3 # Created as wrapper for CSRF 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;
55 use Digest::MD5 qw( md5_base64 );
58 use Koha::Exceptions::Token;
59 use base qw(Class::Accessor);
60 use constant HMAC_SHA1_LENGTH => 20;
61 use constant CSRF_EXPIRY_HOURS => 8; # 8 hours instead of 7 days..
67 Create object (via Class::Accessor).
73 return $class->SUPER::new();
78 my $token = $tokenizer->generate({ length => 20 });
79 my $csrf_token = $tokenizer->generate({
80 type => 'CSRF', id => $id, secret => $secret,
83 Generate several types of tokens. Now includes CSRF.
84 For non-CSRF tokens an optional pattern parameter overrides length.
85 Room for future extension.
87 Pattern parameter could be write down using this subset of regular expressions:
88 \w Alphanumeric + "_".
90 \W Printable characters other than those in \w.
91 \D Printable characters other than those in \d.
92 . Printable characters.
102 my ( $self, $params ) = @_;
103 if( $params->{type} && $params->{type} eq 'CSRF' ) {
104 $self->{lasttoken} = _gen_csrf( $params );
106 $self->{lasttoken} = _gen_rand( $params );
108 return $self->{lasttoken};
113 Like: generate({ type => 'CSRF', ... })
114 Note: id defaults to userid from context, secret to database password.
115 session_id is mandatory; it is combined with id.
120 my ( $self, $params ) = @_;
121 return if !$params->{session_id};
122 $params = _add_default_csrf_params( $params );
123 return $self->generate({ %$params, type => 'CSRF' });
128 my $result = $tokenizer->check({
129 type => 'CSRF', id => $id, token => $token,
132 Check several types of tokens. Now includes CSRF.
133 Room for future extension.
138 my ( $self, $params ) = @_;
139 if( $params->{type} && $params->{type} eq 'CSRF' ) {
140 return _chk_csrf( $params );
147 Like: check({ type => 'CSRF', ... })
148 Note: id defaults to userid from context, secret to database password.
149 session_id is mandatory; it is combined with id.
154 my ( $self, $params ) = @_;
155 return if !$params->{session_id};
156 $params = _add_default_csrf_params( $params );
157 return $self->check({ %$params, type => 'CSRF' });
160 # --- Internal routines ---
162 sub _add_default_csrf_params {
164 $params->{session_id} //= '';
165 if( !$params->{id} ) {
166 $params->{id} = Encode::encode( 'UTF-8', C4::Context->userenv->{id} . $params->{session_id} );
168 $params->{id} .= $params->{session_id};
170 $params->{id} //= Encode::encode( 'UTF-8', C4::Context->userenv->{id} );
171 my $pw = C4::Context->config('pass');
172 $params->{secret} //= md5_base64( Encode::encode( 'UTF-8', $pw ) ),
178 # Since WWW::CSRF::generate_csrf_token does not use the NonBlocking
179 # parameter of Bytes::Random::Secure, we are passing random bytes from
180 # a non blocking source to WWW::CSRF via its Random parameter.
183 return if !$params->{id} || !$params->{secret};
186 my $randomizer = Bytes::Random::Secure->new( NonBlocking => 1 );
187 # this is most fundamental: do not use /dev/random since it is
188 # blocking, but use /dev/urandom !
189 my $random = $randomizer->bytes( HMAC_SHA1_LENGTH );
190 my $token = WWW::CSRF::generate_csrf_token(
191 $params->{id}, $params->{secret}, { Random => $random },
199 return if !$params->{id} || !$params->{secret} || !$params->{token};
201 my $csrf_status = WWW::CSRF::check_csrf_token(
205 { MaxAge => $params->{MaxAge} // ( CSRF_EXPIRY_HOURS * 3600 ) },
207 return $csrf_status == WWW::CSRF::CSRF_OK();
212 my $length = $params->{length} || 1;
213 $length = 1 unless $length > 0;
214 my $pattern = $params->{pattern} // '.{'.$length.'}'; # pattern overrides length parameter
218 $token = String::Random::random_regex( $pattern );
220 Koha::Exceptions::Token::BadPattern->throw($@) if $@;
226 Marcel de Rooy, Rijksmuseum Amsterdam, The Netherlands