226 lines
6.1 KiB
Groff
226 lines
6.1 KiB
Groff
.\" $NetBSD: rmd160.3,v 1.2 2000/12/11 18:57:46 ad Exp $
|
|
.\" $OpenBSD: rmd160.3,v 1.12 2000/04/18 03:01:29 aaron 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. 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://www.esat.kuleuven.ac.be/~bosselae/ripemd160.html
|
|
.\" for detailed information about RIPEMD-160.
|
|
.\"
|
|
.Dd July 16, 1997
|
|
.Dt RMD160 3
|
|
.Os
|
|
.Sh NAME
|
|
.Nm RMD160Init ,
|
|
.Nm RMD160Update ,
|
|
.Nm RMD160Final ,
|
|
.Nm RMD160Transform ,
|
|
.Nm RMD160End ,
|
|
.Nm RMD160File ,
|
|
.Nm RMD160Data
|
|
.Nd calculate the ``RIPEMD-160'' message digest
|
|
.Sh SYNOPSIS
|
|
.Fd #include <sys/types.h>
|
|
.Fd #include <rmd160.h>
|
|
.Ft void
|
|
.Fn RMD160Init "RMD160_CTX *context"
|
|
.Ft void
|
|
.Fn RMD160Update "RMD160_CTX *context" "const u_char *data" "u_int nbytes"
|
|
.Ft void
|
|
.Fn RMD160Final "u_char digest[20]" "RMD160_CTX *context"
|
|
.Ft void
|
|
.Fn RMD160Transform "u_int32_t state[5]" "const u_int32_t block[16]"
|
|
.Ft "char *"
|
|
.Fn RMD160End "RMD160_CTX *context" "char *buf"
|
|
.Ft "char *"
|
|
.Fn RMD160File "char *filename" "char *buf"
|
|
.Ft "char *"
|
|
.Fn RMD160Data "u_char *data" "size_t len" "char *buf"
|
|
.Sh DESCRIPTION
|
|
The RMD160 functions implement the 160-bit RIPE message digest hash algorithm
|
|
(RMD-160).
|
|
RMD-160 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 RMD160 functions are considered to be more secure than the
|
|
.Xr md4 3
|
|
and
|
|
.Xr md5 3
|
|
functions and at least as secure as the
|
|
.Xr sha1 3
|
|
function.
|
|
All share a similar interface.
|
|
.Pp
|
|
The
|
|
.Fn RMD160Init
|
|
function initializes a RMD160_CTX
|
|
.Ar context
|
|
for use with
|
|
.Fn RMD160Update ,
|
|
and
|
|
.Fn RMD160Final .
|
|
The
|
|
.Fn RMD160Update
|
|
function adds
|
|
.Ar data
|
|
of length
|
|
.Ar nbytes
|
|
to the RMD160_CTX specified by
|
|
.Ar context .
|
|
.Fn RMD160Final
|
|
is called when all data has been added via
|
|
.Fn RMD160Update
|
|
and stores a message digest in the
|
|
.Ar digest
|
|
parameter.
|
|
When a null pointer is passed to
|
|
.Fn RMD160Final
|
|
as first argument only the final padding will be applied and the
|
|
current context can still be used with
|
|
.Fn RMD160Update .
|
|
.Pp
|
|
The
|
|
.Fn RMD160Transform
|
|
function is used by
|
|
.Fn RMD160Update
|
|
to hash 512-bit blocks and forms the core of the algorithm.
|
|
Most programs should use the interface provided by
|
|
.Fn RMD160Init ,
|
|
.Fn RMD160Update
|
|
and
|
|
.Fn RMD160Final
|
|
instead of calling
|
|
.Fn RMD160Transform
|
|
directly.
|
|
.Pp
|
|
The
|
|
.Fn RMD160End
|
|
function is a front end for
|
|
.Fn RMD160Final
|
|
which converts the digest into an
|
|
.Tn ASCII
|
|
representation of the 160 bit digest in hexadecimal.
