* Fix a security hole that allowed a web user to edit images and other
[ikiwiki.git] / IkiWiki / CGI.pm
1 #!/usr/bin/perl
2
3 use warnings;
4 use strict;
5 use IkiWiki;
6 use IkiWiki::UserInfo;
7 use open qw{:utf8 :std};
8 use Encode;
9
10 package IkiWiki;
11
12 sub printheader ($) { #{{{
13         my $session=shift;
14         
15         if ($config{sslcookie}) {
16                 print $session->header(-charset => 'utf-8',
17                         -cookie => $session->cookie(-secure => 1));
18         } else {
19                 print $session->header(-charset => 'utf-8');
20         }
21
22 } #}}}
23
24 sub redirect ($$) { #{{{
25         my $q=shift;
26         my $url=shift;
27         if (! $config{w3mmode}) {
28                 print $q->redirect($url);
29         }
30         else {
31                 print "Content-type: text/plain\n";
32                 print "W3m-control: GOTO $url\n\n";
33         }
34 } #}}}
35
36 sub check_canedit ($$$;$) { #{{{
37         my $page=shift;
38         my $q=shift;
39         my $session=shift;
40         my $nonfatal=shift;
41         
42         my $canedit;
43         run_hooks(canedit => sub {
44                 return if defined $canedit;
45                 my $ret=shift->($page, $q, $session);
46                 if (defined $ret && $ret eq "") {
47                         $canedit=1;
48                 }
49                 elsif (defined $ret) {
50                         $canedit=0;
51                         error($ret) unless $nonfatal;
52                 }
53         });
54         return $canedit;
55 } #}}}
56
57 sub decode_form_utf8 ($) { #{{{
58         my $form = shift;
59         foreach my $f ($form->field) {
60                 next if Encode::is_utf8(scalar $form->field($f));
61                 $form->field(name  => $f,
62                              value => decode_utf8($form->field($f)),
63                              force => 1,
64                             );
65         }
66 } #}}}
67
68 sub cgi_recentchanges ($) { #{{{
69         my $q=shift;
70         
71         # Optimisation: building recentchanges means calculating lots of
72         # links. Memoizing htmllink speeds it up a lot (can't be memoized
73         # during page builds as the return values may change, but they
74         # won't here.)
75         eval q{use Memoize};
76         error($@) if $@;
77         memoize("htmllink");
78
79         eval q{use Time::Duration};
80         error($@) if $@;
81
82         my $changelog=[rcs_recentchanges(100)];
83         foreach my $change (@$changelog) {
84                 $change->{when} = concise(ago($change->{when}));
85
86                 $change->{user} = userlink($change->{user});
87
88                 my $is_excess = exists $change->{pages}[10]; # limit pages to first 10
89                 delete @{$change->{pages}}[10 .. @{$change->{pages}}] if $is_excess;
90                 $change->{pages} = [
91                         map {
92                                 $_->{link} = htmllink("", "", $_->{page}, 1, 0, pagetitle($_->{page}));
93                                 $_;
94                         } @{$change->{pages}}
95                 ];
96                 push @{$change->{pages}}, { link => '...' } if $is_excess;
97         }
98
99         my $template=template("recentchanges.tmpl"); 
100         $template->param(
101                 title => "RecentChanges",
102                 indexlink => indexlink(),
103                 wikiname => $config{wikiname},
104                 changelog => $changelog,
105                 baseurl => baseurl(),
106         );
107         run_hooks(pagetemplate => sub {
108                 shift->(page => "", destpage => "", template => $template);
109         });
110         print $q->header(-charset => 'utf-8'), $template->output;
111 } #}}}
112
113 # Check if the user is signed in. If not, redirect to the signin form and
114 # save their place to return to later.
