openssh/openssh-7.2p2-pam_check_locks.patch

# HG changeset patch
# Parent  ac7f843cd7ebec413691d51823cdc67b611abdff
new option UsePAMCheckLocks to enforce checking for locked accounts while
UsePAM is used

bnc#708678, FATE#312033

diff --git a/openssh-7.2p2/auth.c b/openssh-7.2p2/auth.c
--- a/openssh-7.2p2/auth.c
+++ b/openssh-7.2p2/auth.c
@@ -104,17 +104,17 @@ allowed_user(struct passwd * pw)
 	struct spwd *spw = NULL;
 #endif
 
 	/* Shouldn't be called if pw is NULL, but better safe than sorry... */
 	if (!pw || !pw->pw_name)
 		return 0;
 
 #ifdef USE_SHADOW
-	if (!options.use_pam)
+	if (!options.use_pam || options.use_pam_check_locks)
 		spw = getspnam(pw->pw_name);
 #ifdef HAS_SHADOW_EXPIRE
 	if (!options.use_pam && spw != NULL && auth_shadow_acctexpired(spw))
 		return 0;
 #endif /* HAS_SHADOW_EXPIRE */
 #endif /* USE_SHADOW */
 
 	/* grab passwd field for locked account check */
@@ -124,17 +124,17 @@ allowed_user(struct passwd * pw)
 #ifdef USE_LIBIAF
 		passwd = get_iaf_password(pw);
 #else
 		passwd = spw->sp_pwdp;
 #endif /* USE_LIBIAF */
 #endif
 
 	/* check for locked account */
-	if (!options.use_pam && passwd && *passwd) {
+	if ((!options.use_pam || options.use_pam_check_locks) && passwd && *passwd) {
 		int locked = 0;
 
 #ifdef LOCKED_PASSWD_STRING
 		if (strcmp(passwd, LOCKED_PASSWD_STRING) == 0)
 			 locked = 1;
 #endif
 #ifdef LOCKED_PASSWD_PREFIX
 		if (strncmp(passwd, LOCKED_PASSWD_PREFIX,
diff --git a/openssh-7.2p2/servconf.c b/openssh-7.2p2/servconf.c
--- a/openssh-7.2p2/servconf.c
+++ b/openssh-7.2p2/servconf.c
@@ -69,16 +69,17 @@ extern Buffer cfg;
 
 void
 initialize_server_options(ServerOptions *options)
 {
 	memset(options, 0, sizeof(*options));
 
 	/* Portable-specific options */
 	options->use_pam = -1;
+	options->use_pam_check_locks = -1;
 
 	/* Standard Options */
 	options->num_ports = 0;
 	options->ports_from_cmdline = 0;
 	options->queued_listen_addrs = NULL;
 	options->num_queued_listens = 0;
 	options->listen_addrs = NULL;
 	options->address_family = -1;
@@ -195,16 +196,18 @@ assemble_algorithms(ServerOptions *o)
 void
 fill_default_server_options(ServerOptions *options)
 {
 	int i;
 
 	/* Portable-specific options */
 	if (options->use_pam == -1)
 		options->use_pam = 0;
+	if (options->use_pam_check_locks == -1)
+		options->use_pam_check_locks = 0;
 
 	/* Standard Options */
 	if (options->protocol == SSH_PROTO_UNKNOWN)
 		options->protocol = SSH_PROTO_2;
 	if (options->num_host_key_files == 0) {
 		/* fill default hostkeys for protocols */
 		if (options->protocol & SSH_PROTO_1)
 			options->host_key_files[options->num_host_key_files++] =
@@ -391,17 +394,17 @@ fill_default_server_options(ServerOption
 #endif
 
 }
 
 /* Keyword tokens. */
 typedef enum {
 	sBadOption,		/* == unknown option */
 	/* Portable-specific options */
-	sUsePAM,
+	sUsePAM, sUsePAMChecklocks,
 	/* Standard Options */
 	sPort, sHostKeyFile, sServerKeyBits, sLoginGraceTime,
 	sKeyRegenerationTime, sPermitRootLogin, sLogFacility, sLogLevel,
 	sRhostsRSAAuthentication, sRSAAuthentication,
 	sKerberosAuthentication, sKerberosOrLocalPasswd, sKerberosTicketCleanup,
 	sKerberosGetAFSToken,
 	sKerberosTgtPassing, sChallengeResponseAuthentication,
 	sPasswordAuthentication, sKbdInteractiveAuthentication,
@@ -441,18 +444,20 @@ typedef enum {
 static struct {
 	const char *name;
 	ServerOpCodes opcode;
 	u_int flags;
 } keywords[] = {
 	/* Portable-specific options */
 #ifdef USE_PAM
 	{ "usepam", sUsePAM, SSHCFG_GLOBAL },
+	{ "usepamchecklocks", sUsePAMChecklocks, SSHCFG_GLOBAL },
 #else
 	{ "usepam", sUnsupported, SSHCFG_GLOBAL },
+	{ "usepamchecklocks", sUnsupported, SSHCFG_GLOBAL },
 #endif
 	{ "pamauthenticationviakbdint", sDeprecated, SSHCFG_GLOBAL },
 	/* Standard Options */
 	{ "port", sPort, SSHCFG_GLOBAL },
 	{ "hostkey", sHostKeyFile, SSHCFG_GLOBAL },
 	{ "hostdsakey", sHostKeyFile, SSHCFG_GLOBAL },		/* alias */
 	{ "hostkeyagent", sHostKeyAgent, SSHCFG_GLOBAL },
 	{ "pidfile", sPidFile, SSHCFG_GLOBAL },
@@ -1005,16 +1010,19 @@ process_server_config_line(ServerOptions
 		}
 	}
 
