[PATCH iproute2 net-next 0/2] Extend ip address command to enable multicast group join/leave on IP level

[PATCH iproute2 net-next 0/2] Extend ip address command to enable multicast group join/leave on IP level

[Madhu Challa]

Extends "ip address" command with autojoin keyword

Madhu Challa (2):
  Header rebase for IFA_F_MCAUTOJOIN
  Enable configuring multicast group join / leave at IP level.

 include/linux/if_addr.h |  1 +
 ip/ipaddress.c          | 26 +++++++++++++++++++++++++-
 2 files changed, 26 insertions(+), 1 deletion(-)

-- 
1.9.1

[PATCH iproute2 net-next 1/2] Header rebase for IFA_F_MCAUTOJOIN

[Madhu Challa]

---
 include/linux/if_addr.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/include/linux/if_addr.h b/include/linux/if_addr.h
index cc375e4..2033adc 100644
--- a/include/linux/if_addr.h
+++ b/include/linux/if_addr.h
@@ -50,6 +50,7 @@ enum {
 #define IFA_F_PERMANENT		0x80
 #define IFA_F_MANAGETEMPADDR	0x100
 #define IFA_F_NOPREFIXROUTE	0x200
+#define IFA_F_MCAUTOJOIN	0x400
 
 struct ifa_cacheinfo {
 	__u32	ifa_prefered;
-- 
1.9.1

Re: [PATCH iproute2 net-next 1/2] Header rebase for IFA_F_MCAUTOJOIN

[Stephen Hemminger]

On Wed,  4 Mar 2015 10:30:09 -0800
Madhu Challa <challa@noironetworks.com> wrote:

> ---
>  include/linux/if_addr.h | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/include/linux/if_addr.h b/include/linux/if_addr.h
> index cc375e4..2033adc 100644
> --- a/include/linux/if_addr.h
> +++ b/include/linux/if_addr.h
> @@ -50,6 +50,7 @@ enum {
>  #define IFA_F_PERMANENT		0x80
>  #define IFA_F_MANAGETEMPADDR	0x100
>  #define IFA_F_NOPREFIXROUTE	0x200
> +#define IFA_F_MCAUTOJOIN	0x400
>  
>  struct ifa_cacheinfo {
>  	__u32	ifa_prefered;

Already picked this up in my net-next branch.

[PATCH iproute2 net-next 2/2] Enable configuring multicast group join / leave at IP level.

[Madhu Challa]

Joining multicast group on ethernet level via "ip maddr" command would
not work if we have an Ethernet switch that does igmp snooping since
the switch would not replicate multicast packets on ports that did not
have IGMP reports for the multicast addresses.

Linux vxlan interfaces created via "ip link add vxlan" have the group option
that enables then to do the required join.

By extending ip address command with option "autojoin" we can get similar
functionality for openvswitch vxlan interfaces as well as other tunneling
mechanisms that need to receive multicast traffic.

example:
ip address add 224.1.1.10/24 dev eth5 autojoin
ip address del 224.1.1.10/24 dev eth5
---
 ip/ipaddress.c | 26 +++++++++++++++++++++++++-
 1 file changed, 25 insertions(+), 1 deletion(-)

diff --git a/ip/ipaddress.c b/ip/ipaddress.c
index 99a6ab5..e582da0 100644
--- a/ip/ipaddress.c
+++ b/ip/ipaddress.c
@@ -85,7 +85,7 @@ static void usage(void)
 	fprintf(stderr, "           [-]tentative | [-]deprecated | [-]dadfailed | temporary |\n");
 	fprintf(stderr, "           CONFFLAG-LIST ]\n");
 	fprintf(stderr, "CONFFLAG-LIST := [ CONFFLAG-LIST ] CONFFLAG\n");
-	fprintf(stderr, "CONFFLAG  := [ home | nodad | mngtmpaddr | noprefixroute ]\n");
+	fprintf(stderr, "CONFFLAG  := [ home | nodad | mngtmpaddr | noprefixroute | autojoin ]\n");
 	fprintf(stderr, "LIFETIME := [ valid_lft LFT ] [ preferred_lft LFT ]\n");
 	fprintf(stderr, "LFT := forever | SECONDS\n");
 
