Go to file
Taylor R Campbell 99548cd16e Avoid undefined behaviour with the <ctype.h> functions.
fix https://github.com/openssl/openssl/issues/25112

As defined in the C standard:

   In all cases the argument is an int, the value of which shall
   be representable as an unsigned char or shall equal the value
   of the macro EOF.  If the argument has any other value, the
   behavior is undefined.

This is because they're designed to work with the int values returned
by getc or fgetc; they need extra work to handle a char value.

If EOF is -1 (as it almost always is), with 8-bit bytes, the allowed
inputs to the ctype.h functions are:

   {-1, 0, 1, 2, 3, ..., 255}.

However, on platforms where char is signed, such as x86 with the
usual ABI, code like

   char *p = ...;
   ... isspace(*p) ...

may pass in values in the range:

   {-128, -127, -126, ..., -2, -1, 0, 1, ..., 127}.

This has two problems:

1. Inputs in the set {-128, -127, -126, ..., -2} are forbidden.

2. The non-EOF byte 0xff is conflated with the value EOF = -1, so
   even though the input is not forbidden, it may give the wrong
   answer.

Casting char inputs to unsigned char first works around this, by
mapping the (non-EOF character) range {-128, -127, ..., -1} to {128,
129, ..., 255}, leaving no collisions with EOF.  So the above
fragment needs to be:

   char *p = ...;
   ... isspace((unsigned char)*p) ...

This patch inserts unsigned char casts where necessary.  Most of the
cases I changed, I compile-tested using -Wchar-subscripts -Werror on
NetBSD, which defines the ctype.h functions as macros so that they
trigger the warning when the argument has type char.  The exceptions
are under #ifdef __VMS or #ifdef _WIN32.  I left alone calls where
the input is int where the cast would obviously be wrong; and I left
alone calls where the input is already unsigned char so the cast is
unnecessary.

Reviewed-by: Neil Horman <nhorman@openssl.org>
Reviewed-by: Kurt Roeckx <kurt@roeckx.be>
Reviewed-by: Paul Dale <ppzgs1@gmail.com>
Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/25113)
2024-10-10 20:47:48 +02:00
.ctags.d
.github Revert "TEMPORARY: run daily checks on PR" 2024-10-10 08:26:38 +02:00
apps APPS/storeutl: fix case where uri and outfile are the same 2024-10-09 11:10:19 +02:00
cloudflare-quiche@7ab6a55cfe
Configurations
crypto Avoid undefined behaviour with the <ctype.h> functions. 2024-10-10 20:47:48 +02:00
demos Add SSL_CIPHER_SUITES env variable to quic-hq-interop 2024-10-04 17:42:49 +02:00
dev
doc improve and move text on OPENSSL_TRACE from doc/man1/openssl.pod to doc/man7/openssl-env.pod 2024-10-09 12:11:01 +02:00
engines Avoid undefined behaviour with the <ctype.h> functions. 2024-10-10 20:47:48 +02:00
exporters
external/perl
fuzz
gost-engine@ede3886cc5
include Increase limit for CRL download 2024-10-08 15:59:38 +02:00
krb5@784c38f50e
ms
oqs-provider@0ec51eca39
os-dep
providers Avoid undefined behaviour with the <ctype.h> functions. 2024-10-10 20:47:48 +02:00
pyca-cryptography@7e33b0e773
python-ecdsa@4de8d5bf89
ssl
test APPS/storeutl: fix case where uri and outfile are the same 2024-10-09 11:10:19 +02:00
tlsfuzzer@dbd56c1490
tlslite-ng@771e9f59d6
tools
util check-format-commit: call fewer unneeded processes 2024-10-07 17:50:27 +02:00
VMS
wycheproof@2196000605
.git-blame-ignore-revs Add reformatting commit to .git-blame-ignore-revs 2024-03-11 12:18:03 +00:00
.gitattributes
.gitignore
.gitmodules
ACKNOWLEDGEMENTS.md
AUTHORS.md
build.info
CHANGES.md add news and changes entries for the internal jitter source in FIPS 2024-10-09 13:53:10 +11:00
CODE-OF-CONDUCT.md
config
config.com
configdata.pm.in
Configure Add configuration option to allow the FIPS provider to use the jitter source internally 2024-10-09 13:53:10 +11:00
CONTRIBUTING.md
HACKING.md
INSTALL.md Add configuration option to allow the FIPS provider to use the jitter source internally 2024-10-09 13:53:10 +11:00
LICENSE.txt
NEWS.md add news and changes entries for the internal jitter source in FIPS 2024-10-09 13:53:10 +11:00
NOTES-ANDROID.md Add support in configuration for android-riscv64 2024-02-05 10:08:23 +01:00
NOTES-ANSI.md
NOTES-DJGPP.md
NOTES-NONSTOP.md
NOTES-PERL.md
NOTES-POSIX.md
NOTES-UNIX.md
NOTES-VALGRIND.md
NOTES-VMS.md
NOTES-WINDOWS.md
README-ENGINES.md
README-FIPS.md fips: mention the internal jitter source in the FIPS README 2024-10-09 13:53:10 +11:00
README-PROVIDERS.md
README-QUIC.md
README.md Add interop status badge 2024-09-10 11:38:09 -04:00
SUPPORT.md
VERSION.dat