115 sub needsignin ($$) { #{{{
116         my $q=shift;
117         my $session=shift;
118
119         if (! defined $session->param("name") ||
120             ! userinfo_get($session->param("name"), "regdate")) {
121                 if (! defined $session->param("postsignin")) {
122                         $session->param(postsignin => $ENV{QUERY_STRING});
123                 }
124                 cgi_signin($q, $session);
125                 cgi_savesession($session);
126                 exit;
127         }
128 } #}}}  
129
130 sub cgi_signin ($$) { #{{{
131         my $q=shift;
132         my $session=shift;
133
134         eval q{use CGI::FormBuilder};
135         error($@) if $@;
136         my $form = CGI::FormBuilder->new(
137                 title => "signin",
138                 header => 1,
139                 charset => "utf-8",
140                 method => 'POST',
141                 required => 'NONE',
142                 javascript => 0,
143                 params => $q,
144                 action => $config{cgiurl},
145                 header => 0,
146                 template => scalar template_params("signin.tmpl"),
147                 stylesheet => baseurl()."style.css",
148         );
149         my $buttons=["Login"];
150         
151         if ($q->param("do") ne "signin" && !$form->submitted) {
152                 $form->text(gettext("You need to log in first."));
153         }
154         $form->field(name => "do", type => "hidden", value => "signin",
155                 force => 1);
156         
157         run_hooks(formbuilder_setup => sub {
158                 shift->(form => $form, cgi => $q, session => $session);
159         });
160         
161         decode_form_utf8($form);
162
163         if (exists $hooks{formbuilder}) {
164                 run_hooks(formbuilder => sub {
165                         shift->(form => $form, cgi => $q, session => $session,
166                                 buttons => $buttons);
167                 });
168         }
169         else {
170                 if ($form->submitted) {
171                         $form->validate;
172                 }
173                 printheader($session);
174                 print misctemplate($form->title, $form->render(submit => $buttons));
175         }
176 } #}}}
177
178 sub cgi_postsignin ($$) { #{{{
179         my $q=shift;
180         my $session=shift;
181
182         # Continue with whatever was being done before the signin process.
183         my $postsignin=CGI->new($session->param("postsignin"));
184         $session->clear("postsignin");
185         cgi($postsignin, $session);
186         cgi_savesession($session);
187         exit;
188 } #}}}
189
190 sub cgi_prefs ($$) { #{{{
191         my $q=shift;
192         my $session=shift;
193
194         needsignin($q, $session);
195
196         eval q{use CGI::FormBuilder};
197         error($@) if $@;
198         my $form = CGI::FormBuilder->new(
199                 title => "preferences",
200                 header => 0,
201                 charset => "utf-8",
202                 method => 'POST',
203                 validate => {
204                         email => 'EMAIL',
205                 },
206                 required => 'NONE',
207                 javascript => 0,
208                 params => $q,
209                 action => $config{cgiurl},
210                 template => scalar template_params("prefs.tmpl"),
211                 stylesheet => baseurl()."style.css",
212         );
213         my $buttons=["Save Preferences", "Logout", "Cancel"];
214
215         run_hooks(formbuilder_setup => sub {
216                 shift->(form => $form, cgi => $q, session => $session);
217         });
218         
219         $form->field(name => "do", type => "hidden");
220         $form->field(name => "email", size => 50);
221         $form->field(name => "subscriptions", size => 50,
222                 comment => "(".htmllink("", "", "PageSpec", 1).")");
223         $form->field(name => "banned_users", size => 50);
224         
225         my $user_name=$session->param("name");
226         if (! is_admin($user_name)) {
227                 $form->field(name => "banned_users", type => "hidden");
228         }
229
230         if (! $form->submitted) {
231                 $form->field(name => "email", force => 1,
232                         value => userinfo_get($user_name, "email"));
233                 $form->field(name => "subscriptions", force => 1,
234                         value => userinfo_get($user_name, "subscriptions"));
235                 if (is_admin($user_name)) {
236                         $form->field(name => "banned_users", force => 1,
237                                 value => join(" ", get_banned_users()));
238                 }
239         }
240         
241         decode_form_utf8($form);
242         
243         if ($form->submitted eq 'Logout') {
244                 $session->delete();
245                 redirect($q, $config{url});
246                 return;
247         }
248         elsif ($form->submitted eq 'Cancel') {
249                 redirect($q, $config{url});
250                 return;
251         }
252         elsif ($form->submitted eq 'Save Preferences' && $form->validate) {
253                 foreach my $field (qw(email subscriptions)) {
254                         if (defined $form->field($field) && length $form->field($field)) {
255                                 userinfo_set($user_name, $field, $form->field($field)) || error("failed to set $field");
