Caesar cipher coded in Assembly
This is an implementation of a variant of Speck with 128-bit block size and key using ARM Assembly. C code for this programe can be found in Wikipedea. Here this is the Assembly implementation of the programe.
Program should behave like the following:
Enter the key: 0f0e0d0c0b0a0908 0706050403020100 Enter the plain text: 6c61766975716520 7469206564616d20 Cipher text is: a65d985179783265 7860fedf5c570d18
All the inputs and outputs are in hexadecimal. 128-bit version of Speck uses 64-bit unsigned integers for calculation and hence observe that each input and output above has 2 separate numbers in hexadecimal.
Facts: ARM has 32 bit registers but here the operations are done on 64 bit unsigned integers which is a quite challenging tast.