1.\" $OpenBSD: crypto.3,v 1.18 2018/02/27 20:43:41 schwarze Exp $ 2.\" OpenSSL a9c85cea Nov 11 09:33:55 2016 +0100 3.\" 4.\" This file was written by Ulf Moeller <ulf@openssl.org> and 5.\" Dr. Stephen Henson <steve@openssl.org>. 6.\" Copyright (c) 2000, 2002 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: February 27 2018 $ 53.Dt CRYPTO 3 54.Os 55.Sh NAME 56.Nm crypto 57.Nd OpenSSL cryptographic library 58.Sh DESCRIPTION 59The OpenSSL crypto library implements a wide range of cryptographic 60algorithms used in various Internet standards. 61The services provided by this library are used by the OpenSSL 62implementations of TLS and S/MIME, and they have also been used to 63implement SSH, OpenPGP, and other cryptographic standards. 64.Pp 65.Sy Symmetric ciphers 66including AES, Blowfish, CAST, Chacha20, IDEA, DES, RC2, and RC4 67are provided by the generic interface 68.Xr EVP_EncryptInit 3 . 69Low-level stand-alone interfaces include 70.Xr BF_set_key 3 , 71.Xr DES_set_key 3 , 72and 73.Xr RC4 3 . 74.Pp 75.Sy Public key cryptography and key agreement 76are provided by 77.Xr DH_new 3 , 78.Xr DSA_new 3 , 79.Xr ECDSA_SIG_new 3 , 80and 81.Xr RSA_new 3 . 82.Pp 83.Sy Certificates 84are handled by 85.Xr X509_new 3 86and 87.Xr X509v3_add_ext 3 . 88.Pp 89.Sy Authentication codes and hash functions 90offered include 91.Xr HMAC 3 , 92.Xr MD4 3 , 93.Xr MD5 3 , 94.Xr RIPEMD160 3 , 95.Xr SHA1 3 , 96and 97.Xr SHA256 3 . 98.Pp 99.Sy Input, output, and data encoding 100facilities include ASN.1, 101.Xr BIO_new 3 , 102.Xr evp 3 , 103.Xr PEM_read 3 , 104.Xr PKCS7_encrypt 3 , 105.Xr PKCS7_sign 3 , 106.Xr PKCS12_create 3 , 107and 108.Xr SMIME_write_PKCS7 3 . 109.Pp 110.Sy Auxiliary features include: 111.Bl -dash -compact 112.It 113configuration file handling: see 114.Xr OPENSSL_config 3 115.It 116error reporting: see 117.Xr ERR 3 118.It 119thread support: see 120.Xr CRYPTO_set_locking_callback 3 121.It 122.Xr OCSP_REQUEST_new 3 123.El 124.Pp 125.Sy Internal utilities 126include 127.Xr BIO_f_buffer 3 , 128.Xr BN_new 3 , 129.Xr EC_GROUP_new 3 , 130.Xr lh_new 3 . 131.Pp 132Some of the newer functions follow a naming convention using the numbers 133.Sq 0 134and 135.Sq 1 . 136For example consider the names of these functions: 137.Pp 138.Ft int 139.Fo X509_CRL_add0_revoked 140.Fa "X509_CRL *crl" 141.Fa "X509_REVOKED *rev" 142.Fc 143.br 144.Ft int 145.Fo X509_add1_trust_object 146.Fa "X509 *x" 147.Fa "ASN1_OBJECT *obj" 148.Fc 149.Pp 150The 151.Sq 0 152version uses the supplied structure pointer directly in the parent and 153it will be freed up when the parent is freed. 154In the above example 155.Fa crl 156would be freed but 157.Fa rev 158would not. 159.Pp 160The 161.Sq 1 162function uses a copy of the supplied structure pointer (or in some cases 163increases its link count) in the parent and so both 164.Pf ( Fa x 165and 166.Fa obj 167above) should be freed up. 168.Sh SEE ALSO 169.Xr openssl 1 , 170.Xr ssl 3 171