[oe-commits] Chen Qi : openssh: avoid checking empty passwords to mess up with PAM modules

[git at git.openembedded.org]

Module: openembedded-core.git
Branch: master-next
Commit: dc3913aa8247402dd0fcb7bc6fff0747e92b409d
URL:    http://git.openembedded.org/?p=openembedded-core.git&a=commit;h=dc3913aa8247402dd0fcb7bc6fff0747e92b409d

Author: Chen Qi <Qi.Chen at windriver.com>
Date:   Wed Jul  2 14:24:39 2014 +0800

openssh: avoid checking empty passwords to mess up with PAM modules

Previously, even if PAM is enabled for ssh, the daemon still tries to
authenticate an empty password. This leads to authentication failure
which would mess up with PAM modules.

As a result, if 'UsePAM', 'PermitEmptyPasswords' and 'PasswordAuthentication'
are enabled, no user can login correctly. We would meet the following error
message at the client side.

	Write failed: Broken Pipe

This patch fixes the above problem by checking whether PAM is enabled before
authenticating an empty password. After all, if PAM is enabled, the task of
authenticating passwords should be handled to PAM modules.

[YOCTO #6466]

Signed-off-by: Chen Qi <Qi.Chen at windriver.com>
Signed-off-by: Richard Purdie <richard.purdie at linuxfoundation.org>

---

 ...c-avoid-authenticate-empty-passwords-to-m.patch | 30 ++++++++++++++++++++++
 meta/recipes-connectivity/openssh/openssh_6.6p1.bb |  3 ++-
 2 files changed, 32 insertions(+), 1 deletion(-)

diff --git a/meta/recipes-connectivity/openssh/openssh/auth2-none.c-avoid-authenticate-empty-passwords-to-m.patch b/meta/recipes-connectivity/openssh/openssh/auth2-none.c-avoid-authenticate-empty-passwords-to-m.patch
new file mode 100644
index 0000000..ba13cd1
--- /dev/null
+++ b/meta/recipes-connectivity/openssh/openssh/auth2-none.c-avoid-authenticate-empty-passwords-to-m.patch
@@ -0,0 +1,30 @@
+Upstream-Status: Pending
+
+Subject: auth2-none.c: avoid authenticate empty passwords to mess up with PAM
+
+If UsePAM, PermitEmptyPasswords, PasswordAuthentication are enabled. The ssh daemon
+will try to authenticate an empty password, resulting in login failures of any user.
+If PAM is enabled, then we should leave the task of password authentication to PAM.
+
+Signed-off-by: Chen Qi <Qi.Chen at windriver.com>
+
+---
+ auth2-none.c |    2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/auth2-none.c b/auth2-none.c
+index c8c6c74..b48b2fd 100644
+--- a/auth2-none.c
++++ b/auth2-none.c
+@@ -61,7 +61,7 @@ userauth_none(Authctxt *authctxt)
+ {
+ 	none_enabled = 0;
+ 	packet_check_eom();
+-	if (options.permit_empty_passwd && options.password_authentication)
++	if (options.permit_empty_passwd && options.password_authentication && !options.use_pam)
+ 		return (PRIVSEP(auth_password(authctxt, "")));
+ 	return (0);
+ }
+-- 
+1.7.9.5
+
diff --git a/meta/recipes-connectivity/openssh/openssh_6.6p1.bb b/meta/recipes-connectivity/openssh/openssh_6.6p1.bb
index 8f32c2e..047a895 100644
--- a/meta/recipes-connectivity/openssh/openssh_6.6p1.bb
+++ b/meta/recipes-connectivity/openssh/openssh_6.6p1.bb
@@ -24,7 +24,8 @@ SRC_URI = "ftp://ftp.openbsd.org/pub/OpenBSD/OpenSSH/portable/openssh-${PV}.tar.
            file://add-test-support-for-busybox.patch \
            file://run-ptest \
            file://openssh-CVE-2014-2532.patch \
-           file://openssh-CVE-2014-2653.patch"
+           file://openssh-CVE-2014-2653.patch \
+           file://auth2-none.c-avoid-authenticate-empty-passwords-to-m.patch"
 
 PAM_SRC_URI = "file://sshd"