[PATCH v2 iproute2-next 4/4] bridge: fdb: enable FDB blackhole feature
From: Hans Schultz <hidden>
Date: 2022-10-04 15:21:15
Also in:
bridge, linux-arm-kernel, linux-kselftest, linux-mediatek, lkml
Subsystem:
the rest · Maintainer:
Linus Torvalds
Block traffic to a specific host with the command:
bridge fdb add <MAC> vlan <vid> dev br0 blackhole
Blackhole FDB entries can be added, deleted and replaced with
ordinary FDB entries.
Example with output:
$ bridge fdb add 10:10:10:10:10:10 dev br0 blackhole
$ bridge -d fdb show dev br0
10:10:10:10:10:10 vlan 1 blackhole master br0 permanent
10:10:10:10:10:10 blackhole master br0 permanent
$ bridge -d -j -p fdb show dev br0
[ {
"mac": "10:10:10:10:10:10",
"vlan": 1,
"flags": [ "blackhole" ],
"master": "br0",
"state": "permanent"
},{
"mac": "10:10:10:10:10:10",
"flags": [ "blackhole" ],
"master": "br0",
"state": "permanent"
} ]
Signed-off-by: Hans Schultz <redacted>
---
bridge/fdb.c | 13 ++++++++++++-
man/man8/bridge.8 | 12 ++++++++++++
2 files changed, 24 insertions(+), 1 deletion(-)
diff --git a/bridge/fdb.c b/bridge/fdb.c
index f1f0a5bb..1c8c50a8 100644
--- a/bridge/fdb.c
+++ b/bridge/fdb.c@@ -38,7 +38,7 @@ static void usage(void) fprintf(stderr, "Usage: bridge fdb { add | append | del | replace } ADDR dev DEV\n" " [ self ] [ master ] [ use ] [ router ] [ extern_learn ]\n" - " [ sticky ] [ local | static | dynamic ] [ vlan VID ]\n" + " [ sticky ] [ local | static | dynamic ] [ blackhole ] [ vlan VID ]\n" " { [ dst IPADDR ] [ port PORT] [ vni VNI ] | [ nhid NHID ] }\n" " [ via DEV ] [ src_vni VNI ]\n" " bridge fdb [ show [ br BRDEV ] [ brport DEV ] [ vlan VID ]\n"
@@ -116,6 +116,9 @@ static void fdb_print_flags(FILE *fp, unsigned int flags, __u8 ext_flags) if (flags & NTF_STICKY) print_string(PRINT_ANY, NULL, "%s ", "sticky"); + if (ext_flags & NTF_EXT_BLACKHOLE) + print_string(PRINT_ANY, NULL, "%s ", "blackhole"); + if (ext_flags & NTF_EXT_LOCKED) print_string(PRINT_ANY, NULL, "%s ", "locked");
@@ -421,6 +424,7 @@ static int fdb_modify(int cmd, int flags, int argc, char **argv) char *endptr; short vid = -1; __u32 nhid = 0; + __u32 ext_flags = 0; while (argc > 0) { if (strcmp(*argv, "dev") == 0) {
@@ -492,6 +496,8 @@ static int fdb_modify(int cmd, int flags, int argc, char **argv) req.ndm.ndm_flags |= NTF_EXT_LEARNED; } else if (matches(*argv, "sticky") == 0) { req.ndm.ndm_flags |= NTF_STICKY; + } else if (matches(*argv, "blackhole") == 0) { + ext_flags |= NTF_EXT_BLACKHOLE; } else { if (strcmp(*argv, "to") == 0) NEXT_ARG();
@@ -534,6 +540,11 @@ static int fdb_modify(int cmd, int flags, int argc, char **argv) if (dst_ok) addattr_l(&req.n, sizeof(req), NDA_DST, &dst.data, dst.bytelen); + if (ext_flags && + addattr_l(&req.n, sizeof(req), NDA_FLAGS_EXT, &ext_flags, + sizeof(ext_flags)) < 0) + return -1; + if (vid >= 0) addattr16(&req.n, sizeof(req), NDA_VLAN, vid); if (nhid > 0)
diff --git a/man/man8/bridge.8 b/man/man8/bridge.8
index f4f1d807..0119a2a9 100644
--- a/man/man8/bridge.8
+++ b/man/man8/bridge.8@@ -85,6 +85,13 @@ bridge \- show / manipulate bridge addresses and devices .B nhid .IR NHID " } " +.ti -8 +.BR "bridge fdb" " { " add " | " del " } " +.I LLADR +.B dev +.IR BRDEV " [ " +.BR self " ] [ " local " ] [ " blackhole " ] " + .ti -8 .BR "bridge fdb" " [ [ " show " ] [ " .B br
@@ -701,6 +708,11 @@ controller learnt dynamic entry. Kernel will not age such an entry. - this entry will not change its port due to learning. .sp +.B blackhole +- this entry will silently discard all matching packets. The entry must +be added as a local permanent entry. +.sp + .in -8 The next command line parameters apply only when the specified device
--
2.34.1