[Nym3-commit] r14 - trunk/crypto

[nym3-devel@lists.noreply.org]

Author: weasel
Date: 2004-05-02 23:14:27 +0200 (Sun, 02 May 2004)
New Revision: 14

Modified:
   trunk/crypto/crypto.ml
   trunk/crypto/test_weasel.ml
Log:
prng and encrypt work now.  does that make the counter module obsolete since I do not use it?

Modified: trunk/crypto/crypto.ml
===================================================================
--- trunk/crypto/crypto.ml	2004-05-02 20:25:26 UTC (rev 13)
+++ trunk/crypto/crypto.ml	2004-05-02 21:14:27 UTC (rev 14)
@@ -112,11 +112,25 @@
  *)
 let prng n k =
   assert ((String.length k) = 16);
-  let m = String.make n (char_of_int 0)
-  and enc = aes ~mode:(OFB 1) ~iv:(String.make 16 (char_of_int 0))
-	     k Encrypt in
-  transform_string enc m
+  let result = ref ("") in
+  let block = String.make 16 (char_of_int 0) in
 
+  let n = ref n
+  and p = ref 0 in
+  while (!n > 0) do
+    String.set block (String.length block - 1) (char_of_int !p);
+    incr p;
+
+    let enc = aes k Encrypt in
+    let encrypted = transform_string enc block in
+      if (!n >= 16) then
+	result := !result ^ encrypted
+      else
+	result := !result ^ (String.sub encrypted 0 !n);
+    n := !n - 16
+  done;
+  !result
+
 (**
  * Encrypt a message <code>m</code> using AES counter mode with key <code>k</code>.
  *

Modified: trunk/crypto/test_weasel.ml
===================================================================
--- trunk/crypto/test_weasel.ml	2004-05-02 20:25:26 UTC (rev 13)
+++ trunk/crypto/test_weasel.ml	2004-05-02 21:14:27 UTC (rev 14)
@@ -41,12 +41,10 @@
 		"81 AE AE FB 58 E0 A2 FE 37 27 31 8E 5B C4 90 B9
 		86 99 95 78 C0 F6 BC AC 9A A6 16 DF BA 0B 4E 6C 0A 10 C5 8F 7B 67 54 19 D7 EA
 		8C 4A A7 0E C7 77 6B 25 51 68 88 1C 7C 4D EB 83 8C A0 3F 4A 85 32" in
-	let keystream0 = Crypto.prng 0x40 key in
-	(* and keystream0 = Crypto.prng key 0x300 in *)
+	let keystream0 = Crypto.prng 0x300 key in
 
-	Printf.printf "\n%s\n%s\n" (hex keystream1) (hex keystream0);
-	assert(keystream0 = keystream1);
-	(*assert(keystream0[0x2c0..0x40] = keystream2); *)
+	assert( (String.sub keystream0 0     0x40) = keystream1);
+	assert( (String.sub keystream0 0x2c0 0x40) = keystream2);
 	Printf.printf "."
 
 let testEncrypt =
@@ -100,6 +98,8 @@
 
 let _ = 
 	testHash;
+	testPRNG;
+	testEncrypt;
 	testSPRPEncrypt;
 	testSPRPDecrypt;
 	Printf.printf "\n"