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..
68 Create object (via Class::Accessor).
74 return $class->SUPER::new();
79 my $token = $tokenizer->generate({ length => 20 });
80 my $csrf_token = $tokenizer->generate({
81 type => 'CSRF', id => $id, secret => $secret,
83 my $jwt = $tokenizer->generate({
84 type => 'JWT, id => $id, secret => $secret,
87 Generate several types of tokens. Now includes CSRF.
88 For non-CSRF tokens an optional pattern parameter overrides length.
89 Room for future extension.
91 Pattern parameter could be write down using this subset of regular expressions:
92 \w Alphanumeric + "_".
94 \W Printable characters other than those in \w.
95 \D Printable characters other than those in \d.
96 . Printable characters.
106 my ( $self, $params ) = @_;
107 if( $params->{type} && $params->{type} eq 'CSRF' ) {
108 $self->{lasttoken} = _gen_csrf( $params );
109 } elsif( $params->{type} && $params->{type} eq 'JWT' ) {
110 $self->{lasttoken} = _gen_jwt( $params );
112 $self->{lasttoken} = _gen_rand( $params );
114 return $self->{lasttoken};
119 Like: generate({ type => 'CSRF', ... })
120 Note: id defaults to userid from context, secret to database password.
121 session_id is mandatory; it is combined with id.
126 my ( $self, $params ) = @_;
127 return if !$params->{session_id};
128 $params = _add_default_csrf_params( $params );
129 return $self->generate({ %$params, type => 'CSRF' });
134 Like: generate({ type => 'JWT', ... })
135 Note that JWT is designed to encode a structure but here we are actually only allowing a value
136 that will be store in the key 'id'.
141 my ( $self, $params ) = @_;
142 return if !$params->{id};
143 $params = _add_default_jwt_params( $params );
144 return $self->generate({ %$params, type => 'JWT' });
149 my $result = $tokenizer->check({
150 type => 'CSRF', id => $id, token => $token,
153 Check several types of tokens. Now includes CSRF.
154 Room for future extension.
159 my ( $self, $params ) = @_;
160 if( $params->{type} && $params->{type} eq 'CSRF' ) {
161 return _chk_csrf( $params );
163 elsif( $params->{type} && $params->{type} eq 'JWT' ) {
164 return _chk_jwt( $params );
171 Like: check({ type => 'CSRF', ... })
172 Note: id defaults to userid from context, secret to database password.
173 session_id is mandatory; it is combined with id.
178 my ( $self, $params ) = @_;
179 return if !$params->{session_id};
180 $params = _add_default_csrf_params( $params );
181 return $self->check({ %$params, type => 'CSRF' });
186 Like: check({ type => 'JWT', id => $id, token => $token })
188 Will return true if the token contains the passed id
193 my ( $self, $params ) = @_;
194 $params = _add_default_jwt_params( $params );
195 return $self->check({ %$params, type => 'JWT' });
200 $tokenizer->decode_jwt({ type => 'JWT', token => $token })
202 Will return the value of the id stored in the token.
206 my ( $self, $params ) = @_;
207 $params = _add_default_jwt_params( $params );
208 return _decode_jwt( $params );
211 # --- Internal routines ---
213 sub _add_default_csrf_params {
215 $params->{session_id} //= '';
216 if( !$params->{id} ) {
217 $params->{id} = Encode::encode( 'UTF-8', C4::Context->userenv->{id} . $params->{session_id} );
219 $params->{id} .= $params->{session_id};
221 $params->{id} //= Encode::encode( 'UTF-8', C4::Context->userenv->{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