diff mbox series

[net-next] ipmr: ip6mr: Create new sockopt to clear mfc cache or vifs

Message ID 20190208041103.31299-2-callum.sinclair@alliedtelesis.co.nz
State Changes Requested
Delegated to: David Miller
Headers show
Series [net-next] ipmr: ip6mr: Create new sockopt to clear mfc cache or vifs | expand

Commit Message

Callum Sinclair Feb. 8, 2019, 4:11 a.m. UTC 
Currently the only way to clear the mfc cache was to delete the entries
one by one using the MRT_DEL_MFC socket option or to destroy and
recreate the socket.

Create a new socket option which will clear the multicast forwarding
cache on the socket without destroying the socket. The new socket option
MRT_FLUSH_ENTRIES will clear all multicast entries on the sockets table
and the MRT_FLUSH_VIFS will delete all multicast vifs on the socket
table.

Signed-off-by: Callum Sinclair <callum.sinclair@alliedtelesis.co.nz>
---
 include/uapi/linux/mroute.h  |  7 +++-
 include/uapi/linux/mroute6.h |  7 +++-
 net/ipv4/ipmr.c              | 69 ++++++++++++++++++++-------------
 net/ipv6/ip6mr.c             | 74 ++++++++++++++++++++++--------------
 4 files changed, 100 insertions(+), 57 deletions(-)

Comments

Nicolas Dichtel Feb. 8, 2019, 2:18 p.m. UTC | #1 
Le 08/02/2019 à 05:11, Callum Sinclair a écrit :
> Currently the only way to clear the mfc cache was to delete the entries
mfc stands for 'multicast forwarding cache', so 'mfc cache' is a bit strange.

> one by one using the MRT_DEL_MFC socket option or to destroy and
> recreate the socket.
Note that if entries were added with MRT_ADD_MFC_PROXY, they will survive to the
socket destruction. This is not the case with your new cmd. Is it intended?
Maybe a third option (something like MRT_FLUSH_MFC_PROXY) would be useful to
avoid confusion?

> 
> Create a new socket option which will clear the multicast forwarding
> cache on the socket without destroying the socket. The new socket option
> MRT_FLUSH_ENTRIES will clear all multicast entries on the sockets table
> and the MRT_FLUSH_VIFS will delete all multicast vifs on the socket
> table.
> 
> Signed-off-by: Callum Sinclair <callum.sinclair@alliedtelesis.co.nz>
> ---
>  include/uapi/linux/mroute.h  |  7 +++-
>  include/uapi/linux/mroute6.h |  7 +++-
>  net/ipv4/ipmr.c              | 69 ++++++++++++++++++++-------------
>  net/ipv6/ip6mr.c             | 74 ++++++++++++++++++++++--------------
>  4 files changed, 100 insertions(+), 57 deletions(-)
> 
> diff --git a/include/uapi/linux/mroute.h b/include/uapi/linux/mroute.h
> index 5d37a9ccce63..673495ca3495 100644
> --- a/include/uapi/linux/mroute.h
> +++ b/include/uapi/linux/mroute.h
> @@ -28,12 +28,17 @@
>  #define MRT_TABLE	(MRT_BASE+9)	/* Specify mroute table ID		*/
>  #define MRT_ADD_MFC_PROXY	(MRT_BASE+10)	/* Add a (*,*|G) mfc entry	*/
>  #define MRT_DEL_MFC_PROXY	(MRT_BASE+11)	/* Del a (*,*|G) mfc entry	*/
> -#define MRT_MAX		(MRT_BASE+11)
> +#define MRT_FLUSH	(MRT_BASE+12)	/* Flush all multicast entries and vifs	*/
nit: "Flush all mfc entries and/or vifs" ?

> +#define MRT_MAX		(MRT_BASE+12)
>  
>  #define SIOCGETVIFCNT	SIOCPROTOPRIVATE	/* IP protocol privates */
>  #define SIOCGETSGCNT	(SIOCPROTOPRIVATE+1)
>  #define SIOCGETRPF	(SIOCPROTOPRIVATE+2)
>  
> +/* MRT_FLUSH optional flags */
> +#define MRT_FLUSH_ENTRIES	1	/* For flushing all multicast entries */
Maybe MRT_FLUSH_MFC is more consistent with the previous naming (MRT_ADD_MFC, etc.)


