It depends on the Perl `Locale::Po4a::Po` library (`apt-get install po4a`).
+[[!toc]]
+
Introduction
============
language is a "slave" one.
A page written in the "master" language is a "master" page. It can be
-of any page type supported by ikiwiki, but PO. It does not have to be
+of any page type supported by ikiwiki, except `po`. It does not have to be
named a special way: migration to this plugin does not imply any page
renaming work.
`bla/page/index.en.html`, else as `bla/page.en.html`.
Any translation of a "master" page into a "slave" language is called
-a "slave" page; it is written in the gettext PO format. PO is now
+a "slave" page; it is written in the gettext PO format. `po` is now
a page type supported by ikiwiki.
Example: `bla/page.fr.po` is the PO "message catalog" used to
translatable. It is a [[ikiwiki/PageSpec]], so you have lots of
control over what kind of pages are translatable.
-The PO translations files are anyway not considered as being
-translatable, so you don't need to worry about excluding them
-explicitly from this [[ikiwiki/PageSpec]].
+The `.po` files are not considered as being translatable, so you don't need to
+worry about excluding them explicitly from this [[ikiwiki/PageSpec]].
Internal links
--------------
This plugin enhances the regular [[ikiwiki/PageSpec]] syntax with some
additional tests that are documented [[here|ikiwiki/pagespec/po]].
-Automatic PO files update
--------------------------
+Automatic PO file update
+------------------------
Committing changes to a "master" page:
-1. updates the POT file and the PO files for the supported languages
- (this is done in the `needsbuild` hook); the updated PO files are
- then put under version control
-2. triggers a refresh of the corresponding HTML slave pages (this is
- achieved by making any "slave" page dependent on the corresponding
- "master" page, in the `needsbuild` hook)
+1. updates the POT file and the PO files for the "slave" languages;
+ the updated PO files are then put under version control;
+2. triggers a refresh of the corresponding HTML slave pages.
Also, when the plugin has just been enabled, or when a page has just
been declared as being translatable, the needed POT and PO files are
created, and the PO files are checked into version control.
-TODO
-====
+Discussion pages
+----------------
+
+Discussion should happen in the language in which the pages are
+written for real, *i.e.* the "master" one. If discussion pages are
+enabled, "slave" pages therefore link to the "master" page's
+discussion page.
-OTHERLANGUAGES dependencies
----------------------------
+Translating
+-----------
-Pages using `OTHERLANGUAGES` depend on any "master" and "slave" pages
-whose status is being displayed. It is supposed to trigger dependency
-loops, but no practical bugs were noticed yet.
+One can edit the PO files using ikiwiki's CGI (a message-by-message
+interface could also be implemented at some point).
-Should pages using the `OTHERLANGUAGES` template loop be declared as
-linking to the same page in other versions? To be rigorous, they
-should, but this may clutter the backlinks.
+If [[tips/untrusted_git_push]] is setup, one can edit the PO files in one's
+preferred `$EDITOR`, without needing to be online.
+
+TODO
+====
Security checks
---------------
-- `refreshpofiles` uses `system()`, whose args have to be checked more
- thoroughly to prevent any security issue (command injection, etc.).
-- `refreshpofiles` and `refreshpot` create new files; this may need
- some checks, e.g. using `IkiWiki::prep_writefile()`
+### Security history
+
+The only past security issues I could find in GNU gettext and po4a
+are:
+
+- [CVE-2004-0966](http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2004-0966),
+ *i.e.* [Debian bug #278283](http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=278283):
+ the autopoint and gettextize scripts in the GNU gettext package
+ 1.14 and later versions, as used in Trustix Secure Linux 1.5
+ through 2.1 and other operating systems, allows local users to
+ overwrite files via a symlink attack on temporary files.
+- [CVE-2007-4462](http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2007-4462):
+ `lib/Locale/Po4a/Po.pm` in po4a before 0.32 allows local users to
+ overwrite arbitrary files via a symlink attack on the
+ gettextization.failed.po temporary file.
+
+**FIXME**: check whether this plugin would have been a possible attack
+vector to exploit these vulnerabilities.
+
+Depending on my mood, the lack of found security issues can either
+indicate that there are none, or reveal that no-one ever bothered to
+find (and publish) them.
+
+### PO file features
+
+Can any sort of directives be put in po files that will cause mischief
+(ie, include other files, run commands, crash gettext, whatever)?
+
+> No [documented](http://www.gnu.org/software/gettext/manual/gettext.html#PO-Files)
+> directive is supposed to do so.
