Adding upstream version 2:4.20.0+dfsg.upstream/2%4.20.0+dfsg

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 401 insertions, 0 deletions

diff --git a/source3/auth/auth_samba4.c b/source3/auth/auth_samba4.c
new file mode 100644
index 0000000..bae34e5
--- /dev/null
+++ b/source3/auth/auth_samba4.c
@@ -0,0 +1,401 @@
+/*
+   Unix SMB/CIFS implementation.
+   Authenticate against Samba4's auth subsystem
+   Copyright (C) Volker Lendecke 2008
+   Copyright (C) Andrew Bartlett 2010
+
+   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 "source3/include/auth.h"
+#include "source3/include/messages.h"
+#include "source4/auth/auth.h"
+#include "auth/auth_sam_reply.h"
+#include "param/param.h"
+#include "source4/lib/events/events.h"
+#include "source4/lib/messaging/messaging.h"
+#include "auth/gensec/gensec.h"
+#include "auth/credentials/credentials.h"
+#include "lib/global_contexts.h"
+#include "lib/util/idtree.h"
+
+#undef DBGC_CLASS
+#define DBGC_CLASS DBGC_AUTH
+
+static NTSTATUS make_auth4_context_s4(const struct auth_context *auth_context,
+				      TALLOC_CTX *mem_ctx,
+				      struct auth4_context **auth4_context);
+
+static struct idr_context *task_id_tree;
+
+static int free_task_id(struct server_id *server_id)
+{
+	idr_remove(task_id_tree, server_id->task_id);
+	return 0;
+}
+
+/* Return a server_id with a unique task_id element.  Free the
+ * returned pointer to de-allocate the task_id via a talloc destructor
+ * (ie, use talloc_free()) */
+static struct server_id *new_server_id_task(TALLOC_CTX *mem_ctx)
+{
+	struct messaging_context *msg_ctx;
+	struct server_id *server_id;
+	int task_id;
+	if (!task_id_tree) {
+		task_id_tree = idr_init(NULL);
+		if (!task_id_tree) {
+			return NULL;
+		}
+	}
+
+	msg_ctx = global_messaging_context();
+	if (msg_ctx == NULL) {
+		return NULL;
+	}
+
+	server_id = talloc(mem_ctx, struct server_id);
+
+	if (!server_id) {
+		return NULL;
+	}
+	*server_id = messaging_server_id(msg_ctx);
+
+	/* 0 is the default server_id, so we need to start with 1 */
+	task_id = idr_get_new_above(task_id_tree, server_id, 1, INT32_MAX);
+
+	if (task_id == -1) {
+		talloc_free(server_id);
+		return NULL;
+	}
+
+	talloc_set_destructor(server_id, free_task_id);
+	server_id->task_id = task_id;
+	return server_id;
+}
+
+/*
+ * This module is not an ordinary authentication module.  It is really
+ * a way to redirect the whole authentication and authorization stack
+ * to use the source4 auth code, not a way to just handle NTLM
+ * authentication.
+ *
+ * See the comments above each function for how that hook changes the
+ * behaviour.
+ */
+
+/* 
+ * This hook is currently used by winbindd only, as all other NTLM
+ * logins go via the hooks provided by make_auth4_context_s4() below.
+ *
+ * This is only left in case we find a way that it might become useful
+ * in future.  Importantly, this routine returns the information
+ * needed for a NETLOGON SamLogon, not what is needed to establish a
+ * session.
+ *
+ * We expect we may use this hook in the source3/ winbind when this
+ * services the AD DC.  It is tested via pdbtest.
