# -*- 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;
use DBI;
+use CGI;
+
+#---------- default callbacks ----------
+
+sub _def_is_logout ($$) {
+ my ($c,$r) = @_;
+ foreach my $pn (@{ $r->{S}{logout_param_names} }) {
+ return 1 if $r->_cm('get_param')($pn);
+ }
+ return 0;
+}
-sub new {
+#---------- verifier object methods ----------
+
+sub new_verifier {
my $class = shift;
my $s = {
S => {
assocdb_table => 'assocs',
random_source => '/dev/urandom',
associdlen => 128, # bits
- param_name => 'cah_associd',
- cookie_name => 'cah_associd', # make undef to disable cookie
- cgi => undef,
- get_param => sub { $s->_c()->param($s->{S}{param_name}) },
- get_cookie => sub { $s->{S}{cookie_name}
- ? $s->_c()->cookie($s->{S}{cookie_name})
- : '' },
- get_method => sub { $s->_c()->request_method() },
+ login_timeout => 86400, # seconds
+ assoc_param_name => 'cah_associd',
+ password_param_name => 'password',
+ logout_param_names => [qw(logout)],
+ promise_check_mutate => 0,
+ get_param => sub { $_[0]->param($_[2]) },
+ get_cah_cookie => sub { $_[0]->cookie($s->{S}{cookie_name}) },
+ get_method => sub { $_[0]->request_method() },
+ is_login => sub { defined $_[1]->_rp('password_param_name') },
+ login_ok => sub { die },
+ is_logout => \&_def_is_logout,
+ is_page => sub { return 1 },
},
- D => undef,
+ Dbh => undef,
};
my ($k,$v);
while (($k,$v,@_) = @_) {
$s->{S}{$k} = $v;
}
bless $s, $class;
+ $s->_dbopen();
return $s;
}
-sub _c ($) {
- my ($s) = @_;
- return $s->{S}{cgi};
-}
-
sub _dbopen ($) {
my ($s) = @_;
- my $dbh = $s->{D};
+ my $dbh = $s->{Dbh};
return $dbh if $dbh;
$s->{S}{assocdb_dsn} ||= "dbi:SQLite:dbname=$s->{S}{assocdb_path}";
AutoCommit => 0, RaiseError => 1,
});
die "${assocdb_dsn} $! ?" unless $dbh;
- $s->{D} = $dbh;
+ $s->{Dbh} = $dbh;
$dbh->do("BEGIN");
eval {
$dbh->do("CREATE TABLE $s->{S}{assocdb_table} (".
- " associd VARCHAR PRIMARY KEY,".
- " username VARCHAR".
+ " associdh VARCHAR PRIMARY KEY,".
+ " username VARCHAR,".
+ " last INTEGER NOT NULL"
")");
};
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 _ch ($$@) { # calls an application hook
+ my ($r,$methname, @args) = @_;
+ my $methfunc = $r->{S}{$methname};
+ return $methfunc->($r->{Cgi}, $r, @args);
+}
+
+sub _rp ($$@) {
+ my ($r,$pnvb) = @_;
+ my $pn = $r->{S}{$pnvb};
+ my $p = $r->_ch('get_param',$pn)
+}
+
+# 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
+
+
+# in cook and par,
+# a, aN anything including -
+# t, tN temporary value (in our db, no logged in user yet)
+# y, yN value corresponds to logged-in user
+# n, nN value not in our db
+# x, xN t or y
+# - no value supplied
+# if N differs the case applies only when the two values differ
+# (eg, a1 y2 does not apply when the logged-in value is supplied twice)
+
+# "stale session" means request originates from a page from a login
+# session which has been revoked (eg by logout); "cleared session"
+# means request originates from a browser which has a different (or
+# no) cookie.
