patch-2.1.99 linux/net/sched/cls_api.c

• Lines: 433
• Date: Tue Apr 28 11:10:11 1998
• Orig file: v2.1.98/linux/net/sched/cls_api.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.1.98/linux/net/sched/cls_api.c linux/net/sched/cls_api.c
@@ -0,0 +1,432 @@
+/*
+ * net/sched/cls_api.c	Packet classifier API.
+ *
+ *		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:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
+ */
+
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <asm/bitops.h>
+#include <linux/config.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/socket.h>
+#include <linux/sockios.h>
+#include <linux/in.h>
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+#include <linux/rtnetlink.h>
+#include <linux/init.h>
+#include <net/sock.h>
+#include <net/pkt_sched.h>
+
+/* The list of all installed classifier types */
+
+static struct tcf_proto_ops *tcf_proto_base;
+
+
+/* Find classifier type by string name */
+
+struct tcf_proto_ops * tcf_proto_lookup_ops(struct rtattr *kind)
+{
+	struct tcf_proto_ops *t;
+
+	if (kind) {
+		for (t = tcf_proto_base; t; t = t->next) {
+			if (rtattr_strcmp(kind, t->kind) == 0)
+				return t;
+		}
+	}
+	return NULL;
+}
+
+/* Register(unregister) new classifier type */
+
+int register_tcf_proto_ops(struct tcf_proto_ops *ops)
+{
+	struct tcf_proto_ops *t, **tp;
+
+	for (tp = &tcf_proto_base; (t=*tp) != NULL; tp = &t->next)
+		if (strcmp(ops->kind, t->kind) == 0)
+			return -EEXIST;
+
+	ops->next = NULL;
+	*tp = ops;
+	return 0;
+}
+
+int unregister_tcf_proto_ops(struct tcf_proto_ops *ops)
+{
+	struct tcf_proto_ops *t, **tp;
+
+	for (tp = &tcf_proto_base; (t=*tp) != NULL; tp = &t->next)
+		if (t == ops)
+			break;
+
+	if (!t)
+		return -ENOENT;
+	*tp = t->next;
+	return 0;
+}
+
+#ifdef CONFIG_RTNETLINK
+
+static int tfilter_notify(struct sk_buff *oskb, struct nlmsghdr *n,
+			  struct tcf_proto *tp, unsigned long fh, int event);
+
+
+/* Select new prio value from the range, managed by kernel. */
+
+static __inline__ u32 tcf_auto_prio(struct tcf_proto *tp, u32 prio)
+{
+	u32 first = TC_H_MAKE(0xC0000000U,0U);
+
+	if (!tp || tp->next == NULL)
+		return first;
+
+	if (prio == TC_H_MAKE(0xFFFF0000U,0U))
+		first = tp->prio+1; 
+	else
+		first = tp->prio-1;
+
+	if (first == prio)
+		first = tp->prio;
+
+	return first;
+}
+
+/* Add/change/delete/get a filter node */
+
+static int tc_ctl_tfilter(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
+{
+	struct rtattr **tca = arg;
+	struct tcmsg *t = NLMSG_DATA(n);
+	u32 protocol = TC_H_MIN(t->tcm_info);
+	u32 prio = TC_H_MAJ(t->tcm_info);
+	u32 nprio = prio;
+	struct device *dev;
+	struct Qdisc  *q;
+	struct tcf_proto **back, **chain;
+	struct tcf_proto *tp = NULL;
+	struct tcf_proto_ops *tp_ops;
+	struct Qdisc_class_ops *cops;
+	unsigned long cl = 0;
+	unsigned long fh;
+	int err;
+
+	if (prio == 0) {
+		/* If no priority is given, user wants we allocated it. */
+		if (n->nlmsg_type != RTM_NEWTFILTER || !(n->nlmsg_flags&NLM_F_CREATE))
+			return -ENOENT;
+		if (n->nlmsg_flags&NLM_F_APPEND)
+			prio = TC_H_MAKE(0xFFFF0000U,0U);
+		else
+			prio = TC_H_MAKE(0x80000000U,0U);
+	}
+
+	/* Find head of filter chain. */
+
+	/* Find link */
+	if ((dev = dev_get_by_index(t->tcm_ifindex)) == NULL)
+		return -ENODEV;
+
+	/* Find qdisc */
+	if (!t->tcm_parent)
+		q = dev->qdisc_sleeping;
+	else if ((q = qdisc_lookup(dev, TC_H_MAJ(t->tcm_parent))) == NULL)
+		return -EINVAL;
