Introduce 'auto-join' to the wifi 802.11 stack.

This allows a system to remember which ESSIDs it wants to connect to, any
relevant security configuration, and switch to it when the network we are
currently connected to is no longer available.

Works when connecting and switching between WPA2/WPA1/WEP/clear encryptions.

example hostname.if:
join home wpakey password
join work wpakey mekmitasdigoat
join open-lounge
join cafe wpakey cafe2018
join "wepnetwork" nwkey "12345"
dhcp
inet6 autoconf
up

OK stsp@ reyk@
and enthusiasm from every hackroom I've been in for the last 3 years

2 files changed, 118 insertions, 9 deletions

diff --git a/sbin/ifconfig/ifconfig.8 b/sbin/ifconfig/ifconfig.8
index 95622f0be9a..951b046716f 100644
--- a/sbin/ifconfig/ifconfig.8
+++ b/sbin/ifconfig/ifconfig.8
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: ifconfig.8,v 1.308 2018/05/05 16:52:59 jmc Exp $
+.\"	$OpenBSD: ifconfig.8,v 1.309 2018/07/11 20:18:09 phessler 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 5 2018 $
+.Dd $Mdocdate: July 11 2018 $
 .Dt IFCONFIG 8
 .Os
 .Sh NAME
@@ -897,6 +897,7 @@ will begin advertising as master.
 .Op Oo Fl Oc Ns Cm chan Op Ar n
 .Op Oo Fl Oc Ns Cm nwflag Ar flag
 .Op Oo Fl Oc Ns Cm nwid Ar id
+.Op Oo Fl Oc Ns Cm join Op Ar id
 .Op Oo Fl Oc Ns Cm nwkey Ar key
 .Op Oo Fl Oc Ns Cm powersave Op Ar duration
 .Op Cm scan
@@ -969,6 +970,24 @@ Note that network ID is synonymous with Extended Service Set ID (ESSID).
 .It Cm -nwid
 Set the network ID to the empty string to allow the interface to connect
 to any available access point.
+.It Cm join Op Ar id
+Configure network ID.
+The
+.Ar id
+will be used to auto-join wireless networks.
+The
+.Ar id
+can either be any text string up to 32 characters in length,
+or a series of hexadecimal digits up to 64 digits.
+Any necessary
+.Cm wpakey
+or
+.Cm nwkey
+arguments should be specified on the same line.
+.Pp
+If no
+.Ar id
+is specified, show the list of currently configured auto-join networks.
 .It Cm nwkey Ar key
 Enable WEP encryption using the specified
 .Ar key .
diff --git a/sbin/ifconfig/ifconfig.c b/sbin/ifconfig/ifconfig.c
index b7413832a9a..af15dac4ae9 100644
--- a/sbin/ifconfig/ifconfig.c
+++ b/sbin/ifconfig/ifconfig.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ifconfig.c,v 1.367 2018/05/28 08:53:35 kn Exp $	*/
+/*	$OpenBSD: ifconfig.c,v 1.368 2018/07/11 20:18:09 phessler Exp $	*/
 /*	$NetBSD: ifconfig.c,v 1.40 1997/10/01 02:19:43 enami Exp $	*/
 
 /*
@@ -185,6 +185,8 @@ void	setifbroadaddr(const char *, int);
 void	setifmtu(const char *, int);
 void	setifllprio(const char *, int);
 void	setifnwid(const char *, int);
+void	setifjoin(const char *, int);
+void	delifjoin(const char *, int);
 void	setifbssid(const char *, int);
 void	setifnwkey(const char *, int);
 void	setifwpa(const char *, int);
@@ -373,6 +375,8 @@ const struct	cmd {
 	{ "mtu",	NEXTARG,	0,		setifmtu },
 	{ "nwid",	NEXTARG,	0,		setifnwid },
 	{ "-nwid",	-1,		0,		setifnwid },
+	{ "join",	NEXTARG0,	0,		setifjoin },
+	{ "-join",	NEXTARG0,	0,		delifjoin },
 	{ "bssid",	NEXTARG,	0,		setifbssid },
 	{ "-bssid",	-1,		0,		setifbssid },
 	{ "nwkey",	NEXTARG,	0,		setifnwkey },
@@ -659,6 +663,9 @@ const struct afswtch {
 
 const struct afswtch *afp;	/*the address family being set or asked about*/
 
+char joinname[IEEE80211_NWID_LEN];
+char nwidname[IEEE80211_NWID_LEN];
+
 int ifaliases = 0;
 int aflag = 0;
 
@@ -1636,12 +1643,75 @@ setifnwid(const char *val, int d)
 	}
 	nwid.i_len = len;
 	(void)strlcpy(ifr.ifr_name, name, sizeof(ifr.ifr_name));
+	(void)strlcpy(nwidname, nwid.i_nwid, sizeof(nwidname));
 	ifr.ifr_data = (caddr_t)&nwid;
 	if (ioctl(s, SIOCS80211NWID, (caddr_t)&ifr) < 0)
 		warn("SIOCS80211NWID");
 }
 
 void
+setifjoin(const char *val, int d)
+{
+	struct ieee80211_join join;
+	int len;
+
+	if (val == NULL) {
+		/* TODO: display the list of join'd networks */
+		return;
+	}
+
+	if (d != 0) {
+		/* no network id is especially desired */
+		memset(&join, 0, sizeof(join));
+		len = 0;
+	} else {
+		len = sizeof(join.i_nwid);
+		if (get_string(val, NULL, join.i_nwid, &len) == NULL)
+			return;
+	}
+	join.i_len = len;
+	(void)strlcpy(ifr.ifr_name, name, sizeof(ifr.ifr_name));
+	(void)strlcpy(joinname, join.i_nwid, sizeof(joinname));
+	ifr.ifr_data = (caddr_t)&join;
+	if (ioctl(s, SIOCS80211JOIN, (caddr_t)&ifr) < 0)
+		warn("SIOCS80211JOIN");
+}
+
+void
+delifjoin(const char *val, int d)
+{
+	struct ieee80211_join join;
+	int len;
+
+	memset(&join, 0, sizeof(join));
+	len = 0;
+	join.i_flags |= IEEE80211_JOIN_DEL;
+
+	if (val == NULL) {
+		ifr.ifr_data = (caddr_t)&join;
+		if (ioctl(s, SIOCS80211JOIN, (caddr_t)&ifr) < 0)
+			warn("SIOCS80211JOIN");
+		return;
+	}
+
+	if (d != 0) {
+		/* no network id is especially desired */
+		memset(&join, 0, sizeof(join));
+		len = 0;
+	} else {
+		len = sizeof(join.i_nwid);
+		if (val != NULL &&
+		    get_string(val, NULL, join.i_nwid, &len) == NULL)
+			return;
+	}
+	join.i_len = len;
+	(void)strlcpy(ifr.ifr_name, name, sizeof(ifr.ifr_name));
+	ifr.ifr_data = (caddr_t)&join;
+	if (ioctl(s, SIOCS80211JOIN, (caddr_t)&ifr) < 0)
+		warn("SIOCS80211JOIN");
+}
+
+void
 setifbssid(const char *val, int d)
 {
 
@@ -1923,8 +1993,20 @@ setifwpakey(const char *val, int d)
 		memset(&ifr, 0, sizeof(ifr));
 		ifr.ifr_data = (caddr_t)&nwid;
 		strlcpy(ifr.ifr_name, name, sizeof(ifr.ifr_name));
-		if (ioctl(s, SIOCG80211NWID, (caddr_t)&ifr))
-			err(1, "SIOCG80211NWID");
+
+		/* Use the value specified in 'join' or 'nwid' */
+		if (strlen(joinname) != 0) {
+			strlcpy(nwid.i_nwid, joinname, sizeof(nwid.i_nwid));
+			nwid.i_len = strlen(joinname);
+		} else if (strlen(nwidname) != 0) {
+			strlcpy(nwid.i_nwid, nwidname, sizeof(nwid.i_nwid));
+			nwid.i_len = strlen(nwidname);
+		} else {
+			warnx("no nwid or join command, guessing nwid to use");
+
+			if (ioctl(s, SIOCG80211NWID, (caddr_t)&ifr))
+				err(1, "SIOCG80211NWID");
+		}
 
 		passlen = strlen(val);
 		if (passlen == 2 + 2 * sizeof(psk.i_psk) &&
@@ -2082,9 +2164,10 @@ print_cipherset(u_int32_t cipherset)
 void
 ieee80211_status(void)
 {
-	int len, i, nwkey_verbose, inwid, inwkey, ipsk, ichan, ipwr;
+	int len, i, nwkey_verbose, inwid, ijoin, inwkey, ipsk, ichan, ipwr;
 	int ibssid, iwpa;
 	struct ieee80211_nwid nwid;
+	struct ieee80211_join join;
 	struct ieee80211_nwkey nwkey;
 	struct ieee80211_wpapsk psk;
 	struct ieee80211_power power;
@@ -2102,6 +2185,10 @@ ieee80211_status(void)
 	strlcpy(ifr.ifr_name, name, sizeof(ifr.ifr_name));
 	inwid = ioctl(s, SIOCG80211NWID, (caddr_t)&ifr);
 
+	ifr.ifr_data = (caddr_t)&join;
+	strlcpy(ifr.ifr_name, name, sizeof(ifr.ifr_name));
+	ijoin = ioctl(s, SIOCG80211JOIN, (caddr_t)&ifr);
+
 	memset(&nwkey, 0, sizeof(nwkey));
 	strlcpy(nwkey.i_name, name, sizeof(nwkey.i_name));
 	inwkey = ioctl(s, SIOCG80211NWKEY, (caddr_t)&nwkey);
@@ -2127,8 +2214,8 @@ ieee80211_status(void)
 	iwpa = ioctl(s, SIOCG80211WPAPARMS, &wpa);
 
 	/* check if any ieee80211 option is active */
-	if (inwid == 0 || inwkey == 0 || ipsk == 0 || ipwr == 0 ||
-	    ichan == 0 || ibssid == 0 || iwpa == 0)
+	if (inwid == 0 || ijoin == 0 || inwkey == 0 || ipsk == 0 ||
+	    ipwr == 0 || ichan == 0 || ibssid == 0 || iwpa == 0)
 		fputs("\tieee80211:", stdout);
 	else
 		return;
@@ -2138,7 +2225,10 @@ ieee80211_status(void)
 		len = nwid.i_len;
 		if (len > IEEE80211_NWID_LEN)
 			len = IEEE80211_NWID_LEN;
-		fputs(" nwid ", stdout);
+		if (ijoin == 0 && join.i_flags & IEEE80211_JOIN_FOUND)
+			fputs(" join ", stdout);
+		else
+			fputs(" nwid ", stdout);
 		print_string(nwid.i_nwid, len);
 	}