+
+### Running po4a on untrusted content
+
+Are there any security issues on running po4a on untrusted content?
+
+> To say the least, this issue is not well covered, at least publicly:
+>
+> - the documentation does not talk about it;
+> - grep'ing the source code for `security` or `trust` gives no answer.
+>
+> I'll ask their opinion to the po4a maintainers.
+>
+> I'm not in a position to audit the code, but I had a look anyway:
+>
+> - no use of `system()`, `exec()` or backticks in `Locale::Po4a`; are
+> there any other way to run external programs in Perl?
+> - a symlink attack vulnerability was already discovered, so I "hope"
+> the code has been checked to find some more already
+> - the po4a parts we are using themselves use the following Perl
+> modules: `DynaLoader`, `Encode`, `Encode::Guess`,
+> `Text::WrapI18N`, `Locale::gettext` (`bindtextdomain`,
+> `textdomain`, `gettext`, `dgettext`)
+>
+> --[[intrigeri]]
+
+### Fuzzing input
+
+I was not able to find any public information about gettext or po4a
+having been tested with a fuzzing program, such as `zzuf` or `fusil`.
+Moreover, some gettext parsers seem to be quite
+[easy to crash](http://fusil.hachoir.org/trac/browser/trunk/fuzzers/fusil-gettext),
+so it might be useful to bang gettext/po4a's heads against such
+a program in order to easily detect some of the most obvious DoS.
+[[--intrigeri]]
gettext/po4a rough corners
--------------------------
-- fix the duplicated PO header mysterious bug
-- fix the "duplicate message definition" error when updating a PO
- file; do PO files need normalizing? (may be a side effect of
- previous bug)
- fix infinite loop when synchronizing two ikiwiki (when checkouts
live in different directories): say bla.fr.po has been updated in
repo2; pulling repo2 from repo1 seems to trigger a PO update, that
changes bla.fr.po in repo1; then pushing repo1 to repo2 triggers
- a PO update, that changes bla.fr.po in repo2; etc.; fixed in
- `629968fc89bced6727981c0a1138072631751fee` ?
+ a PO update, that changes bla.fr.po in repo2; etc.; quickly fixed in
+ `629968fc89bced6727981c0a1138072631751fee`, by disabling references
+ in Pot files. Using `Locale::Po4a::write_if_needed` might be
+ a cleaner solution.
+- new translations created in the web interface must get proper
+ charset/encoding gettext metadata, else the next automatic PO update
+ removes any non-ascii chars; possible solution: put such metadata
+ into the Pot file, and let it propagate; should be fixed in
+ `773de05a7a1ee68d2bed173367cf5e716884945a`, time will tell.
Misc. improvements
------------------
-### automatic POT/PO update
-
-Use the `change` hook instead of `needsbuild`?
-
### page titles
-Use nice page titles from meta plugin in links, as inline already does.
+Use nice page titles from meta plugin in links, as inline already
+does. This is actually a duplicate for
+[[bugs/pagetitle_function_does_not_respect_meta_titles]], which might
+be fixed by something like [[todo/using_meta_titles_for_parentlinks]].
-### websetup
+### source files format
-Which configuration settings are safe enough for websetup?
+Markdown is supported, great, but what about others? The set of file
+formats supported both in ikiwiki and po4a probably is greater than
+`{markdown}`.
Translation quality assurance
-----------------------------
Note: committing to the underlying repository is a way to bypass
this check.
-
-Translating online
-------------------
-
-As PO is a wiki page type, we already have an online PO editor, that
-is ikiwiki's CGI.
-
-**FIXME** preview does not work for PO files.
-
-A message-by-message interface could also be implemented at some
-point; a nice way to do offline translation work (without VCS access)
-still has to be offered, though.
-
-Translating offline without VCS access
---------------------------------------
-
-The following workflow should be made possible for translators without
-VCS access who need to edit the PO files in another editor than a web
-browser:
-
-- download the page's PO file
-- use any PO editor to update the translation
-- upload the updated PO file
-
-Implementation note: a generic mechanism to upload a page's source is
-needed: it's only an alternative way to allow saving a the modified
-page's source with the CGI.
-
-### Short-term workflow
-
-A possible workaround is:
-
-- pretend to edit the PO file online
-- copy the PO file content from the textarea
-- cancel the edit
-- paste the content into a local file.
-- edit the local file in any PO editor
-- pretend to edit the PO file online
-- paste the modified local file's content into the edit textarea
-- save
sipb-www / ikiwiki.git / blobdiff