Add test case for SCRYPT and rework the code.
* tests/t-kdf.c (check_scrypt): New. (main): Call new test. * configure.ac: Support disabling of the scrypt algorithm. Make KDF enabling similar to the other algorithm classes. Disable scrypt if we don't have a 64 bit type. * cipher/memxor.c, cipher/memxor.h: Remove. * cipher/scrypt.h: Remove. * cipher/kdf-internal.h: New. * cipher/Makefile.am: Remove files. Add new file. Move scrypt.c to EXTRA_libcipher_la_SOURCES. (GCRYPT_MODULES): Add GCRYPT_KDFS. * src/gcrypt.h.in (GCRY_KDF_SCRYPT): Change value. * cipher/kdf.c (pkdf2): Rename to _gcry_kdf_pkdf2. (_gcry_kdf_pkdf2): Don't bail out for SALTLEN==0. (gcry_kdf_derive): Allow for a passwordlen of zero for scrypt. Check for SALTLEN > 0 for GCRY_KDF_PBKDF2. Pass algo to _gcry_kdf_scrypt. (gcry_kdf_derive) [!USE_SCRYPT]: Return an error. * cipher/scrypt.c: Replace memxor.h by bufhelp.h. Replace scrypt.h by kdf-internal.h. Enable code only if HAVE_U64_TYPEDEF is defined. Replace C99 types uint64_t, uint32_t, and uint8_t by libgcrypt types. (_SALSA20_INPUT_LENGTH): Remove underscore from identifier. (_scryptBlockMix): Replace memxor by buf_xor. (_gcry_kdf_scrypt): Use gcry_malloc and gcry_free. Check for integer overflow. Add hack to support blocksize of 1 for tests. Return errors from calls to _gcry_kdf_pkdf2. * cipher/kdf.c (openpgp_s2k): Make static.
This patch prepares the addition of more KDF functions, brings the
code into Libgcrypt shape, adds a test case and makes the code more
robust. For example, scrypt would have fail silently if Libgcrypt was
not build with SHA256 support. Also fixed symbol naming for systems
without a visibility support.
- Signed-off-by: Werner Koch <wk@gnupg.org>