# -*- perl -*-
+# This is part of CGI::Auth::Hybrid, a perl CGI authentication module.
+# Copyright (C) 2012 Ian Jackson.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+
BEGIN {
use Exporter ();
our ($VERSION, @ISA, @EXPORT, @EXPORT_OK, %EXPORT_TAGS);
}
our @EXPORT_OK;
-our %_s = (
- assocdb_path => 'cah-assocs.db';
- assocdb_dsn => undef,
- assocdb_user => '',
- assocdb_password => '',
- assocdb_table => 'assocs',
- random_source => '/dev/urandom',
- associdlen => 128, # bits
- param_name => 'cah_associd',
- cookie_name => 'cah_associd', # make undef to disable cookie
- param_get => sub { _c()->param($s_{param_name}) },
- cookie_get => sub { $_s{cookie_name} ? _c()->param($s_{cookie_name}) : '' },
- );
-
use DBI;
+use CGI;
-our $dbh;
+#---------- verifier object methods ----------
-sub new {
+sub new_verifier {
+ my $class = shift;
+ my $s = {
+ S => {
+ assocdb_path => 'cah-assocs.db';
+ assocdb_dsn => undef,
+ assocdb_user => '',
+ assocdb_password => '',
+ assocdb_table => 'assocs',
+ random_source => '/dev/urandom',
+ associdlen => 128, # bits
+ login_timeout => 86400, # seconds
+ param_name => 'cah_associd',
+ promise_check_mutate => 0,
+ cookie_name => 'cah_associd', # make undef to disable cookie
+ get_param => sub { $_[0]->param($s->{S}{param_name}) },
+ get_cookie => sub { $s->{S}{cookie_name}
+ ? $_[0]->cookie($s->{S}{cookie_name})
+ : '' },
+ get_method => sub { $_[0]->request_method() },
+ },
+ Dbh => undef,
+ };
my ($k,$v);
while (($k,$v,@_) = @_) {
- die "unknown setting $k" unless %_s{$k};
- $_s{$k} = $v;
+ die "unknown setting $k" unless exists $s->{S}{$k};
+ $s->{S}{$k} = $v;
}
+ bless $s, $class;
+ $s->_dbopen();
+ return $s;
}
-sub _dbopen () {
- return if $dbh;
+sub _dbopen ($) {
+ my ($s) = @_;
+ my $dbh = $s->{Dbh};
+ return $dbh if $dbh;
- $_s{assocdb_dsn}="dbi:SQLite:dbname=$s_{assocdb_path}"
- if !$_s{assocdb_dsn};
+ $s->{S}{assocdb_dsn} ||= "dbi:SQLite:dbname=$s->{S}{assocdb_path}";
my $u = umask 077;
- $dbh = DBI->open($_s{assocdb_dsn}, $s_{assocdb_user},
- $s_{assocdb_password}, {
+ $dbh = DBI->open($s->{S}{assocdb_dsn}, $s->{S}{assocdb_user},
+ $s->{S}{assocdb_password}, {
AutoCommit => 0, RaiseError => 1,
});
die "${assocdb_dsn} $! ?" unless $dbh;
+ $s->{Dbh} = $dbh;
$dbh->do("BEGIN");
eval {
- $dbh->do("CREATE TABLE $_s{assocdb_table} (".
+ $dbh->do("CREATE TABLE $s->{S}{assocdb_table} (".
" associd VARCHAR PRIMARY KEY,".
- " username VARCHAR".
+ " username VARCHAR,".
+ " last INTEGER"
")");
};
+ return $dbh;
+}
+
+#---------- request object methods ----------
+
+sub new_request {
+ my ($classbase, $cgi, @extra) = @_;
+ if (!ref $classbase) {
+ $classbase = $classbase->new_verifier(@extra);
+ } else {
+ die if @extra;
+ }
+ my $r = {
+ S => $classbase->{S},
+ Dbh => $classbase->{Dbh},
+ Cgi => $cgi,
+ };
+ bless $r, ref $classbase;
+}
+
+sub _cm ($$@) {
+ my ($r,$methname, @args) = @_;
+ my $methfunc = $r->{S}{$methname};
+ return $methfunc->($r->{Cgi}, $r, @args);
}
-sub record_login ($) {
- my ($nusername) = @_;
- my $rs = new IO::File $_s{random_source}, '<'
- or die "$_s{random_source} $!";
- my $bytes = ($_s{associdlen} + 7) >> 3;
+sub record_login ($$) {
+ my ($r,$nusername) = @_;
+ my $rsp = $r->{S}{random_source};
+ my $rsf = new IO::File $rsp, '<' or die "$rsp $!";
+ my $bytes = ($r->{S}{associdlen} + 7) >> 3;
my $nassocbin;
$!=0;
- read($rs,$nassocbin,$bytes) == $bytes or die "$s_{random_source} $!";
+ read($rsf,$nassocbin,$bytes) == $bytes or die "$rsp $!";
+ close $rsf;
my $nassoc = unpack "H*", $nassocbin;
- _dbopen();
- $dbh->do("INSERT INTO $_s{assocdb_table}".
