MDS Specification

MDS Specification

Introduction & Background

Objective

The objective of this specification document is to establish the technical and compliance standards/ protocols that are necessary for a biometric device to be used in MOSIP solutions.

Target Audience

This is a biometric device specification document and aims to help the biometric device manufacturers, their developers, and their designers in building MOSIP-compliant devices. It is assumed that the readers are familiar with MOSIP registration and authentication services.

MOSIP Devices

All devices that collect biometric data for MOSIP should operate within the specification of this document.

Revision History

Version	State	Date	Changes
0.9.2	Frozen	Aug-2019
0.9.3	Frozen	Feb-2020
0.9.5	Draft	13-Jun-2020
0.9.5	Draft	10-Aug-2020	Signature for API to retrieve encryption certificate has been changed from GET to POST and Device Stream now supports an optional parameter - timeout
0.9.5	Draft	04-Dec-2020	In the header of JWT Signature, the key to store the type has been changed to "typ" from "type" as per JWT standards. Kindly view the digital id specification for the change.
0.9.5	Draft	26-Feb-2021	Updated the FTM criteria to include PCI PED 2.0 and CC.
0.9.5	Draft	24-Mar-2021	The reference to L2 devices has been removed from this document. The biometric specification listed here has been moved to a new section Biometric Specification and the old specification is now in 0.9.5 Biometric Specifications for reference.
0.9.5	Draft	07-Apr-2021	Device De registration API spec was updated.
0.9.5	Draft	08-Apr-2021	We will be following datetime values in ISO 8601 with format yyyy-mm-ddTHH:MM:ssZ. The same has been updated throughout the document.
0.9.5	Draft	24-May-2021	Clarification on hash and previousHash definition has been provided
0.9.5	Draft	04-Apr-2022	Register and De-register of devices have been removed from MOSIP. Device validation in MOSIP will be done via cryptography. Here onwards, registering a device will mean a device obtaining a certificate from the management server.
0.9.5	Draft	27-Jul-2022	Added the section on Android SBI Specification
0.9.5	Draft	24-Oct-2023	Added error code for devices in busy or not ready state. Also added validation for transactionID in request parameters.

Glossary of Terms

• Device Provider - An entity that manufactures or imports the devices in their name. This entity should have legal rights to obtain an organization-level digital certificate from the respective authority in the country.

• FTM Provider - An entity that manufactures or guarantees the trustworthiness of the foundational trust module. This can be the device provider as well.

• Device - A hardware capable of capturing biometric information.

• L1 Certified Device / L1 Device - A device certified as capable of performing encryption in line with this spec in its trusted zone.

• L0 Certified Device / L0 Device - A device certified as one where the encryption is done on the host machine device driver or the MOSIP device service.

• FTM Provider Certificate - A digital certificate issued to the "Foundational Trust Provider". This certificate proves that the provider has successfully gone through the required Foundational Trust Provider evaluation. The entity is expected to keep this certificate in secure possession in an HSM. All the individual FTM trust certificates are issued using this certificate as the root. This certificate would be issued by the countries in conjunction with MOSIP.

• Device Provider Certificate - A digital certificate issued to the "Device Provider". This certificate proves that the provider has been certified for L0/L1 respective compliance. The entity is expected to keep this certificate in secure possession in an HSM. All the individual trust certificates are issued using this certificate as the root. This certificate is issued by the countries in conjunction with MOSIP.

• Registration - The process of applying for a Foundational Id.

• KYC - Know Your Customer. The process of providing consent to perform profile verification and update.

• Auth - The process of verifying one’s identity.

• FPS - Frames Per Second

• Management Server - A server run by the device provider to manage the life cycle of the biometric devices.

• Device Registration - The process of a device obtaining a certificate from the management server.

• Signature - All signatures should be as per RFC 7515.

• header in signature - The header in the signature means the attribute with "alg" set to RS256 and x5c set to base64encoded certificate.

• payload is the byte array of the actual data, always represented as base64urlencoded.

• signature - base64urlencoded signature bytes

• ISO format timestamp | ISO 8601 with the format yyyy-mm-ddTHH:MM:ssZ (Example: 2020-12-08T09:39:37Z). This value should be in UTC (Coordinated Universal Time).

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Device Specification

The MOSIP device specification provides compliance guidelines devices for that to work with MOSIP. The compliance is based on device capability, trust and communication protocols. A MOSIP-compliant device would follow the standards established in this document. It is expected that the devices are compliant with this specification and tested and validated. The details of each of these are outlined in the subsequent sections.

Device Capability

The MOSIP-compliant device is expected to perform the following,

• Should have the ability to collect one or more biometric

• Should have the ability to sign the captured biometric image or template.

• Should have the ability to protect secret keys

• Should have no mechanism to inject the biometric

Base Specifications for Devices

For details about biometric data specifications please view the page MOSIP Biometric Specification.

We recommend that countries look at ergonomics, accessibility, ease of usage, and common availability of devices while choosing devices for use in registration and authentication scenarios.

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Device Trust

MOSIP-compliant devices provide a trusted environment for the devices to be used in registration, KYC and AUTH scenarios. The trust level is established based on the device support for trusted execution.

• L1 - The trust is provided by a secure chip with a secure execution environment.

• L0 - The trust is provided at the software level. No hardware-related trust exists. This type of compliance is used in controlled environments.

Foundational Trust Module (FTM)

The foundational trust module would be created using a secure microprocessor capable of performing all required biometric processing and secure storage of keys. The foundational device trust would satisfy the below requirements.

• The module can securely generate, store and process cryptographic keys.

• Generation of asymmetric keys and symmetric keys with TRNG.

• The module can protect keys from extraction.

• The module has to protect the keys from physical tampering, temperature, frequency and voltage-related attacks.

• The module could withstand Hardware cloning.

• The module could withstand probing attacks

• The module provides memory segregation for cryptographic operations and protection against buffer overflow attacks

• The module provides the ability to withstand cryptographic side-channel attacks like Differential Power analysis attacks, Timing attacks.

• CAVP validated the implementation of the cryptographic algorithm.

• The module can perform a cryptographically validatable secure boot.

• The module can run trusted applications.

The foundational device trust derived from this module is used to enable trust-based computing for biometric capture. The foundational device trust module provides a trusted execution environment based on the following:

• Secure Boot

  • Ability to cryptographically verify code before execution.

  • Ability to check for integrity violations of the module/device.

  • Halt upon failure.

  • Ability to securely upgrade and perform forward-only upgrades, to thwart downgrade attacks.

  • SHA256 hash equivalent or above should be used for all hashing requirements

  • All root of trust is provisioned upon first boot or before.

  • All upgrades would be considered a success only after the successful boot with proper hash and signature verification.

  • The boot should fail upon hash/signature failures and would never operate in an intermediary state.

