path: root/0001-Use-libpassphrase-when-entering-passwords.patch

From d5074436f7d8f9666fe1e6aac6d732ea62d182c8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Mattias=20Andr=C3=A9e?= <maandree@member.fsf.org>
Date: Sat, 5 Dec 2015 21:09:45 +0100
Subject: [PATCH 1/2] Use libpassphrase when entering passwords.
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libpassphrase can be compiled so that it can display
the strength of the password, including telling the
user that she is using a common passphrase.

As a bonus, libpassphrase can be configured to do
something else then just be slient without echoes.

Signed-off-by: Mattias Andrée <maandree@member.fsf.org>
---
 ChangeLog          | 10 ++++++++
 README             |  1 +
 lib/Makefile.am    |  6 +++--
 lib/pwauth.c       |  6 +++--
 lib/xgetpass.c     | 67 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 lib/xgetpass.h     | 35 ++++++++++++++++++++++++++++
 libmisc/pam_pass.c | 40 +++++++++++++++++++++++++++++++-
 src/gpasswd.c      |  6 +++--
 src/newgrp.c       |  4 +++-
 src/passwd.c       |  8 ++++---
 src/sulogin.c      |  6 +++--
 11 files changed, 176 insertions(+), 13 deletions(-)
 create mode 100644 lib/xgetpass.c
 create mode 100644 lib/xgetpass.h

diff --git a/ChangeLog b/ChangeLog
index 23cd5ae..bc43385 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+2015-12-05  Mattias Andrée  <maandree@member.fsf.org>
+
+	* lib/xgetpass.c: Add ability to use libpassphrase>=1449331105 instead of getpass.
+	* libmisc/pam_pass.c: Use xgetpass instead of misc_conv when entering (not retyping) the new password.
+	* lib/pwauth.c: Replace getpass with xgetpass.
+	* src/gpasswd.c: Likewise.
+	* src/newgrp.c: Likewise.
+	* src/passwd.c: Likewise.
+	* src/sulogin.c: Likewise.
+
 2014-05-09  Christian Perrier  <bubulle@debian.org>
 
 	* Include patches only included in Debian for 4.2
diff --git a/README b/README
index e531de6..5c27142 100644
--- a/README
+++ b/README
@@ -87,6 +87,7 @@ Leonard N. Zubkoff <lnz@dandelion.com>
 Luca Berra <bluca@www.polimi.it>
 Lukáš Kuklínek <lkukline@redhat.com>
 Lutz Schwalowsky <schwalow@mineralogie.uni-hamburg.de>
+Mattias Andrée <maandree@member.fsf.org>
 Marc Ewing <marc@redhat.com>
 Martin Bene <mb@sime.com>
 Martin Mares <mj@gts.cz>
diff --git a/lib/Makefile.am b/lib/Makefile.am
index 6db86cd..3fa3817 100644
--- a/lib/Makefile.am
+++ b/lib/Makefile.am
@@ -5,7 +5,7 @@ DEFS =
 
 noinst_LTLIBRARIES = libshadow.la
 
-libshadow_la_LDFLAGS = -version-info 0:0:0
+libshadow_la_LDFLAGS = -version-info 0:0:0 -lpassphrase
 
 libshadow_la_SOURCES = \
 	commonio.c \
@@ -53,7 +53,9 @@ libshadow_la_SOURCES = \
 	shadowio.h \
 	shadowmem.c \
 	spawn.c \
-	utent.c
+	utent.c \
+	xgetpass.c \
+	xgetpass.h
 
 if WITH_TCB
 libshadow_la_SOURCES += tcbfuncs.c tcbfuncs.h
diff --git a/lib/pwauth.c b/lib/pwauth.c
index 9e24fbf..6775465 100644
--- a/lib/pwauth.c
+++ b/lib/pwauth.c
@@ -3,6 +3,7 @@
  * Copyright (c) 1996 - 2000, Marek Michałkiewicz
  * Copyright (c) 2003 - 2006, Tomasz Kłoczko
  * Copyright (c) 2008 - 2009, Nicolas François
+ * Copyright (c) 2015       , Mattias Andrée
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -45,6 +46,7 @@
 #include "defines.h"
 #include "pwauth.h"
 #include "getdef.h"
+#include "xgetpass.h"
 #ifdef SKEY
 #include <skey.h>
 #endif
@@ -161,7 +163,7 @@ int pw_auth (const char *cipher,
 #endif
 
 		snprintf (prompt, sizeof prompt, cp, user);
-		clear = getpass (prompt);
+		clear = xgetpass (prompt, 0);
 		if (NULL == clear) {
 			static char c[1];
 
