[PATCH main v2 1/3] macsec: add option to pass flag list to ip link add command

[<ehakim@nvidia.com>]

From: Emeel Hakim <ehakim@nvidia.com>

This patch introduces a new flag list option to ip link add
command using type macsec, the patch prepares a framework for
passing and parsing flag list for future features like macsec
extended packet number (XPN) to use.

Signed-off-by: Emeel Hakim <ehakim@nvidia.com>
---
 ip/ipmacsec.c | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/ip/ipmacsec.c b/ip/ipmacsec.c
index bf48e8b5..9aeaafcc 100644
--- a/ip/ipmacsec.c
+++ b/ip/ipmacsec.c
@@ -1256,9 +1256,28 @@ static void usage(FILE *f)
 		"                  [ validate { strict | check | disabled } ]\n"
 		"                  [ encodingsa { 0..3 } ]\n"
 		"                  [ offload { mac | phy | off } ]\n"
+		"                  [ flag FLAG-LIST ]\n"
+		"FLAG-LIST :=      [ FLAG-LIST ] FLAG\n"
+		"FLAG :=\n"
 		);
 }
 
+static int macsec_flag_parse(__u8 *flags, int *argcp, char ***argvp)
+{
+	int argc = *argcp;
+	char **argv = *argvp;
+
+	while (1) {
+		/* parse flag list */
+		break;
+	}
+
+	*argcp = argc;
+	*argvp = argv;
+
+	return 0;
+}
+
 static int macsec_parse_opt(struct link_util *lu, int argc, char **argv,
 			    struct nlmsghdr *n)
 {
@@ -1271,6 +1290,7 @@ static int macsec_parse_opt(struct link_util *lu, int argc, char **argv,
 	bool es = false, scb = false, send_sci = false;
 	int replay_protect = -1;
 	struct sci sci = { 0 };
+	__u8 flags = 0;
 
 	ret = get_sci_portaddr(&sci, &argc, &argv, true, true);
 	if (ret < 0) {
@@ -1388,6 +1408,9 @@ static int macsec_parse_opt(struct link_util *lu, int argc, char **argv,
 				return ret;
 			addattr8(n, MACSEC_BUFLEN,
 				 IFLA_MACSEC_OFFLOAD, offload);
+		} else if (strcmp(*argv, "flag") == 0) {
+			NEXT_ARG();
+			macsec_flag_parse(&flags, &argc, &argv);
 		} else {
 			fprintf(stderr, "macsec: unknown command \"%s\"?\n",
 				*argv);
-- 
2.21.3