  • A maximum of 10 failed attempts should lock the upgrade process and brick the device. However, chip manufacturers can decide to be less than 10.

• Secure application

  • Ability to run applications that are trusted.

  • Protect against the downgrading of applications.

  • Isolated memory to support cryptographic operations.

  • All trust is anchored during the first boot and not modifiable.

Certification

The FTM should have at least one of the following certifications in each category to meet the given requirement.

Category: Cryptographic Algorithm Implementation

• CAVP (RSA, AES, SHA256, TRNG (DRBGVS), ECC)

{% hint style="info" %} The supported algorithm and curves are listed here {% endhint %}

Category: FTM Chip

(ONE of the following certifications)

• FIPS 140-2 L3 or above

• PCI PTS 5 or above (Pre-certified)

• PCI - PED 2.0 or above (Pre-Certified)

• One of the following Common Criteria (CC) certification

  • https://www.commoncriteriaportal.org/files/ppfiles/pp0035a.pdf

  • https://www.commoncriteriaportal.org/files/ppfiles/pp0084a_pdf.pdf

System/Device Level Tamper (optional)

System/Device Level Tamper Responsiveness is recommended (not mandatory). In this case, FTM should be capable of showcasing Tamper Responsiveness (keys must be erased) against a tamper at the system/device level.

Threats to Protect

The FTM should protect against the following threats.

• Hardware cloning attacks - Ability to protect against attacks that could result in a duplicate with keys.

• Hardware Tamper attacks

  • Physical tamper - No way to physically tamper and obtain its secrets.

  • Voltage & frequency related attacks - Should shield against voltage leaks and should prevent low voltage. The FTM should always be in either the state operational normally or inoperable. The FTM should never be operable when its input voltages are not met.

  • Temperature attacks on the crypto block - Low or High the FTM are expected to operate or reach an inoperable state. No state in between.

• Differential Power Analysis attack.

• Probing attacks - FTM should protect its surface area against any probe-related attacks.

• Segregation of memory for execution of cryptographic operation (crypto block should be protected from buffer overflow type attacks).

• Vulnerability of the cryptographic algorithm implementation.

• Attacks against secure boot & secure upgrade.

• TEE/Secure processor OS attack (if applicable).

Foundational Trust Module Identity

Upon FTM provider approval by the MOSIP adopters, the FTM provider would submit a self-signed public certificate to the adopter. Let us call this the FTM root. The adopter would use this certificate to seed their device's trust database. The FTM root and their key pairs should be generated and stored in FIPS 140-2 Level 3 or more compliant devices with no possible mechanism to extract the keys. The foundational module upon its first boot is expected to generate a random asymmetric key pair and provide the public part of the key to obtain a valid certificate. The FTM provider would validate to ensure that the chip is unique and would issue a certificate with the issuer set to an FTM certificate chain. The entire certificate issuance would be in a secured provisioning facility. Auditable upon notice by the adopters or its approved auditors. The certificate issued to the module will have a defined validity period as per the MOSIP certificate policy document defined by the MOSIP adopters. This certificate and private key within the FTM chip is expected to be in its permanent memory.

{% hint style="info" %} The validity of the chip certificate can not exceed 20 years from the date of manufacturing. {% endhint %}

Device

MOSIP devices are most often used to collect biometrics. The devices are expected to follow the specification for all levels of compliance and their usage. The MOSIP devices fall under the category of Trust Level 3 (TL3) as defined in MOSIP architecture. At TL3 device is expected to be whitelisted with a fully capable PKI and secure storage of keys at the hardware.

• L0 - A device can obtain L0 certification when it uses a software-level cryptographic library with no secure boot or FTM. These devices will follow different device identities and the same would be mentioned as part of exception flows.

• L1 - A device can obtain L1 certification when it is built in a secure facility with one of the certified FTM.

Device Identity

All devices that connect to MOSIP must be identifiable. MOSIP believes in cryptographic Identity as its basis for trust.

Physical ID

An identification mark that shows MOSIP compliance and a readable unique device serial number (minimum of 12 alphanumeric characters) make and model. The same information has to be available over a 2D QR Code or Barcode. This is to help field support and validation.

Digital ID

A digital device ID in MOSIP would be a signed JSON (RFC 7515) as follows:

{
  "serialNo": "Serial number",
  "make": "Make of the device",
  "model": "Model of the device",
  "type": "Type of the biometric device",
  "deviceSubType": "Subtypes of the biometric device",
  "deviceProvider": "Device provider name",
  "deviceProviderId": "Device provider id",
  "dateTime": "Current datetime in ISO format"
}

Signed with the JSON Web Signature (RFC 7515) using the "Foundational Trust Module" Identity key, this data is the fundamental identity of the device. Every MOSIP-compliant device will need the foundational trust module.

The only exception to this rule is for the L0-compliant devices that have the purpose of "Registration". L0 devices would sign the Digital Id with the device key.

A signed digital ID would look as follows:

"digitalId": "base64urlencoded(header).base64urlencoded(payload).base64urlencoded(signature)"

The header in the digital id would have:

"alg": "RS256",
"typ": "JWT",
"x5c": "<Certificate of the FTM chip, If in case the chain of certificates are sent then the same will be ignored">

MOSIP assumes that the first certificate in the x5c is the FTM's chip public certificate issued by the FTM root certificate.

An unsigned digital ID would look as follows:

"digitalId": "base64urlencoded(payload)"

Payload is the Digital ID JSON object.

{% hint style="info" %} For an L0 unregistered device, the digital id will be unsigned. In all other scenarios, except for a discovery call, the digital ID will be signed either by the chip key (L1) or the device key (L0). {% endhint %}

Accepted Values for Digital ID

Parameters	Description
serialNo	Serial number of the device. This value should be same as printed on the device (Refer Physical ID).
make	Brand name. This value should be the same as printed on the device (Refer to Physical ID).
model	Model of the device. This value should be the same as printed on the device (Refer to Physical ID).
type	Currently allowed values for device type are "Finger", "Iris" or "Face". More types can be added based on Adopter's implementation.
deviceSubType	The device subtype is based on the device type. For Finger - "Slap", "Single" or "Touchless" For Iris - "Single" or "Double" For Face - "Full face"
deviceProvider	Name of the device provider. The device provider should be a legal entity in the country.
dateTime	The current time during the issuance of the request. This is in ISO format.

Keys

List of keys used in the device and their explanation.

• Device Key

Each biometric device would contain an authorized private key after the device registration. This key is rotated frequently based on the requirement of the respective adopter of MOSIP. By default, MOSIP recommends a 30-day key rotation policy for the device key. The device keys are created by the device providers inside the FTM during a successful registration. The device keys are used for signing the biometric. More details of the signing and its usage will be here. This key is issued by the device provider and the certificate of the device key is issued by the device provider key which in turn is issued by the MOSIP adopter after approval of the device provider's specific model.

• FTM Key

The FTM key is the root of the identity. This key is created by the FTM provider during the manufacturing/provisioning stage. This is a permanent key and would never be rotated. This key is used to sign the Digital ID.

• MOSIP Key

The MOSIP key is the public key provided by the MOSIP adopter. This key is used to encrypt the biometric. Details of the encryption are listed below. We recommend rotating this key every 1 year.

Device Service - Communication Interfaces

The section explains the necessary details of the biometric device connectivity, accessibility, discover-ability and protocols used to build and communicate with the device.

The device should implement only the following set of APIs. All the APIs are independent of the physical layer and the operating system, with the invocation being different across operating systems. While the operating system names are defined in this spec a similar technology can be used for unspecified operating systems. It is expected that the device service ensures that the device is connected locally to the host.

Device Discovery

Device discovery would be used to identify MOSIP-compliant devices in a system by the applications. The protocol is designed as a simple plug-and-play with all the necessary abstractions to the specifics.

Device Discovery Request

{
  "type": "type of the device"
}

Accepted Values for Device Discovery Request

• type - "Biometric Device", "Finger", "Face", "Iris"

{% hint style="info" %} "Biometric Device" - is a special type and is used in case you are looking for any biometric device. {% endhint %}

Device Discovery Response

[
  {
    "deviceId": "Internal ID",
    "deviceStatus": "Device status",
    "certification": "Certification level",
    "serviceVersion": "Device service version",
    "deviceSubId": ["Array of supported device sub Ids"],
    "callbackId": "Base URL to reach the device",
    "digitalId": "Unsigned Digital ID of the device",
    "deviceCode": "Same as serialNo in digital ID",
    "specVersion": ["Array of supported MDS specification version"],
    "purpose": "Auth or Registration or empty if not registered",
    "error": {
      "errorCode": "101",
      "errorInfo": "Invalid JSON Value Type For Discovery.."
    }
  },
  ...
]

Accepted Values for Device Discovery Response

Parameters	Description
deviceStatus	Allowed values are "Ready", "Busy", "Not Ready" or "Not Registered". Error codes should be sent for device in "Busy", "Not Ready" and "Not Registered" from the below error code section.
certification	Allowed values are "L0" or "L1" based on the level of certification.
serviceVersion	Device service version.
deviceId	Internal ID to identify the actual biometric device within the device service.
deviceSubId	Allowed values are 1, 2 or 3. The device sub-id could be used to enable a specific module in the scanner appropriate for a biometric capture requirement. Device sub id is a simple index which always starts with 1 and increases sequentially for each sub-device present. In the case of Finger/Iris, it's 1 for left slap/iris, 2 for right slap/iris and 3 for two thumbs/irises. The device sub id should be set to 0 if we don't know any specific device sub id (0 is not applicable for fingerprint slap).
callbackId	This differs as per the OS. In the case of Linux and windows operating systems, it is an HTTP URL. In the case of android, it is the intent name. In IOS, it is the URL scheme. The call-back URL takes precedence over future requests as a base URL.
digitalId	Digital ID as per the Digital ID definition but it will not be signed.
deviceCode	Same as serialNo in digital ID.
specVersion	An array of supported MDS specification versions. The array element zero will always contain the spec version using which the response is created.
purpose	Purpose of the device in the MOSIP ecosystem. Allowed values are "Auth" or "Registration".
error	Relevant errors as defined under the error section of this document.
error.errorCode	A standardized error code is defined in the error code section.
error.errorInfo	Description of the error that can be displayed to the end user. Multi-lingual support.

{% hint style="info" %}

• The response is an array that we could have a single device enumerating with multiple biometric options.

• The service should ensure to respond only if the type parameter matches the type of device or the type parameter is a "Biometric Device".

• This response is a direct JSON as shown in the response. {% endhint %}

Windows/Linux

All the device API will be based on the HTTP specification. The device always binds to any of the available ports ranging from 4501 - 4600. The IP address used for binding has to be 127.0.0.1 and not localhost.

The applications that require access to MOSIP devices could discover them by sending the HTTP request to the supported port range. We will call this port the device_service_port in the rest of the document.

HTTP Request:

MOSIPDISC http://127.0.0.1:<device_service_port>/device
HOST: 127.0.0.1: <device_service_port>
EXT: <app name>

HTTP Response:

HTTP/1.1 200 OK
CACHE-CONTROL:no-store
LOCATION:http://127.0.0.1:<device_service_port>
Content-Length: length in bytes of the body
Content-Type: application/json
Connection: Closed

{% hint style="info" %}

• The payloads are JSON in both cases and are part of the body.

• CallbackId would be set to the http://127.0.0.1:<device_service_port>/. So, the caller will use the respective HTTP verb/method and the URL to call the service. {% endhint %}

Android

For details on android specifications please view the section - Android SBI Specification.

Device Info

The device information API would be used to identify the MOSIP-compliant devices and their status by the applications.

Device Info Request

NA

Accepted Values for Device Info Request

NA

Device Info Response

[
  {
    "deviceInfo": {
      "deviceStatus": "Current status",
      "deviceId": "Internal ID",
      "firmware": "Firmware version",
      "certification": "Certification level",
      "serviceVersion": "Device service version",
      "deviceSubId": ["Array of supported device sub Ids"],
      "callbackId": "Baseurl to reach the device",
      "digitalId": "Signed digital id as described in the digital id section of this document.",
      "deviceCode": "Same as serialNo in digital ID",
      "env": "Target environment",
      "purpose": "Auth or Registration",
      "specVersion": ["Array of supported MDS specification version"],
    },
    "error": {
      "errorCode": "101",
      "errorInfo": "Invalid JSON Value "
    }
  }
  ...
]

So the API would respond in the following format.

[
  {
    "deviceInfo": "base64urlencode(header).base64urlencode(payload).base64urlencode(signature)"
    "error": {
      "errorCode": "100",
      "errorInfo": "Device not registered. In this case, the device info will be only base64urlencode(payload)"
    }
  }
]

