Commit Graph

1889 Commits

Author SHA1 Message Date
Michael Paquier e0a09d4e35 Fix inconsistent error handling for GSS encryption in PQconnectPoll()
The error cases for TLS and GSS encryption were inconsistent.  After TLS
fails, the connection is marked as dead and follow-up calls of
PQconnectPoll() would return immediately, but GSS encryption was not
doing that, so the connection would still have been allowed to enter the
GSS handling code.  This was handled incorrectly when gssencmode was set
to "require".  "prefer" was working correctly, and this could not happen
under "disable" as GSS encryption would not be attempted.

This commit makes the error handling of GSS encryption on par with TLS
portion, fixing the case of gssencmode=require.

Reported-by: Jacob Champion
Author: Michael Paquier
Reviewed-by: Jacob Champion, Stephen Frost
Discussion: https://postgr.es/m/23787477-5fe1-a161-6d2a-e459f74c4713@timescale.com
Backpatch-through: 12
2023-03-13 16:36:20 +09:00
Peter Eisentraut 6a3002715e meson: Make auto the default of the ssl option
The 'ssl' option is of type 'combo', but we add a choice 'auto' that
simulates the behavior of a feature option.  This way, openssl is used
automatically by default if present, but we retain the ability to
potentially select another ssl library.

Author: Nazir Bilal Yavuz <byavuz81@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/ad65ffd1-a9a7-fda1-59c6-f7dc763c3051%40enterprisedb.com
2023-03-13 07:04:11 +01:00
Michael Paquier b6dfee28f2 Run pgindent on libpq's fe-auth.c, fe-auth-scram.c and fe-connect.c
A patch sent by Jacob Champion has been touching this area of the code,
and the set of changes done in a9e9a9f has made a run of pgindent on
these files a bit annoying to handle.  So let's clean up a bit the area,
first, to ease the work on follow-up patches.

Discussion: https://postgr.es/m/9e5a8ccddb8355ea9fa4b75a1e3a9edc88a70cd3.camel@vmware.com
2023-03-09 15:09:45 +09:00
Peter Eisentraut 2a71ad64cb Break up long GETTEXT_FILES lists
One file per line seems best.  We already did this in some cases.
This adopts the same format everywhere (except in some cases where the
list reasonably fits on one line).
2023-03-08 15:05:43 +01:00
Heikki Linnakangas 5e044471a1 Check for unbounded authentication exchanges in libpq.
A couple of code paths in CONNECTION_AWAITING_RESPONSE will eagerly read
bytes off a connection that should be closed. Don't let a misbehaving
server chew up client resources here; a v2 error can't be infinitely
long, and a v3 error should be bounded by its original message length.

For the existing error_return cases, I added some additional error
messages for symmetry with the new ones, and cleaned up some message
rot.

Author: Jacob Champion
Discussion: https://www.postgresql.org/message-id/8e729daf-7d71-6965-9687-8bc0630599b3%40timescale.com
2023-02-22 21:27:38 +02:00
Michael Paquier 9244c11afe Fix handling of SCRAM-SHA-256's channel binding with RSA-PSS certificates
OpenSSL 1.1.1 and newer versions have added support for RSA-PSS
certificates, which requires the use of a specific routine in OpenSSL to
determine which hash function to use when compiling it when using
channel binding in SCRAM-SHA-256.  X509_get_signature_nid(), that is the
original routine the channel binding code has relied on, is not able to
determine which hash algorithm to use for such certificates.  However,
X509_get_signature_info(), new to OpenSSL 1.1.1, is able to do it.  This
commit switches the channel binding logic to rely on
X509_get_signature_info() over X509_get_signature_nid(), which would be
the choice when building with 1.1.1 or newer.

The error could have been triggered on the client or the server, hence
libpq and the backend need to have their related code paths patched.
Note that attempting to load an RSA-PSS certificate with OpenSSL 1.1.0
or older leads to a failure due to an unsupported algorithm.

The discovery of relying on X509_get_signature_info() comes from Jacob,
the tests have been written by Heikki (with few tweaks from me), while I
have bundled the whole together while adding the bits needed for MSVC
and meson.

This issue exists since channel binding exists, so backpatch all the way
down.  Some tests are added in 15~, triggered if compiling with OpenSSL
1.1.1 or newer, where the certificate and key files can easily be
generated for RSA-PSS.

Reported-by: Gunnar "Nick" Bluth
Author: Jacob Champion, Heikki Linnakangas
Discussion: https://postgr.es/m/17760-b6c61e752ec07060@postgresql.org
Backpatch-through: 11
2023-02-15 10:12:16 +09:00
Michael Paquier 71c37797d7 Properly NULL-terminate GSS receive buffer on error packet reception
pqsecure_open_gss() includes a code path handling error messages with
v2-style protocol messages coming from the server.  The client-side
buffer holding the error message does not force a NULL-termination, with
the data of the server getting copied to the errorMessage of the
connection.  Hence, it would be possible for a server to send an
unterminated string and copy arbitrary bytes in the buffer receiving the
error message in the client, opening the door to a crash or even data
exposure.

As at this stage of the authentication process the exchange has not been
completed yet, this could be abused by an attacker without Kerberos
credentials.  Clients that have a valid kerberos cache are vulnerable as
libpq opportunistically requests for it except if gssencmode is
disabled.

Author: Jacob Champion
Backpatch-through: 12
Security: CVE-2022-41862
2023-02-06 11:20:07 +09:00
Bruce Momjian c8e1ba736b Update copyright for 2023
Backpatch-through: 11
2023-01-02 15:00:37 -05:00
Andrew Dunstan 8284cf5f74 Add copyright notices to meson files
Discussion: https://postgr.es/m/222b43a5-2fb3-2c1b-9cd0-375d376c8246@dunslane.net
2022-12-20 07:54:39 -05:00
Michael Paquier b3bb7d12af Remove hardcoded dependency to cryptohash type in the internals of SCRAM
SCRAM_KEY_LEN was a variable used in the internal routines of SCRAM to
size a set of fixed-sized arrays used in the SHA and HMAC computations
during the SASL exchange or when building a SCRAM password.  This had a
hard dependency on SHA-256, reducing the flexibility of SCRAM when it
comes to the addition of more hash methods.  A second issue was that
SHA-256 is assumed as the cryptohash method to use all the time.

This commit renames SCRAM_KEY_LEN to a more generic SCRAM_KEY_MAX_LEN,
which is used as the size of the buffers used by the internal routines
of SCRAM.  This is aimed at tracking centrally the maximum size
necessary for all the hash methods supported by SCRAM.  A global
variable has the advantage of keeping the code in its simplest form,
reducing the need of more alloc/free logic for all the buffers used in
the hash calculations.

A second change is that the key length (SHA digest length) and hash
types are now tracked by the state data in the backend and the frontend,
the common portions being extended to handle these as arguments by the
internal routines of SCRAM.  There are a few RFC proposals floating
around to extend the SCRAM protocol, including some to use stronger
cryptohash algorithms, so this lifts some of the existing restrictions
in the code.

The code in charge of parsing and building SCRAM secrets is extended to
rely on the key length and on the cryptohash type used for the exchange,
assuming currently that only SHA-256 is supported for the moment.  Note
that the mock authentication simply enforces SHA-256.

Author: Michael Paquier
Reviewed-by: Peter Eisentraut, Jonathan Katz
Discussion: https://postgr.es/m/Y5k3Qiweo/1g9CG6@paquier.xyz
2022-12-20 08:53:22 +09:00
Michael Paquier d74a366aa2 Fix comment in fe-auth-scram.c
The frontend-side routine in charge of building a SCRAM verifier
mentioned that the restrictions applying to SASLprep on the password
with the encoding are described at the top of fe-auth-scram.c, but this
information is in auth-scram.c.

This is wrong since 8f8b9be, so backpatch all the way down as this is an
important documentation bit.

Spotted while reviewing a different patch.

Backpatch-through: 11
2022-11-30 08:37:59 +09:00
Peter Eisentraut bbf9c282ce libpq: Handle NegotiateProtocolVersion message
Before, receiving a NegotiateProtocolVersion message would result in a
confusing error message like

    expected authentication request from server, but received v

This adds proper handling of this protocol message and produces an
on-topic error message from it.

Reviewed-by: Jacob Champion <jchampion@timescale.com>
Reviewed-by: Nathan Bossart <nathandbossart@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/f9c7862f-b864-8ef7-a861-c4638c83e209%40enterprisedb.com
2022-11-17 15:42:09 +01:00
Peter Eisentraut dce92e59b1 libpq: Correct processing of startup response messages
After sending a startup message, libpq expects either an error
response ('E') or an authentication request ('R').  Before processing
the message, it ensures it has read enough bytes to correspond to the
length specified in the message.  However, when processing the 'R'
message, if an EOF status is returned it loops back waiting for more
input, even though we already checked that we have enough input.  In
this particular case, this is probably not reachable anyway, because
other code ensures we have enough bytes for an authentication request
message, but the code is wrong and misleading.  In the more general
case, processing a faulty message could result in an EOF status, which
would then result in an infinite loop waiting for the end of a message
that will never come.  The correction is to make this an error.