Regards,
Nicolas
Nikolay Aleksandrov Feb. 8, 2019, 2:43 p.m. UTC | #2 
On 08/02/2019 16:18, Nicolas Dichtel wrote:
> Le 08/02/2019 à 05:11, Callum Sinclair a écrit :
>> Currently the only way to clear the mfc cache was to delete the entries
> mfc stands for 'multicast forwarding cache', so 'mfc cache' is a bit strange.
> 
>> one by one using the MRT_DEL_MFC socket option or to destroy and
>> recreate the socket.
> Note that if entries were added with MRT_ADD_MFC_PROXY, they will survive to the
> socket destruction. This is not the case with your new cmd. Is it intended?

I think you're referring to MFC_STATIC entries (sk != mroute_sk). It
doesn't matter how you add an entry - they all get cleaned up if added
through the mroute socket.

> Maybe a third option (something like MRT_FLUSH_MFC_PROXY) would be useful to
> avoid confusion?
> 
>>
>> Create a new socket option which will clear the multicast forwarding
>> cache on the socket without destroying the socket. The new socket option
>> MRT_FLUSH_ENTRIES will clear all multicast entries on the sockets table
>> and the MRT_FLUSH_VIFS will delete all multicast vifs on the socket
>> table.
>>
>> Signed-off-by: Callum Sinclair <callum.sinclair@alliedtelesis.co.nz>
>> ---
>>  include/uapi/linux/mroute.h  |  7 +++-
>>  include/uapi/linux/mroute6.h |  7 +++-
>>  net/ipv4/ipmr.c              | 69 ++++++++++++++++++++-------------
>>  net/ipv6/ip6mr.c             | 74 ++++++++++++++++++++++--------------
>>  4 files changed, 100 insertions(+), 57 deletions(-)
>>
>> diff --git a/include/uapi/linux/mroute.h b/include/uapi/linux/mroute.h
>> index 5d37a9ccce63..673495ca3495 100644
>> --- a/include/uapi/linux/mroute.h
>> +++ b/include/uapi/linux/mroute.h
>> @@ -28,12 +28,17 @@
>>  #define MRT_TABLE	(MRT_BASE+9)	/* Specify mroute table ID		*/
>>  #define MRT_ADD_MFC_PROXY	(MRT_BASE+10)	/* Add a (*,*|G) mfc entry	*/
>>  #define MRT_DEL_MFC_PROXY	(MRT_BASE+11)	/* Del a (*,*|G) mfc entry	*/
>> -#define MRT_MAX		(MRT_BASE+11)
>> +#define MRT_FLUSH	(MRT_BASE+12)	/* Flush all multicast entries and vifs	*/
> nit: "Flush all mfc entries and/or vifs" ?
> 
>> +#define MRT_MAX		(MRT_BASE+12)
>>  
>>  #define SIOCGETVIFCNT	SIOCPROTOPRIVATE	/* IP protocol privates */
>>  #define SIOCGETSGCNT	(SIOCPROTOPRIVATE+1)
>>  #define SIOCGETRPF	(SIOCPROTOPRIVATE+2)
>>  
>> +/* MRT_FLUSH optional flags */
>> +#define MRT_FLUSH_ENTRIES	1	/* For flushing all multicast entries */
> Maybe MRT_FLUSH_MFC is more consistent with the previous naming (MRT_ADD_MFC, etc.)
> 
> 
> Regards,
> Nicolas
>
Nicolas Dichtel Feb. 8, 2019, 3:08 p.m. UTC | #3 
Le 08/02/2019 à 15:43, Nikolay Aleksandrov a écrit :
> On 08/02/2019 16:18, Nicolas Dichtel wrote:
>> Le 08/02/2019 à 05:11, Callum Sinclair a écrit :
>>> Currently the only way to clear the mfc cache was to delete the entries
>> mfc stands for 'multicast forwarding cache', so 'mfc cache' is a bit strange.
>>
>>> one by one using the MRT_DEL_MFC socket option or to destroy and
>>> recreate the socket.
>> Note that if entries were added with MRT_ADD_MFC_PROXY, they will survive to the
>> socket destruction. This is not the case with your new cmd. Is it intended?
> 
> I think you're referring to MFC_STATIC entries (sk != mroute_sk). It
> doesn't matter how you add an entry - they all get cleaned up if added
> through the mroute socket.
Yes, right.
MRT_FLUSH_MFC_STATIC ?
Nikolay Aleksandrov Feb. 8, 2019, 9:40 p.m. UTC | #4 
On 08/02/2019 17:08, Nicolas Dichtel wrote:
> Le 08/02/2019 à 15:43, Nikolay Aleksandrov a écrit :
>> On 08/02/2019 16:18, Nicolas Dichtel wrote:
>>> Le 08/02/2019 à 05:11, Callum Sinclair a écrit :
>>>> Currently the only way to clear the mfc cache was to delete the entries
>>> mfc stands for 'multicast forwarding cache', so 'mfc cache' is a bit strange.
>>>
>>>> one by one using the MRT_DEL_MFC socket option or to destroy and
>>>> recreate the socket.
>>> Note that if entries were added with MRT_ADD_MFC_PROXY, they will survive to the
>>> socket destruction. This is not the case with your new cmd. Is it intended?
>>
>> I think you're referring to MFC_STATIC entries (sk != mroute_sk). It
>> doesn't matter how you add an entry - they all get cleaned up if added
>> through the mroute socket.
> Yes, right.
> MRT_FLUSH_MFC_STATIC ?
> 

