Hawk is an HTTP authentication scheme using a message authentication code (MAC) algorithm to provide partial HTTP request cryptographic verification. — hawk README

Through Composer as dflydev/hawk.

The Client has a few required dependencies. It is generally easier to construct a Client by using the ClientBuilder. A Client can be built without setting anything to get sane defaults.

<?php // Simple example $client = Dflydev\Hawk\Client\ClientBuilder::create() ->build()

<?php // A complete example $client = Dflydev\Hawk\Client\ClientBuilder::create() ->setCrypto($crypto) ->setTimeProvider($timeProvider) ->setNonceProvider($nonceProvider) ->setLocaltimeOffset($localtimeOffset) ->build()

In order for a client to be able to sign a request, it needs to know the credentials for the user making the request, the URL, method, and optionally payload and content type of the request.

All available options include:

• payload: The body of the request
• content_type: The content-type for the request
• nonce: If a specific nonce should be used in favor of one being generated automatically by the nonce provider.
• ext: An ext value specific for this request
• app: The app for this request (Oz specific)
• dlg: The delegated-by value for this request (Oz specific)

<?php $request = $client->createRequest( $credentials, 'http://example.com/foo/bar?whatever', 'POST', array( 'payload' => 'hello world!', 'content_type' => 'text/plain', ) ); // Assuming a hypothetical $headers object that can be used to add new headers // to an outbound request, we can add the resulting 'Authorization' header // for this Hawk request by doing: $headers->set( $request->header()->fieldName(), $request->header()->fieldValue() );

The Request represents everything the client needs to know about a request including a header and the artifacts that were used to create the request.

• header(): A Header instance that represents the request
• artifacts(): An Artifacts instance that contains the values that were used in creating the request

The header is required to be able to get the properly formatted Hawk authorization header to send to the server. The artifacts are useful in the case that authentication will be done on the server response.

Hawk provides the ability for the client to authenticate a server response to ensure that the response sent back is from the intended target.

All available options include:

• payload: The body of the response
• content_type: The content-type for the response

<?php // Assuming a hypothetical $headers object that can be used to get headers sent // back as the response of a user agent request, we can get the value for the // 'Server-Authorization' header. $header = $headers->get('Server-Authorization'); // We need to use the original credentials, the original request, the value // for the 'Server-Authorization' header, and optionally the payload and // content type of the response from the server. $authenticatedResponse = $client->authenticate( $credentials, $request, $header, array( 'payload' => '{"message": "good day, sir!"}', 'content_type' => 'application/json', ) );

<?php // Create a set of Hawk credentials $credentials = new Dflydev\Hawk\Credentials\Credentials( 'afe89a3x', // shared key 'sha256', // default: sha256 '12345' // identifier, default: null ); // Create a Hawk client $client = Dflydev\Hawk\Client\ClientBuilder::create() ->build(); // Create a Hawk request based on making a POST request to a specific URL // using a specific user's credentials. Also, we're expecting that we'll // be sending a payload of 'hello world!' with a content-type of 'text/plain'. $request = $client->createRequest( $credentials, 'http://example.com/foo/bar?whatever', 'POST', array( 'payload' => 'hello world!', 'content_type' => 'text/plain', ) ); // Create a really useful fictional user agent. $userAgent = new Fictional\UserAgent; // Ask a really useful fictional user agent to make a request; note that the // request we are making here matches the details that we told the Hawk client // about our request. $response = Fictional\UserAgent::makeRequest( 'POST', 'http://example.com/foo/bar?whatever', array( 'content_type' => 'text/plain', $request->header()->fieldName() => $request->header()->fieldValue(), ), 'hello world!' ); // This part is optional but recommended! At this point if we have a successful // response we could just look at the content and be done with it. However, we // are given the tools to authenticate the response to ensure that the response // we were given came from the server we were expecting to be talking to. $authenticatedResponse = $client->authenticate( $credentials, $request, $response->headers->get('Server-Authorization'), array( 'payload' => $response->getContent(), 'content_type' => $response->headers->get('content-type'), ) ); if (!$authenticatedResponse) { die("The server did a very bad thing..."); } // Huzzah!

Tools for calculation of and comparison of MAC values.

• calculatePayloadHash($payload, $algorithm, $contentType)
• calculateMac($type, CredentialsInterface $credentials, Artifacts $attributes)
• calculateTsMac($ts, CredentialsInterface $credentials)
• fixedTimeComparison($a, $b)
  Used to ensure that the comparing two strings will always take the same amount of time regardless of whether they are the same or not.

A container for all of the pieces of data that may go into the creation of a MAC.

Represents a valid set of credentials.

• key(): Used to calculate the MAC
• algorithm(): The algorithm used to calculate hashes
• id(): An identifier (e.g. username) for whom the key belongs

In some contexts only the key may be known.

A simple implementation of CredentialsInterface.

<?php $credentials = new Dflydev\Hawk\Credentials\Credentials( $key, // shared key $algorithm, // default: sha256 $id // identifier, default: null );

• fieldName(): The name for the header field
• fieldValue(): The value for the header field
• attributes(): The attributes used to build the field value

• create($fieldName, array $attributes = null)
  Creates a Hawk header for a given field name for a set of attributes.

• createFromString($fieldName, $fieldValue, array $requiredKeys = null)
  Creates a Hawk header for a given field name from a Hawk value string. For example, 'Hawk id="foo", mac="1234"' would be an example of a Hawk value string. This is useful for converting a header value coming in off the wire.

  Throws:

  • Dflydev\Hawk\Header\FieldValueParserException
  • Dflydev\Hawk\Header\NotHawkAuthorizationException

• parseFieldValue($fieldValue, array $requiredKeys = null)
  Parses a field value string into an associative array of attributes.

  Throws:

  • Dflydev\Hawk\Header\FieldValueParserException
  • Dflydev\Hawk\Header\NotHawkAuthorizationException

Indicates that a string claims to be a Hawk string but it cannot be completely parsed. This is mostly a sign of a corrupted or malformed header value.

Indicates that the string has nothing to do with Hawk. Currently means that the string does not start with 'Hawk'.

MIT, see LICENSE.

If you have questions or want to help out, join us in #dflydev on irc.freenode.net.