Reported-by: Jacob Champion <jchampion@timescale.com>
Discussion: https://www.postgresql.org/message-id/flat/f9c7862f-b864-8ef7-a861-c4638c83e209@enterprisedb.com
2022-11-17 14:12:04 +01:00
Peter Eisentraut a9e9a9f32b libpq error message refactoring, part 2
This applies the new APIs to the code.

Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://www.postgresql.org/message-id/flat/7c0232ef-7b44-68db-599d-b327d0640a77@enterprisedb.com
2022-11-15 12:16:50 +01:00
Peter Eisentraut 0873b2d354 libpq error message refactoring
libpq now contains a mix of error message strings that end with
newlines and don't end with newlines, due to some newer code paths
with new ways of passing errors around.  This leads to confusion and
mistakes both during development and translation.

This adds new functions libpq_append_error() and
libpq_append_conn_error() that encapsulate common code paths for
producing error message strings.  Notably, these functions append the
newline, so that the string appearing in the code does not end with a
newline.  This makes (almost) all error message strings in libpq
uniform in this regard (and also consistent with how we handle it
outside of libpq code).  (There are a few exceptions that are
difficult to fit into this scheme, but they are only a few.)

Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://www.postgresql.org/message-id/flat/7c0232ef-7b44-68db-599d-b327d0640a77@enterprisedb.com
2022-11-15 12:16:50 +01:00
Peter Eisentraut 45d5ecab49 libpq: Add missing newlines to error messages 2022-11-13 21:09:09 +01:00
Peter Eisentraut 062e133f6d libpq: Remove unneeded cast and adjust format placeholder 2022-11-13 21:09:05 +01:00
Alvaro Herrera db1b931a4e
libpq: Reset singlerow flag correctly in pipeline mode
When a query whose results were requested in single-row mode is the last
in the queue by the time those results are being read, the single-row
flag was not being reset, because we were returning early from
pqPipelineProcessQueue.  Move that stanza up so that the flag is always
reset at the end of sending that query's results.

Add a test for the situation.

Backpatch to 14.

Author: Denis Laxalde <denis.laxalde@dalibo.com>
Discussion: https://postgr.es/m/01af18c5-dacc-a8c8-07ee-aecc7650c3e8@dalibo.com
2022-10-14 19:06:26 +02:00
Andres Freund e5555657ba meson: Add support for building with precompiled headers
This substantially speeds up building for windows, due to the vast amount of
headers included via windows.h. A cross build from linux targetting mingw goes
from

994.11user 136.43system 0:31.58elapsed 3579%CPU
to
422.41user 89.05system 0:14.35elapsed 3562%CPU

The wins on windows are similar-ish (but I don't have a system at hand just
now for actual numbers). Targetting other operating systems the wins are far
smaller (tested linux, macOS, FreeBSD).

For now precompiled headers are disabled by default, it's not clear how well
they work on all platforms. E.g. on FreeBSD gcc doesn't seem to have working
support, but clang does.

When doing a full build precompiled headers are only beneficial for targets
with multiple .c files, as meson builds a separate precompiled header for each
target (so that different compilation options take effect). This commit
therefore only changes target with at least two .c files to use precompiled
headers.

Because this commit adds b_pch=false to the default_options new build
directories will have precompiled headers disabled by default, however
existing build directories will continue use the default value of b_pch, which
is true.

Note that using precompiled headers with ccache requires setting
CCACHE_SLOPPINESS=pch_defines,time_macros to get hits.

Reviewed-by: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
Reviewed-by: Justin Pryzby <pryzby@telsasoft.com>
Discussion: https://postgr.es/m/CA+hUKG+50eOUbN++ocDc0Qnp9Pvmou23DSXu=ZA6fepOcftKqA@mail.gmail.com
Discussion: https://postgr.es/m/c5736f70-bb6d-8d25-e35c-e3d886e4e905@enterprisedb.com
Discussion: https://postgr.es/m/20190826054000.GE7005%40paquier.xyz
2022-10-06 17:19:30 -07:00
David Rowley cd4e8caaa0 Fix final warnings produced by -Wshadow=compatible-local
I thought I had these in d8df67bb1, but per report from Andres Freund, I
missed some.

Reviewed-by: Andres Freund
Discussion: https://postgr.es/m/20221005214052.c4tkudawyp5wxt3c@awork3.anarazel.de
2022-10-07 13:13:27 +13:00
Andres Freund 902ab2fcef meson: Add windows resource files
The generated resource files aren't exactly the same ones as the old
buildsystems generate. Previously "InternalName" and "OriginalFileName" were
mostly wrong / not set (despite being required), but that was hard to fix in
at least the make build. Additionally, the meson build falls back to a
"auto-generated" description when not set, and doesn't set it in a few cases -
unlikely that anybody looks at these descriptions in detail.

Author: Andres Freund <andres@anarazel.de>
Author: Nazir Bilal Yavuz <byavuz81@gmail.com>
Reviewed-by: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
2022-10-05 09:56:05 -07:00
Andres Freund 089c0bc7a7 meson: libpq: Revise static / shared library setup
Improvements:
- we don't need -DFRONTEND for libpq anymore since 1d77afefbd
- the .pc file contents for a static libpq were wrong (referencing
  {pgport, common}_shlib)
- incidentally fixes meson not supporting link_whole on AIX yet
- added explanatory comments

Previously I tried to avoid building libpq's sources twice, once for the
static and once for the shared library. We could still do so, but it's not
clear that it's worth the complication.

Reviewed-by: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
2022-10-05 09:56:05 -07:00
Tom Lane 4e4f7b9fcc Adjust PQsslAttributeNames() to match PQsslAttribute().
Currently, PQsslAttributeNames() returns the same list of attribute
names regardless of its conn parameter.  This patch changes it to
have behavior parallel to what 80a05679d installed for PQsslAttribute:
you get OpenSSL's attributes if conn is NULL or is an SSL-encrypted
connection, or an empty list if conn is a non-encrypted connection.
The point of this is to have sensible connection-dependent behavior
in case we ever support multiple SSL libraries.  The behavior for
NULL can be defined as "the attributes for the default SSL library",
parallel to what PQsslAttribute(NULL, "library") does.

Since this is mostly just future-proofing, no back-patch.

Discussion: https://postgr.es/m/17625-fc47c78b7d71b534@postgresql.org
2022-09-30 10:26:47 -04:00
Tom Lane 80a05679d5 Fix bogus behavior of PQsslAttribute(conn, "library").
Commit ebc8b7d44 intended to change the behavior of
PQsslAttribute(NULL, "library"), but accidentally also changed
what happens with a non-NULL conn pointer.  Undo that so that
only the intended behavior change happens.  Clarify some
associated documentation.

Per bug #17625 from Heath Lord.  Back-patch to v15.

Discussion: https://postgr.es/m/17625-fc47c78b7d71b534@postgresql.org
2022-09-29 17:28:09 -04:00
Alvaro Herrera 0032a54567
Remove PQsendQuery support in pipeline mode
The extended query protocol implementation I added in commit
acb7e4eb6b has bugs when used in pipeline mode.  Rather than spend
more time trying to fix it, remove that code and make the function rely
on simple query protocol only, meaning it can no longer be used in
pipeline mode.

Users can easily change their applications to use PQsendQueryParams
instead.  We leave PQsendQuery in place for Postgres 14, just in case
somebody is using it and has not hit the mentioned bugs; but we should
recommend that it not be used.

Backpatch to 15.

Per bug report from Gabriele Varrazzo.
Discussion: https://postgr.es/m/CA+mi_8ZGSQNmW6-mk_iSR4JZB_LJ4ww3suOF+1vGNs3MrLsv4g@mail.gmail.com
2022-09-23 18:21:22 +02:00
Andres Freund e6927270cd meson: Add initial version of meson based build system
Autoconf is showing its age, fewer and fewer contributors know how to wrangle
it. Recursive make has a lot of hard to resolve dependency issues and slow
incremental rebuilds. Our home-grown MSVC build system is hard to maintain for
developers not using Windows and runs tests serially. While these and other
issues could individually be addressed with incremental improvements, together
they seem best addressed by moving to a more modern build system.

After evaluating different build system choices, we chose to use meson, to a
good degree based on the adoption by other open source projects.

We decided that it's more realistic to commit a relatively early version of
the new build system and mature it in tree.

This commit adds an initial version of a meson based build system. It supports
building postgres on at least AIX, FreeBSD, Linux, macOS, NetBSD, OpenBSD,
Solaris and Windows (however only gcc is supported on aix, solaris). For
Windows/MSVC postgres can now be built with ninja (faster, particularly for
incremental builds) and msbuild (supporting the visual studio GUI, but
building slower).

Several aspects (e.g. Windows rc file generation, PGXS compatibility, LLVM
bitcode generation, documentation adjustments) are done in subsequent commits
requiring further review. Other aspects (e.g. not installing test-only
extensions) are not yet addressed.

When building on Windows with msbuild, builds are slower when using a visual
studio version older than 2019, because those versions do not support
MultiToolTask, required by meson for intra-target parallelism.

The plan is to remove the MSVC specific build system in src/tools/msvc soon
after reaching feature parity. However, we're not planning to remove the
autoconf/make build system in the near future. Likely we're going to keep at
least the parts required for PGXS to keep working around until all supported
versions build with meson.

Some initial help for postgres developers is at
https://wiki.postgresql.org/wiki/Meson

With contributions from Thomas Munro, John Naylor, Stone Tickle and others.