Welcome to the OpenSSL Project

openssl logo

github actions ci badge Nightly OS Zoo ci badge Provider Compatibility Quic Interop Daily checks

OpenSSL is a robust, commercial-grade, full-featured Open Source Toolkit for the TLS (formerly SSL), DTLS and QUIC (currently client side only) protocols.

The protocol implementations are based on a full-strength general purpose cryptographic library, which can also be used stand-alone. Also included is a cryptographic module validated to conform with FIPS standards.

OpenSSL is descended from the SSLeay library developed by Eric A. Young and Tim J. Hudson.

The official Home Page of the OpenSSL Project is www.openssl.org.

Table of Contents

Overview

The OpenSSL toolkit includes:

  • libssl an implementation of all TLS protocol versions up to TLSv1.3 (RFC 8446), DTLS protocol versions up to DTLSv1.2 (RFC 6347) and the QUIC (currently client side only) version 1 protocol (RFC 9000).

  • libcrypto a full-strength general purpose cryptographic library. It constitutes the basis of the TLS implementation, but can also be used independently.

  • openssl the OpenSSL command line tool, a swiss army knife for cryptographic tasks, testing and analyzing. It 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/DTLS and client and server tests
    • QUIC client tests
    • handling of S/MIME signed or encrypted mail
    • and more...

Download

For Production Use

Source code tarballs of the official releases can be downloaded from www.openssl.org/source. The OpenSSL project does not distribute the toolkit in binary form.

However, for a large variety of operating systems precompiled versions of the OpenSSL toolkit are available. In particular, on Linux and other Unix operating systems, it is normally recommended to link against the precompiled shared libraries provided by the distributor or vendor.

We also maintain a list of third parties that produce OpenSSL binaries for various Operating Systems (including Windows) on the Binaries page on our wiki.

For Testing and Development

Although testing and development could in theory also be done using the source tarballs, having a local copy of the git repository with the entire project history gives you much more insight into the code base.

The official OpenSSL Git Repository is located at git.openssl.org. There is a GitHub mirror of the repository at github.com/openssl/openssl, which is updated automatically from the former on every commit.

A local copy of the Git Repository can be obtained by cloning it from the original OpenSSL repository using

git clone git://git.openssl.org/openssl.git

or from the GitHub mirror using

git clone https://github.com/openssl/openssl.git

If you intend to contribute to OpenSSL, either to fix bugs or contribute new features, you need to fork the OpenSSL repository openssl/openssl on GitHub and clone your public fork instead.

git clone https://github.com/yourname/openssl.git

This is necessary because all development of OpenSSL nowadays is done via GitHub pull requests. For more details, see Contributing.

Build and Install

After obtaining the Source, have a look at the INSTALL file for detailed instructions about building and installing OpenSSL. For some platforms, the installation instructions are amended by a platform specific document.

Specific notes on upgrading to OpenSSL 3.x from previous versions can be found in the ossl-guide-migration(7ossl) manual page.

Documentation

README Files

There are some README.md files in the top level of the source distribution containing additional information on specific topics.

The OpenSSL Guide

There are some tutorial and introductory pages on some important OpenSSL topics within the OpenSSL Guide.

Manual Pages

The manual pages for the master branch and all current stable releases are available online.

Demos

The are numerous source code demos for using various OpenSSL capabilities in the demos subfolder.

Wiki

There is a Wiki at wiki.openssl.org which is currently not very active. It contains a lot of useful information, not all of which is up-to-date.

License

OpenSSL is licensed under the Apache License 2.0, which means that you are free to get and use it for commercial and non-commercial purposes as long as you fulfill its conditions.

See the LICENSE.txt file for more details.

Support

There are various ways to get in touch. The correct channel depends on your requirement. See the SUPPORT file for more details.

Contributing

If you are interested and willing to contribute to the OpenSSL project, please take a look at the CONTRIBUTING file.

Legalities

A number of nations restrict the use or export of cryptography. If you are potentially subject to such restrictions, you should seek legal advice before attempting to develop or distribute cryptographic code.

Copyright

Copyright (c) 1998-2024 The OpenSSL Project Authors

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

All rights reserved.