From 9b8515f71bd413520ba7d8e2b92a60deb2c7a528 Mon Sep 17 00:00:00 2001
From: Mike Karels <karels@FreeBSD.org>
Date: Tue, 28 Nov 2023 13:47:37 -0600
Subject: [PATCH] ifconfig: add -D option to print driver name for interface

Add -D option to add the drivername and unit number to ifconfig output
for normal display, including -a.  Use ifconfig_get_orig_name() from
libifconfig to fetch the name.  Note that this is the original name
for many drivers, but not for some exceptions like epair (which appends
'a' or 'b' to the unit number).  epair interface pairs both display
as "epair0", etc.  Make -v imply -D; might as well be fully verbose.

Reviewed by:	zlei, kp
Differential Revision:	https://reviews.freebsd.org/D42721

(cherry picked from commit cd201c090858e5cfae3be005453ec634c1fca36a)
---
 sbin/ifconfig/ifconfig.8         | 10 ++++++++--
 sbin/ifconfig/ifconfig.c         |  5 ++++-
 sbin/ifconfig/ifconfig.h         |  1 +
 sbin/ifconfig/ifconfig_netlink.c | 17 +++++++++++++++++
 4 files changed, 30 insertions(+), 3 deletions(-)

diff --git a/sbin/ifconfig/ifconfig.8 b/sbin/ifconfig/ifconfig.8
index 3b1774606b2..a538981608c 100644
--- a/sbin/ifconfig/ifconfig.8
+++ b/sbin/ifconfig/ifconfig.8
@@ -36,7 +36,7 @@
 .Sh SYNOPSIS
 .Nm
 .Op Fl j Ar jail
-.Op Fl kLmn
+.Op Fl DkLmn
 .Op Fl f Ar type Ns Cm \&: Ns Ar format
 .Ar interface
 .Op Cm create
@@ -55,7 +55,7 @@
 .Nm
 .Op Fl j Ar jail
 .Fl a
-.Op Fl dkLmuv
+.Op Fl dDkLmuv
 .Op Fl f Ar type Ns Cm \&: Ns Ar format
 .Op Fl G Ar groupname
 .Op Fl g Ar groupname
@@ -104,6 +104,12 @@ with no additional information.
 Use of this flag is mutually exclusive with all other flags and commands.
 .It Fl d
 Display only the interfaces that are down.
+.It Fl D
+Include the driver name and unit number of the interface in the output.
+This is normally the original name of the interface,
+even if it has been renamed; it may differ from the original name
+in some cases, such as
+.Xr epair 4 .
 .It Fl f Xo
 .Ar type Ns Cm \&: Ns Ar format Ns
 .Op Cm \&, Ns Ar type Ns Cm \&: Ns Ar format Ar ...
diff --git a/sbin/ifconfig/ifconfig.c b/sbin/ifconfig/ifconfig.c
index 1a7823fedd6..7a78e9a934f 100644
--- a/sbin/ifconfig/ifconfig.c
+++ b/sbin/ifconfig/ifconfig.c
@@ -465,7 +465,7 @@ args_parse(struct ifconfig_args *args, int argc, char *argv[])
 	int c;
 
 	/* Parse leading line options */
-	strlcpy(options, "G:adf:j:klmnuv", sizeof(options));
+	strlcpy(options, "G:adDf:j:klmnuv", sizeof(options));
 	for (p = opts; p != NULL; p = p->next)
 		strlcat(options, p->opt, sizeof(options));
 	while ((c = getopt(argc, argv, options)) != -1) {
@@ -476,6 +476,9 @@ args_parse(struct ifconfig_args *args, int argc, char *argv[])
 		case 'd':	/* restrict scan to "down" interfaces */
 			args->downonly = true;
 			break;
+		case 'D':	/* Print driver name */
+			args->drivername = true;
+			break;
 		case 'f':
 			if (optarg == NULL)
 				usage();
diff --git a/sbin/ifconfig/ifconfig.h b/sbin/ifconfig/ifconfig.h
index 80e6b9bc228..0ae317aca40 100644
--- a/sbin/ifconfig/ifconfig.h
+++ b/sbin/ifconfig/ifconfig.h
@@ -230,6 +230,7 @@ struct ifconfig_args {
 	bool supmedia;		/* Supported media */
 	bool printkeys;		/* Print security keys */
 	bool allfamilies;	/* Print all families */
+	bool drivername;	/* Print driver name */
 	int verbose;		/* verbosity level */
 	int argc;
 	char **argv;
diff --git a/sbin/ifconfig/ifconfig_netlink.c b/sbin/ifconfig/ifconfig_netlink.c
index 7be340e18ab..bb0d242f21f 100644
--- a/sbin/ifconfig/ifconfig_netlink.c
+++ b/sbin/ifconfig/ifconfig_netlink.c
@@ -369,6 +369,7 @@ status_nl(if_ctx *ctx, struct iface *iface)
 {
 	if_link_t *link = &iface->link;
 	struct ifconfig_args *args = ctx->args;
+	char *drivername = NULL;
 
 	printf("%s: ", link->ifla_ifname);
 
@@ -413,6 +414,22 @@ status_nl(if_ctx *ctx, struct iface *iface)
 		args->afp->af_other_status(ctx);
 
 	print_ifstatus(ctx);
+	if (args->drivername || args->verbose) {
+		if (ifconfig_get_orig_name(lifh, link->ifla_ifname,
+		    &drivername) != 0) {
+			if (ifconfig_err_errtype(lifh) == OTHER)
+				fprintf(stderr, "get original name: %s\n",
+				    strerror(ifconfig_err_errno(lifh)));
+			else
+				fprintf(stderr,
+				    "get original name: error type %d\n",
+				    ifconfig_err_errtype(lifh));
+			exit_code = 1;
+		}
+		if (drivername != NULL)
+			printf("\tdrivername: %s\n", drivername);
+		free(drivername);
+	}
 	if (args->verbose > 0)
 		sfp_status(ctx);
 }