Author: Andres Freund <andres@anarazel.de>
Author: Nazir Bilal Yavuz <byavuz81@gmail.com>
Author: Peter Eisentraut <peter@eisentraut.org>
Reviewed-By: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
Discussion: https://postgr.es/m/20211012083721.hvixq4pnh2pixr3j@alap3.anarazel.de
2022-09-21 22:37:17 -07:00
Peter Geoghegan a601366a46 Harmonize more parameter names in bulk.
Make sure that function declarations use names that exactly match the
corresponding names from function definitions in optimizer, parser,
utility, libpq, and "commands" code, as well as in remaining library
code.  Do the same for all code related to frontend programs (with the
exception of pg_dump/pg_dumpall related code).

Like other recent commits that cleaned up function parameter names, this
commit was written with help from clang-tidy.  Later commits will handle
ecpg and pg_dump/pg_dumpall.

Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: David Rowley <dgrowleyml@gmail.com>
Discussion: https://postgr.es/m/CAH2-WznJt9CMM9KJTMjJh_zbL5hD9oX44qdJ4aqZtjFi-zA3Tg@mail.gmail.com
2022-09-20 13:09:30 -07:00
Michael Paquier b1ec7f47e3 Cleanup more code and comments related to Windows NT4 (XP days)
All the code and comments cleaned up here is irrelevant since 495ed0e.
Note that this removes an assumption that CreateRestrictedToken() may
not exist, something that could have happened when running under Windows
NT as the code stated.  Rather than assuming that it may not exist, this
causes pg_ctl to fail hard if the function cannot be loaded.

Reported-by: Justin Pryzby
Discussion: https://postgr.es/m/20220826112637.GD2342@telsasoft.com
2022-08-30 09:52:58 +09:00
Tom Lane 7fed801135 Clean up inconsistent use of fflush().
More than twenty years ago (79fcde48b), we hacked the postmaster
to avoid a core-dump on systems that didn't support fflush(NULL).
We've mostly, though not completely, hewed to that rule ever since.
But such systems are surely gone in the wild, so in the spirit of
cleaning out no-longer-needed portability hacks let's get rid of
multiple per-file fflush() calls in favor of using fflush(NULL).

Also, we were fairly inconsistent about whether to fflush() before
popen() and system() calls.  While we've received no bug reports
about that, it seems likely that at least some of these call sites
are at risk of odd behavior, such as error messages appearing in
an unexpected order.  Rather than expend a lot of brain cells
figuring out which places are at hazard, let's just establish a
uniform coding rule that we should fflush(NULL) before these calls.
A no-op fflush() is surely of trivial cost compared to launching
a sub-process via a shell; while if it's not a no-op then we likely
need it.

Discussion: https://postgr.es/m/2923412.1661722825@sss.pgh.pa.us
2022-08-29 13:55:41 -04:00
Thomas Munro bcc8b14ef6 Remove configure probe for sockaddr_in6 and require AF_INET6.
SUSv3 <netinet/in.h> defines struct sockaddr_in6, and all targeted Unix
systems have it.  Windows has it in <ws2ipdef.h>.  Remove the configure
probe, the macro and a small amount of dead code.

Also remove a mention of IPv6-less builds from the documentation, since
there aren't any.

This is similar to commits f5580882 and 077bf2f2 for Unix sockets.  Even
though AF_INET6 is an "optional" component of SUSv3, there are no known
modern operating system without it, and it seems even less likely to be
omitted from future systems than AF_UNIX.

Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/CA+hUKGKErNfhmvb_H0UprEmp4LPzGN06yR2_0tYikjzB-2ECMw@mail.gmail.com
2022-08-26 10:18:30 +12:00
Peter Eisentraut 28ec316787 libpq code should use libpq_gettext(), not _()
Fix some wrong use and install a safeguard against future mistakes.
2022-08-25 20:46:58 +02:00
Peter Eisentraut 869e56a399 Message style adjustment 2022-08-23 21:51:07 +02:00
Andres Freund 1d77afefbd Don't define FRONTEND for libpq
Not needed anymore after 7143b3e821.

Discussion: https://postgr.es/m/20220820194550.725755r6fj2ro3rx@awork3.anarazel.de
2022-08-22 20:39:30 -07:00
Peter Eisentraut 1509abe2c5 Remove remaining mentions of UNSAFE_STAT_OK
The last use was removed by bed90759fc.

Discussion: https://www.postgresql.org/message-id/flat/01229f9a-b358-d71e-31ae-4c0855d73cbc%40enterprisedb.com
2022-08-20 13:53:21 +02:00
Thomas Munro f340f97a13 mstcpip.h is not missing on MinGW.
Remove a small difference between MinGW and MSVC builds which isn't
needed for modern MinGW, noticed in passing.

Discussion: https://postgr.es/m/CA+hUKGKErNfhmvb_H0UprEmp4LPzGN06yR2_0tYikjzB-2ECMw@mail.gmail.com
2022-08-18 16:31:11 +12:00
Thomas Munro 2492fe49dc Remove configure probe for netinet/tcp.h.
<netinet/tcp.h> is in SUSv3 and all targeted Unix systems have it.
For Windows, we can provide a stub include file, to avoid some #ifdef
noise.

Discussion: https://postgr.es/m/CA+hUKGKErNfhmvb_H0UprEmp4LPzGN06yR2_0tYikjzB-2ECMw@mail.gmail.com
2022-08-18 16:31:11 +12:00
Tom Lane bb9237a129 Add missing bad-PGconn guards in libpq entry points.
There's a convention that externally-visible libpq functions should
check for a NULL PGconn pointer, and fail gracefully instead of
crashing.  PQflush() and PQisnonblocking() didn't get that memo
though.  Also add a similar check to PQdefaultSSLKeyPassHook_OpenSSL;
while it's not clear that ordinary usage could reach that with a
null conn pointer, it's cheap enough to check, so let's be consistent.

Daniele Varrazzo and Tom Lane

Discussion: https://postgr.es/m/CA+mi_8Zm_mVVyW1iNFgyMd9Oh0Nv8-F+7Y3-BqwMgTMHuo_h2Q@mail.gmail.com
2022-08-15 15:40:07 -04:00
Thomas Munro 52ea29045b Remove configure probe for gethostbyname_r.
It was only used by src/port/getaddrinfo.c, removed by the previous
commit.

Discussion: https://postgr.es/m/CA%2BhUKGJFLPCtAC58EAimF6a6GPw30TU_59FUY%3DGWB_kC%3DJEmVQ%40mail.gmail.com
2022-08-14 09:57:48 +12:00
Thomas Munro 5579388d2d Remove replacement code for getaddrinfo.
SUSv3, all targeted Unixes and modern Windows have getaddrinfo() and
related interfaces.  Drop the replacement implementation, and adjust
some headers slightly to make sure that the APIs are visible everywhere
using standard POSIX headers and names.

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CA%2BhUKG%2BL_3brvh%3D8e0BW_VfX9h7MtwgN%3DnFHP5o7X2oZucY9dg%40mail.gmail.com
2022-08-14 09:53:28 +12:00
Thomas Munro f558088285 Remove HAVE_UNIX_SOCKETS.
Since HAVE_UNIX_SOCKETS is now defined unconditionally, remove the macro
and drop a small amount of dead code.

The last known systems not to have them (as far as I know at least) were
QNX, which we de-supported years ago, and Windows, which now has them.

If a new OS ever shows up with the POSIX sockets API but without working
AF_UNIX, it'll presumably still be able to compile the code, and fail at
runtime with an unsupported address family error.  We might want to
consider adding a HINT that you should turn off the option to use it if
your network stack doesn't support it at that point, but it doesn't seem
worth making the relevant code conditional at compile time.

Also adjust a couple of places in the docs and comments that referred to
builds without Unix-domain sockets, since there aren't any.  Windows
still gets a special mention in those places, though, because we don't
try to use them by default there yet.

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
Discussion: https://postgr.es/m/CA%2BhUKG%2BL_3brvh%3D8e0BW_VfX9h7MtwgN%3DnFHP5o7X2oZucY9dg%40mail.gmail.com
2022-08-14 08:46:53 +12:00
Thomas Munro 7e50b4e3c5 Remove configure probe for sys/select.h.
<sys/select.h> is in SUSv3 and every targeted Unix system has it.
Provide an empty header in src/include/port/win32 so that we can
include it unguarded even on Windows.

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CA%2BhUKG%2BL_3brvh%3D8e0BW_VfX9h7MtwgN%3DnFHP5o7X2oZucY9dg%40mail.gmail.com
2022-08-14 00:09:47 +12:00
Alvaro Herrera 0f39b70a6f
Fix [install]check in interfaces/libpq/Makefile
The common recipe when TAP tests are disabled doesn't work, because the
libpq-specific recipe wants to define the PATH environment variable, so
the starting '@' is misinterpreted as part of the command instead of
silencing said command.

Fix by setting the environment variable in a way that doesn't interfere
with the recipe.

Reported-by: Justin Pryzby <pryzby@telsasoft.com>
Discussion: https://postgr.es/m/20220720172321.GL12702@telsasoft.com
2022-07-22 20:15:11 +02:00
Tom Lane 54ba2f0623 Revert "Use wildcards instead of manually-maintained file lists in */nls.mk."
This reverts commit 617d691412.
While I still think the basic idea is attractive, we need to sort
out what happens with built .c files, and there also seem to be
VPATH issues.
2022-07-13 14:29:10 -04:00
Tom Lane 617d691412 Use wildcards instead of manually-maintained file lists in */nls.mk.
The backend already used a mechanically-generated list of *.c files,
but everywhere else we had a manually-written-out list of files in
which to seek translatable messages.  Commit b0a55e432 contains the
latest in a long line of failures to update those lists.  Rather than
manually fix its oversight, let's change to using "$(wildcard *.c)"
in all these nls.mk files.

Many of these files also have manual references to some *.c files
in other directories, most often src/common/.  Perhaps we should try
to improve that situation too; but it's a bit less clear how, so for
now just fix the local file references.

Kyotaro Horiguchi and Tom Lane

Discussion: https://postgr.es/m/20220713.160853.453362706160476128.horikyota.ntt@gmail.com
2022-07-13 12:56:42 -04:00
Alvaro Herrera e1df03b80d
Plug memory leak
Commit 054325c5ee created a memory leak in PQsendQueryInternal in case
an error occurs while sending the message.  Repair.

Backpatch to 14, like that commit.  Reported by Coverity.
2022-07-13 12:58:56 +02:00
Peter Eisentraut 88dad06b47 NLS: Put list of available languages into LINGUAS files
This moves the list of available languages from nls.mk into a separate
file called po/LINGUAS.  Advantages:

- It keeps the parts notionally managed by programmers (nls.mk)
  separate from the parts notionally managed by translators (LINGUAS).

- It's the standard practice recommended by the Gettext manual
  nowadays.

- The Meson build system also supports this layout (and of course
  doesn't know anything about our custom nls.mk), so this would enable
  sharing the list of languages between the two build systems.

(The MSVC build system currently finds all po files by globbing, so it
is not affected by this change.)

Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://www.postgresql.org/message-id/flat/557a9f5c-e871-edc7-2f58-a4140fb65b7b@enterprisedb.com
2022-07-13 08:19:17 +02:00
Alvaro Herrera 054325c5ee
libpq: Improve idle state handling in pipeline mode
We were going into IDLE state too soon when executing queries via
PQsendQuery in pipeline mode, causing several scenarios to misbehave in
different ways -- most notably, as reported by Daniele Varrazzo, that a
warning message is produced by libpq:
  message type 0x33 arrived from server while idle
But it is also possible, if queries are sent and results consumed not in
lockstep, for the expected mediating NULL result values from PQgetResult
to be lost (a problem which has not been reported, but which is more
serious).

Fix this by introducing two new concepts: one is a command queue element
PGQUERY_CLOSE to tell libpq to wait for the CloseComplete server
response to the Close message that is sent by PQsendQuery.  Because the
application is not expecting any PGresult from this, the mechanism to
consume it is a bit hackish.

The other concept, authored by Horiguchi-san, is a PGASYNC_PIPELINE_IDLE
state for libpq's state machine to differentiate "really idle" from
merely "the idle state that occurs in between reading results from the
server for elements in the pipeline".  This makes libpq not go fully
IDLE when the libpq command queue contains entries; in normal cases, we
only go IDLE once at the end of the pipeline, when the server response
to the final SYNC message is received.  (However, there are corner cases
it doesn't fix, such as terminating the query sequence by
PQsendFlushRequest instead of PQpipelineSync; this sort of scenario is
what requires PGQUERY_CLOSE bit above.)

This last bit helps make the libpq state machine clearer; in particular
we can get rid of an ugly hack in pqParseInput3 to avoid considering
IDLE as such when the command queue contains entries.

A new test mode is added to libpq_pipeline.c to tickle some related
problematic cases.

Reported-by: Daniele Varrazzo <daniele.varrazzo@gmail.com>
Co-authored-by: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Discussion: https://postgr.es/m/CA+mi_8bvD0_CW3sumgwPvWdNzXY32itoG_16tDYRu_1S2gV2iw@mail.gmail.com
2022-07-05 14:21:20 +02:00
Noah Misch b6a5158f98 Add Windows file version information to libpq/test programs.
Back-patch to v15, the first version to install these programs.

Discussion: https://postgr.es/m/20220501080706.GA1542365@rfd.leadboat.com
2022-07-03 13:07:17 -07:00
Peter Eisentraut 5faef9d582 Remove redundant null pointer checks before PQclear and PQconninfoFree
These functions already had the free()-like behavior of handling null
pointers as a no-op.  But it wasn't documented, so add it explicitly
to the documentation, too.

Discussion: https://www.postgresql.org/message-id/flat/dac5d2d0-98f5-94d9-8e69-46da2413593d%40enterprisedb.com
2022-07-03 20:11:05 +02:00
Peter Eisentraut 02c408e21a Remove redundant null pointer checks before free()
Per applicable standards, free() with a null pointer is a no-op.
Systems that don't observe that are ancient and no longer relevant.
Some PostgreSQL code already required this behavior, so this change
does not introduce any new requirements, just makes the code more
consistent.

Discussion: https://www.postgresql.org/message-id/flat/dac5d2d0-98f5-94d9-8e69-46da2413593d%40enterprisedb.com
2022-07-03 11:47:15 +02:00
Peter Eisentraut 3c0bcdbc66 Translation updates
Source-Git-URL: https://git.postgresql.org/git/pgtranslation/messages.git
Source-Git-Hash: 46c120873f1e906cc8dab74d8d756417e1b367f6
2022-06-27 08:19:02 +02:00
Tom Lane 2b65de7fc2 Remove misguided SSL key file ownership check in libpq.
Commits a59c79564 et al. tried to sync libpq's SSL key file
permissions checks with what we've used for years in the backend.
We did not intend to create any new failure cases, but it turns out
we did: restricting the key file's ownership breaks cases where the
client is allowed to read a key file despite not having the identical
UID.  In particular a client running as root used to be able to read
someone else's key file; and having seen that I suspect that there are
other, less-dubious use cases that this restriction breaks on some
platforms.

We don't really need an ownership check, since if we can read the key
file despite its having restricted permissions, it must have the right
ownership --- under normal conditions anyway, and the point of this
patch is that any additional corner cases where that works should be
deemed allowable, as they have been historically.  Hence, just drop
the ownership check, and rearrange the permissions check to get rid
of its faulty assumption that geteuid() can't be zero.  (Note that the
comparable backend-side code doesn't have to cater for geteuid() == 0,
since the server rejects that very early on.)

This does have the end result that the permissions safety check used
for a root user's private key file is weaker than that used for
anyone else's.  While odd, root really ought to know what she's doing
with file permissions, so I think this is acceptable.

Per report from Yogendra Suralkar.  Like the previous patch,
back-patch to all supported branches.

Discussion: https://postgr.es/m/MW3PR15MB3931DF96896DC36D21AFD47CA3D39@MW3PR15MB3931.namprd15.prod.outlook.com
2022-05-26 14:14:05 -04:00
Peter Eisentraut 6a8a7b1ccb Translation updates
Source-Git-URL: https://git.postgresql.org/git/pgtranslation/messages.git
Source-Git-Hash: dde45df385dab9032155c1f867b677d55695310c
2022-05-16 11:12:42 +02:00
Tom Lane 23e7b38bfe Pre-beta mechanical code beautification.
Run pgindent, pgperltidy, and reformat-dat-files.
I manually fixed a couple of comments that pgindent uglified.
2022-05-12 15:17:30 -04:00
Tom Lane 93909599cd libpq: drop pending pipelined commands in pqDropConnection().
The original coding did this in pqDropServerData(), which seems
fairly backwards.  Pending commands are more like already-queued
output data, which is dropped in pqDropConnection().  Moving the
operation means that we clear the command queue immediately upon
detecting connection drop, which improves the sanity of subsequent
behavior.  In particular this eliminates duplicated error message
text as a consequence of code added in b15f25446, which supposed
that a nonempty command queue must mean the prior operation is
still active.

There might be an argument for backpatching this to v14; but as with
b15f25446, I'm unsure about interactions with 618c16707.  For now,
given the lack of complaints about v14's behavior, leave it alone.

Per report from Peter Eisentraut.

Discussion: https://postgr.es/m/de57761c-b99b-3435-b0a6-474c72b1149a@enterprisedb.com
2022-05-12 13:08:31 -04:00
Peter Eisentraut 3aa7a3d2a3 Add missing source files to nls.mk 2022-05-11 06:16:56 +02:00
Daniel Gustafsson 0432490d29 Rename libpq test programs with libpq_ prefix
The testclient and uri-regress programs in the libpq test suite had
quite generic names which didn't convey much meaning. Since they are
installed as part of the MSVC test runs, ensure that their purpose
is a little bit clearer by renaming with a libpq_ prefix. While at
it rename uri-regress to uri_regress to avoid mixing dash and under-
score in the same filename.

