recursion when we are unable to convert a localized error message to the
client's encoding. We've been over this ground before, but as reported by
Ibrar Ahmed, it still didn't work in the case of conversion failures for
the conversion-failure message itself :-(. Fix by installing a "circuit
breaker" that disables attempts to localize this message once we get into
recursion trouble.
Patch all supported branches, because it is in fact broken in all of them;
though I had to add some missing translations to the older branches in
order to expose the failure in the particular test case I was using.
database via builtin functions, as recently discussed on -hackers.
chr() now returns a character in the database encoding. For UTF8 encoded databases
the argument is treated as a Unicode code point. For other multi-byte encodings
the argument must designate a strict ascii character, or an error is raised,
as is also the case if the argument is 0.
ascii() is adjusted so that it remains the inverse of chr().
The two argument form of convert() is gone, and the three argument form now
takes a bytea first argument and returns a bytea. To cover this loss three new
functions are introduced:
. convert_from(bytea, name) returns text - converts the first argument from the
named encoding to the database encoding
. convert_to(text, name) returns bytea - converts the first argument from the
database encoding to the named encoding
. length(bytea, name) returns int - gives the length of the first argument in
characters in the named encoding
page about the maximum UTF8 sequence length we support (4 bytes since 8.1,
3 before that). pg_utf2wchar_with_len never got updated to support 4-byte
characters at all, and in any case had a buffer-overrun risk in that it
could produce multiple pg_wchars from what mblen claims to be just one UTF8
character. The only reason we don't have a major security hole is that most
callers allocate worst-case output buffers; the sole exception in released
versions appears to be pre-8.2 iwchareq() (ie, ILIKE), which can be crashed
due to zeroing out its return address --- but AFAICS that can't be exploited
for anything more than a crash, due to inability to control what gets written
there. Per report from James Russell and Michael Fuhr.
Pre-8.1 the risk is much less, but I still think pg_utf2wchar_with_len's
behavior given an incomplete final character risks buffer overrun, so
back-patch that logic change anyway.
This patch also makes sure that UTF8 sequences exceeding the supported
length (whichever it is) are consistently treated as error cases, rather
than being treated like a valid shorter sequence in some places.
characters in all cases. Formerly we mostly just threw warnings for invalid
input, and failed to detect it at all if no encoding conversion was required.
The tighter check is needed to defend against SQL-injection attacks as per
CVE-2006-2313 (further details will be published after release). Embedded
zero (null) bytes will be rejected as well. The checks are applied during
input to the backend (receipt from client or COPY IN), so it no longer seems
necessary to check in textin() and related routines; any string arriving at
those functions will already have been validated. Conversion failure
reporting (for characters with no equivalent in the destination encoding)
has been cleaned up and made consistent while at it.
Also, fix a few longstanding errors in little-used encoding conversion
routines: win1251_to_iso, win866_to_iso, euc_tw_to_big5, euc_tw_to_mic,
mic_to_euc_tw were all broken to varying extents.
Patches by Tatsuo Ishii and Tom Lane. Thanks to Akio Ishida and Yasuo Ohgaki
for identifying the security issues.
up a bunch of the support utilities.
In src/backend/utils/mb/Unicode remove nearly duplicate copies of the
UCS_to_XXX perl script and replace with one version to handle all generic
files. Update the Makefile so that it knows about all the map files.
This produces a slight difference in some of the map files, using a
uniform naming convention and not mapping the null character.
In src/backend/utils/mb/conversion_procs create a master utf8<->win
codepage function like the ISO 8859 versions instead of having a separate
handler for each conversion.
There is an externally visible change in the name of the win1258 to utf8
conversion. According to the documentation notes, it was named
incorrectly and this changes it to a standard name.
Running the Unicode mapping perl scripts has shown some additional mapping
changes in koi8r and iso8859-7.
If the second output column value is 'a\nb', the 'b' should appear
in the second display column, rather than the first column as it
does now.
Change libpq's PQdsplen() to return more useful values.
> Note: this changes the PQdsplen function, it can now return zero or
> minus one which was not possible before. It doesn't appear anyone is
> actually using the functions other than psql but it is a change. The
> functions are not actually documentated anywhere so it's not like we're
> breaking a defined interface. The new semantics follow the Unicode
> standard.
