(Began SHA-1 walkthrough)
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Hey Today we are talking about code anoymization. Let's Define an equation: <math>Y=x^2
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Hey Today we are talking about code anoymization. Let's Define an equation: <math>Y=x^2</math>
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== SHA-1 Walkthrough ==
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===== Step 1: =====
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Initialize 5 Random strings
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H1 = 0x67452301 <br/>
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H2 = 0xEFCDAB89 <br/>
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H3 = 0x98BADCFE <br/>
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H4 = 0x10325476 <br/>
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H5 = 0xC3D2E1F0 <br/>
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===== Step 2: =====
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Take the word you want to hash (in binary), and append a 1 to the end of it. Then append as many zeros as it takes to make it divisible by 512, with the length of the message in a 64 bit integer appended at the end of the string.
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Example:
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The word "Hello" in binary is:
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                      01001000 01100101 01101100 01101100 01101111
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                        (H)      (e)      (l)      (l)      (o)
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Add 1 to the end:
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= 0100100001100101011011000110110001101111<span style="color:red">1</span>
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Since hello is less than 448 we add 0’s until the string is 448 bits long:
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= 01001000011001010110110001101100011011111<span style="color:red">000…0</span> (len = 448 bits)
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Lastly take the length of the string before processing (40 bits in this case) append that as a 64 bit integer
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= <span style="color:red">...0000101000</span> (length of added bits = 64)
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So total length is '''512''' in this example
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010010000110010101101100011011000110111110………0101000
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====Step 3====

Revision as of 23:21, 28 November 2022

Hey Today we are talking about code anoymization. Let's Define an equation: $ Y=x^2 $


SHA-1 Walkthrough

Step 1:

Initialize 5 Random strings

H1 = 0x67452301
H2 = 0xEFCDAB89
H3 = 0x98BADCFE
H4 = 0x10325476
H5 = 0xC3D2E1F0

Step 2:

Take the word you want to hash (in binary), and append a 1 to the end of it. Then append as many zeros as it takes to make it divisible by 512, with the length of the message in a 64 bit integer appended at the end of the string.

Example:

The word "Hello" in binary is:

                     01001000 01100101 01101100 01101100 01101111
                       (H)      (e)      (l)      (l)      (o)

Add 1 to the end:

= 01001000011001010110110001101100011011111

Since hello is less than 448 we add 0’s until the string is 448 bits long:

= 01001000011001010110110001101100011011111000…0 (len = 448 bits)

Lastly take the length of the string before processing (40 bits in this case) append that as a 64 bit integer

= ...0000101000 (length of added bits = 64)

So total length is 512 in this example

010010000110010101101100011011000110111110………0101000

Step 3

Alumni Liaison

Ph.D. on Applied Mathematics in Aug 2007. Involved on applications of image super-resolution to electron microscopy

Francisco Blanco-Silva