3 # Created as wrapper for CSRF and JWT tokens, but designed for more general use
5 # Copyright 2016 Rijksmuseum
7 # This file is part of Koha.
9 # Koha is free software; you can redistribute it and/or modify it
10 # under the terms of the GNU General Public License as published by
11 # the Free Software Foundation; either version 3 of the License, or
12 # (at your option) any later version.
14 # Koha is distributed in the hope that it will be useful, but
15 # WITHOUT ANY WARRANTY; without even the implied warranty of
16 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 # GNU General Public License for more details.
19 # You should have received a copy of the GNU General Public License
20 # along with Koha; if not, see <http://www.gnu.org/licenses>.
24 Koha::Token - Tokenizer
29 my $tokenizer = Koha::Token->new;
30 my $token = $tokenizer->generate({ length => 20 });
32 # safely generate a CSRF token (nonblocking)
33 my $csrf_token = $tokenizer->generate({
34 type => 'CSRF', id => $id, secret => $secret,
37 # generate/check CSRF token with defaults and session id
38 my $csrf_token = $tokenizer->generate_csrf({ session_id => $x });
39 my $result = $tokenizer->check_csrf({
40 session_id => $x, token => $token,
45 Designed for providing general tokens.
46 Created due to the need for a nonblocking call to Bytes::Random::Secure
47 when generating a CSRF token.
52 use Bytes::Random::Secure;
56 use Digest::MD5 qw( md5_base64 );
59 use Koha::Exceptions::Token;
60 use base qw(Class::Accessor);
61 use constant HMAC_SHA1_LENGTH => 20;
62 use constant CSRF_EXPIRY_HOURS => 8; # 8 hours instead of 7 days..
63 use constant DEFA_SESSION_ID => 0;
64 use constant DEFA_SESSION_USERID => 'anonymous';
70 Create object (via Class::Accessor).
76 return $class->SUPER::new();
81 my $token = $tokenizer->generate({ length => 20 });
82 my $csrf_token = $tokenizer->generate({
83 type => 'CSRF', id => $id, secret => $secret,
85 my $jwt = $tokenizer->generate({
86 type => 'JWT, id => $id, secret => $secret,
89 Generate several types of tokens. Now includes CSRF.
90 For non-CSRF tokens an optional pattern parameter overrides length.
91 Room for future extension.
93 Pattern parameter could be write down using this subset of regular expressions:
94 \w Alphanumeric + "_".
96 \W Printable characters other than those in \w.
97 \D Printable characters other than those in \d.
98 . Printable characters.
108 my ( $self, $params ) = @_;
109 if( $params->{type} && $params->{type} eq 'CSRF' ) {
110 $self->{lasttoken} = _gen_csrf( $params );
111 } elsif( $params->{type} && $params->{type} eq 'JWT' ) {
112 $self->{lasttoken} = _gen_jwt( $params );
114 $self->{lasttoken} = _gen_rand( $params );
116 return $self->{lasttoken};
121 Like: generate({ type => 'CSRF', ... })
122 Note: id defaults to userid from context, secret to database password.
123 session_id is mandatory; it is combined with id.
128 my ( $self, $params ) = @_;
129 return if !$params->{session_id};
130 $params = _add_default_csrf_params( $params );
131 return $self->generate({ %$params, type => 'CSRF' });
136 Like: generate({ type => 'JWT', ... })
137 Note that JWT is designed to encode a structure but here we are actually only allowing a value
138 that will be store in the key 'id'.
143 my ( $self, $params ) = @_;
144 return if !$params->{id};
145 $params = _add_default_jwt_params( $params );
146 return $self->generate({ %$params, type => 'JWT' });
151 my $result = $tokenizer->check({
152 type => 'CSRF', id => $id, token => $token,
155 Check several types of tokens. Now includes CSRF.
156 Room for future extension.
161 my ( $self, $params ) = @_;
162 if( $params->{type} && $params->{type} eq 'CSRF' ) {
163 return _chk_csrf( $params );
165 elsif( $params->{type} && $params->{type} eq 'JWT' ) {
166 return _chk_jwt( $params );
173 Like: check({ type => 'CSRF', ... })
174 Note: id defaults to userid from context, secret to database password.
175 session_id is mandatory; it is combined with id.
180 my ( $self, $params ) = @_;
181 return if !$params->{session_id};
182 $params = _add_default_csrf_params( $params );
183 return $self->check({ %$params, type => 'CSRF' });
188 Like: check({ type => 'JWT', id => $id, token => $token })
190 Will return true if the token contains the passed id
195 my ( $self, $params ) = @_;
196 $params = _add_default_jwt_params( $params );
197 return $self->check({ %$params, type => 'JWT' });
202 $tokenizer->decode_jwt({ type => 'JWT', token => $token })
204 Will return the value of the id stored in the token.
208 my ( $self, $params ) = @_;
209 $params = _add_default_jwt_params( $params );
210 return _decode_jwt( $params );
213 # --- Internal routines ---
215 sub _add_default_csrf_params {
217 $params->{session_id} //= DEFA_SESSION_ID;
218 my $userenv = C4::Context->userenv // { id => DEFA_SESSION_USERID };
219 $params->{id} //= Encode::encode( 'UTF-8', $userenv->{id} );
220 $params->{id} .= '_' . $params->{session_id};
222 my $pw = C4::Context->config('pass');
223 $params->{secret} //= md5_base64( Encode::encode( 'UTF-8', $pw ) ),
229 # Since WWW::CSRF::generate_csrf_token does not use the NonBlocking
230 # parameter of Bytes::Random::Secure, we are passing random bytes from
231 # a non blocking source to WWW::CSRF via its Random parameter.
234 return if !$params->{id} || !$params->{secret};
237 my $randomizer = Bytes::Random::Secure->new( NonBlocking => 1 );
238 # this is most fundamental: do not use /dev/random since it is
239 # blocking, but use /dev/urandom !
240 my $random = $randomizer->bytes( HMAC_SHA1_LENGTH );
241 my $token = WWW::CSRF::generate_csrf_token(
242 $params->{id}, $params->{secret}, { Random => $random },
250 return if !$params->{id} || !$params->{secret} || !$params->{token};
252 my $csrf_status = WWW::CSRF::check_csrf_token(
256 { MaxAge => $params->{MaxAge} // ( CSRF_EXPIRY_HOURS * 3600 ) },
258 return $csrf_status == WWW::CSRF::CSRF_OK();
263 my $length = $params->{length} || 1;
264 $length = 1 unless $length > 0;
265 my $pattern = $params->{pattern} // '.{'.$length.'}'; # pattern overrides length parameter
269 $token = String::Random::random_regex( $pattern );
271 Koha::Exceptions::Token::BadPattern->throw($@) if $@;
275 sub _add_default_jwt_params {
277 my $pw = C4::Context->config('pass');
278 $params->{secret} //= md5_base64( Encode::encode( 'UTF-8', $pw ) ),
284 return if !$params->{id} || !$params->{secret};
286 return Mojo::JWT->new(
287 claims => { id => $params->{id} },
288 secret => $params->{secret}
294 return if !$params->{id} || !$params->{secret} || !$params->{token};
296 my $claims = Mojo::JWT->new(secret => $params->{secret})->decode($params->{token});
298 return 1 if exists $claims->{id} && $claims->{id} == $params->{id};
303 return if !$params->{token} || !$params->{secret};
305 my $claims = Mojo::JWT->new(secret => $params->{secret})->decode($params->{token});
307 return $claims->{id};
312 Marcel de Rooy, Rijksmuseum Amsterdam, The Netherlands