+ */
+
+static NTSTATUS check_samba4_security(
+	const struct auth_context *auth_context,
+	void *my_private_data,
+	TALLOC_CTX *mem_ctx,
+	const struct auth_usersupplied_info *user_info,
+	struct auth_serversupplied_info **pserver_info)
+{
+	TALLOC_CTX *frame = talloc_stackframe();
+	struct netr_SamInfo3 *info3 = NULL;
+	NTSTATUS nt_status;
+	struct auth_user_info_dc *user_info_dc;
+	struct auth4_context *auth4_context;
+	uint8_t authoritative = 1;
+	struct auth_serversupplied_info *server_info = NULL;
+
+	nt_status = make_auth4_context_s4(auth_context, mem_ctx, &auth4_context);
+	if (!NT_STATUS_IS_OK(nt_status)) {
+		TALLOC_FREE(frame);
+		goto done;
+	}
+		
+	nt_status = auth_context_set_challenge(auth4_context, auth_context->challenge.data, "auth_samba4");
+	if (!NT_STATUS_IS_OK(nt_status)) {
+		TALLOC_FREE(auth4_context);
+		TALLOC_FREE(frame);
+		return nt_status;
+	}
+
+	nt_status = auth_check_password(auth4_context, auth4_context, user_info,
+					&user_info_dc, &authoritative);
+	if (!NT_STATUS_IS_OK(nt_status)) {
+		if (NT_STATUS_EQUAL(nt_status, NT_STATUS_NO_SUCH_USER) &&
+				    authoritative == 0)
+		{
+			nt_status = NT_STATUS_NOT_IMPLEMENTED;
+		}
+		TALLOC_FREE(auth4_context);
+		TALLOC_FREE(frame);
+		return nt_status;
+	}
+
+	nt_status = auth_convert_user_info_dc_saminfo3(mem_ctx,
+						       user_info_dc,
+						       AUTH_INCLUDE_RESOURCE_GROUPS,
+						       &info3,
+						       NULL);
+	if (NT_STATUS_IS_OK(nt_status)) {
+		/* We need the strings from the server_info to be valid as long as the info3 is around */
+		talloc_steal(info3, user_info_dc);
+	}
+	talloc_free(auth4_context);
+
+	if (!NT_STATUS_IS_OK(nt_status)) {
+		goto done;
+	}
+
+	if (user_info->flags & USER_INFO_INFO3_AND_NO_AUTHZ) {
+		server_info = make_server_info(mem_ctx);
+		if (server_info == NULL) {
+			nt_status = NT_STATUS_NO_MEMORY;
+			goto done;
+		}
+		server_info->info3 = talloc_move(server_info, &info3);
+	} else {
+		nt_status = make_server_info_info3(
+			mem_ctx,
+			user_info->client.account_name,
+			user_info->mapped.domain_name,
+			&server_info,
+			info3);
+		if (!NT_STATUS_IS_OK(nt_status)) {
+			DEBUG(10, ("make_server_info_info3 failed: %s\n",
+				   nt_errstr(nt_status)));
+			goto done;
+		}
+	}
+
+	*pserver_info = server_info;
+	nt_status = NT_STATUS_OK;
+
+ done:
+	TALLOC_FREE(frame);
+	return nt_status;
+}
+
+/*
+ * Hook to allow the source4 set of GENSEC modules to handle
+ * blob-based authentication mechanisms, without directly linking the
+ * mechanism code.
+ *
+ * This may eventually go away, when the GSSAPI acceptors are merged,
+ * when we will just rely on the make_auth4_context_s4 hook instead.
+ *
+ * Even for NTLMSSP, which has a common module, significant parts of
+ * the behaviour are overridden here, because it uses the source4 NTLM
+ * stack and the source4 mapping between the PAC/SamLogon response and
+ * the local token.
+ *
+ * It is important to override all this to ensure that the exact same
+ * token is generated and used in the SMB and LDAP servers, for NTLM
+ * and for Kerberos.
+ */
+static NTSTATUS prepare_gensec(const struct auth_context *auth_context,
+			       TALLOC_CTX *mem_ctx,
+			       struct gensec_security **gensec_context)
+{
+	NTSTATUS status;
+	struct loadparm_context *lp_ctx;
+	struct tevent_context *event_ctx;
+	TALLOC_CTX *frame = talloc_stackframe();
+	struct gensec_security *gensec_ctx;
+	struct imessaging_context *msg_ctx;
+	struct cli_credentials *server_credentials;
+	struct server_id *server_id;
+
+	lp_ctx = loadparm_init_s3(frame, loadparm_s3_helpers());
+	if (lp_ctx == NULL) {
+		DEBUG(1, ("loadparm_init_s3 failed\n"));
+		TALLOC_FREE(frame);
+		return NT_STATUS_INVALID_SERVER_STATE;
+	}
+	event_ctx = s4_event_context_init(frame);
+	if (event_ctx == NULL) {
+		DEBUG(1, ("s4_event_context_init failed\n"));
+		TALLOC_FREE(frame);
+		return NT_STATUS_INVALID_SERVER_STATE;
+	}
+
+	server_id = new_server_id_task(frame);
+	if (server_id == NULL) {
+		DEBUG(1, ("new_server_id_task failed\n"));
+		TALLOC_FREE(frame);
+		return NT_STATUS_INVALID_SERVER_STATE;
+	}
+
+	msg_ctx = imessaging_init_discard_incoming(frame,
+				  lp_ctx,
+				  *server_id,
+				  event_ctx);
+	if (msg_ctx == NULL) {
+		DEBUG(1, ("imessaging_init_discard_incoming failed\n"));
+		TALLOC_FREE(frame);
+		return NT_STATUS_INVALID_SERVER_STATE;
+	}
+
+	talloc_reparent(frame, msg_ctx, server_id);
+
+	server_credentials
+		= cli_credentials_init_server(frame, lp_ctx);
+	if (!server_credentials) {
+		DEBUG(1, ("Failed to init server credentials\n"));
+		TALLOC_FREE(frame);
+		return NT_STATUS_INVALID_SERVER_STATE;
+	}
+
+	status = samba_server_gensec_start(mem_ctx,
+					   event_ctx, msg_ctx,
+					   lp_ctx, server_credentials, "cifs",
+					   &gensec_ctx);
+	if (!NT_STATUS_IS_OK(status)) {
+		DEBUG(1, ("Failed to start GENSEC server code: %s\n", nt_errstr(status)));
+		TALLOC_FREE(frame);
+		return status;
+	}
+
+	talloc_reparent(frame, gensec_ctx, msg_ctx);
+	talloc_reparent(frame, gensec_ctx, event_ctx);
+	talloc_reparent(frame, gensec_ctx, lp_ctx);
+	talloc_reparent(frame, gensec_ctx, server_credentials);
+
+	gensec_want_feature(gensec_ctx, GENSEC_FEATURE_SESSION_KEY);
+	gensec_want_feature(gensec_ctx, GENSEC_FEATURE_UNIX_TOKEN);
+
+	*gensec_context = gensec_ctx;
+	TALLOC_FREE(frame);
+	return status;
+}
+
+/*
+ * Hook to allow handling of NTLM authentication for AD operation
+ * without directly linking the s4 auth stack
+ *
+ * This ensures we use the source4 authentication stack, as well as
+ * the authorization stack to create the user's token.  This ensures
+ * consistency between NTLM logins and NTLMSSP logins, as NTLMSSP is
+ * handled by the hook above.