@@ -194,7 +196,7 @@ int pw_auth (const char *cipher,
 	 * -- AR 8/22/1999
 	 */
 	if ((0 != retval) && ('\0' == input[0]) && use_skey) {
-		clear = getpass (prompt);
+		clear = xgetpass (prompt, 0);
 		if (NULL == clear) {
 			static char c[1];
 
diff --git a/lib/xgetpass.c b/lib/xgetpass.c
new file mode 100644
index 0000000..a44ffc0
--- /dev/null
+++ b/lib/xgetpass.c
@@ -0,0 +1,67 @@
+/*
+ * Copyright (c) 2015       , Mattias Andrée
+ * 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. The name of the copyright holders or contributors may not be used to
+ *    endorse or promote products derived from this software without
+ *    specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 THE COPYRIGHT
+ * HOLDERS 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 <config.h>
+
+#ident "$Id$"
+
+#include <unistd.h>
+#include <passphrase.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <stdio.h>
+
+char *xgetpass (const char *prompt, int is_new)
+{
+	int fd, saved_errno;
+	char *pass;
+
+	fd = open ("/dev/tty", O_RDWR);
+	if (-1 == fd) {
+		return NULL;
+	}
+
+	passphrase_disable_echo1 (fd);
+	fprintf (stderr, "%s", prompt);
+	fflush (stderr);
+	pass = passphrase_read2 (fd, is_new
+	                         ? PASSPHRASE_READ_NEW |
+	                           PASSPHRASE_READ_SCREEN_FREE
+	                         : PASSPHRASE_READ_EXISTING);
+	saved_errno = errno;
+	passphrase_reenable_echo1 (fd);
+	errno = saved_errno;
+	return pass;
+
+	/*
+	return getpass (prompt);
+	(void) is_new;
+	*/
+}
+
diff --git a/lib/xgetpass.h b/lib/xgetpass.h
new file mode 100644
index 0000000..b1abbb0
--- /dev/null
+++ b/lib/xgetpass.h
@@ -0,0 +1,35 @@
+/*
+ * Copyright (c) 2015       , Mattias Andrée
+ * 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. The name of the copyright holders or contributors may not be used to
+ *    endorse or promote products derived from this software without
+ *    specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 THE COPYRIGHT
+ * HOLDERS 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.
+ */
+
+/*
+ *	$Id$
+ */
+
+
+char *xgetpass (const char *prompt, int is_new);
diff --git a/libmisc/pam_pass.c b/libmisc/pam_pass.c
index a89bb2c..93029ec 100644
--- a/libmisc/pam_pass.c
+++ b/libmisc/pam_pass.c
@@ -2,6 +2,7 @@
  * Copyright (c) 1997 - 1999, Marek Michałkiewicz
  * Copyright (c) 2001 - 2005, Tomasz Kłoczko
  * Copyright (c) 2008       , Nicolas François
+ * Copyright (c) 2015       , Mattias Andrée
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -42,22 +43,59 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
+#include <string.h>
 #include <sys/types.h>
 #include "defines.h"
 #include "pam_defs.h"
 #include "prototypes.h"
+#include "xgetpass.h"
+
+static int xgetpass_conv (int num_msg, const struct pam_message **msg,
+			  struct pam_response **resp, void *appdata_ptr)
+{
+	struct pam_response *response;
+	static int first_enter = 0;
+	int current;
+	int saved_errno;
+
+	if ((num_msg != 1) || (msg[0]->msg_style != PAM_PROMPT_ECHO_OFF))
+		return conv.conv (num_msg, msg, resp, appdata_ptr);
+
+	response = calloc((size_t)1, sizeof(struct pam_response));
+	if (response == NULL) {
+		return PAM_CONV_ERR;
+	}
+
+	current = strchr(msg[0]->msg, '(') != NULL;
+	first_enter ^= !current;
+	response->resp_retcode = 0;
+	response->resp = xgetpass (msg[0]->msg, first_enter & !current);
+	if (response->resp == NULL) {
+		saved_errno = errno;
+		free(response);
+		errno = saved_errno;
+		return PAM_CONV_ERR;
+	}
+
+	*resp = response;
+	return PAM_SUCCESS;
+}
+
 
 void do_pam_passwd (const char *user, bool silent, bool change_expired)
 {
 	pam_handle_t *pamh = NULL;
 	int flags = 0, ret;
+	struct pam_conv conv_proper = conv;
+
+	conv_proper.conv = xgetpass_conv;
 
 	if (silent)
 		flags |= PAM_SILENT;
 	if (change_expired)
 		flags |= PAM_CHANGE_EXPIRED_AUTHTOK;
 