256                         }
257                 }
258                 if (is_admin($user_name)) {
259                         set_banned_users(grep { ! is_admin($_) }
260                                         split(' ', $form->field("banned_users")));
261                 }
262                 $form->text(gettext("Preferences saved."));
263         }
264         
265         if (exists $hooks{formbuilder}) {
266                 run_hooks(formbuilder => sub {
267                         shift->(form => $form, cgi => $q, session => $session,
268                                 buttons => $buttons);
269                 });
270         }
271         else {
272                 printheader($session);
273                 print misctemplate($form->title, $form->render(submit => $buttons));
274         }
275 } #}}}
276
277 sub cgi_editpage ($$) { #{{{
278         my $q=shift;
279         my $session=shift;
280
281         my @fields=qw(do rcsinfo subpage from page type editcontent comments);
282         my @buttons=("Save Page", "Preview", "Cancel");
283         
284         eval q{use CGI::FormBuilder};
285         error($@) if $@;
286         my $form = CGI::FormBuilder->new(
287                 fields => \@fields,
288                 header => 1,
289                 charset => "utf-8",
290                 method => 'POST',
291                 validate => {
292                         editcontent => '/.+/',
293                 },
294                 required => [qw{editcontent}],
295                 javascript => 0,
296                 params => $q,
297                 action => $config{cgiurl},
298                 table => 0,
299                 template => scalar template_params("editpage.tmpl"),
300         );
301         
302         run_hooks(formbuilder_setup => sub {
303                 shift->(form => $form, cgi => $q, session => $session);
304         });
305         
306         decode_form_utf8($form);
307         
308         # This untaint is safe because titlepage removes any problematic
309         # characters.
310         my ($page)=$form->field('page');
311         $page=titlepage(possibly_foolish_untaint($page));
312         if (! defined $page || ! length $page || file_pruned($page, $config{srcdir}) || $page=~/^\//) {
313                 error("bad page name");
314         }
315         
316         my $from;
317         if (defined $form->field('from')) {
318                 ($from)=$form->field('from')=~/$config{wiki_file_regexp}/;
319         }
320         
321         my $file;
322         my $type;
323         if (exists $pagesources{$page}) {
324                 $file=$pagesources{$page};
325                 $type=pagetype($file);
326                 if (! defined $type) {
327                         error(sprintf(gettext("%s is not an editable page"), $page));
328                 }
329         }
330         else {
331                 $type=$form->param('type');
332                 if (defined $type && length $type && $hooks{htmlize}{$type}) {
333                         $type=possibly_foolish_untaint($type);
334                 }
335                 elsif (defined $from) {
336                         # favor the type of linking page
337                         $type=pagetype($pagesources{$from});
338                 }
339                 $type=$config{default_pageext} unless defined $type;
340                 $file=$page.".".$type;
341         }
342
343         my $newfile=0;
344         if (! -e "$config{srcdir}/$file") {
345                 $newfile=1;
346         }
347
348         $form->field(name => "do", type => 'hidden');
349         $form->field(name => "from", type => 'hidden');
350         $form->field(name => "rcsinfo", type => 'hidden');
351         $form->field(name => "subpage", type => 'hidden');
352         $form->field(name => "page", value => $page, force => 1);
353         $form->field(name => "type", value => $type, force => 1);
354         $form->field(name => "comments", type => "text", size => 80);
355         $form->field(name => "editcontent", type => "textarea", rows => 20,
356                 cols => 80);
357         $form->tmpl_param("can_commit", $config{rcs});
358         $form->tmpl_param("indexlink", indexlink());
359         $form->tmpl_param("helponformattinglink",
360                 htmllink("", "", "HelpOnFormatting", 1));
361         $form->tmpl_param("baseurl", baseurl());
362         if (! $form->submitted) {
363                 $form->field(name => "rcsinfo", value => rcs_prepedit($file),
364                         force => 1);
365         }
366         
367         if ($form->submitted eq "Cancel") {
368                 if ($newfile && defined $from) {
369                         redirect($q, "$config{url}/".htmlpage($from));
370                 }
371                 elsif ($newfile) {
372                         redirect($q, $config{url});
373                 }
374                 else {
375                         redirect($q, "$config{url}/".htmlpage($page));
376                 }
377                 return;
378         }
379         elsif ($form->submitted eq "Preview") {
380                 my $content=$form->field('editcontent');
381                 my $comments=$form->field('comments');
382                 $form->field(name => "editcontent",
383                                 value => $content, force => 1);
384                 $form->field(name => "comments",
385                                 value => $comments, force => 1);
386                 $config{rss}=$config{atom}=0; # avoid preview writing a feed!
