1 /* 2 * Copyright (c) 2008, Intel Corporation. 3 * 4 * This program is free software; you can redistribute it and/or modify it 5 * under the terms and conditions of the GNU General Public License, 6 * version 2, as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope it will be useful, but WITHOUT 9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 11 * more details. 12 * 13 * You should have received a copy of the GNU General Public License along with 14 * this program; if not, see <http://www.gnu.org/licenses/>. 15 * 16 * Author: Alexander Duyck <alexander.h.duyck@intel.com> 17 */ 18 19 #include <linux/module.h> 20 #include <linux/init.h> 21 #include <linux/kernel.h> 22 #include <linux/skbuff.h> 23 #include <linux/rtnetlink.h> 24 #include <net/netlink.h> 25 #include <net/pkt_sched.h> 26 #include <net/ip.h> 27 #include <net/ipv6.h> 28 #include <net/dsfield.h> 29 30 #include <linux/tc_act/tc_skbedit.h> 31 #include <net/tc_act/tc_skbedit.h> 32 33 static unsigned int skbedit_net_id; 34 static struct tc_action_ops act_skbedit_ops; 35 36 static int tcf_skbedit(struct sk_buff *skb, const struct tc_action *a, 37 struct tcf_result *res) 38 { 39 struct tcf_skbedit *d = to_skbedit(a); 40 41 spin_lock(&d->tcf_lock); 42 tcf_lastuse_update(&d->tcf_tm); 43 bstats_update(&d->tcf_bstats, skb); 44 45 if (d->flags & SKBEDIT_F_PRIORITY) 46 skb->priority = d->priority; 47 if (d->flags & SKBEDIT_F_INHERITDSFIELD) { 48 int wlen = skb_network_offset(skb); 49 50 switch (tc_skb_protocol(skb)) { 51 case htons(ETH_P_IP): 52 wlen += sizeof(struct iphdr); 53 if (!pskb_may_pull(skb, wlen)) 54 goto err; 55 skb->priority = ipv4_get_dsfield(ip_hdr(skb)) >> 2; 56 break; 57 58 case htons(ETH_P_IPV6): 59 wlen += sizeof(struct ipv6hdr); 60 if (!pskb_may_pull(skb, wlen)) 61 goto err; 62 skb->priority = ipv6_get_dsfield(ipv6_hdr(skb)) >> 2; 63 break; 64 } 65 } 66 if (d->flags & SKBEDIT_F_QUEUE_MAPPING && 67 skb->dev->real_num_tx_queues > d->queue_mapping) 68 skb_set_queue_mapping(skb, d->queue_mapping); 69 if (d->flags & SKBEDIT_F_MARK) { 70 skb->mark &= ~d->mask; 71 skb->mark |= d->mark & d->mask; 72 } 73 if (d->flags & SKBEDIT_F_PTYPE) 74 skb->pkt_type = d->ptype; 75 76 spin_unlock(&d->tcf_lock); 77 return d->tcf_action; 78 79 err: 80 d->tcf_qstats.drops++; 81 spin_unlock(&d->tcf_lock); 82 return TC_ACT_SHOT; 83 } 84 85 static const struct nla_policy skbedit_policy[TCA_SKBEDIT_MAX + 1] = { 86 [TCA_SKBEDIT_PARMS] = { .len = sizeof(struct tc_skbedit) }, 87 [TCA_SKBEDIT_PRIORITY] = { .len = sizeof(u32) }, 88 [TCA_SKBEDIT_QUEUE_MAPPING] = { .len = sizeof(u16) }, 89 [TCA_SKBEDIT_MARK] = { .len = sizeof(u32) }, 90 [TCA_SKBEDIT_PTYPE] = { .len = sizeof(u16) }, 91 [TCA_SKBEDIT_MASK] = { .len = sizeof(u32) }, 92 [TCA_SKBEDIT_FLAGS] = { .len = sizeof(u64) }, 93 }; 94 95 static int tcf_skbedit_init(struct net *net, struct nlattr *nla, 96 struct nlattr *est, struct tc_action **a, 97 int ovr, int bind, bool rtnl_held, 98 struct netlink_ext_ack *extack) 99 { 100 struct tc_action_net *tn = net_generic(net, skbedit_net_id); 101 struct nlattr *tb[TCA_SKBEDIT_MAX + 1]; 102 struct tc_skbedit *parm; 