 254 nla_put_be16(skb, TCA_VLAN_PUSH_VLAN_PROTOCOL, 255 p->tcfv_push_proto) || 256 (nla_put_u8(skb, TCA_VLAN_PUSH_VLAN_PRIORITY, 257 p->tcfv_push_prio)))) 258 goto nla_put_failure; 259 260 tcf_tm_dump(&t, &v->tcf_tm); 261 if (nla_put_64bit(skb, TCA_VLAN_TM, sizeof(t), &t, TCA_VLAN_PAD)) 262 goto nla_put_failure; 263 return skb->len; 264 265 nla_put_failure: 266 nlmsg_trim(skb, b); 267 return -1; 268 } 269 270 static int tcf_vlan_walker(struct net *net, struct sk_buff *skb, 271 struct netlink_callback *cb, int type, 272 const struct tc_action_ops *ops, 273 struct netlink_ext_ack *extack) 274 { 275 struct tc_action_net *tn = net_generic(net, vlan_net_id); 276 277 return tcf_generic_walker(tn, skb, cb, type, ops, extack); 278 } 279 280 static int tcf_vlan_search(struct net *net, struct tc_action **a, u32 index, 281 struct netlink_ext_ack *extack) 282 { 283 struct tc_action_net *tn = net_generic(net, vlan_net_id); 284 285 return tcf_idr_search(tn, a, index); 286 } 287 288 static int tcf_vlan_delete(struct net *net, u32 index) 289 { 290 struct tc_action_net *tn = net_generic(net, vlan_net_id); 291 292 return tcf_idr_delete_index(tn, index); 293 } 294 295 static struct tc_action_ops act_vlan_ops = { 296 .kind = "vlan", 297 .type = TCA_ACT_VLAN, 298 .owner = THIS_MODULE, 299 .act = tcf_vlan, 300 .dump = tcf_vlan_dump, 301 .init = tcf_vlan_init, 302 .cleanup = tcf_vlan_cleanup, 303 .walk = tcf_vlan_walker, 304 .lookup = tcf_vlan_search, 305 .delete = tcf_vlan_delete, 306 .size = sizeof(struct tcf_vlan), 307 }; 308 309 static __net_init int vlan_init_net(struct net *net) 310 { 311 struct tc_action_net *tn = net_generic(net, vlan_net_id); 312 313 return tc_action_net_init(tn, &act_vlan_ops); 314 } 315 316 static void __net_exit vlan_exit_net(struct list_head *net_list) 317 { 318 tc_action_net_exit(net_list, vlan_net_id); 319 } 320 321 static struct pernet_operations vlan_net_ops = { 322 .init = vlan_init_net, 323 .exit_batch = vlan_exit_net, 324 .id = &vlan_net_id, 325 .size = sizeof(struct tc_action_net), 326 }; 327 328 static int __init vlan_init_module(void) 329 { 330 return tcf_register_action(&act_vlan_ops, &vlan_net_ops); 331 } 332 333 static void __exit vlan_cleanup_module(void) 334 { 335 tcf_unregister_action(&act_vlan_ops, &vlan_net_ops); 336 } 337 338 module_init(vlan_init_module); 339 module_exit(vlan_cleanup_module); 340 341 MODULE_AUTHOR("Jiri Pirko <jiri@resnulli.us>"); 342 MODULE_DESCRIPTION("vlan manipulation actions"); 343 MODULE_LICENSE("GPL v2"); 344