openssl/doc/man3/RSA_sign.pod
David Benjamin aa90ca11c9 Make RSA_sign.pod less confusing.
PKCS #1 v2.0 is the name of a document which specifies an algorithm
RSASSA-PKCS1-v1_5, often referred to as "PKCS #1 v1.5" after an earlier
document which specified it. This gets further confusing because the
document PKCS #1 v2.1 specifies two signature algorithms,
RSASSA-PKCS1-v1_5 and RSASSA-PSS. RSA_sign implements RSASSA-PKCS1-v1_5.

Refer to the document using the RFC number which is easier to find
anyway, and refer to the algorithm by its name.

Reviewed-by: Kurt Roeckx <kurt@roeckx.be>
Reviewed-by: Rich Salz <rsalz@openssl.org>

GH: #1474
2016-11-07 21:05:08 +01:00

65 lines
1.9 KiB
Text

=pod
=head1 NAME
RSA_sign, RSA_verify - RSA signatures
=head1 SYNOPSIS
#include <openssl/rsa.h>
int RSA_sign(int type, const unsigned char *m, unsigned int m_len,
unsigned char *sigret, unsigned int *siglen, RSA *rsa);
int RSA_verify(int type, const unsigned char *m, unsigned int m_len,
unsigned char *sigbuf, unsigned int siglen, RSA *rsa);
=head1 DESCRIPTION
RSA_sign() signs the message digest B<m> of size B<m_len> using the
private key B<rsa> using RSASSA-PKCS1-v1_5 as specified in RFC 3447. It
stores the signature in B<sigret> and the signature size in B<siglen>.
B<sigret> must point to RSA_size(B<rsa>) bytes of memory.
Note that PKCS #1 adds meta-data, placing limits on the size of the
key that can be used.
See L<RSA_private_encrypt(3)> for lower-level
operations.
B<type> denotes the message digest algorithm that was used to generate
B<m>.
If B<type> is B<NID_md5_sha1>,
an SSL signature (MD5 and SHA1 message digests with PKCS #1 padding
and no algorithm identifier) is created.
RSA_verify() verifies that the signature B<sigbuf> of size B<siglen>
matches a given message digest B<m> of size B<m_len>. B<type> denotes
the message digest algorithm that was used to generate the signature.
B<rsa> is the signer's public key.
=head1 RETURN VALUES
RSA_sign() returns 1 on success.
RSA_verify() returns 1 on successful verification.
The error codes can be obtained by L<ERR_get_error(3)>.
=head1 CONFORMING TO
SSL, PKCS #1 v2.0
=head1 SEE ALSO
L<ERR_get_error(3)>,
L<RSA_private_encrypt(3)>,
L<RSA_public_decrypt(3)>
=head1 COPYRIGHT
Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved.
Licensed under the OpenSSL license (the "License"). You may not use
this file except in compliance with the License. You can obtain a copy
in the file LICENSE in the source distribution or at
L<https://www.openssl.org/source/license.html>.
=cut