+
+	/* Is it classful? */
+	if ((cops = q->ops->cl_ops) == NULL)
+		return -EINVAL;
+
+	/* Do we search for filter, attached to class? */
+	if (TC_H_MIN(t->tcm_parent)) {
+		cl = cops->get(q, t->tcm_parent);
+		if (cl == 0)
+			return -ENOENT;
+	}
+
+	/* And the last stroke */
+	chain = cops->tcf_chain(q, cl);
+	err = -EINVAL;
+	if (chain == NULL)
+		goto errout;
+
+	/* Check the chain for existence of proto-tcf with this priority */
+	for (back = chain; (tp=*back) != NULL; back = &tp->next) {
+		if (tp->prio >= prio) {
+			if (tp->prio == prio) {
+				if (!nprio || (tp->protocol != protocol && protocol))
+					goto errout;
+			} else
+				tp = NULL;
+			break;
+		}
+	}
+
+	if (tp == NULL) {
+		/* Proto-tcf does not exist, create new one */
+
+		if (tca[TCA_KIND-1] == NULL || !protocol)
+			goto errout;
+
+		err = -ENOENT;
+		if (n->nlmsg_type != RTM_NEWTFILTER || !(n->nlmsg_flags&NLM_F_CREATE))
+			goto errout;
+
+
+		/* Create new proto tcf */
+
+		err = -ENOBUFS;
+		if ((tp = kmalloc(sizeof(*tp), GFP_KERNEL)) == NULL)
+			goto errout;
+		tp_ops = tcf_proto_lookup_ops(tca[TCA_KIND-1]);
+		if (tp_ops == NULL) {
+			err = -EINVAL;
+			kfree(tp);
+			goto errout;
+		}
+		memset(tp, 0, sizeof(*tp));
+		tp->ops = tp_ops;
+		tp->protocol = protocol;
+		tp->prio = nprio ? : tcf_auto_prio(*back, prio);
+		tp->q = q;
+		tp->classify = tp_ops->classify;
+		tp->classid = t->tcm_parent;
+		err = tp_ops->init(tp);
+		if (err) {
+			kfree(tp);
+			goto errout;
+		}
+		tp->next = *back;
+		*back = tp;
+	} else if (tca[TCA_KIND-1] && rtattr_strcmp(tca[TCA_KIND-1], tp->ops->kind))
+		goto errout;
+
+	fh = tp->ops->get(tp, t->tcm_handle);
+
+	if (fh == 0) {
+		if (n->nlmsg_type == RTM_DELTFILTER && t->tcm_handle == 0) {
+			*back = tp->next;
+			tp->ops->destroy(tp);
+			kfree(tp);
+			err = 0;
+			goto errout;
+		}
+
+		err = -ENOENT;
+		if (n->nlmsg_type != RTM_NEWTFILTER || !(n->nlmsg_flags&NLM_F_CREATE))
+			goto errout;
+	} else {
+		switch (n->nlmsg_type) {
+		case RTM_NEWTFILTER:	
+			err = -EEXIST;
+			if (n->nlmsg_flags&NLM_F_EXCL)
+				goto errout;
+			break;
+		case RTM_DELTFILTER:
+			err = tp->ops->delete(tp, fh);
+			goto errout;
+		case RTM_GETTFILTER:
+			err = tfilter_notify(skb, n, tp, fh, RTM_NEWTFILTER);
+			goto errout;
+		default:
+			err = -EINVAL;
+			goto errout;
+		}
+	}
+
+	err = tp->ops->change(tp, t->tcm_handle, tca, &fh);
+	if (err == 0)
+		tfilter_notify(skb, n, tp, fh, RTM_NEWTFILTER);
+
+errout:
+	if (cl)
+		cops->put(q, cl);
+	return err;
+}
+
+static int
+tcf_fill_node(struct sk_buff *skb, struct tcf_proto *tp, unsigned long fh,
+	      u32 pid, u32 seq, unsigned flags, int event)
+{
+	struct tcmsg *tcm;
+	struct nlmsghdr  *nlh;
+	unsigned char	 *b = skb->tail;
+
+	nlh = NLMSG_PUT(skb, pid, seq, event, sizeof(*tcm));
+	nlh->nlmsg_flags = flags;
+	tcm = NLMSG_DATA(nlh);
+	tcm->tcm_family = AF_UNSPEC;
+	tcm->tcm_ifindex = tp->q->dev->ifindex;
+	tcm->tcm_parent = tp->classid;
+	tcm->tcm_handle = 0;
+	tcm->tcm_info = TC_H_MAKE(tp->prio, tp->protocol);
+	RTA_PUT(skb, TCA_KIND, IFNAMSIZ, tp->ops->kind);
+	if (tp->ops->dump && tp->ops->dump(tp, fh, skb, tcm) < 0)
+		goto rtattr_failure;
+	nlh->nlmsg_len = skb->tail - b;
+	return skb->len;
+
+nlmsg_failure:
+rtattr_failure:
+	skb_trim(skb, b - skb->data);
+	return -1;
+}
+
+static int tfilter_notify(struct sk_buff *oskb, struct nlmsghdr *n,
+			  struct tcf_proto *tp, unsigned long fh, int event)
