Koha/opac/svc/auth/googleopenidconnect
Nicholas van Oudtshoorn 9472711921 Bug 10988 - Fix some wording Fix some outdated wording in googleopenidconnect
Signed-off-by: Mark Tompsett <mtompset@hotmail.com>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>

Signed-off-by: Brendan A Gallagher <brendan@bywatersolutions.com>
2016-04-01 19:25:36 +00:00

233 lines
8.4 KiB
Perl
Executable file

#!/usr/bin/perl
# Copyright vanoudt@gmail.com 2014
# Based on persona code from chris@bigballofwax.co.nz 2013
#
# This file is part of Koha.
#
# Koha is free software; you can redistribute it and/or modify it
# under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.
#
# Koha is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Koha; if not, see <http://www.gnu.org/licenses>.
#
#
# Basic OAuth2/OpenID Connect authentication for google goes like this
#
# The first thing that happens when this script is called is
# that one gets redirected to an authentication url from google
#
# If successful, that then redirects back to this script, setting
# a CODE parameter which we use to look up a json authentication
# token. This token includes an encrypted json id_token, which we
# round-trip back to google to decrypt. Finally, we can extract
# the email address from this.
#
use Modern::Perl;
use CGI qw ( -utf8 escape );
use C4::Auth qw{ checkauth get_session get_template_and_user };
use C4::Context;
use C4::Output;
use LWP::UserAgent;
use HTTP::Request::Common qw{ POST };
use JSON;
use MIME::Base64 qw{ decode_base64url };
my $discoveryDocURL =
'https://accounts.google.com/.well-known/openid-configuration';
my $authendpoint = '';
my $tokenendpoint = '';
my $scope = 'openid email profile';
my $host = C4::Context->preference('OPACBaseURL') // q{};
my $restricttodomain = C4::Context->preference('GoogleOpenIDConnectDomain')
// q{};
# protocol is assumed in OPACBaseURL see bug 5010.
my $redirecturl = $host . '/cgi-bin/koha/svc/auth/googleopenidconnect';
my $issuer = 'accounts.google.com';
my $clientid = C4::Context->preference('GoogleOAuth2ClientID');
my $clientsecret = C4::Context->preference('GoogleOAuth2ClientSecret');
my $ua = LWP::UserAgent->new();
my $response = $ua->get($discoveryDocURL);
if ( $response->is_success ) {
my $json = decode_json( $response->decoded_content );
if ( exists( $json->{'authorization_endpoint'} ) ) {
$authendpoint = $json->{'authorization_endpoint'};
}
if ( exists( $json->{'token_endpoint'} ) ) {
$tokenendpoint = $json->{'token_endpoint'};
}
}
my $query = CGI->new;
sub loginfailed {
my $cgi_query = shift;
my $reason = shift;
$cgi_query->delete('code');
$cgi_query->param( 'OpenIDConnectFailed' => $reason );
my ( $template, $borrowernumber, $cookie ) = get_template_and_user(
{
template_name => 'opac-user.tt',
query => $cgi_query,
type => 'opac',
authnotrequired => 0,
}
);
$template->param( 'invalidGoogleOpenIDConnectLogin' => $reason );
$template->param( 'loginprompt' => 1 );
output_html_with_http_headers $cgi_query, $cookie, $template->output;
return;
}
if ( defined $query->param('error') ) {
loginfailed( $query,
'An authentication error occurred. (Error:'
. $query->param('error')
. ')' );
}
elsif ( defined $query->param('code') ) {
my $stateclaim = $query->param('state');
my $session = get_session( $query->cookie('CGISESSID') );
if ( $session->param('google-openid-state') ne $stateclaim ) {
$session->clear( ["google-openid-state"] );
$session->flush();
loginfailed( $query,
'Authentication failed. Your session has an unexpected state.' );
}
$session->clear( ["google-openid-state"] );
