|
|
@ -0,0 +1,144 @@ |
|
|
|
.\" $OpenBSD: sha1.3,v 1.1 1997/07/11 02:05:02 millert Exp $ |
|
|
|
.\" |
|
|
|
.\" Copyright (c) 1997 Todd C. Miller <Todd.Miller@courtesan.com> |
|
|
|
.\" All rights reserved. |
|
|
|
.\" |
|
|
|
.\" Redistribution and use in source and binary forms, with or without |
|
|
|
.\" modification, are permitted provided that the following conditions |
|
|
|
.\" are met: |
|
|
|
.\" 1. Redistributions of source code must retain the above copyright |
|
|
|
.\" notice, this list of conditions and the following disclaimer. |
|
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright |
|
|
|
.\" notice, this list of conditions and the following disclaimer in the |
|
|
|
.\" documentation and/or other materials provided with the distribution. |
|
|
|
.\" 3. All advertising materials mentioning features or use of this software |
|
|
|
.\" must display the following acknowledgement: |
|
|
|
.\" This product includes software developed by Todd C. Miller. |
|
|
|
.\" 4. The name of the author may not be used to endorse or promote products |
|
|
|
.\" derived from this software without specific prior written permission. |
|
|
|
.\" |
|
|
|
.\" THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, |
|
|
|
.\" INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY |
|
|
|
.\" AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL |
|
|
|
.\" THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
|
|
|
.\" EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
|
|
|
.\" PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; |
|
|
|
.\" OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, |
|
|
|
.\" WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR |
|
|
|
.\" OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF |
|
|
|
.\" ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
|
|
|
.\" |
|
|
|
.\" See http://csrc.nist.gov/fips/fip180-1.txt for the detailed standard |
|
|
|
.\" |
|
|
|
.Dd July 10, 1997 |
|
|
|
.Dt SHA1 3 |
|
|
|
.Sh NAME |
|
|
|
.Nm SHA1Init , |
|
|
|
.Nm SHA1Update , |
|
|
|
.Nm SHA1Final , |
|
|
|
.Nm SHA1Transform |
|
|
|
.Nd calculate the NIST Secure Hash Algorithm |
|
|
|
.Sh SYNOPSIS |
|
|
|
.Fd #include <sys/types.h> |
|
|
|
.Fd #include <sha1.h> |
|
|
|
.Ft void |
|
|
|
.Fn SHA1Init "SHA1_CTX *context" |
|
|
|
.Ft void |
|
|
|
.Fn SHA1Update "SHA1_CTX *context" "u_char *data" "u_int len" |
|
|
|
.Ft void |
|
|
|
.Fn SHA1Final "u_char digest[20]" "SHA1_CTX *context" |
|
|
|
.Ft void |
|
|
|
.Fn SHA1Transform "u_int32_t state[5]" "u_char buffer[64]" |
|
|
|
.Sh DESCRIPTION |
|
|
|
The SHA1 functions implement then NIST Secure Hash Algorithm (SHA-1), |
|
|
|
FIPS PUB 180-1. SHA-1 is used to generate a condensed representation |
|
|
|
of a message called a message digest. The algorithm takes a |
|
|
|
message less than 2^64 bits as input and produces a 160-bit digest |
|
|
|
suitable for use as a digital signature. |
|
|
|
.Pp |
|
|
|
The SHA1 functions are considered to be more secure than the |
|
|
|
.Xr md4 3 |
|
|
|
and |
|
|
|
.Xr md5 3 |
|
|
|
functions with which they share a similar interface. |
|
|
|
.Pp |
|
|
|
The |
|
|
|
.Fn SHA1Init |
|
|
|
function initializes a MDX_CTX |
|
|
|
.Ar context |
|
|
|
for use with |
|
|
|
.Fn SHA1Update , |
|
|
|
and |
|
|
|
.Fn SHA1Final . |
|
|
|
The |
|
|
|
.Fn SHA1Update |
|
|
|
function adds |
|
|
|
.Ar data |
|
|
|
of length |
|
|
|
.Ar len |
|
|
|
to the SHA1_CTX specified by |
|
|
|
.Ar context. |
|
|
|
.Fn SHA1Final |
|
|
|
is called when all data has been added via |
|
|
|
.Fn SHA1Update |
|
|
|
and stores a message digest in the |
|
|
|
.Ar digest |
|
|
|
parameter. |
|
|
|
.Pp |
|
|
|
The |
|
|
|
.Fn SHA1Transform |
|
|
|
function is used by |
|
|
|
.Fn SHA1Update |
|
|
|
to hash 512-bit blocks and forms the core of the algorithm. |
|
|
|
Most programs should use the interface provided by |
|
|
|
.Fn SHA1Init , |
|
|
|
.Fn SHA1Update |
|
|
|
and |
|
|
|
.Fn SHA1Final |
|
|
|
instead of calling |
|
|
|
.Fn SHA1Transform |
|
|
|
directly. |
|
|
|
.Sh EXAMPLE |
|
|
|
The follow code fragment will calculate the digest for |
|
|
|
the string "abc" which is ``0xa9993e36476816aba3e25717850c26c9cd0d89d''. |
|
|
|
.Bd -literal -offset indent |
|
|
|
SHA1_CTX sha; |
|
|
|
u_char results[20]; |
|
|
|
char *buf; |
|
|
|
int n; |
|
|
|
|
|
|
|
buf = "abc"; |
|
|
|
n = strlen(buf); |
|
|
|
SHA1Init(&sha); |
|
|
|
SHA1Update(&sha, (u_char *)buf, n); |
|
|
|
SHA1Final(results, &sha); |
|
|
|
|
|
|
|
/* Print the digest as one long hex value */ |
|
|
|
printf("0x"); |
|
|
|
for (n = 0; n < 20; n++) |
|
|
|
printf("%x", results[n]); |
|
|
|
putchar('\n'); |
|
|
|
.Ed |
|
|
|
.Sh CAVEATS |
|
|
|
This implementation of SHA-1 has not been valdiated by NIST |
|
|
|
and as such is not in official compliance with the standard. |
|
|
|
.Pp |
|
|
|
If a message digest is to be copied to a multi-byte type (ie: |
|
|
|
an array of five 32-bit integers) it will be necesary to |
|
|
|
perform byte swapping on little endian machines such as the i386, alpha, |
|
|
|
and vax. |
|
|
|
.Sh AUTHOR |
|
|
|
This implementation of SHA-1 was written by Steve Reid <steve@edmweb.com>. |
|
|
|
.Sh SEE ALSO |
|
|
|
.Xr md4 3 , |
|
|
|
.Xr md5 3 |
|
|
|
.Pp |
|
|
|
.Rs |
|
|
|
.%A J. Burrows |
|
|
|
.%T The Secure Hash Standard |
|
|
|
.%O FIPS PUB 180-1 |
|
|
|
.Re |
|
|
|
.Sh HISTORY |
|
|
|
The SHA-1 functions appeared in |
|
|
|
.Bx Open |
|
|
|
2.0. |