Reported-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/20220501080706.GA1542365@rfd.leadboat.com
2022-05-04 14:15:25 +02:00
Tom Lane 914611ea73 Fix missed cases in libpq's error handling.
Commit 618c16707 invented an "error_result" flag in PGconn, which
intends to represent the state that we have an error condition and
need to build a PGRES_FATAL_ERROR PGresult from the message text in
conn->errorMessage, but have not yet done so.  (Postponing construction
of the error object simplifies dealing with out-of-memory conditions
and with concatenation of messages for multiple errors.)  For nearly all
purposes, this "virtual" PGresult object should act the same as if it
were already materialized.  But a couple of places in fe-protocol3.c
didn't get that memo, and were only testing conn->result as they used
to, without also checking conn->error_result.

In hopes of reducing the probability of similar mistakes in future,
I invented a pgHavePendingResult() macro that includes both tests.

Per report from Peter Eisentraut.

Discussion: https://postgr.es/m/b52277b9-fa66-b027-4a37-fb8989c73ff8@enterprisedb.com
2022-04-21 17:12:49 -04:00
Alvaro Herrera 24d2b2680a
Remove extraneous blank lines before block-closing braces
These are useless and distracting.  We wouldn't have written the code
with them to begin with, so there's no reason to keep them.

Author: Justin Pryzby <pryzby@telsasoft.com>
Discussion: https://postgr.es/m/20220411020336.GB26620@telsasoft.com
Discussion: https://postgr.es/m/attachment/133167/0016-Extraneous-blank-lines.patch
2022-04-13 19:16:02 +02:00
Peter Eisentraut 465ab24296 libpq: Fix pkg-config without OpenSSL
Do not add OpenSSL dependencies to libpq pkg-config file if OpenSSL is
not enabled.  Oversight in beff361bc1.

Author: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/20220331163759.32665-1-fontaine.fabrice%40gmail.com
2022-04-01 17:15:24 +02:00
Peter Eisentraut c1932e5428 libpq: Allow IP address SANs in server certificates
The current implementation supports exactly one IP address in a server
certificate's Common Name, which is brittle (the strings must match
exactly).  This patch adds support for IPv4 and IPv6 addresses in a
server's Subject Alternative Names.

Per discussion on-list:

- If the client's expected host is an IP address, we allow fallback to
  the Subject Common Name if an iPAddress SAN is not present, even if
  a dNSName is present.  This matches the behavior of NSS, in
  violation of the relevant RFCs.

- We also, counter-intuitively, match IP addresses embedded in dNSName
  SANs.  From inspection this appears to have been the behavior since
  the SAN matching feature was introduced in acd08d76.

- Unlike NSS, we don't map IPv4 to IPv6 addresses, or vice-versa.

Author: Jacob Champion <pchampion@vmware.com>
Co-authored-by: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Co-authored-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: https://www.postgresql.org/message-id/flat/9f5f20974cd3a4091a788cf7f00ab663d5fcdffe.camel@vmware.com
2022-04-01 15:51:23 +02:00
Tom Lane 878e64d0f8 Add missing newline in one libpq error message.
Oversight in commit a59c79564.  Back-patch, as that was.
Noted by Peter Eisentraut.

Discussion: https://postgr.es/m/7f85ef6d-250b-f5ec-9867-89f0b16d019f@enterprisedb.com
2022-03-31 11:24:26 -04:00
Daniel Gustafsson ebc8b7d441 Enable SSL library detection via PQsslAttribute()
Currently, libpq client code must have a connection handle
before it can query the "library" SSL attribute.  This poses
problems if the client needs to know what SSL library is in
use before constructing a connection string.

Allow PQsslAttribute(NULL, "library") to return the library
in use -- currently, just "OpenSSL" or NULL. The new behavior
is announced with the LIBPQ_HAS_SSL_LIBRARY_DETECTION feature
macro, allowing clients to differentiate between a libpq that
was compiled without SSL support and a libpq that's just too
old to tell.

Author: Jacob Champion <pchampion@vmware.com>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: https://postgr.es/m/4c8b76ef434a96627170a31c3acd33cbfd6e41f1.camel@vmware.com
2022-03-29 14:02:45 +02:00
Alvaro Herrera 7103ebb7aa
Add support for MERGE SQL command
MERGE performs actions that modify rows in the target table using a
source table or query. MERGE provides a single SQL statement that can
conditionally INSERT/UPDATE/DELETE rows -- a task that would otherwise
require multiple PL statements.  For example,

MERGE INTO target AS t
USING source AS s
ON t.tid = s.sid
WHEN MATCHED AND t.balance > s.delta THEN
  UPDATE SET balance = t.balance - s.delta
WHEN MATCHED THEN
  DELETE
WHEN NOT MATCHED AND s.delta > 0 THEN
  INSERT VALUES (s.sid, s.delta)
WHEN NOT MATCHED THEN
  DO NOTHING;

MERGE works with regular tables, partitioned tables and inheritance
hierarchies, including column and row security enforcement, as well as
support for row and statement triggers and transition tables therein.

MERGE is optimized for OLTP and is parameterizable, though also useful
for large scale ETL/ELT. MERGE is not intended to be used in preference
to existing single SQL commands for INSERT, UPDATE or DELETE since there
is some overhead.  MERGE can be used from PL/pgSQL.

MERGE does not support targetting updatable views or foreign tables, and
RETURNING clauses are not allowed either.  These limitations are likely
fixable with sufficient effort.  Rewrite rules are also not supported,
but it's not clear that we'd want to support them.

Author: Pavan Deolasee <pavan.deolasee@gmail.com>
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Author: Amit Langote <amitlangote09@gmail.com>
Author: Simon Riggs <simon.riggs@enterprisedb.com>
Reviewed-by: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
Reviewed-by: Andres Freund <andres@anarazel.de> (earlier versions)
Reviewed-by: Peter Geoghegan <pg@bowt.ie> (earlier versions)
Reviewed-by: Robert Haas <robertmhaas@gmail.com> (earlier versions)
Reviewed-by: Japin Li <japinli@hotmail.com>
Reviewed-by: Justin Pryzby <pryzby@telsasoft.com>
Reviewed-by: Tomas Vondra <tomas.vondra@enterprisedb.com>
Reviewed-by: Zhihong Yu <zyu@yugabyte.com>
Discussion: https://postgr.es/m/CANP8+jKitBSrB7oTgT9CY2i1ObfOt36z0XMraQc+Xrz8QB0nXA@mail.gmail.com
Discussion: https://postgr.es/m/CAH2-WzkJdBuxj9PO=2QaO9-3h3xGbQPZ34kJH=HukRekwM-GZg@mail.gmail.com
Discussion: https://postgr.es/m/20201231134736.GA25392@alvherre.pgsql
2022-03-28 16:47:48 +02:00
Michael Paquier 6bdf1a1400 Fix collection of typos in the code and the documentation
Some words were duplicated while other places were grammatically
incorrect, including one variable name in the code.

Author: Otto Kekalainen, Justin Pryzby
Discussion: https://postgr.es/m/7DDBEFC5-09B6-4325-B942-B563D1A24BDC@amazon.com
2022-03-15 11:29:35 +09:00
Tom Lane 9240589798 Fix pg_regress to print the correct postmaster address on Windows.
pg_regress reported "Unix socket" as the default location whenever
HAVE_UNIX_SOCKETS is defined.  However, that's not been accurate
on Windows since 8f3ec75de.  Update this logic to match what libpq
actually does now.

This is just cosmetic, but still it's potentially misleading.
Back-patch to v13 where 8f3ec75de came in.

Discussion: https://postgr.es/m/3894060.1646415641@sss.pgh.pa.us
2022-03-04 13:23:58 -05:00
Tom Lane a59c79564b Allow root-owned SSL private keys in libpq, not only the backend.
This change makes libpq apply the same private-key-file ownership
and permissions checks that we have used in the backend since commit
9a83564c5.  Namely, that the private key can be owned by either the
current user or root (with different file permissions allowed in the
two cases).  This allows system-wide management of key files, which
is just as sensible on the client side as the server, particularly
when the client is itself some application daemon.

Sync the comments about this between libpq and the backend, too.

David Steele

Discussion: https://postgr.es/m/f4b7bc55-97ac-9e69-7398-335e212f7743@pgmasters.net
2022-02-28 14:12:52 -05:00
Tom Lane b15f254466 Adjust interaction of libpq pipeline mode with errorMessage resets.
Since commit ffa2e4670, libpq resets conn->errorMessage only when
starting a new query.  However, the later introduction of pipelining
requires a further refinement: the "start of query" isn't necessarily
when it's submitted to PQsendQueryStart.  If we clear at that point
then we risk dropping text for an error that the application has not
noticed yet.  Instead, when queuing a query while a previous query is
still in flight, leave errorMessage alone; reset it when we begin
to process the next query in pqPipelineProcessQueue.

Perhaps this should be back-patched to v14 where ffa2e4670 came in.
However I'm uncertain about whether it interacts with 618c16707.
In the absence of user complaints, leave v14 alone.

Discussion: https://postgr.es/m/1421785.1645723238@sss.pgh.pa.us
2022-02-28 11:31:30 -05:00
Andres Freund 6b04abdfc5 Run tap tests in src/interfaces/libpq.
To be able to run binaries in the test/ directory, prove_[install]check need
to be executable in a single shell invocation, so that test/ can be added to
PATH.

Discussion: https://postgr.es/m/20220223203031.ezrd73ohvjgfksow@alap3.anarazel.de
2022-02-26 16:51:47 -08:00
Andres Freund ac25173cdb Convert src/interfaces/libpq/test to a tap test.
The old form of the test needed a bunch of custom infrastructure. These days
tap tests provide the necessary infrastructure to do better.

