xref: /freebsd/crypto/openssl/doc/man3/RSA_sign.pod (revision 783d3ff6d7fae619db8a7990b8a6387de0c677b5)
1=pod
2
3=head1 NAME
4
5RSA_sign, RSA_verify - RSA signatures
6
7=head1 SYNOPSIS
8
9 #include <openssl/rsa.h>
10
11The following functions have been deprecated since OpenSSL 3.0, and can be
12hidden entirely by defining B<OPENSSL_API_COMPAT> with a suitable version value,
13see L<openssl_user_macros(7)>:
14
15 int RSA_sign(int type, const unsigned char *m, unsigned int m_len,
16              unsigned char *sigret, unsigned int *siglen, RSA *rsa);
17
18 int RSA_verify(int type, const unsigned char *m, unsigned int m_len,
19                unsigned char *sigbuf, unsigned int siglen, RSA *rsa);
20
21=head1 DESCRIPTION
22
23All of the functions described on this page are deprecated.
24Applications should instead use L<EVP_PKEY_sign_init(3)>, L<EVP_PKEY_sign(3)>,
25L<EVP_PKEY_verify_init(3)> and L<EVP_PKEY_verify(3)>.
26
27RSA_sign() signs the message digest B<m> of size B<m_len> using the
28private key B<rsa> using RSASSA-PKCS1-v1_5 as specified in RFC 3447. It
29stores the signature in B<sigret> and the signature size in B<siglen>.
30B<sigret> must point to RSA_size(B<rsa>) bytes of memory.
31Note that PKCS #1 adds meta-data, placing limits on the size of the
32key that can be used.
33See L<RSA_private_encrypt(3)> for lower-level
34operations.
35
36B<type> denotes the message digest algorithm that was used to generate
37B<m>.
38If B<type> is B<NID_md5_sha1>,
39an SSL signature (MD5 and SHA1 message digests with PKCS #1 padding
40and no algorithm identifier) is created.
41
42RSA_verify() verifies that the signature B<sigbuf> of size B<siglen>
43matches a given message digest B<m> of size B<m_len>. B<type> denotes
44the message digest algorithm that was used to generate the signature.
45B<rsa> is the signer's public key.
46
47=head1 RETURN VALUES
48
49RSA_sign() returns 1 on success and 0 for failure.
50RSA_verify() returns 1 on successful verification and 0 for failure.
51
52The error codes can be obtained by L<ERR_get_error(3)>.
53
54=head1 CONFORMING TO
55
56SSL, PKCS #1 v2.0
57
58=head1 SEE ALSO
59
60L<ERR_get_error(3)>,
61L<RSA_private_encrypt(3)>,
62L<RSA_public_decrypt(3)>
63
64=head1 HISTORY
65
66All of these functions were deprecated in OpenSSL 3.0.
67
68=head1 COPYRIGHT
69
70Copyright 2000-2021 The OpenSSL Project Authors. All Rights Reserved.
71
72Licensed under the Apache License 2.0 (the "License").  You may not use
73this file except in compliance with the License.  You can obtain a copy
74in the file LICENSE in the source distribution or at
75L<https://www.openssl.org/source/license.html>.
76
77=cut
78