- " (associd, username) VALUES (?,?)", {},
- $nassoc, $nusername);
+ my $dbh = $r->{Dbh};
+ $dbh->do("INSERT INTO $r->{S}{assocdb_table}".
+ " (associd, username, last) VALUES (?,?,?)", {},
+ $nassoc, $nusername, time);
+ $dbh->do("COMMIT");
+ $r->{U} = $nusername;
+ $r->{A} = $nassoc;
+}
+
+sub _check_core ($) {
+ my ($r) = @_;
+ my $qassoc = $r->_cm('get_param');
+ my ($nassoc,$nmutate);
+ if (!defined $r->{S}{cookie_name}) {
+ # authentication is by hidden form parameter only
+ return undef unless defined $qassoc;
+ $nassoc = $qassoc;
+ $nmutate = 1;
+ } else {
+ # authentication is by cookie
+ # the cookie suffices for read-only GET requests
+ # for mutating and non-GET requests we require hidden param too
+ my $cassoc = $r->_cm('get_cookie');
+ return undef unless defined $cassoc;
+ $nassoc = $cassoc;
+ if (defined $qassoc && $qassoc eq $cassoc) {
+ $nmutate = 1;
+ } else {
+ return undef unless $r->{S}{promise_check_mutate};
+ return undef unless $r->_cm('get_method') eq 'GET';
+ $nmutate = 0;
+ }
+ }
+
+# pages/param-sets are
+# n normal non-mutating page
+# r retrieval of information for JS, non-mutating
+# m mutating page
+# u update of information by JS, mutating
+# i login
+# o logout
+
+ # Case analysis, cookie mode, app promises re mutate:
+ # cook par meth form
+ #
+ # y y GET nr fine, show page or send data
+ #
+ # y - GET n cross-site link
+ # show data
+ # y1 y2 GET n intra-site link
+ # from session no longer known to browser
+ # do not revoke y2 as not a POST so not RESTful
+ # treat as cross-site link, show data
+ # y n GET n intra-site link from stale session,
+ # treat as cross-site link, show data
+ #
+ # y - GET r bug or attack, fail
+ # y1 y2 GET r intra-site data request
+ # from session no longer known to browser
+ # do not revoke y2 as not a POST so not RESTful
+ # fail
+ # y n GET r intra-site data request from stale session
+ # fail
+ #
+ # - y GET n CLEAR COOKIES TO LOGOUT OPTION
+ #
+ # -/n any GET n cross-site link but user not logged in
+ # show login form
+ #
+ # -/n any GET r data request from stale session
+ # fail
+ #
+ # any any GET muoi bug or attack, fail
+ #
+ # y y POST nrmu mutation is OK, do operation
+ # y y POST o logout
+ # y y POST i login, redirect to GET of remaining params
+ #
+ # any - POST bug or xsrf attack, fail
+ #
+ # n/y1 y2 POST r intra-site form submission
+ # from session no longer known to browser
+ # revoke y2
+ # show "session interrupted"
+ # n/y1 y2 POST m intra-site js operation
+ # from session no longer known to browser
+ # revoke y2
+ # fail
+ # y n POST r intra-site form submission from stale session
+ # show "session interrupted"
+ # y n POST m intra-site form submission from stale session
+ # fail
+ #
+ # - y2 GET intra-site link or data request
+ # from session no longer known to browser
+ # fail
+
+ # - y2 any req from old session y2, del y2, show login
+ # y1 y2 any req from old session y2, del y2, show y1 main
+
+ # y1 any GET non-mut cross-site link
+ # y1 any GET non-mut no mutation, show page providing new par
+ #
+ # A B any page from old session or cross-site request
+ # any y2 POST logout do logout y2
+
+
+ # any any GET mutate bug or attack, forbidden, call die
+
+ my $dbh = $r->{Dbh};
+ my ($nusername, $nlast) =
+ $dbh->selectrow_array("SELECT username, last".
