The EVP library provides a high-level interface to cryptographic func-
tions.
EVP_Seal... and EVP_Open... provide public key encryption and decryp-
tion to implement digital "envelopes".
The EVP_Sign... and EVP_Verify... functions implement digital signa-
tures.
Symmetric encryption is available with the EVP_Encrypt... functions.
The EVP_Digest... functions provide message digests.
Algorithms are loaded with OpenSSL_add_all_algorithms(3).
All the symmetric algorithms (ciphers) and digests can be replaced by
ENGINE modules providing alternative implementations. If ENGINE imple-
mentations of ciphers or digests are registered as defaults, then the
various EVP functions will automatically use those implementations
automatically in preference to built in software implementations. For
more information, consult the engine(3) man page.
Cryptix
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