+ */
+static NTSTATUS make_auth4_context_s4(const struct auth_context *auth_context,
+				      TALLOC_CTX *mem_ctx,
+				      struct auth4_context **auth4_context)
+{
+	NTSTATUS status;
+	struct loadparm_context *lp_ctx;
+	struct tevent_context *event_ctx;
+	TALLOC_CTX *frame = talloc_stackframe();
+	struct imessaging_context *msg_ctx;
+	struct server_id *server_id;
+
+	lp_ctx = loadparm_init_s3(frame, loadparm_s3_helpers());
+	if (lp_ctx == NULL) {
+		DEBUG(1, ("loadparm_init_s3 failed\n"));
+		TALLOC_FREE(frame);
+		return NT_STATUS_INVALID_SERVER_STATE;
+	}
+	event_ctx = s4_event_context_init(frame);
+	if (event_ctx == NULL) {
+		DEBUG(1, ("s4_event_context_init failed\n"));
+		TALLOC_FREE(frame);
+		return NT_STATUS_INVALID_SERVER_STATE;
+	}
+
+	server_id = new_server_id_task(frame);
+	if (server_id == NULL) {
+		DEBUG(1, ("new_server_id_task failed\n"));
+		TALLOC_FREE(frame);
+		return NT_STATUS_INVALID_SERVER_STATE;
+	}
+
+	msg_ctx = imessaging_init_discard_incoming(frame,
+				  lp_ctx,
+				  *server_id,
+				  event_ctx);
+	if (msg_ctx == NULL) {
+		DEBUG(1, ("imessaging_init_discard_incoming failed\n"));
+		TALLOC_FREE(frame);
+		return NT_STATUS_INVALID_SERVER_STATE;
+	}
+	talloc_reparent(frame, msg_ctx, server_id);
+
+	/* Allow forcing a specific auth4 module */
+	if (!auth_context->forced_samba4_methods) {
+		status = auth_context_create(mem_ctx,
+					     event_ctx,
+					     msg_ctx,
+					     lp_ctx,
+					     auth4_context);
+	} else {
+		const char * const *forced_auth_methods = (const char * const *)str_list_make(mem_ctx, auth_context->forced_samba4_methods, NULL);
+		status = auth_context_create_methods(mem_ctx, forced_auth_methods, event_ctx, msg_ctx, lp_ctx, NULL, auth4_context);
+	}
+	if (!NT_STATUS_IS_OK(status)) {
+		DEBUG(1, ("Failed to start auth server code: %s\n", nt_errstr(status)));
+		TALLOC_FREE(frame);
+		return status;
+	}
+
+	talloc_reparent(frame, *auth4_context, msg_ctx);
+	talloc_reparent(frame, *auth4_context, event_ctx);
+	talloc_reparent(frame, *auth4_context, lp_ctx);
+
+	TALLOC_FREE(frame);
+	return status;
+}
+
+/* module initialisation */
+static NTSTATUS auth_init_samba4(struct auth_context *auth_context,
+				 const char *param,
+				 struct auth_methods **auth_method)
+{
+	struct auth_methods *result;
+
+	gensec_init();
+
+	result = talloc_zero(auth_context, struct auth_methods);
+	if (result == NULL) {
+		return NT_STATUS_NO_MEMORY;
+	}
+	result->name = "samba4";
+	result->auth = check_samba4_security;
+	result->prepare_gensec = prepare_gensec;
+	result->make_auth4_context = make_auth4_context_s4;
+
+	if (param && *param) {
+		auth_context->forced_samba4_methods = talloc_strdup(result, param);
+		if (!auth_context->forced_samba4_methods) {
+			return NT_STATUS_NO_MEMORY;
+		}
+	}
+
+        *auth_method = result;
+	return NT_STATUS_OK;
+}
+
+NTSTATUS auth_samba4_init(TALLOC_CTX *mem_ctx);
+NTSTATUS auth_samba4_init(TALLOC_CTX *mem_ctx)
+{
+	smb_register_auth(AUTH_INTERFACE_VERSION, "samba4",
+			  auth_init_samba4);
+	return NT_STATUS_OK;
+}