openapi: 3.0.3 info: title: Call Forwarding Signal Age Verification Discovery API description: '# Overview The Call Forwarding Signal API provides the API Consumer with information about the status of the Call Forwarding Service on a specific phone number. The main scope of the Call Forwarding Signal API is "anti Fraud" to avoid fraudsters to use the Call Forwarding Service to carry on a scam. Other use cases are anyway supported by the Call Forwarding Signal API that also provides additional endpoints to detect the general Call Forwarding Service settings. # Introduction The Call Forwarding Service is provided by the Network to a phone number. This service redirects the incoming call to that phone number to an alternative destination such as another phone number or a voice mail system. There are two main types of call forwarding settings: unconditional and conditional. The Call Forwarding Signal API can be invoked to detect if the unconditional call forwarding service is active. The Call Forwarding Signal API can also be invoked to get the general status of the Call Forwarding Service (inactive, conditional, unconditional). If conditional call forwarding is active, the different type of settings are returned (''conditional_busy'', ''conditional_not_reachable'', ''conditional_no_answer''). **Example use cases:** [**Bank Frauds**](https://github.com/camaraproject/CallForwardingSignal/discussions/3#discussioncomment-8694420) [**Alert Interception**](https://github.com/camaraproject/CallForwardingSignal/discussions/3#discussioncomment-8701847) [**Call Forwarding Verification**](https://github.com/camaraproject/CallForwarding\Signal/discussions/3#discussioncomment-8915595) # Quick Start The Call Forwarding Signal API is a REST API based on the CreateCallForwardingSignal resource. This resource can be used, by the API Consumer, to specify the phone number on which the Call Forwarding Service status must be verified, in case of two-legged authentication. If three-legged authentication is used the phone number is instead detected, by the API Producer, from the access token. Before starting to use the Call Forwarding API, the developer needs to know about the below specified details: **phoneNumber** This is the end user phone number. The Call Forwarding Signal API verifies if a call forwarding service is active on this phone number. Note: this parameter must be must be provided/valued only in case of two-legged authentication. In case of three-legged authentication the phone number is retrieved by the access token. **CreateCallForwardingSignal** This is the resource the API Consumer uses to define the phone number to be verified about the status of the Network Call Forwarding service. **UnconditionalCallForwardingSignal** This is the resource the API Consumer gets back, containing the information about the Unconditional Call Forwarding Service status for the given phone number (PhoneNumber). **CallForwardingSignal** This is the resource the API Consumer gets back, containing the information about the general status of the Network Call Forwarding service for the specified phone number. The Call Forwarding Signal API provides two endpoints fulfilling the following intents: - **unconditional-call-forwardings**: Is the unconditional call fwd service active on a specific phone number? - **call-forwardings**: Which is the status of the call forwarding for a specific phone number? # API Documentation ## Details The Call Forwarding Signal API is invoked by an API Consumer after the Consent Management flow. The API Consumer can request the API Producer for the status of the Unconditional Call Forwarding service using the unconditional-call-forwardings POST method. A boolean, with the information about the activation status of the call forwarding service, will be provided back via the UnconditionalCallForwardingSignal resource. The API Consumer can also request the API Producer for the generic status of the Call Forwarding service using the call-forwardings POST method. An array of strings with the information of the type of active call forwarding services will be provided back via the CallForwardingSignal resource. # Authorization and authentication The "Camara Security and Interoperability Profile" provides details of how an API consumer requests an access token. Please refer to Identity and Consent Management (https://github.com/camaraproject/IdentityAndConsentManagement/) for