2020-11-25 21:00:24

by Vladimir Oltean

[permalink] [raw]
Subject: [PATCH v3 iproute2] bridge: add support for L2 multicast groups

Extend the 'bridge mdb' command for the following syntax:
bridge mdb add dev br0 port swp0 grp 01:02:03:04:05:06 permanent

Signed-off-by: Vladimir Oltean <[email protected]>
---
Changes in v3:
- Using rt_addr_n2a_r instead of inet_ntop/ll_addr_n2a directly.
- Updated the bridge manpage.

Changes in v2:
- Removed the const void casts.
- Removed MDB_FLAGS_L2 from the UAPI to be in sync with the latest
kernel patch:
https://patchwork.ozlabs.org/project/netdev/patch/[email protected]/

bridge/mdb.c | 54 ++++++++++++++++++++++++++--------
include/uapi/linux/if_bridge.h | 1 +
man/man8/bridge.8 | 8 ++---
3 files changed, 46 insertions(+), 17 deletions(-)

diff --git a/bridge/mdb.c b/bridge/mdb.c
index 4cd7ca762b78..ef89258bc5c3 100644
--- a/bridge/mdb.c
+++ b/bridge/mdb.c
@@ -149,6 +149,7 @@ static void print_mdb_entry(FILE *f, int ifindex, const struct br_mdb_entry *e,
struct nlmsghdr *n, struct rtattr **tb)
{
const void *grp, *src;
+ const char *addr;
SPRINT_BUF(abuf);
const char *dev;
int af;
@@ -156,9 +157,16 @@ static void print_mdb_entry(FILE *f, int ifindex, const struct br_mdb_entry *e,
if (filter_vlan && e->vid != filter_vlan)
return;

- af = e->addr.proto == htons(ETH_P_IP) ? AF_INET : AF_INET6;
- grp = af == AF_INET ? (const void *)&e->addr.u.ip4 :
- (const void *)&e->addr.u.ip6;
+ if (!e->addr.proto) {
+ af = AF_PACKET;
+ grp = &e->addr.u.mac_addr;
+ } else if (e->addr.proto == htons(ETH_P_IP)) {
+ af = AF_INET;
+ grp = &e->addr.u.ip4;
+ } else {
+ af = AF_INET6;
+ grp = &e->addr.u.ip6;
+ }
dev = ll_index_to_name(ifindex);

open_json_object(NULL);
@@ -168,9 +176,14 @@ static void print_mdb_entry(FILE *f, int ifindex, const struct br_mdb_entry *e,
print_string(PRINT_ANY, "port", " port %s",
ll_index_to_name(e->ifindex));

+ /* The ETH_ALEN argument is ignored for all cases but AF_PACKET */
+ addr = rt_addr_n2a_r(af, ETH_ALEN, grp, abuf, sizeof(abuf));
+ if (!addr)
+ return;
+
print_color_string(PRINT_ANY, ifa_family_color(af),
- "grp", " grp %s",
- inet_ntop(af, grp, abuf, sizeof(abuf)));
+ "grp", " grp %s", addr);
+
if (tb && tb[MDBA_MDB_EATTR_SOURCE]) {
src = (const void *)RTA_DATA(tb[MDBA_MDB_EATTR_SOURCE]);
print_color_string(PRINT_ANY, ifa_family_color(af),
@@ -440,6 +453,25 @@ static int mdb_show(int argc, char **argv)
return 0;
}

+static int mdb_parse_grp(const char *grp, struct br_mdb_entry *e)
+{
+ if (inet_pton(AF_INET, grp, &e->addr.u.ip4)) {
+ e->addr.proto = htons(ETH_P_IP);
+ return 0;
+ }
+ if (inet_pton(AF_INET6, grp, &e->addr.u.ip6)) {
+ e->addr.proto = htons(ETH_P_IPV6);
+ return 0;
+ }
+ if (ll_addr_a2n((char *)e->addr.u.mac_addr, sizeof(e->addr.u.mac_addr),
+ grp) == ETH_ALEN) {
+ e->addr.proto = 0;
+ return 0;
+ }
+
+ return -1;
+}
+
static int mdb_modify(int cmd, int flags, int argc, char **argv)
{
struct {
@@ -497,14 +529,10 @@ static int mdb_modify(int cmd, int flags, int argc, char **argv)
if (!entry.ifindex)
return nodev(p);

- if (!inet_pton(AF_INET, grp, &entry.addr.u.ip4)) {
- if (!inet_pton(AF_INET6, grp, &entry.addr.u.ip6)) {
- fprintf(stderr, "Invalid address \"%s\"\n", grp);
- return -1;
- } else
- entry.addr.proto = htons(ETH_P_IPV6);
- } else
- entry.addr.proto = htons(ETH_P_IP);
+ if (mdb_parse_grp(grp, &entry)) {
+ fprintf(stderr, "Invalid address \"%s\"\n", grp);
+ return -1;
+ }

entry.vid = vid;
addattr_l(&req.n, sizeof(req), MDBA_SET_ENTRY, &entry, sizeof(entry));
diff --git a/include/uapi/linux/if_bridge.h b/include/uapi/linux/if_bridge.h
index 69b99901fc5a..db41a5ff34af 100644
--- a/include/uapi/linux/if_bridge.h
+++ b/include/uapi/linux/if_bridge.h
@@ -526,6 +526,7 @@ struct br_mdb_entry {
union {
__be32 ip4;
struct in6_addr ip6;
+ unsigned char mac_addr[ETH_ALEN];
} u;
__be16 proto;
} addr;
diff --git a/man/man8/bridge.8 b/man/man8/bridge.8
index 84b9b70c7dea..b3414ae31faf 100644
--- a/man/man8/bridge.8
+++ b/man/man8/bridge.8
@@ -665,7 +665,7 @@ the bridge to which this address is associated.
.SH bridge mdb - multicast group database management

.B mdb
-objects contain known IP multicast group addresses on a link.
+objects contain known IP or L2 multicast group addresses on a link.

.P
The corresponding commands display mdb entries, add new entries,
@@ -685,11 +685,11 @@ the port whose link is known to have members of this multicast group.

.TP
.BI grp " GROUP"
-the IP multicast group address whose members reside on the link connected to
-the port.
+the multicast group address (IPv4, IPv6 or L2 multicast) whose members reside
+on the link connected to the port.

.B permanent
-- the mdb entry is permanent
+- the mdb entry is permanent. Optional for IPv4 and IPv6, mandatory for L2.
.sp

.B temp
--
2.25.1


2020-11-29 21:02:56

by David Ahern

[permalink] [raw]
Subject: Re: [PATCH v3 iproute2] bridge: add support for L2 multicast groups

On 11/25/20 7:36 AM, Vladimir Oltean wrote:
> Extend the 'bridge mdb' command for the following syntax:
> bridge mdb add dev br0 port swp0 grp 01:02:03:04:05:06 permanent
>
> Signed-off-by: Vladimir Oltean <[email protected]>
> ---
> Changes in v3:
> - Using rt_addr_n2a_r instead of inet_ntop/ll_addr_n2a directly.
> - Updated the bridge manpage.
>
> Changes in v2:
> - Removed the const void casts.
> - Removed MDB_FLAGS_L2 from the UAPI to be in sync with the latest
> kernel patch:
> https://patchwork.ozlabs.org/project/netdev/patch/[email protected]/
>
> bridge/mdb.c | 54 ++++++++++++++++++++++++++--------
> include/uapi/linux/if_bridge.h | 1 +
> man/man8/bridge.8 | 8 ++---
> 3 files changed, 46 insertions(+), 17 deletions(-)
>

applied to iproute2-next