src: Support netdev egress hook

Add userspace support for the netdev egress hook which is queued up for
v5.16-rc1, complete with documentation and tests.  Usage is identical to
the ingress hook.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

3 files changed, 24 insertions, 1 deletions

diff --git a/tests/shell/testcases/chains/0021prio_0 b/tests/shell/testcases/chains/0021prio_0
index e7612974..d450dc0b 100755
--- a/tests/shell/testcases/chains/0021prio_0
+++ b/tests/shell/testcases/chains/0021prio_0
@@ -69,6 +69,7 @@ done
 family=netdev
 echo "add table $family x"
 gen_chains $family ingress filter lo
+gen_chains $family egress filter lo
 
 family=bridge
 echo "add table $family x"
diff --git a/tests/shell/testcases/chains/0026prio_netdev_1 b/tests/shell/testcases/chains/0026prio_netdev_1
index aa902e9b..b6fa3db5 100755
--- a/tests/shell/testcases/chains/0026prio_netdev_1
+++ b/tests/shell/testcases/chains/0026prio_netdev_1
@@ -1,7 +1,8 @@
 #!/bin/bash
 
 family=netdev
-	hook=ingress
+	for hook in ingress egress
+	do
 		for prioname in raw mangle dstnat security srcnat
 		do
 			$NFT add table $family x || exit 1
@@ -12,4 +13,5 @@ family=netdev
 				exit 1
 			fi
 		done
+	done
 exit 0
diff --git a/tests/shell/testcases/chains/dumps/0021prio_0.nft b/tests/shell/testcases/chains/dumps/0021prio_0.nft
index ca94d441..4297d246 100644
--- a/tests/shell/testcases/chains/dumps/0021prio_0.nft
+++ b/tests/shell/testcases/chains/dumps/0021prio_0.nft
@@ -1382,6 +1382,26 @@ table netdev x {
 	chain ingressfilterp11 {
 		type filter hook ingress device "lo" priority 11; policy accept;
 	}
+
+	chain egressfilterm11 {
+		type filter hook egress device "lo" priority -11; policy accept;
+	}
+
+	chain egressfilterm10 {
+		type filter hook egress device "lo" priority filter - 10; policy accept;
+	}
+
+	chain egressfilter {
+		type filter hook egress device "lo" priority filter; policy accept;
+	}
+
+	chain egressfilterp10 {
+		type filter hook egress device "lo" priority filter + 10; policy accept;
+	}
+
+	chain egressfilterp11 {
+		type filter hook egress device "lo" priority 11; policy accept;
+	}
 }
 table bridge x {
 	chain preroutingfilterm11 {