We discussed whether to move this test to src/test/modules, alongside
libpq_pipeline, but concluded that the opposite direction would be
better. libpq_pipeline will be moved at a later date, once the buildfarm and
msvc build infrastructure is ready for it.

The invocation of the tap test will be added in the next commit. It involves
just enough buildsystem changes to be worth commiting separately. Can't happen
the other way round because prove errors out when invoked without tests.

Discussion: https://postgr.es/m/20220223203031.ezrd73ohvjgfksow@alap3.anarazel.de
2022-02-26 16:51:47 -08:00
Tom Lane 83a7637e2c Reset conn->errorReported when PQrequestCancel sets errorMessage.
Oversight in commit 618c16707.  This is mainly neatnik-ism, since
if PQrequestCancel is used per its API contract, we should perform
pqClearConnErrorState before reaching any place that would consult
errorReported.  But still, it seems like a bad idea to potentially
leave errorReported pointing past errorMessage.len.
2022-02-20 15:02:41 -05:00
Tom Lane 618c16707a Rearrange libpq's error reporting to avoid duplicated error text.
Since commit ffa2e4670, libpq accumulates text in conn->errorMessage
across a whole query cycle.  In some situations, we may report more
than one error event within a cycle: the easiest case to reach is
where we report a FATAL error message from the server, and then a
bit later we detect loss of connection.  Since, historically, each
error PGresult bears the entire content of conn->errorMessage,
this results in duplication of the FATAL message in any output that
concatenates the contents of the PGresults.

Accumulation in errorMessage still seems like a good idea, especially
in view of the number of places that did ad-hoc error concatenation
before ffa2e4670.  So to fix this, let's track how much of
conn->errorMessage has been read out into error PGresults, and only
include new text in later PGresults.  The tricky part of that is
to be sure that we never discard an error PGresult once made (else
we'd risk dropping some text, a problem much worse than duplication).
While libpq formerly did that in some code paths, a little bit of
rearrangement lets us postpone making an error PGresult at all until
we are about to return it.

A side benefit of that postponement is that it now becomes practical
to return a dummy static PGresult in cases where we hit out-of-memory
while trying to manufacture an error PGresult.  This eliminates the
admittedly-very-rare case where we'd return NULL from PQgetResult,
indicating successful query completion, even though what actually
happened was an OOM failure.

Discussion: https://postgr.es/m/ab4288f8-be5c-57fb-2400-e3e857f53e46@enterprisedb.com
2022-02-18 15:35:21 -05:00
Tom Lane 2e372869aa Don't let libpq PGEVT_CONNRESET callbacks break a PGconn.
As currently implemented, failure of a PGEVT_CONNRESET callback
forces the PGconn into the CONNECTION_BAD state (without closing
the socket, which is inconsistent with other failure paths), and
prevents later callbacks from being called.  This seems highly
questionable, and indeed is questioned by comments in the source.

Instead, let's just ignore the result value of PGEVT_CONNRESET
calls.  Like the preceding commit, this converts event callbacks
into "pure observers" that cannot affect libpq's processing logic.

Discussion: https://postgr.es/m/3185105.1644960083@sss.pgh.pa.us
2022-02-18 11:43:04 -05:00
Tom Lane ce1e7a2f71 Don't let libpq "event" procs break the state of PGresult objects.
As currently implemented, failure of a PGEVT_RESULTCREATE callback
causes the PGresult to be converted to an error result.  This is
intellectually inconsistent (shouldn't a failing callback likewise
prevent creation of the error result? what about side-effects on the
behavior seen by other event procs? why does PQfireResultCreateEvents
act differently from PQgetResult?), but more importantly it destroys
any promises we might wish to make about the behavior of libpq in
nontrivial operating modes, such as pipeline mode.  For example,
it's not possible to promise that PGRES_PIPELINE_SYNC results will
be returned if an event callback fails on those.  With this
definition, expecting applications to behave sanely in the face of
possibly-failing callbacks seems like a very big lift.

Hence, redefine the result of a callback failure as being simply
that that event procedure won't be called any more for this PGresult
(which was true already).  Event procedures can still signal failure
back to the application through out-of-band mechanisms, for example
via their passthrough arguments.

Similarly, don't let failure of a PGEVT_RESULTCOPY callback prevent
PQcopyResult from succeeding.  That definition allowed a misbehaving
event proc to break single-row mode (our sole internal use of
PQcopyResult), and it probably had equally deleterious effects for
outside uses.

Discussion: https://postgr.es/m/3185105.1644960083@sss.pgh.pa.us
2022-02-18 11:37:27 -05:00
Peter Eisentraut 797129e591 Remove IS_AF_UNIX macro
The AF_UNIX macro was being used unprotected by HAVE_UNIX_SOCKETS,
apparently since 2008.  So the redirection through IS_AF_UNIX() is
apparently no longer necessary.  (More generally, all supported
platforms are now HAVE_UNIX_SOCKETS, but even if there were a new
platform in the future, it seems plausible that it would define the
AF_UNIX symbol even without kernel support.)  So remove the
IS_AF_UNIX() macro and make the code a bit more consistent.

Discussion: https://www.postgresql.org/message-id/flat/f2d26815-9832-e333-d52d-72fbc0ade896%40enterprisedb.com
2022-02-15 10:16:34 +01:00
Tom Lane faa189c932 Move libpq's write_failed mechanism down to pqsecure_raw_write().
Commit 1f39a1c06 implemented write-failure postponement in pqSendSome,
which is above SSL/GSS processing.  However, we've now seen failures
indicating that (some versions of?) OpenSSL have a tendency to report
write failures prematurely too.  Hence, move the primary responsibility
for postponing write failures down to pqsecure_raw_write(), below
SSL/GSS processing.  pqSendSome now sets write_failed only in corner
cases where we'd lost the connection already.

A side-effect of this change is that errors detected in the SSL/GSS
layer itself will be reported immediately (as if they were read
errors) rather than being postponed like write errors.  That's
reverting an effect of 1f39a1c06, and I think it's fine: if there's
not a socket-level error, it's hard to be sure whether an OpenSSL
error ought to be considered a read or write failure anyway.

Another important point is that write-failure postponement is now
effective during connection setup.  OpenSSL's misbehavior of this
sort occurs during SSL_connect(), so that's a change we want.

Per bug #17391 from Nazir Bilal Yavuz.  Possibly this should be
back-patched, but I think it prudent to let it age awhile in HEAD
first.

Discussion: https://postgr.es/m/17391-304f81bcf724b58b@postgresql.org
2022-02-12 14:00:09 -05:00
Tom Lane 335fa5a260 Fix thinko in PQisBusy().
In commit 1f39a1c06 I made PQisBusy consider conn->write_failed, but
that is now looking like complete brain fade.  In the first place, the
logic is quite wrong: it ought to be like "and not" rather than "or".
This meant that once we'd gotten into a write_failed state, PQisBusy
would always return true, probably causing the calling application to
iterate its loop until PQconsumeInput returns a hard failure thanks
to connection loss.  That's not what we want: the intended behavior
is to return an error PGresult, which the application probably has
much cleaner support for.

But in the second place, checking write_failed here seems like the
wrong thing anyway.  The idea of the write_failed mechanism is to
postpone handling of a write failure until we've read all we can from
the server; so that flag should not interfere with input-processing
behavior.  (Compare 7247e243a.)  What we *should* check for is
status = CONNECTION_BAD, ie, socket already closed.  (Most places that
close the socket don't touch asyncStatus, but they do reset status.)
This primarily ensures that if PQisBusy() returns true then there is
an open socket, which is assumed by several call sites in our own
code, and probably other applications too.

While at it, fix a nearby thinko in libpq's my_sock_write: we should
only consult errno for res < 0, not res == 0.  This is harmless since
pqsecure_raw_write would force errno to zero in such a case, but it
still could confuse readers.

Noted by Andres Freund.  Backpatch to v12 where 1f39a1c06 came in.

Discussion: https://postgr.es/m/20220211011025.ek7exh6owpzjyudn@alap3.anarazel.de
2022-02-12 13:23:20 -05:00
Tom Lane 1f655fdc39 Fix race condition in gettext() initialization in libpq and ecpglib.
In libpq and ecpglib, multiple threads can concurrently enter the
initialization logic for message localization.  Since we set the
its-done flag before actually doing the work, it'd be possible
for some threads to reach gettext() before anyone has called
bindtextdomain().  Barring bugs in libintl itself, this would not
result in anything worse than failure to localize some early
messages.  Nonetheless, it's a bug, and an easy one to fix.

Noted while investigating bug #17299 from Clemens Zeidler
(much thanks to Liam Bowen for followup investigation on that).
It currently appears that that actually *is* a bug in libintl itself,
but that doesn't let us off the hook for this bit.

Back-patch to all supported versions.