Sounds good to me.
diff mbox series

Patch

diff --git a/include/uapi/linux/mroute.h b/include/uapi/linux/mroute.h
index 5d37a9ccce63..673495ca3495 100644
--- a/include/uapi/linux/mroute.h
+++ b/include/uapi/linux/mroute.h
@@ -28,12 +28,17 @@ 
 #define MRT_TABLE	(MRT_BASE+9)	/* Specify mroute table ID		*/
 #define MRT_ADD_MFC_PROXY	(MRT_BASE+10)	/* Add a (*,*|G) mfc entry	*/
 #define MRT_DEL_MFC_PROXY	(MRT_BASE+11)	/* Del a (*,*|G) mfc entry	*/
-#define MRT_MAX		(MRT_BASE+11)
+#define MRT_FLUSH	(MRT_BASE+12)	/* Flush all multicast entries and vifs	*/
+#define MRT_MAX		(MRT_BASE+12)
 
 #define SIOCGETVIFCNT	SIOCPROTOPRIVATE	/* IP protocol privates */
 #define SIOCGETSGCNT	(SIOCPROTOPRIVATE+1)
 #define SIOCGETRPF	(SIOCPROTOPRIVATE+2)
 
+/* MRT_FLUSH optional flags */
+#define MRT_FLUSH_ENTRIES	1	/* For flushing all multicast entries */
+#define MRT_FLUSH_VIFS		2	/* For flushing all multicast vifs */
+
 #define MAXVIFS		32
 typedef unsigned long vifbitmap_t;	/* User mode code depends on this lot */
 typedef unsigned short vifi_t;
diff --git a/include/uapi/linux/mroute6.h b/include/uapi/linux/mroute6.h
index 9999cc006390..1f7ac3f0bc20 100644
--- a/include/uapi/linux/mroute6.h
+++ b/include/uapi/linux/mroute6.h
@@ -31,12 +31,17 @@ 
 #define MRT6_TABLE	(MRT6_BASE+9)	/* Specify mroute table ID		*/
 #define MRT6_ADD_MFC_PROXY	(MRT6_BASE+10)	/* Add a (*,*|G) mfc entry	*/
 #define MRT6_DEL_MFC_PROXY	(MRT6_BASE+11)	/* Del a (*,*|G) mfc entry	*/
-#define MRT6_MAX	(MRT6_BASE+11)
+#define MRT6_FLUSH	(MRT6_BASE+12)	/* Flush all multicast entries and vifs	*/
+#define MRT6_MAX	(MRT6_BASE+12)
 
 #define SIOCGETMIFCNT_IN6	SIOCPROTOPRIVATE	/* IP protocol privates */
 #define SIOCGETSGCNT_IN6	(SIOCPROTOPRIVATE+1)
 #define SIOCGETRPF	(SIOCPROTOPRIVATE+2)
 