Allowed values for Device Info Response

Parameters	Description
deviceInfo	The deviceInfo object is sent as JSON Web Token (JWT). For a device which is not registered, the deviceInfo will be unsigned. For a device which is registered, the deviceInfo will be signed using the device key.
deviceInfo.deviceStatus	This is the status of the device. Allowed values are "Ready", "Busy", "Not Ready" or "Not Registered". Error codes should be sent for device in "Busy", "Not Ready" and "Not Registered" from the below error code section.
deviceInfo.deviceId	Internal Id to identify the actual biometric device within the device service.
deviceInfo.firmware	The exact version of the firmware. In the case of L0, this is the same as serviceVersion.
deviceInfo.certification	Allowed values are "L0" or "L1" based on the level of certification.
deviceInfo.serviceVersion	The version of the MDS specification that is supported.
deviceInfo.deviceId	Internal ID to identify the actual biometric device within the device service.
deviceSubId	Allowed values are 1, 2 or 3. The device sub-id could be used to enable a specific module in the scanner appropriate for a biometric capture requirement. Device sub id is a simple index which always starts with 1 and increases sequentially for each sub-device present. In the case of Finger/Iris, it's 1 for left slap/iris, 2 for right slap/iris and 3 for two thumbs/irises. The device sub id should be set to 0 if we don't know any specific device sub id (0 is not applicable for fingerprint slap).
deviceInfo.callbackId	This differs as per the OS. In the case of Linux and windows operating systems, it is an HTTP URL. In the case of android, it is the intent name. In IOS, it is the URL scheme. The call-back URL takes precedence over future requests as a base URL.
deviceInfo.digitalId	The digital id is as per the digital id definition. For L0 devices which is not registered, the digital id will be unsigned. For L0 devices which are registered, the digital id will be signed using the device key. For L1 devices, the digital id will be signed using the FTM key.
deviceInfo.env	The target environment. For devices that are not registered the environment is "None". For a device that is registered, then send the environment in which it is registered. Allowed values are "Staging", "Developer", "Pre-Production" or "Production".
deviceInfo.purpose	The purpose of the device in the MOSIP ecosystem. For devices that are not registered the purpose is empty. Allowed values are "Auth" or "Registration".
deviceInfo.specVersion	An array of supported MDS specification versions. The array element Zero will always contain the spec version using which the response is created.
error	Relevant errors as defined under the error section of this document.
error.errorCode	A standardized error code is defined in the error code section.
error.errorInfo	Description of the error that can be displayed to the end user. Multi-lingual support.

{% hint style="info" %}

• The response is an array that we could have a single device enumerating with multiple biometric options.

• The service should ensure to respond only if the type parameter matches the type of device or the type parameter is a "Biometric Device". {% endhint %}

Windows/Linux

The applications that require more details of the MOSIP devices could get them by sending the HTTP request to the supported port range. The device always binds to any of the available ports ranging from 4501 - 4600. The IP address used for binding has to be 127.0.0.1 and not localhost.

HTTP Request:

MOSIPDINFO http://127.0.0.1:<device_service_port>/info
HOST: 127.0.0.1:<device_service_port>
EXT: <app name>

HTTP Response:

HTTP/1.1 200 OK
CACHE-CONTROL:no-store
LOCATION:http://127.0.0.1:<device_service_port>
Content-Length: length in bytes of the body
Content-Type: application/json
Connection: Closed

{% hint style="info" %} The payloads are JSON in both cases and are part of the body. {% endhint %}

Android

For details on android specifications please view the section - Android SBI Specification.

Capture

The capture request would be used to capture a biometric from MOSIP-compliant devices by the applications. The captured call will respond with success to only one call at a time. So, in case of a parallel call, the device info details are sent with the status "Busy".

Capture Request

{
  "env": "Target environment",
  "purpose": "Auth or Registration",
  "specVersion": "Expected version of the MDS spec",
  "timeout": "Timeout for capture",
  "captureTime": "Capture request time in ISO format",
  "domainUri": "URI of the auth server",
  "transactionId": "Transaction Id for the current capture",
  "bio": [
    {
      "type": "Type of the biometric data",
      "count":  "Finger/Iris count, in case of face max, is set to 1",
      "bioSubType": ["Array of subtypes"],
      "requestedScore": "Expected quality score that should match to complete a successful capture",
      "deviceId": "Internal Id",
      "deviceSubId": "Specific Device Sub Id",
      "previousHash": "Hash of the previous block"
    }
  ],
  "customOpts": {
    //Max of 50 key-value pairs. This is so that vendor-specific parameters can be sent if necessary. The values cannot be hardcoded and have to be configured by the apps server and should be modifiable upon need by the applications. Vendors are free to include additional parameters and fine-tuning parameters. None of these values should go undocumented by the vendor. No sensitive data should be available in the customOpts.
  }
}

{% hint style="info" %} The count value should be driven by the count of the bioSubType for Iris and Finger. For Face, there will be no bioSubType but the count should be "1". {% endhint %}

Allowed Values for Capture Request

Parameters	Description
env	The target environment. Allowed values are "Staging", "Developer", "Pre-Production" or "Production".
purpose	The purpose of the device in the MOSIP ecosystem. For devices that are not registered the purpose is empty. Allowed values are "Auth" or "Registration".
specVersion	Expected version of MDS specification.
timeout	Max time the app will wait for the capture. It's expected that the API will respond back before the timeout with the best frame. All timeouts are in milliseconds.
captureTime	Time of capture in ISO format. The time is as per the requested application.
domainUri	URI of the authentication server. This can be used to federate across multiple providers or countries or unions.
transactionId	Unique Id of the transaction. This is an internal Id to the application that's requesting a capture. Different IDs should be used for every request. The transactionId can have minimum lenght as 4 and max length as 50. Allowed characters in transactionId are alphabets, numbers and hyphens (-). If the above validations are not met then a error can be thrown in the error code section.
bio.type	Allowed values are "Finger", "Iris" or "Face".
bio.count	The number of biometric data that is collected for a given type. The device should validate and ensure that this number is in line with the type of biometric that's captured.
bio.bioSubType	For Finger: ["Left IndexFinger", "Left MiddleFinger", "Left RingFinger", "Left LittleFinger", "Left Thumb", "Right IndexFinger", "Right MiddleFinger", "Right RingFinger", "Right LittleFinger", "Right Thumb", "UNKNOWN"] For Iris: ["Left", "Right", "UNKNOWN"] For Face: No bioSubType
bio.requestedScore	Upon reaching the quality score the biometric device is expected to auto-capture the image. If the requested score is not met, until the timeout, the best frame during the capture sequence must be captured/returned. This value will be scaled from 0 - 100 for NFIQ v1.0. The logic for scaling is mentioned below.
bio.deviceId	Internal Id to identify the actual biometric device within the device service.
bio.deviceSubId	Allowed values are 1, 2 or 3. The device sub-id could be used to enable a specific model of the scanner appropriate for a biometric capture requirement. Device sub id is a simple index that always starts with 1 and increases sequentially for each sub-device present. In the case of Finger/Iris, it's 1 for left slap/iris, 2 for right slap/iris and 3 for two thumbs/irises. The device sub id should be set to 0 if we don't know any specific device sub id (0 is not applicable for fingerprint slap).
bio.previousHash	For the first capture, the previousHash is the SHA256 hash of an empty UTF-8 string. From the second capture the previous capture's "hash" is used as input. This is used to chain all the captures across modalities so all captures have happened for the same transaction and during the same time.
customOpts	In case, the device vendor wants to send additional parameters they can use this to send key-value pairs if necessary. The values cannot be hard coded and have to be configured by the app's server and should be modifiable upon need by the applications. Vendors are free to include additional parameters and fine-tune the process. None of these values should go undocumented by the vendor. No sensitive data should be available in the customOpts.

