1 files changed, 112 insertions, 0 deletions
diff --git a/usr/src/lib/libcmdutils/common/uid.c b/usr/src/lib/libcmdutils/common/uid.c
new file mode 100644
index 0000000000..a5ca6c45bd
--- /dev/null
+++ b/usr/src/lib/libcmdutils/common/uid.c
@@ -0,0 +1,112 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License, Version 1.0 only
+ * (the "License").  You may not use this file except in compliance
+ * with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+/*
+ * Copyright (c) 1997-2001 by Sun Microsystems, Inc.
+ * All rights reserved.
+ */
+
+/*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
+/*	  All Rights Reserved  	*/
+
+/*
+ * Copyright (c) 2013 RackTop Systems.
+ */
+
+#include <errno.h>
+#include <sys/types.h>
+#include <stdio.h>
+#include <userdefs.h>
+#include <pwd.h>
+#include <libcmdutils.h>
+
+static int findunuseduid(uid_t start, uid_t stop, uid_t *ret);
+static boolean_t isreserveduid(uid_t uid);
+
+/*
+ * Find the highest unused uid. If the highest unused uid is "stop",
+ * then attempt to find a hole in the range. Returns 0 on success.
+ */
+int
+findnextuid(uid_t start, uid_t stop, uid_t *ret)
+{
+	uid_t uid = start;
+	struct passwd *pwd;
+	boolean_t overflow = B_FALSE;
+
+	setpwent();
+	for (pwd = getpwent(); pwd != NULL; pwd = getpwent()) {
+		if (isreserveduid(pwd->pw_uid))		/* Skip reserved IDs */
+			continue;
+		if (pwd->pw_uid >= uid) {
+			if (pwd->pw_uid == stop) {	/* Overflow check */
+				overflow = B_TRUE;
+				break;
+			}
+			uid = pwd->pw_uid + 1;
+		}
+	}
+	if (pwd == NULL && errno != 0) {
+		endpwent();
+		return (-1);
+	}
+	endpwent();
+	if (overflow == B_TRUE)				/* Find a hole */
+		return (findunuseduid(start, stop, ret));
+	while (isreserveduid(uid) && uid < stop)	/* Skip reserved IDs */
+		uid++;
+	*ret = uid;
+	return (0);
+}
+
+/*
+ * Check to see whether the uid is a reserved uid
+ * -- nobody, noaccess or nobody4
+ */
+static boolean_t
+isreserveduid(uid_t uid)
+{
+	return (uid == 60001 || uid == 60002 || uid == 65534);
+}
+
+/*
+ * findunuseduid() attempts to return the next valid usable id between the
+ * supplied upper and lower limits. Returns 0 on success.
+ */
+static int
+findunuseduid(uid_t start, uid_t stop, uid_t *ret)
+{
+	uid_t uid;
+
+	for (uid = start; uid <= stop; uid++) {
+		if (isreserveduid(uid))
+			continue;
+		if (getpwuid(uid) == NULL) {
+			if (errno != 0)
+				return (-1);
+			break;
+		}
+	}
+	if (uid > stop)
+		return (-1);
+	*ret = uid;
+	return (0);
+}