use mktemp, but use it without guessability or DOS attacks

2 files changed, 25 insertions, 18 deletions

diff --git a/usr.sbin/pkg_install/delete/perform.c b/usr.sbin/pkg_install/delete/perform.c
index 06edcaad3d7..0478d86b566 100644
--- a/usr.sbin/pkg_install/delete/perform.c
+++ b/usr.sbin/pkg_install/delete/perform.c
@@ -1,7 +1,7 @@
-/*	$OpenBSD: perform.c,v 1.2 1996/06/04 08:43:38 niklas Exp $	*/
+/*	$OpenBSD: perform.c,v 1.3 1997/06/17 08:38:03 deraadt Exp $	*/
 
 #ifndef lint
-static const char *rcsid = "$OpenBSD: perform.c,v 1.2 1996/06/04 08:43:38 niklas Exp $";
+static const char *rcsid = "$OpenBSD: perform.c,v 1.3 1997/06/17 08:38:03 deraadt Exp $";
 #endif
 
 /*
@@ -177,7 +177,7 @@ undepend(PackingList p, char *pkgname)
 	 whinge("Couldn't open dependency file `%s'", fname);
 	 return;
      }
-     sprintf(ftmp, "%s.XXXXXX", fname);
+     sprintf(ftmp, "%s.XXXXXXXXXX", fname);
      s = mkstemp(ftmp);
      if (s == -1) {
 	 fclose(fp);
diff --git a/usr.sbin/pkg_install/lib/pen.c b/usr.sbin/pkg_install/lib/pen.c
index 42c89b6e715..ca1d501595c 100644
--- a/usr.sbin/pkg_install/lib/pen.c
+++ b/usr.sbin/pkg_install/lib/pen.c
@@ -1,7 +1,7 @@
-/*	$OpenBSD: pen.c,v 1.2 1996/06/04 08:43:45 niklas Exp $	*/
+/*	$OpenBSD: pen.c,v 1.3 1997/06/17 08:38:03 deraadt Exp $	*/
 
 #ifndef lint
-static const char *rcsid = "$OpenBSD: pen.c,v 1.2 1996/06/04 08:43:45 niklas Exp $";
+static const char *rcsid = "$OpenBSD: pen.c,v 1.3 1997/06/17 08:38:03 deraadt Exp $";
 #endif
 
 /*
@@ -49,15 +49,15 @@ find_play_pen(char *pen, size_t sz)
     if (pen[0] && stat(pen, &sb) != FAIL && (min_free(pen) >= sz))
 	return pen;
     else if ((cp = getenv("PKG_TMPDIR")) != NULL && stat(cp, &sb) != FAIL && (min_free(cp) >= sz))
-	sprintf(pen, "%s/instmp.XXXXXX", cp);
+	sprintf(pen, "%s/instmp.XXXXXXXXXX", cp);
     else if ((cp = getenv("TMPDIR")) != NULL && stat(cp, &sb) != FAIL && (min_free(cp) >= sz))
-	sprintf(pen, "%s/instmp.XXXXXX", cp);
+	sprintf(pen, "%s/instmp.XXXXXXXXXX", cp);
     else if (stat("/var/tmp", &sb) != FAIL && min_free("/var/tmp") >= sz)
-	strcpy(pen, "/var/tmp/instmp.XXXXXX");
+	strcpy(pen, "/var/tmp/instmp.XXXXXXXXXX");
     else if (stat("/tmp", &sb) != FAIL && min_free("/tmp") >= sz)
-	strcpy(pen, "/tmp/instmp.XXXXXX");
+	strcpy(pen, "/tmp/instmp.XXXXXXXXXX");
     else if ((stat("/usr/tmp", &sb) == SUCCESS || mkdir("/usr/tmp", 01777) == SUCCESS) && min_free("/usr/tmp") >= sz)
-	strcpy(pen, "/usr/tmp/instmp.XXXXXX");
+	strcpy(pen, "/usr/tmp/instmp.XXXXXXXXXX");
     else {
 	barf("Can't find enough temporary space to extract the files, please set\n"
 	     "your PKG_TMPDIR environment variable to a location with at least %d bytes\n"
@@ -75,18 +75,25 @@ char *
 make_playpen(char *pen, size_t sz)
 {
     char *tmp;
+    int i = 0;
 
-    if (!find_play_pen(pen, sz))
-	return NULL;
+    while (1) {
+	if (!find_play_pen(pen, sz))
+	    return NULL;
 
-    if (!mktemp(pen)) {
-	barf("Can't mktemp '%s'.", pen);
-	return NULL;
-    }
-    if (mkdir(pen, 0755) == FAIL) {
-	barf("Can't mkdir '%s'.", pen);
+        if (!mktemp(pen)) {
+	    barf("Can't mktemp '%s'.", pen);
+	    return NULL;
+        }
+        if (mkdir(pen, 0755) == FAIL && i++ < 100) {
+	    /* try again! */
+	    continue;
+	}
+
+        barf("Can't mkdir '%s'.", pen);
 	return NULL;
     }
+
     if (Verbose) {
 	if (sz)
 	    fprintf(stderr, "Requested space: %d bytes, free space: %d bytes in %s\n", (int)sz, min_free(pen), pen);