4 Copyright (c) 1998-2011 The OpenSSL Project
5 Copyright (c) 1995-1998 Eric A. Young, Tim J. Hudson
11 The OpenSSL Project is a collaborative effort to develop a robust,
12 commercial-grade, fully featured, and Open Source toolkit implementing the
13 Secure Sockets Layer (SSL v2/v3) and Transport Layer Security (TLS v1)
14 protocols as well as a full-strength general purpose cryptography library.
15 The project is managed by a worldwide community of volunteers that use the
16 Internet to communicate, plan, and develop the OpenSSL toolkit and its
17 related documentation.
19 OpenSSL is based on the excellent SSLeay library developed from Eric A. Young
20 and Tim J. Hudson. The OpenSSL toolkit is licensed under a dual-license (the
21 OpenSSL license plus the SSLeay license) situation, which basically means
22 that you are free to get and use it for commercial and non-commercial
23 purposes as long as you fulfill the conditions of both licenses.
28 The OpenSSL toolkit includes:
31 Implementation of SSLv2, SSLv3, TLSv1 and the required code to support
32 both SSLv2, SSLv3 and TLSv1 in the one server and client.
35 General encryption and X.509 v1/v3 stuff needed by SSL/TLS but not
36 actually logically part of it. It includes routines for the following:
39 libdes - EAY's libdes DES encryption package which was floating
40 around the net for a few years, and was then relicensed by
41 him as part of SSLeay. It includes 15 'modes/variations'
42 of DES (1, 2 and 3 key versions of ecb, cbc, cfb and ofb;
43 pcbc and a more general form of cfb and ofb) including desx
44 in cbc mode, a fast crypt(3), and routines to read
45 passwords from the keyboard.
47 RC2 encryption - 4 different modes, ecb, cbc, cfb and ofb.
48 Blowfish encryption - 4 different modes, ecb, cbc, cfb and ofb.
49 IDEA encryption - 4 different modes, ecb, cbc, cfb and ofb.
52 MD5 and MD2 message digest algorithms, fast implementations,
53 SHA (SHA-0) and SHA-1 message digest algorithms,
54 MDC2 message digest. A DES based hash that is popular on smart cards.
57 RSA encryption/decryption/generation.
58 There is no limit on the number of bits.
59 DSA encryption/decryption/generation.
60 There is no limit on the number of bits.
61 Diffie-Hellman key-exchange/key generation.
62 There is no limit on the number of bits.
65 X509 encoding/decoding into/from binary ASN1 and a PEM
66 based ASCII-binary encoding which supports encryption with a
67 private key. Program to generate RSA and DSA certificate
68 requests and to generate RSA and DSA certificates.
71 The normal digital envelope routines and base64 encoding. Higher
72 level access to ciphers and digests by name. New ciphers can be
73 loaded at run time. The BIO io system which is a simple non-blocking
74 IO abstraction. Current methods supported are file descriptors,
75 sockets, socket accept, socket connect, memory buffer, buffering, SSL
76 client/server, file pointer, encryption, digest, non-blocking testing
80 A dynamically growing hashing system
82 A Configuration loader that uses a format similar to MS .ini files.
85 A command line tool that can be used for:
86 Creation of RSA, DH and DSA key parameters
87 Creation of X.509 certificates, CSRs and CRLs
88 Calculation of Message Digests
89 Encryption and Decryption with Ciphers
90 SSL/TLS Client and Server Tests
91 Handling of S/MIME signed or encrypted mail
97 Various companies hold various patents for various algorithms in various
98 locations around the world. _YOU_ are responsible for ensuring that your use
99 of any algorithms is legal by checking if there are any patents in your
100 country. The file contains some of the patents that we know about or are
101 rumored to exist. This is not a definitive list.
103 RSA Security holds software patents on the RC5 algorithm. If you
104 intend to use this cipher, you must contact RSA Security for
105 licensing conditions. Their web page is http://www.rsasecurity.com/.
107 RC4 is a trademark of RSA Security, so use of this label should perhaps
108 only be used with RSA Security's permission.