387                 $form->tmpl_param("page_preview",
388                         htmlize($page, $type,
389                         linkify($page, "",
390                         preprocess($page, $page,
391                         filter($page, $content)))));
392         }
393         else {
394                 $form->tmpl_param("page_preview", "");
395         }
396         $form->tmpl_param("page_conflict", "");
397         
398         if (! $form->submitted || $form->submitted eq "Preview" || 
399             ! $form->validate) {
400                 if ($form->field("do") eq "create") {
401                         my @page_locs;
402                         my $best_loc;
403                         if (! defined $from || ! length $from ||
404                             $from ne $form->field('from') ||
405                             file_pruned($from, $config{srcdir}) ||
406                             $from=~/^\// ||
407                             $form->submitted eq "Preview") {
408                                 @page_locs=$best_loc=$page;
409                         }
410                         else {
411                                 my $dir=$from."/";
412                                 $dir=~s![^/]+/+$!!;
413                                 
414                                 if ((defined $form->field('subpage') && length $form->field('subpage')) ||
415                                     $page eq gettext('discussion')) {
416                                         $best_loc="$from/$page";
417                                 }
418                                 else {
419                                         $best_loc=$dir.$page;
420                                 }
421                                 
422                                 push @page_locs, $dir.$page;
423                                 push @page_locs, "$from/$page";
424                                 while (length $dir) {
425                                         $dir=~s![^/]+/+$!!;
426                                         push @page_locs, $dir.$page;
427                                 }
428                         }
429                         push @page_locs, "$config{userdir}/$page"
430                                 if length $config{userdir};
431
432                         @page_locs = grep {
433                                 ! exists $pagecase{lc $_}
434                         } @page_locs;
435                         if (! @page_locs) {
436                                 # hmm, someone else made the page in the
437                                 # meantime?
