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heig:su16:sre:lab2 [2016/07/11 12:21] – Laureline Davidheig:su16:sre:lab2 [2018/01/30 16:39] (current) – external edit 127.0.0.1
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 ====== Lab 2 - Hash Collisions Galore ====== ====== Lab 2 - Hash Collisions Galore ======
  
-Upon its first execution the ''L2'' binary asks the user to generate 1024 passwords. With this information we can assume than the password is not directly hardcoded in the binary but will be processed and compared against a reference value and that this process will process at least 1024 passwords to this value. +Upon its first execution the ''L2'' binary asks the user to generate 1024 passwords. With this information we can assume that the password is not directly hardcoded in the binary but will be processed and compared against a reference value and that this process will map at least 1024 passwords to this value.
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-/* {{ :heig:su16:sre:lab2-output.png?nolink&200 |Lab 2 output}} */+
  
 Using this assumption we can assume that the binary computes a hash of the given password and check it against a reference hash. Moreover due to the need to provide multiple passwords, we can assume that this hash function is weak against collitions. Using this assumption we can assume that the binary computes a hash of the given password and check it against a reference hash. Moreover due to the need to provide multiple passwords, we can assume that this hash function is weak against collitions.
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       print("Password:", pwd)       print("Password:", pwd)
  
-Note that the last two values are swapped from their order in the desired hash. The total number of passwords can be obtained by multiplying the size of the four sets and is **1781102812020000** (or 18.98Pb of data).+Note that the last two values are swapped from their order in the desired hash. The total number of passwords can be obtained by multiplying the size of the four sets and is **1781102812020000** (or 18.98Pb of data or 1.58Pb by compressing data).