diff options
Diffstat (limited to 'net')
| -rw-r--r-- | net/sched/Kconfig | 11 | ||||
| -rw-r--r-- | net/sched/Makefile | 1 | ||||
| -rw-r--r-- | net/sched/cls_cgroup.c | 290 |
3 files changed, 302 insertions, 0 deletions
diff --git a/net/sched/Kconfig b/net/sched/Kconfig index 6767e54..36543b6 100644 --- a/net/sched/Kconfig +++ b/net/sched/Kconfig @@ -316,6 +316,17 @@ config NET_CLS_FLOW To compile this code as a module, choose M here: the module will be called cls_flow. +config NET_CLS_CGROUP + bool "Control Group Classifier" + select NET_CLS + depends on CGROUPS + ---help--- + Say Y here if you want to classify packets based on the control + cgroup of their process. + + To compile this code as a module, choose M here: the + module will be called cls_cgroup. + config NET_EMATCH bool "Extended Matches" select NET_CLS diff --git a/net/sched/Makefile b/net/sched/Makefile index e60c992..70b35f8 100644 --- a/net/sched/Makefile +++ b/net/sched/Makefile @@ -38,6 +38,7 @@ obj-$(CONFIG_NET_CLS_TCINDEX) += cls_tcindex.o obj-$(CONFIG_NET_CLS_RSVP6) += cls_rsvp6.o obj-$(CONFIG_NET_CLS_BASIC) += cls_basic.o obj-$(CONFIG_NET_CLS_FLOW) += cls_flow.o +obj-$(CONFIG_NET_CLS_CGROUP) += cls_cgroup.o obj-$(CONFIG_NET_EMATCH) += ematch.o obj-$(CONFIG_NET_EMATCH_CMP) += em_cmp.o obj-$(CONFIG_NET_EMATCH_NBYTE) += em_nbyte.o diff --git a/net/sched/cls_cgroup.c b/net/sched/cls_cgroup.c new file mode 100644 index 0000000..53ada2c --- /dev/null +++ b/net/sched/cls_cgroup.c @@ -0,0 +1,290 @@ +/* + * net/sched/cls_cgroup.c Control Group Classifier + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + * + * Authors: Thomas Graf <tgraf@suug.ch> + */ + +#include <linux/module.h> +#include <linux/types.h> +#include <linux/string.h> +#include <linux/errno.h> +#include <linux/skbuff.h> +#include <linux/cgroup.h> +#include <net/rtnetlink.h> +#include <net/pkt_cls.h> + +struct cgroup_cls_state +{ + struct cgroup_subsys_state css; + u32 classid; +}; + +static inline struct cgroup_cls_state *net_cls_state(struct cgroup *cgrp) +{ + return (struct cgroup_cls_state *) + cgroup_subsys_state(cgrp, net_cls_subsys_id); +} + +static struct cgroup_subsys_state *cgrp_create(struct cgroup_subsys *ss, + struct cgroup *cgrp) +{ + struct cgroup_cls_state *cs; + + if (!(cs = kzalloc(sizeof(*cs), GFP_KERNEL))) + return ERR_PTR(-ENOMEM); + + if (cgrp->parent) + cs->classid = net_cls_state(cgrp->parent)->classid; + + return &cs->css; +} + +static void cgrp_destroy(struct cgroup_subsys *ss, struct cgroup *cgrp) +{ + kfree(ss); +} + +static u64 read_classid(struct cgroup *cgrp, struct cftype *cft) +{ + return net_cls_state(cgrp)->classid; +} + +static int write_classid(struct cgroup *cgrp, struct cftype *cft, u64 value) +{ + if (!cgroup_lock_live_group(cgrp)) + return -ENODEV; + + net_cls_state(cgrp)->classid = (u32) value; + + cgroup_unlock(); + + return 0; +} + +static struct cftype ss_files[] = { + { + .name = "classid", + .read_u64 = read_classid, + .write_u64 = write_classid, + }, +}; + +static int cgrp_populate(struct cgroup_subsys *ss, struct cgroup *cgrp) +{ + return cgroup_add_files(cgrp, ss, ss_files, ARRAY_SIZE(ss_files)); +} + +struct cgroup_subsys net_cls_subsys = { + .name = "net_cls", + .create = cgrp_create, + .destroy = cgrp_destroy, + .populate = cgrp_populate, + .subsys_id = net_cls_subsys_id, +}; + +struct cls_cgroup_head +{ + u32 handle; + struct tcf_exts exts; + struct tcf_ematch_tree ematches; +}; + +static int cls_cgroup_classify(struct sk_buff *skb, struct tcf_proto *tp, + struct tcf_result *res) +{ + struct cls_cgroup_head *head = tp->root; + struct cgroup_cls_state *cs; + int ret = 0; + + /* + * Due to the nature of the classifier it is required to ignore all + * packets originating from softirq context as accessing `current' + * would lead to false results. + * + * This test assumes that all callers of dev_queue_xmit() explicitely + * disable bh. Knowing this, it is possible to detect softirq based + * calls