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, struct netlink_ext_ack *extack) 113 { 114 struct tc_action_net *tn = net_generic(net, vlan_net_id); 115 struct nlattr *tb[TCA_VLAN_MAX + 1]; 116 struct tcf_vlan_params *p, *p_old; 117 struct tc_vlan *parm; 118 struct tcf_vlan *v; 119 int action; 120 u16 push_vid = 0; 121 __be16 push_proto = 0; 122 u8 push_prio = 0; 123 bool exists = false; 124 int ret = 0, err; 125 126 if (!nla) 127 return -EINVAL; 128 129 err = nla_parse_nested(tb, TCA_VLAN_MAX, nla, vlan_policy, NULL); 130 if (err < 0) 131 return err; 132 133 if (!tb[TCA_VLAN_PARMS]) 134 return -EINVAL; 135 parm = nla_data(tb[TCA_VLAN_PARMS]); 136 exists = tcf_idr_check(tn, parm->index, a, bind); 137 if (exists && bind) 138 return 0; 139 140 switch (parm->v_action) { 141 case TCA_VLAN_ACT_POP: 142 break; 143 case TCA_VLAN_ACT_PUSH: 144 case TCA_VLAN_ACT_MODIFY: 145 if (!tb[TCA_VLAN_PUSH_VLAN_ID]) { 146 if (exists) 147 tcf_idr_release(*a, bind); 148 return -EINVAL; 149 } 150 push_vid = nla_get_u16(tb[TCA_VLAN_PUSH_VLAN_ID]); 151 if (push_vid >= VLAN_VID_MASK) { 152 if (exists) 153 tcf_idr_release(*a, bind); 154 return -ERANGE; 155 } 156 157 if (tb[TCA_VLAN_PUSH_VLAN_PROTOCOL]) { 158 push_proto = nla_get_be16(tb[TCA_VLAN_PUSH_VLAN_PROTOCOL]); 159 switch (push_proto) { 160 case htons(ETH_P_8021Q): 161 case htons(ETH_P_8021AD): 162 break; 163 default: 164 return -EPROTONOSUPPORT; 165 } 166 } else { 167 push_proto = htons(ETH_P_8021Q); 168 } 169 170 if (tb[TCA_VLAN_PUSH_VLAN_PRIORITY]) 171 push_prio = nla_get_u8(tb[TCA_VLAN_PUSH_VLAN_PRIORITY]); 172 break; 173 default: 174 if (exists) 175 tcf_idr_release(*a, bind); 176 return -EINVAL; 177 } 178 action = parm->v_action; 179 180 if (!exists) { 181 ret = tcf_idr_create(tn, parm->index, est, a, 182 &act_vlan_ops, bind, true); 183 if (ret) 184 return ret; 185 186 ret = ACT_P_CREATED; 187 } else { 188 tcf_idr_release(*a, bind); 189 if (!ovr) 190 return -EEXIST; 191 } 192 193 v = to_vlan(*a); 194 195 ASSERT_RTNL(); 196 p = kzalloc(sizeof(*p), GFP_KERNEL); 197 if (!p) { 198 if (ret == ACT_P_CREATED) 199 tcf_idr_release(*a, bind); 200 return -ENOMEM; 201 } 202 203 v->tcf_action = parm->action; 204 205 p_old = rtnl_dereference(v->vlan_p); 206 207 p->tcfv_action = action; 208 p->tcfv_push_vid = push_vid; 209 p->tcfv_push_prio = push_prio; 210 p->tcfv_push_proto = push_proto; 211 212 rcu_assign_pointer(v->vlan_p, p); 213 214 if (p_old) 215 kfree_rcu(p_old, rcu); 216 217 if (ret == ACT_P_CREATED) 218 tcf_idr_insert(tn, *a); 219 return ret; 220 } 221 222 static void tcf_vlan_cleanup(struct tc_action *a) 223 { 224 struct tcf_vlan *v = to_vlan(a); 225 struct tcf_vlan_params *p; 226 227 p = rcu_dereference_protected(v->vlan_p, 1); 228 if (p) 229 kfree_rcu(p, rcu); 230 } 231 232 static int tcf_vlan_dump(struct sk_buff *skb, struct tc_action *a, 233 int bind, int ref) 234 { 235 unsigned char *b = skb_tail_pointer(skb); 236 struct tcf_vlan *v = to_vlan(a); 237 struct tcf_vlan_params *p = rtnl_dereference(v->vlan_p); 238 struct tc_vlan opt = { 239 .index = v->tcf_index, 240 .refcnt = v->tcf_refcnt - ref, 241 .bindcnt = v->tcf_bindcnt - bind, 242 .action = v->tcf_action, 243 .v_action = p->tcfv_action, 244 }; 245 struct tcf_t t; 246 247 if (nla_put(skb, TCA_VLAN_PARMS, sizeof(opt), &opt)) 248 goto nla_put_failure; 249 250 if ((p->tcfv_action == TCA_VLAN_ACT_PUSH || 251 p->tcfv_action == TCA_VLAN_ACT_MODIFY) && 252 (nla_put_u16(skb, TCA_VLAN_PUSH_VLAN_ID, p->tcfv_push_vid) || 253 nla_put_be16(skb, TCA_VLAN_PUSH_VLAN_PROTOCOL, 254 p->tcfv_push_proto) || 255 (nla_put_u8(skb, TCA_VLAN_PUSH_VLAN_PRIORITY, 256 p->tcfv_push_prio)))) 257 goto nla_put_failure; 258 259 tcf_tm_dump(&t, &v->tcf_tm); 260 if (nla_put_64bit(skb, TCA_VLAN_TM, sizeof(t), &t, TCA_VLAN_PAD)) 261 goto nla_put_failure; 262 return skb->len; 263 264 nla_put_failure: 265 nlmsg_trim(skb, b); 266 return -1; 267 } 268 269 static int tcf_vlan_walker(struct net *net, struct sk_buff *skb, 270 struct netlink_callback *cb, int type, 271 const struct tc_action_ops *ops, 272 struct netlink_ext_ack *extack) 273 { 274 struct tc_action_net *tn = net_generic(net, vlan_net_id); 275 276 return tcf_generic_walker(tn, skb, cb, type, ops, extack); 277 } 278 279 static int tcf_vlan_search(struct net *net, struct tc_action **a, u32 index, 280 struct netlink_ext_ack *extack) 281 { 282 struct tc_action_net *tn = net_generic(net, vlan_net_id); 283 284 return tcf_idr_search(tn, a, index); 285 } 286 287 static struct tc_action_ops act_vlan_ops = { 288 .kind = "vlan", 289 .type = TCA_ACT_VLAN, 290 .owner = THIS_MODULE, 291 .act = tcf_vlan, 292 .dump = tcf_vlan_dump, 293 .init = tcf_vlan_init, 294 .cleanup = tcf_vlan_cleanup, 295 .walk = tcf_vlan_walker, 296 .lookup = tcf_vlan_search, 297 .size = sizeof(struct tcf_vlan), 298 }; 299 300 static __net_init int vlan_init_net(struct net *net) 301 { 302 struct tc_action_net *tn = net_generic(net, vlan_net_id); 303 304 return tc_action_net_init(tn, &act_vlan_ops); 305 } 306 307 static void __net_exit vlan_exit_net(struct list_head *net_list) 308 { 309 tc_action_net_exit(net_list, vlan_net_id); 310 } 311 312 static struct pernet_operations vlan_net_ops = { 313 .init = vlan_init_net, 314 .exit_batch = vlan_exit_net, 315 .id = &vlan_net_id, 316 .size = sizeof(struct tc_action_net), 317 }; 318 319 static int __init vlan_init_module(void) 320 { 321 return tcf_register_action(&act_vlan_ops, &vlan_net_ops); 322 } 323 324 static void __exit vlan_cleanup_module(void) 325 { 326 tcf_unregister_action(&act_vlan_ops, &vlan_net_ops); 327 } 328 329 module_init(vlan_init_module); 330 module_exit(vlan_cleanup_module); 331 332 MODULE_AUTHOR("Jiri Pirko <jiri@resnulli.us>"); 333 MODULE_DESCRIPTION("vlan manipulation actions"); 334 MODULE_LICENSE("GPL v2"); 335