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.\" ======================================================================
.\"
.IX Title "evp 3"
.TH evp 3 "0.9.7b" "2002-08-06" "OpenSSL"
.UC
.SH "NAME"
evp \- high-level cryptographic functions
.SH "LIBRARY"
libcrypto, -lcrypto
.SH "SYNOPSIS"
.IX Header "SYNOPSIS"
.Vb 1
\& #include <openssl/evp.h>
.Ve
.SH "DESCRIPTION"
.IX Header "DESCRIPTION"
The \s-1EVP\s0 library provides a high-level interface to cryptographic
functions.
.PP
\&\fBEVP_Seal\fR\fI...\fR and \fBEVP_Open\fR\fI...\fR provide public key encryption
and decryption to implement digital \*(L"envelopes\*(R".
.PP
The \fBEVP_Sign\fR\fI...\fR and \fBEVP_Verify\fR\fI...\fR functions implement
digital signatures.
.PP
Symmetric encryption is available with the \fBEVP_Encrypt\fR\fI...\fR
functions.  The \fBEVP_Digest\fR\fI...\fR functions provide message digests.
.PP
Algorithms are loaded with \fIOpenSSL_add_all_algorithms\fR\|(3).
.PP
All the symmetric algorithms (ciphers) and digests can be replaced by \s-1ENGINE\s0
modules providing alternative implementations. If \s-1ENGINE\s0 implementations of
ciphers or digests are registered as defaults, then the various \s-1EVP\s0 functions
will automatically use those implementations automatically in preference to
built in software implementations. For more information, consult the \fIengine\fR\|(3)
man page.
.SH "SEE ALSO"
.IX Header "SEE ALSO"
EVP_DigestInit(3),
EVP_EncryptInit(3),
EVP_OpenInit(3),
EVP_SealInit(3),
EVP_SignInit(3),
EVP_VerifyInit(3),
OpenSSL_add_all_algorithms(3),
engine(3)