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

The following changes since commit c36d459f0d40bdbd3ba809835e0475e8992bc778:

python3: fix builtins imports (2014-06-30 16:35:03 +0100)

are available in the git repository at:

git://git.openembedded.org/openembedded-core-contrib ChenQi/openssh-pam
http://cgit.openembedded.org/cgit.cgi/openembedded-core-contrib/log/?h=ChenQi/openssh-pam

Chen Qi (1):
openssh: avoid checking empty passwords to mess up with PAM modules

 ...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(-)
 create mode 100644 meta/recipes-connectivity/openssh/openssh/auth2-none.c-avoid-authenticate-empty-passwords-to-m.patch

1.7.9.5

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]

---
 ...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(-)
 create mode 100644 meta/recipes-connectivity/openssh/openssh/auth2-none.c-avoid-authenticate-empty-passwords-to-m.patch

new file mode 100644
index 0000000..ba13cd1
@@ -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 <[email protected]>
+
+---
+ 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
+

index 8f32c2e..047a895 100644
@@ -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"
 

1.7.9.5