 	switch (opcode) {
 	/* Portable-specific options */
 	case sUsePAM:
 		intptr = &options->use_pam;
 		goto parse_flag;
+	case sUsePAMChecklocks:
+		intptr = &options->use_pam_check_locks;
+		goto parse_flag;
 
 	/* Standard Options */
 	case sBadOption:
 		return -1;
 	case sPort:
 		/* ignore ports from configfile if cmdline specifies ports */
 		if (options->ports_from_cmdline)
 			return 0;
diff --git a/openssh-7.2p2/servconf.h b/openssh-7.2p2/servconf.h
--- a/openssh-7.2p2/servconf.h
+++ b/openssh-7.2p2/servconf.h
@@ -167,16 +167,17 @@ typedef struct {
 					 */
 
 	u_int num_authkeys_files;	/* Files containing public keys */
 	char   *authorized_keys_files[MAX_AUTHKEYS_FILES];
 
 	char   *adm_forced_command;
 
 	int	use_pam;		/* Enable auth via PAM */
+	int	use_pam_check_locks;	/* internally check for locked accounts even when using PAM */
 
 	int	permit_tun;
 
 	int	num_permitted_opens;
 
 	char   *chroot_directory;
 	char   *revoked_keys_file;
 	char   *trusted_user_ca_keys;
diff --git a/openssh-7.2p2/sshd_config.0 b/openssh-7.2p2/sshd_config.0
--- a/openssh-7.2p2/sshd_config.0
+++ b/openssh-7.2p2/sshd_config.0
@@ -946,16 +946,24 @@ DESCRIPTION
 
              Because PAM challenge-response authentication usually serves an
              equivalent role to password authentication, you should disable
              either PasswordAuthentication or ChallengeResponseAuthentication.
 
              If UsePAM is enabled, you will not be able to run sshd(8) as a
              non-root user.  The default is M-bM-^@M-^\noM-bM-^@M-^].
 
+     UsePAMCheckLocks
+             When set to ``yes'', the checks whether the account has been
+             locked with `passwd -l' are performed even when PAM authentication
+             is enabled via UsePAM.  This is to ensure that it is not possible
+             to log in with e.g. a public key (in such a case PAM is used only
+             to set up the session and some PAM modules will not check whether
+             the account is locked in this scenario). The default is ``no''.
+
      UsePrivilegeSeparation
              Specifies whether sshd(8) separates privileges by creating an
              unprivileged child process to deal with incoming network traffic.
              After successful authentication, another process will be created
              that has the privilege of the authenticated user.  The goal of
              privilege separation is to prevent privilege escalation by
              containing any corruption within the unprivileged processes.  The
              argument must be M-bM-^@M-^\yesM-bM-^@M-^], M-bM-^@M-^\noM-bM-^@M-^], or M-bM-^@M-^\sandboxM-bM-^@M-^].  If
diff --git a/openssh-7.2p2/sshd_config.5 b/openssh-7.2p2/sshd_config.5
--- a/openssh-7.2p2/sshd_config.5
+++ b/openssh-7.2p2/sshd_config.5
@@ -1578,16 +1578,28 @@ or
 .Pp
 If
 .Cm UsePAM
 is enabled, you will not be able to run
 .Xr sshd 8
 as a non-root user.
 The default is
 .Dq no .
+.It Cm UsePAMCheckLocks
+When set to 
+.Dq yes
+, the checks whether the account has been locked with
+.Pa passwd -l
+are performed even when PAM authentication is enabled via 
+.Cm UsePAM .
+This is to ensure that it is not possible to log in with e.g. a
+public key (in such a case PAM is used only to set up the session and some PAM
+modules will not check whether the account is locked in this scenario). The
+default is 
+.Dq no .
 .It Cm UsePrivilegeSeparation
 Specifies whether
 .Xr sshd 8
 separates privileges by creating an unprivileged child process
 to deal with incoming network traffic.
 After successful authentication, another process will be created that has
 the privilege of the authenticated user.
 The goal of privilege separation is to prevent privilege