1=pod
2
3=head1 NAME
4
5d2i_PrivateKey, d2i_PublicKey, d2i_AutoPrivateKey,
6i2d_PrivateKey, i2d_PublicKey,
7d2i_PrivateKey_bio, d2i_PrivateKey_fp
8- decode and encode functions for reading and saving EVP_PKEY structures
9
10=head1 SYNOPSIS
11
12 #include <openssl/evp.h>
13
14 EVP_PKEY *d2i_PrivateKey(int type, EVP_PKEY **a, const unsigned char **pp,
15                          long length);
16 EVP_PKEY *d2i_PublicKey(int type, EVP_PKEY **a, const unsigned char **pp,
17                         long length);
18 EVP_PKEY *d2i_AutoPrivateKey(EVP_PKEY **a, const unsigned char **pp,
19                              long length);
20 int i2d_PrivateKey(EVP_PKEY *a, unsigned char **pp);
21 int i2d_PublicKey(EVP_PKEY *a, unsigned char **pp);
22
23 EVP_PKEY *d2i_PrivateKey_bio(BIO *bp, EVP_PKEY **a);
24 EVP_PKEY *d2i_PrivateKey_fp(FILE *fp, EVP_PKEY **a)
25
26=head1 DESCRIPTION
27
28d2i_PrivateKey() decodes a private key using algorithm B<type>. It attempts to
29use any key specific format or PKCS#8 unencrypted PrivateKeyInfo format. The
30B<type> parameter should be a public key algorithm constant such as
31B<EVP_PKEY_RSA>. An error occurs if the decoded key does not match B<type>.
32d2i_PublicKey() does the same for public keys.
33
34d2i_AutoPrivateKey() is similar to d2i_PrivateKey() except it attempts to
35automatically detect the private key format.
36
37i2d_PrivateKey() encodes B<key>. It uses a key specific format or, if none is
38defined for that key type, PKCS#8 unencrypted PrivateKeyInfo format.
39i2d_PublicKey() does the same for public keys.
40
41These functions are similar to the d2i_X509() functions; see L<d2i_X509(3)>.
42
43=head1 NOTES
44
45All these functions use DER format and unencrypted keys. Applications wishing
46to encrypt or decrypt private keys should use other functions such as
47d2i_PKCS8PrivateKey() instead.
48
49If the B<*a> is not NULL when calling d2i_PrivateKey() or d2i_AutoPrivateKey()
50(i.e. an existing structure is being reused) and the key format is PKCS#8
51then B<*a> will be freed and replaced on a successful call.
52
53=head1 RETURN VALUES
54
55d2i_PrivateKey() and d2i_AutoPrivateKey() return a valid B<EVP_KEY> structure
56or B<NULL> if an error occurs. The error code can be obtained by calling
57L<ERR_get_error(3)>.
58
59i2d_PrivateKey() returns the number of bytes successfully encoded or a
60negative value if an error occurs. The error code can be obtained by calling
61L<ERR_get_error(3)>.
62
63=head1 SEE ALSO
64
65L<crypto(7)>,
66L<d2i_PKCS8PrivateKey_bio(3)>
67
68=head1 COPYRIGHT
69
70Copyright 2017-2018 The OpenSSL Project Authors. All Rights Reserved.
71
72Licensed under the OpenSSL license (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