Add simple example verifying an aes unit

.gitignore

@@ -0,0 +1,3 @@
+cryptocores
+libvhdl
+cocotbext-wishbone

env-setup.sh

@@ -7,5 +7,9 @@ if [ ! -d cocotbext-wishbone/.git ]; then
 fi
 
 if [ ! -d libvhdl/.git ]; then
-  git clone https://github.com/tmeissner/libvhdl.git	
+  git clone https://github.com/tmeissner/libvhdl.git
+fi
+
+if [ ! -d cryptocores/.git ]; then
+  git clone https://github.com/tmeissner/cryptocores.git
 fi

requirements.txt

@@ -15,3 +15,4 @@ pyuvm
 
 # utilities
 wavedrom
+pycryptodome

tests/Vai.py

@@ -8,7 +8,7 @@ class Vai:
     def __init__(self, clock, data, valid, accept, *args, **kwargs):
         self._version = "0.0.1"
 
-        self.log = logging.getLogger(f"cocotb.{data._path}")
+        self.log = logging.getLogger(f"cocotb.{valid._path}")
 
         self._data = data
         self._valid = valid
@@ -28,17 +28,26 @@ class VaiDriver(Vai):
         self.log.info("  cocotbext-vai version %s", self._version)
         self.log.info("  Copyright (c) 2022 Torsten Meissner")
 
-        # Drive input defaults (setimmediatevalue to avoid x asserts)
-        self._data.setimmediatevalue(0)
+        # Hack to drive lists of signals
+        if isinstance(self._data, list):
+            for entry in self._data:
+                entry.setimmediatevalue(0)
+        else:
+            self._data.setimmediatevalue(0)
         self._valid.setimmediatevalue(0)
 
     async def send(self, data, sync=True):
         if sync:
             await self._clkedge
 
-        self.log.info("Sending data:  %s", hex(data))
         self._valid.value = 1
-        self._data.value = data
+        # Hack to drive lists of signals
+        if isinstance(self._data, list):
+            for i in range(len(self._data)):
+                self._data[i].value = data[i]
+        else:
+            self.log.info("Sending data:  %s", hex(data))
+            self._data.value = data
 
         while True:
             await ReadOnly()

tests/tb_aes.py

@@ -0,0 +1,105 @@
+import logging
+import random
+import cocotb
+import pprint
+from Vai import VaiDriver, VaiReceiver
+from cocotb.clock import Clock
+from cocotb.triggers import FallingEdge, RisingEdge, Timer, ReadOnly
+from Crypto.Cipher import AES
+from Crypto.Util.number import long_to_bytes, getRandomNBitInteger
+import binascii
+
+
+# Reset coroutine
+async def reset_dut(reset_n, duration_ns):
+    reset_n.value = 0
+    await Timer(duration_ns, units="ns")
+    reset_n.value = 1
+
+
+@cocotb.test()
+async def test_aes_enc(dut):
+    """ Test AES encryption """
+
+    clkedge = RisingEdge(dut.clk_i)
+
+    # Connect reset
+    reset = dut.reset_i
+
+    # Instantiate VAI driver & receiver
+    _input = [dut.mode_i, dut.key_i, dut.data_i]
+    vai_driver = VaiDriver(dut.clk_i, _input, dut.valid_i, dut.accept_o)
+    vai_receiver = VaiReceiver(dut.clk_i, dut.data_o, dut.valid_o, dut.accept_i)
+
+    # Drive input defaults (setimmediatevalue to avoid x asserts)
+    dut.mode_i.setimmediatevalue(0)
+    dut.key_i.setimmediatevalue(0)
+    dut.data_i.setimmediatevalue(0)
+    dut.valid_i.setimmediatevalue(0)
+    dut.accept_i.setimmediatevalue(0)
+
+    clock = Clock(dut.clk_i, 10, units="ns")  # Create a 10 ns period clock
+    cocotb.start_soon(clock.start())  # Start the clock
+
+    # Execution will block until reset_dut has completed
+    dut._log.info("Hold reset")
+    await reset_dut(reset, 100)
+    dut._log.info("Released reset")
+
+    # Test 10 AES calculations
+    for i in range(10):
+        await clkedge
+        _key = getRandomNBitInteger(128)
+        _data = getRandomNBitInteger(128)
+        # Drive AES inputs
+        await vai_driver.send([0, _key, _data])
+        # Calc reference data
+        _aes = AES.new(long_to_bytes(_key), AES.MODE_ECB)
+        _ref = _aes.encrypt(long_to_bytes(_data))
+        # Get DUT output data
+        _rec = await vai_receiver.receive()
+        assert _rec.buff == _ref, f"Encrypt error, got {_rec.buff}, expected {_ref}"
+
+
+@cocotb.test()
+async def test_aes_dec(dut):
+    """ Test AES decryption """
+
+    clkedge = RisingEdge(dut.clk_i)
+
+    # Connect reset
+    reset = dut.reset_i
+
+    # Instantiate VAI driver & receiver
+    _input = [dut.mode_i, dut.key_i, dut.data_i]
+    vai_driver = VaiDriver(dut.clk_i, _input, dut.valid_i, dut.accept_o)
+    vai_receiver = VaiReceiver(dut.clk_i, dut.data_o, dut.valid_o, dut.accept_i)
+
+    # Drive input defaults (setimmediatevalue to avoid x asserts)
+    dut.mode_i.setimmediatevalue(0)
+    dut.key_i.setimmediatevalue(0)
+    dut.data_i.setimmediatevalue(0)
+    dut.valid_i.setimmediatevalue(0)
+    dut.accept_i.setimmediatevalue(0)
+
+    clock = Clock(dut.clk_i, 10, units="ns")  # Create a 10 ns period clock
+    cocotb.start_soon(clock.start())  # Start the clock
+
+    # Execution will block until reset_dut has completed
+    dut._log.info("Hold reset")
+    await reset_dut(reset, 100)
+    dut._log.info("Released reset")
+
+    # Test 10 AES calculations
+    for i in range(10):
+        await clkedge
+        _key = getRandomNBitInteger(128)
+        _data = getRandomNBitInteger(128)
+        # Drive AES inputs
+        await vai_driver.send([1, _key, _data])
+        # Calc reference data
+        _aes = AES.new(long_to_bytes(_key), AES.MODE_ECB)
+        _ref = _aes.decrypt(long_to_bytes(_data))
+        # Get DUT output data
+        _rec = await vai_receiver.receive()
+        assert _rec.buff == _ref, f"Decrypt error, got {_rec.buff}, expected {_ref}"