[svn-upgrade] Integrating new upstream version, shadow (19990709)

libmisc/chkname.c

@@ -0,0 +1,73 @@
+/*
+ * check_user_name(), check_group_name() - check the new user/group
+ * name for validity; return value: 1 - OK, 0 - bad name
+ */
+
+#include <config.h>
+
+#include "rcsid.h"
+RCSID("$Id: chkname.c,v 1.4 1998/04/16 19:57:43 marekm Exp $")
+
+#include <ctype.h>
+#include "defines.h"
+#include "chkname.h"
+
+#if HAVE_UTMPX_H
+#include <utmpx.h>
+#else
+#include <utmp.h>
+#endif
+
+static int
+good_name(const char *name)
+{
+	/*
+	 * User/group names must start with a letter, and may not
+	 * contain colons, commas, newlines (used in passwd/group
+	 * files...) or any non-printable characters.
+	 */
+	if (!*name || !isalpha(*name))
+		return 0;
+
+	while (*name) {
+		if (*name == ':' || *name == ',' ||
+		    *name == '\n' || !isprint(*name))
+			return 0;
+
+		name++;
+	}
+
+	return 1;
+}
+
+int
+check_user_name(const char *name)
+{
+#if HAVE_UTMPX_H
+	struct utmpx ut;
+#else
+	struct utmp ut;
+#endif
+
+	/*
+	 * User names are limited by whatever utmp can
+	 * handle (usually max 8 characters).
+	 */
+	if (strlen(name) > sizeof(ut.ut_user))
+		return 0;
+
+	return good_name(name);
+}
+
+int
+check_group_name(const char *name)
+{
+	/*
+	 * Arbitrary limit for group names - max 16
+	 * characters (same as on HP-UX 10).
+	 */
+	if (strlen(name) > 16)
+		return 0;
+
+	return good_name(name);
+}