|
|
.Pp
|
|
The
|
|
.Fn RMD160File
|
|
function calculates the digest for a file and returns the result via
|
|
.Fn RMD160End .
|
|
If
|
|
.Fn RMD160File
|
|
is unable to open the file a NULL pointer is returned.
|
|
.Pp
|
|
The
|
|
.Fn RMD160Data
|
|
function
|
|
calculates the digest of an arbitrary string and returns the result via
|
|
.Fn RMD160End .
|
|
.Pp
|
|
For each of the
|
|
.Fn RMD160End ,
|
|
.Fn RMD160File ,
|
|
and
|
|
.Fn RMD160Data
|
|
functions the
|
|
.Ar buf
|
|
parameter should either be a string of at least 41 characters in
|
|
size or a NULL pointer.
|
|
In the latter case, space will be dynamically allocated via
|
|
.Xr malloc 3
|
|
and should be freed using
|
|
.Xr free 3
|
|
when it is no longer needed.
|
|
.Sh EXAMPLES
|
|
The follow code fragment will calculate the digest for
|
|
the string "abc" which is ``0x8eb208f7e05d987a9b044a8e98c6b087f15a0bfc''.
|
|
.Bd -literal -offset indent
|
|
RMD160_CTX rmd;
|
|
u_char results[20];
|
|
char *buf;
|
|
int n;
|
|
|
|
buf = "abc";
|
|
n = strlen(buf);
|
|
RMD160Init(&rmd);
|
|
RMD160Update(&rmd, (u_char *)buf, n);
|
|
RMD160Final(results, &rmd);
|
|
|
|
/* Print the digest as one long hex value */
|
|
printf("0x");
|
|
for (n = 0; n < 20; n++)
|
|
printf("%02x", results[n]);
|
|
putchar('\\n');
|
|
.Ed
|
|
.Pp
|
|
Alternately, the helper functions could be used in the following way:
|
|
.Bd -literal -offset indent
|
|
RMD160_CTX rmd;
|
|
u_char output[41];
|
|
char *buf = "abc";
|
|
|
|
printf("0x%s\en", RMD160Data(buf, strlen(buf), output));
|
|
.Ed
|
|
.Sh CAVEATS
|
|
If a message digest is to be copied to a multi-byte type (ie:
|
|
an array of five 32-bit integers) it will be necessary to
|
|
perform byte swapping on little endian machines such as the i386, alpha,
|
|
and vax.
|
|
.Sh AUTHOR
|
|
This implementation of RMD-160 was written by Antoon Bosselaers.
|
|
.Pp
|
|
The
|
|
.Fn RMD160End ,
|
|
.Fn RMD160File ,
|
|
and
|
|
.Fn RMD160Data
|
|
helper functions are derived from code written by Poul-Henning Kamp.
|
|
.Sh SEE ALSO
|
|
.Xr rmd160 1 ,
|
|
.Xr md4 3 ,
|
|
.Xr md5 3 ,
|
|
.Xr sha1 3
|
|
.Pp
|
|
.Rs
|
|
.%A H. Dobbertin, A. Bosselaers, B. Preneel
|
|
.%T RIPEMD-160, a strengthened version of RIPEMD
|
|
.Re
|
|
.Rs
|
|
.%T Information technology - Security techniques - Hash-functions - Part 3: Dedicated hash-functions
|
|
.%O ISO/IEC 10118-3
|
|
.Re
|
|
.Rs
|
|
.%A H. Dobbertin, A. Bosselaers, B. Preneel
|
|
.%T The RIPEMD-160 cryptographic hash function
|
|
.%J Dr. Dobb's Journal
|
|
.%V Vol. 22, No. 1
|
|
.%D January 1997
|
|
.%P pp. 24-28
|
|
.Re
|
|
.Sh HISTORY
|
|
The RMD-160 functions appeared in
|
|
.Ox 2.1 .
|