110 The IDEA algorithm is patented by Ascom in Austria, France, Germany, Italy,
111 Japan, the Netherlands, Spain, Sweden, Switzerland, UK and the USA. They
112 should be contacted if that algorithm is to be used; their web page is
113 http://www.ascom.ch/.
115 NTT and Mitsubishi have patents and pending patents on the Camellia
116 algorithm, but allow use at no charge without requiring an explicit
117 licensing agreement: http://info.isl.ntt.co.jp/crypt/eng/info/chiteki.html
122 To install this package under a Unix derivative, read the INSTALL file. For
123 a Win32 platform, read the INSTALL.W32 file. For OpenVMS systems, read
126 Read the documentation in the doc/ directory. It is quite rough, but it
127 lists the functions; you will probably have to look at the code to work out
128 how to use them. Look at the example programs.
133 For some platforms, there are some known problems that may affect the user
134 or application author. We try to collect those in doc/PROBLEMS, with current
135 thoughts on how they should be solved in a future of OpenSSL.
140 See the OpenSSL website www.openssl.org for details of how to obtain
141 commercial technical support.
143 If you have any problems with OpenSSL then please take the following steps
146 - Download the current snapshot from ftp://ftp.openssl.org/snapshot/
147 to see if the problem has already been addressed
148 - Remove ASM versions of libraries
149 - Remove compiler optimisation flags
151 If you wish to report a bug then please include the following information in
155 Self-test report generated by 'make report'
157 OpenSSL version: output of 'openssl version -a'
158 OS Name, Version, Hardware platform
159 Compiler Details (name, version)
160 - Application Details (name, version)
161 - Problem Description (steps that will reproduce the problem, if known)
162 - Stack Traceback (if the application dumps core)
164 Report the bug to the OpenSSL project via the Request Tracker
165 (http://www.openssl.org/support/rt.html) by mail to:
167 openssl-bugs@openssl.org
169 Note that the request tracker should NOT be used for general assistance
170 or support queries. Just because something doesn't work the way you expect
171 does not mean it is necessarily a bug in OpenSSL.
173 Note that mail to openssl-bugs@openssl.org is recorded in the publicly
174 readable request tracker database and is forwarded to a public
175 mailing list. Confidential mail may be sent to openssl-security@openssl.org
176 (PGP key available from the key servers).
178 HOW TO CONTRIBUTE TO OpenSSL
179 ----------------------------
181 Development is coordinated on the openssl-dev mailing list (see
182 http://www.openssl.org for information on subscribing). If you
183 would like to submit a patch, send it to openssl-bugs@openssl.org with
184 the string "[PATCH]" in the subject. Please be sure to include a
185 textual explanation of what your patch does.
187 If you are unsure as to whether a feature will be useful for the general
188 OpenSSL community please discuss it on the openssl-dev mailing list first.
189 Someone may be already working on the same thing or there may be a good
190 reason as to why that feature isn't implemented.
192 Patches should be as up to date as possible, preferably relative to the
193 current Git or the last snapshot. They should follow the coding style of
194 OpenSSL and compile without warnings. Some of the core team developer targets
195 can be used for testing purposes, (debug-steve64, debug-geoff etc). OpenSSL
196 compiles on many varied platforms: try to ensure you only use portable
199 Note: For legal reasons, contributions from the US can be accepted only
200 if a TSU notification and a copy of the patch are sent to crypt@bis.doc.gov
201 (formerly BXA) with a copy to the ENC Encryption Request Coordinator;
202 please take some time to look at
203 http://www.bis.doc.gov/Encryption/PubAvailEncSourceCodeNofify.html [sic]
205 http://w3.access.gpo.gov/bis/ear/pdf/740.pdf (EAR Section 740.13(e))
206 for the details. If "your encryption source code is too large to serve as
207 an email attachment", they are glad to receive it by fax instead; hope you
208 have a cheap long-distance plan.
210 Our preferred format for changes is "diff -u" output. You might
211 generate it like this:
215 # ./Configure dist; make clean
217 # diff -ur openssl-orig openssl-work > mydiffs.patch