Commit | Line | Data |
85990daf |
1 | package stemmaweb::Authentication::Credential::Google; |
2 | |
3 | use Crypt::OpenSSL::X509; |
4 | use JSON::WebToken; |
5 | use IO::All; |
6 | use JSON::MaybeXS; |
7 | use MIME::Base64; |
8 | use LWP::Simple qw(get); |
9 | use Date::Parse qw(str2time); |
10 | |
11 | use warnings; |
12 | use strict; |
13 | use strictures 1; |
14 | |
15 | =head1 NAME |
16 | |
17 | stemmaweb::Authentication::Google - JSON Web Token handler for Google tokens. |
18 | |
19 | =head1 DESCRIPTION |
20 | |
21 | Retrieves Google's public certificates, and then retrieves the key from the |
22 | cert using L<Crypt::OpenSSL::X509>. Finally, uses the pubkey to decrypt a |
23 | Google token using L<JSON::WebToken>. |
24 | |
25 | =cut |
26 | |
27 | sub new { |
28 | my ($class, $config, $app, $realm) = @_; |
29 | $class = ref $class || $class; |
30 | |
31 | my $self = { |
32 | _config => $config, |
33 | _app => $app, |
34 | _realm => $realm, |
35 | }; |
36 | |
37 | bless $self, $class; |
38 | } |
39 | |
40 | sub authenticate { |
41 | my ($self, $c, $realm, $authinfo) =@_; |
42 | |
43 | my $id_token = $authinfo->{id_token}; |
44 | $id_token ||= $c->req->method eq 'GET' ? |
45 | $c->req->query_params->{id_token} : $c->req->body_params->{id_token}; |
46 | |
85990daf |
47 | if (!$id_token) { |
48 | Catalyst::Exception->throw("id_token not specified."); |
49 | } |
50 | |
51 | my $userinfo = $self->decode($id_token); |
52 | |
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53 | my $sub = $userinfo->{sub}; |
54 | my $openid = $userinfo->{openid_id}; |
55 | |
85990daf |
56 | if (!$sub || !$openid) { |
57 | Catalyst::Exception->throw( |
58 | 'Could not retrieve sub and openid from token! Is the token |
59 | correct?' |
60 | ); |
61 | } |
62 | |
83ed6665 |
63 | return $realm->find_user($userinfo, $c); |
85990daf |
64 | } |
65 | |
66 | =head1 METHODS |
67 | |
68 | =head2 retrieve_certs |
69 | |
70 | Retrieves a pair of JSON-encoded certificates from the given URL (defaults to |
71 | Google's public cert url), and returns the decoded JSON object. |
72 | |
73 | =head3 ARGUMENTS |
74 | |
75 | =over |
76 | |
77 | =item url |
78 | |
79 | Optional. Location where certificates are located. |
80 | Defaults to https://www.googleapis.com/oauth2/v1/certs. |
81 | |
82 | =back |
83 | |
84 | =head3 RETURNS |
85 | |
86 | Decoded JSON object containing certificates. |
87 | |
88 | =cut |
89 | |
90 | sub retrieve_certs { |
91 | my ($self, $url) = @_; |
92 | |
82be740c |
93 | $url ||= ( $self->{_app}->config->{'Authentication::Credential::Google'}->{public_cert_url} || 'https://www.googleapis.com/oauth2/v1/certs' ); |
85990daf |
94 | return decode_json(get($url)); |
95 | } |
96 | |
97 | =head2 get_key_from_cert |
98 | |
99 | Given a pair of certificates $certs (defaults to L</retrieve_certs>), |
100 | this function returns the public key of the cert identified by $kid. |
101 | |
102 | =head3 ARGUMENTS |
103 | |
104 | =over |
105 | |
106 | =item $kid |
107 | |
108 | Required. Index of the certificate hash $hash where the cert we want is |
109 | located. |
110 | |
111 | =item $certs |
112 | |
113 | Optional. A (hashref) pair of certificates. |
114 | It's retrieved using L</retrieve_certs> if not given, |
115 | or if the pair is expired. |
116 | |
117 | =back |
118 | |
119 | =head3 RETURNS |
120 | |
121 | Public key of certificate. |
122 | |
123 | =cut |
124 | |
125 | sub get_key_from_cert { |
126 | my ($self, $kid, $certs) = @_; |
127 | |
128 | $certs ||= $self->retrieve_certs; |
129 | my $cert = $certs->{$kid}; |
130 | my $x509 = Crypt::OpenSSL::X509->new_from_string($cert); |
131 | |
132 | if ($self->is_cert_expired($x509)) { |
133 | # If we ended up here, we were given |
134 | # an old $certs string from the user. |
135 | # Let's force getting another. |
136 | return $self->get_key_from_cert($kid); |
137 | } |
138 | |
139 | return $x509->pubkey; |
140 | } |
141 | |
142 | =head2 is_cert_expired |
143 | |
144 | Returns if a given L<Crypt::OpenSSL::X509> certificate is expired. |
145 | |
146 | =cut |
147 | |
148 | sub is_cert_expired { |
149 | my ($self, $x509) = @_; |
150 | |
151 | my $expiry = str2time($x509->notAfter); |
152 | |
153 | return time > $expiry; |
154 | } |
155 | |
156 | =head2 decode |
157 | |
158 | Returns the decoded information contained in a user's token. |
159 | |
160 | =head3 ARGUMENTS |
161 | |
162 | =over |
163 | |
164 | =item $token |
165 | |
166 | Required. The user's token from Google+. |
167 | |
168 | =item $pubkey |
169 | |
170 | Optional. A public key string with which to decode the token. |
171 | If not given, the public key will be retrieved from $certs. |
172 | |
173 | =item $certs |
174 | |
175 | Optional. A pair of public key certs retrieved from Google. |
176 | If not given, or if the certificates have expired, a new |
177 | pair of certificates is retrieved. |
178 | |
179 | =back |
180 | |
181 | =head2 RETURNS |
182 | |
183 | Decoded JSON object from the decrypted token. |
184 | |
185 | =cut |
186 | |
187 | sub decode { |
188 | my ($self, $token, $certs, $pubkey) = @_; |
189 | |
190 | if (!$pubkey) { |
191 | my $details = decode_json( |
192 | MIME::Base64::decode_base64( |
193 | substr( $token, 0, CORE::index($token, '.') ) |
194 | ) |
195 | ); |
196 | |
197 | my $kid = $details->{kid}; |
198 | $pubkey = $self->get_key_from_cert($kid, $certs); |
199 | } |
200 | |
201 | return JSON::WebToken->decode($token, $pubkey); |
202 | } |
203 | |
204 | =head1 AUTHOR |
205 | |
206 | Errietta Kostala <e.kostala@shadowcat.co.uk> |
207 | |
208 | =head1 LICENSE |
209 | |
210 | This library is free software. You can redistribute it and/or modify |
211 | it under the same terms as Perl itself. |
212 | |
213 | =cut |
214 | |
215 | 1; |