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in reply to Re^6: convert hexadecimal value to encrypted string
in thread convert hexadecimal value to encrypted string

Let me get this straight...

You have a byte string, your plaintext, it being (as hex bytes) 38-32-33-35, or (as ASCII chars) '8235'.

You send it to your encryption server, and you get back a byte string, your cyphertext, it being (as base64) 'vY+TqCu5/Wdg6O+ilDqHVQ==', or (as hex bytes) bd-8f-93-a8-2b-b9-fd-67-60-e8-ef-a2-94-3a-87-55.

Then you have something in a field in a database, that should be the same cyphertext, stored as hex digits in a CHAR column. The value you have is (as hex digits) 63-9D-87-9F-22-4C-A2-A1-BA-73-CC-48-84-DB-D3-62.

It is not the same value as the one corresponding to the base64-encoded string you posted. Are you sure you are reading from the correct row in the table? Otherwise I missed some steps in your process.

-- 
        dakkar - Mobilis in mobile

Most of my code is tested...

Perl is strongly typed, it just has very few types (Dan)

  • Comment on Re^7: convert hexadecimal value to encrypted string

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Re^8: convert hexadecimal value to encrypted string
by linuxfan (Beadle) on Dec 11, 2004 at 22:49 UTC
    I am sure that the table and field names are correct. The encrypted string is stored as a RAW datatype in the table though. It is not CHAR.

    I am trying to verify that the cipher text stored on the database is the same as what I'd obtain by sending a seprate request (using telnet or nc) to the server.

    Two ways to do this would be

    • Extract the text on the database, send it in a decrypt request to the server and then compare the resulting plaintext with the original string(plain text)
    • Send the plaintext in an encrypt request to the server, extract the ciphertext from the response and compare it with the data stored on the database.

    In order to do the first bullet above, I want to obtain the "text" equivalent of the data stored in the database. A describe on the table shows that column from which I extract data is of type RAW (and not CHAR).

    As for the second bullet, I still need a way to convert the hex string on the database server to encrypted form so I can compare it with the encrypted string I receive from the server.

    Thank you

Re^8: convert hexadecimal value to encrypted string
by linuxfan (Beadle) on Dec 12, 2004 at 08:01 UTC
    Terribly sorry for posting an incorrect value of the Base64 encoded encrypted string. It is

    Y52HnyJMoqG6c8xIhNvTYg==

    Now will that help you in suggesting a conversion from the string in the database (639D879F224CA2A1BA73CC4884DBD362) to the a string that is the decoded value of the above base64 string?

    Many thanks

      This works for me:

      my $cypher1_b64='Y52HnyJMoqG6c8xIhNvTYg=='; my $cypher1=decode_base64($cypher1_b64); my $cypher2_hex='639D879F224CA2A1BA73CC4884DBD362'; my $cypher2=pack 'H*',$cypher2_hex; print "ok 1\n" if $cypher1 eq $cypher2;
      -- 
              dakkar - Mobilis in mobile
      

      Most of my code is tested...

      Perl is strongly typed, it just has very few types (Dan)

        Thanks Dakkar. Exactly what I was looking for. Using this solution I can verify the integrity of the encryption process.