103 struct tcf_skbedit *d; 104 u32 flags = 0, *priority = NULL, *mark = NULL, *mask = NULL; 105 u16 *queue_mapping = NULL, *ptype = NULL; 106 bool exists = false; 107 int ret = 0, err; 108 109 if (nla == NULL) 110 return -EINVAL; 111 112 err = nla_parse_nested(tb, TCA_SKBEDIT_MAX, nla, skbedit_policy, NULL); 113 if (err < 0) 114 return err; 115 116 if (tb[TCA_SKBEDIT_PARMS] == NULL) 117 return -EINVAL; 118 119 if (tb[TCA_SKBEDIT_PRIORITY] != NULL) { 120 flags |= SKBEDIT_F_PRIORITY; 121 priority = nla_data(tb[TCA_SKBEDIT_PRIORITY]); 122 } 123 124 if (tb[TCA_SKBEDIT_QUEUE_MAPPING] != NULL) { 125 flags |= SKBEDIT_F_QUEUE_MAPPING; 126 queue_mapping = nla_data(tb[TCA_SKBEDIT_QUEUE_MAPPING]); 127 } 128 129 if (tb[TCA_SKBEDIT_PTYPE] != NULL) { 130 ptype = nla_data(tb[TCA_SKBEDIT_PTYPE]); 131 if (!skb_pkt_type_ok(*ptype)) 132 return -EINVAL; 133 flags |= SKBEDIT_F_PTYPE; 134 } 135 136 if (tb[TCA_SKBEDIT_MARK] != NULL) { 137 flags |= SKBEDIT_F_MARK; 138 mark = nla_data(tb[TCA_SKBEDIT_MARK]); 139 } 140 141 if (tb[TCA_SKBEDIT_MASK] != NULL) { 142 flags |= SKBEDIT_F_MASK; 143 mask = nla_data(tb[TCA_SKBEDIT_MASK]); 144 } 145 146 if (tb[TCA_SKBEDIT_FLAGS] != NULL) { 147 u64 *pure_flags = nla_data(tb[TCA_SKBEDIT_FLAGS]); 148 149 if (*pure_flags & SKBEDIT_F_INHERITDSFIELD) 150 flags |= SKBEDIT_F_INHERITDSFIELD; 151 } 152 153 parm = nla_data(tb[TCA_SKBEDIT_PARMS]); 154 155 exists = tcf_idr_check(tn, parm->index, a, bind); 156 if (exists && bind) 157 return 0; 158 159 if (!flags) { 160 if (exists) 161 tcf_idr_release(*a, bind); 162 return -EINVAL; 163 } 164 165 if (!exists) { 166 ret = tcf_idr_create(tn, parm->index, est, a, 167 &act_skbedit_ops, bind, false); 168 if (ret) 169 return ret; 170 171 d = to_skbedit(*a); 172 ret = ACT_P_CREATED; 173 } else { 174 d = to_skbedit(*a); 175 if (!ovr) { 176 tcf_idr_release(*a, bind); 177 return -EEXIST; 178 } 179 } 180 181 spin_lock_bh(&d->tcf_lock); 182 183 d->flags = flags; 184 if (flags & SKBEDIT_F_PRIORITY) 185 d->priority = *priority; 186 if (flags & SKBEDIT_F_QUEUE_MAPPING) 187 d->queue_mapping = *queue_mapping; 188 if (flags & SKBEDIT_F_MARK) 189 d->mark = *mark; 190 if (flags & SKBEDIT_F_PTYPE) 191 d->ptype = *ptype; 192 /* default behaviour is to use all the bits */ 193 d->mask = 0xffffffff; 194 if (flags & SKBEDIT_F_MASK) 195 d->mask = *mask; 196 197 d->tcf_action = parm->action; 198 199 spin_unlock_bh(&d->tcf_lock); 200 201 if (ret == ACT_P_CREATED) 202 tcf_idr_insert(tn, *a); 203 return ret; 204 } 205 206 static int tcf_skbedit_dump(struct sk_buff *skb, struct tc_action *a, 207 int bind, int ref) 208 { 209 unsigned char *b = skb_tail_pointer(skb); 210 struct tcf_skbedit *d = to_skbedit(a); 211 struct tc_skbedit opt = { 212 .index = d->tcf_index, 213 .refcnt = refcount_read(&d->tcf_refcnt) - ref, 214 .bindcnt = atomic_read(&d->tcf_bindcnt) - bind, 215 .action = d->tcf_action, 216 }; 217 struct tcf_t t; 218 u64 pure_flags = 0; 219 220 if (nla_put(skb, TCA_SKBEDIT_PARMS, sizeof(opt), &opt)) 221 goto nla_put_failure; 222 if ((d->flags & SKBEDIT_F_PRIORITY) && 223 nla_put_u32(skb, TCA_SKBEDIT_PRIORITY, d->priority)) 224 goto