438                                 redirect($q, "$config{url}/".htmlpage($page));
439                                 return;
440                         }
441
442                         my @editable_locs = grep {
443                                 check_canedit($_, $q, $session, 1)
444                         } @page_locs;
445                         if (! @editable_locs) {
446                                 # let it throw an error this time
447                                 map { check_canedit($_, $q, $session) } @page_locs;
448                         }
449                         
450                         my @page_types;
451                         if (exists $hooks{htmlize}) {
452                                 @page_types=keys %{$hooks{htmlize}};
453                         }
454                         
455                         $form->tmpl_param("page_select", 1);
456                         $form->field(name => "page", type => 'select',
457                                 options => \@editable_locs, value => $best_loc);
458                         $form->field(name => "type", type => 'select',
459                                 options => \@page_types);
460                         $form->title(sprintf(gettext("creating %s"), pagetitle($page)));
461                 }
462                 elsif ($form->field("do") eq "edit") {
463                         check_canedit($page, $q, $session);
464                         if (! defined $form->field('editcontent') || 
465                             ! length $form->field('editcontent')) {
466                                 my $content="";
467                                 if (exists $pagesources{$page}) {
468                                         $content=readfile(srcfile($pagesources{$page}));
469                                         $content=~s/\n/\r\n/g;
470                                 }
471                                 $form->field(name => "editcontent", value => $content,
472                                         force => 1);
473                         }
474                         $form->tmpl_param("page_select", 0);
475                         $form->field(name => "page", type => 'hidden');
476                         $form->field(name => "type", type => 'hidden');
477                         $form->title(sprintf(gettext("editing %s"), pagetitle($page)));
478                 }
479                 
480                 print $form->render(submit => \@buttons);
481         }
482         else {
483                 # save page
484                 check_canedit($page, $q, $session);
485                 
486                 my $content=$form->field('editcontent');
487
488                 $content=~s/\r\n/\n/g;
489                 $content=~s/\r/\n/g;
490                 writefile($file, $config{srcdir}, $content);
491                 
492                 if ($config{rcs}) {
493                         my $message="";
494                         if (defined $form->field('comments') &&
495                             length $form->field('comments')) {
496                                 $message=$form->field('comments');
497                         }
498                         
499                         if ($newfile) {
500                                 rcs_add($file);
501                         }
502                         # prevent deadlock with post-commit hook
503                         unlockwiki();
504                         # presumably the commit will trigger an update
505                         # of the wiki
506                         my $conflict=rcs_commit($file, $message,
507                                 $form->field("rcsinfo"),
508                                 $session->param("name"), $ENV{REMOTE_ADDR});
509                 
510                         if (defined $conflict) {
511                                 $form->field(name => "rcsinfo", value => rcs_prepedit($file),
512                                         force => 1);
513                                 $form->tmpl_param("page_conflict", 1);
514                                 $form->field("editcontent", value => $conflict, force => 1);
515                                 $form->field(name => "comments", value => $form->field('comments'), force => 1);
516                                 $form->field("do", "edit)");
517                                 $form->tmpl_param("page_select", 0);
518                                 $form->field(name => "page", type => 'hidden');
519                                 $form->field(name => "type", type => 'hidden');
520                                 $form->title(sprintf(gettext("editing %s"), $page));
521                                 print $form->render(submit => \@buttons);
522                                 return;
523                         }
524                         else {
525                                 # Make sure that the repo is up-to-date;
526                                 # locking prevents the post-commit hook
527                                 # from updating it.
528                                 rcs_update();
529                         }
530                 }
531                 else {
532                         require IkiWiki::Render;
533                         refresh();
534                         saveindex();
535                 }
536                 
537                 # The trailing question mark tries to avoid broken
538                 # caches and get the most recent version of the page.
539                 redirect($q, "$config{url}/".htmlpage($page)."?updated");
540         }
541 } #}}}
542
543 sub cgi_getsession ($) { #{{{
544         my $q=shift;
545
546         eval q{use CGI::Session};
547         CGI::Session->name("ikiwiki_session_".encode_utf8($config{wikiname}));
548         
549         my $oldmask=umask(077);
550         my $session = CGI::Session->new("driver:DB_File", $q,
551                 { FileName => "$config{wikistatedir}/sessions.db" });
552         umask($oldmask);
553
554         return $session;
555 } #}}}
556
557 sub cgi_savesession ($) { #{{{
558         my $session=shift;
559
560         # Force session flush with safe umask.
561         my $oldmask=umask(077);
562         $session->flush;
563         umask($oldmask);
564 } #}}}
565
566 sub cgi (;$$) { #{{{
567         my $q=shift;
568         my $session=shift;
569
570         if (! $q) {
571                 eval q{use CGI};
572                 error($@) if $@;
573         
574                 $q=CGI->new;
575         
576                 run_hooks(cgi => sub { shift->($q) });
577         }
578
579         my $do=$q->param('do');
580         if (! defined $do || ! length $do) {
581                 my $error = $q->cgi_error;
582                 if ($error) {
583                         error("Request not processed: $error");
584                 }
585                 else {
586                         error("\"do\" parameter missing");
587                 }
588         }
589         
590         # Things that do not need a session.