by looking at the number of nested bh disable calls because + * softirqs always disables bh. + */ + if (softirq_count() != SOFTIRQ_OFFSET) + return -1; + + rcu_read_lock(); + cs = (struct cgroup_cls_state *) task_subsys_state(current, + net_cls_subsys_id); + if (cs->classid && tcf_em_tree_match(skb, &head->ematches, NULL)) { + res->classid = cs->classid; + res->class = 0; + ret = tcf_exts_exec(skb, &head->exts, res); + } else + ret = -1; + + rcu_read_unlock(); + + return ret; +} + +static unsigned long cls_cgroup_get(struct tcf_proto *tp, u32 handle) +{ + return 0UL; +} + +static void cls_cgroup_put(struct tcf_proto *tp, unsigned long f) +{ +} + +static int cls_cgroup_init(struct tcf_proto *tp) +{ + return 0; +} + +static const struct tcf_ext_map cgroup_ext_map = { + .action = TCA_CGROUP_ACT, + .police = TCA_CGROUP_POLICE, +}; + +static const struct nla_policy cgroup_policy[TCA_CGROUP_MAX + 1] = { + [TCA_CGROUP_EMATCHES] = { .type = NLA_NESTED }, +}; + +static int cls_cgroup_change(struct tcf_proto *tp, unsigned long base, + u32 handle, struct nlattr **tca, + unsigned long *arg) +{ + struct nlattr *tb[TCA_CGROUP_MAX+1]; + struct cls_cgroup_head *head = tp->root; + struct tcf_ematch_tree t; + struct tcf_exts e; + int err; + + if (head == NULL) { + if (!handle) + return -EINVAL; + + head = kzalloc(sizeof(*head), GFP_KERNEL); + if (head == NULL) + return -ENOBUFS; + + head->handle = handle; + + tcf_tree_lock(tp); + tp->root = head; + tcf_tree_unlock(tp); + } + + if (handle != head->handle) + return -ENOENT; + + err = nla_parse_nested(tb, TCA_CGROUP_MAX, tca[TCA_OPTIONS], + cgroup_policy); + if (err < 0) + return err; + + err = tcf_exts_validate(tp, tb, tca[TCA_RATE], &e, &cgroup_ext_map); + if (err < 0) + return err; + + err = tcf_em_tree_validate(tp, tb[TCA_CGROUP_EMATCHES], &t); + if (err < 0) + return err; + + tcf_exts_change(tp, &head->exts, &e); + tcf_em_tree_change(tp, &head->ematches, &t); + + return 0; +} + +static void cls_cgroup_destroy(struct tcf_proto *tp) +{ + struct cls_cgroup_head *head; + + head = (struct cls_cgroup_head *)xchg(&tp->root, NULL); + + if (head) { + tcf_exts_destroy(tp, &head->exts); + tcf_em_tree_destroy(tp, &head->ematches); + kfree(head); + } +} + +static int cls_cgroup_delete(struct tcf_proto *tp, unsigned long arg) +{ + return -EOPNOTSUPP; +} + +static void cls_cgroup_walk(struct tcf_proto *tp, struct tcf_walker *arg) +{ + struct cls_cgroup_head *head = tp->root; + + if (arg->count < arg->skip) + goto skip; + + if (arg->fn(tp, (unsigned long) head, arg) < 0) { + arg->stop = 1; + return; + } +skip: + arg->count++; +} + +static int cls_cgroup_dump(struct tcf_proto *tp, unsigned long fh, + struct sk_buff *skb, struct tcmsg *t) +{ + struct cls_cgroup_head *head = tp->root; + unsigned char *b = skb_tail_pointer(skb); + struct nlattr *nest; + + t->tcm_handle = head->handle; + + nest = nla_nest_start(skb, TCA_OPTIONS); + if (nest == NULL) + goto nla_put_failure; + + if (tcf_exts_dump(skb, &head->exts, &cgroup_ext_map) < 0 || + tcf_em_tree_dump(skb, &head->ematches, TCA_CGROUP_EMATCHES) < 0) + goto nla_put_failure; + + nla_nest_end(skb, nest); + + if (tcf_exts_dump_stats(skb, &head->exts, &cgroup_ext_map) < 0) + goto nla_put_failure; + + return skb->len; + +nla_put_failure: + nlmsg_trim(skb, b); + return -1; +} + +static struct tcf_proto_ops cls_cgroup_ops __read_mostly = { + .kind = "cgroup", + .init = cls_cgroup_init, + .change = cls_cgroup_change, + .classify = cls_cgroup_classify, + .destroy = cls_cgroup_destroy, + .get = cls_cgroup_get, + .put = cls_cgroup_put, + .delete = cls_cgroup_delete, + .walk = cls_cgroup_walk, + .dump = cls_cgroup_dump, + .owner = THIS_MODULE, +}; + +static int __init init_cgroup_cls(void) +{ + return register_tcf_proto_ops(&cls_cgroup_ops); +} + +static void __exit exit_cgroup_cls(void) +{ + unregister_tcf_proto_ops(&cls_cgroup_ops); +} + +module_init(init_cgroup_cls); +module_exit(exit_cgroup_cls); +MODULE_LICENSE("GPL"); |