NFIQ v1.0 on a scale of 0-100 (quality score).

Scale	NFIQ v1.0
81 - 100	1
61 - 80	2
41 - 60	3
21 - 40	4
0 - 20	5

Capture Response

{
  "biometrics": [
    {
      "specVersion": "MDS spec version",
      "data": {
        "digitalId": "digital Id as described in this document",
        "deviceCode": "Same as serialNo in digital ID",
        "deviceServiceVersion": "MDS version",
        "bioType": "Finger",
        "bioSubType": "UNKNOWN",
        "purpose": "Auth or Registration",
        "env": "Target environment",
        "domainUri": "URI of the auth server",
        "bioValue": "Encrypt biodata (ISO) with random 256-bit AES key (session key) and encode encrypted biodata with base64 URL safe encoding.",
        "transactionId": "Unique transaction id",
        "timestamp": "Capture datetime in ISO format",
        "requestedScore": "Floating point number to represent the minimum required score for the capture",
        "qualityScore": "Floating point number representing the score for the current capture"
      },
      "hash": "sha256 in hex format in upper case (previous "hash" + sha256 hash of the current biometric ISO data before encryption)",
      "sessionKey": "Encrypt the session key (used to encrypt the bioValue) with MOSIP public key and encode encrypted session key with base64 URL safe encoding.",
      "thumbprint": "SHA256 representation of the certificate (HEX encoded) that was used for encryption of session key. All texts to be treated as uppercase without any spaces or hyphens.",
      "error": {
        "errorCode": "101",
        "errorInfo": "Invalid JSON Value"
      }
    },
    {
      "specVersion": "MDS spec version",
      "data": {
        "digitalId": "Digital Id as described in this document",
        "deviceCode": "Same as serialNo in digital ID",
        "deviceServiceVersion": "MDS version",
        "bioType": "Finger",
        "bioSubType": "Left IndexFinger",
        "purpose": "Auth or Registration",
        "env": "target environment",
        "domainUri": "URI of the auth server",
        "bioValue": "Encrypt biodata (ISO) with random 256-bit AES key (session key) and encode encrypted biodata with base64 URL safe encoding.",
        "transactionId": "unique transaction id",
        "timestamp": "Capture datetime in ISO format",
        "requestedScore": "Floating point number to represent the minimum required score for the capture",
        "qualityScore": "Floating point number representing the score for the current capture"
      },
      "hash": "sha256 in hex format in upper case (previous "hash" + sha256 hash of the current biometric ISO data before encryption)",
      "sessionKey": "Encrypt the session key (used to encrypt the biovalue) with MOSIP public key and encode encrypted session key with base64 URL safe encoding.",
      "thumbprint": "SHA256 representation of the certificate (HEX encoded) that was used for encryption of session key. All texts to be treated as uppercase without any spaces or hyphens.",
      "error": {
        "errorCode": "101",
        "errorInfo": "Invalid JSON Value"
      }
    }
  ]
}

Accepted Values for Capture Response

Parameters	Description
specVersion	The version of the MDS specification using which the response was generated.
data	The data object is sent as JSON Web Token (JWT). The data block will be signed using the device key.
data.digitalId	The digital id is as per the digital id definition in JWT format. For L0 devices, the digital id will be signed using the device key. For L1 devices, the digital id will be signed using the FTM key.
data.deviceCode	Same as serialNo in digital ID.
data.deviceServiceVersion	MDS version
data.bioType	Allowed values are "Finger", "Iris" or "Face".
data.bioSubType	For Finger: ["Left IndexFinger", "Left MiddleFinger", "Left RingFinger", "Left LittleFinger", "Left Thumb", "Right IndexFinger", "Right MiddleFinger", "Right RingFinger", "Right LittleFinger", "Right Thumb", "UNKNOWN"] For Iris: ["Left", "Right", "UNKNOWN"] For Face: No bioSubType
data.purpose	The purpose of the device in the MOSIP ecosystem. Allowed values are "Auth".
data.env	The target environment. Allowed values are "Staging", "Developer", "Pre-Production" or "Production".
data.domainUri	URI of the authentication server. This can be used to federate across multiple providers or countries or unions.
data.bioValue	Biometric data is encrypted with a random symmetric (AES GCM) key and base-64-URL encoded. For symmetric key encryption of bioValue, (biometrics.data.timestamp XOR transactoinId) is computed and the last 16 bytes and the last 12 bytes of the results are set as the aad and the IV(salt) respectively. Look at the Authentication document to understand more about encryption.
data.transactionId	Same transactionId shared in the request should be used.
data.timestamp	Time as per the biometric device. Note: The biometric device is expected to sync its time from the management server at regular intervals so accurate time could be maintained on the device.
data.requestedScore	Floating point number to represent the minimum required score for the capture. This value will be scaled from 0 - 100 for NFIQ v1.0. The logic for scaling is mentioned above.
data.qualityScore	The floating point number represents the score for the current capture. This value will be scaled from 0 - 100 for NFIQ v1.0. The logic for scaling is mentioned above.
hash	sha256 in hex format in upper case (previous "hash" + sha256 hash of the current biometric ISO data before encryption)
sessionKey	The session key (used for the encryption of the biodata (ISO)) is encrypted using the MOSIP public certificate with RSA/ECB/OAEPWITHSHA-256ANDMGF1PADDING algorithm and then encode the encrypted session key with base64 URL safe encoding.
thumbprint	SHA256 representation of the certificate (HEX encoded) that was used for encryption of the session key. All texts are to be treated as uppercase without any spaces or hyphens.
error	Relevant errors as defined under the error section of this document.
error.errorCode	Standardized error code defined in the error code section.
error.errorInfo	Description of the error that can be displayed to the end-user. Multi-lingual support.

The entire data object is sent in JWT format. So, the data object will look like this:

"data" : "base64urlencode(header).base64urlencode(payload).base64urlencode(signature)
payload - is defined as the entire byte array of the data block.

Windows/Linux

The applications that require capturing biometric data from a MOSIP device could do so by sending the HTTP request to the supported port range.

HTTP Request:

CAPTURE [http://127.0.0.1:<device_service_port>/capture](http://127.0.0.1/capture)
HOST: 127.0.0.1: <apps port>
EXT: <app name>

HTTP Response:

HTTP/1.1 200 OK
CACHE-CONTROL:no-store
LOCATION:[http://127.0.0.1](http://127.0.0.1):<device_service_port>
Content-Length: length in bytes of the body
Content-Type: application/json
Connection: Closed

{% hint style="info" %} The payloads are JSON in both cases and are part of the body. {% endhint %}

Android

For details on android specifications please view the section - Android SBI Specification.

