This patch imports the unmodified current version of NetBSD libc. The NetBSD includes are in /nbsd_include, while the libc code itself is split between lib/nbsd_libc and common/lib/libc.
203 lines
5 KiB
Groff
203 lines
5 KiB
Groff
.\" $NetBSD: sha1.3,v 1.6 2010/04/05 21:27:01 joerg Exp $
|
|
.\" $OpenBSD: sha1.3,v 1.9 1998/03/07 22:18:12 millert Exp $
|
|
.\"
|
|
.\" Copyright (c) 1997, 2004 Todd C. Miller <Todd.Miller@courtesan.com>
|
|
.\"
|
|
.\" Permission to use, copy, modify, and distribute this software for any
|
|
.\" purpose with or without fee is hereby granted, provided that the above
|
|
.\" copyright notice and this permission notice appear in all copies.
|
|
.\"
|
|
.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
|
|
.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
|
|
.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
|
|
.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
|
|
.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
|
|
.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
|
|
.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
|
|
.\"
|
|
.\" See http://csrc.nist.gov/fips/fip180-1.txt for the detailed standard
|
|
.\"
|
|
.Dd July 10, 1997
|
|
.Dt SHA1 3
|
|
.Os
|
|
.Sh NAME
|
|
.Nm SHA1Init ,
|
|
.Nm SHA1Update ,
|
|
.Nm SHA1Final ,
|
|
.Nm SHA1Transform ,
|
|
.Nm SHA1End ,
|
|
.Nm SHA1File ,
|
|
.Nm SHA1Data
|
|
.Nd calculate the NIST Secure Hash Algorithm
|
|
.Sh SYNOPSIS
|
|
.In sys/types.h
|
|
.In sha1.h
|
|
.Ft void
|
|
.Fn SHA1Init "SHA1_CTX *context"
|
|
.Ft void
|
|
.Fn SHA1Update "SHA1_CTX *context" "const uint8_t *data" "u_int len"
|
|
.Ft void
|
|
.Fn SHA1Final "uint8_t digest[20]" "SHA1_CTX *context"
|
|
.Ft void
|
|
.Fn SHA1Transform "uint32_t state[5]" "uint8_t buffer[64]"
|
|
.Ft "char *"
|
|
.Fn SHA1End "SHA1_CTX *context" "char *buf"
|
|
.Ft "char *"
|
|
.Fn SHA1File "char *filename" "char *buf"
|
|
.Ft "char *"
|
|
.Fn SHA1Data "uint8_t *data" "size_t len" "char *buf"
|
|
.Sh DESCRIPTION
|
|
The SHA1 functions implement the 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 SHA1_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.
|
|
When a null pointer is passed to
|
|
.Fn SHA1Final
|
|
as first argument only the final padding will be applied and the
|
|
current context can still be used with
|
|
.Fn SHA1Update .
|
|
.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.
|
|
.Pp
|
|
The
|
|
.Fn SHA1End
|
|
function is a front end for
|
|
.Fn SHA1Final
|
|
which converts the digest into an
|
|
.Tn ASCII
|
|
representation of the 160 bit digest in hexadecimal.
|
|
.Pp
|
|
The
|
|
.Fn SHA1File
|
|
function calculates the digest for a file and returns the result via
|
|
.Fn SHA1End .
|
|
If
|
|
.Fn SHA1File
|
|
is unable to open the file a NULL pointer is returned.
|
|
.Pp
|
|
The
|
|
.Fn SHA1Data
|
|
function
|
|
calculates the digest of an arbitrary string and returns the result via
|
|
.Fn SHA1End .
|
|
.Pp
|
|
For each of the
|
|
.Fn SHA1End ,
|
|
.Fn SHA1File ,
|
|
and
|
|
.Fn SHA1Data
|
|
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 ``0xa9993e36476816aba3e25717850c26c9cd0d89d''.
|
|
.Bd -literal -offset indent
|
|
SHA1_CTX sha;
|
|
uint8_t results[20];
|
|
char *buf;
|
|
int n;
|
|
|
|
buf = "abc";
|
|
n = strlen(buf);
|
|
SHA1Init(\*[Am]sha);
|
|
SHA1Update(\*[Am]sha, (uint8_t *)buf, n);
|
|
SHA1Final(results, \*[Am]sha);
|
|
|
|
/* Print the digest as one long hex value */
|
|
printf("0x");
|
|
for (n = 0; n \*[Lt] 20; n++)
|
|
printf("%02x", results[n]);
|
|
putchar('\en');
|
|
.Ed
|
|
.Pp
|
|
Alternately, the helper functions could be used in the following way:
|
|
.Bd -literal -offset indent
|
|
SHA1_CTX sha;
|
|
uint8_t output[41];
|
|
char *buf = "abc";
|
|
|
|
printf("0x%s", SHA1Data(buf, strlen(buf), output));
|
|
.Ed
|
|
.Sh SEE ALSO
|
|
.\" .Xr sha1 1 ,
|
|
.Xr md5 1 ,
|
|
.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
|
|
.Nx 1.4 .
|
|
.Sh AUTHORS
|
|
This implementation of SHA-1 was written by Steve Reid.
|
|
.Pp
|
|
The
|
|
.Fn SHA1End ,
|
|
.Fn SHA1File ,
|
|
and
|
|
.Fn SHA1Data
|
|
helper functions are derived from code written by Poul-Henning Kamp.
|
|
.Sh BUGS
|
|
This implementation of SHA-1 has not been validated 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 necessary to
|
|
perform byte swapping on little endian machines such as the i386, alpha,
|
|
and VAX.
|