Aaron Gifford's Implementations of SHA-1, SHA-224, SHA-256, SHA-384, and SHA-512Secure Hash Algorithm (SHA)
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SHA-1, SHA-224, SHA-256, SHA-384, and SHA-512
NEW 07 JANUARY 2004 Read on below for information about the 1.1 version that includes SHA-1, SHA-224 functionality.
Here's my open source implementation of the SHA-1, SHA-224, SHA-256, SHA-384, and SHA-512 secure has algorithms. It's released under an open source BSD license. The README contained in the tarball below is included later on this page. The tarball contains seven files, the README file, the SHA-1/224/256/384/512 implementation in two files, sha2.c and sha2.h, and several utility programs, sha2test.pl and mktestdata.pl (two perl scripts for testing to make sure the library is working correctly and comparing with known test vectors), sha2speed.c (to test how fast the implementation is working), and sha2prog.c, a utility that uses the library to generate SHA-224, SHA-256, SHA-384, and SHA-512 hashes from either standard input, or from a file.
HMAC-SHA1: Before writing my SHA implementations, I wrote an implementation of the HMAC-SHA1 algorithm (it includes Steve Reid's public domain SHA1 implementation since I wrote it before adding SHA-1 to my own library). I wrote it initially as part of a demonstration of Prof. Ron Rivest's Chaffing and Winnowing technique. One evening I dredged up the old code and cleaned a few things up and tarred and gzipped it. My code is released under a BSD-style open source license, while my changes to Steve Reid's SHA1 code are in the public domain (as his code is). If you have an SHA-1 implementation in a library, you can use that instead (or have it use my SHA-1implementation). There's no documentation except in the source files themselves. It was compiled and tested quite some time ago under FreeBSD 4.0 and on Linux (at roughly the same time FreeBSD 4.0 was relatively new). Thanks to Compaq (now HP), and their multi-platform test-drive site, it's even been built and minimally tested on Compaq's Tru64 Unix running on Intel platforms and Compaq Alphas. I make no guarantees about the accuracy, usefulness, or anything else of the code. Use at your own risk.
The current stable (and fairly well tested) version of SHA-256/384/512 is version 1.0.1, but it does not include SHA-1 or SHA-224 functionality.
The latest version is 1.1 adds SHA-1 and SHA-224 functionality. However, the new version does consolidate the SHAxxx_CTX data structure into a single SHA_CTX structure (union), which means a minor, quick edit to anything interfacing with the implementation using the 1.0 style interface. Be aware that SHA-1 is considered broken and may not be appropriate in some applications.
A subdirectory with 20 test vectors is included. The perl scripts can be used (at least on FreeBSD systems they work) to make sure that the program is working correctly. Included are the NIST test vectors, as well as several that other implementors have shared with me, or I've found on the Internet. I have also included some of my own. So far, this implementation appears to agree with output from other versions I've encountered.
Thank you, David Ireland for your additional vectors. Thanks also to Stefek Zaba, whose SHA256 implementation in POP11 appears to agree with my C implementation. Thanks to Tom St Dennis for some additional test vectors, including some SHA-224 vectors.
Thank you, Rogier van de Pol, for exposing the off-by-one flaw in my beta implementation in versions earlier than 1.0 RELEASE.
Thanks to Stephane Leon for noting that "MEMSET_BZERO(context, sizeof(context))" emits warnings in some Clang versions. I've updated the code to do "MEMSET_BZERO(context, sizeof(SHA_CTX))" instead.
Thanks to rvkisley for pointing out a problem in the perl test script (and suggesting a fix).
Download the latest stable (well tested) version: 1.0.1 (RELEASE)
Download the latest untested ALPHA version that includes SHA-224: 1.1.1 ALPHA
If you have access to a machine with big endian architecture and you have some spare time to blow, I would appreciate hearing from you about how or if this implemention works, particularly the new 1.1.1 ALPHA version.. If you do email me, please let me know what version you tested.
Thanks to Jun-ichiro itojun Hagino for several suggestions, including the suggested change to use u_intXX_t types since most BSD-based systems support them (and Linux x86 apparently does too, at least on the Debian box I tested the implementation on). Thanks also to those who compiled and tested the version and emailed me.
See NIST's Secure Hash Standard web site. That page links to the PDF document describing the algorithms. Several of the test vectors used by the sha2test program were taken from this document.
See NIST's FIPS 180-2 SECURE HASH STANDARD CHANGE NOTICE for preliminary information about SHA-224.
