Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 1 | /* |
| 2 | * net/sched/cls_cgroup.c Control Group Classifier |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or |
| 5 | * modify it under the terms of the GNU General Public License |
| 6 | * as published by the Free Software Foundation; either version |
| 7 | * 2 of the License, or (at your option) any later version. |
| 8 | * |
| 9 | * Authors: Thomas Graf <tgraf@suug.ch> |
| 10 | */ |
| 11 | |
| 12 | #include <linux/module.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 13 | #include <linux/slab.h> |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 14 | #include <linux/skbuff.h> |
Herbert Xu | f845172 | 2010-05-24 00:12:34 -0700 | [diff] [blame] | 15 | #include <linux/rcupdate.h> |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 16 | #include <net/rtnetlink.h> |
| 17 | #include <net/pkt_cls.h> |
Herbert Xu | f845172 | 2010-05-24 00:12:34 -0700 | [diff] [blame] | 18 | #include <net/sock.h> |
| 19 | #include <net/cls_cgroup.h> |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 20 | |
Eric Dumazet | cc7ec45 | 2011-01-19 19:26:56 +0000 | [diff] [blame] | 21 | struct cls_cgroup_head { |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 22 | u32 handle; |
| 23 | struct tcf_exts exts; |
| 24 | struct tcf_ematch_tree ematches; |
John Fastabend | 952313b | 2014-09-12 20:06:26 -0700 | [diff] [blame] | 25 | struct tcf_proto *tp; |
| 26 | struct rcu_head rcu; |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 27 | }; |
| 28 | |
Eric Dumazet | dc7f9f6 | 2011-07-05 23:25:42 +0000 | [diff] [blame] | 29 | static int cls_cgroup_classify(struct sk_buff *skb, const struct tcf_proto *tp, |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 30 | struct tcf_result *res) |
| 31 | { |
John Fastabend | 952313b | 2014-09-12 20:06:26 -0700 | [diff] [blame] | 32 | struct cls_cgroup_head *head = rcu_dereference_bh(tp->root); |
Paul Menage | e65fcfd | 2009-05-26 20:47:02 -0700 | [diff] [blame] | 33 | u32 classid; |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 34 | |
Herbert Xu | f845172 | 2010-05-24 00:12:34 -0700 | [diff] [blame] | 35 | classid = task_cls_state(current)->classid; |
Herbert Xu | f845172 | 2010-05-24 00:12:34 -0700 | [diff] [blame] | 36 | |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 37 | /* |
| 38 | * Due to the nature of the classifier it is required to ignore all |
| 39 | * packets originating from softirq context as accessing `current' |
| 40 | * would lead to false results. |
| 41 | * |
| 42 | * This test assumes that all callers of dev_queue_xmit() explicitely |
| 43 | * disable bh. Knowing this, it is possible to detect softirq based |
| 44 | * calls by looking at the number of nested bh disable calls because |
| 45 | * softirqs always disables bh. |
| 46 | */ |
Venkatesh Pallipadi | 75e1056 | 2010-10-04 17:03:16 -0700 | [diff] [blame] | 47 | if (in_serving_softirq()) { |
Herbert Xu | f845172 | 2010-05-24 00:12:34 -0700 | [diff] [blame] | 48 | /* If there is an sk_classid we'll use that. */ |
| 49 | if (!skb->sk) |
| 50 | return -1; |
| 51 | classid = skb->sk->sk_classid; |
| 52 | } |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 53 | |
Paul Menage | e65fcfd | 2009-05-26 20:47:02 -0700 | [diff] [blame] | 54 | if (!classid) |
| 55 | return -1; |
| 56 | |
| 57 | if (!tcf_em_tree_match(skb, &head->ematches, NULL)) |
| 58 | return -1; |
| 59 | |
| 60 | res->classid = classid; |
| 61 | res->class = 0; |
| 62 | return tcf_exts_exec(skb, &head->exts, res); |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 63 | } |
| 64 | |
| 65 | static unsigned long cls_cgroup_get(struct tcf_proto *tp, u32 handle) |
| 66 | { |
| 67 | return 0UL; |
| 68 | } |
| 69 | |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 70 | static int cls_cgroup_init(struct tcf_proto *tp) |
| 71 | { |
| 72 | return 0; |
| 73 | } |
| 74 | |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 75 | static const struct nla_policy cgroup_policy[TCA_CGROUP_MAX + 1] = { |
| 76 | [TCA_CGROUP_EMATCHES] = { .type = NLA_NESTED }, |
| 77 | }; |
| 78 | |
John Fastabend | 952313b | 2014-09-12 20:06:26 -0700 | [diff] [blame] | 79 | static void cls_cgroup_destroy_rcu(struct rcu_head *root) |