BACKWARD COMPATIBLE CHANGE.
The only user-visible change I saw in the regression tests is that a
SELECT * on a table where all the columns have been dropped doesn't
return a blank line like before. This seems like a step forward.
Martijn van Oosterhout
#define HIGHBIT (0x80)
#define IS_HIGHBIT_SET(ch) ((unsigned char)(ch) & HIGHBIT)
and removed CSIGNBIT and mapped it uses to HIGHBIT. I have also added
uses for IS_HIGHBIT_SET where appropriate. This change is
purely for code clarity.
See:
Subject: [HACKERS] bugs with certain Asian multibyte charsets
From: Tatsuo Ishii <ishii@sraoss.co.jp>
To: pgsql-hackers@postgresql.org
Date: Sat, 24 Dec 2005 18:25:33 +0900 (JST)
for more details/
> > > > It was made to cope with encoding such as an Asian bloc in 7.2Beta2.
> > > >
> > > > Added ServerEncoding
> > > > Korean (JOHAB), Thai (WIN874),
> > > > Vietnamese (TCVN), Arabic (WIN1256)
> > > >
> > > > Added ClientEncoding
> > > > Simplified Chinese (GBK), Korean (UHC)
> > > >
> > > >
> > > >
> http://www.sankyo-unyu.co.jp/Pool/postgresql-7.2b2.newencoding.diff.tar.gz
> > > > (608K)
> > >
> > > Looks good. I need some people to review this for me.
> >
> > For me they look good too. The only missing part is a
> > documentation. I will ask him to write it up. If he couldn't, I will
> > do it for him.
> > > The diff is 3mb
> > > but appears to address only additions to multibyte. I have attached a
> > > list of files it modifies. Also, look at the sizes of the mb/
> > > directory. It is getting large:
> > >
> > > 4 ./CVS
> > > 6 ./Unicode/CVS
> > > 3433 ./Unicode
> > > 6197 .
> >
> > Yes. We definitely need the on-the-fly encoding addition capability:
> > i.e. CREATE CHRACTER SET in the future...
> > --
> > Tatsuo Ishii
> >
> >
Address chainge.
http://www.sankyo-unyu.co.jp/Pool/postgresql-7.2.newencoding.diff.gz
Add PsqlODBC and document ...etc patch.
Eiji Tokuya
-------------------------------------------------------------------
Subject: Re: [PATCHES] encoding names
From: Karel Zak <zakkr@zf.jcu.cz>
To: Peter Eisentraut <peter_e@gmx.net>
Cc: pgsql-patches <pgsql-patches@postgresql.org>
Date: Fri, 31 Aug 2001 17:24:38 +0200
On Thu, Aug 30, 2001 at 01:30:40AM +0200, Peter Eisentraut wrote:
> > - convert encoding 'name' to 'id'
>
> I thought we decided not to add functions returning "new" names until we
> know exactly what the new names should be, and pending schema
Ok, the patch not to add functions.
> better
>
> ...(): encoding name too long
Fixed.
I found new bug in command/variable.c in parse_client_encoding(), nobody
probably never see this error:
if (pg_set_client_encoding(encoding))
{
elog(ERROR, "Conversion between %s and %s is not supported",
value, GetDatabaseEncodingName());
}
because pg_set_client_encoding() returns -1 for error and 0 as true.
It's fixed too.
IMHO it can be apply.
Karel
PS:
* following files are renamed:
src/utils/mb/Unicode/KOI8_to_utf8.map -->
src/utils/mb/Unicode/koi8r_to_utf8.map
src/utils/mb/Unicode/WIN_to_utf8.map -->
src/utils/mb/Unicode/win1251_to_utf8.map
src/utils/mb/Unicode/utf8_to_KOI8.map -->
src/utils/mb/Unicode/utf8_to_koi8r.map
src/utils/mb/Unicode/utf8_to_WIN.map -->
src/utils/mb/Unicode/utf8_to_win1251.map
* new file:
src/utils/mb/encname.c
* removed file:
src/utils/mb/common.c
--
Karel Zak <zakkr@zf.jcu.cz>
http://home.zf.jcu.cz/~zakkr/
C, PostgreSQL, PHP, WWW, http://docs.linux.cz, http://mape.jcu.cz
