X-Git-Url: http://git.vanrenterghem.biz/git.ikiwiki.info.git/blobdiff_plain/e397888a77b10d96437754779062852f56d96765..523718b181e9767d322bba3fe0b68cfcf85056a6:/doc/plugins/po.mdwn?ds=sidebyside diff --git a/doc/plugins/po.mdwn b/doc/plugins/po.mdwn index 09df26394..92fba349f 100644 --- a/doc/plugins/po.mdwn +++ b/doc/plugins/po.mdwn @@ -31,6 +31,12 @@ 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 ============= @@ -129,6 +135,10 @@ 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. @@ -194,14 +204,18 @@ 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|wikilink]] that appear on a "slave" page therefore link to +the master page's sub-pages. + Translating ----------- @@ -211,6 +225,22 @@ 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. +Markup languages support +------------------------ + +Markdown is 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 +* [[html]] and LaTeX: not supported yet; the dedicated po4a modules + could be used to support them, but they would need a security audit +* other markup languages have not been tested. + + TODO ==== @@ -277,8 +307,6 @@ an initial goal, and analysing in detail the possible issues. read any file. NB: this hack depends on po4a internals to stay the same. -#### To be checked - ##### Locale::Po4a modules The modules we want to use have to be checked, as not all are safe @@ -295,24 +323,21 @@ means the `Text` module only. variables; they seem safe to me, but someone more expert than me will need to check. Joey? + > Freaky code, but seems ok due to use of `quotementa`. + +#### To be checked + ##### Text::WrapI18N `Text::WrapI18N` can cause DoS (see the [Debian bug #470250](http://bugs.debian.org/470250)), but it is optional and we do not need the features it provides. -It is loaded if available by `Locale::Po4a::Common`; looking at the -code, I'm not sure we can prevent this at all, but maybe some symbol -table manipulation tricks could work; overriding -`Locale::Po4a::Common::wrapi18n` may be easier. I'm no expert at all -in this field. Joey? [[--intrigeri]] - -> Update: Nicolas François suggests we add an option to po4a to -> disable it. It would do the trick, but only for people running -> a brand new po4a (probably too late for Lenny). Anyway, this option -> would have to take effect in a `BEGIN` / `eval` that I'm not -> familiar with. I can learn and do it, in case no Perl wizard -> volunteers to provide the po4a patch. [[--intrigeri]] +> I proposed a patch based on Joey's to po4a-devel, allowing to fully +> disable this module's use. When it is merged upstream, we'll need to add +> `use Locale::Po4a::Common qw(nowrapi18n)` to `po.pm`, before loading +> any other `Locale::Po4a` module. A versioned dependency may be needed. +> --[[intrigeri]] ##### Term::ReadKey @@ -321,42 +346,106 @@ works nicely without it. But the po4a Debian package recommends `libterm-readkey-perl`, so it will probably be installed on most systems using the po plugin. -If `$ENV{COLUMNS}` is not set, `Locale::Po4a::Common` uses -`Term::ReadKey::GetTerminalSize()` to get the terminal size. How safe -is this? +`Term::ReadKey` has too far reaching implications for us to +be able to guarantee anything wrt. security. -Part of `Term::ReadKey` is written in C. Depending on the runtime -platform, this function use ioctl, environment, or C library function -calls, and may end up running the `resize` command (without -arguments). +> The option that disables `Text::WrapI18N` also disables +> `Term::ReadKey` as a consequence. [[--intrigeri]] -IMHO, using Term::ReadKey has too far reaching implications for us to -be able to guarantee anything wrt. security. Since it is anyway of no -use in our case, I suggest we define `ENV{COLUMNS}` before loading -`Locale::Po4a::Common`, just to be on the safe side. Joey? -[[--intrigeri]] +### msgmerge -> Update: adding an option to disable `Text::WrapI18N`, as Nicolas -> François suggested, would as a bonus disable `Term::ReadKey` -> as well. [[--intrigeri]] +`refreshpofiles()` runs this external program. -### msgmerge +A po4a developer answered he does "not expect any security issues from +it". I did not manage to crash it with `zzuf`, nor was able to find +any past security holes. + +### msgfmt -`refreshpofiles()` runs this external program. A po4a developer -answered he does "not expect any security issues from it". +`isvalidpo()` runs this external program. + +* I could not manage to make it behave badly using zzuf, it exits + cleanly when too many errors are detected. +* I could not find any past security holes. ### 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 msgmerge/po4a's heads against such -a program in order to easily detect some of the most obvious DoS. -[[--intrigeri]] +Test conditions: + +- a 21M file containing 100 concatenated copies of all the files in my + `/usr/share/common-licenses/`; I had no existing PO file or + translated versions at hand, which renders these tests + quite incomplete. +- po4a was the Debian 0.34-2 package; the same tests were also run + after replacing the `Text` module with the CVS one (the core was not + changed in CVS since 0.34-2 was released), without any significant + difference in the results. +- Perl 5.10.0-16 + +#### po4a-gettextize + +`po4a-gettextize` uses more or less the same po4a features as our +`refreshpot` function. + +Without specifying an input charset, zzuf'ed `po4a-gettextize` quickly +errors out, complaining it was not able to detect the input charset; +it leaves no incomplete file on disk. + +So I had to pretend the input was in UTF-8, as does the po plugin. -> po4a was not fuzzy-tested, but according to one of its developers, -> "it would be really appreciated". [[--intrigeri]] +Two ways of crashing were revealed by this command-line: + + zzuf -vc -s 0:100 -r 0.1:0.5 \ + po4a-gettextize -f text -o markdown -M utf-8 -L utf-8 \ + -m LICENSES >/dev/null + +They are: + + Malformed UTF-8 character (UTF-16 surrogate 0xdcc9) in substitution iterator at /usr/share/perl5/Locale/Po4a/Po.pm line 1443. + Malformed UTF-8 character (fatal) at /usr/share/perl5/Locale/Po4a/Po.pm line 1443. + +and + + Malformed UTF-8 character (UTF-16 surrogate 0xdcec) in substitution (s///) at /usr/share/perl5/Locale/Po4a/Po.pm line 1443. + Malformed UTF-8 character (fatal) at /usr/share/perl5/Locale/Po4a/Po.pm line 1443. + +Perl seems to exit cleanly, and an incomplete PO file is written on +disk. I not sure whether if this is a bug in Perl or in `Po.pm`. + +> It's fairly standard perl behavior when fed malformed utf-8. As long as it doesn't +> crash ikiwiki, it's probably acceptable. Ikiwiki can do some similar things itself when fed malformed utf-8 (doesn't crash tho) --[[Joey]] + +#### po4a-translate + +`po4a-translate` uses more or less the same po4a features as our +`filter` function. + +Without specifying an input charset, same behaviour as +`po4a-gettextize`, so let's specify UTF-8 as input charset as of now. + + zzuf -cv \ + po4a-translate -d -f text -o markdown -M utf-8 -L utf-8 \ + -k 0 -m LICENSES -p LICENSES.fr.po -l test.fr + +... prints tons of occurences of the following error, but a complete +translated document is written (obviously with some weird chars +inside): + + Use of uninitialized value in string ne at /usr/share/perl5/Locale/Po4a/TransTractor.pm line 854. + Use of uninitialized value in string ne at /usr/share/perl5/Locale/Po4a/TransTractor.pm line 840. + Use of uninitialized value in pattern match (m//) at /usr/share/perl5/Locale/Po4a/Po.pm line 1002. + +While: + + zzuf -cv -s 0:10 -r 0.001:0.3 \ + po4a-translate -d -f text -o markdown -M utf-8 -L utf-8 \ + -k 0 -m LICENSES -p LICENSES.fr.po -l test.fr + +... seems to lose the fight, at the `readpo(LICENSES.fr.po)` step, +against some kind of infinite loop, deadlock, or any similar beast. + +The root of this bug lies in `Text::WrapI18N`, see above for +possible solutions. gettext/po4a rough corners -------------------------- @@ -376,31 +465,56 @@ gettext/po4a rough corners into the Pot file, and let it propagate; should be fixed in `773de05a7a1ee68d2bed173367cf5e716884945a`, time will tell. -Misc. improvements ------------------- +Better links +------------ + +### Page title in links + +Using the fix to +[[bugs/pagetitle_function_does_not_respect_meta_titles]] from +[[intrigeri]]'s `meta` branch, the generated links' text is based on +the page titles set with the [[meta|plugins/meta]] plugin. This has to +be merged into ikiwiki upstream, though. + +Robustness tests +---------------- + +### Enabling/disabling the plugin + +- enabling the plugin with `po_translatable_pages` set to blacklist: **OK** +- enabling the plugin with `po_translatable_pages` set to whitelist: **OK** +- enabling the plugin without `po_translatable_pages` set: **OK** +- disabling the plugin: **OK** + +### Changing the plugin config -### page titles +- adding existing pages to `po_translatable_pages`: **OK** +- removing existing pages from `po_translatable_pages`: **OK** +- adding a language to `po_slave_languages`: **OK** +- removing a language from `po_slave_languages`: **OK** +- changing `po_master_language`: **OK** +- replacing `po_master_language` with a language previously part of + `po_slave_languages`: needs two rebuilds, but **OK** (this is quite + a perverse test actually) -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]]. +### Creating/deleting/renaming pages -### source files format +All cases of master/slave page creation/deletion/rename, both via RCS +and via CGI, have been tested. -Markdown is supported, great, but what about others? The set of file -formats supported both in ikiwiki and po4a probably is greater than -`{markdown}`. Warning: the po4a modules are the place where one can -expect security issues. +### Misc -Translation quality assurance ------------------------------ +- general test with `usedirs` disabled: **OK** +- general test with `indexpages` enabled: **not OK** +- general test with `po_link_to=default` with `userdirs` enabled: **OK** +- general test with `po_link_to=default` with `userdirs` disabled: **OK** -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. +Misc. bugs +---------- -A new `cansave` type of hook would be needed to implement this. +Documentation +------------- -Note: committing to the underlying repository is a way to bypass -this check. +Maybe write separate documentation depending on the people it targets: +translators, wiki administrators, hackers. This plugin may be complex +enough to deserve this.