OpenSSL 0.9.5a  1 Apr 2000



 Copyright (c) 1998-2000 The OpenSSL Project

 Copyright (c) 1995-1998 Eric A. Young, Tim J. Hudson

 All rights reserved.



 DESCRIPTION

 -----------



 The OpenSSL Project is a collaborative effort to develop a robust,

 commercial-grade, fully featured, and Open Source toolkit implementing the

 Secure Sockets Layer (SSL v2/v3) and Transport Layer Security (TLS v1)

 protocols as well as a full-strength general purpose cryptography library.

 The project is managed by a worldwide community of volunteers that use the

 Internet to communicate, plan, and develop the OpenSSL toolkit and its

 related documentation. 



 OpenSSL is based on the excellent SSLeay library developed from Eric A. Young

 and Tim J. Hudson.  The OpenSSL toolkit is licensed under a dual-license (the

 OpenSSL license plus the SSLeay license) situation, which basically means

 that you are free to get and use it for commercial and non-commercial

 purposes as long as you fulfill the conditions of both licenses. 



 OVERVIEW

 --------



 The OpenSSL toolkit includes:



 libssl.a:

     Implementation of SSLv2, SSLv3, TLSv1 and the required code to support

     both SSLv2, SSLv3 and TLSv1 in the one server and client.



 libcrypto.a:

     General encryption and X.509 v1/v3 stuff needed by SSL/TLS but not

     actually logically part of it. It includes routines for the following:



     Ciphers

        libdes - EAY's libdes DES encryption package which has been floating

                 around the net for a few years.  It includes 15

                 'modes/variations' of DES (1, 2 and 3 key versions of ecb,

                 cbc, cfb and ofb; pcbc and a more general form of cfb and

                 ofb) including desx in cbc mode, a fast crypt(3), and

                 routines to read passwords from the keyboard.

        RC4 encryption,

        RC2 encryption      - 4 different modes, ecb, cbc, cfb and ofb.

        Blowfish encryption - 4 different modes, ecb, cbc, cfb and ofb.

        IDEA encryption     - 4 different modes, ecb, cbc, cfb and ofb.



     Digests

        MD5 and MD2 message digest algorithms, fast implementations,

        SHA (SHA-0) and SHA-1 message digest algorithms,

        MDC2 message digest. A DES based hash that is popular on smart cards.



     Public Key

        RSA encryption/decryption/generation.  

            There is no limit on the number of bits.

        DSA encryption/decryption/generation.   

            There is no limit on the number of bits.

        Diffie-Hellman key-exchange/key generation.  

            There is no limit on the number of bits.



     X.509v3 certificates

        X509 encoding/decoding into/from binary ASN1 and a PEM

             based ascii-binary encoding which supports encryption with a

             private key.  Program to generate RSA and DSA certificate

             requests and to generate RSA and DSA certificates.



     Systems

        The normal digital envelope routines and base64 encoding.  Higher

        level access to ciphers and digests by name.  New ciphers can be

        loaded at run time.  The BIO io system which is a simple non-blocking

        IO abstraction.  Current methods supported are file descriptors,

        sockets, socket accept, socket connect, memory buffer, buffering, SSL

        client/server, file pointer, encryption, digest, non-blocking testing

        and null.



     Data structures

        A dynamically growing hashing system

        A simple stack.

        A Configuration loader that uses a format similar to MS .ini files.



 openssl: 

     A command line tool that can be used for:

        Creation of RSA, DH and DSA key parameters

        Creation of X.509 certificates, CSRs and CRLs 

        Calculation of Message Digests

        Encryption and Decryption with Ciphers

        SSL/TLS Client and Server Tests

        Handling of S/MIME signed or encrypted mail



        

 PATENTS

 -------



 Various companies hold various patents for various algorithms in various

 locations around the world. _YOU_ are responsible for ensuring that your use

 of any algorithms is legal by checking if there are any patents in your

 country.  The file contains some of the patents that we know about or are

 rumoured to exist. This is not a definitive list.



 RSA Data Security holds software patents on the RSA and RC5 algorithms.  If

 their ciphers are used used inside the USA (and Japan?), you must contact RSA

 Data Security for licensing conditions. Their web page is

 http://www.rsa.com/.



 RC4 is a trademark of RSA Data Security, so use of this label should perhaps

 only be used with RSA Data Security's permission. 



 The IDEA algorithm is patented by Ascom in Austria, France, Germany, Italy,

 Japan, Netherlands, Spain, Sweden, Switzerland, UK and the USA.  They should

 be contacted if that algorithm is to be used, their web page is

 http://www.ascom.ch/.



 INSTALLATION

 ------------



 To install this package under a Unix derivative, read the INSTALL file.  For

 a Win32 platform, read the INSTALL.W32 file.  For OpenVMS systems, read

 INSTALL.VMS.



 For people in the USA, it is possible to compile OpenSSL to use RSA Inc.'s

 public key library, RSAREF, by configuring OpenSSL with the option "rsaref".



 Read the documentation in the doc/ directory.  It is quite rough, but it

 lists the functions, you will probably have to look at the code to work out

 how to used them. Look at the example programs.



 SUPPORT 

 -------



 If you have any problems with OpenSSL then please take the following steps

 first:



    - Download the current snapshot from ftp://ftp.openssl.org/snapshot/

      to see if the problem has already been addressed

    - Remove ASM versions of libraries

    - Remove compiler optimisation flags 



 If you wish to report a bug then please include the following information in

 any bug report:



    - On Unix systems:

        Self-test report generated by 'make report'

    - On other systems:

        OpenSSL version: output of 'openssl version -a'

        OS Name, Version, Hardware platform

        Compiler Details (name, version)

    - Application Details (name, version)

    - Problem Description (steps that will reproduce the problem, if known)

    - Stack Traceback (if the application dumps core)



 Report the bug to the OpenSSL project at:



    openssl-bugs@openssl.org



 Note that mail to openssl-bugs@openssl.org is forwarded to a public

 mailing list. Confidential mail may be sent to openssl-security@openssl.org

 (PGP key available from the key servers).



 HOW TO CONTRIBUTE TO OpenSSL

 ----------------------------



 Development is coordinated on the openssl-dev mailing list (see

 http://www.openssl.org for information on subscribing). If you

 would like to submit a patch, send it to openssl-dev@openssl.org with

 the string "[PATCH]" in the subject. Please be sure to include a

 textual explanation of what your patch does.



 The preferred format for changes is "diff -u" output. You might

 generate it like this:



 # cd openssl-work

 # [your changes]

 # ./Configure dist; make clean

 # cd ..

 # diff -urN openssl-orig openssl-work > mydiffs.patch