s3-auth: Add a way to get an auth4_context from the auth stack

This will allow us to use the same layer that auth_ntlmssp does
in the non-SPNEGO session setup, which will in turn make the
authentication code more consistent in the AD server case.

Andrew Bartlett

4 files changed, 108 insertions, 11 deletions

diff --git a/source3/auth/auth.c b/source3/auth/auth.c
index 1e1ede45a4..1c813a429a 100644
--- a/source3/auth/auth.c
+++ b/source3/auth/auth.c
@@ -460,10 +460,12 @@ static NTSTATUS make_auth_context_text_list(TALLOC_CTX *mem_ctx,
 
 	(*auth_context)->auth_method_list = list;
 
-	/* Look for the first module to provide a start_gensec hook, and set that if provided */
+	/* Look for the first module to provide a prepare_gensec and
+	 * make_auth4_context hook, and set that if provided */
 	for (method = (*auth_context)->auth_method_list; method; method = method->next) {
-		if (method->prepare_gensec) {
+		if (method->prepare_gensec && method->make_auth4_context) {
 			(*auth_context)->prepare_gensec = method->prepare_gensec;
+			(*auth_context)->make_auth4_context = method->make_auth4_context;
 			break;
 		}
 	}
diff --git a/source3/auth/auth_generic.c b/source3/auth/auth_generic.c
index 65b83f035f..681989e16b 100644
--- a/source3/auth/auth_generic.c
+++ b/source3/auth/auth_generic.c
@@ -154,6 +154,54 @@ done:
 	return status;
 }
 
+static struct auth4_context *make_auth4_context_s3(TALLOC_CTX *mem_ctx, struct auth_context *auth_context)
+{
+	struct auth4_context *auth4_context = talloc_zero(mem_ctx, struct auth4_context);
+	if (auth4_context == NULL) {
+		DEBUG(10, ("failed to allocate auth4_context failed\n"));
+		return NULL;
+	}
+	auth4_context->generate_session_info_pac = auth3_generate_session_info_pac;
+	auth4_context->generate_session_info = auth3_generate_session_info;
+	auth4_context->get_challenge = auth3_get_challenge;
+	auth4_context->set_challenge = auth3_set_challenge;
+	auth4_context->challenge_may_be_modified = auth3_may_set_challenge;
+	auth4_context->check_password = auth3_check_password;
+	auth4_context->private_data = talloc_steal(auth4_context, auth_context);
+	return auth4_context;
+}
+
+NTSTATUS make_auth4_context(TALLOC_CTX *mem_ctx, struct auth4_context **auth4_context_out)
+{
+	struct auth_context *auth_context;
+	NTSTATUS nt_status;
+
+	TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
+	NT_STATUS_HAVE_NO_MEMORY(tmp_ctx);
+
+	nt_status = make_auth_context_subsystem(tmp_ctx, &auth_context);
+	if (!NT_STATUS_IS_OK(nt_status)) {
+		TALLOC_FREE(tmp_ctx);
+		return nt_status;
+	}
+
+	if (auth_context->make_auth4_context) {
+		nt_status = auth_context->make_auth4_context(mem_ctx, auth4_context_out);
+		TALLOC_FREE(tmp_ctx);
+		return nt_status;
+
+	} else {
+		struct auth4_context *auth4_context = make_auth4_context_s3(tmp_ctx, auth_context);
+		if (auth4_context == NULL) {
+			TALLOC_FREE(tmp_ctx);
+			return NT_STATUS_NO_MEMORY;
+		}
+		*auth4_context_out = talloc_steal(mem_ctx, auth4_context);
+		TALLOC_FREE(tmp_ctx);
+		return NT_STATUS_OK;
+	}
+}
+
 NTSTATUS auth_generic_prepare(TALLOC_CTX *mem_ctx,
 			      const struct tsocket_address *remote_address,
 			      struct gensec_security **gensec_security_out)
@@ -185,19 +233,11 @@ NTSTATUS auth_generic_prepare(TALLOC_CTX *mem_ctx,
 		struct cli_credentials *server_credentials;
 		const char *dns_name;
 		const char *dns_domain;
-		struct auth4_context *auth4_context = talloc_zero(tmp_ctx, struct auth4_context);
+		struct auth4_context *auth4_context = make_auth4_context_s3(tmp_ctx, auth_context);
 		if (auth4_context == NULL) {
-			DEBUG(10, ("failed to allocate auth4_context failed\n"));
 			TALLOC_FREE(tmp_ctx);
 			return NT_STATUS_NO_MEMORY;
 		}
-		auth4_context->generate_session_info_pac = auth3_generate_session_info_pac;
-		auth4_context->generate_session_info = auth3_generate_session_info;
-		auth4_context->get_challenge = auth3_get_challenge;
-		auth4_context->set_challenge = auth3_set_challenge;
-		auth4_context->challenge_may_be_modified = auth3_may_set_challenge;
-		auth4_context->check_password = auth3_check_password;
-		auth4_context->private_data = talloc_steal(auth4_context, auth_context);
 
 		lp_ctx = loadparm_init_s3(tmp_ctx, loadparm_s3_context());
 		if (lp_ctx == NULL) {
diff --git a/source3/auth/auth_samba4.c b/source3/auth/auth_samba4.c
index 971f9d6898..6692f187be 100644
--- a/source3/auth/auth_samba4.c
+++ b/source3/auth/auth_samba4.c
@@ -169,6 +169,59 @@ static NTSTATUS prepare_gensec(TALLOC_CTX *mem_ctx,
 	return status;
 }
 
+/* Hook to allow handling of NTLM authentication for AD operation
+ * without directly linking the s4 auth stack */
+static NTSTATUS make_auth4_context_s4(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;
+
+	lp_ctx = loadparm_init_s3(frame, loadparm_s3_context());
+	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;
+	}
+
+	msg_ctx = imessaging_client_init(frame,
+					 lp_ctx,
+					 event_ctx);
+	if (msg_ctx == NULL) {
+		DEBUG(1, ("imessaging_init failed\n"));
+		TALLOC_FREE(frame);
+		return NT_STATUS_INVALID_SERVER_STATE;
+	}
+
+	status = auth_context_create(mem_ctx,
+					event_ctx,
+					msg_ctx,
+					lp_ctx,
+					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,
@@ -185,6 +238,7 @@ static NTSTATUS auth_init_samba4(struct auth_context *auth_context,
 	result->name = "samba4";
 	result->auth = check_samba4_security;
 	result->prepare_gensec = prepare_gensec;
+	result->make_auth4_context = make_auth4_context_s4;
 
         *auth_method = result;
 	return NT_STATUS_OK;
diff --git a/source3/auth/proto.h b/source3/auth/proto.h
index 1697eda5be..2d123b0264 100644
--- a/source3/auth/proto.h
+++ b/source3/auth/proto.h
@@ -69,6 +69,7 @@ NTSTATUS auth_netlogond_init(void);
 
 /* The following definitions come from auth/auth_generic.c  */
 
+NTSTATUS make_auth4_context(TALLOC_CTX *mem_ctx, struct auth4_context **auth4_context_out);
 NTSTATUS auth_generic_prepare(TALLOC_CTX *mem_ctx, const struct tsocket_address *remote_address,
 			      struct gensec_security **gensec_security_out);