Digest::SHA1 man page on YellowDog

Man page or keyword search:  
man Server   18644 pages
apropos Keyword Search (all sections)
Output format
YellowDog logo
[printable version]

SHA1(3)		      User Contributed Perl Documentation	       SHA1(3)

NAME
       Digest::SHA1 - Perl interface to the SHA-1 algorithm

SYNOPSIS
	# Functional style
	use Digest::SHA1  qw(sha1 sha1_hex sha1_base64);

	$digest = sha1($data);
	$digest = sha1_hex($data);
	$digest = sha1_base64($data);
	$digest = sha1_transform($data);

	# OO style
	use Digest::SHA1;

	$sha1 = Digest::SHA1->new;

	$sha1->add($data);
	$sha1->addfile(*FILE);

	$sha1_copy = $sha1->clone;

	$digest = $sha1->digest;
	$digest = $sha1->hexdigest;
	$digest = $sha1->b64digest;
	$digest = $sha1->transform;

DESCRIPTION
       The "Digest::SHA1" module allows you to use the NIST SHA-1 message
       digest algorithm from within Perl programs.  The algorithm takes as
       input a message of arbitrary length and produces as output a 160-bit
       "fingerprint" or "message digest" of the input.

       The "Digest::SHA1" module provide a procedural interface for simple
       use, as well as an object oriented interface that can handle messages
       of arbitrary length and which can read files directly.

FUNCTIONS
       The following functions can be exported from the "Digest::SHA1" module.
       No functions are exported by default.

       sha1($data,...)
	   This function will concatenate all arguments, calculate the SHA-1
	   digest of this "message", and return it in binary form.  The
	   returned string will be 20 bytes long.

	   The result of sha1("a", "b", "c") will be exactly the same as the
	   result of sha1("abc").

       sha1_hex($data,...)
	   Same as sha1(), but will return the digest in hexadecimal form.
	   The length of the returned string will be 40 and it will only con‐
	   tain characters from this set: '0'..'9' and 'a'..'f'.

       sha1_base64($data,...)
	   Same as sha1(), but will return the digest as a base64 encoded
	   string.  The length of the returned string will be 27 and it will
	   only contain characters from this set: 'A'..'Z', 'a'..'z',
	   '0'..'9', '+' and '/'.

	   Note that the base64 encoded string returned is not padded to be a
	   multiple of 4 bytes long.  If you want interoperability with other
	   base64 encoded sha1 digests you might want to append the redundant
	   string "=" to the result.

       sha1_transform($data)
	   Implements the basic SHA1 transform on a 64 byte block. The $data
	   argument and the returned $digest are in binary form. This algo‐
	   rithm is used in NIST FIPS 186-2

METHODS
       The object oriented interface to "Digest::SHA1" is described in this
       section.	 After a "Digest::SHA1" object has been created, you will add
       data to it and finally ask for the digest in a suitable format.	A sin‐
       gle object can be used to calculate multiple digests.

       The following methods are provided:

       $sha1 = Digest::SHA1->new
	   The constructor returns a new "Digest::SHA1" object which encapsu‐
	   late the state of the SHA-1 message-digest algorithm.

	   If called as an instance method (i.e. $sha1->new) it will just
	   reset the state the object to the state of a newly created object.
	   No new object is created in this case.

       $sha1->reset
	   This is just an alias for $sha1->new.

       $sha1->clone
	   This a copy of the $sha1 object. It is useful when you do not want
	   to destroy the digests state, but need an intermediate value of the
	   digest, e.g. when calculating digests iteratively on a continuous
	   data stream.	 Example:

	       my $sha1 = Digest::SHA1->new;
	       while (<>) {
		   $sha1->add($_);
		   print "Line $.: ", $sha1->clone->hexdigest, "\n";
	       }

       $sha1->add($data,...)
	   The $data provided as argument are appended to the message we cal‐
	   culate the digest for.  The return value is the $sha1 object
	   itself.

	   All these lines will have the same effect on the state of the $sha1
	   object:

	       $sha1->add("a"); $sha1->add("b"); $sha1->add("c");
	       $sha1->add("a")->add("b")->add("c");
	       $sha1->add("a", "b", "c");
	       $sha1->add("abc");

       $sha1->addfile($io_handle)
	   The $io_handle will be read until EOF and its content appended to
	   the message we calculate the digest for.  The return value is the
	   $sha1 object itself.

	   The addfile() method will croak() if it fails reading data for some
	   reason.  If it croaks it is unpredictable what the state of the
	   $sha1 object will be in. The addfile() method might have been able
	   to read the file partially before it failed.	 It is probably wise
	   to discard or reset the $sha1 object if this occurs.

	   In most cases you want to make sure that the $io_handle is in "bin‐
	   mode" before you pass it as argument to the addfile() method.

       $sha1->add_bits($data, $nbits)
       $sha1->add_bits($bitstring)
	   This implementation of SHA-1 only supports byte oriented input so
	   you might only add bits as multiples of 8.  If you need bit level
	   support please consider using the "Digest::SHA" module instead.
	   The add_bits() method is provided here for compatibility with other
	   digest implementations.  See Digest for description of the argu‐
	   ments that add_bits() take.

       $sha1->digest
	   Return the binary digest for the message.  The returned string will
	   be 20 bytes long.

	   Note that the "digest" operation is effectively a destructive,
	   read-once operation. Once it has been performed, the "Digest::SHA1"
	   object is automatically "reset" and can be used to calculate
	   another digest value.  Call $sha1->clone->digest if you want to
	   calculate the digest without reseting the digest state.

       $sha1->hexdigest
	   Same as $sha1->digest, but will return the digest in hexadecimal
	   form. The length of the returned string will be 40 and it will only
	   contain characters from this set: '0'..'9' and 'a'..'f'.

       $sha1->b64digest
	   Same as $sha1->digest, but will return the digest as a base64
	   encoded string.  The length of the returned string will be 27 and
	   it will only contain characters from this set: 'A'..'Z', 'a'..'z',
	   '0'..'9', '+' and '/'.

	   The base64 encoded string returned is not padded to be a multiple
	   of 4 bytes long.  If you want interoperability with other base64
	   encoded SHA-1 digests you might want to append the string "=" to
	   the result.

SEE ALSO
       Digest, Digest::HMAC_SHA1, Digest::SHA, Digest::MD5

       http://www.itl.nist.gov/fipspubs/fip180-1.htm

COPYRIGHT
       This library is free software; you can redistribute it and/or modify it
       under the same terms as Perl itself.

	Copyright 1999-2004 Gisle Aas.
	Copyright 1997 Uwe Hollerbach.

AUTHORS
       Peter C. Gutmann, Uwe Hollerbach <uh@alumni.caltech.edu>, Gisle Aas
       <gisle@aas.no>

perl v5.8.8			  2006-01-18			       SHA1(3)
[top]

List of man pages available for YellowDog

Copyright (c) for man pages and the logo by the respective OS vendor.

For those who want to learn more, the polarhome community provides shell access and support.

[legal] [privacy] [GNU] [policy] [cookies] [netiquette] [sponsors] [FAQ]
Tweet
Polarhome, production since 1999.
Member of Polarhome portal.
Based on Fawad Halim's script.
....................................................................
Vote for polarhome
Free Shell Accounts :: the biggest list on the net