in server mode, create /tmp/aucat-userid/ directory with

permissions 0700, and create sockets in it. This prevents
one local user to eavesdrop or disturb audio programs of
other users.

if you're using the ``-s socket'' option with an absolute
path as argument, please update it to use a socket name.

requested by many, bits from jakemsr and otto
ok jakemsr

4 files changed, 45 insertions, 22 deletions

diff --git a/usr.bin/aucat/aucat.1 b/usr.bin/aucat/aucat.1
index 490d8640f6f..20ce5a2f8bf 100644
--- a/usr.bin/aucat/aucat.1
+++ b/usr.bin/aucat/aucat.1
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: aucat.1,v 1.44 2009/01/23 17:52:13 ratchov Exp $
+.\"	$OpenBSD: aucat.1,v 1.45 2009/02/03 19:44:58 ratchov Exp $
 .\"
 .\" Copyright (c) 2006 Alexandre Ratchov <alex@caoua.org>
 .\"
@@ -14,7 +14,7 @@
 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
-.Dd $Mdocdate: January 23 2009 $
+.Dd $Mdocdate: February 3 2009 $
 .Dt AUCAT 1
 .Os
 .Sh NAME
@@ -87,9 +87,9 @@ instead of the regular
 .Xr audio 4
 device for audio input and output
 in order to share the physical device with other clients.
-The default socket path is
-.Pa /tmp/aucat.sock
-but other paths can be used with the
+The default socket name is
+.Pa default
+but other names can be used with the
 .Fl s
 option.
 .It Fl m Ar mode
@@ -117,9 +117,11 @@ then standard output will be used.
 Sample rate in Hertz of the playback or record stream.
 The default is 44100Hz.
 .It Fl s Ar socket
-Add the path
+Add the name
 .Ar socket
 to the list of sockets to listen on.
+.Ar socket
+cannot contain '/'.
 Meaningful in server mode only.
 .It Fl u
 Normally
@@ -363,7 +365,7 @@ in server mode using default parameters, but will create an
 additional socket for output to channels 2:3 only (rear speakers
 on most cards):
 .Bd -literal -offset indent
-$ aucat -l -s /tmp/aucat.sock -c 2:3 -s /tmp/aucat.sock.rear
+$ aucat -l -s default -c 2:3 -s rear
 .Ed
 .Pp
 The following will start
@@ -371,7 +373,7 @@ The following will start
 in server mode creating the default socket with low volume and
 an additional socket for high volume output:
 .Bd -literal -offset indent
-$ aucat -l -v 65 -s /tmp/aucat.sock -v 127 -s /tmp/aucat.sock.max
+$ aucat -l -v 65 -s default -v 127 -s max
 .Ed
 .Sh SEE ALSO
 .Xr audioctl 1 ,
diff --git a/usr.bin/aucat/aucat.c b/usr.bin/aucat/aucat.c
index ad2b9fb15c4..ba86b9d9a9c 100644
--- a/usr.bin/aucat/aucat.c
+++ b/usr.bin/aucat/aucat.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: aucat.c,v 1.54 2009/01/25 17:07:39 ratchov Exp $	*/
+/*	$OpenBSD: aucat.c,v 1.55 2009/02/03 19:44:58 ratchov Exp $	*/
 /*
  * Copyright (c) 2008 Alexandre Ratchov <alex@caoua.org>
  *
@@ -47,10 +47,12 @@
 #include <sys/param.h>
 #include <sys/types.h>
 #include <sys/queue.h>
+#include <sys/stat.h>
 
-#include <signal.h>
 #include <err.h>
+#include <errno.h>
 #include <fcntl.h>
+#include <limits.h>
 #include <signal.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -317,10 +319,13 @@ main(int argc, char **argv)
 	struct farglist  ifiles, ofiles, sfiles;
 	struct aparams ipar, opar, dipar, dopar;
 	struct sigaction sa;
+	struct stat sb;
+	char base[PATH_MAX], path[PATH_MAX];
 	unsigned bufsz, mode;
 	char *devpath, *dbgenv;
 	const char *errstr;
 	unsigned volctl;
+	uid_t uid;
 
 	dbgenv = getenv("AUCAT_DEBUG");
 	if (dbgenv) {
@@ -482,6 +487,18 @@ main(int argc, char **argv)
 		}
 	}
 
+	if (l_flag) {
+		uid = geteuid();
+		snprintf(base, PATH_MAX, "/tmp/aucat-%u", uid);
+		if (mkdir(base, 0700) < 0) {
+			if (errno != EEXIST)
+				err(1, "mkdir(\"%s\")", base);
+		}
+		if (stat(base, &sb) < 0)
+			err(1, "stat(\"%s\")", base);
+		if (sb.st_uid != uid || (sb.st_mode & 077) != 0)
+			errx(1, "%s has wrong permissions", base);
+	}
 	quit_flag = 0;
 	sigfillset(&sa.sa_mask);
 	sa.sa_flags = SA_RESTART;
@@ -533,8 +550,11 @@ main(int argc, char **argv)
 	while (!SLIST_EMPTY(&sfiles)) {
 		fa = SLIST_FIRST(&sfiles);
 		SLIST_REMOVE_HEAD(&sfiles, entry);
-		(void)listen_new(&listen_ops, fa->name,
-		    &fa->opar, &fa->ipar, MIDI_TO_ADATA(fa->vol));
+		if (strchr(fa->name, '/') != NULL)
+			errx(1, "socket names must not contain '/'");
+		snprintf(path, PATH_MAX, "%s/%s", base, fa->name);
+		listen_new(&listen_ops, path, &fa->opar, &fa->ipar,
+		    MIDI_TO_ADATA(fa->vol));
 		free(fa);
 	}
 
@@ -572,8 +592,11 @@ main(int argc, char **argv)
 			}
 		}
 	}
-	if (l_flag)
+	if (l_flag) {
 		filelist_unlisten();
+		if (rmdir(base) < 0)
+			warn("rmdir(\"%s\")", base);
+	}
 	if (suspend) {
 		DPRINTF("resuming to drain\n");
 		suspend = 0;
diff --git a/usr.bin/aucat/conf.h b/usr.bin/aucat/conf.h
index 3627eebe090..9d2105dd5ce 100644
--- a/usr.bin/aucat/conf.h
+++ b/usr.bin/aucat/conf.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: conf.h,v 1.5 2008/11/10 23:25:37 ratchov Exp $	*/
+/*	$OpenBSD: conf.h,v 1.6 2009/02/03 19:44:58 ratchov Exp $	*/
 /*
  * Copyright (c) 2008 Alexandre Ratchov <alex@caoua.org>
  *
@@ -56,7 +56,7 @@ extern int debug_level;
  */
 #define WAV_NBLK 6
 
-#define DEFAULT_DEVICE	"/dev/audio"	/* defaul device */
-#define DEFAULT_SOCKET	"/tmp/aucat.sock"
+#define DEFAULT_DEVICE	"/dev/audio"
+#define DEFAULT_SOCKET	"default"
 
 #endif /* !defined(CONF_H) */
diff --git a/usr.bin/aucat/listen.c b/usr.bin/aucat/listen.c
index da17643451a..fc6a3cacaab 100644
--- a/usr.bin/aucat/listen.c
+++ b/usr.bin/aucat/listen.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: listen.c,v 1.6 2009/01/23 17:38:15 ratchov Exp $	*/
+/*	$OpenBSD: listen.c,v 1.7 2009/02/03 19:44:58 ratchov Exp $	*/
 /*
  * Copyright (c) 2008 Alexandre Ratchov <alex@caoua.org>
  *
@@ -49,7 +49,7 @@ struct listen *
 listen_new(struct fileops *ops, char *path,
     struct aparams *wpar, struct aparams *rpar, int maxweight)
 {
-	int sock;
+	int sock, oldumask;
 	struct sockaddr_un sockname;
 	struct listen *f;
 
@@ -64,15 +64,13 @@ listen_new(struct fileops *ops, char *path,
 	}
 	sockname.sun_family = AF_UNIX;
 	strlcpy(sockname.sun_path, path, sizeof(sockname.sun_path));
+	oldumask = umask(0111);
 	if (bind(sock, (struct sockaddr *)&sockname,
 		sizeof(struct sockaddr_un)) < 0) {
 		perror("bind");
 		exit(1);
 	}
-	if (chmod(sockname.sun_path, 0777) < 0) {
-		/* not fatal, just print error */
-		perror(sockname.sun_path);
-	}
+	umask(oldumask);
 	if (listen(sock, 1) < 0) {
 		perror("listen");
 		exit(1);