the released version of the profile. The specific authorization flows to be used will be agreed upon during the onboarding process, happening between the API consumer and the API provider, taking into account the declared purpose for accessing the API, whilst also being subject to the prevailing legal framework dictated by local legislation. In cases where personal data is processed by the API and users can exercise their rights through mechanisms such as opt-in and/or opt-out, the use of three-legged access tokens is mandatory. This ensures that the API remains in compliance with privacy regulations, upholding the principles of transparency and user-centric privacy-by-design. # Identifying the phone number from the access token This API requires the API consumer to identify a phone number as the subject of the API as follows: - When the API is invoked using a two-legged access token, the subject will be identified from the optional `phoneNumber` object field, which therefore MUST be provided. - When a three-legged access token is used however, this optional identifier MUST NOT be provided, as the subject will be uniquely identified from the access token. This approach simplifies API usage for API consumers using a three-legged access token to invoke the API by relying on the information that is associated with the access token and was identified during the authentication process. ## Error handling: - If the subject cannot be identified from the access token and the optional `phoneNumber` object field is not included in the request, then the server will return an error with the `422 MISSING_IDENTIFIER` error code. - If the subject can be identified from the access token and the optional `phoneNumber` object field is also included in the request, then the server will return an error with the `422 UNNECESSARY_IDENTIFIER` error code. This will be the case even if the same device is identified by these two methods, as the server is unable to make this comparison. # Additional CAMARA error responses The list of error codes in this API specification is not exhaustive. Therefore the API specification may not document some non-mandatory error statuses as indicated in `CAMARA API Design Guide`. Please refer to the `CAMARA_common.yaml` of the Commonalities Release associated to this API version for a complete list of error responses. The applicable Commonalities Release can be identified in the `API Readiness Checklist` document associated to this API version. As a specific rule, error `501 - NOT_IMPLEMENTED` can be only a possible error response if it is explicitly documented in the API. # FAQ''s (FAQs will be added in a later version of the documentation) ' version: wip license: name: Apache 2.0 url: https://www.apache.org/licenses/LICENSE-2.0.html x-camara-commonalities: 0.6 servers: - url: '{apiRoot}/call-forwarding-signal/vwip' variables: apiRoot: default: http://localhost:9091 description: API root, defined by the service provider, e.g. `api.example.com` or `api.example.com/somepath` tags: - name: Discovery description: 'Find the closest Edge Cloud Zone to the user device. ' paths: /retrieve-closest-edge-cloud-zone: post: security: - openId: - simple-edge-discovery:read operationId: readClosestEdgeCloudZone parameters: - in: header name: x-correlator description: Correlation id for the different services required: false schema: $ref: '#/components/schemas/XCorrelator' requestBody: description: Parameters to create a new session required: true content: application/json: schema: $ref: '#/components/schemas/RequestBody' examples: Identify Device By 3-Legged Access Token: $ref: '#/components/examples/IdentifyDeviceBy3LeggedToken' Identify Device By Phone Number: $ref: '#/components/examples/IdentifyDeviceByPhoneNumber' Identify Device By IP Address: $ref: '#/components/examples/IdentifyDeviceByIPAddress' Identify Device By Multiple Identifiers: $ref: '#/components/examples/IdentifyDeviceByMultipleIdentifiers' responses: '200': $ref: '#/components/responses/200Success' '400': $ref: '#/components/responses/Generic400' '401': $ref: '#/components/responses/Generic401' '403': $ref: '#/components/responses/Generic403' '404': $ref: '#/components/responses/Generic404' '422': $ref: '#/components/responses/Generic422' '429': $ref: '#/components/responses/Generic429' tags: - Discovery summary: 'Returns the name of the Edge Cloud Zone closest to user device identified in the