Port over the last of the tinylogin applets

-Erik

libbb/correct_password.c

@@ -0,0 +1,78 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Copyright 1989 - 1991, Julianne Frances Haugh <jockgrrl@austin.rr.com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of Julianne F. Haugh nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY JULIE HAUGH AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL JULIE HAUGH OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <stdio.h>
+#include <errno.h>
+#include <unistd.h>
+#include <string.h>
+#include <stdlib.h>
+#include <syslog.h>
+#include <ctype.h>
+#include <crypt.h>
+
+#include "libbb.h"
+
+
+
+/* Ask the user for a password.
+   Return 1 if the user gives the correct password for entry PW,
+   0 if not.  Return 1 without asking for a password if run by UID 0
+   or if PW has an empty password.  */
+
+int correct_password ( const struct passwd *pw )
+{
+	char *unencrypted, *encrypted, *correct;
+	
+#ifdef CONFIG_FEATURE_SHADOWPASSWDS
+	if (( strcmp ( pw-> pw_passwd, "x" ) == 0 ) || ( strcmp ( pw-> pw_passwd, "*" ) == 0 )) {
+		struct spwd *sp = getspnam ( pw-> pw_name );
+		
+		if ( !sp )
+			error_msg_and_die ( "no valid shadow password" );
+		
+		correct = sp-> sp_pwdp;
+	}
+	else
+#endif
+    	correct = pw-> pw_passwd;
+
+	if ( correct == 0 || correct[0] == '\0' )
+		return 1;
+
+	unencrypted = getpass ( "Password: " );
+	if ( !unencrypted )
+	{
+		fputs ( "getpass: cannot open /dev/tty\n", stderr );
+		return 0;
+	}
+	encrypted = crypt ( unencrypted, correct );
+	memset ( unencrypted, 0, xstrlen ( unencrypted ));
+	return ( strcmp ( encrypted, correct ) == 0 ) ? 1 : 0;
+}