Article:		Atom Authentication
Subject:		Base64 encoding of SHA1 digest
Date:		2003-12-18 07:01:13
From:		Piotr Lakomy
The base64 encoding of the SHA1(Password + CreationTimestamp + Nonce) should be "quR/EWLAV4xLf9Zqyw4pDmfV9OY". Looks like example in the article applies base64 to to the hex encoding of SHA1 value: base64("aae47f1162c0578c4b7fd66acb0e290e67d5f4e6") = "YWFlNDdmMTE2MmMwNTc4YzRiN2ZkNjZhY2IwZTI5MGU2N2Q1ZjRlNg==" (Note two filler "=" charactes at the end). Here is perl code to verify: use Digest::SHA1 qw(sha1 sha1_hex sha1_base64);; use MIME::Base64 qw(encode_base64); $password = "taadtaadpstcsm"; $nonce = "d36e316282959a9ed4c89851497a717f"; $timestamp = "2003-12-15T14:43:07Z"; $text = $nonce . $timestamp . $password; print "text = $text\n"; print "SHA1 hex = " . sha1_hex($text) . "\n"; print "SHA1 b64 = " . sha1_base64($text) . "\n"; print "SHA1 b64(hex) = " . encode_base64(sha1_hex($text)); Very good article, I like it.

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• Base64 encoding of SHA1 digest
  2006-01-11 07:57:52 JY123 [Reply]
  
  Hi,
  I am working on a project that needs "Base64 encoding of SHA1 digest". Your article is very helpful. I have downloaded sha1 code from http://www.veign.com/vrc_codeview.asp?type=app&id=76, and wrote a Base64 code. Both are tested successfully using known examples.

  
  But I failed to reproduce your results when I calculate Base64(sha1(Nonce+TimeStamp+Password).
  The input string I used is:

  
  d36e316282959a9ed4c89851497a717f2003-12-15T14:43:07Ztaadtaadpstcsm

  
  But the result I got is:
  sha1=BADE76A5F7B0AFDE6D96BDEE566AAAACECEA7B75
  base64=QkFERTc2QTVGN0IwQUZERTZEOTZCREVFNTY2QUFBQUNFQ0VBN0I3NQ==

  
  I could not reproduce your result. What did I miss? Please let me know.

  
  Thanks
  Jack Yan
  
  

• Base64 encoding of SHA1 digest
  2003-12-21 22:38:58 Mark Pilgrim [Reply]
  
  Thanks, you are absolutely correct. We have updated the article to reflect this change.