Add custom Grant

components/identity-extensions/io.entgra.device.mgt.core.device.mgt.oauth.extensions/src/main/java/io/entgra/device/mgt/core/device/mgt/oauth/extensions/handlers/grant/DeviceGrantHandler.java

@@ -0,0 +1,95 @@
+/*
+ * Copyright (c) 2018 - 2023, Entgra (Pvt) Ltd. (http://www.entgra.io) All Rights Reserved.
+ *
+ * Entgra (Pvt) Ltd. licenses this file to you under the Apache License,
+ * Version 2.0 (the "License"); you may not use this file except
+ * in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package io.entgra.device.mgt.core.device.mgt.oauth.extensions.handlers.grant;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import org.wso2.carbon.identity.application.authentication.framework.model.AuthenticatedUser;
+import org.wso2.carbon.identity.oauth2.IdentityOAuth2Exception;
+import org.wso2.carbon.identity.oauth2.model.RequestParameter;
+import org.wso2.carbon.identity.oauth2.token.OAuthTokenReqMessageContext;
+import org.wso2.carbon.identity.oauth2.token.handlers.grant.AbstractAuthorizationGrantHandler;
+
+public class DeviceGrantHandler extends AbstractAuthorizationGrantHandler{
+
+    private static final Log log = LogFactory.getLog(DeviceGrantHandler.class);
+
+    public static final String MOBILE_NUMBER = "mobile_number";
+    public static final String ID_TOKEN_HINT = "id_token_hint";
+
+    @Override
+    public boolean validateGrant(OAuthTokenReqMessageContext tokReqMsgCtx)  throws IdentityOAuth2Exception {
+        boolean validateGrant = super.validateGrant(tokReqMsgCtx);
+
+        if (validateGrant){
+            RequestParameter[] parameters = tokReqMsgCtx.getOauth2AccessTokenReqDTO().getRequestParameters();
+
+            String mobileNumber = null;
+            String userID = null;
+            String idTokenHint = null;
+
+            for (RequestParameter parameter : parameters) {
+                if (MOBILE_NUMBER.equals(parameter.getKey())) {
+                    if (parameter.getValue() != null && parameter.getValue().length > 0) {
+                        mobileNumber = parameter.getValue()[0];
+                    }
+                }
+                if (ID_TOKEN_HINT.equals(parameter.getKey())) {
+                    if (parameter.getValue() != null && parameter.getValue().length > 0) {
+                        idTokenHint = parameter.getValue()[0];
+                    }
+                }
+            }
+
+            if (mobileNumber != null && idTokenHint != null && isValidMobileNumber(mobileNumber)){
+                AuthenticatedUser mobileUser = new AuthenticatedUser();
+                mobileUser.setUserId("userID");
+                mobileUser.setUserName(mobileNumber);
+                mobileUser.setAuthenticatedSubjectIdentifier(mobileNumber);
+                mobileUser.setFederatedUser(false);
+                mobileUser.setTenantDomain("carbon.super");
+                mobileUser.setUserStoreDomain("PRIMARY");
+                tokReqMsgCtx.setAuthorizedUser(mobileUser);
+                tokReqMsgCtx.setScope(tokReqMsgCtx.getOauth2AccessTokenReqDTO().getScope());
+
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    /**
+     *
+     * This method should be implemented as per requirement
+     *
+     * @param mobileNumber
+     * @return
+     */
+    private boolean isValidMobileNumber(String mobileNumber){
+
+        // just demo validation
+
+        if(mobileNumber.startsWith("011")){
+            return true;
+        }
+
+        return false;
+    }
+}

components/identity-extensions/io.entgra.device.mgt.core.device.mgt.oauth.extensions/src/main/java/io/entgra/device/mgt/core/device/mgt/oauth/extensions/handlers/grant/oauth/validator/DeviceGrantValidator.java

@@ -0,0 +1,29 @@
+/*
+ * Copyright (c) 2018 - 2023, Entgra (Pvt) Ltd. (http://www.entgra.io) All Rights Reserved.
+ *
+ * Entgra (Pvt) Ltd. licenses this file to you under the Apache License,
+ * Version 2.0 (the "License"); you may not use this file except
+ * in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package io.entgra.device.mgt.core.device.mgt.oauth.extensions.handlers.grant.oauth.validator;
+
+import org.apache.oltu.oauth2.common.validators.AbstractValidator;
+
+public class DeviceGrantValidator extends AbstractValidator {
+
+    public DeviceGrantValidator() {
+        requiredParams.add("mobile_number");
+        requiredParams.add("id_token_hint");
+    }
+}