.\" sha1.doc -  -*- Indented-Text -*- created at: Thu May 17 06:51:50 JST 2001

** SHA1(Class)

A class to implement the SHA1 Secure Hash Algorithm by NIST (the US'
National Institute of Standards and Technology), described in FIPS PUB
180-1.

Superclass: Object

Class Methods:

   new([str])
   sha1([str])

	Creates a new SHA1 object.  If a string argument is given, it
        is added to the object. (see update.)

Methods:

   clone

	Copies the SHA1 object.

   digest

	Returns the SHA1 hash of the added strings as a string of 20
	bytes.

   hexdigest

	Returns the SHA1 hash of the added strings as a string of 40
	hexadecimal digits.  This method is equal to:

	def hexdigest
	  ret = ''
	  digest.each_byte {|i| ret << sprintf('%02x', i) }
	  ret
	end

   update(str)
   << str

	Updates the SHA1 object with string str.  Repeated calls are
	equivalent to a single call with the concatenation of all the
	arguments, i.e. m.update(a); m.update(b) is equivalent to
	m.update(a+b) and m << a << b is equivalent to m << a+b.

Copyright:

	sha1.c is in the public domain.

-------------------------------------------------------
Local variables:
fill-column: 70
end: