phpman > perldoc > Authen::SCRAM::Server(3pm)

NAME
    Authen::SCRAM::Server - RFC 5802 SCRAM Server

VERSION
    version 0.011

SYNOPSIS
        use Authen::SCRAM::Server;
        use Try::Tiny;

        $server = Authen::SCRAM::Server->new(
            credential_cb => \&get_credentials,
        );

        $username = try {
            # get client-first-message

            $server_first = $server->first_msg( $client_first );

            # send to client and get client-final-message

            $server_final = $server->final_msg( $client_final );

            # send to client

            return $server->authorization_id; # returns valid username
        }
        catch {
            die "Authentication failed!"
        };

DESCRIPTION
    This module implements the server-side SCRAM algorithm.

NAME
    Authen::SCRAM::Server - RFC 5802 SCRAM Server

VERSION
    version 0.011

ATTRIBUTES
  credential_cb (required)
    This attribute must contain a code reference that takes a username (as a character string
    normalized by SASLprep) and returns the four user-credential parameters required by SCRAM:
    "salt", "StoredKey", "ServerKey", and "iteration count". The "salt", "StoredKey" and "ServerKey"
    must be provided as octets (i.e. NOT base64 encoded).

    If the username is unknown, it should return an empty list.

        ($salt, $stored_key, $server_key, $iterations) =
            $server->credential_cb->( $username );

    See RFC 5802: SCRAM Algorithm Overview <http://tools.ietf.org/html/rfc5802#section-3> for
    details.

  auth_proxy_cb
    If provided, this attribute must contain a code reference that takes an authentication username
    and a authorization username (both as character strings), and return a true value if the
    authentication username is permitted to act as the authorization username:

        $bool = $server->auth_proxy_cb->(
            $authentication_user, $authorization_user
        );

    It will only be all called if the authentication username has successfully authenticated. Both
    usernames will have been normalized via "SASLprep" with any transport encoding removed before
    being passed to this function.

  digest
    Name of a digest function available via PBKDF2::Tiny. Valid values are SHA-1, SHA-224, SHA-256,
    SHA-384, or SHA-512. Defaults to SHA-1.

  nonce_size
    Size of the client-generated nonce, in bits. Defaults to 192. The server-nonce will be appended,
    so the final nonce size will be substantially larger.

  skip_saslprep
    A boolean that defaults to false. If set to true, usernames and passwords will not be normalized
    through SASLprep. This is a deviation from the RFC5802 spec and is not recommended.

METHODS
  first_msg
        $server_first_msg = $server->first_msg( $client_first_msg );

    This takes the "client-first-message" received from the client and returns the
    "server-first-message" string to be sent to the client to continue a SCRAM session. Calling this
    again will reset the internal state and initiate a new session. This will throw an exception
    should an error occur.

  final_msg
        $server_final_msg = $server->final_msg( $client_final_msg );

    This takes the "client-final-message" received from the client and returns the
    "server-final-message" string containing the verification signature to be sent to the client.

    If an authorization identity was provided by the client, it will confirm that the authenticating
    username is authorized to act as the authorization id using the "auth_proxy_cb" attribute.

    If the client credentials do not match or the authentication name is not authorized to act as
    the authorization name, then an exception will be thrown.

  authorization_id
        $username = $client->authorization_id();

    This takes no arguments and returns the authorization identity resulting from the SCRAM
    exchange. This is the client-supplied authorization identity (if one was provided and validated)
    or else the successfully authenticated identity.

CHARACTER ENCODING CAVEAT
    The SCRAM protocol mandates UTF-8 interchange. However, all methods in this module take and
    return character strings. You must encode to UTF-8 before sending and decode from UTF-8 on
    receiving according to whatever transport mechanism you are using.

    This is done to avoid double encoding/decoding problems if your transport is already doing UTF-8
    encoding or decoding as it constructs outgoing messages or parses incoming messages.

AUTHOR
    David Golden <dagolden AT cpan.org>

COPYRIGHT AND LICENSE
    This software is Copyright (c) 2014 by David Golden.

    This is free software, licensed under:

      The Apache License, Version 2.0, January 2004

AUTHOR
    David Golden <dagolden AT cpan.org>

COPYRIGHT AND LICENSE
    This software is Copyright (c) 2014 by David Golden.

    This is free software, licensed under:

      The Apache License, Version 2.0, January 2004