As of winter 2005, SHA-1 is considered broken. Read Bruce Schneier's blog entry about it for additional information. My library will still include SHA-1, but it is recommended that you not use it.The below text is from the version 1.1 README file:
VERSION: This is version 1.1.1 ALPHA Ignore the next RCS version line, please. Thanks. $Id: README,v 1.2 2004/01/05 09:51:12 adg Exp $ The 1.0 RELEASE (the previous version) appears to be quite stable and has been used in quite a few places. This new ALPHA version adds SHA-224 functionality, updates the perl scripts for doing test vectors, consolidates the various SHAxxx_CTX structures into a single union SHA2_CTX, and consolidates a tiny bit of code. The bulk of the hashing program is unchanged, however. And other than the consolidation of the data structure, the interface is identical. This release is ALPHA because I have not yet done testing on any other platforms. I will be testing it on MAX OS X (big endian) soon. I welcome other platform tests to work out portability bugs that may have been introduced. I also welcome reports of issues with the new test vector perl script changes. The SHA-224 implementation appears to agree with those of other folks who have posted test data on the web (as of 05 JAN 2004), the very few test vectors I was able to find. LICENSE: This implementation is released under an OPEN SOURCE BSD license. WHAT IT IS: The files sha2.h and sha2.c implement the SHA-224, SHA-256, SHA-384, and SHA-512 hash algorithms as described in the PDF documents found at the http://csrc.nist.gov/cryptval/shs/sha256-384-512.pdf http://csrc.nist.gov/publications/fips/fips180-2/FIPS180-2_changenotice.pdf The interface is similar to the interface to SHA-1 found in the OpenSSL library. The file sha2prog.c is a simple program that accepts input from either STDIN or reads one or more files specified on the command line, and then generates the specified hash (either SHA-224, SHA-256, SHA-384, SHA-512, any combination thereof, or all four hashes at once). LIMITATIONS: This implementation has several limitations: * Input data is only accepted in octet-length increments. No sub-byte data is handled. The NIST document describes how to handle sub-byte input data, but for ease of implementation this version will only accept message data in multiples of bytes. * This implementation utilizes 64-bit integer data types. If your system and compiler does not have a 64-bit integer data type, this implementation will not work. * Because of the use of 64-bit operations, many 32-bit architectures that do have 64-bit data types but do operations most efficiently on 32-bit words, this implementation may be slower than an implementation designed to use only 32-bit words (emulating the 64-bit operations). * On platforms with 128-bit integer data types, the SHA-384 and SHA-512 bit counters used by this implementation might be better off using the 128-bit type instead of simulating it with two 64-bit integers. * This implementation was written in C in hopes of portability and for the fun of it during my spare time. It is probably not the most efficient or fastest C implementation. I welcome suggestions, how to speed things up without breaking portability, as well as suggestions to improve portability. BEFORE YOU COMPILE (OPTIONS): Each of the options described below may either be defined in the sha2.h header file (or in the sha2.c file in some cases), or on the command line at compile time if your compiler supports such things. For example: #define SHA2_USE_INTTYPES_H #define SHA2_UNROLL_TRANSFORM Or: cc -c -DSHA2_UNROLL_TRANSFORM sha2.c cc -c -DBYTE_ORDER=4321 -DBIG_ENDIAN=4321 sha2.c Here are the available options. Read on below for a description of each one: SHA2_USE_INTTYPES_H SHA2_USE_MEMSET_MEMCPY/SHA2_USE_BZERO_BCOPY SHA2_UNROLL_TRANSFORM BYTE_ORDER (LITTLE_ENDIAN/BIG_ENDIAN) * SHA2_USE_INTTYPES_H option: By default, this code uses u_intXX_t data types for 8 bit, 32 bit, and 64 bit unsigned integer type definitions. Most BSD systems define these, as does Linux. However, some (like Compaq's Tru64 Unix) may instead use uintXX_t data types as defined by recent ANSI C standards and as included in the inttypes.h header file. Those wanting to use inttypes.h need to define this either in sha.h or at compile time. On those systems where NEITHER definitions are available, you will need to edit both sha2.h and sha2.c and define things by hand in the appropriate sections. * BYTE_ORDER definitions: This code assumes that BYTE_ORDER will be defined by the system during compile to either equal LITTLE_ENDIAN or BIG_ENDIAN. If your system does not define these, you may need to define them by hand in the sha.c file according to the byte ordering conventions of your system. * SHA2_USE_MEMSET_MEMCPY or SHA2_USE_BZERO_BCOPY The code in sha2.c can use either memset()/memcpy() for memory block operations, or bzero()/mcopy(). If you define neither of these, the code will default to memset()/memcpy(). You can define either at the command line or in sha2.h or in sha2.c. * SHA2_UNROLL_TRANSFORM By defining this either on the command line or in sha2.h or sha2.c, the code will use macros to partially "unroll" the SHA transform function. This usually generates bigger executables. It CAN (but not necessarily WILL) generate faster code when you tell your compiler to optimize things. For example, on the FreeBSD and Linux x86 systems I tested things on (using gcc), when I optimized with just -O2 and unrolled the transform, the hash transform was faster by 15-30%. On these same systems, if I did NO optimization, the unrolled transform was SLOWER, much slower (I'm guessing because the code was breaking the cache, but I'm not sure). Your mileage may vary. PORTABILITY: The code in sha2.c and sha2.h is intended to be portable. It may require that you do a few #definitions in the .h file. I've successfully compiled and tested the sha2.c and sha2.h code on Apple's OS X (on a PPC), FreeBSD 4.1.1 on Intel, Linux on Intel, FreeBSD on the Alpha, and even under Windows98SE using Metrowerks C. The utility/example programs (sha2prog.c, sha2test.c, and sha2speed.c) will very likely have more trouble in portability since they do I/O. To get sha2.c/sha2.h working under Windows, I had to define SHA2_USE_INTTYPES_H, BYTE_ORDER, LITTLE_ENDIAN, and had to comment out the include of