-	ret = pam_start ("passwd", user, &conv, &pamh);
+	ret = pam_start ("passwd", user, &conv_proper, &pamh);
 	if (ret != PAM_SUCCESS) {
 		fprintf (stderr,
 			 _("passwd: pam_start() failed, error %d\n"), ret);
diff --git a/src/gpasswd.c b/src/gpasswd.c
index 8959a35..811a93d 100644
--- a/src/gpasswd.c
+++ b/src/gpasswd.c
@@ -3,6 +3,7 @@
  * Copyright (c) 1996 - 2000, Marek Michałkiewicz
  * Copyright (c) 2001 - 2006, Tomasz Kłoczko
  * Copyright (c) 2007 - 2011, Nicolas François
+ * Copyright (c) 2015       , Mattias Andrée
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -46,6 +47,7 @@
 #include "groupio.h"
 #include "nscd.h"
 #include "prototypes.h"
+#include "xgetpass.h"
 #ifdef SHADOWGRP
 #include "sgroupio.h"
 #endif
@@ -909,14 +911,14 @@ static void change_passwd (struct group *gr)
 	printf (_("Changing the password for group %s\n"), group);
 
 	for (retries = 0; retries < RETRIES; retries++) {
-		cp = getpass (_("New Password: "));
+		cp = xgetpass (_("New Password: "), 1);
 		if (NULL == cp) {
 			exit (1);
 		}
 
 		STRFCPY (pass, cp);
 		strzero (cp);
-		cp = getpass (_("Re-enter new password: "));
+		cp = xgetpass (_("Re-enter new password: "), 0);
 		if (NULL == cp) {
 			exit (1);
 		}
diff --git a/src/newgrp.c b/src/newgrp.c
index 49dd151..6ea3617 100644
--- a/src/newgrp.c
+++ b/src/newgrp.c
@@ -3,6 +3,7 @@
  * Copyright (c) 1996 - 2000, Marek Michałkiewicz
  * Copyright (c) 2001 - 2006, Tomasz Kłoczko
  * Copyright (c) 2007 - 2008, Nicolas François
+ * Copyright (c) 2015       , Mattias Andrée
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -42,6 +43,7 @@
 #include "defines.h"
 #include "getdef.h"
 #include "prototypes.h"
+#include "xgetpass.h"
 /*@-exitarg@*/
 #include "exitcodes.h"
 
@@ -171,7 +173,7 @@ static void check_perms (const struct group *grp,
 		 * get the password from her, and set the salt for
 		 * the decryption from the group file.
 		 */
-		cp = getpass (_("Password: "));
+		cp = xgetpass (_("Password: "), 0);
 		if (NULL == cp) {
 			goto failure;
 		}
diff --git a/src/passwd.c b/src/passwd.c
index 3424f3b..c2cac67 100644
--- a/src/passwd.c
+++ b/src/passwd.c
@@ -3,6 +3,7 @@
  * Copyright (c) 1996 - 2000, Marek Michałkiewicz
  * Copyright (c) 2001 - 2006, Tomasz Kłoczko
  * Copyright (c) 2007 - 2011, Nicolas François
+ * Copyright (c) 2015       , Mattias Andrée
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -55,6 +56,7 @@
 #include "pwauth.h"
 #include "pwio.h"
 #include "shadowio.h"
+#include "xgetpass.h"
 
 /*
  * exit status values
@@ -237,7 +239,7 @@ static int new_password (const struct passwd *pw)
 	 */
 
 	if (!amroot && ('\0' != crypt_passwd[0])) {
-		clear = getpass (_("Old password: "));
+		clear = xgetpass (_("Old password: "), 1);
 		if (NULL == clear) {
 			return -1;
 		}
@@ -312,7 +314,7 @@ static int new_password (const struct passwd *pw)
 
 	warned = false;
 	for (i = getdef_num ("PASS_CHANGE_TRIES", 5); i > 0; i--) {
-		cp = getpass (_("New password: "));
+		cp = xgetpass (_("New password: "), 1);
 		if (NULL == cp) {
 			memzero (orig, sizeof orig);
 			return -1;
@@ -339,7 +341,7 @@ static int new_password (const struct passwd *pw)
 			warned = true;
 			continue;
 		}
-		cp = getpass (_("Re-enter new password: "));
+		cp = xgetpass (_("Re-enter new password: "), 0);
 		if (NULL == cp) {
 			memzero (orig, sizeof orig);
 			return -1;
diff --git a/src/sulogin.c b/src/sulogin.c
index ccbf2c5..1296856 100644
--- a/src/sulogin.c
+++ b/src/sulogin.c
@@ -3,6 +3,7 @@
  * Copyright (c) 1996 - 2000, Marek Michałkiewicz
  * Copyright (c) 2002 - 2006, Tomasz Kłoczko
  * Copyright (c) 2007 - 2010, Nicolas François
+ * Copyright (c) 2015       , Mattias Andrée
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -43,6 +44,7 @@
 #include "getdef.h"
 #include "prototypes.h"
 #include "pwauth.h"
+#include "xgetpass.h"
 /*@-exitarg@*/
 #include "exitcodes.h"
 
@@ -202,10 +204,10 @@ static RETSIGTYPE catch_signals (unused int sig)
 		 */
 
 		/* get a password for root */
-		cp = getpass (_(
+		cp = xgetpass (_(
 "\n"
 "Type control-d to proceed with normal startup,\n"
-"(or give root password for system maintenance):"));
+"(or give root password for system maintenance): "), 0);
 		/*
 		 * XXX - can't enter single user mode if root password is
 		 * empty.  I think this doesn't happen very often :-). But
-- 
2.6.3