This reverts commit 3d03b24c3 (Revert Add support for Kerberos credential delegation) which was committed on the grounds of concern about portability, but on further review and discussion, it's clear that we are better off explicitly requiring MIT Kerberos as that appears to be the only GSSAPI library currently that's under proper maintenance and ongoing development. The API used for storing credentials was added to MIT Kerberos over a decade ago while for the other libraries which appear to be mainly based on Heimdal, which exists explicitly to be a re-implementation of MIT Kerberos, the API never made it to a released version (even though it was added to the Heimdal git repo over 5 years ago..). This post-feature-freeze change was approved by the RMT. Discussion: https://postgr.es/m/ZDDO6jaESKaBgej0%40tamriel.snowman.net
This reverts commit 3d4fa227bce4294ce1cc214b4a9d3b7caa3f0454. Per discussion and buildfarm, this depends on APIs that seem to not be available on at least one platform (NetBSD). Should be certainly possible to rework to be optional on that platform if necessary but bit late for that at this point. Discussion: https://postgr.es/m/3286097.1680922218@sss.pgh.pa.us
Support GSSAPI/Kerberos credentials being delegated to the server by a client. With this, a user authenticating to PostgreSQL using Kerberos (GSSAPI) credentials can choose to delegate their credentials to the PostgreSQL server (which can choose to accept them, or not), allowing the server to then use those delegated credentials to connect to another service, such as with postgres_fdw or dblink or theoretically any other service which is able to be authenticated using Kerberos. Both postgres_fdw and dblink are changed to allow non-superuser password-less connections but only when GSSAPI credentials have been delegated to the server by the client and GSSAPI is used to authenticate to the remote system. Authors: Stephen Frost, Peifeng Qiu Reviewed-By: David Christensen Discussion: https://postgr.es/m/CO1PR05MB8023CC2CB575E0FAAD7DF4F8A8E29@CO1PR05MB8023.namprd05.prod.outlook.com
This new libpq function allows the application to send an 'H' message, which instructs the server to flush its outgoing buffer. This hasn't been needed so far because the Sync message already requests a buffer; and I failed to realize that this was needed in pipeline mode because PQpipelineSync also causes the buffer to be flushed. However, sometimes it is useful to request a flush without establishing a synchronization point. Backpatch to 14, where pipeline mode was introduced in libpq. Reported-by: Boris Kolpackov <boris@codesynthesis.com> Author: Álvaro Herrera <alvherre@alvh.no-ip.org> Discussion: https://postgr.es/m/202106252350.t76x73nt643j@alvherre.pgsql
We have a dozen PQset*() functions. PQresultSetInstanceData() and this were the libpq setter functions having a different word order. Adopt the majority word order. Reviewed by Alvaro Herrera and Robert Haas, though this choice of name was not unanimous. Discussion: https://postgr.es/m/20210605060555.GA216695@rfd.leadboat.com
An incorrectly-encoded multibyte character near the end of a string could cause various processing loops to run past the string's terminating NUL, with results ranging from no detectable issue to a program crash, depending on what happens to be in the following memory. This isn't an issue in the server, because we take care to verify the encoding of strings before doing any interesting processing on them. However, that lack of care leaked into client-side code which shouldn't assume that anyone has validated the encoding of its input. Although this is certainly a bug worth fixing, the PG security team elected not to regard it as a security issue, primarily because any untrusted text should be sanitized by PQescapeLiteral or the like before being incorporated into a SQL or psql command. (If an app fails to do so, the same technique can be used to cause SQL injection, with probably much more dire consequences than a mere client-program crash.) Those functions were already made proof against this class of problem, cf CVE-2006-2313. To fix, invent PQmblenBounded() which is like PQmblen() except it won't return more than the number of bytes remaining in the string. In HEAD we can make this a new libpq function, as PQmblen() is. It seems imprudent to change libpq's API in stable branches though, so in the back branches define PQmblenBounded as a macro in the files that need it. (Note that just changing PQmblen's behavior would not be a good idea; notably, it would completely break the escaping functions' defense against this exact problem. So we just want a version for those callers that don't have any better way of handling this issue.) Per private report from houjingyi. Back-patch to all supported branches.
Transform the PQtrace output format from its ancient (and mostly useless) byte-level output format to a logical-message-level output, making it much more usable. This implementation allows the printing code to be written (as it indeed was) by looking at the protocol documentation, which gives more confidence that the three (docs, trace code and actual code) actually match. Author: 岩田 彩 (Aya Iwata) <iwata.aya@fujitsu.com> Reviewed-by: 綱川 貴之 (Takayuki Tsunakawa) <tsunakawa.takay@fujitsu.com> Reviewed-by: Kirk Jamison <k.jamison@fujitsu.com> Reviewed-by: Kyotaro Horiguchi <horikyota.ntt@gmail.com> Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Reviewed-by: 黒田 隼人 (Hayato Kuroda) <kuroda.hayato@fujitsu.com> Reviewed-by: "Nagaura, Ryohei" <nagaura.ryohei@jp.fujitsu.com> Reviewed-by: Ryo Matsumura <matsumura.ryo@fujitsu.com> Reviewed-by: Greg Nancarrow <gregn4422@gmail.com> Reviewed-by: Jim Doty <jdoty@pivotal.io> Reviewed-by: Álvaro Herrera <alvherre@alvh.no-ip.org> Discussion: https://postgr.es/m/71E660EB361DF14299875B198D4CE5423DE3FBA4@g01jpexmbkw25
Pipeline mode in libpq lets an application avoid the Sync messages in the FE/BE protocol that are implicit in the old libpq API after each query. The application can then insert Sync at its leisure with a new libpq function PQpipelineSync. This can lead to substantial reductions in query latency. Co-authored-by: Craig Ringer <craig.ringer@enterprisedb.com> Co-authored-by: Matthieu Garrigues <matthieu.garrigues@gmail.com> Co-authored-by: Álvaro Herrera <alvherre@alvh.no-ip.org> Reviewed-by: Andres Freund <andres@anarazel.de> Reviewed-by: Aya Iwata <iwata.aya@jp.fujitsu.com> Reviewed-by: Daniel Vérité <daniel@manitou-mail.org> Reviewed-by: David G. Johnston <david.g.johnston@gmail.com> Reviewed-by: Justin Pryzby <pryzby@telsasoft.com> Reviewed-by: Kirk Jamison <k.jamison@fujitsu.com> Reviewed-by: Michael Paquier <michael.paquier@gmail.com> Reviewed-by: Nikhil Sontakke <nikhils@2ndquadrant.com> Reviewed-by: Vaishnavi Prabakaran <VaishnaviP@fast.au.fujitsu.com> Reviewed-by: Zhihong Yu <zyu@yugabyte.com> Discussion: https://postgr.es/m/CAMsr+YFUjJytRyV4J-16bEoiZyH=4nj+sQ7JP9ajwz=B4dMMZw@mail.gmail.com Discussion: https://postgr.es/m/CAJkzx4T5E-2cQe3dtv2R78dYFvz+in8PY7A8MArvLhs_pg75gg@mail.gmail.com
libpq's exports.txt was overlooked in commit 36d108761, which the buildfarm is quite unhappy about. Also, I'd gathered that the plan included renaming PQgetSSLKeyPassHook to PQgetSSLKeyPassHook_OpenSSL, but that didn't happen in the patch as committed. I'm taking it on my own authority to do so now, since the window before beta1 is closing fast.
This partially reverts commit 4dc6355210. The information returned by the function can be obtained by calling PQconninfo(), so the function is redundant.