From c8dd842220a6bfbc73f1118943f8bf9cd9c0ed3b Mon Sep 17 00:00:00 2001
From: cyfraeviolae <cyfraeviolae>
Date: Fri, 26 Aug 2022 22:08:18 -0400
Subject: cache default answers

---
 .gitignore                      |  3 +--
 aesgcmanalysis.py               |  3 ---
 app.py                          | 27 +++++++++++++++++++--------
 templates/nonce-truncation.html |  2 +-
 4 files changed, 21 insertions(+), 14 deletions(-)

diff --git a/.gitignore b/.gitignore
index 22546a2..14835b2 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,5 +2,4 @@
 tmp
 venv/
 ad.np
-ad-small.np
-squares.np
+square_basis.np
diff --git a/aesgcmanalysis.py b/aesgcmanalysis.py
index 4b7e32c..338a104 100644
--- a/aesgcmanalysis.py
+++ b/aesgcmanalysis.py
@@ -795,6 +795,3 @@ def nonce_truncation_demo():
 
     h, s = nonce_truncation_recover_secrets(ct, mac, nonce, mac_bytes, aad, oracle, compute_T_once=mac_bytes==1)
     assert h == authentication_key(k)
-
-if __name__ == "__main__":
-    nonce_truncation_demo()
diff --git a/app.py b/app.py
index efc45bf..9aade4e 100644
--- a/app.py
+++ b/app.py
@@ -54,7 +54,16 @@ def solve_nonce_reuse(k, nonce, m1, m2, mf):
     c1, mac1 = gcm_encrypt(k, nonce, aad1, m1)
     c2, mac2 = gcm_encrypt(k, nonce, aad2, m2)
 
-    possible_secrets = nonce_reuse_recover_secrets(nonce, aad1, aad2, c1, c2, mac1, mac2)
+    default_m1 = 'The universe (which others call the Library)'
+    default_m2 = 'From any of the hexagons one can see, interminably'
+    if k == b'tlonorbistertius' and nonce == b'JORGELBORGES' and m1 == default_m1 and m2 == default_m2:
+        possible_secrets = [(144676297626548424623350164317265032260,
+                             137128696435097309357166918744288944691),
+                            (176085395972970454284981815262084281580,
+                             250035608282660492164551282952970544944)]
+    else:
+        possible_secrets = nonce_reuse_recover_secrets(nonce, aad1, aad2, c1, c2, mac1, mac2)
+
     c_forged = xor(c1, xor(m1, mf))
     aad_forged = b""
     macs = []
@@ -84,15 +93,17 @@ def nonce_truncation():
                            mf=mf, h=h, c_forged=c_forged, mac=mac)
 
 def solve_nonce_truncation(k, nonce, mf):
-    aad = b""
     m = secrets.token_bytes(512)
+    aad = b""
     c, mac = gcm_encrypt(k, nonce, aad, m, mac_bytes=1)
-
-    def oracle(base, aad, mac, nonce):
-        cipher = AES.new(k, mode=AES.MODE_GCM, nonce=nonce, mac_len=1)
-        cipher.update(aad)
-        cipher.decrypt_and_verify(base, mac)
-    h, s = nonce_truncation_recover_secrets(c, mac, nonce, 1, aad, oracle)
+    if k == b'tlonorbistertius' and nonce == b'JORGELBORGES':
+        h, s = 176085395972970454284981815262084281580, 48
+    else:
+        def oracle(base, aad, mac, nonce):
+            cipher = AES.new(k, mode=AES.MODE_GCM, nonce=nonce, mac_len=1)
+            cipher.update(aad)
+            cipher.decrypt_and_verify(base, mac)
+        h, s = nonce_truncation_recover_secrets(c, mac, nonce, 1, aad, oracle)
     c_forged, aad_forged = xor(c, xor(m, mf)), b""
     mac = gmac(h, s, aad_forged, c_forged)
     return gf128_to_bytes(h), c_forged, mac[:1]
diff --git a/templates/nonce-truncation.html b/templates/nonce-truncation.html
index aacaacb..0095bb1 100644
--- a/templates/nonce-truncation.html
+++ b/templates/nonce-truncation.html
@@ -108,7 +108,7 @@
         </div>
 		{% endif %}
         <br>
-		<detail>
+		<details>
 			<summary>
                 Attack outline.
 			</summary>
-- 
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