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082193ef2b
This patch fixes two issues in the ia32 RDRAND assembly code that result in a (possibly significant) loss of entropy. The first, less significant, issue is that, by returning success as 0 from OPENSSL_ia32_rdrand() and OPENSSL_ia32_rdseed(), a subtle bias was introduced. Specifically, because the assembly routine copied the remaining number of retries over the result when RDRAND/RDSEED returned 'successful but zero', a bias towards values 1-8 (primarily 8) was introduced. The second, more worrying issue was that, due to a mixup in registers, when a buffer that was not size 0 or 1 mod 8 was passed to OPENSSL_ia32_rdrand_bytes or OPENSSL_ia32_rdseed_bytes, the last (n mod 8) bytes were all the same value. This issue impacts only the 64-bit variant of the assembly. This change fixes both issues by first eliminating the only use of OPENSSL_ia32_rdrand, replacing it with OPENSSL_ia32_rdrand_bytes, and fixes the register mixup in OPENSSL_ia32_rdrand_bytes. It also adds a sanity test for OPENSSL_ia32_rdrand_bytes and OPENSSL_ia32_rdseed_bytes to help catch problems of this nature in the future. Reviewed-by: Andy Polyakov <appro@openssl.org> Reviewed-by: Rich Salz <rsalz@openssl.org> (Merged from https://github.com/openssl/openssl/pull/5342)
OpenSSL 1.1.1-pre3-dev
Copyright (c) 1998-2018 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
Transport Layer Security (TLS) protocols (including SSLv3) as well as a
full-strength general purpose cryptographic library.
OpenSSL is descended from the SSLeay library developed by Eric A. Young
and Tim J. Hudson. The OpenSSL toolkit is licensed under a dual-license (the
OpenSSL license plus the SSLeay license), which 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 (with platform specific naming):
Provides the client and server-side implementations for SSLv3 and TLS.
libcrypto (with platform specific naming):
Provides general cryptographic and X.509 support needed by SSL/TLS but
not logically part of it.
openssl:
A command line tool that can be used for:
Creation of key parameters
Creation of X.509 certificates, CSRs and CRLs
Calculation of message digests
Encryption and decryption
SSL/TLS client and server tests
Handling of S/MIME signed or encrypted mail
And more...
INSTALLATION
------------
See the appropriate file:
INSTALL Linux, Unix, Windows, OpenVMS, ...
NOTES.* INSTALL addendums for different platforms
SUPPORT
-------
See the OpenSSL website www.openssl.org for details on how to obtain
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If you have any problems with OpenSSL then please take the following steps
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