Description

The VerifyCredentials API can be called to verify Device or User's (or Account Owner's) credentials by simply checking the request's signature, to generate a unique token that can be used to identify a device or user or to renew an existing token.

What is a Token?

In Apstrata, all requests must be authenticated. There are four methods for authenticating Apstrata requests:

Default Signature: This is the most secure method of authentication because it requires hashing all content of a request along with the secret of the account or the password of the user or the device and then sending the hash. (read more)
Simple Signature: This is the easiest method of authentication. It requires hashing a few select parameters along with the secret of the account or the password of the user or the device and then sending the hash. It is recommended for testing and for applications that do not have access to all parameters, e.g., files, in a request. (read more)
Token-Based Authentication: This is the recommended method of authentication for applications that make most requests with Apstrata users and devices, as opposed to owners, for use with SSL encrypted connections over HTTP POST. It provides a similar experience to sessions since a Token is generated and renewed over a period of time, without the need to generate a signature for every request. (read more)
Bearer Token Authentication: This authentication allows the users and devices to issue a request using a bearer token in the header. In order to issue a request with a token bearer header, you first need to generate a token for a user or a device. Users and devices make authenticated requests with a bearer token using the Authorization request header field. (read more)

A Token can be used to authenticate a user or a device in place of a signature. This allows the creation of applications that do not need access to the passwords of the users and devices which are required for signature generation. Tokens provide a layer of simplicity, but must obey the following restrictions:

Token-based authentication is enabled for user and device requests only. Owner requests must use signatures.
Token-based authentication is enabled under secure (https) connections only.

A Token can be created or renewed using GenerateToken, RenewToken and VerifyCredentials APIs. It can then be passed as a parameter to requests instead of the signature.

When no longer needed, Token can be deleted and cleared using DeleteToken.

1- Validating credentials: The validation can be requested for devices, users or account owners, to do so; one needs to call the VerifyCredentials API by simply signing the request. It will return a success response if the credentials are valid or an INVALID_SIGNATURE otherwise.

2- Generating a token: Account owners are not allowed to generate tokens for themselves, it has to be a device or user request sent over https. To do so; a device or a user will have to call VerifyCredentials by signing the request and passing the parameter apsdb.action=generate; the token will be returned upon success. Owners can only generate a token for a device or a user by passing their respective identifier in the parameter apsdb.runAs.

The parameters apsdb.tokenExpires and apsdb.tokenLifeTime are not mandatory when generating a token. For both devices and users, if only one of these parameters is passed, the system configuration default value will be set for the second one. If none of these parameters is passed an eternal token will be generated for the device. However, system configuration default values will be set for the user's token expiry and lifetime. (See the table below for more information about the allowed request parameters).

Note: Default and maximum expiry and life time values can always be configured and modified by the account owner.

3- Renewing a token ( this action is deprecated, henceforward you should use the RenewToken API): Token renewal can only be made through https. To do so; a device or a user will have to call VerifyCredentials using token authentication instead of signing the request, passing their identifier as a parameter (apsws.id) and passing the parameter apsdb.action=renew. The token passed to the request will be renewed and the new token will be returned upon success. Account owners are only allowed to renew tokens by passing the parameter apsdb.runAs.

A token will be renewed only if it hasn't expired and it can't be renewed past its life time, in addition whenever a token is renewed and a new token is returned, the old one would still remain valid for 5 seconds. Unlike users, the devices can have eternal tokens. Eternal tokens cannot be renewed.

The parameter apsdb.bindReferrer must be set to true to take the referrer header into account when renewing the token, and a token that is bound to a specific referrer can't be renewed by another referrer (See the table below for more information about the allowed request parameters).

Specific Request Parameters

(Refer to Common Request Parameters)

Name	Description	Required	Default	Possible Values
apsws.id	Should be sent in case of verifying credentials of a device or a user or generating/renewing a device or user token.	No
apsdb.authToken	Should be sent in case of renewing a token for a device or a user. It contains the token that should be renewed.	No
apsdb.action	Should be sent in case of generating or renewing a device or a user token.	No		generate renew
apsdb.tokenExpires	Should be sent in case of generating a token. It contains the relative time in seconds after which the token expires and becomes unusable.	No	1800 seconds (30 minutes)	Relative time in seconds. It should always be less or equal to 86400 seconds (24 hours).
apsdb.tokenLifetime	Should be sent in case of generating a token. It contains the relative time in seconds after which the token cannot be renewed. After that amount of time, a signature will be needed to be able to generate a new token.	No	7200 seconds (2 hours)	Relative time in seconds. It should always be less or equal to 604800 seconds (1 week).
apsdb.bindReferrer	Should be sent in case of generating a user's token . It specifies if the token should be bound to the referrer.	No	true	true false
apsdb.tokenInCookie	Should be sent in case of generating a user's token. It specifies if the token should be returned in a cookie in the response header.	No	false	true false

Specific Response Elements

(Refer to Common Response Elements)

The following specific "result" element is a child of the common root element "response" and a sibling of the common "metadata" element. It will be returned only in the case where a device or user has asked to generate or renew a token.

Note: If the apsdb.tokenInCookie request parameter is true, then the token will be returned as cookie in the response header. This applies only for users' tokens; Devices' token cannot be bound to a referrer nor set in cookies

Specific Logical Errors

(Refer to Common Logical Error Codes)

Error	Message	Status Code
INVALID_PARAMETER	The parameter [paramName] is not allowed in VerifyCredentials Account has enforced binding to referrer when generating tokens The parameter [paramReferrerName] can only be [true] or [false] Invalid parameter apsdb.runAs	400
INVALID_REQUEST	VerifyCredentials must not be called anonymously Token-based authentication is not allowed for account owners Token Generation is not allowed over non-secure connections. Token-based authentication with cookies requires a referrer to be set A token must be sent in order to renew VerifyCredentials is not allowed over non-secure connections.	400
INVALID_ACTION	An action can only be [generate] or [renew]	400
INVALID_PARAMETER_VALUE	The parameter [apsdb.tokenExpires: xxx] must be equal to or less than [apsdb.tokenLifetime: xxx] The parameter [apsdb.tokenExpires] is not a valid number. The parameter [apsdb.tokenLifetime] is not a valid number. The parameter [apsdb.tokenExpires] can't be a zero or a negative number. The parameter [apsdb.tokenLifetime] can't be a zero or a negative number. The parameter [apsdb.Lifetime] must be equal to or less than [xxx] The parameter [apsdb.tokenExpires] must be equal to or less than [xxx] Eternal tokens can't be renewed.	400
INVALID_TOKEN	Could not find the token [token]	400
INTERNAL_ERROR		500
INVALID_SIGNATURE		400
INVALID_IDENTIFIER		400
MALFORMED_REFERER	Invalid originating referrer from the Referer header [RefererHeaderString]	400
TOO_MANY_TOKENS	The total number of tokens must not exceed [tokenLimit]	400

Examples

Sample Request to generate a token

POST parameters:

Sample Response

Success XML:

Failure XML:

Sample JSON Response