Add SASL/EXTERNAL gensec module

Signed-off-by: Howard Chu <hyc@symas.com>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>
Reviewed-by: Nadezhda Ivanova <nivanova@symas.com>

3 files changed, 91 insertions, 1 deletions

diff --git a/auth/gensec/external.c b/auth/gensec/external.c
new file mode 100644
index 0000000000..a26e435319
--- /dev/null
+++ b/auth/gensec/external.c
@@ -0,0 +1,82 @@
+/*
+   Unix SMB/CIFS implementation.
+
+   SASL/EXTERNAL authentication.
+
+   Copyright (C) Howard Chu <hyc@symas.com> 2013
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "includes.h"
+#include "auth/credentials/credentials.h"
+#include "auth/gensec/gensec.h"
+#include "auth/gensec/gensec_internal.h"
+#include "auth/gensec/gensec_proto.h"
+#include "auth/gensec/gensec_toplevel_proto.h"
+
+/* SASL/EXTERNAL is essentially a no-op; it is only usable when the transport
+ * layer is already mutually authenticated.
+ */
+
+NTSTATUS gensec_external_init(void);
+
+static NTSTATUS gensec_external_start(struct gensec_security *gensec_security)
+{
+	if (gensec_security->want_features & GENSEC_FEATURE_SIGN)
+		return NT_STATUS_INVALID_PARAMETER;
+	if (gensec_security->want_features & GENSEC_FEATURE_SEAL)
+		return NT_STATUS_INVALID_PARAMETER;
+
+	return NT_STATUS_OK;
+}
+
+static NTSTATUS gensec_external_update(struct gensec_security *gensec_security,
+				   TALLOC_CTX *out_mem_ctx,
+				   struct tevent_context *ev,
+				   const DATA_BLOB in, DATA_BLOB *out)
+{
+	*out = data_blob_talloc(out_mem_ctx, "", 0);
+	return NT_STATUS_OK;
+}
+
+/* We have no features */
+static bool gensec_external_have_feature(struct gensec_security *gensec_security,
+				     uint32_t feature)
+{
+	return false;
+}
+
+static const struct gensec_security_ops gensec_external_ops = {
+	.name             = "sasl-EXTERNAL",
+	.sasl_name        = "EXTERNAL",
+	.client_start     = gensec_external_start,
+	.update 	  = gensec_external_update,
+	.have_feature     = gensec_external_have_feature,
+	.enabled          = true,
+	.priority         = GENSEC_EXTERNAL
+};
+
+
+NTSTATUS gensec_external_init(void)
+{
+	NTSTATUS ret;
+
+	ret = gensec_register(&gensec_external_ops);
+	if (!NT_STATUS_IS_OK(ret)) {
+		DEBUG(0,("Failed to register '%s' gensec backend!\n",
+			 gensec_external_ops.name));
+	}
+	return ret;
+}
diff --git a/auth/gensec/gensec.h b/auth/gensec/gensec.h
index ac1fadfeef..6974f8708b 100644
--- a/auth/gensec/gensec.h
+++ b/auth/gensec/gensec.h
@@ -41,7 +41,8 @@ enum gensec_priority {
 	GENSEC_SCHANNEL = 60,
 	GENSEC_NTLMSSP = 50,
 	GENSEC_SASL = 20,
-	GENSEC_OTHER = 0
+	GENSEC_OTHER = 10,
+	GENSEC_EXTERNAL = 0
 };
 
 struct gensec_security;
diff --git a/auth/gensec/wscript_build b/auth/gensec/wscript_build
index fcd74a3a9d..71222f7b26 100755
--- a/auth/gensec/wscript_build
+++ b/auth/gensec/wscript_build
@@ -16,3 +16,10 @@ bld.SAMBA_MODULE('gensec_spnego',
 	init_function='gensec_spnego_init',
 	deps='asn1util samba-credentials SPNEGO_PARSE'
 	)
+
+bld.SAMBA_MODULE('gensec_external',
+	source='external.c',
+	autoproto='external_proto.h',
+	subsystem='gensec',
+	init_function='gensec_external_init'
+	)