Discussion: https://postgr.es/m/17299-7270741958c0b1ab@postgresql.org
Discussion: https://postgr.es/m/CAE7q7Eit4Eq2=bxce=Fm8HAStECjaXUE=WBQc-sDDcgJQ7s7eg@mail.gmail.com
2022-01-21 15:36:27 -05:00
Tom Lane 5987feb70b Make PQcancel use the PGconn's tcp_user_timeout and keepalives settings.
If connectivity to the server has been lost or become flaky, the
user might well try to send a query cancel.  It's highly annoying
if PQcancel hangs up in such a case, but that's exactly what's likely
to happen.  To ameliorate this problem, apply the PGconn's
tcp_user_timeout and keepalives settings to the TCP connection used
to send the cancel.  This should be safe on Unix machines, since POSIX
specifies that setsockopt() is async-signal-safe.  We are guessing
that WSAIoctl(SIO_KEEPALIVE_VALS) is similarly safe on Windows.
(Note that at least in psql and our other frontend programs, there's
no safety issue involved anyway, since we run PQcancel in its own
thread rather than in a signal handler.)

Most of the value here comes from the expectation that tcp_user_timeout
will be applied as a connection timeout.  That appears to happen on
Linux, even though its tcp(7) man page claims differently.  The
keepalive options probably won't help much, but as long as we can
apply them for not much code, we might as well.

Jelte Fennema, reviewed by Fujii Masao and myself

Discussion: https://postgr.es/m/AM5PR83MB017870DE81FC84D5E21E9D1EF7AA9@AM5PR83MB0178.EURPRD83.prod.outlook.com
2022-01-18 14:13:13 -05:00
Tom Lane f3f467b8f6 Avoid calling strerror[_r] in PQcancel().
PQcancel() is supposed to be safe to call from a signal handler,
and indeed psql uses it that way.  All of the library functions
it uses are specified to be async-signal-safe by POSIX ...
except for strerror.  Neither plain strerror nor strerror_r
are considered safe.  When this code was written, back in the
dark ages, we probably figured "oh, strerror will just index
into a constant array of strings" ... but in any locale except C,
that's unlikely to be true.  Probably the reason we've not heard
complaints is that (a) this error-handling code is unlikely to be
reached in normal use, and (b) in many scenarios, localized error
strings would already have been loaded, after which maybe it's
safe to call strerror here.  Still, this is clearly unacceptable.

The best we can do without relying on strerror is to print the
decimal value of errno, so make it do that instead.  (This is
probably not much loss of user-friendliness, given that it is
hard to get a failure here.)

Back-patch to all supported branches.

Discussion: https://postgr.es/m/2937814.1641960929@sss.pgh.pa.us
2022-01-17 12:52:44 -05:00
Michael Paquier 5513dc6a30 Improve error handling of HMAC computations
This is similar to b69aba7, except that this completes the work for
HMAC with a new routine called pg_hmac_error() that would provide more
context about the type of error that happened during a HMAC computation:
- The fallback HMAC implementation in hmac.c relies on cryptohashes, so
in some code paths it is necessary to return back the error generated by
cryptohashes.
- For the OpenSSL implementation (hmac_openssl.c), the logic is very
similar to cryptohash_openssl.c, where the error context comes from
OpenSSL if one of its internal routines failed, with different error
codes if something internal to hmac_openssl.c failed or was incorrect.

Any in-core code paths that use the centralized HMAC interface are
related to SCRAM, for errors that are unlikely going to happen, with
only SHA-256.  It would be possible to see errors when computing some
HMACs with MD5 for example and OpenSSL FIPS enabled, and this commit
would help in reporting the correct errors but nothing in core uses
that.  So, at the end, no backpatch to v14 is done, at least for now.

Errors in SCRAM related to the computation of the server key, stored
key, etc. need to pass down the potential error context string across
more layers of their respective call stacks for the frontend and the
backend, so each surrounding routine is adapted for this purpose.

Reviewed-by: Sergey Shinderuk
Discussion: https://postgr.es/m/Yd0N9tSAIIkFd+qi@paquier.xyz
2022-01-13 16:17:21 +09:00
Tom Lane 98e93a1fc9 Clean up messy API for src/port/thread.c.
The point of this patch is to reduce inclusion spam by not needing
to #include <netdb.h> or <pwd.h> in port.h (which is read by every
compile in our tree).  To do that, we must remove port.h's
declarations of pqGetpwuid and pqGethostbyname.

pqGethostbyname is only used, and is only ever likely to be used,
in src/port/getaddrinfo.c --- which isn't even built on most
platforms, making pqGethostbyname dead code for most people.
Hence, deal with that by just moving it into getaddrinfo.c.

To clean up pqGetpwuid, invent a couple of simple wrapper
functions with less-messy APIs.  This allows removing some
duplicate error-handling code, too.

In passing, remove thread.c from the MSVC build, since it
contains nothing we use on Windows.

Noted while working on 376ce3e40.

Discussion: https://postgr.es/m/1634252654444.90107@mit.edu
2022-01-11 13:46:20 -05:00
Tom Lane 9cb5518b7f Clean up error message reported after \password encryption failure.
Experimenting with FIPS mode enabled, I saw

regression=# \password joe
Enter new password for user "joe":
Enter it again:
could not encrypt password: disabled for FIPS
out of memory

because PQencryptPasswordConn was still of the opinion that "out of
memory" is always appropriate to print.

Minor oversight in b69aba745.  Like that one, back-patch to v14.
2022-01-11 12:03:06 -05:00
Michael Paquier b69aba7457 Improve error handling of cryptohash computations
The existing cryptohash facility was causing problems in some code paths
related to MD5 (frontend and backend) that relied on the fact that the
only type of error that could happen would be an OOM, as the MD5
implementation used in PostgreSQL ~13 (the in-core implementation is
used when compiling with or without OpenSSL in those older versions),
could fail only under this circumstance.

The new cryptohash facilities can fail for reasons other than OOMs, like
attempting MD5 when FIPS is enabled (upstream OpenSSL allows that up to
1.0.2, Fedora and Photon patch OpenSSL 1.1.1 to allow that), so this
would cause incorrect reports to show up.

This commit extends the cryptohash APIs so as callers of those routines
can fetch more context when an error happens, by using a new routine
called pg_cryptohash_error().  The error states are stored within each
implementation's internal context data, so as it is possible to extend
the logic depending on what's suited for an implementation.  The default
implementation requires few error states, but OpenSSL could report
various issues depending on its internal state so more is needed in
cryptohash_openssl.c, and the code is shaped so as we are always able to
grab the necessary information.

The core code is changed to adapt to the new error routine, painting
more "const" across the call stack where the static errors are stored,
particularly in authentication code paths on variables that provide
log details.  This way, any future changes would warn if attempting to
free these strings.  The MD5 authentication code was also a bit blurry
about the handling of "logdetail" (LOG sent to the postmaster), so
improve the comments related that, while on it.

The origin of the problem is 87ae969, that introduced the centralized
cryptohash facility.  Extra changes are done for pgcrypto in v14 for the
non-OpenSSL code path to cope with the improvements done by this
commit.

Reported-by: Michael Mühlbeyer
Author: Michael Paquier
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/89B7F072-5BBE-4C92-903E-D83E865D9367@trivadis.com
Backpatch-through: 14
2022-01-11 09:55:16 +09:00
Tom Lane 376ce3e404 Prefer $HOME when looking up the current user's home directory.
When we need to identify the home directory on non-Windows, first
consult getenv("HOME").  If that's empty or unset, fall back
on our previous method of checking the <pwd.h> database.

Preferring $HOME allows the user to intentionally point at some
other directory, and it seems to be in line with the behavior of
most other utilities.  However, we shouldn't rely on it completely,
as $HOME is likely to be unset when running as a daemon.

Anders Kaseorg

Discussion: https://postgr.es/m/1634252654444.90107@mit.edu
2022-01-09 19:19:02 -05:00
Bruce Momjian 27b77ecf9f Update copyright for 2022
Backpatch-through: 10
2022-01-07 19:04:57 -05:00
Michael Paquier fb0745fa0d Fix comment in fe-connect.c about PQping and pg_ctl
Since f13ea95f, pg_ctl does not use PQping(), but one comment did not
get the call.

Author: Euler Taveira
Discussion: https://postgr.es/m/4b1deb4a-2771-416d-9710-ccd2fa66f058@www.fastmail.com
2022-01-07 16:05:31 +09:00
Daniel Gustafsson 538724fc36 Extend the private key stat checking error handling
If the stat operation on the private key failed, the code assumed it
was due to an ENOENT, which may or may not be true. Extend the check
by printing a different error message on non-ENOENT errors for easier
debugging.

Per suggestion by Tom Lane due to an issue with the fairywren animal
in the buildfarm.

Discussion: https://postgr.es/m/1632478.1638305700@sss.pgh.pa.us
2021-11-30 23:23:57 +01:00
Peter Eisentraut ee3a1a5b63 Remove check for accept() argument types
This check was used to accommodate a staggering variety in particular
in the type of the third argument of accept().  This is no longer of
concern on currently supported systems.  We can just use socklen_t in
the code and put in a simple check that substitutes int for socklen_t
if it's missing, to cover the few stragglers.

Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://www.postgresql.org/message-id/3538f4c4-1886-64f2-dcff-aaad8267fb82@enterprisedb.com
2021-11-09 15:35:26 +01:00
Tom Lane 160c025880 libpq: reject extraneous data after SSL or GSS encryption handshake.
libpq collects up to a bufferload of data whenever it reads data from
the socket.  When SSL or GSS encryption is requested during startup,
any additional data received with the server's yes-or-no reply
remained in the buffer, and would be treated as already-decrypted data
once the encryption handshake completed.  Thus, a man-in-the-middle
with the ability to inject data into the TCP connection could stuff
some cleartext data into the start of a supposedly encryption-protected
database session.