nla_put_failure; 225 if ((d->flags & SKBEDIT_F_QUEUE_MAPPING) && 226 nla_put_u16(skb, TCA_SKBEDIT_QUEUE_MAPPING, d->queue_mapping)) 227 goto nla_put_failure; 228 if ((d->flags & SKBEDIT_F_MARK) && 229 nla_put_u32(skb, TCA_SKBEDIT_MARK, d->mark)) 230 goto nla_put_failure; 231 if ((d->flags & SKBEDIT_F_PTYPE) && 232 nla_put_u16(skb, TCA_SKBEDIT_PTYPE, d->ptype)) 233 goto nla_put_failure; 234 if ((d->flags & SKBEDIT_F_MASK) && 235 nla_put_u32(skb, TCA_SKBEDIT_MASK, d->mask)) 236 goto nla_put_failure; 237 if (d->flags & SKBEDIT_F_INHERITDSFIELD) 238 pure_flags |= SKBEDIT_F_INHERITDSFIELD; 239 if (pure_flags != 0 && 240 nla_put(skb, TCA_SKBEDIT_FLAGS, sizeof(pure_flags), &pure_flags)) 241 goto nla_put_failure; 242 243 tcf_tm_dump(&t, &d->tcf_tm); 244 if (nla_put_64bit(skb, TCA_SKBEDIT_TM, sizeof(t), &t, TCA_SKBEDIT_PAD)) 245 goto nla_put_failure; 246 return skb->len; 247 248 nla_put_failure: 249 nlmsg_trim(skb, b); 250 return -1; 251 } 252 253 static int tcf_skbedit_walker(struct net *net, struct sk_buff *skb, 254 struct netlink_callback *cb, int type, 255 const struct tc_action_ops *ops, 256 struct netlink_ext_ack *extack) 257 { 258 struct tc_action_net *tn = net_generic(net, skbedit_net_id); 259 260 return tcf_generic_walker(tn, skb, cb, type, ops, extack); 261 } 262 263 static int tcf_skbedit_search(struct net *net, struct tc_action **a, u32 index, 264 struct netlink_ext_ack *extack) 265 { 266 struct tc_action_net *tn = net_generic(net, skbedit_net_id); 267 268 return tcf_idr_search(tn, a, index); 269 } 270 271 static int tcf_skbedit_delete(struct net *net, u32 index) 272 { 273 struct tc_action_net *tn = net_generic(net, skbedit_net_id); 274 275 return tcf_idr_delete_index(tn, index); 276 } 277 278 static struct tc_action_ops act_skbedit_ops = { 279 .kind = "skbedit", 280 .type = TCA_ACT_SKBEDIT, 281 .owner = THIS_MODULE, 282 .act = tcf_skbedit, 283 .dump = tcf_skbedit_dump, 284 .init = tcf_skbedit_init, 285 .walk = tcf_skbedit_walker, 286 .lookup = tcf_skbedit_search, 287 .delete = tcf_skbedit_delete, 288 .size = sizeof(struct tcf_skbedit), 289 }; 290 291 static __net_init int skbedit_init_net(struct net *net) 292 { 293 struct tc_action_net *tn = net_generic(net, skbedit_net_id); 294 295 return tc_action_net_init(tn, &act_skbedit_ops); 296 } 297 298 static void __net_exit skbedit_exit_net(struct list_head *net_list) 299 { 300 tc_action_net_exit(net_list, skbedit_net_id); 301 } 302 303 static struct pernet_operations skbedit_net_ops = { 304 .init = skbedit_init_net, 305 .exit_batch = skbedit_exit_net, 306 .id = &skbedit_net_id, 307 .size = sizeof(struct tc_action_net), 308 }; 309 310 MODULE_AUTHOR("Alexander Duyck, <alexander.h.duyck@intel.com>"); 311 MODULE_DESCRIPTION("SKB Editing"); 312 MODULE_LICENSE("GPL"); 313 314 static int __init skbedit_init_module(void) 315 { 316 return tcf_register_action(&act_skbedit_ops, &skbedit_net_ops); 317 } 318 319 static void __exit skbedit_cleanup_module(void) 320 { 321 tcf_unregister_action(&act_skbedit_ops, &skbedit_net_ops); 322 } 323 324 module_init(skbedit_init_module); 325 module_exit(skbedit_cleanup_module); 326