7 Commits (9ff47ea414c4e6ace347fc4e59866e38b9bbceaf)

Author	SHA1	Message	Date
Michael Paquier	b83dcf7928	Add result size as argument of pg_cryptohash_final() for overflow checks ... With its current design, a careless use of pg_cryptohash_final() could would result in an out-of-bound write in memory as the size of the destination buffer to store the result digest is not known to the cryptohash internals, without the caller knowing about that. This commit adds a new argument to pg_cryptohash_final() to allow such sanity checks, and implements such defenses. The internals of SCRAM for HMAC could be tightened a bit more, but as everything is based on SCRAM_KEY_LEN with uses particular to this code there is no need to complicate its interface more than necessary, and this comes back to the refactoring of HMAC in core. Except that, this minimizes the uses of the existing DIGEST_LENGTH variables, relying instead on sizeof() for the result sizes. In ossp-uuid, this also makes the code more defensive, as it already relied on dce_uuid_t being at least the size of a MD5 digest. This is in philosophy similar to cfc40d3 for base64.c and aef8948 for hex.c. Reported-by: Ranier Vilela Author: Michael Paquier, Ranier Vilela Reviewed-by: Kyotaro Horiguchi Discussion: https://postgr.es/m/CAEudQAoqEGmcff3J4sTSV-R_16Monuz-UpJFbf_dnVH=APr02Q@mail.gmail.com	5 years ago
Michael Paquier	a8ed6bb8f4	Introduce SHA1 implementations in the cryptohash infrastructure ... With this commit, SHA1 goes through the implementation provided by OpenSSL via EVP when building the backend with it, and uses as fallback implementation KAME which was located in pgcrypto and already shaped for an integration with a set of init, update and final routines. Structures and routines have been renamed to make things consistent with the fallback implementations of MD5 and SHA2. uuid-ossp has used for ages a shortcut with pgcrypto to fetch a copy of SHA1 if needed. This was built depending on the build options within ./configure, so this cleans up some code and removes the build dependency between pgcrypto and uuid-ossp. Note that this will help with the refactoring of HMAC, as pgcrypto offers the option to use MD5, SHA1 or SHA2, so only the second option was missing to make that possible. Author: Michael Paquier Reviewed-by: Heikki Linnakangas Discussion: https://postgr.es/m/X9HXKTgrvJvYO7Oh@paquier.xyz	5 years ago
Michael Paquier	55fe26a4b5	Fix allocation logic of cryptohash context data with OpenSSL ... The allocation of the cryptohash context data when building with OpenSSL was happening in the memory context of the caller of pg_cryptohash_create(), which could lead to issues with resowner cleanup if cascading resources are cleaned up on an error. Like other facilities using resowners, move the base allocation to TopMemoryContext to ensure a correct cleanup on failure. The resulting code gets simpler with this commit as the context data is now hold by a unique opaque pointer, so as there is only one single allocation done in TopMemoryContext. After discussion, also change the cryptohash subroutines to return an error if the caller provides NULL for the context data to ease error detection on OOM. Author: Heikki Linnakangas Discussion: https://postgr.es/m/X9xbuEoiU3dlImfa@paquier.xyz	5 years ago
Bruce Momjian	ca3b37487b	Update copyright for 2021 ... Backpatch-through: 9.5	5 years ago
Michael Paquier	9b584953e7	Improve some code around cryptohash functions ... This adjusts some code related to recent changes for cryptohash functions: - Add a variable in md5.h to track down the size of a computed result, moved from pgcrypto. Note that pg_md5_hash() assumed a result of this size already. - Call explicit_bzero() on the hashed data when freeing the context for fallback implementations. For MD5, particularly, it would be annoying to leave some non-zeroed data around. - Clean up some code related to recent changes of uuid-ossp. .gitignore still included md5.c and a comment was incorrect. Discussion: https://postgr.es/m/X9HXKTgrvJvYO7Oh@paquier.xyz	5 years ago
Michael Paquier	b67b57a966	Refactor MD5 implementations according to new cryptohash infrastructure ... This commit heavily reorganizes the MD5 implementations that exist in the tree in various aspects. First, MD5 is added to the list of options available in cryptohash.c and cryptohash_openssl.c. This means that if building with OpenSSL, EVP is used for MD5 instead of the fallback implementation that Postgres had for ages. With the recent refactoring work for cryptohash functions, this change is straight-forward. If not building with OpenSSL, a fallback implementation internal to src/common/ is used. Second, this reduces the number of MD5 implementations present in the tree from two to one, by moving the KAME implementation from pgcrypto to src/common/, and by removing the implementation that existed in src/common/. KAME was already structured with an init/update/final set of routines by pgcrypto (see original pgcrypto/md5.h) for compatibility with OpenSSL, so moving it to src/common/ has proved to be a straight-forward move, requiring no actual manipulation of the internals of each routine. Some benchmarking has not shown any performance gap between both implementations. Similarly to the fallback implementation used for SHA2, the fallback implementation of MD5 is moved to src/common/md5.c with an internal header called md5_int.h for the init, update and final routines. This gets then consumed by cryptohash.c. The original routines used for MD5-hashed passwords are moved to a separate file called md5_common.c, also in src/common/, aimed at being shared between all MD5 implementations as utility routines to keep compatibility with any code relying on them. Like the SHA2 changes, this commit had its round of tests on both Linux and Windows, across all versions of OpenSSL supported on HEAD, with and even without OpenSSL. Author: Michael Paquier Reviewed-by: Daniel Gustafsson Discussion: https://postgr.es/m/20201106073434.GA4961@paquier.xyz	5 years ago
Michael Paquier	87ae9691d2	Move SHA2 routines to a new generic API layer for crypto hashes ... Two new routines to allocate a hash context and to free it are created, as these become necessary for the goal behind this refactoring: switch the all cryptohash implementations for OpenSSL to use EVP (for FIPS and also because upstream does not recommend the use of low-level cryptohash functions for 20 years). Note that OpenSSL hides the internals of cryptohash contexts since 1.1.0, so it is necessary to leave the allocation to OpenSSL itself, explaining the need for those two new routines. This part is going to require more work to properly track hash contexts with resource owners, but this not introduced here. Still, this refactoring makes the move possible. This reduces the number of routines for all SHA2 implementations from twelve (SHA{224,256,386,512} with init, update and final calls) to five (create, free, init, update and final calls) by incorporating the hash type directly into the hash context data. The new cryptohash routines are moved to a new file, called cryptohash.c for the fallback implementations, with SHA2 specifics becoming a part internal to src/common/. OpenSSL specifics are part of cryptohash_openssl.c. This infrastructure is usable for more hash types, like MD5 or HMAC. Any code paths using the internal SHA2 routines are adapted to report correctly errors, which are most of the changes of this commit. The zones mostly impacted are checksum manifests, libpq and SCRAM. Note that e21cbb4 was a first attempt to switch SHA2 to EVP, but it lacked the refactoring needed for libpq, as done here. This patch has been tested on Linux and Windows, with and without OpenSSL, and down to 1.0.1, the oldest version supported on HEAD. Author: Michael Paquier Reviewed-by: Daniel Gustafsson Discussion: https://postgr.es/m/20200924025314.GE7405@paquier.xyz	5 years ago