@@ -915,6 +915,10 @@ int print_addrinfo(const struct sockaddr_nl *who, struct nlmsghdr *n,
 		ifa_flags &= ~IFA_F_NOPREFIXROUTE;
 		fprintf(fp, "noprefixroute ");
 	}
+	if (ifa_flags & IFA_F_MCAUTOJOIN) {
+		ifa_flags &= ~IFA_F_MCAUTOJOIN;
+		fprintf(fp, "autojoin ");
+	}
 	if (!(ifa_flags & IFA_F_PERMANENT)) {
 		fprintf(fp, "dynamic ");
 	} else
@@ -1354,6 +1358,9 @@ static int ipaddr_list_flush_or_save(int argc, char **argv, int action)
 		} else if (strcmp(*argv, "noprefixroute") == 0) {
 			filter.flags |= IFA_F_NOPREFIXROUTE;
 			filter.flagmask |= IFA_F_NOPREFIXROUTE;
+		} else if (strcmp(*argv, "autojoin") == 0) {
+			filter.flags |= IFA_F_MCAUTOJOIN;
+			filter.flagmask |= IFA_F_MCAUTOJOIN;
 		} else if (strcmp(*argv, "dadfailed") == 0) {
 			filter.flags |= IFA_F_DADFAILED;
 			filter.flagmask |= IFA_F_DADFAILED;
@@ -1558,6 +1565,16 @@ static int default_scope(inet_prefix *lcl)
 	return 0;
 }
 
+static bool ipaddr_is_multicast(inet_prefix *a)
+{
+	if (a->family == AF_INET)
+		return IN_MULTICAST(ntohl(a->data[0]));
+	else if (a->family == AF_INET6)
+		return IN6_IS_ADDR_MULTICAST(a->data);
+	else
+		return false;
+}
+
 static int ipaddr_modify(int cmd, int flags, int argc, char **argv)
 {
 	struct {
@@ -1665,6 +1682,8 @@ static int ipaddr_modify(int cmd, int flags, int argc, char **argv)
 			ifa_flags |= IFA_F_MANAGETEMPADDR;
 		} else if (strcmp(*argv, "noprefixroute") == 0) {
 			ifa_flags |= IFA_F_NOPREFIXROUTE;
+		} else if (strcmp(*argv, "autojoin") == 0) {
+			ifa_flags |= IFA_F_MCAUTOJOIN;
 		} else {
 			if (strcmp(*argv, "local") == 0) {
 				NEXT_ARG();
@@ -1755,6 +1774,11 @@ static int ipaddr_modify(int cmd, int flags, int argc, char **argv)
 			  sizeof(cinfo));
 	}
 
+	if ((ifa_flags & IFA_F_MCAUTOJOIN) && !ipaddr_is_multicast(&lcl)) {
+		fprintf(stderr, "autojoin needs multicast address\n");
+		return -1;
+	}
+
 	if (rtnl_talk(&rth, &req.n, 0, 0, NULL) < 0)
 		return -2;
 
-- 
1.9.1

Re: [PATCH iproute2 net-next 2/2] Enable configuring multicast group join / leave at IP level.

[Stephen Hemminger]

On Wed,  4 Mar 2015 10:30:10 -0800
Madhu Challa <challa@noironetworks.com> wrote:

> Joining multicast group on ethernet level via "ip maddr" command would
> not work if we have an Ethernet switch that does igmp snooping since
> the switch would not replicate multicast packets on ports that did not
> have IGMP reports for the multicast addresses.
> 
> Linux vxlan interfaces created via "ip link add vxlan" have the group option
> that enables then to do the required join.
> 
> By extending ip address command with option "autojoin" we can get similar
> functionality for openvswitch vxlan interfaces as well as other tunneling
> mechanisms that need to receive multicast traffic.
> 
> example:
> ip address add 224.1.1.10/24 dev eth5 autojoin
> ip address del 224.1.1.10/24 dev eth5

Applied, but please update manual pages as well.

Re: [PATCH iproute2 net-next 2/2] Enable configuring multicast group join / leave at IP level.

[Madhu Challa]

On Sun, Mar 15, 2015 at 12:43 PM, Stephen Hemminger
<stephen@networkplumber.org> wrote:
> On Wed,  4 Mar 2015 10:30:10 -0800
> Madhu Challa <challa@noironetworks.com> wrote:
>
>> Joining multicast group on ethernet level via "ip maddr" command would
>> not work if we have an Ethernet switch that does igmp snooping since
>> the switch would not replicate multicast packets on ports that did not
>> have IGMP reports for the multicast addresses.
>>
>> Linux vxlan interfaces created via "ip link add vxlan" have the group option
>> that enables then to do the required join.
>>
>> By extending ip address command with option "autojoin" we can get similar
>> functionality for openvswitch vxlan interfaces as well as other tunneling
>> mechanisms that need to receive multicast traffic.
>>
>> example:
>> ip address add 224.1.1.10/24 dev eth5 autojoin
>> ip address del 224.1.1.10/24 dev eth5
>
> Applied, but please update manual pages as well.

Thanks Stephen. Sure I will.

Thanks.