X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ian/git?p=cgi-auth-flexible.git;a=blobdiff_plain;f=cgi-auth-hybrid.pm;h=3388b85cdf793730da2d8a65d8b4ef0cb3155c88;hp=c3cdbfb53e79890566b05075ade4d052b089e4ef;hb=8be9bfceabd19dfb7474de5707ec9ccb9dcea2d9;hpb=3e3b8c9743a67da9b387d2ccc0a55f8714a72d77

diff --git a/cgi-auth-hybrid.pm b/cgi-auth-hybrid.pm
index c3cdbfb..3388b85 100644
--- a/cgi-auth-hybrid.pm
+++ b/cgi-auth-hybrid.pm
@@ -32,6 +32,16 @@ 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;
+}
+
 #---------- verifier object methods ----------
 
 sub new_verifier {
@@ -46,14 +56,17 @@ sub new_verifier {
 	    random_source => '/dev/urandom',
 	    associdlen => 128, # bits
 	    login_timeout => 86400, # seconds
-	    param_name => 'cah_associd',
+	    assoc_param_name => 'cah_associd',
+	    password_param_name => 'password',
+	    logout_param_names => [qw(logout)],
 	    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_param => sub { $_[0]->param($_[2]) },
+	    get_cookie => sub { $_[0]->cookie($s->{S}{cookie_name}) },
 	    get_method => sub { $_[0]->request_method() },
+            is_login => sub { defined $_[1]->_rp('password_param_name') },
+            login_ok => sub { die },
+	    is_logout => \&_def_is_logout,
+	    is_page => sub { return 1 },
 	},
 	Dbh => undef,
     };
@@ -86,9 +99,9 @@ sub _dbopen ($) {
 
     eval {
 	$dbh->do("CREATE TABLE $s->{S}{assocdb_table} (".
-		 " associd VARCHAR PRIMARY KEY,".
+		 " associdh VARCHAR PRIMARY KEY,".
                  " username VARCHAR,".
-		 " last INTEGER"
+		 " last INTEGER NOT NULL"
 		 ")");
     };
     return $dbh;
@@ -111,34 +124,21 @@ sub new_request {
     bless $r, ref $classbase;
 }
 
-sub _cm ($$@) {
+sub _ch ($$@) { # calls an application hook
     my ($r,$methname, @args) = @_;
     my $methfunc = $r->{S}{$methname};
     return $methfunc->($r->{Cgi}, $r, @args);
 }
 
-sub record_login ($$) {
-    my ($r,$nusername) = @_;
-    my $rsp = $r->{S}{random_source};
-    my $rsf = new IO::File $rsp, '<' or die "$rsp $!";
-    my $bytes = ($r->{S}{associdlen} + 7) >> 3;
-    my $nassocbin;
-    $!=0;
-    read($rsf,$nassocbin,$bytes) == $bytes or die "$rsp $!";
-    close $rsf;
-    my $nassoc = unpack "H*", $nassocbin;
-    my $dbh = $r->{Dbh};
-    $dbh->do("INSERT INTO $r->{S}{assocdb_table}".
-	     " (associd, username, last) VALUES (?,?,?)", {},
-	     $nassoc, $nusername, time);
-    $dbh->do("COMMIT");
-    $r->{U} = $nusername;
-    $r->{A} = $nassoc;
+sub _rp ($$@) {
+    my ($r,$pnvb) = @_;
+    my $pn = $r->{S}{"${pnvb}_param_name"};
+    my $p = $r->_ch('get_param',$pn)
 }
 
-sub _check ($) {
+sub _check_core ($) {
     my ($r) = @_;
-    my $qassoc = $r->_cm('get_param');
+    my $qassoc = $r->_ch('get_param');
     my ($nassoc,$nmutate);
     if (!defined $r->{S}{cookie_name}) {
 	# authentication is by hidden form parameter only
@@ -149,17 +149,135 @@ sub _check ($) {
 	# 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');
+	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->_cm('get_method') eq 'GET';
+	    return undef unless $r->_ch('get_method') eq 'GET';
 	    $nmutate = 0;
 	}
     }
+
+UP TO HERE
+
+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;
+    $!=0;
+    read($rsf,$nassocbin,$bytes) == $bytes or die "$rsp $!";
+    close $rsf;
+    my $nassoc = unpack "H*", $nassocbin;
+    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;
+}
+
+# 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 par 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
+    #
+    #  -   n   POST       i   complain about stale login form
+    #                           show new login form
+    #
+    #  x1  x2  POST       i   login (or switch user)
+    #                           revoke x1 if it was valid and !=x2
+    #                           upgrade x2 to y2 in our db (setting username)
+    #                           set cookie to x2
+    #                           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
+
     my $dbh = $r->{Dbh};
     my ($nusername, $nlast) =
 	$dbh->selectrow_array("SELECT username, last".
@@ -173,24 +291,18 @@ sub _check ($) {
     return ($nusername, $nassoc, $nmutate);
 }
 
-sub check ($) {
+sub _check ($) {
     my ($r) = @_;
 
-    my ($nusername, $nassoc, $nmutate) = $r->_check() or return undef;
+    return if exists $r->{Username};
+    ($r->{Username}, $r->{Assoc}, $r->{Mutate}) = $r->_check();
 
-    $dbh->do("UPDATE $r->{S}{assocdb_table}".
-	     " SET last = ?".
-	     " WHERE associd = ?", {}, time, $nassoc);
-    $dbh->do("COMMIT");
-
-    $r->{Username} = $nusername;
-    $r->{Assoc} = $nassoc;
-    $r->{Mutate} = $nmutate;
-    return $nusername;
-}
-
-sub check_mutate ($) {
-    my ($r) = @_;
+    if (defined $r->{Assoc}) {
+	$dbh->do("UPDATE $r->{S}{assocdb_table}".
+		 " SET last = ?".
+		 " WHERE associd = ?", {}, time, $nassoc);
+	$dbh->do("COMMIT");
+    }
 }
 
 sub logout ($) {
@@ -204,28 +316,79 @@ sub logout ($) {
     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 hiddenv ($) {
+sub hidden_val ($) {
     my ($r) = @_;
-    return defined $r->{A} ? $r->{A} : '';
+    $r->check();
+    return defined $r->{Assoc} ? $r->{Assoc} : '';
 }
 
-sub hiddena ($) {
+#---------- simple wrappers ----------
+
+sub hidden_hargs ($) {
     my ($r) = @_;
-    return (-name => $r->{param_name},
-	    -default => $r->hiddenv());
+    return (-name => $r->{S}{param_name},
+	    -default => $r->hidden_val());
 }
 
-sub hiddenh ($) {
+sub hidden_html ($) {
     my ($r) = @_;
-    return hidden($r->hiddena());
+    return hidden($r->hidden_hargs());
 }
 
-sub cookieac ($) {
+sub cookiea_cargs ($) {
     my ($r) = @_;
-    return (-name => $r->{cookie_name},
-	    -value => hiddenv());
-	    
+    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.
+     }
+ }
+