+/* MRT6_FLUSH optional flags */
+#define MRT6_FLUSH_ENTRIES	1	/* For flushing all multicast entries */
+#define MRT6_FLUSH_VIFS		2	/* For flushing all multicast vifs */
+
 #define MAXMIFS		32
 typedef unsigned long mifbitmap_t;	/* User mode code depends on this lot */
 typedef unsigned short mifi_t;
diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c
index e536970557dd..dc7a4ee1d7ca 100644
--- a/net/ipv4/ipmr.c
+++ b/net/ipv4/ipmr.c
@@ -110,7 +110,7 @@  static int ipmr_cache_report(struct mr_table *mrt,
 static void mroute_netlink_event(struct mr_table *mrt, struct mfc_cache *mfc,
 				 int cmd);
 static void igmpmsg_netlink_event(struct mr_table *mrt, struct sk_buff *pkt);
-static void mroute_clean_tables(struct mr_table *mrt, bool all);
+static void mroute_clean_tables(struct mr_table *mrt, bool all, int flags);
 static void ipmr_expire_process(struct timer_list *t);
 
 #ifdef CONFIG_IP_MROUTE_MULTIPLE_TABLES
@@ -415,7 +415,7 @@  static struct mr_table *ipmr_new_table(struct net *net, u32 id)
 static void ipmr_free_table(struct mr_table *mrt)
 {
 	del_timer_sync(&mrt->ipmr_expire_timer);
-	mroute_clean_tables(mrt, true);
+	mroute_clean_tables(mrt, true, MRT_FLUSH_VIFS | MRT_FLUSH_ENTRIES);
 	rhltable_destroy(&mrt->mfc_hash);
 	kfree(mrt);
 }
@@ -1296,7 +1296,7 @@  static int ipmr_mfc_add(struct net *net, struct mr_table *mrt,
 }
 
 /* Close the multicast socket, and clear the vif tables etc */
-static void mroute_clean_tables(struct mr_table *mrt, bool all)
+static void mroute_clean_tables(struct mr_table *mrt, bool all, int flags)
 {
 	struct net *net = read_pnet(&mrt->net);
 	struct mr_mfc *c, *tmp;
@@ -1305,35 +1305,39 @@  static void mroute_clean_tables(struct mr_table *mrt, bool all)
 	int i;
 
 	/* Shut down all active vif entries */
-	for (i = 0; i < mrt->maxvif; i++) {
-		if (!all && (mrt->vif_table[i].flags & VIFF_STATIC))
-			continue;
-		vif_delete(mrt, i, 0, &list);
+	if (flags & MRT_FLUSH_VIFS) {
+		for (i = 0; i < mrt->maxvif; i++) {
+			if (!all && (mrt->vif_table[i].flags & VIFF_STATIC))
+				continue;
+			vif_delete(mrt, i, 0, &list);
+		}
+		unregister_netdevice_many(&list);
 	}
-	unregister_netdevice_many(&list);
 
 	/* Wipe the cache */
-	list_for_each_entry_safe(c, tmp, &mrt->mfc_cache_list, list) {
-		if (!all && (c->mfc_flags & MFC_STATIC))
-			continue;
-		rhltable_remove(&mrt->mfc_hash, &c->mnode, ipmr_rht_params);
-		list_del_rcu(&c->list);
-		cache = (struct mfc_cache *)c;
-		call_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_DEL, cache,
-					      mrt->id);
-		mroute_netlink_event(mrt, cache, RTM_DELROUTE);
-		mr_cache_put(c);
-	}
-
-	if (atomic_read(&mrt->cache_resolve_queue_len) != 0) {
-		spin_lock_bh(&mfc_unres_lock);
-		list_for_each_entry_safe(c, tmp, &mrt->mfc_unres_queue, list) {
-			list_del(&c->list);
+	if (flags & MRT_FLUSH_ENTRIES) {
+		list_for_each_entry_safe(c, tmp, &mrt->mfc_cache_list, list) {
+			if (!all && (c->mfc_flags & MFC_STATIC))
+				continue;
+			rhltable_remove(&mrt->mfc_hash, &c->mnode, ipmr_rht_params);
+			list_del_rcu(&c->list);
 			cache = (struct mfc_cache *)c;
+			call_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_DEL, cache,
+										  mrt->id);
 			mroute_netlink_event(mrt, cache, RTM_DELROUTE);
-			ipmr_destroy_unres(mrt, cache);
+			mr_cache_put(c);
+		}
+
+		if (atomic_read(&mrt->cache_resolve_queue_len) != 0) {
+			spin_lock_bh(&mfc_unres_lock);
+			list_for_each_entry_safe(c, tmp, &mrt->mfc_unres_queue, list) {
+				list_del(&c->list);
+				cache = (struct mfc_cache *)c;
+				mroute_netlink_event(mrt, cache, RTM_DELROUTE);
+				ipmr_destroy_unres(mrt, cache);
+			}
+			spin_unlock_bh(&mfc_unres_lock);
 		}
-		spin_unlock_bh(&mfc_unres_lock);
 	}
 }
 
