309 lines · 6.5 KB · C
RawDownload
/* * net/sched/cls_basic.c	Basic Packet 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/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 <net/netlink.h>#include <net/act_api.h>#include <net/pkt_cls.h> struct basic_head {	u32			hgenerator;	struct list_head	flist;}; struct basic_filter {	u32			handle;	struct tcf_exts		exts;	struct tcf_ematch_tree	ematches;	struct tcf_result	res;	struct list_head	link;}; static const struct tcf_ext_map basic_ext_map = {	.action = TCA_BASIC_ACT,	.police = TCA_BASIC_POLICE}; static int basic_classify(struct sk_buff *skb, const struct tcf_proto *tp,			  struct tcf_result *res){	int r;	struct basic_head *head = (struct basic_head *) tp->root;	struct basic_filter *f; 	list_for_each_entry(f, &head->flist, link) {		if (!tcf_em_tree_match(skb, &f->ematches, NULL))			continue;		*res = f->res;		r = tcf_exts_exec(skb, &f->exts, res);		if (r < 0)			continue;		return r;	}	return -1;} static unsigned long basic_get(struct tcf_proto *tp, u32 handle){	unsigned long l = 0UL;	struct basic_head *head = (struct basic_head *) tp->root;	struct basic_filter *f; 	if (head == NULL)		return 0UL; 	list_for_each_entry(f, &head->flist, link)		if (f->handle == handle)			l = (unsigned long) f; 	return l;} static void basic_put(struct tcf_proto *tp, unsigned long f){} 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);	tp->root = head;	return 0;} static void basic_delete_filter(struct tcf_proto *tp, struct basic_filter *f){	tcf_unbind_filter(tp, &f->res);	tcf_exts_destroy(tp, &f->exts);	tcf_em_tree_destroy(tp, &f->ematches);	kfree(f);} static void basic_destroy(struct tcf_proto *tp){	struct basic_head *head = tp->root;	struct basic_filter *f, *n; 	list_for_each_entry_safe(f, n, &head->flist, link) {		list_del(&f->link);		basic_delete_filter(tp, f);	}	kfree(head);} static int basic_delete(struct tcf_proto *tp, unsigned long arg){	struct basic_head *head = (struct basic_head *) tp->root;	struct basic_filter *t, *f = (struct basic_filter *) arg; 	list_for_each_entry(t, &head->flist, link)		if (t == f) {			tcf_tree_lock(tp);			list_del(&t->link);			tcf_tree_unlock(tp);			basic_delete_filter(tp, t);			return 0;		} 	return -ENOENT;} 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){	int err;	struct tcf_exts e;	struct tcf_ematch_tree t; 	err = tcf_exts_validate(net, tp, tb, est, &e, &basic_ext_map);	if (err < 0)		return err; 	err = tcf_em_tree_validate(tp, tb[TCA_BASIC_EMATCHES], &t);	if (err < 0)		goto errout; 	if (tb[TCA_BASIC_CLASSID]) {		f->res.classid = nla_get_u32(tb[TCA_BASIC_CLASSID]);		tcf_bind_filter(tp, &f->res, base);	} 	tcf_exts_change(tp, &f->exts, &e);	tcf_em_tree_change(tp, &f->ematches, &t); 	return 0;errout:	tcf_exts_destroy(tp, &e);	return err;} static int basic_change(struct net *net, struct sk_buff *in_skb,			struct tcf_proto *tp, unsigned long base, u32 handle,			struct nlattr **tca, unsigned long *arg){	int err;	struct basic_head *head = (struct basic_head *) tp->root;	struct nlattr *tb[TCA_BASIC_MAX + 1];	struct basic_filter *f = (struct basic_filter *) *arg; 	if (tca[TCA_OPTIONS] == NULL)		return -EINVAL; 	err = nla_parse_nested(tb, TCA_BASIC_MAX, tca[TCA_OPTIONS],			       basic_policy);	if (err < 0)		return err; 	if (f != NULL) {		if (handle && f->handle != handle)			return -EINVAL;		return basic_set_parms(net, tp, f, base, tb, tca[TCA_RATE]);	} 	err = -ENOBUFS;	f = kzalloc(sizeof(*f), GFP_KERNEL);	if (f == NULL)		goto errout; 	err = -EINVAL;	if (handle)		f->handle = handle;	else {		unsigned int i = 0x80000000;		do {			if (++head->hgenerator == 0x7FFFFFFF)				head->hgenerator = 1;		} while (--i > 0 && basic_get(tp, head->hgenerator)); 		if (i <= 0) {			pr_err("Insufficient number of handles\n");			goto errout;		} 		f->handle = head->hgenerator;	} 	err = basic_set_parms(net, tp, f, base, tb, tca[TCA_RATE]);	if (err < 0)		goto errout; 	tcf_tree_lock(tp);	list_add(&f->link, &head->flist);	tcf_tree_unlock(tp);	*arg = (unsigned long) f; 	return 0;errout:	if (*arg == 0UL && f)		kfree(f); 	return err;} static void basic_walk(struct tcf_proto *tp, struct tcf_walker *arg){	struct basic_head *head = (struct basic_head *) 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, (unsigned long) f, arg) < 0) {			arg->stop = 1;			break;		}skip:		arg->count++;	}} static int basic_dump(struct tcf_proto *tp, unsigned long fh,		      struct sk_buff *skb, struct tcmsg *t){	struct basic_filter *f = (struct basic_filter *) fh;	struct nlattr *nest; 	if (f == NULL)		return skb->len; 	t->tcm_handle = f->handle; 	nest = nla_nest_start(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; 	if (tcf_exts_dump(skb, &f->exts, &basic_ext_map) < 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, &basic_ext_map) < 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,	.put		=	basic_put,	.change		=	basic_change,	.delete		=	basic_delete,	.walk		=	basic_walk,	.dump		=	basic_dump,	.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");