request. ' description: 'On receiving this request, the network will return the name of the Edge Cloud Zone with the shortest network path to the end user device identified in the request. ' components: examples: IdentifyDeviceByPhoneNumber: description: Identifying device by phone number value: device: phoneNumber: '+123456789' IdentifyDeviceByIPAddress: description: Identifying device by IP address value: device: ipv4Address: publicAddress: 84.125.93.10 publicPort: 59765 IdentifyDeviceByMultipleIdentifiers: description: Identifying device by multiple device identifiers value: device: phoneNumber: '+123456789' ipv4Address: publicAddress: 84.125.93.10 publicPort: 59765 networkAccessIdentifier: 123456789@domain.com IdentifyDeviceBy3LeggedToken: description: Empty JSON when device is identified by access token value: {} schemas: EdgeCloudZoneId: description: 'Operator-issued UUID for the Edge Cloud Zone. ' type: string format: uuid additionalProperties: false EdgeCloudProvider: description: 'The company name of the Edge Cloud Zone provider. ' type: string SingleIpv4Addr: description: A single IPv4 address with no subnet mask type: string format: ipv4 example: 84.125.93.10 DeviceResponse: description: 'An identifier for the end-user equipment able to connect to the network that the response refers to. This parameter is only returned when the API consumer includes the `device` parameter in their request (i.e. they are using a two-legged access token), and is relevant when more than one device identifier is specified, as only one of those device identifiers is allowed in the response. If the API consumer provides more than one device identifier in their request, the API provider must return a single identifier which is the one they are using to fulfil the request, even if the identifiers do not match the same device. API provider does not perform any logic to validate/correlate that the indicated device identifiers match the same device. No error should be returned if the identifiers are otherwise valid to prevent API consumers correlating different identifiers with a given end user. ' allOf: - $ref: '#/components/schemas/Device' - maxProperties: 1 DeviceResponseBody: description: 'The optional device identifier to include in the response ' properties: device: description: 'The device identifier that was used to fulfil the request. If this property is not present then the device identifier sent in the request was used. ' allOf: - $ref: '#/components/schemas/DeviceResponse' - example: phoneNumber: '+123456789' XCorrelator: type: string pattern: ^[a-zA-Z0-9-_:;.\/<>{}]{0,256}$ example: b4333c46-49c0-4f62-80d7-f0ef930f1c46 PhoneNumber: description: 'A public identifier addressing a telephone subscription. In mobile networks it corresponds to the MSISDN (Mobile Station International Subscriber Directory Number). In order to be globally unique it has to be formatted in international format, according to E.164 standard, prefixed with ''+''. ' type: string pattern: ^\+[1-9][0-9]{4,14}$ example: '+123456789' DeviceIpv4Addr: type: object description: 'The device should be identified by either the public (observed) IP address and port as seen by the application server, or the private (local) and any public (observed) IP addresses in use by the device (this information can be obtained by various means, for example from some DNS servers). If the allocated and observed IP addresses are the same (i.e. NAT is not in use) then the same address should be specified for both publicAddress and privateAddress. If NAT64 is in use, the device should be identified by its publicAddress and publicPort, or separately by its allocated IPv6 address (field ipv6Address of the Device object) In all cases, publicAddress must be specified, along with at least one of either privateAddress or publicPort, dependent upon which is known. In general, mobile devices cannot be identified by their public IPv4 address alone. ' properties: publicAddress: $ref: '#/components/schemas/SingleIpv4Addr' privateAddress: $ref: '#/components/schemas/SingleIpv4Addr' publicPort: $ref: '#/components/schemas/Port' anyOf: - required: - publicAddress - privateAddress - required: - publicAddress - publicPort example: publicAddress: 84.125.93.10 publicPort: 59765 EdgeCloudZoneName: description: 'Edge Cloud Zone Name - the common name for the Edge Cloud Zone. ' type: string additionalProperties: false ErrorInfo: type: object description: Error information required: - status - code - message properties: status: type: integer description: HTTP response status code code: type: string description: Friendly Code to describe the error message: type: string description: A human readable description of what the event represents DeviceIpv6Address: description: 'The device should be identified by the observed IPv6 address, or by any single IPv6 address from within the subnet allocated to the device (e.g. adding ::0 to the /64 prefix). ' type: string format: ipv6 example: 2001:db8:85a3:8d3:1319:8a2e:370:7344 EdgeCloudZone: type: object description: 'An Edge Cloud Zone, uniquely identified by a combination of the value of the Edge Resource Name object and the value of the Provider object (the name of the cloud provider or operator hosting that edge cloud zone). ' properties: edgeCloudZoneId: $ref: '#/components/schemas/EdgeCloudZoneId' edgeCloudZoneName: $ref: '#/components/schemas/EdgeCloudZoneName' edgeCloudProvider: $ref: '#/components/schemas/EdgeCloudProvider' required: - edgeCloudZoneId - edgeCloudZoneName - edgeCloudProvider Port: description: TCP or UDP port number type: integer minimum: 1024 maximum: 65535 Device: description: 'End-user equipment able to connect to a mobile network. Examples of devices include smartphones or IoT sensors/actuators. The developer can choose to provide the below specified device identifiers: * `ipv4Address` * `ipv6Address` * `phoneNumber` * `networkAccessIdentifier` NOTE 1: the MNO might support only a subset of these options. The API invoker can provide multiple identifiers to be compatible across different MNOs. In this case the identifiers MUST belong to the same device. NOTE 2: as for this Commonalities release, we are enforcing that the networkAccessIdentifier is only part of the schema for future-proofing, and CAMARA does not currently allow its use. After the CAMARA meta-release work is concluded and the relevant issues are resolved, its use will need to be explicitly documented in the guidelines. ' type: object properties: phoneNumber: $ref: '#/components/schemas/PhoneNumber' networkAccessIdentifier: $ref: '#/components/schemas/NetworkAccessIdentifier' ipv4Address: $ref: '#/components/schemas/DeviceIpv4Addr' ipv6Address: $ref: '#/components/schemas/DeviceIpv6Address' minProperties: 1 NetworkAccessIdentifier: description: 'A public identifier addressing a subscription in a mobile network. In 3GPP terminology, it corresponds to the GPSI formatted with the External Identifier ({Local Identifier}@{Domain Identifier}). Unlike the telephone number, the network access identifier is not subjected to portability ruling in force, and is individually managed by each operator. ' type: string example: 123456789@domain.com RequestBody: description: Common request body to allow optional Device object to be passed type: object properties: device: $ref: '#/components/schemas/Device' responses: Generic422: description: Unprocessable Content headers: x-correlator: $ref: '#/components/headers/x-correlator' content: application/json: schema: allOf: - $ref: '#/components/schemas/ErrorInfo' - type: object properties: status: enum: - 422 code: enum: - SERVICE_NOT_APPLICABLE - MISSING_IDENTIFIER - UNSUPPORTED_IDENTIFIER - UNNECESSARY_IDENTIFIER examples: GENERIC_422_SERVICE_NOT_APPLICABLE: description: Service not applicable for the provided identifier value: status: 422 code: SERVICE_NOT_APPLICABLE message: The service is not available for the provided identifier. GENERIC_422_MISSING_IDENTIFIER: description: An identifier is not included in the request and the device or phone number identification cannot be derived from the 3-legged access token value: status: 422 code: MISSING_IDENTIFIER message: The device cannot be identified. GENERIC_422_UNSUPPORTED_IDENTIFIER: description: None of the provided identifiers is supported by the implementation value: status: 422 code: UNSUPPORTED_IDENTIFIER message: The identifier provided is not supported. GENERIC_422_UNNECESSARY_IDENTIFIER: description: An explicit identifier is provided when a device or phone number has already been identified from the access token value: status: 422 code: UNNECESSARY_IDENTIFIER message: The device is already identified by the access token. Generic429: description: Too Many Requests headers: x-correlator: $ref: '#/components/headers/x-correlator' content: application/json: schema: allOf: - $ref: '#/components/schemas/ErrorInfo' - type: object properties: status: enum: - 429 code: enum: - QUOTA_EXCEEDED - TOO_MANY_REQUESTS examples: GENERIC_429_QUOTA_EXCEEDED: description: Request is rejected due to exceeding a business quota limit value: status: 429 code: QUOTA_EXCEEDED message: Out of resource quota. GENERIC_429_TOO_MANY_REQUESTS: description: Access to the API has been temporarily blocked due to rate or spike arrest limits being reached. value: status: 429 code: TOO_MANY_REQUESTS message: Rate limit reached. Generic400: description: Bad Request headers: x-correlator: $ref: '#/components/headers/x-correlator' content: application/json: schema: allOf: - $ref: '#/components/schemas/ErrorInfo' - type: object properties: status: enum: - 400 code: enum: - INVALID_ARGUMENT - OUT_OF_RANGE examples: GENERIC_400_INVALID_ARGUMENT: description: Invalid Argument. Generic Syntax Exception value: status: 400 code: INVALID_ARGUMENT message: Client specified an invalid argument, request body or query param. GENERIC_400_OUT_OF_RANGE: description: Out of Range. Specific Syntax Exception used when a given field has a pre-defined range or a invalid filter criteria combination is requested value: status: 400 code: OUT_OF_RANGE message: Client specified an invalid range. Generic401: description: Unauthorized headers: x-correlator: $ref: '#/components/headers/x-correlator' content: application/json: schema: allOf: - $ref: '#/components/schemas/ErrorInfo' - type: object properties: status: enum: - 401 code: enum: - UNAUTHENTICATED - AUTHENTICATION_REQUIRED examples: GENERIC_401_UNAUTHENTICATED: description: Request cannot be authenticated value: status: 401 code: UNAUTHENTICATED message: Request not authenticated due to missing, invalid, or expired credentials. Generic403: description: Forbidden headers: x-correlator: $ref: '#/components/headers/x-correlator' content: application/json: schema: allOf: - $ref: '#/components/schemas/ErrorInfo' - type: object properties: status: enum: - 403 code: enum: - PERMISSION_DENIED - INVALID_TOKEN_CONTEXT examples: GENERIC_403_PERMISSION_DENIED: description: Permission denied. OAuth2 token access does not have the required scope or when the user fails operational security value: status: 403 code: PERMISSION_DENIED message: Client does not have sufficient permissions to perform this action. GENERIC_403_INVALID_TOKEN_CONTEXT: description: Reflect some inconsistency between information in some field of the API and the related OAuth2 Token value: status: 403 code: INVALID_TOKEN_CONTEXT message: '{{field}} is not consistent with access token.' Generic404: description: Not found headers: x-correlator: $ref: '#/components/headers/x-correlator' content: application/json: schema: allOf: - $ref: '#/components/schemas/ErrorInfo' - type: object properties: status: enum: - 404 code: enum: - NOT_FOUND - IDENTIFIER_NOT_FOUND examples: GENERIC_404_NOT_FOUND: description: Resource is not found value: status: 404 code: NOT_FOUND message: The specified resource is not found. GENERIC_404_IDENTIFIER_NOT_FOUND: description: Some identifier cannot be matched to a device value: status: 404 code: IDENTIFIER_NOT_FOUND message: Device identifier not found. 200Success: description: 200 OK headers: x-correlator: $ref: '#/components/headers/x-correlator' content: application/json: schema: required: - edgeCloudZoneId - edgeCloudZoneName - edgeCloudProvider allOf: - $ref: '#/components/schemas/EdgeCloudZone' - $ref: '#/components/schemas/DeviceResponseBody' examples: Closest Edge Cloud details: description: The details of the closest Edge Cloud Zone value: edgeCloudZoneId: f81d4fae-7dec-11d0-a765-00a0c91e6bf6 edgeCloudZoneName: UK-SOUTH edgeCloudProvider: Example Provider Closest Edge Cloud plus device identifier: description: The details of the closest Edge Cloud Zone and the device identifier used to fulfill the request value: edgeCloudZoneId: f81d4fae-7dec-11d0-a765-00a0c91e6bf6 edgeCloudZoneName: UK-SOUTH edgeCloudProvider: Example Provider device: phoneNumber: '+123456789' headers: x-correlator: description: Correlation id for the different services required: false schema: $ref: '#/components/schemas/XCorrelator' securitySchemes: openId: description: to support Consent Management type: openIdConnect openIdConnectUrl: https://example.com/.well-known/openid-configuration externalDocs: description: Product documentation at CAMARA url: https://github.com/camaraproject/CallForwardingSignal