X-Git-Url: http://git.vanrenterghem.biz/git.ikiwiki.info.git/blobdiff_plain/86edd539f4995b49e57086e055b0c9a5571b2ff3..22961f81ddf642b24e45fdf9707dff06e17742a7:/doc/plugins/po.mdwn?ds=sidebyside
diff --git a/doc/plugins/po.mdwn b/doc/plugins/po.mdwn
index 6c0d49197..b7c1582ca 100644
--- a/doc/plugins/po.mdwn
+++ b/doc/plugins/po.mdwn
@@ -5,8 +5,10 @@ This plugin adds support for multi-lingual wikis, translated with
gettext, using [po4a](http://po4a.alioth.debian.org/).
It depends on the Perl `Locale::Po4a::Po` library (`apt-get install po4a`).
+As detailed bellow in the security section, `po4a` is subject to
+denial-of-service attacks before version 0.35.
-[[!toc]]
+[[!toc levels=2]]
Introduction
============
@@ -31,6 +33,12 @@ Example: `bla/page.fr.po` is the PO "message catalog" used to
translate `bla/page.mdwn` into French; if `usedirs` is enabled, it is
rendered as `bla/page/index.fr.html`, else as `bla/page.fr.html`
+(In)Compatibility
+=================
+
+This plugin does not support the `indexpages` mode. If you don't know
+what it is, you probably don't care.
+
Configuration
=============
@@ -41,15 +49,15 @@ Supported languages
`po_master_language` is used to set the "master" language in
`ikiwiki.setup`, such as:
- po_master_language => { 'code' => 'en', 'name' => 'English' }
+ po_master_language: en|English
`po_slave_languages` is used to set the list of supported "slave"
languages, such as:
- po_slave_languages => { 'fr' => 'Français',
- 'es' => 'Castellano',
- 'de' => 'Deutsch',
- }
+ po_slave_languages:
+ - fr|Français
+ - es|Español
+ - de|Deutsch
Decide which pages are translatable
-----------------------------------
@@ -64,39 +72,40 @@ worry about excluding them explicitly from this [[ikiwiki/PageSpec]].
Internal links
--------------
+### Links targets
+
The `po_link_to` option in `ikiwiki.setup` is used to decide how
internal links should be generated, depending on web server features
and site-specific preferences.
-### Default linking behavior
+#### Default linking behavior
If `po_link_to` is unset, or set to `default`, ikiwiki's default
linking behavior is preserved: `\[[destpage]]` links to the master
language's page.
-### Link to current language
+#### Link to current language
If `po_link_to` is set to `current`, `\[[destpage]]` links to the
`destpage`'s version written in the current page's language, if
available, *i.e.*:
-- `foo/destpage/index.LL.html` if `usedirs` is enabled
-- `foo/destpage.LL.html` if `usedirs` is disabled
+* `foo/destpage/index.LL.html` if `usedirs` is enabled
+* `foo/destpage.LL.html` if `usedirs` is disabled
-### Link to negotiated language
+#### Link to negotiated language
If `po_link_to` is set to `negotiated`, `\[[page]]` links to the
negotiated preferred language, *i.e.* `foo/page/`.
(In)compatibility notes:
-- if `usedirs` is disabled, it does not make sense to set `po_link_to`
+* if `usedirs` is disabled, it does not make sense to set `po_link_to`
to `negotiated`; this option combination is neither implemented
nor allowed.
-- if the web server does not support Content Negotiation, setting
+* if the web server does not support Content Negotiation, setting
`po_link_to` to `negotiated` will produce a unusable website.
-
Server support
==============
@@ -105,23 +114,28 @@ Apache
Using Apache `mod_negotiation` makes it really easy to have Apache
serve any page in the client's preferred language, if available.
-This is the default Debian Apache configuration.
-When `usedirs` is enabled, one has to set `DirectoryIndex index` for
-the wiki context.
+Add 'Options MultiViews' to the wiki directory's configuration in Apache.
+
+When `usedirs` is enabled, you should also set `DirectoryIndex index`.
+
+These settings are also recommended, in order to avoid serving up rss files
+as index pages:
+
+ AddType application/rss+xml;qs=0.8 .rss
+ AddType application/atom+xml;qs=0.8 .atom
-Setting `DefaultLanguage LL` (replace `LL` with your default MIME
-language code) for the wiki context can help to ensure
-`bla/page/index.en.html` is served as `Content-Language: LL`.
+For details, see [Apache's documentation](http://httpd.apache.org/docs/2.2/content-negotiation.html).
lighttpd
--------
-lighttpd unfortunately does not support content negotiation.
+Recent versions of lighttpd should be able to use
+`$HTTP["language"]` to configure the translated pages to be served.
