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.
60 lines
2.0 KiB
60 lines
2.0 KiB
=pod |
|
|
|
=head1 NAME |
|
|
|
evp - high-level cryptographic functions |
|
|
|
=head1 SYNOPSIS |
|
|
|
#include <openssl/evp.h> |
|
|
|
=head1 DESCRIPTION |
|
|
|
The EVP library provides a high-level interface to cryptographic |
|
functions. |
|
|
|
B<EVP_Seal>I<...> and B<EVP_Open>I<...> provide public key encryption |
|
and decryption to implement digital "envelopes". |
|
|
|
The B<EVP_Sign>I<...> and B<EVP_Verify>I<...> functions implement |
|
digital signatures. |
|
|
|
Symmetric encryption is available with the B<EVP_Encrypt>I<...> |
|
functions. The B<EVP_Digest>I<...> functions provide message digests. |
|
|
|
The B<EVP_PKEY>I<...> functions provide a high level interface to |
|
asymmetric algorithms. |
|
|
|
The L<B<EVP_Encode>I<...>|EVP_EncodeInit(3)> and |
|
L<B<EVP_Decode>I<...>|EVP_EncodeInit(3)> functions implement base 64 encoding |
|
and decoding. |
|
|
|
Algorithms are loaded with OpenSSL_add_all_algorithms(3). |
|
|
|
All the symmetric algorithms (ciphers), digests and asymmetric algorithms |
|
(public key algorithms) can be replaced by ENGINE modules providing alternative |
|
implementations. If ENGINE implementations 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. |
|
|
|
Although low level algorithm specific functions exist for many algorithms |
|
their use is discouraged. They cannot be used with an ENGINE and ENGINE |
|
versions of new algorithms cannot be accessed using the low level functions. |
|
Also makes code harder to adapt to new algorithms and some options are not |
|
cleanly supported at the low level and some operations are more efficient |
|
using the high level interface. |
|
|
|
=head1 SEE ALSO |
|
|
|
L<EVP_DigestInit(3)|EVP_DigestInit(3)>, |
|
L<EVP_EncryptInit(3)|EVP_EncryptInit(3)>, |
|
L<EVP_OpenInit(3)|EVP_OpenInit(3)>, |
|
L<EVP_SealInit(3)|EVP_SealInit(3)>, |
|
L<EVP_SignInit(3)|EVP_SignInit(3)>, |
|
L<EVP_VerifyInit(3)|EVP_VerifyInit(3)>, |
|
L<EVP_EncodeInit(3)>, |
|
L<OpenSSL_add_all_algorithms(3)|OpenSSL_add_all_algorithms(3)>, |
|
L<engine(3)|engine(3)> |
|
|
|
=cut
|
|
|