@@ -1354,7 +1358,7 @@  static void mrtsock_destruct(struct sock *sk)
 						    NETCONFA_IFINDEX_ALL,
 						    net->ipv4.devconf_all);
 			RCU_INIT_POINTER(mrt->mroute_sk, NULL);
-			mroute_clean_tables(mrt, false);
+			mroute_clean_tables(mrt, false, MRT_FLUSH_VIFS | MRT_FLUSH_ENTRIES);
 		}
 	}
 	rtnl_unlock();
@@ -1479,6 +1483,17 @@  int ip_mroute_setsockopt(struct sock *sk, int optname, char __user *optval,
 					   sk == rtnl_dereference(mrt->mroute_sk),
 					   parent);
 		break;
+	case MRT_FLUSH:
+		if (optlen != sizeof(val)) {
+			ret = -EINVAL;
+			break;
+		}
+		if (get_user(val, (int __user *)optval)) {
+			ret = -EFAULT;
+			break;
+		}
+		mroute_clean_tables(mrt, true, val);
+		break;
 	/* Control PIM assert. */
 	case MRT_ASSERT:
 		if (optlen != sizeof(val)) {
diff --git a/net/ipv6/ip6mr.c b/net/ipv6/ip6mr.c
index cc01aa3f2b5e..01f015fb33f0 100644
--- a/net/ipv6/ip6mr.c
+++ b/net/ipv6/ip6mr.c
@@ -97,7 +97,7 @@  static void mr6_netlink_event(struct mr_table *mrt, struct mfc6_cache *mfc,
 static void mrt6msg_netlink_event(struct mr_table *mrt, struct sk_buff *pkt);
 static int ip6mr_rtm_dumproute(struct sk_buff *skb,
 			       struct netlink_callback *cb);
-static void mroute_clean_tables(struct mr_table *mrt, bool all);
+static void mroute_clean_tables(struct mr_table *mrt, bool all, int flags);
 static void ipmr_expire_process(struct timer_list *t);
 
 #ifdef CONFIG_IPV6_MROUTE_MULTIPLE_TABLES
@@ -393,7 +393,7 @@  static struct mr_table *ip6mr_new_table(struct net *net, u32 id)
 static void ip6mr_free_table(struct mr_table *mrt)
 {
 	del_timer_sync(&mrt->ipmr_expire_timer);
-	mroute_clean_tables(mrt, true);
+	mroute_clean_tables(mrt, true, MRT6_FLUSH_VIFS | MRT6_FLUSH_ENTRIES);
 	rhltable_destroy(&mrt->mfc_hash);
 	kfree(mrt);
 }
@@ -1496,42 +1496,46 @@  static int ip6mr_mfc_add(struct net *net, struct mr_table *mrt,
  *	Close the multicast socket, and clear the vif tables etc
  */
 
-static void mroute_clean_tables(struct mr_table *mrt, bool all)
+static void mroute_clean_tables(struct mr_table *mrt, bool all, int flags)
 {
 	struct mr_mfc *c, *tmp;
 	LIST_HEAD(list);
 	int i;
 
