You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
Refactor HMAC implementations
Similarly to the cryptohash implementations, this refactors the existing
HMAC code into a single set of APIs that can be plugged with any crypto
libraries PostgreSQL is built with (only OpenSSL currently). If there
is no such libraries, a fallback implementation is available. Those new
APIs are designed similarly to the existing cryptohash layer, so there
is no real new design here, with the same logic around buffer bound
checks and memory handling.
HMAC has a dependency on cryptohashes, so all the cryptohash types
supported by cryptohash{_openssl}.c can be used with HMAC. This
refactoring is an advantage mainly for SCRAM, that included its own
implementation of HMAC with SHA256 without relying on the existing
crypto libraries even if PostgreSQL was built with their support.
This code has been tested on Windows and Linux, with and without
OpenSSL, across all the versions supported on HEAD from 1.1.1 down to
1.0.1. I have also checked that the implementations are working fine
using some sample results, a custom extension of my own, and doing
cross-checks across different major versions with SCRAM with the client
and the backend.
Author: Michael Paquier
Reviewed-by: Bruce Momjian
Discussion: https://postgr.es/m/X9m0nkEJEzIPXjeZ@paquier.xyz
5 years ago
|
|
|
/*-------------------------------------------------------------------------
|
|
|
|
|
*
|
|
|
|
|
* hmac.h
|
|
|
|
|
* Generic headers for HMAC
|
|
|
|
|
*
|
|
|
|
|
* Portions Copyright (c) 1996-2024, PostgreSQL Global Development Group
|
Refactor HMAC implementations
Similarly to the cryptohash implementations, this refactors the existing
HMAC code into a single set of APIs that can be plugged with any crypto
libraries PostgreSQL is built with (only OpenSSL currently). If there
is no such libraries, a fallback implementation is available. Those new
APIs are designed similarly to the existing cryptohash layer, so there
is no real new design here, with the same logic around buffer bound
checks and memory handling.
HMAC has a dependency on cryptohashes, so all the cryptohash types
supported by cryptohash{_openssl}.c can be used with HMAC. This
refactoring is an advantage mainly for SCRAM, that included its own
implementation of HMAC with SHA256 without relying on the existing
crypto libraries even if PostgreSQL was built with their support.
This code has been tested on Windows and Linux, with and without
OpenSSL, across all the versions supported on HEAD from 1.1.1 down to
1.0.1. I have also checked that the implementations are working fine
using some sample results, a custom extension of my own, and doing
cross-checks across different major versions with SCRAM with the client
and the backend.
Author: Michael Paquier
Reviewed-by: Bruce Momjian
Discussion: https://postgr.es/m/X9m0nkEJEzIPXjeZ@paquier.xyz
5 years ago
|
|
|
* Portions Copyright (c) 1994, Regents of the University of California
|
|
|
|
|
*
|
|
|
|
|
* IDENTIFICATION
|
|
|
|
|
* src/include/common/hmac.h
|
|
|
|
|
*
|
|
|
|
|
*-------------------------------------------------------------------------
|
|
|
|
|
*/
|
|
|
|
|
|
|
|
|
|
#ifndef PG_HMAC_H
|
|
|
|
|
#define PG_HMAC_H
|
|
|
|
|
|
|
|
|
|
#include "common/cryptohash.h"
|
|
|
|
|
|
|
|
|
|
/* opaque context, private to each HMAC implementation */
|
|
|
|
|
typedef struct pg_hmac_ctx pg_hmac_ctx;
|
|
|
|
|
|
|
|
|
|
extern pg_hmac_ctx *pg_hmac_create(pg_cryptohash_type type);
|
|
|
|
|
extern int pg_hmac_init(pg_hmac_ctx *ctx, const uint8 *key, size_t len);
|
|
|
|
|
extern int pg_hmac_update(pg_hmac_ctx *ctx, const uint8 *data, size_t len);
|
|
|
|
|
extern int pg_hmac_final(pg_hmac_ctx *ctx, uint8 *dest, size_t len);
|
|
|
|
|
extern void pg_hmac_free(pg_hmac_ctx *ctx);
|
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
4 years ago
|
|
|
extern const char *pg_hmac_error(pg_hmac_ctx *ctx);
|
Refactor HMAC implementations
Similarly to the cryptohash implementations, this refactors the existing
HMAC code into a single set of APIs that can be plugged with any crypto
libraries PostgreSQL is built with (only OpenSSL currently). If there
is no such libraries, a fallback implementation is available. Those new
APIs are designed similarly to the existing cryptohash layer, so there
is no real new design here, with the same logic around buffer bound
checks and memory handling.
HMAC has a dependency on cryptohashes, so all the cryptohash types
supported by cryptohash{_openssl}.c can be used with HMAC. This
refactoring is an advantage mainly for SCRAM, that included its own
implementation of HMAC with SHA256 without relying on the existing
crypto libraries even if PostgreSQL was built with their support.
This code has been tested on Windows and Linux, with and without
OpenSSL, across all the versions supported on HEAD from 1.1.1 down to
1.0.1. I have also checked that the implementations are working fine
using some sample results, a custom extension of my own, and doing
cross-checks across different major versions with SCRAM with the client
and the backend.
Author: Michael Paquier
Reviewed-by: Bruce Momjian
Discussion: https://postgr.es/m/X9m0nkEJEzIPXjeZ@paquier.xyz
5 years ago
|
|
|
|
|
|
|
|
#endif /* PG_HMAC_H */
|