+{
+	struct sk_buff *skb;
+	pid_t pid = oskb ? NETLINK_CB(oskb).pid : 0;
+
+	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
+	if (!skb)
+		return -ENOBUFS;
+
+	if (tcf_fill_node(skb, tp, fh, pid, n->nlmsg_seq, 0, event) <= 0) {
+		kfree_skb(skb);
+		return -EINVAL;
+	}
+
+	return rtnetlink_send(skb, pid, RTMGRP_TC, n->nlmsg_flags&NLM_F_ECHO);
+}
+
+struct tcf_dump_args
+{
+	struct tcf_walker w;
+	struct sk_buff *skb;
+	struct netlink_callback *cb;
+};
+
+static int tcf_node_dump(struct tcf_proto *tp, unsigned long n, struct tcf_walker *arg)
+{
+	struct tcf_dump_args *a = (void*)arg;
+
+	return tcf_fill_node(a->skb, tp, n, NETLINK_CB(a->cb->skb).pid,
+			     a->cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWTFILTER);
+}
+
+static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb)
+{
+	int t;
+	int s_t;
+	struct device *dev;
+	struct Qdisc *q;
+	struct tcf_proto *tp, **chain;
+	struct tcmsg *tcm = (struct tcmsg*)NLMSG_DATA(cb->nlh);
+	unsigned long cl = 0;
+	struct Qdisc_class_ops *cops;
+	struct tcf_dump_args arg;
+
+	if (cb->nlh->nlmsg_len < NLMSG_LENGTH(sizeof(*tcm)))
+		return skb->len;
+	if ((dev = dev_get_by_index(tcm->tcm_ifindex)) == NULL)
+		return skb->len;
+	if ((q = qdisc_lookup(dev, tcm->tcm_parent)) == NULL)
+		return skb->len;
+	cops = q->ops->cl_ops;
+	if (TC_H_MIN(tcm->tcm_parent)) {
+		if (cops)
+			cl = cops->get(q, tcm->tcm_parent);
+		if (cl == 0)
+			goto errout;
+	}
+	chain = cops->tcf_chain(q, cl);
+	if (chain == NULL)
+		goto errout;
+
+	s_t = cb->args[0];
+
+	for (tp=*chain, t=0; tp; tp = tp->next, t++) {
+		if (t < s_t) continue;
+		if (TC_H_MAJ(tcm->tcm_info) &&
+		    TC_H_MAJ(tcm->tcm_info) != tp->prio)
+			continue;
+		if (TC_H_MIN(tcm->tcm_info) &&
+		    TC_H_MIN(tcm->tcm_info) != tp->protocol)
+			continue;
+		if (t > s_t)
+			memset(&cb->args[1], 0, sizeof(cb->args)-sizeof(int));
+		if (cb->args[1] == 0) {
+			if (tcf_fill_node(skb, tp, 0, NETLINK_CB(cb->skb).pid,
+					  cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWTFILTER) <= 0) {
+				break;
+			}
+			cb->args[1] = 1;
+		}
+		if (tp->ops->walk == NULL)
+			continue;
+		arg.w.fn = tcf_node_dump;
+		arg.skb = skb;
+		arg.cb = cb;
+		arg.w.stop = 0;
+		arg.w.skip = cb->args[1]-1;
+		arg.w.count = 0;
+		tp->ops->walk(tp, &arg.w);
+		cb->args[1] = arg.w.count+1;
+		if (arg.w.stop)
+			break;
+	}
+
+	cb->args[0] = t;
+
+errout:
+	if (cl)
+		cops->put(q, cl);
+
+	return skb->len;
+}
+
+#endif
+
+
+__initfunc(int tc_filter_init(void))
+{
+#ifdef CONFIG_RTNETLINK
+	struct rtnetlink_link *link_p = rtnetlink_links[AF_UNSPEC];
+
+	/* Setup rtnetlink links. It is made here to avoid
+	   exporting large number of public symbols.
+	 */
+
+	if (link_p) {
+		link_p[RTM_NEWTFILTER-RTM_BASE].doit = tc_ctl_tfilter;
+		link_p[RTM_DELTFILTER-RTM_BASE].doit = tc_ctl_tfilter;
+		link_p[RTM_GETTFILTER-RTM_BASE].doit = tc_ctl_tfilter;
+		link_p[RTM_GETTFILTER-RTM_BASE].dumpit = tc_dump_tfilter;
+	}
+#endif
+#define INIT_TC_FILTER(name) { \
+          extern struct tcf_proto_ops cls_##name##_ops; \
+          register_tcf_proto_ops(&cls_##name##_ops); \
+	}
+
+#ifdef CONFIG_NET_CLS_U32
+	INIT_TC_FILTER(u32);
+#endif
+#ifdef CONFIG_NET_CLS_ROUTE
+	INIT_TC_FILTER(route);
+#endif
+#ifdef CONFIG_NET_CLS_FW
+	INIT_TC_FILTER(fw);
+#endif
+#ifdef CONFIG_NET_CLS_RSVP
+	INIT_TC_FILTER(rsvp);
+#endif
+#ifdef CONFIG_NET_CLS_RSVP6
+	INIT_TC_FILTER(rsvp6);
+#endif
+	return 0;
+}