Add support for wireguard peer descriptions

"wgdescr[iption] foo" to label one peer (amongst many) on a wg(4) interface,
"-wgdescr[iption]" or "wgdescr ''" to remove the label, completely analogous
to existing interface discriptions.

Idea/initial diff from Mikolaj Kucharski (OK sthen)
Tests/prodded by Hrvoje Popovski
Tweaks/manual bits from me
Feedback deraadt sthen mvs claudio
OK claudio

2 files changed, 39 insertions, 4 deletions

diff --git a/sbin/ifconfig/ifconfig.8 b/sbin/ifconfig/ifconfig.8
index c635ede8b4d..3f03ddf6d9d 100644
--- a/sbin/ifconfig/ifconfig.8
+++ b/sbin/ifconfig/ifconfig.8
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: ifconfig.8,v 1.395 2023/05/16 14:32:54 jan Exp $
+.\"	$OpenBSD: ifconfig.8,v 1.396 2023/06/01 18:57:53 kn Exp $
 .\"	$NetBSD: ifconfig.8,v 1.11 1996/01/04 21:27:29 pk Exp $
 .\"     $FreeBSD: ifconfig.8,v 1.16 1998/02/01 07:03:29 steve Exp $
 .\"
@@ -31,7 +31,7 @@
 .\"
 .\"     @(#)ifconfig.8	8.4 (Berkeley) 6/1/94
 .\"
-.Dd $Mdocdate: May 16 2023 $
+.Dd $Mdocdate: June 1 2023 $
 .Dt IFCONFIG 8
 .Os
 .Sh NAME
@@ -2316,6 +2316,7 @@ Packets on a VLAN interface without a tag set will use a value of
 .Op Fl wgpeerall
 .Oo
 .Oo Fl Oc Ns Cm wgpeer Ar publickey
+.Op Oo Fl Oc Ns Cm wgdescr Ns Oo Cm iption Oc Ar value
 .Op Cm wgaip Ar allowed-ip_address/prefix
 .Op Cm wgendpoint Ar peer_address port
 .Op Cm wgpka Ar interval
@@ -2383,6 +2384,13 @@ Peer configuration options, which apply to the
 immediately preceding them,
 are as follows:
 .Bl -tag -width Ds
+.Tg wgdescription
+.It Cm wgdescr Ns Oo Cm iption Oc Ar value
+Set the peer's description.
+This can be used to label peers in situations where they may
+otherwise be difficult to distinguish.
+.It Cm -wgdescr Ns Op Cm iption
+Clear the peer description.
 .It Cm wgaip Ar allowed-ip_address/prefix
 Set the peer's IPv4 or IPv6
 .Ar allowed-ip_address
diff --git a/sbin/ifconfig/ifconfig.c b/sbin/ifconfig/ifconfig.c
index 5dc9ea641ca..1ae9a90bb82 100644
--- a/sbin/ifconfig/ifconfig.c
+++ b/sbin/ifconfig/ifconfig.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ifconfig.c,v 1.464 2023/05/16 14:32:54 jan Exp $	*/
+/*	$OpenBSD: ifconfig.c,v 1.465 2023/06/01 18:57:54 kn Exp $	*/
 /*	$NetBSD: ifconfig.c,v 1.40 1997/10/01 02:19:43 enami Exp $	*/
 
 /*
@@ -351,6 +351,7 @@ void	transceiverdump(const char *, int);
 
 /* WG */
 void	setwgpeer(const char *, int);
+void	setwgpeerdesc(const char *, int);
 void	setwgpeerep(const char *, const char *);
 void	setwgpeeraip(const char *, int);
 void	setwgpeerpsk(const char *, int);
@@ -360,6 +361,7 @@ void	setwgkey(const char *, int);
 void	setwgrtable(const char *, int);
 
 void	unsetwgpeer(const char *, int);
+void	unsetwgpeerdesc(const char *, int);
 void	unsetwgpeerpsk(const char *, int);
 void	unsetwgpeerall(const char *, int);
 
@@ -619,6 +621,8 @@ const struct	cmd {
 	{ "sffdump",	0,		0,		transceiverdump },
 
 	{ "wgpeer",	NEXTARG,	A_WIREGUARD,	setwgpeer},
+	{ "wgdescription", NEXTARG,	A_WIREGUARD,	setwgpeerdesc},
+	{ "wgdescr",	NEXTARG,	A_WIREGUARD,	setwgpeerdesc},
 	{ "wgendpoint",	NEXTARG2,	A_WIREGUARD,	NULL,	setwgpeerep},
 	{ "wgaip",	NEXTARG,	A_WIREGUARD,	setwgpeeraip},
 	{ "wgpsk",	NEXTARG,	A_WIREGUARD,	setwgpeerpsk},
@@ -627,7 +631,8 @@ const struct	cmd {
 	{ "wgkey",	NEXTARG,	A_WIREGUARD,	setwgkey},
 	{ "wgrtable",	NEXTARG,	A_WIREGUARD,	setwgrtable},
 	{ "-wgpeer",	NEXTARG,	A_WIREGUARD,	unsetwgpeer},
-	{ "-wgpsk",	0,		A_WIREGUARD,	unsetwgpeerpsk},
+	{ "-wgdescription", 0,		A_WIREGUARD,	unsetwgpeerdesc},
+	{ "-wgdescr",	0,		A_WIREGUARD,	unsetwgpeerdesc},
 	{ "-wgpeerall",	0,		A_WIREGUARD,	unsetwgpeerall},
 
 #else /* SMALL */
@@ -5736,6 +5741,15 @@ setwgpeer(const char *peerkey_b64, int param)
 }
 
 void
+setwgpeerdesc(const char *descr, int param)
+{
+	if (wg_peer == NULL)
+		errx(1, "wgdescr: wgpeer not set");
+	wg_peer->p_flags |= WG_PEER_SET_DESCRIPTION;
+	strlcpy(wg_peer->p_description, descr, IFDESCRSIZE);
+}
+
+void
 setwgpeeraip(const char *aip, int param)
 {
 	int res;
@@ -5839,6 +5853,15 @@ unsetwgpeer(const char *peerkey_b64, int param)
 }
 
 void
+unsetwgpeerdesc(const char *descr, int param)
+{
+	if (wg_peer == NULL)
+		errx(1, "wgdescr: wgpeer not set");
+	wg_peer->p_flags |= WG_PEER_SET_DESCRIPTION;
+	strlcpy(wg_peer->p_description, "", IFDESCRSIZE);
+}
+
+void
 unsetwgpeerpsk(const char *value, int param)
 {
 	if (wg_peer == NULL)
@@ -5908,6 +5931,10 @@ wg_status(int ifaliases)
 			    key, sizeof(key));
 			printf("\twgpeer %s\n", key);
 
+			if (strlen(wg_peer->p_description))
+				printf("\t\twgdescr: %s\n",
+				    wg_peer->p_description);
+
 			if (wg_peer->p_flags & WG_PEER_HAS_PSK)
 				printf("\t\twgpsk (present)\n");