1.\" $OpenBSD: RSA_new.3,v 1.9 2018/04/03 21:20:49 tb Exp $ 2.\" OpenSSL doc/man3/RSA_new.pod 99d63d46 Oct 26 13:56:48 2016 -0400 3.\" OpenSSL doc/crypto/rsa.pod 35d2e327 Jun 3 16:19:49 2016 -0400 4.\" 5.\" This file was written by Ulf Moeller <ulf@openssl.org>. 6.\" Copyright (c) 2000, 2002, 2016 The OpenSSL Project. All rights reserved. 7.\" 8.\" Redistribution and use in source and binary forms, with or without 9.\" modification, are permitted provided that the following conditions 10.\" are met: 11.\" 12.\" 1. Redistributions of source code must retain the above copyright 13.\" notice, this list of conditions and the following disclaimer. 14.\" 15.\" 2. Redistributions in binary form must reproduce the above copyright 16.\" notice, this list of conditions and the following disclaimer in 17.\" the documentation and/or other materials provided with the 18.\" distribution. 19.\" 20.\" 3. All advertising materials mentioning features or use of this 21.\" software must display the following acknowledgment: 22.\" "This product includes software developed by the OpenSSL Project 23.\" for use in the OpenSSL Toolkit. (http://www.openssl.org/)" 24.\" 25.\" 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 26.\" endorse or promote products derived from this software without 27.\" prior written permission. For written permission, please contact 28.\" openssl-core@openssl.org. 29.\" 30.\" 5. Products derived from this software may not be called "OpenSSL" 31.\" nor may "OpenSSL" appear in their names without prior written 32.\" permission of the OpenSSL Project. 33.\" 34.\" 6. Redistributions of any form whatsoever must retain the following 35.\" acknowledgment: 36.\" "This product includes software developed by the OpenSSL Project 37.\" for use in the OpenSSL Toolkit (http://www.openssl.org/)" 38.\" 39.\" THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 40.\" EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 41.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 42.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 43.\" ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 44.\" SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 45.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 46.\" LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 47.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 48.\" STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 49.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 50.\" OF THE POSSIBILITY OF SUCH DAMAGE. 51.\" 52.Dd $Mdocdate: April 3 2018 $ 53.Dt RSA_NEW 3 54.Os 55.Sh NAME 56.Nm RSA_new , 57.Nm RSA_free 58.Nd allocate and free RSA objects 59.Sh SYNOPSIS 60.In openssl/rsa.h 61.Ft RSA * 62.Fn RSA_new void 63.Ft void 64.Fo RSA_free 65.Fa "RSA *rsa" 66.Fc 67.Sh DESCRIPTION 68The RSA functions implement RSA public key encryption and signatures 69as defined in PKCS #1 v2.0 (RFC 2437). 70.Pp 71.Fn RSA_new 72allocates and initializes an 73.Vt RSA 74structure. 75It is equivalent to calling 76.Fn RSA_new_method NULL . 77.Pp 78.Fn RSA_free 79frees the 80.Vt RSA 81structure and its components. 82The key is erased before the memory is returned to the system. 83If 84.Fa rsa 85is a 86.Dv NULL 87pointer, no action occurs. 88.Pp 89The 90.Vt RSA 91structure consists of several 92.Vt BIGNUM 93components. 94It can contain public as well as private RSA keys: 95.Bd -literal 96typedef struct { 97 BIGNUM *n; // public modulus 98 BIGNUM *e; // public exponent 99 BIGNUM *d; // private exponent 100 BIGNUM *p; // secret prime factor 101 BIGNUM *q; // secret prime factor 102 BIGNUM *dmp1; // d mod (p-1) 103 BIGNUM *dmq1; // d mod (q-1) 104 BIGNUM *iqmp; // q^-1 mod p 105 // ... 106} RSA; 107.Ed 108.Pp 109In public keys, the private exponent 110.Fa d 111and the related secret values 112.Fa p , q , dmp1 , dmp2 , 113and 114.Fa iqmp 115are 116.Dv NULL . 117.Pp 118.Fa p , 119.Fa q , 120.Fa dmp1 , 121.Fa dmq1 , 122and 123.Fa iqmp 124may be 125.Dv NULL 126in private keys, but the RSA operations are much faster when these 127values are available. 128.Pp 129Note that RSA keys may use non-standard 130.Vt RSA_METHOD 131implementations, either directly or by the use of 132.Vt ENGINE 133modules. 134In some cases (e.g. an 135.Vt ENGINE 136providing support for hardware-embedded keys), these 137.Vt BIGNUM 138values will not be used by the implementation or may be used for 139alternative data storage. 140For this reason, applications should generally avoid using 141.Vt RSA 142structure elements directly and instead use API functions to query 143or modify keys. 144.Sh RETURN VALUES 145If the allocation fails, 146.Fn RSA_new 147returns 148.Dv NULL 149and sets an error code that can be obtained by 150.Xr ERR_get_error 3 . 151Otherwise it returns a pointer to the newly allocated structure. 152.Sh SEE ALSO 153.Xr BN_new 3 , 154.Xr d2i_RSAPublicKey 3 , 155.Xr DH_new 3 , 156.Xr DSA_new 3 , 157.Xr engine 3 , 158.Xr ERR_get_error 3 , 159.Xr EVP_PKEY_set1_RSA 3 , 160.Xr RSA_blinding_on 3 , 161.Xr RSA_check_key 3 , 162.Xr RSA_generate_key 3 , 163.Xr RSA_get0_key 3 , 164.Xr RSA_get_ex_new_index 3 , 165.Xr RSA_meth_new 3 , 166.Xr RSA_padding_add_PKCS1_type_1 3 , 167.Xr RSA_print 3 , 168.Xr RSA_private_encrypt 3 , 169.Xr RSA_public_encrypt 3 , 170.Xr RSA_set_method 3 , 171.Xr RSA_sign 3 , 172.Xr RSA_sign_ASN1_OCTET_STRING 3 , 173.Xr RSA_size 3 174.Sh STANDARDS 175SSL, PKCS #1 v2.0 176.Pp 177RSA was covered by a US patent which expired in September 2000. 178.Sh HISTORY 179.Fn RSA_new 180and 181.Fn RSA_free 182appeared in SSLeay 0.4 or earlier and have been available since 183.Ox 2.4 . 184