A compressed stream may end with an empty packet. In this case
decompression finishes before reading the empty packet and the
remaining stream packet causes a failure in reading the following
data. This commit makes sure to consume such extra data, avoiding a
failure when decompression the data. This corner case was reproducible
easily with a data length of 16kB, and existed since e94dd6a. A cheap
regression test is added to cover this case based on a random,
incompressible string.
The first attempt of this patch has allowed to find an older failure
within the compression logic of pgcrypto, fixed by b9b6105. This
involved SLES 15 with z390 where a custom flavor of libz gets used.
Bonus thanks to Mark Wong for providing access to the specific
environment.
Reported-by: Frank Gagnepain
Author: Kyotaro Horiguchi, Michael Paquier
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/16476-692ef7b84e5fb893@postgresql.org
Backpatch-through: 9.5
This reverts commit 9e10898, after finding out that buildfarm members
running SLES 15 on z390 complain on the compression and decompression
logic of the new test: pipistrelles, barbthroat and steamerduck.
Those hosts are visibly using hardware-specific changes to improve zlib
performance, requiring more investigation.
Thanks to Tom Lane for the discussion.
Discussion: https://postgr.es/m/20200722093749.GA2564@paquier.xyz
Backpatch-through: 9.5
A compressed stream may end with an empty packet, and PGP decompression
finished before reading this empty packet in the remaining stream. This
caused a failure in pgcrypto, handling this case as corrupted data.
This commit makes sure to consume such extra data, avoiding a failure
when decompression the entire stream. This corner case was reproducible
with a data length of 16kB, and existed since its introduction in
e94dd6a. A cheap regression test is added to cover this case.
Thanks to Jeff Janes for the extra investigation.
Reported-by: Frank Gagnepain
Author: Kyotaro Horiguchi, Michael Paquier
Discussion: https://postgr.es/m/16476-692ef7b84e5fb893@postgresql.org
Backpatch-through: 9.5
pgp-pubkey-DISABLED test has been unused since 2006, when support for
built-in bignum math was added (commit 1abf76e8). pgp-encrypt-DISABLED has
been unused forever, AFAICS.
Also remove a couple of unused error codes.
pgcrypto already supports key-stretching during symmetric encryption,
including the salted-and-iterated method; but the number of iterations
was not configurable. This commit implements a new s2k-count parameter
to pgp_sym_encrypt() which permits selecting a larger number of
iterations.
Author: Jeff Janes
Certain short salts crashed the backend or disclosed a few bytes of
backend memory. For existing salt-induced error conditions, emit a
message saying as much. Back-patch to 9.0 (all supported versions).
Josh Kupershmidt
Security: CVE-2015-5288
This has been the predominant outcome. When the output of decrypting
with a wrong key coincidentally resembled an OpenPGP packet header,
pgcrypto could instead report "Corrupt data", "Not text data" or
"Unsupported compression algorithm". The distinct "Corrupt data"
message added no value. The latter two error messages misled when the
decrypted payload also exhibited fundamental integrity problems. Worse,
error message variance in other systems has enabled cryptologic attacks;
see RFC 4880 section "14. Security Considerations". Whether these
pgcrypto behaviors are likewise exploitable is unknown.
In passing, document that pgcrypto does not resist side-channel attacks.
Back-patch to 9.0 (all supported versions).
Security: CVE-2015-3167
Most callers pass a stack buffer. The ensuing stack smash can crash the
server, and we have not ruled out the viability of attacks that lead to
privilege escalation. Back-patch to 9.0 (all supported versions).
Marko Tiikkaja
Security: CVE-2015-0243
This fixes a scenario in which pgp_sym_decrypt() failed with "Wrong key
or corrupt data" on messages whose length is 6 less than a power of 2.
Per bug #11905 from Connor Penhale. Fix by Marko Tiikkaja, regression
test case from Jeff Janes.
This add a new pgp_armor_headers function to extract armor headers from an
ASCII-armored blob, and a new overloaded variant of the armor function, for
constructing an ASCII-armor with extra headers.
Marko Tiikkaja and me.
This isn't fully tested as yet, in particular I'm not sure that the
"foo--unpackaged--1.0.sql" scripts are OK. But it's time to get some
buildfarm cycles on it.
sepgsql is not converted to an extension, mainly because it seems to
require a very nonstandard installation process.
Dimitri Fontaine and Tom Lane
about best practice for including the module creation scripts: to wit
that you should suppress NOTICE messages. This avoids creating
regression failures by adding or removing comment lines in the module
scripts.
Few cleanups and couple of new things:
- add SHA2 algorithm to older OpenSSL
- add BIGNUM math to have public-key cryptography work on non-OpenSSL
build.
- gen_random_bytes() function
The status of SHA2 algoritms and public-key encryption can now be
changed to 'always available.'
That makes pgcrypto functionally complete and unless there will be new
editions of AES, SHA2 or OpenPGP standards, there is no major changes
planned.
the pubkey functions a bit. The actual RSA-specific code
there is tiny, most of the patch consists of reorg of the
pubkey code, as lots of it was written as elgamal-only.
---------------------------------------------------------------------------
The SHLIB section was copy-pasted from somewhere and contains
several unnecessary libs. This cleans it up a bit.
-lcrypt
we don't use system crypt()
-lssl, -lssleay32
no SSL here
-lz in win32 section
already added on previous line
-ldes
The chance anybody has it is pretty low.
And the chance pgcrypto works with it is even lower.
Also trim the win32 section.
---------------------------------------------------------------------------
It is already disabled in Makefile, remove code too.
---------------------------------------------------------------------------
I was bit hasty making the random exponent 'k' a prime. Further researh
shows that Elgamal encryption has no specific needs in respect to k,
any random number is fine.
It is bit different for signing, there it needs to be 'relatively prime'
to p - 1, that means GCD(k, p-1) == 1, which is also a lot lighter than
full primality. As we don't do signing, this can be ignored.
This brings major speedup to Elgamal encryption.
---------------------------------------------------------------------------
o pgp_mpi_free: Accept NULLs
o pgp_mpi_cksum: result should be 16bit
o Remove function name from error messages - to be similar to other
SQL functions, and it does not match anyway the called function
o remove couple junk lines
---------------------------------------------------------------------------
o Support for RSA encryption
o Big reorg to better separate generic and algorithm-specific code.
o Regression tests for RSA.
---------------------------------------------------------------------------
o Tom stuck a CVS id into file. I doubt the usefulness of it,
but if it needs to be in the file then rather at the end.
Also tag it as comment for asciidoc.
o Mention bytea vs. text difference
o Couple clarifications
---------------------------------------------------------------------------
There is a choice whether to update it with pgp functions or
remove it. I decided to remove it, updating is pointless.
I've tried to keep the core of pgcrypto relatively independent
from main PostgreSQL, to make it easy to use externally if needed,
and that is good. Eg. that made development of PGP functions much
nicer.
But I have no plans to release it as generic library, so keeping such
doc
up-to-date is waste of time. If anyone is interested in using it in
other products, he can probably bother to read the source too.
Commented source is another thing - I'll try to make another pass
over code to see if there is anything non-obvious that would need
more comments.
---------------------------------------------------------------------------
Marko Kreen
* test error handling
* add tests for des, 3des, cast5
* add some tests to blowfish, rijndael
* Makefile: ability to specify different tests for different crypto
libraries, so we can skip des, 3des and cast5 for builtin.
Marko Kreen
Create objects in public schema.
Make spacing/capitalization consistent.
Remove transaction block use for object creation.
Remove unneeded function GRANTs.
Michael Paquier