+
+ # Case analysis, cookie mode, app promises re mutate:
+ # cook parm meth form
+ #
+ # any - POST nrmuoi bug or attack, fail
+ # any - GET rmuoi bug or attack, fail
+ # any any GET muoi bug or attack, fail
+ # any t any nrmuo bug or attack, fail
+ #
+ # a1 a2 POST o logout
+ # if a1 is valid, revoke it
+ # if a2 is valid, revoke it
+ # delete cookie
+ # redirect to "just logged out" page
+ # (which contains link to login form)
+ #
+ # - t POST i complain about cookies being disabled
+ #
+ # any n POST i complain about stale login form
+ # show new login form
+ #
+ # x1 t2 POST i login (or switch user)
+ # revoke x1 if it was valid and !=t2
+ # upgrade t2 to y2 in our db (setting username)
+ # set cookie to t2
+ # redirect to GET of remaining params
+ #
+ # t1 a2 ANY nrmu treat as - a2 ANY
+ #
+ # y - GET n cross-site link
+ # show data
+ #
+ # y y GET nr fine, show page or send data
+ # y y POST nrmu mutation is OK, do operation
+ #
+ # y1 y2 GET nr request from stale page
+ # do not revoke y2 as not RESTful
+ # treat as y1 n GET
+ #
+ # y1 y2 POST nrmu request from stale page
+ # revoke y2
+ # treat as y1 n POST
+ #
+ # y n GET n intra-site link from stale page,
+ # treat as cross-site link, show data
+ #
+ # y n POST n m intra-site form submission from stale page
+ # show "session interrupted"
+ # with link to main data page
+ #
+ # y n GET r intra-site request from stale page
+ # fail
+ #
+ # y n POST r u intra-site request from stale page
+ # fail
+ #
+ # -/n y2 GET nr intra-site link from cleared session
+ # do not revoke y2 as not RESTful
+ # treat as -/n n GET
+ #
+ # -/n y2 POST nrmu request from cleared session
+ # revoke y2
+ # treat as -/n n POST
+ #
+ # -/n n GET n cross-site link but user not logged in
+ # show login form with redirect to orig params
+ #
+ # -/n n GET rmu user not logged in
+ # fail
+ #
+ # -/n n POST nrmu user not logged in
+ # fail
+
+sub check_divert ($) {
+ my ($r) = @_;
+
+ my $cookv = $r->_ch('get_cah_cookie');
+ my $parmv = $r->_rp('assoc_param_name');
+
+ my $cookt = $r->_db_lookup($cookv);
+ my $parmt = $r->_db_lookup($parmv);
+
+ if ($r->_ch('is_logout')) {
+ $r->_must_be_post();
+ die unless $parmt;
+ $r->_db_perhaps_revoke($cookv);
+ $r->_db_perhaps_revoke($parmv);
+ $r->_queue_set_cookie('');
+ return 'REDIRECT-LOGGEDOUT';
+ }
+ if ($r->_ch('is_login')) {
+ return 'NOCOOKIE' if !$cookt && $parmt eq 't';
+ return 'LOGIN-STALE' if $parmt eq 'n';
+ $r->_db_perhaps_revoke($cookv)
+ if defined $cookv && !(defined $parmv && $cookv eq $parmv);
+ $r->_queue_set_cookie($parmv);
+ my $username = $r->_ch('login_ok');
+ return 'LOGIN-BAD' unless defined $username && length $username;
+ $r->_db_record_login_ok($parmv,$username);
+ return 'REDIRECT-LOGGEDIN';
+ }
+ if (!$r->{S}{promise_check_mutate}) {
+ something with method get, check parameter, etc.
+ return 'FRONTPAGE';
+ }
+
+
+UP TO HERE
+
+sub _check_core ($) {
+ my ($r) = @_;
+ my $qassoc = $r->_ch('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->_ch('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->_ch('get_method') eq 'GET';
+ $nmutate = 0;
+ }
+ }
+
+ 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 record_login ($$) {
- my ($s,$nusername) = @_;
- my $rsp = $s->{S}{random_source};
+ my ($r,$nusername) = @_;
+ my $rsp = $r->{S}{random_source};
my $rsf = new IO::File $rsp, '<' or die "$rsp $!";
- my $bytes = ($s->{S}{associdlen} + 7) >> 3;
+ my $bytes = ($r->{S}{associdlen} + 7) >> 3;
my $nassocbin;
$!=0;
read($rsf,$nassocbin,$bytes) == $bytes or die "$rsp $!";
close $rsf;
my $nassoc = unpack "H*", $nassocbin;
- my $dbh = $s->_dbopen();
- $dbh->do("INSERT INTO $s->{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");
- $username = $nusername;
- $assoc = $nassoc;
+ $r->{U} = $nusername;
+ $r->{A} = $nassoc;
}
-sub check () {
- my $qassocid = $s->{S}{param_get}();
- if (!defined $qassocid) {
- $qassocid = $s->{S}{cookie_get}();
- return 0 unless defined $qassocid;
- return 0 unless $s->{S}{get_method}() eq 'GET';
+sub _check ($) {
+ 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");
+ 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 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
+
+ $authreq->check_ok() or return;
+
+ blah blah blah
+ $authreq->mutating();
+ blah blah blah
+
+=head1 USAGE PATTERN FOR FANCY APPLICATIONS
+
+ my $divert_kind = $authreq->check_divert();
+ if ($divert_kind) {
+ if ($divert_kind eq 'LOGGEDOUT') {
+ print "goodbye you are now logged out" and quit
+ } elsif ($divert_kind eq 'NOCOOKIES') {
+ print "you need cookies" and quit
+ ... etc.
+ }
+ }
+