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 the functions that operate on data in memory update the data pointer I<*pp> 46after a successful operation, just like the other d2i and i2d functions; 47see L<d2i_X509(3)>. 48 49All these functions use DER format and unencrypted keys. Applications wishing 50to encrypt or decrypt private keys should use other functions such as 51d2i_PKCS8PrivateKey() instead. 52 53If the B<*a> is not NULL when calling d2i_PrivateKey() or d2i_AutoPrivateKey() 54(i.e. an existing structure is being reused) and the key format is PKCS#8 55then B<*a> will be freed and replaced on a successful call. 56 57To decode a key with type B<EVP_PKEY_EC>, d2i_PublicKey() requires B<*a> to be 58a non-NULL EVP_PKEY structure assigned an EC_KEY structure referencing the proper 59EC_GROUP. 60 61=head1 RETURN VALUES 62 63The d2i_PrivateKey(), d2i_AutoPrivateKey(), d2i_PrivateKey_bio(), d2i_PrivateKey_fp(), 64and d2i_PublicKey() functions return a valid B<EVP_KEY> structure or B<NULL> if an 65error occurs. The error code can be obtained by calling L<ERR_get_error(3)>. 66 67i2d_PrivateKey() and i2d_PublicKey() return the number of bytes successfully 68encoded or a negative value if an error occurs. The error code can be obtained 69by calling L<ERR_get_error(3)>. 70 71=head1 SEE ALSO 72 73L<crypto(7)>, 74L<d2i_PKCS8PrivateKey_bio(3)> 75 76=head1 COPYRIGHT 77 78Copyright 2017-2021 The OpenSSL Project Authors. All Rights Reserved. 79 80Licensed under the OpenSSL license (the "License"). You may not use 81this file except in compliance with the License. You can obtain a copy 82in the file LICENSE in the source distribution or at 83L<https://www.openssl.org/source/license.html>. 84 85=cut 86