// SPDX-License-Identifier: GPL-2.0-or-later /* * net/sched/cls_basic.c Basic Packet Classifier. * * Authors: Thomas Graf <tgraf@suug.ch> */ #include <linux/module.h> #include <linux/slab.h> #include <linux/types.h> #include <linux/kernel.h> #include <linux/string.h> #include <linux/errno.h> #include <linux/rtnetlink.h> #include <linux/skbuff.h> #include <linux/idr.h> #include <linux/percpu.h> #include <net/netlink.h> #include <net/act_api.h> #include <net/pkt_cls.h> struct basic_head { struct list_head flist; struct idr handle_idr; struct rcu_head rcu; }; struct basic_filter { u32 handle; struct tcf_exts exts; struct tcf_ematch_tree ematches; struct tcf_result res; struct tcf_proto *tp; struct list_head link; struct tc_basic_pcnt __percpu *pf; struct rcu_work rwork; }; static int basic_classify(struct sk_buff *skb, const struct tcf_proto *tp, struct tcf_result *res) { int r; struct basic_head *head = rcu_dereference_bh(tp->root); struct basic_filter *f; list_for_each_entry_rcu(f, &head->flist, link) { __this_cpu_inc(f->pf->rcnt); if (!tcf_em_tree_match(skb, &f->ematches, NULL)) continue; __this_cpu_inc(f->pf->rhit); *res = f->res; r = tcf_exts_exec(skb, &f->exts, res); if (r < 0) continue; return r; } return -1; } static void *basic_get(struct tcf_proto *tp, u32 handle) { struct basic_head *head = rtnl_dereference(tp->root); struct basic_filter *f; list_for_each_entry(f, &head->flist, link) { if (f->handle == handle) { return f; } } return NULL; } static int basic_init(struct tcf_proto *tp) { struct basic_head *head; head = kzalloc(sizeof(*head), GFP_KERNEL); if (head == NULL) return -ENOBUFS; INIT_LIST_HEAD(&head->flist); idr_init(&head->handle_idr); rcu_assign_pointer(tp->root, head); return 0; } static void __basic_delete_filter(struct basic_filter *f) { tcf_exts_destroy(&f->exts); tcf_em_tree_destroy(&f->ematches); tcf_exts_put_net(&f->exts); free_percpu(f->pf); kfree(f); } static void basic_delete_filter_work(struct work_struct *work) { struct basic_filter *f = container_of(to_rcu_work(work), struct basic_filter, rwork); rtnl_lock(); __basic_delete_filter(f); rtnl_unlock(); } static void basic_destroy(struct tcf_proto *tp, bool rtnl_held, struct netlink_ext_ack *extack) { struct basic_head *head = rtnl_dereference(tp->root); struct basic_filter *f, *n; list_for_each_entry_safe(f, n, &head->flist, link) { list_del_rcu(&f->link); tcf_unbind_filter(tp, &f->res); idr_remove(&head->handle_idr, f->handle); if (tcf_exts_get_net(&f->exts)) tcf_queue_work(&f->rwork, basic_delete_filter_work); else __basic_delete_filter(f); } idr_destroy(&head->handle_idr); kfree_rcu(head, rcu); } static int basic_delete(struct tcf_proto *tp, void *arg, bool *last, bool rtnl_held, struct netlink_ext_ack *extack) { struct basic_head *head = rtnl_dereference(tp->root); struct basic_filter *f = arg; list_del_rcu(&f->link); tcf_unbind_filter(tp, &f->res); idr_remove(&head->handle_idr, f->handle); tcf_exts_get_net(&f->exts); tcf_queue_work(&f->rwork, basic_delete_filter_work); *last = list_empty(&head->flist); return 0; } static const struct nla_policy basic_policy[TCA_BASIC_MAX + 1] = { [TCA_BASIC_CLASSID] = { .type = NLA_U32 }, [TCA_BASIC_EMATCHES] = { .type = NLA_NESTED }, }; static int basic_set_parms(struct net *net, struct tcf_proto *tp, struct basic_filter *f, unsigned long base, struct nlattr **tb, struct nlattr *est, u32 flags, struct netlink_ext_ack *extack) { int err; err = tcf_exts_validate(net, tp, tb, est, &f->exts, flags, extack); if (err < 0) return err; err = tcf_em_tree_validate(tp, tb[TCA_BASIC_EMATCHES], &f->ematches); if (err < 0) return err; if (tb[TCA_BASIC_CLASSID]) { f->res.classid = nla_get_u32(tb[TCA_BASIC_CLASSID]); tcf_bind_filter(tp, &f->res, base); } f->tp = tp; return 0; } static int basic_change(struct