Device Stream

The device would open a stream channel to send live video streams. This would help when there is an assisted operation to collect biometrics. Please note the stream APIs are available only for the registration environment.

Used only for registration module-compatible devices. This API is visible only for the devices that are registered for the purpose of "Registration".

Device Stream Request

{
  "deviceId": "Internal Id",
  "deviceSubId": "Specific device sub Id",
  "timeout": "Timeout for stream"
}

Allowed Values for device Stream Request

Parameters	Description
deviceId	Internal Id to identify the actual biometric device within the device service.
deviceSubId	Allowed values are 1, 2 or 3. The device sub-id could be used to enable a specific module in the scanner appropriate for a biometric capture requirement. Device sub id is a simple index which always starts with 1 and increases sequentially for each sub-device present. In the case of Finger/Iris, it's 1 for left slap/iris, 2 for right slap/iris and 3 for two thumbs/irises. The device sub id should be set to 0 if we don't know any specific device sub id (0 is not applicable for fingerprint slap).
timeout	Max time after which the stream should close. This is an optional parameter and by default, the value will be 5 minutes. All timeouts are in milliseconds.

Device Stream Response

Live Video stream with a quality of 3 frames per second or more using M-JPEG.

{% hint style="info" %} The preview should have quality markings and segment markings. The preview would also be used to display an error message on the user screen. All error messages should be localized. {% endhint %}

Error Response for Device Stream

{
  "error": {
    "errorCode": "202",
    "errorInfo": "No Device Connected."
  }
}

Windows/Linux

The applications that require more details of the MOSIP devices could get them by sending the HTTP request to the supported port range.

HTTP Request:

STREAM   http://127.0.0.1:<device_service_port>/stream
HOST: 127.0.0.1: <apps port>
EXT: <app name>

HTTP Response: HTTP Chunk of frames to be displayed. Minimum frames 3 per second.

Android

For details on android specifications please view the section - Android SBI Specification.

Registration Capture

The registration client application will discover the device. Once the device is discovered the status of the device is obtained with the device info API. During the registration, the registration client sends the RCAPTURE API and the response will provide the actual biometric data in a digitally signed non-encrypted form. When the Device Registration Capture API is called the frames should not be added to the stream. The device is expected to send the images in ISO format.

The requestedScore is on a scale of 1-100 (NFIQ v2.0 for fingerprints). So, in cases where you have four fingers the average of all will be considered for the capture threshold. The device would always send the best frame during the capture time even if the requested score is not met.

The API is used by devices that are compatible with the registration module. This API should not be supported by devices that are compatible with authentication.

Registration Capture Request

{
  "env":  "Target environment",
  "purpose": "Auth or Registration",
  "specVersion": "Expected MDS spec version",
  "timeout": "Timeout for registration capture",
  "captureTime": "Time of capture request in ISO format",
  "transactionId": "Transaction Id for the current capture",
  "bio": [
    {
      "type": "Type of the biometric data",
      "count":  "Finger/Iris count, in case of face max, is set to 1",
      "bioSubType": ["Array of subtypes"], //Optional
      "exception": ["Finger or Iris to be excluded"],
      "requestedScore": "Expected quality score that should match to complete a successful capture",
      "deviceId": "Internal Id",
      "deviceSubId": "Specific device Id",
      "previousHash": "Hash of the previous block"
    }
  ],
  "customOpts": {
    //max of 50 key-value pairs. This is so that vendor-specific parameters can be sent if necessary. The values cannot be hardcoded and have to be configured by the apps server and should be modifiable upon need by the applications. Vendors are free to include additional parameters and fine-tuning parameters. None of these values should go undocumented by the vendor. No sensitive data should be available in the customOpts.
  }
}

{% hint style="info" %} To capture the exception photo exception value for Iris or Finger should be sent in bio.exception for bio.type = 'Face'. ICAO checks are not mandatory here but one face must be present within the frame. {% endhint %}

Accepted Values for Registration Capture Request

Parameters	Description
env	The target environment. Allowed values are "Staging", "Developer", "Pre-Production" or "Production".
purpose	The purpose of the device in the MOSIP ecosystem. For devices that are not registered the purpose is empty. Allowed values are "Auth" or "Registration".
specVersion	Expected version of MDS specification.
timeout	Max time the app will wait for the capture. Its expected that the API will respond back before timeout with the best frame. All timeouts are in milliseconds.
captureTime	Time of capture in ISO format. The time is as per the requesting application.
transactionId	Unique Id of the transaction. This is an internal Id to the application that's requesting a capture. Different IDs should be used for every request. The transactionId can have minimum lenght as 4 and max length as 50. Allowed characters in transactionId are alphabets, numbers and hyphens (-). If the above validations are not met then a error can be thrown in the error code section.
bio.type	Allowed values are "Finger", "Iris" or "Face".
bio.count	Number of biometric data that is collected for a given type. The device should validate and ensure that this number is in line with the type of biometric that's captured.
bio.bioSubType	Array of bioSubType for respective biometric type. For Finger: ["Left IndexFinger", "Left MiddleFinger", "Left RingFinger", "Left LittleFinger", "Left Thumb", "Right IndexFinger", "Right MiddleFinger", "Right RingFinger", "Right LittleFinger", "Right Thumb", "UNKNOWN"] For Iris: ["Left", "Right", "UNKNOWN"] For Face: No bioSubType This is an optional parameter.
bio.exception	This is an array and all the exceptions are marked. In case exceptions are sent for face then follow the exception photo specification above. For Finger: ["Left IndexFinger", "Left MiddleFinger", "Left RingFinger", "Left LittleFinger", "Left Thumb", "Right IndexFinger", "Right MiddleFinger", "Right RingFinger", "Right LittleFinger", "Right Thumb"] For Iris: ["Left", "Right"]
bio.requestedScore	Upon reaching the quality score the biometric device is expected to auto capture the image.
bio.deviceId	Internal Id to identify the actual biometric device within the device service.
bio.deviceSubId	Allowed values are 1, 2 or 3. The device sub id could be used to enable a specific module in the scanner appropriate for a biometric capture requirement. Device sub id is a simple index that always starts with 1 and increases sequentially for each sub-device present. In case of Finger/Iris its 1 for left slap/iris, 2 for right slap/iris and 3 for two thumbs/irises. The device sub id should be set to 0 if we don't know any specific device sub id (0 is not applicable for fingerprint slap).
bio.previousHash	For the first capture the previousHash is the SHA256 hash of an empty UTF-8 string. From the second capture the previous capture's "hash" is used as input. This is used to chain all the captures across modalities so all captures have happened for the same transaction and during the same time.
customOpts	In case, the device vendor wants to send additional parameters they can use this to send key value pair if necessary. The values cannot be hard coded and have to be configured by the apps server and should be modifiable upon need by the applications. Vendors are free to include additional parameters and fine-tuning the process. None of these values should go undocumented by the vendor. No sensitive data should be available in the customOpts.