591         if ($do eq 'recentchanges') {
592                 cgi_recentchanges($q);
593                 return;
594         }
595         elsif ($do eq 'hyperestraier') {
596                 cgi_hyperestraier();
597         }
598
599         # Need to lock the wiki before getting a session.
600         lockwiki();
601         
602         if (! $session) {
603                 $session=cgi_getsession($q);
604         }
605         
606         # Auth hooks can sign a user in.
607         if ($do ne 'signin' && ! defined $session->param("name")) {
608                 run_hooks(auth => sub {
609                         shift->($q, $session)
610                 });
611                 if (defined $session->param("name")) {
612                         # Make sure whatever user was authed is in the
613                         # userinfo db.
614                         if (! userinfo_get($session->param("name"), "regdate")) {
615                                 userinfo_setall($session->param("name"), {
616                                         email => "",
617                                         password => "",
618                                         regdate => time,
619                                 });
620                         }
621                 }
622         }
623         
624         if (defined $session->param("name") &&
625             userinfo_get($session->param("name"), "banned")) {
626                 print $q->header(-status => "403 Forbidden");
627                 $session->delete();
628                 print gettext("You are banned.");
629                 cgi_savesession($session);
630         }
631         elsif ($do eq 'signin') {
632                 cgi_signin($q, $session);
633                 cgi_savesession($session);
634         }
635         elsif (defined $session->param("postsignin")) {
636                 cgi_postsignin($q, $session);
637         }
638         elsif ($do eq 'prefs') {
639                 cgi_prefs($q, $session);
640         }
641         elsif ($do eq 'create' || $do eq 'edit') {
642                 cgi_editpage($q, $session);
643         }
644         elsif ($do eq 'blog') {
645                 my $page=titlepage(decode_utf8($q->param('title')));
646                 $page=~s/(\/)/"__".ord($1)."__"/eg; # escape slashes too
647                 # if the page already exists, munge it to be unique
648                 my $from=$q->param('from');
649                 my $add="";
650                 while (exists $pagecase{lc "$from/$page$add"}) {
651                         $add=1 unless length $add;
652                         $add++;
653                 }
654                 $q->param('page', $page.$add);
655                 # now run same as create
656                 $q->param('do', 'create');
657                 cgi_editpage($q, $session);
658         }
659         elsif ($do eq 'postsignin') {
660                 error(gettext("login failed, perhaps you need to turn on cookies?"));
661         }
662         else {
663                 error("unknown do parameter");
664         }
665 } #}}}
666
667 sub userlink ($) { #{{{
668         my $user=shift;
669
670         eval q{use CGI 'escapeHTML'};
671         error($@) if $@;
672         if ($user =~ m!^https?://! &&
673             eval q{use Net::OpenID::VerifiedIdentity; 1} && !$@) {
674                 # Munge user-urls, as used by eg, OpenID.
675                 my $oid=Net::OpenID::VerifiedIdentity->new(identity => $user);
676                 my $display=$oid->display;
677                 # Convert "user.somehost.com" to "user [somehost.com]".
678                 if ($display !~ /\[/) {
679                         $display=~s/^(.*?)\.([^.]+\.[a-z]+)$/$1 [$2]/;
680                 }
681                 # Convert "http://somehost.com/user" to "user [somehost.com]".
682                 if ($display !~ /\[/) {
683                         $display=~s/^https?:\/\/(.+)\/([^\/]+)$/$2 [$1]/;
684                 }
685                 $display=~s!^https?://!!; # make sure this is removed
686                 return "<a href=\"$user\">".escapeHTML($display)."</a>";
687         }
688         else {
689                 return htmllink("", "", escapeHTML(
690                         length $config{userdir} ? $config{userdir}."/".$user : $user
691                 ), 1);
692         }
693 } #}}}
694
695 1