+ " FROM $r->{S}{assocdb_table}".
+ " WHERE associd = ?", {}, $nassoc);
+ return undef unless defined $nusername;
+ my $timeout = $r->{S}{login_timeout};
+ return undef unless !defined $timeout || time <= $nlast + $timeout;
+
+ # hooray
+ return ($nusername, $nassoc, $nmutate);
+}
+
+sub _check ($) {
+ my ($r) = @_;
+
+ return if exists $r->{Username};
+ ($r->{Username}, $r->{Assoc}, $r->{Mutate}) = $r->_check();
+
+ if (defined $r->{Assoc}) {
+ $dbh->do("UPDATE $r->{S}{assocdb_table}".
+ " SET last = ?".
+ " WHERE associd = ?", {}, time, $nassoc);
+ $dbh->do("COMMIT");
+ }
+}
+
+sub logout ($) {
+ my ($r) = @_;
+
+ my ($nusername, $nassoc, $nmutate) = $r->_check();
+ return undef unless $nmutate;
+ $dbh->do("DELETE FROM $r->{S}{assocdb_table}".
+ " WHERE associd = ?", {}, $nassoc);
$dbh->do("COMMIT");
- $username = $nusername;
- $assoc = $nassoc;
+ return $nusername;
+}
+
+sub check ($) {
+ my ($r) = @_;
+ $r->_check();
+ return !!defined $r->{Username};
+}
+
+sub check_mutate ($) {
+ my ($r) = @_;
+ $r->check();
+ return $r->{Mutate};
+}
+
+sub username ($) {
+ my ($r) = @_;
+ $r->check();
+ return $r->{Username};
+
+sub hidden_val ($) {
+ my ($r) = @_;
+ $r->check();
+ return defined $r->{Assoc} ? $r->{Assoc} : '';
+}
+
+#---------- simple wrappers ----------
+
+sub hidden_hargs ($) {
+ my ($r) = @_;
+ return (-name => $r->{S}{param_name},
+ -default => $r->hidden_val());
+}
+
+sub hidden_html ($) {
+ my ($r) = @_;
+ return hidden($r->hidden_hargs());
}
-sub check () {
- my $passocid = $_s{param_get}();
- my $cassocid = $_s{cookie_get}();
- if (
+sub cookiea_cargs ($) {
+ my ($r) = @_;
+ return (-name => $r->{S}{cookie_name},
+ -value => hidden_val());
+}
+
+__END__
+
+=head1 NAME
+
+CGI::Auth::Hybrid - web authentication optionally using cookies
+
+=head1 SYNOPSYS
+
+ my $verifier = CGI::Auth::Hybrid->new_verifier(setting => value,...);
+ my $authreq = $verifier->new_request($cgi_request_object);
+
+ my $authreq = CGI::Auth::Hybrid->new_request($cgi_request_object,
+ setting => value,...);
+
+=head1 USAGE PATTERN FOR SIMPLE APPLICATIONS
+
+ if ( form submission is login request ) {
+ check login details, if wrong print error and quit
+ $authreq->record_login(...username...);
+ }
+ if ( form submission is logout request ) {
+ my $logged_out_user = $authreq->logout();
+ if (!defined $logged_out_user) {
+ print "you are not logged in" error and quit
+ } else {
+ print "goodbye $username you are now logged out" and quit
+ }
+ }
+ if ( !$authreq->check() ) {
+ display login form, quit
+
+
+=head1 USAGE PATTERN FOR FANCY APPLICATIONS
+
+ if ( form submission is login request ) {
+ check login details, if wrong print error and quit
+ $authreq->record_login(...username...);
+ }
+ if ( !$authreq->check() ) {
+ display login form, quit
+ if ( form submission is logout request ) {
+ die unless $authreq->mutate();
+ my $logged_out_user = $authreq->logout();
+ if (!defined $logged_out_user) {
+ print "you are not logged in" error and quit
+ } else {
+ print "goodbye $username you are now logged out" and quit
+ }
+ }
+
+
+advantages of cookie
+ - user can sort of log out by clearing cookies
+ - sophisticated applications can have get-requests