Registration Capture Response

{
  "biometrics": [
    {
      "specVersion": "MDS Spec version",
      "data": {
        "digitalId": "Digital id of the device as per the Digital Id definition..",
        "bioType": "Biometric type",
        "deviceCode": "Same as serialNo in digital ID",
        "deviceServiceVersion": "MDS version",
        "bioSubType": "Left IndexFinger",
        "purpose": "Auth or Registration",
        "env": "Target environment",
        "bioValue": "base64urlencoded biometrics (ISO format)",
        "transactionId": "Unique transaction id sent in request",
        "timestamp": "2019-02-15T10:01:57Z",
        "requestedScore": "Floating point number to represent the minimum required score for the capture. This ranges from 0-100.",
        "qualityScore": "Floating point number representing the score for the current capture. This ranges from 0-100."
      },
      "hash": "sha256 in hex format in upper case (previous "hash" + sha256 hash of the current biometric ISO data)",    
      "error": {
        "errorCode": "101",
        "errorInfo": "Invalid JSON Value Type For Discovery.. ex: {type: 'Biometric Device' or 'Finger' or 'Face' or 'Iris' } "
      }
    },
    {
      "specVersion": "MDS Spec version",
      "data": {
        "deviceCode": "Same as serialNo in digital ID",
        "bioType": "Finger",
        "digitalId": "Digital id of the device as per the Digital Id definition.",
        "deviceServiceVersion": "MDS version",
        "bioSubType": "Left MiddleFinger",
        "purpose": "Auth or Registration",
        "env": "Target environment",
        "bioValue": "base64urlencoded extracted biometric (ISO format)",
        "transactionId": "Unique transaction id sent in request",
        "timestamp": "2019-02-15T10:01:57Z",
        "requestedScore": "Floating point number to represent the minimum required score for the capture. This ranges from 0-100",
        "qualityScore": "Floating point number representing the score for the current capture. This ranges from 0-100"
      },
      "hash": "sha256 in hex format in upper case (previous "hash" + sha256 hash of the current biometric ISO data)",
      "error": {
        "errorCode": "101",
        "errorInfo": "Invalid JSON Value Type For Discovery.. ex: {type: 'Biometric Device' or 'Finger' or 'Face' or 'Iris' }"
      }
    }
  ]
}

Allowed Values for Registration Capture Response

Parameters	Description
specVersion	Version of the MDS specification using which the response was generated.
data	The data object is sent as JSON Web Token (JWT). The data block will be signed using the device key.
data.bioType	Allowed values are "Finger", "Iris" or "Face".
data.digitalId	The digital id as per the digital id definition in JWT format. For L0 devices, the digital id will be signed using the device key. For L1 devices, the digital id will be signed using the FTM key.
data.bioSubType	For Finger: ["Left IndexFinger", "Left MiddleFinger", "Left RingFinger", "Left LittleFinger", "Left Thumb", "Right IndexFinger", "Right MiddleFinger", "Right RingFinger", "Right LittleFinger", "Right Thumb", "UNKNOWN"] For Iris: ["Left", "Right", "UNKNOWN"] For Face: No bioSubType
data.deviceServiceVersion	MDS Version
data.env	The target environment. Allowed values are "Staging", "Developer", "Pre-Production" or "Production".
data.purpose	The purpose of the device in the MOSIP ecosystem. Allowed values are "Auth" or "Registration".
data.bioValue	Base64-URL-encoded biometrics (in ISO format)
data.transactionId	Same transactionId shared in the request should be used.
data.timestamp	Time as per the biometric device. Note: The biometric device is expected to sync its time from the management server at regular intervals so accurate time could be maintained on the device.
data.requestedScore	Floating point number to represent the minimum required score for the capture.
data.qualityScore	Floating point number representing the score for the current capture.
hash	sha256 in hex format in upper case (previous "hash" + sha256 hash of the current biometric ISO data).
error	Relevant errors as defined under the error section of this document.
error.errorCode	Standardized error code defined in the error code section.
error.errorInfo	Description of the error that can be displayed to end user. Multi lingual support.

Windows/Linux

The applications that require more details of the MOSIP devices could get them by sending the HTTP request to the supported port range.

HTTP Request:

RCAPTURE  http://127.0.0.1:<device_service_port>/capture
HOST: 127.0.0.1: <apps port>
EXT: <app name>

HTTP Response: HTTP response.

Android

For details on android specifications please view the section - Android SBI Specification.

---

Certificates

The MOSIP server would provide the following retrieve encryption certificate API which is white-listed to the management servers of the device provider or their partners.

Retrieve Encryption Certificate Request URL

POST https://{base_url}/v1/masterdata/device/encryptioncertficates

Version: v1

Retrieve Encryption Certificate Request

{
  "id": "io.mosip.auth.country.certificate",
  "version": "certificate server API version as defined above",
  "request": {
    "data": {
      "env":  "target environment",
      "domainUri": "uri of the auth server"
    }
  },
  "requesttime": "current timestamp in ISO format"
}

The request is sent in a JWT format. So the final request will look like this:

"request": {
  "data": "base64urlencode(header).base64urlencode(payload).base64urlencode(signature)"
}

Accepted Values for Retrieve Certificate Request

env - Allowed values are Staging| Developer| Pre-Production | Production
domainUri - unique uri per auth providers. This can be used to federate across multiple providers or countries or unions.

Encryption Certificate Response

{
  "id": "io.mosip.auth.country.certificate",
  "version": "certificate server API version as defined above",
  "responsetime": "Current time in ISO format",
  "response": [
    {
      "certificate": "base64encoded certificate as x509 V3 format"
    }
  ]
}

The entire response is sent in a JWT format. So the final response will look like this:

"response" : "base64urlencode(header).base64urlencode(payload).base64urlencode(signature)"

---

Management Server and Management Client

Management Server Functionalities and Interactions

The management server has the following objectives.

1. Validate the devices to ensure they genuine devices from the respective device provider. This can be achieved using the device info and the certificates for the Foundational Trust Module.

2. Register the genuine device with the MOSIP device server.

3. Manage/Sync time between the end device and the server. The time to be synced should be the only trusted time accepted by the device.

4. Ability to issue commands to the end device for

   1. De-registration of the device (Device Keys)

   2. Collect device information to maintain, manage, support and upgrade a device remotely.

5. A central repository of all the approved devices from the device provider.

6. Safe storage of keys using HSM FIPS 140-2 Level 3. These keys are used to issue the device certificate upon registration. The Management Server is created and hosted by the device provider outside of MOSIP software. The communication protocols between the MDS and the Management Server can be decided by the respective device provider. Such communication should be restricted to the above-specified interactions only. No transactional information should be sent to this server.