net *net, struct sk_buff *in_skb, struct tcf_proto *tp, unsigned long base, u32 handle, struct nlattr **tca, void **arg, u32 flags, struct netlink_ext_ack *extack) { int err; struct basic_head *head = rtnl_dereference(tp->root); struct nlattr *tb[TCA_BASIC_MAX + 1]; struct basic_filter *fold = (struct basic_filter *) *arg; struct basic_filter *fnew; if (tca[TCA_OPTIONS] == NULL) return -EINVAL; err = nla_parse_nested_deprecated(tb, TCA_BASIC_MAX, tca[TCA_OPTIONS], basic_policy, NULL); if (err < 0) return err; if (fold != NULL) { if (handle && fold->handle != handle) return -EINVAL; } fnew = kzalloc(sizeof(*fnew), GFP_KERNEL); if (!fnew) return -ENOBUFS; err = tcf_exts_init(&fnew->exts, net, TCA_BASIC_ACT, TCA_BASIC_POLICE); if (err < 0) goto errout; if (!handle) { handle = 1; err = idr_alloc_u32(&head->handle_idr, fnew, &handle, INT_MAX, GFP_KERNEL); } else if (!fold) { err = idr_alloc_u32(&head->handle_idr, fnew, &handle, handle, GFP_KERNEL); } if (err) goto errout; fnew->handle = handle; fnew->pf = alloc_percpu(struct tc_basic_pcnt); if (!fnew->pf) { err = -ENOMEM; goto errout; } err = basic_set_parms(net, tp, fnew, base, tb, tca[TCA_RATE], flags, extack); if (err < 0) { if (!fold) idr_remove(&head->handle_idr, fnew->handle); goto errout; } *arg = fnew; if (fold) { idr_replace(&head->handle_idr, fnew, fnew->handle); list_replace_rcu(&fold->link, &fnew->link); tcf_unbind_filter(tp, &fold->res); tcf_exts_get_net(&fold->exts); tcf_queue_work(&fold->rwork, basic_delete_filter_work); } else { list_add_rcu(&fnew->link, &head->flist); } return 0; errout: free_percpu(fnew->pf); tcf_exts_destroy(&fnew->exts); kfree(fnew); return err; } static void basic_walk(struct tcf_proto *tp, struct tcf_walker *arg, bool rtnl_held) { struct basic_head *head = rtnl_dereference(tp->root); struct basic_filter *f; list_for_each_entry(f, &head->flist, link) { if (arg->count < arg->skip) goto skip; if (arg->fn(tp, f, arg) < 0) { arg->stop = 1; break; } skip: arg->count++; } } static void basic_bind_class(void *fh, u32 classid, unsigned long cl, void *q, unsigned long base) { struct basic_filter *f = fh; if (f && f->res.classid == classid) { if (cl) __tcf_bind_filter(q, &f->res, base); else __tcf_unbind_filter(q, &f->res); } } static int basic_dump(struct net *net, struct tcf_proto *tp, void *fh, struct sk_buff *skb, struct tcmsg *t, bool rtnl_held) { struct tc_basic_pcnt gpf = {}; struct basic_filter *f = fh; struct nlattr *nest; int cpu; if (f == NULL) return skb->len; t->tcm_handle = f->handle; nest = nla_nest_start_noflag(skb, TCA_OPTIONS); if (nest == NULL) goto nla_put_failure; if (f->res.classid && nla_put_u32(skb, TCA_BASIC_CLASSID, f->res.classid)) goto nla_put_failure; for_each_possible_cpu(cpu) { struct tc_basic_pcnt *pf = per_cpu_ptr(f->pf, cpu); gpf.rcnt += pf->rcnt; gpf.rhit += pf->rhit; } if (nla_put_64bit(skb, TCA_BASIC_PCNT, sizeof(struct tc_basic_pcnt), &gpf, TCA_BASIC_PAD)) goto nla_put_failure; if (tcf_exts_dump(skb, &f->exts) < 0 || tcf_em_tree_dump(skb, &f->ematches, TCA_BASIC_EMATCHES) < 0) goto nla_put_failure; nla_nest_end(skb, nest); if (tcf_exts_dump_stats(skb, &f->exts) < 0) goto nla_put_failure; return skb->len; nla_put_failure: nla_nest_cancel(skb, nest); return -1; } static struct tcf_proto_ops cls_basic_ops __read_mostly = { .kind = "basic", .classify = basic_classify, .init = basic_init, .destroy = basic_destroy, .get = basic_get, .change = basic_change, .delete = basic_delete, .walk = basic_walk, .dump = basic_dump, .bind_class = basic_bind_class, .owner = THIS_MODULE, }; static int __init init_basic(void) { return register_tcf_proto_ops(&cls_basic_ops); } static void __exit exit_basic(void) { unregister_tcf_proto_ops(&cls_basic_ops); } module_init(init_basic) module_exit(exit_basic) MODULE_LICENSE("GPL");