[patch iproute2-next v4 3/3] ip: allow to use alternative names as handle

[Jiri Pirko <jiri@resnulli.us>]

From: Jiri Pirko <jiri@mellanox.com>

Extend ll_name_to_index() to get the index of a netdevice using
alternative interface name. Allow alternative long names to pass checks
in couple of ip link/addr commands.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
---
v3->v4:
- moved utils.h include into the first patch
v2->v3:
- removed altnametoindex and doing IFLA_IFNAME/IFLA_ALT_IFNAME in
  ll_link_get() instead.
rfc->v1:
- added patch description
---
 ip/iplink.c  | 5 +++--
 lib/ll_map.c | 7 ++++---
 2 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/ip/iplink.c b/ip/iplink.c
index bf90fad1b3ea..47f73988c2d5 100644
--- a/ip/iplink.c
+++ b/ip/iplink.c
@@ -931,7 +931,7 @@ int iplink_parse(int argc, char **argv, struct iplink_req *req, char **type)
 				NEXT_ARG();
 			if (dev != name)
 				duparg2("dev", *argv);
-			if (check_ifname(*argv))
+			if (check_altifname(*argv))
 				invarg("\"dev\" not a valid ifname", *argv);
 			dev = *argv;
 		}
@@ -1106,7 +1106,8 @@ int iplink_get(char *name, __u32 filt_mask)
 
 	if (name) {
 		addattr_l(&req.n, sizeof(req),
-			  IFLA_IFNAME, name, strlen(name) + 1);
+			  !check_ifname(name) ? IFLA_IFNAME : IFLA_ALT_IFNAME,
+			  name, strlen(name) + 1);
 	}
 	addattr32(&req.n, sizeof(req), IFLA_EXT_MASK, filt_mask);
 
diff --git a/lib/ll_map.c b/lib/ll_map.c
index 1b382b5cec94..52d149dcd91b 100644
--- a/lib/ll_map.c
+++ b/lib/ll_map.c
@@ -72,7 +72,7 @@ static struct ll_cache *ll_get_by_name(const char *name)
 		struct ll_cache *im
 			= container_of(n, struct ll_cache, name_hash);
 
-		if (strncmp(im->name, name, IFNAMSIZ) == 0)
+		if (strcmp(im->name, name) == 0)
 			return im;
 	}
 
@@ -287,8 +287,9 @@ static int ll_link_get(const char *name, int index)
 
 	addattr32(&req.n, sizeof(req), IFLA_EXT_MASK, filt_mask);
 	if (name)
-		addattr_l(&req.n, sizeof(req), IFLA_IFNAME, name,
-			  strlen(name) + 1);
+		addattr_l(&req.n, sizeof(req),
+			  !check_ifname(name) ? IFLA_IFNAME : IFLA_ALT_IFNAME,
+			  name, strlen(name) + 1);
 
 	if (rtnl_talk_suppress_rtnl_errmsg(&rth, &req.n, &answer) < 0)
 		goto out;
-- 
2.21.0