7. Should have the ability to push updates from the server to the client devices.

{% hint style="info" %} As there is no adopter-specific information being exchanged at the management server or the FTM provisioning server, there are no mandates from MOSIP where these are located globally. However, the adopter is recommended to have an audit and contractual mechanisms to validate the compliance of these components at any point in time. {% endhint %}

Management Client

The management client is the interface that connects the device with the respective management server. The communication between the management server and its clients must be designed with scalability, robustness, performance and security. The management server may add many more capabilities than what is described here, But the basic security objectives should be met at all times irrespective of the offerings.

1. For better and more efficient handling of the device at large volumes, we expect the devices to auto-register to the Management Server.

2. All communication to the server and from the server should follow the below properties.

   1. All communication is digitally signed with the approved algorithms

   2. All communication to the server is encrypted using one of the approved public key cryptography (HTTPS – TLS1.2/1.3 is required with one of the approved algorithms.

   3. All request has timestamps attached in ISO format to the milliseconds inside the signature.

   4. All communication back and forth should have the signed digital id as one of the attributes.

3. It's expected that auto-registration has an absolute way to identify and validate the devices.

4. The management client should be able to detect the devices in a plug-and-play model.

5. All key rotations should be triggered from the server.

6. Should have the ability to detect if it's speaking to the right management server.

7. All upgrades should be verifiable and the client should have the ability to verify software upgrades.

8. Should not allow any downgrade of software.

9. Should not expose any API to capture biometrics. The management server should have no ability to trigger a capture request.

10. No logging of biometric data is allowed. (Both in the encrypted and unencrypted format)

---

Compliance

L1 Certified Device / L1 Device - A device certified as capable of performing encryption on the device inside its trusted zone. L0 Certified Device / L0 Device - A device certified as one where the encryption is done on the host inside its device driver or the MOSIP device service.

Secure Provisioning

Secure provisioning applies to both the FTM and the Device providers.

1. The devices and FTM should have a mechanism to protect against fraudulent attempts to create or replicate.

2. The device and FTM trust should be programmed in a secure facility that is certified by the respective MOSIP adopters.

3. The organization should have a mechanism to segregate the FTMs and Devices built for MOSIP using a cryptographically valid and repeatable process.

4. All debug options within the FTM or device should be disabled permanently

5. All key creations need for provisioning should happen automatically using FIPS 140-2 Level 3 or higher devices. No individual or group or organization should have a mechanism to influence this behaviour.

6. Before the devices/FTM leaves the secure provisioning facility all the necessary trust should be established and should not be re-programmable.

{% hint style="info" %}

• As there is no adopter-specific information being exchanged at the management server or the FTM provisioning server, there are no mandates from MOSIP where these are located globally. However, the adopter is recommended to have an audit and contractual mechanisms to validate the compliance of these components at any point in time.* {% endhint %}

Compliance Level

API	Compatible
Device Discovery	L0/L1
Device Info	L0/L1
Capture	L1
Registration Capture	L0/L1

---

Cryptography

Supported algorithms:

Usage	Algorithm	Key Size	Storage
Encryption of biometrics - Session Key	AES	>=256	No storage, Key is created with TRNG/DRBG inside FTM
Encryption session key data outside of FTM	RSA OAEP	>=2048	FTM trusted memory
Encryption session key data outside of FTM	ECC curve 25519	>=256	FTM trusted memory
Biometric Signature	RSA	>=2048	Key never leaves FTM created and destroyed
Biometric Signature	ECC curve 25519	>=256	Key never leaves FTM created and destroyed
Secure Boot	RSA	>=256	FTM trusted memory
Secure Boot	ECC curve 25519	>=256	FTM trusted memory

{% hint style="info" %} No other ECC curves are supported. {% endhint %}

Signature

In all the above APIs, some of the requests and responses are signed with various keys to verify the requester's authenticity. Here we have detailed the key used for signing a particular block in a request or response body of various APIs.

Request/Response	Block	Signature Key
Device Discovery Response	Device Info	NA as it will not be signed
Device Discovery Response	Digital ID	NA as it will not be signed
Device Info Response	Device Info	NA in case of unregistered device Device Key in case of registered device
Device Info Response	Digital ID	For L0 device using device key For L1 device using FTM chip key
Capture Response	Data	Device key is used
Capture Response	Digital ID	FTM chip key is used
Registration Capture Response	Data	Device key is used
Registration Capture Response	Digital ID	For L0 device using device key For L1 device using FTM chip key

Android SBI Specification

This section explains the mechanism for the SBI devices to communicate in the android operating system.

Status

Draft document V 0.9

Approach

Discovery will return the appId of the discovered items. Users will be given a choice to choose one of the discovered SBI app. The selected app responds back to the intent using the default intent callback functionality.

Device Discovery

Request: io.sbi.device action: io.sbi.device data: no change type: application/json Request Schema: No change in the data structure. The serialized request data as byte array is set in the intent extras with the key as “input”. Response Schema: No change in the data structure. The serialized response data (byte array) is set in the intent extras with the key as “response”.

callbackId should be set to the appId, and can not be empty in android.

Device Info

Request: appId.Info action: appId.Info data: no change type: application/json Request Schema: No change in the data structure. The serialized request data as a byte array is set in the intent extras with the key as “input”. Response Schema: No change in the data structure. The serialized response data as a byte array is set in the intent extras with the key as “response”.

deviceInfo: callbackId should be set to the appId, can not be empty in android.

Capture

Request: appId.Capture action: appId.Capture data: no change type: application/json flag: FLAG_GRANT_READ_URI_PERMISSION Request Schema: No change in the data structure. The serialized request data as a byte array is set in the intent extras with the key as “input”. Response Schema: No change in the data structure. The response content is set as content URI “content://authority/path/id” in the intent extras as a string with the key as “response”.

URI must be invalidated right after the read.

rCapture

Request: appId.rCapture action: appId.rCapture data: no change type: application/json flag: FLAG_GRANT_READ_URI_PERMISSION Request Schema: No change in the data structure. The serialized request data as a byte array is set in the intent extras with the key as “input”. Response Schema: No change in the data structure. The response content is set as content URI “content://authority/path/id” in the intent extras as a string with the key as “response”.

The content provider should not support insert, update, delete

Device Stream

On receiving rCapture request MDS must show the stream within its UI in the foreground.

Security

Ensure to set the correct authority in the manifest and set the android:exported as “False”

Android Tab Specs

Android 9 (API Level 28) and above with hardware-backed key store.

Error Codes

Code	Message
0	Success
100	Device not registered
101	Unable to detect a biometric object
102	Technical error during extraction.
103	Device tamper detected
104	Unable to connect to the management server
105	Image orientation error
106	Device not found
107	Device public key expired
108	Domain public key missing
109	Requested number of biometric (Finger/IRIS) not supported
110	Device is not ready
111	Device is Busy
112	Invalid Transaction ID
5xx	Custom errors. The device provider is free to choose his error code and error messages.