# subbytes.py

import pyrtl
from pyrtl import *

# S-box table.
sbox_data = [0x63, 0x7c, 0x77, 0x7b, 0xf2, 0x6b, 0x6f, 0xc5, 0x30, 0x01, 0x67, 0x2b, 0xfe, 0xd7, 0xab, 0x76, 0xca, 0x82, 0xc9, 0x7d, 0xfa, 0x59, 0x47, 0xf0, 0xad, 0xd4, 0xa2, 0xaf, 0x9c, 0xa4, 0x72, 0xc0, 0xb7, 0xfd, 0x93, 0x26, 0x36, 0x3f, 0xf7, 0xcc, 0x34, 0xa5, 0xe5, 0xf1, 0x71, 0xd8, 0x31, 0x15, 0x04, 0xc7, 0x23, 0xc3, 0x18, 0x96, 0x05, 0x9a, 0x07, 0x12, 0x80, 0xe2, 0xeb, 0x27, 0xb2, 0x75, 0x09, 0x83, 0x2c, 0x1a, 0x1b, 0x6e, 0x5a, 0xa0, 0x52, 0x3b, 0xd6, 0xb3, 0x29, 0xe3, 0x2f, 0x84, 0x53, 0xd1, 0x00, 0xed, 0x20, 0xfc, 0xb1, 0x5b, 0x6a, 0xcb, 0xbe, 0x39, 0x4a, 0x4c, 0x58, 0xcf, 0xd0, 0xef, 0xaa, 0xfb, 0x43, 0x4d, 0x33, 0x85, 0x45, 0xf9, 0x02, 0x7f, 0x50, 0x3c, 0x9f, 0xa8, 0x51, 0xa3, 0x40, 0x8f, 0x92, 0x9d, 0x38, 0xf5, 0xbc, 0xb6, 0xda, 0x21, 0x10, 0xff, 0xf3, 0xd2, 0xcd, 0x0c, 0x13, 0xec, 0x5f, 0x97, 0x44, 0x17, 0xc4, 0xa7, 0x7e, 0x3d, 0x64, 0x5d, 0x19, 0x73, 0x60, 0x81, 0x4f, 0xdc, 0x22, 0x2a, 0x90, 0x88, 0x46, 0xee, 0xb8, 0x14, 0xde, 0x5e, 0x0b, 0xdb, 0xe0, 0x32, 0x3a, 0x0a, 0x49, 0x06, 0x24, 0x5c, 0xc2, 0xd3, 0xac, 0x62, 0x91, 0x95, 0xe4, 0x79, 0xe7, 0xc8, 0x37, 0x6d, 0x8d, 0xd5, 0x4e, 0xa9, 0x6c, 0x56, 0xf4, 0xea, 0x65, 0x7a, 0xae, 0x08, 0xba, 0x78, 0x25, 0x2e, 0x1c, 0xa6, 0xb4, 0xc6, 0xe8, 0xdd, 0x74, 0x1f, 0x4b, 0xbd, 0x8b, 0x8a, 0x70, 0x3e, 0xb5, 0x66, 0x48, 0x03, 0xf6, 0x0e, 0x61, 0x35, 0x57, 0xb9, 0x86, 0xc1, 0x1d, 0x9e, 0xe1, 0xf8, 0x98, 0x11, 0x69, 0xd9, 0x8e, 0x94, 0x9b, 0x1e, 0x87, 0xe9, 0xce, 0x55, 0x28, 0xdf, 0x8c, 0xa1, 0x89, 0x0d, 0xbf, 0xe6, 0x42, 0x68, 0x41, 0x99, 0x2d, 0x0f, 0xb0, 0x54, 0xbb, 0x16]
sbox = RomBlock(bitwidth=128, addrwidth=8, data=sbox_data)

def SubBytes(in_vector):
	""" SubBytes round of AES.

	Input: A single wirevector of bitwidth 128.
	Output: A single wirevector of bitwidth 128.
	"""

	a00 = in_vector[120:128]
	a01 = in_vector[112:120]
	a02 = in_vector[104:112]
	a03 = in_vector[96:104]
	a10 = in_vector[88:96]
	a11 = in_vector[80:88]
	a12 = in_vector[72:80]
	a13 = in_vector[64:72]
	a20 = in_vector[56:64]
	a21 = in_vector[48:56]
	a22 = in_vector[40:48]
	a23 = in_vector[32:40]
	a30 = in_vector[24:32]
	a31 = in_vector[16:24]
	a32 = in_vector[8:16]
	a33 = in_vector[0:8]

	b00 = sbox[a00]
	b01 = sbox[a01]
	b02 = sbox[a02]
	b03 = sbox[a03]
	b10 = sbox[a10]
	b11 = sbox[a11]
	b12 = sbox[a12]
	b13 = sbox[a13]
	b20 = sbox[a20]
	b21 = sbox[a21]
	b22 = sbox[a22]
	b23 = sbox[a23]
	b30 = sbox[a30]
	b31 = sbox[a31]
	b32 = sbox[a32]
	b33 = sbox[a33]

	out_vector = pyrtl.concat(b00, b01, b02, b03,
					b10, b11, b12, b13,
					b20, b21, b22, b23,
					b30, b31, b32, b33)

	return out_vector

# Hardware build.
aes_input = pyrtl.Input(bitwidth=128, name='aes_input')
aes_output = pyrtl.Output(bitwidth=128, name='aes_output')
aes_output <<= SubBytes(aes_input)

print pyrtl.working_block()
print 

sim_trace = pyrtl.SimulationTrace()
sim = pyrtl.Simulation(tracer=sim_trace)

for cycle in range(1):
	sim.step({aes_input: 0x53})

sim_trace.render_trace(symbol_len=12, segment_size=5)

Create subbytes.py