| 80 | { |
| 81 | struct cls_cgroup_head *head = container_of(root, |
| 82 | struct cls_cgroup_head, |
| 83 | rcu); |
| 84 | |
WANG Cong | 18d0264 | 2014-09-25 10:26:37 -0700 | [diff] [blame] | 85 | tcf_exts_destroy(&head->exts); |
John Fastabend | 82a470f | 2014-10-05 21:27:53 -0700 | [diff] [blame] | 86 | tcf_em_tree_destroy(&head->ematches); |
John Fastabend | 952313b | 2014-09-12 20:06:26 -0700 | [diff] [blame] | 87 | kfree(head); |
| 88 | } |
| 89 | |
Benjamin LaHaise | c1b5273 | 2013-01-14 05:15:39 +0000 | [diff] [blame] | 90 | static int cls_cgroup_change(struct net *net, struct sk_buff *in_skb, |
Eric W. Biederman | af4c664 | 2012-05-25 13:42:45 -0600 | [diff] [blame] | 91 | struct tcf_proto *tp, unsigned long base, |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 92 | u32 handle, struct nlattr **tca, |
Cong Wang | 2f7ef2f | 2014-04-25 13:54:06 -0700 | [diff] [blame] | 93 | unsigned long *arg, bool ovr) |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 94 | { |
Eric Dumazet | cc7ec45 | 2011-01-19 19:26:56 +0000 | [diff] [blame] | 95 | struct nlattr *tb[TCA_CGROUP_MAX + 1]; |
John Fastabend | 952313b | 2014-09-12 20:06:26 -0700 | [diff] [blame] | 96 | struct cls_cgroup_head *head = rtnl_dereference(tp->root); |
| 97 | struct cls_cgroup_head *new; |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 98 | struct tcf_ematch_tree t; |
| 99 | struct tcf_exts e; |
| 100 | int err; |
| 101 | |
Minoru Usui | 52ea3a5 | 2009-06-09 04:03:09 -0700 | [diff] [blame] | 102 | if (!tca[TCA_OPTIONS]) |
| 103 | return -EINVAL; |
| 104 | |
John Fastabend | 952313b | 2014-09-12 20:06:26 -0700 | [diff] [blame] | 105 | if (!head && !handle) |
| 106 | return -EINVAL; |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 107 | |
John Fastabend | 952313b | 2014-09-12 20:06:26 -0700 | [diff] [blame] | 108 | if (head && handle != head->handle) |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 109 | return -ENOENT; |
| 110 | |
John Fastabend | 952313b | 2014-09-12 20:06:26 -0700 | [diff] [blame] | 111 | new = kzalloc(sizeof(*head), GFP_KERNEL); |
| 112 | if (!new) |
| 113 | return -ENOBUFS; |
| 114 | |
John Fastabend | 9f6c38e | 2014-09-16 00:33:42 -0700 | [diff] [blame] | 115 | tcf_exts_init(&new->exts, TCA_CGROUP_ACT, TCA_CGROUP_POLICE); |
Jiri Pirko | 18b5427 | 2014-12-02 18:00:36 +0100 | [diff] [blame] | 116 | new->handle = handle; |
John Fastabend | 952313b | 2014-09-12 20:06:26 -0700 | [diff] [blame] | 117 | new->tp = tp; |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 118 | err = nla_parse_nested(tb, TCA_CGROUP_MAX, tca[TCA_OPTIONS], |
| 119 | cgroup_policy); |
| 120 | if (err < 0) |
John Fastabend | d14cbfc8 | 2014-09-15 23:31:17 -0700 | [diff] [blame] | 121 | goto errout; |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 122 | |
WANG Cong | 5da57f4 | 2013-12-15 20:15:07 -0800 | [diff] [blame] | 123 | tcf_exts_init(&e, TCA_CGROUP_ACT, TCA_CGROUP_POLICE); |
Cong Wang | 2f7ef2f | 2014-04-25 13:54:06 -0700 | [diff] [blame] | 124 | err = tcf_exts_validate(net, tp, tb, tca[TCA_RATE], &e, ovr); |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 125 | if (err < 0) |
John Fastabend | d14cbfc8 | 2014-09-15 23:31:17 -0700 | [diff] [blame] | 126 | goto errout; |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 127 | |
| 128 | err = tcf_em_tree_validate(tp, tb[TCA_CGROUP_EMATCHES], &t); |
John Fastabend | d14cbfc8 | 2014-09-15 23:31:17 -0700 | [diff] [blame] | 129 | if (err < 0) { |
WANG Cong | 18d0264 | 2014-09-25 10:26:37 -0700 | [diff] [blame] | 130 | tcf_exts_destroy(&e); |
John Fastabend | d14cbfc8 | 2014-09-15 23:31:17 -0700 | [diff] [blame] | 131 | goto errout; |
| 132 | } |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 133 | |
John Fastabend | 952313b | 2014-09-12 20:06:26 -0700 | [diff] [blame] | 134 | tcf_exts_change(tp, &new->exts, &e); |
| 135 | tcf_em_tree_change(tp, &new->ematches, &t); |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 136 | |
John Fastabend | 952313b | 2014-09-12 20:06:26 -0700 | [diff] [blame] | 137 | rcu_assign_pointer(tp->root, new); |
| 138 | if (head) |
