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} : $c->req->body_params->{id_token}; |
46 | |
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47 | if (!$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 = $userinfo->{openid_id}; |
55 | |
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56 | if (!$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, $c); |
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64 | } |
65 | |
66 | =head1 METHODS |
67 | |
68 | =head2 retrieve_certs |
69 | |
70 | Retrieves a pair of JSON-encoded certificates from the given URL (defaults to |
71 | Google's public cert url), and returns the decoded JSON object. |
72 | |
73 | =head3 ARGUMENTS |
74 | |
75 | =over |
76 | |
77 | =item url |
78 | |
79 | Optional. Location where certificates are located. |
80 | Defaults to https://www.googleapis.com/oauth2/v1/certs. |
81 | |
82 | =back |
83 | |
84 | =head3 RETURNS |
85 | |
86 | Decoded JSON object containing certificates. |
87 | |
88 | =cut |
89 | |
90 | sub retrieve_certs { |
91 | my ($self, $url) = @_; |
92 | |
e490a3d8 |
93 | my $c = $self->{_app}; |
94 | my $cached = 0; |
95 | my $certs; |
96 | my $cache; |
97 | |
98 | $url ||= ( $c->config->{'Authentication::Credential::Google'}->{public_cert_url} || 'https://www.googleapis.com/oauth2/v1/certs' ); |
99 | |
100 | if ( ($c->registered_plugins('Catalyst::Plugin::Cache')) && ($cache = $c->cache) ) { |
101 | if ($certs = $cache->get('certs')) { |
102 | $certs = decode_json($certs); |
103 | |
104 | foreach my $key (keys %$certs) { |
105 | my $cert = $certs->{$key}; |
106 | my $x509 = Crypt::OpenSSL::X509->new_from_string($cert); |
107 | |
108 | if ($self->is_cert_expired($x509)) { |
109 | $cached = 0; |
110 | last; |
111 | } else { |
112 | $cached = 1; |
113 | } |
114 | } |
115 | } |
116 | } |
117 | |
118 | if (!$cached) { |
119 | my $certs_encoded = get($url); |
120 | |
121 | if ($cache) { |
122 | $cache->set('certs', $certs_encoded); |
123 | } |
124 | |
125 | $certs = decode_json($certs_encoded); |
126 | } |
127 | |
128 | return $certs; |
85990daf |
129 | } |
130 | |
131 | =head2 get_key_from_cert |
132 | |
133 | Given a pair of certificates $certs (defaults to L</retrieve_certs>), |
134 | this function returns the public key of the cert identified by $kid. |
135 | |
136 | =head3 ARGUMENTS |
137 | |
138 | =over |
139 | |
140 | =item $kid |
141 | |
142 | Required. Index of the certificate hash $hash where the cert we want is |
143 | located. |
144 | |
145 | =item $certs |
146 | |
147 | Optional. A (hashref) pair of certificates. |
148 | It's retrieved using L</retrieve_certs> if not given, |
149 | or if the pair is expired. |
150 | |
151 | =back |
152 | |
153 | =head3 RETURNS |
154 | |
155 | Public key of certificate. |
156 | |
157 | =cut |
158 | |
159 | sub get_key_from_cert { |
160 | my ($self, $kid, $certs) = @_; |
161 | |
162 | $certs ||= $self->retrieve_certs; |
163 | my $cert = $certs->{$kid}; |
164 | my $x509 = Crypt::OpenSSL::X509->new_from_string($cert); |
165 | |
166 | if ($self->is_cert_expired($x509)) { |
167 | # If we ended up here, we were given |
168 | # an old $certs string from the user. |
169 | # Let's force getting another. |
170 | return $self->get_key_from_cert($kid); |
171 | } |
172 | |
173 | return $x509->pubkey; |
174 | } |
175 | |
176 | =head2 is_cert_expired |
177 | |
178 | Returns if a given L<Crypt::OpenSSL::X509> certificate is expired. |
179 | |
180 | =cut |
181 | |
182 | sub is_cert_expired { |
183 | my ($self, $x509) = @_; |
184 | |
185 | my $expiry = str2time($x509->notAfter); |
186 | |
187 | return time > $expiry; |
188 | } |
189 | |
190 | =head2 decode |
191 | |
192 | Returns the decoded information contained in a user's token. |
193 | |
194 | =head3 ARGUMENTS |
195 | |
196 | =over |
197 | |
198 | =item $token |
199 | |
200 | Required. The user's token from Google+. |
201 | |
202 | =item $pubkey |
203 | |
204 | Optional. A public key string with which to decode the token. |
205 | If not given, the public key will be retrieved from $certs. |
206 | |
207 | =item $certs |
208 | |
209 | Optional. A pair of public key certs retrieved from Google. |
210 | If not given, or if the certificates have expired, a new |
211 | pair of certificates is retrieved. |
212 | |
213 | =back |
214 | |
215 | =head2 RETURNS |
216 | |
217 | Decoded JSON object from the decrypted token. |
218 | |
219 | =cut |
220 | |
221 | sub decode { |
222 | my ($self, $token, $certs, $pubkey) = @_; |
223 | |
224 | if (!$pubkey) { |
225 | my $details = decode_json( |
226 | MIME::Base64::decode_base64( |
227 | substr( $token, 0, CORE::index($token, '.') ) |
228 | ) |
229 | ); |
230 | |
231 | my $kid = $details->{kid}; |
232 | $pubkey = $self->get_key_from_cert($kid, $certs); |
233 | } |
234 | |
235 | return JSON::WebToken->decode($token, $pubkey); |
236 | } |
237 | |
238 | =head1 AUTHOR |
239 | |
240 | Errietta Kostala <e.kostala@shadowcat.co.uk> |
241 | |
242 | =head1 LICENSE |
243 | |
244 | This library is free software. You can redistribute it and/or modify |
245 | it under the same terms as Perl itself. |
246 | |
247 | =cut |
248 | |
249 | 1; |