 	/* Shut down all active vif entries */
-	for (i = 0; i < mrt->maxvif; i++) {
-		if (!all && (mrt->vif_table[i].flags & VIFF_STATIC))
-			continue;
-		mif6_delete(mrt, i, 0, &list);
+	if (flags & MRT6_FLUSH_VIFS) {
+		for (i = 0; i < mrt->maxvif; i++) {
+			if (!all && (mrt->vif_table[i].flags & VIFF_STATIC))
+				continue;
+			mif6_delete(mrt, i, 0, &list);
+		}
+		unregister_netdevice_many(&list);
 	}
-	unregister_netdevice_many(&list);
 
 	/* Wipe the cache */
-	list_for_each_entry_safe(c, tmp, &mrt->mfc_cache_list, list) {
-		if (!all && (c->mfc_flags & MFC_STATIC))
-			continue;
-		rhltable_remove(&mrt->mfc_hash, &c->mnode, ip6mr_rht_params);
-		list_del_rcu(&c->list);
-		call_ip6mr_mfc_entry_notifiers(read_pnet(&mrt->net),
-					       FIB_EVENT_ENTRY_DEL,
-					       (struct mfc6_cache *)c, mrt->id);
-		mr6_netlink_event(mrt, (struct mfc6_cache *)c, RTM_DELROUTE);
-		mr_cache_put(c);
-	}
+	if (flags & MRT6_FLUSH_ENTRIES) {
+		list_for_each_entry_safe(c, tmp, &mrt->mfc_cache_list, list) {
+			if (!all && (c->mfc_flags & MFC_STATIC))
+				continue;
+			rhltable_remove(&mrt->mfc_hash, &c->mnode, ip6mr_rht_params);
+			list_del_rcu(&c->list);
+			call_ip6mr_mfc_entry_notifiers(read_pnet(&mrt->net),
+										   FIB_EVENT_ENTRY_DEL,
+										   (struct mfc6_cache *)c, mrt->id);
+			mr6_netlink_event(mrt, (struct mfc6_cache *)c, RTM_DELROUTE);
+			mr_cache_put(c);
+		}
 
-	if (atomic_read(&mrt->cache_resolve_queue_len) != 0) {
-		spin_lock_bh(&mfc_unres_lock);
-		list_for_each_entry_safe(c, tmp, &mrt->mfc_unres_queue, list) {
-			list_del(&c->list);
-			mr6_netlink_event(mrt, (struct mfc6_cache *)c,
-					  RTM_DELROUTE);
-			ip6mr_destroy_unres(mrt, (struct mfc6_cache *)c);
+		if (atomic_read(&mrt->cache_resolve_queue_len) != 0) {
+			spin_lock_bh(&mfc_unres_lock);
+			list_for_each_entry_safe(c, tmp, &mrt->mfc_unres_queue, list) {
+				list_del(&c->list);
+				mr6_netlink_event(mrt, (struct mfc6_cache *)c,
+								  RTM_DELROUTE);
+				ip6mr_destroy_unres(mrt, (struct mfc6_cache *)c);
+			}
+			spin_unlock_bh(&mfc_unres_lock);
 		}
-		spin_unlock_bh(&mfc_unres_lock);
 	}
 }
 
@@ -1587,7 +1591,7 @@  int ip6mr_sk_done(struct sock *sk)
 						     NETCONFA_IFINDEX_ALL,
 						     net->ipv6.devconf_all);
 
-			mroute_clean_tables(mrt, false);
+			mroute_clean_tables(mrt, false, MRT6_FLUSH_VIFS | MRT6_FLUSH_ENTRIES);
 			err = 0;
 			break;
 		}
@@ -1703,6 +1707,20 @@  int ip6_mroute_setsockopt(struct sock *sk, int optname, char __user *optval, uns
 		rtnl_unlock();
 		return ret;
 
+	case MRT6_FLUSH:
+	{
+		int flags;
+
+		if (optlen != sizeof(flags))
+			return -EINVAL;
+		if (get_user(flags, (int __user *)optval))
+			return -EFAULT;
+		rtnl_lock();
+		mroute_clean_tables(mrt, true, flags);
+		rtnl_unlock();
+		return 0;
+	}
+
 	/*
 	 *	Control PIM assert (to activate pim will activate assert)
 	 */