-**FIXME**: does `mod_magnet` provide the functionality needed to
- emulate this?
+See [Lighttpd Issue](http://redmine.lighttpd.net/issues/show/1119)
+TODO: Example
Usage
=====
@@ -129,51 +143,36 @@ Usage
Templates
---------
+When `po_link_to` is not set to `negotiated`, one should replace some
+occurrences of `BASEURL` with `HOMEPAGEURL` to get correct links to
+the wiki homepage.
+
The `ISTRANSLATION` and `ISTRANSLATABLE` variables can be used to
display things only on translatable or translation pages.
+The `LANG_CODE` and `LANG_NAME` variables can respectively be used to
+display the current page's language code and pretty name.
+
### Display page's versions in other languages
The `OTHERLANGUAGES` loop provides ways to display other languages'
versions of the same page, and the translations' status.
-One typically adds the following code to `templates/page.tmpl`:
-
-
-
-
-
- -
- ">
-
- ( %)
-
-
-
-
-
-
-
-The following variables are available inside the loop (for every page in):
-
-- `URL` - url to the page
-- `CODE` - two-letters language code
-- `LANGUAGE` - language name (as defined in `po_slave_languages`)
-- `MASTER` - is true (1) if, and only if the page is a "master" page
-- `PERCENT` - for "slave" pages, is set to the translation completeness, in percents
+An example of its use can be found in the default
+`templates/page.tmpl`. In case you want to customize it, the following
+variables are available inside the loop (for every page in):
+
+* `URL` - url to the page
+* `CODE` - two-letters language code
+* `LANGUAGE` - language name (as defined in `po_slave_languages`)
+* `MASTER` - is true (1) if, and only if the page is a "master" page
+* `PERCENT` - for "slave" pages, is set to the translation completeness, in percents
### Display the current translation status
The `PERCENTTRANSLATED` variable is set to the translation
-completeness, expressed in percent, on "slave" pages.
-
-One can use it this way:
-
-
-
-
-
-
+completeness, expressed in percent, on "slave" pages. It is used by
+the default `templates/page.tmpl`.
Additional PageSpec tests
-------------------------
@@ -194,14 +193,18 @@ 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.
-Discussion pages
-----------------
+Discussion pages and other sub-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.
+Likewise, "slave" pages are not supposed to have sub-pages;
+[[WikiLinks|ikiwiki/wikilink]] that appear on a "slave" page therefore link to
+the master page's sub-pages.
+
Translating
-----------
@@ -211,112 +214,47 @@ interface could also be implemented at some point).
If [[tips/untrusted_git_push]] is setup, one can edit the PO files in one's
preferred `$EDITOR`, without needing to be online.
-TODO
-====
+Markup languages support
+------------------------
+
+[[Markdown|mdwn]] and [[html]] are well supported. Some other markup
+languages supported by ikiwiki mostly work, but some pieces of syntax
+are not rendered correctly on the slave pages:
+
+* [[reStructuredText|rst]]: anonymous hyperlinks and internal
+ cross-references
+* [[wikitext]]: conversion of newlines to paragraphs
+* [[creole]]: verbatim text is wrapped, tables are broken
+* LaTeX: not supported yet; the dedicated po4a module
+ could be used to support it, but it would need a security audit
+* other markup languages have not been tested.
-Security checks
+Renaming a page
---------------
-### 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 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.; 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
-------------------
-
-### page titles
-
-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]].
-
-Translation quality assurance
------------------------------
-
-Modifying a PO file via the CGI must be forbidden if the new version
-is not a valid PO file. As a bonus, check that it provides a more
-complete translation than the existing one.
-
-A new `cansave` type of hook would be needed to implement this.
-
-Note: committing to the underlying repository is a way to bypass
-this check.
+A translatable page may be renamed using the web interface and the
+[[rename plugin|plugins/rename]], or using the VCS directly; in
+the latter case, *both* the "master" page and every corresponding
+`.po` file must be renamed in the same commit.
+
+Security
+========
+
+[[po/discussion]] contains a detailed security analysis of this plugin
+and its dependencies.
+
+When using po4a older than 0.35, it is recommended to uninstall
+`Text::WrapI18N` (Debian package `libtext-wrapi18n-perl`), in order to
+avoid a potential denial of service.
+
+BUGS
+====
+
+[[!inline pages="bugs/po:* and !bugs/done and !link(bugs/done) and !bugs/*/*"
+feeds=no actions=no archive=yes show=0]]
+
+TODO
+====
+
+[[!inline pages="todo/po:* and !todo/done and !link(todo/done) and !todo/*/*"
+feeds=no actions=no archive=yes show=0]]