4) Wait 1536 clocks while the module discards the first weak bytes of the stream as per RFC 4345.
4) Wait 1536 clocks while the module discards the first weak bytes of the stream as per RFC 4345.
5) Now you should start receiving the pseudo-random stream via the output bus, one byte every clock. The output_ready signal signals when a valid byte is present at the output K.
5) Now you should start receiving the pseudo-random stream via the output bus, one byte every clock. The output_ready signal signals when a valid byte is present at the output K.
To encrypt or decrypt using RC4 you simply xor your data with the output stream.
To encrypt or decrypt using RC4 you simply xor your data with the output stream.
WARNING: The 256-byte register that this implementation uses is very costly in FPGA resources and will result in >2000 slices used in some synthetizers.
The testbench and makefile work using icarus verilog and you can peer into rc4_tb.v to see an example implementation.
The testbench and makefile work using icarus verilog and you can peer into rc4_tb.v to see an example implementation.
After installing icarus verilog in your path, just issue:
After installing icarus verilog in your path, just issue: