[PATCH iproute2] ip: link: netkit: Support scrub options

[Jordan Rife <jordan@xxxxxxxx>]

Add "scrub" option to configure IFLA_NETKIT_SCRUB and
IFLA_NETKIT_PEER_SCRUB when setting up a link. Add "scrub" and
"peer scrub" to device details as well when printing.

$ sudo ./ip/ip link add jordan type netkit scrub default peer scrub none
$ ./ip/ip -details link show jordan
43: jordan@nk0: <BROADCAST,MULTICAST,NOARP,M-DOWN> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
    link/ether 00:00:00:00:00:00 brd ff:ff:ff:ff:ff:ff promiscuity 0 allmulti 0 minmtu 68 maxmtu 65535
    netkit mode l3 type primary policy forward peer policy forward scrub default peer scrub none numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535 tso_max_size 524280 tso_max_segs 65535 gro_max_size 65536 gso_ipv4_max_size 65536 gro_ipv4_max_size 65536

Link: https://lore.kernel.org/netdev/20241004101335.117711-1-daniel@xxxxxxxxxxxxx/

Signed-off-by: Jordan Rife <jordan@xxxxxxxx>
---
 ip/iplink_netkit.c | 46 +++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 45 insertions(+), 1 deletion(-)

diff --git a/ip/iplink_netkit.c b/ip/iplink_netkit.c
index 49550a2e..f2c6e699 100644
--- a/ip/iplink_netkit.c
+++ b/ip/iplink_netkit.c
@@ -24,13 +24,19 @@ static const char * const netkit_policy_strings[] = {
 	[NETKIT_DROP]		= "blackhole",
 };
 
+static const char * const netkit_scrub_strings[] = {
+	[NETKIT_SCRUB_NONE]	= "none",
+	[NETKIT_SCRUB_DEFAULT]	= "default",
+};
+
 static void explain(struct link_util *lu, FILE *f)
 {
 	fprintf(f,
-		"Usage: ... %s [ mode MODE ] [ POLICY ] [ peer [ POLICY <options> ] ]\n"
+		"Usage: ... %s [ mode MODE ] [ POLICY ] [scrub SCRUB] [ peer [ POLICY <options> ] ]\n"
 		"\n"
 		"MODE: l3 | l2\n"
 		"POLICY: forward | blackhole\n"
+		"SCRUB: default | none\n"
 		"(first values are the defaults if nothing is specified)\n"
 		"\n"
 		"To get <options> type 'ip link add help'.\n",
@@ -91,6 +97,23 @@ static int netkit_parse_opt(struct link_util *lu, int argc, char **argv,
 			if (seen_peer)
 				duparg("peer", *(argv + 1));
 			seen_peer = true;
+		} else if (strcmp(*argv, "scrub") == 0) {
+			int attr_name = seen_peer ?
+					IFLA_NETKIT_PEER_SCRUB :
+					IFLA_NETKIT_SCRUB;
+			enum netkit_scrub scrub;
+
+			NEXT_ARG();
+
+			if (strcmp(*argv, "none") == 0) {
+				scrub = NETKIT_SCRUB_NONE;
+			} else if (strcmp(*argv, "default") == 0) {
+				scrub = NETKIT_SCRUB_DEFAULT;
+			} else {
+				fprintf(stderr, "Error: scrub must be either \"none\" or \"default\"\n");
+				return -1;
+			}
+			addattr32(n, 1024, attr_name, scrub);
 		} else {
 			char *type = NULL;
 
@@ -144,6 +167,15 @@ static const char *netkit_print_mode(__u32 mode)
 	return netkit_mode_strings[mode] ? : inv;
 }
 
+static const char *netkit_print_scrub(enum netkit_scrub scrub)
+{
+	const char *inv = "UNKNOWN";
+
+	if (scrub >= ARRAY_SIZE(netkit_scrub_strings))
+		return inv;
+	return netkit_scrub_strings[scrub] ? : inv;
+}
+
 static void netkit_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[])
 {
 	if (!tb)
@@ -172,6 +204,18 @@ static void netkit_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[])
 		print_string(PRINT_ANY, "peer_policy", "peer policy %s ",
 			     netkit_print_policy(policy));
 	}
+	if (tb[IFLA_NETKIT_SCRUB]) {
+		enum netkit_scrub scrub = rta_getattr_u32(tb[IFLA_NETKIT_SCRUB]);
+
+		print_string(PRINT_ANY, "scrub", "scrub %s ",
+			     netkit_print_scrub(scrub));
+	}
+	if (tb[IFLA_NETKIT_PEER_SCRUB]) {
+		enum netkit_scrub scrub = rta_getattr_u32(tb[IFLA_NETKIT_PEER_SCRUB]);
+
+		print_string(PRINT_ANY, "peer_scrub", "peer scrub %s ",
+			     netkit_print_scrub(scrub));
+	}
 }
 
 static void netkit_print_help(struct link_util *lu,
-- 
2.43.0