Traduction de genkat_aead.c en Python

Et   ré-adaptation   de   l'API   de   lilliput.py   pour   simplifier
l'interfaçage ;  et retrait des  print() pour accélérer  la génération
des vecteurs (qui même comme ça prend 2 bonnes minutes).

NB : pour le moment, les vecteurs ne correspondent pas…

3 files changed, 76 insertions, 17 deletions

diff --git a/python/genkat_aead.py b/python/genkat_aead.py
new file mode 100755
index 0000000..5a50e03
--- /dev/null
+++ b/python/genkat_aead.py
@@ -0,0 +1,72 @@
+#!/usr/bin/env python3
+
+import lilliput
+
+
+MAX_MESSAGE_LENGTH = 32
+MAX_ADATA_LENGTH = 32
+
+CRYPTO_NPUBBYTES = 120//8
+
+
+def bstr(buf):
+    return ''.join('{:02X}'.format(b) for b in buf)
+
+
+def print_bstr(output, label, buf):
+    print('{l} = {b}'.format(l=label, b=bstr(buf)), file=output)
+
+
+class DecryptionError(Exception):
+    def __init__(self, expected, actual, mode, keylen):
+        self.expected = expected
+        self.actual = actual
+        self.mode = mode
+        self.keylen = keylen
+        
+    def __str__(self):
+        return '({s.mode} / {s.keylen}) Expected {exp}; got {act}'.format(
+            s=self,
+            exp=bstr(self.expected),
+            act=bstr(self.actual)
+        )
+
+
+def generate_test_vectors(mode, keylen):
+
+    print('generating for', mode, keylen)
+
+    output_path = 'LWC_AEAD_KAT_{mode}_{keylen}'.format(mode=mode, keylen=keylen)
+    with open(output_path, 'w') as output:
+
+        count = 1
+        for mlen in range(MAX_MESSAGE_LENGTH+1):
+            for adlen in range(MAX_ADATA_LENGTH+1):
+                print('Count = {c}'.format(c=count), file=output)
+
+                msg = bytes(range(mlen))
+                ad = bytes(range(adlen))
+
+                print_bstr(output, 'Key', bytes(range(keylen//8)))
+                print_bstr(output, 'Nonce', bytes(range(CRYPTO_NPUBBYTES)))
+                print_bstr(output, 'PT', msg)
+                print_bstr(output, 'AD', ad)
+
+                ct, tag = lilliput.mainEnc(msg, ad, mode, keylen)
+
+                print_bstr(output, 'CT', ct+tag)
+
+                msg2 = lilliput.mainDec(ct, tag, ad, mode, keylen)
+
+                if msg != msg2:
+                    raise DecryptionError(msg, msg2, mode, keylen)
+
+                count+=1
+
+                print(file=output)
+
+
+if __name__ == '__main__':
+    for mode in 1, 2:
+        for keylen in 128, 192, 256:
+            generate_test_vectors(mode, keylen)
diff --git a/python/lilliput.py b/python/lilliput.py
index 6a2aae4..c2e1a69 100644
--- a/python/lilliput.py
+++ b/python/lilliput.py
@@ -57,8 +57,8 @@ def mainEnc(plaintext, adata, mode=1, length=128):
 
     (key_bits, tweak_bits, rounds) = GetParameters(mode, length)
 
-    A = adata.encode()
-    M = plaintext.encode()
+    A = adata
+    M = plaintext
     N = [0 for byte in range(0, N_BYTES)]
     key = [byte for byte in range(0, int(key_bits/8))]
 
@@ -72,12 +72,6 @@ def mainEnc(plaintext, adata, mode=1, length=128):
         (C, tag) = lilliput_ae_1.OCB3Enc(A, M, N, A_BITS, M_BITS, key, key_bits, tweak_bits, rounds)
     if(mode == 2) :
         (C, tag) = lilliput_ae_2.SCT2Enc(A, M, N, A_BITS, M_BITS, key, key_bits, tweak_bits, rounds)
-    for block in range(0,len(C)) :
-        for byte in C[block] :
-            print("%02x "%(byte), end="")
-    for byte in tag :
-        print("%02x "%(byte), end="")
-    print()
 
     return BlockbytesMatrixToBytes(C), bytes(tag)
 
@@ -86,7 +80,7 @@ def mainDec(ciphertext, tag, adata, mode=1, length=128):
 
     (key_bits, tweak_bits, rounds) = GetParameters(mode, length)
 
-    A = adata.encode()
+    A = adata
     C = ciphertext
     N = [0 for byte in range(0, N_BYTES)]
     key = [byte for byte in range(0, int(key_bits/8))]
@@ -102,9 +96,5 @@ def mainDec(ciphertext, tag, adata, mode=1, length=128):
         M = lilliput_ae_1.OCB3Dec(A, C, N, tag, A_BITS, M_BITS, key, key_bits, tweak_bits, rounds)
     if(mode == 2) :
         M = lilliput_ae_2.SCT2Dec(A, C, N, tag, A_BITS, M_BITS, key, key_bits, tweak_bits, rounds)
-    for block in range(0,len(M)) :
-        for byte in M[block] :
-            print("%02x "%(byte), end="")
-    print()
 
-    return BlockbytesMatrixToBytes(M).decode()
+    return BlockbytesMatrixToBytes(M)
diff --git a/python/lilliput_ae_1.py b/python/lilliput_ae_1.py
index 4884518..6d060bb 100644
--- a/python/lilliput_ae_1.py
+++ b/python/lilliput_ae_1.py
@@ -277,8 +277,5 @@ def OCB3Dec(A, C, N, tag, associated_data_length_bit, message_length_bit, key, k
     (Final, M) = TreatMessageDec(C, N, key)
     tag2 = XorState(Auth, Final)
 
-    print(M)
-    print(tag2)
-
     if(tag == tag2) :
         return M