$session->flush();
my $code = $query->param('code');
my $ua = LWP::UserAgent->new();
if ( $tokenendpoint eq q{} ) {
loginfailed( $query, 'Unable to discover token endpoint.' );
}
my $request = POST(
$tokenendpoint,
[
code => $code,
client_id => $clientid,
client_secret => $clientsecret,
redirect_uri => $redirecturl,
grant_type => 'authorization_code',
$scope => $scope
]
);
my $response = $ua->request($request)->decoded_content;
my $json = decode_json($response);
if ( exists( $json->{'id_token'} ) ) {
if ( lc( $json->{'token_type'} ) ne 'bearer' ) {
loginfailed( $query,
'Authentication failed. Incorrect token type.' );
}
my $idtoken = $json->{'id_token'};
# Normally we'd have to validate the token - but google says not to worry here (Avoids another library!)
# See https://developers.google.com/identity/protocols/OpenIDConnect#obtainuserinfo for rationale
my @segments = split( '\.', $idtoken );
unless ( scalar(@segments) == 3 ) {
loginfailed( $query,
'Login token broken: either too many or too few segments.' );
}
my ( $header, $claims, $validation ) = @segments;
$claims = decode_base64url($claims);
my $claims_json = decode_json($claims);
if ( ( $claims_json->{'iss'} ne ( 'https://' . $issuer ) )
&& ( $claims_json->{'iss'} ne $issuer ) )
{
loginfailed( $query,
"Authentication failed. Issuer of authentication isn't Google."
);
}
if ( ref( $claims_json->{'aud'} ) eq 'ARRAY' ) {
warn "Audience is an array of size: "
. scalar( @$claims_json->{'aud'} );
if ( scalar( @$claims_json->{'aud'} ) > 1 )
{ # We don't want any other audiences
loginfailed( $query,
"Authentication failed. Unexpected audience provided." );
}
}
if ( ( $claims_json->{'aud'} ne $clientid )
|| ( $claims_json->{'azp'} ne $clientid ) )
{
loginfailed( $query,
"Authentication failed. Unexpected audience." );
}
if ( $claims_json->{'exp'} < time() ) {
loginfailed( $query, 'Sorry, your authentication has timed out.' );
}
if ( exists( $claims_json->{'email'} ) ) {
my $email = $claims_json->{'email'};
if ( ( $restricttodomain ne q{} )
&& ( index( $email, $restricttodomain ) < 0 ) )
{
loginfailed( $query,
'The email you have used is not valid for this library. Email addresses should conclude with '
. $restricttodomain
. ' .' );
}
else {
my ( $userid, $cookie, $session_id ) =
checkauth( $query, 1, {}, 'opac', $email );
if ($userid) { # A user with this email is registered in koha
print $query->redirect(
-uri => '/cgi-bin/koha/opac-user.pl',
-cookie => $cookie
);
}
else {
loginfailed( $query,
'The email address you are trying to use is not associated with a borrower at this library.'
);
}
}
}
else {
loginfailed( $query,
'Unexpectedly, no email seems to be associated with that acccount.'
);
}
}
else {
loginfailed( $query, 'Failed to get proper credentials from Google.' );
}
}
else {
my $session = get_session( $query->cookie('CGISESSID') );
my $openidstate = 'auth_';
$openidstate .= sprintf( "%x", rand 16 ) for 1 .. 32;
$session->param( 'google-openid-state', $openidstate );
$session->flush();
my $prompt = $query->param('reauthenticate') // q{};
if ( $authendpoint eq q{} ) {
loginfailed( $query, 'Unable to discover authorisation endpoint.' );
}
my $authorisationurl =
$authendpoint . '?'
. 'response_type=code&'
. 'redirect_uri='
. escape($redirecturl) . q{&}
. 'client_id='
. escape($clientid) . q{&}
. 'scope='
. escape($scope) . q{&}
. 'state='
. escape($openidstate);
if ( $prompt || ( defined $prompt && length $prompt > 0 ) ) {
$authorisationurl .= '&prompt=' . escape($prompt);
}
print $query->redirect($authorisationurl);
}