This could probably be abused to inject faked responses to the
client's first few queries, although other details of libpq's behavior
make that harder than it sounds.  A different line of attack is to
exfiltrate the client's password, or other sensitive data that might
be sent early in the session.  That has been shown to be possible with
a server vulnerable to CVE-2021-23214.

To fix, throw a protocol-violation error if the internal buffer
is not empty after the encryption handshake.

Our thanks to Jacob Champion for reporting this problem.

Security: CVE-2021-23222
2021-11-08 11:14:56 -05:00
Tom Lane 1241fcbd7e Second attempt to silence SSL compile failures on hamerkop.
After further investigation, it seems the cause of the problem
is our recent decision to start defining WIN32_LEAN_AND_MEAN.
That causes <windows.h> to no longer include <wincrypt.h>, which
means that the OpenSSL headers are unable to prevent conflicts
with that header by #undef'ing the conflicting macros.  Apparently,
some other system header that be-secure-openssl.c #includes after
the OpenSSL headers is pulling in <wincrypt.h>.  It's obscure just
where that happens and why we're not seeing it on other Windows
buildfarm animals.  However, it should work to move the OpenSSL
#includes to the end of the list.  For the sake of future-proofing,
do likewise in fe-secure-openssl.c.  In passing, remove useless
double inclusions of <openssl/ssl.h>.

Thanks to Thomas Munro for running down the relevant information.

Discussion: https://postgr.es/m/1051867.1635720347@sss.pgh.pa.us
2021-11-06 12:43:18 -04:00
Daniel Gustafsson de744e9efb Fix check for trapping exit() calls in libpq
Commit e9bc0441f added an errorhint on the exit() check for libpq, but
accidentally changed the nm commandline to use -a instead of -A. These
options are similar enough to hide it in testing, but -a can also show
debugger symbols which isn't what we want. Fix by reverting the check
back to using -A again.

Reported-by: Anton Voloshin <a.voloshin@postgrespro.ru>
Discussion: https://postgr.es/m/bd2c8409-d6b3-5de9-ba0f-40c1381f630f@postgrespro.ru
2021-10-04 21:04:11 +02:00
Daniel Gustafsson e9bc0441f1 Provide error hint on exit() check when building libpq
Commit dc227eb82 introduced a restriction on libpq that no functions which
invoke exit() are allowed to be called. This was further refined and fixed
in e45b0dfa1f and 2f7bae2f92 and 792259591. While this is well documented
in the Makefile, the error message emitted when the check failed was terse,
without hints for new developers without prior context. This adds an error
hint to assist new developers onboarding to postgres.

Author: Rachel Heaton <rheaton@vmware.com>
Co-authored-by: Jacob Champion <pchampion@vmware.com>
Discussion: https://postgr.es/m/CADJcwiVL20955HCNzDqz9BEDr6A77pz6-nac5sbZVvhAEMijLg@mail.gmail.com
2021-10-04 14:32:21 +02:00
Tom Lane 138531f1bb Clear conn->errorMessage at successful completion of PQconnectdb().
Commits ffa2e4670 and 52a10224e caused libpq's connection-establishment
functions to usually leave a nonempty string in the connection's
errorMessage buffer, even after a successful connection.  While that
was intentional on my part, more sober reflection says that it wasn't
a great idea: the string would be a bit confusing.  Also this broke at
least one application that checked for connection success by examining
the errorMessage, instead of using PQstatus() as documented.  Let's
clear the buffer at success exit, restoring the pre-v14 behavior.

Discussion: https://postgr.es/m/4170264.1620321747@sss.pgh.pa.us
2021-09-13 16:53:11 -04:00
Daniel Gustafsson 31f860a52b Set type identifier on BIO
In OpenSSL there are two types of BIO's (I/O abstractions):
source/sink and filters. A source/sink BIO is a source and/or
sink of data, ie one acting on a socket or a file. A filter
BIO takes a stream of input from another BIO and transforms it.
In order for BIO_find_type() to be able to traverse the chain
of BIO's and correctly find all BIO's of a certain type they
shall have the type bit set accordingly, source/sink BIO's
(what PostgreSQL implements) use BIO_TYPE_SOURCE_SINK and
filter BIO's use BIO_TYPE_FILTER. In addition to these, file
descriptor based BIO's should have the descriptor bit set,
BIO_TYPE_DESCRIPTOR.

The PostgreSQL implementation didn't set the type bits, which
went unnoticed for a long time as it's only really relevant
for code auditing the OpenSSL installation, or doing similar
tasks. It is required by the API though, so this fixes it.

Backpatch through 9.6 as this has been wrong for a long time.

Author: Itamar Gafni
Discussion: https://postgr.es/m/SN6PR06MB39665EC10C34BB20956AE4578AF39@SN6PR06MB3966.namprd06.prod.outlook.com
Backpatch-through: 9.6
2021-08-17 14:30:01 +02:00
Daniel Gustafsson 512f4ca6c6 Fix sslsni connparam boolean check
The check for sslsni only checked for existence of the parameter
but not for the actual value of the param.  This meant that the
SNI extension was always turned on.  Fix by inspecting the value
of sslsni and only activate the SNI extension iff sslsni has been
enabled.  Also update the docs to be more in line with how other
boolean params are documented.

Backpatch to 14 where sslsni was first implemented.

Reviewed-by: Tom Lane
Backpatch-through: 14, where sslni was added
2021-08-13 10:32:17 +02:00
Tom Lane 514b4c11d2 Improve libpq's handling of OOM during error message construction.
Commit ffa2e4670 changed libpq so that multiple error reports
occurring during one operation (a connection attempt or query)
are accumulated in conn->errorMessage, where before new ones
usually replaced any prior error.  At least in theory, that makes
us more vulnerable to running out of memory for the errorMessage
buffer.  If it did happen, the user would be left with just an
empty-string error report, which is pretty unhelpful.

We can improve this by relying on pqexpbuffer.c's existing "broken
buffer" convention to track whether we've hit OOM for the current
operation's error string, and then substituting a constant "out of
memory" string in the small number of places where the errorMessage
is read out.

While at it, apply the same method to similar OOM cases in
pqInternalNotice and pqGetErrorNotice3.

Back-patch to v14 where ffa2e4670 came in.  In principle this could
go back further; but in view of the lack of field reports, the
hazard seems negligible in older branches.

Discussion: https://postgr.es/m/530153.1627425648@sss.pgh.pa.us
2021-07-29 13:33:41 -04:00
Michael Paquier 6c9c283166 Install properly fe-auth-sasl.h
The internals of the frontend-side callbacks for SASL are visible in
libpq-int.h, but the header was not getting installed.  This would cause
compilation failures for applications playing with the internals of
libpq.

Issue introduced in 9fd8557.

Author: Mikhail Kulagin
Reviewed-by: Jacob Champion
Discussion: https://postgr.es/m/05ce01d777cb$40f31d60$c2d95820$@postgrespro.ru
2021-07-14 10:37:26 +09:00
Michael Paquier 44bd0126c7 Add more sanity checks in SASL exchanges
The following checks are added, to make the SASL infrastructure more
aware of defects when implementing new mechanisms:
- Detect that no output is generated by a mechanism if an exchange fails
in the backend, failing if there is a message waiting to be sent.
- Handle zero-length messages in the frontend.  The backend handles that
already, and SCRAM would complain if sending empty messages as this is
not authorized for this mechanism, but other mechanisms may want this
capability (the SASL specification allows that).
- Make sure that a mechanism generates a message in the middle of the
exchange in the frontend.

SCRAM, as implemented, respects all these requirements already, and the
recent refactoring of SASL done in 9fd8557 helps in documenting that in
a cleaner way.

Analyzed-by: Jacob Champion
Author: Michael Paquier
Reviewed-by: Jacob Champion
Discussion: https://postgr.es/m/3d2a6f5d50e741117d6baf83eb67ebf1a8a35a11.camel@vmware.com
2021-07-10 21:45:28 +09:00
Alvaro Herrera ab09679429
libpq: Fix sending queries in pipeline aborted state
When sending queries in pipeline mode, we were careless about leaving
the connection in the right state so that PQgetResult would behave
correctly; trying to read further results after sending a query after
having read a result with an error would sometimes hang.  Fix by
ensuring internal libpq state is changed properly.  All the state
changes were being done by the callers of pqAppendCmdQueueEntry(); it
would have become too repetitious to have this logic in each of them, so
instead put it all in that function and relieve callers of the
responsibility.

Add a test to verify this case.  Without the code fix, this new test
hangs sometimes.

Also, document that PQisBusy() would return false when no queries are
pending result.  This is not intuitively obvious, and NULL would be
obtained by calling PQgetResult() at that point, which is confusing.
Wording by Boris Kolpackov.

In passing, fix bogus use of "false" to mean "0", per Ranier Vilela.

Backpatch to 14.

Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Reported-by: Boris Kolpackov <boris@codesynthesis.com>
Discussion: https://postgr.es/m/boris.20210624103805@codesynthesis.com
2021-07-09 15:57:59 -04:00