| 139 | call_rcu(&head->rcu, cls_cgroup_destroy_rcu); |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 140 | return 0; |
John Fastabend | d14cbfc8 | 2014-09-15 23:31:17 -0700 | [diff] [blame] | 141 | errout: |
| 142 | kfree(new); |
| 143 | return err; |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 144 | } |
| 145 | |
| 146 | static void cls_cgroup_destroy(struct tcf_proto *tp) |
| 147 | { |
John Fastabend | 952313b | 2014-09-12 20:06:26 -0700 | [diff] [blame] | 148 | struct cls_cgroup_head *head = rtnl_dereference(tp->root); |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 149 | |
| 150 | if (head) { |
John Fastabend | 952313b | 2014-09-12 20:06:26 -0700 | [diff] [blame] | 151 | RCU_INIT_POINTER(tp->root, NULL); |
John Fastabend | 13990f8 | 2014-10-05 21:28:20 -0700 | [diff] [blame] | 152 | call_rcu(&head->rcu, cls_cgroup_destroy_rcu); |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 153 | } |
| 154 | } |
| 155 | |
| 156 | static int cls_cgroup_delete(struct tcf_proto *tp, unsigned long arg) |
| 157 | { |
| 158 | return -EOPNOTSUPP; |
| 159 | } |
| 160 | |
| 161 | static void cls_cgroup_walk(struct tcf_proto *tp, struct tcf_walker *arg) |
| 162 | { |
John Fastabend | 952313b | 2014-09-12 20:06:26 -0700 | [diff] [blame] | 163 | struct cls_cgroup_head *head = rtnl_dereference(tp->root); |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 164 | |
| 165 | if (arg->count < arg->skip) |
| 166 | goto skip; |
| 167 | |
| 168 | if (arg->fn(tp, (unsigned long) head, arg) < 0) { |
| 169 | arg->stop = 1; |
| 170 | return; |
| 171 | } |
| 172 | skip: |
| 173 | arg->count++; |
| 174 | } |
| 175 | |
WANG Cong | 832d1d5 | 2014-01-09 16:14:01 -0800 | [diff] [blame] | 176 | static int cls_cgroup_dump(struct net *net, struct tcf_proto *tp, unsigned long fh, |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 177 | struct sk_buff *skb, struct tcmsg *t) |
| 178 | { |
John Fastabend | 952313b | 2014-09-12 20:06:26 -0700 | [diff] [blame] | 179 | struct cls_cgroup_head *head = rtnl_dereference(tp->root); |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 180 | struct nlattr *nest; |
| 181 | |
| 182 | t->tcm_handle = head->handle; |
| 183 | |
| 184 | nest = nla_nest_start(skb, TCA_OPTIONS); |
| 185 | if (nest == NULL) |
| 186 | goto nla_put_failure; |
| 187 | |
WANG Cong | 5da57f4 | 2013-12-15 20:15:07 -0800 | [diff] [blame] | 188 | if (tcf_exts_dump(skb, &head->exts) < 0 || |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 189 | tcf_em_tree_dump(skb, &head->ematches, TCA_CGROUP_EMATCHES) < 0) |
| 190 | goto nla_put_failure; |
| 191 | |
| 192 | nla_nest_end(skb, nest); |
| 193 | |
WANG Cong | 5da57f4 | 2013-12-15 20:15:07 -0800 | [diff] [blame] | 194 | if (tcf_exts_dump_stats(skb, &head->exts) < 0) |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 195 | goto nla_put_failure; |
| 196 | |
| 197 | return skb->len; |
| 198 | |
| 199 | nla_put_failure: |
Jiri Pirko | 6ea3b44 | 2014-12-09 22:23:29 +0100 | [diff] [blame^] | 200 | nla_nest_cancel(skb, nest); |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 201 | return -1; |
| 202 | } |
| 203 | |
| 204 | static struct tcf_proto_ops cls_cgroup_ops __read_mostly = { |
| 205 | .kind = "cgroup", |
| 206 | .init = cls_cgroup_init, |
| 207 | .change = cls_cgroup_change, |
| 208 | .classify = cls_cgroup_classify, |
| 209 | .destroy = cls_cgroup_destroy, |
| 210 | .get = cls_cgroup_get, |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 211 | .delete = cls_cgroup_delete, |
| 212 | .walk = cls_cgroup_walk, |
| 213 | .dump = cls_cgroup_dump, |
| 214 | .owner = THIS_MODULE, |
| 215 | }; |
| 216 | |
| 217 | static int __init init_cgroup_cls(void) |
| 218 | { |
Daniel Borkmann | fe1217c | 2013-12-29 18:27:10 +0100 | [diff] [blame] | 219 | return register_tcf_proto_ops(&cls_cgroup_ops); |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 220 | } |
| 221 | |
| 222 | static void __exit exit_cgroup_cls(void) |
| 223 | { |
| 224 | unregister_tcf_proto_ops(&cls_cgroup_ops); |
Thomas Graf | f400923 | 2008-11-07 22:56:00 -0800 | [diff] [blame] | 225 | } |
| 226 | |
| 227 | module_init(init_cgroup_cls); |
| 228 | module_exit(exit_cgroup_cls); |
| 229 | MODULE_LICENSE("GPL"); |