diff --git a/python-ecosys/aes-cmac/aes_cmac.py b/python-ecosys/aes-cmac/aes_cmac.py
new file mode 100644
index 000000000..9cac1d105
--- /dev/null
+++ b/python-ecosys/aes-cmac/aes_cmac.py
@@ -0,0 +1,74 @@
+#!/usr/bin/python3
+
+import cryptolib
+from binascii import hexlify
+from math import ceil
+
+
+class CMAC:
+ def _xor(self, a, b):
+ return bytes(x ^ y for x, y in zip(a, b))
+
+ def _e(self, key, plain):
+ aes = cryptolib.aes(key, 1) # Using ECB mode
+ return aes.encrypt(plain)
+
+ def _d(self, key, enc):
+ aes = cryptolib.aes(key, 1) # Using ECB mode
+ return aes.decrypt(enc)
+
+ def generate_subkey(self, k):
+ const_zero = b"\x00" * 16
+ const_rb = b"\x87" + b"\x00" * 15 # Adjusted to align with common CMAC practices
+
+ # Step 1
+ l = self._e(k, const_zero)
+
+ # Step 2 and 3
+ def shift_left(bit_string):
+ shifted = int.from_bytes(bit_string, "big") << 1
+ if bit_string[0] & 0x80:
+ shifted ^= 0x100000000000000000000000000000087 # Apply Rb polynomial
+ return shifted.to_bytes(16, "big")
+
+ k1 = shift_left(l)
+ k2 = shift_left(k1)
+
+ return k1, k2
+
+ def aes_cmac(self, k, m):
+ const_zero = b"\x00" * 16
+ const_bsize = 16
+
+ # Step 1
+ k1, k2 = self.generate_subkey(k)
+
+ # Step 2
+ n = ceil(len(m) / const_bsize)
+ m_block = [m[i * const_bsize : (i + 1) * const_bsize] for i in range(n)]
+
+ # Step 3
+ if n == 0:
+ n = 1
+ m_block = [b""]
+ flag = False
+ else:
+ flag = len(m) % const_bsize == 0
+
+ # Step 4
+ if flag:
+ m_last = self._xor(m_block[-1], k1)
+ else:
+ padding = b"\x80" + b"\x00" * (const_bsize - len(m_block[-1]) - 1)
+ m_last = self._xor(m_block[-1] + padding, k2)
+
+ # Step 5 and 6
+ x = const_zero
+ for block in m_block[:-1]:
+ y = self._xor(x, block)
+ x = self._e(k, y)
+ y = self._xor(m_last, x)
+ t = self._e(k, y)
+
+ # Step 7
+ return t
diff --git a/python-ecosys/aes-cmac/manifest.py b/python-ecosys/aes-cmac/manifest.py
new file mode 100644
index 000000000..3c99486f9
--- /dev/null
+++ b/python-ecosys/aes-cmac/manifest.py
@@ -0,0 +1,2 @@
+metadata(description="CMAC using AES from built in cryptolib library", version="0.1.0")
+module("aes_cmac.py")
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