dkforest

commit c21eaf2ed183c526149cbe497dfd4f4f020e7067
parent 821f87dd4b5e0a0d98501448c8deec0dd19237d1
Author: n0tr1v <n0tr1v@protonmail.com>
Date:   Sun, 29 Jan 2023 20:32:11 -0800

cleanup + add doc

Diffstat:
M
cmd/torsign/torsign.py
 | 
37
+++++++++++++++++++------------------

1 file changed, 19 insertions(+), 18 deletions(-)
diff --git a/cmd/torsign/torsign.py b/cmd/torsign/torsign.py
@@ -2,6 +2,9 @@ import argparse
 import base64
 import hashlib
 
+# All the code come from onionbalance codebase
+# https://gitlab.torproject.org/tpo/core/onionbalance/-/blob/main/onionbalance/hs_v3/ext/slow_ed25519.py
+
 
 def load_tor_key_from_disk(key_bytes):
     if key_bytes[:29] != b'== ed25519v1-secret: type0 ==':
@@ -22,8 +25,13 @@ def publickeyFromESK(h):
     return encodepoint(A)
 
 
-def decodeint(s):
-    return sum(2**i * bit(s,i) for i in range(0,b))
+def signatureWithESK(m,h,pk):
+    a = decodeint(h[:32])
+    tohint = b''.join([bytes([h[i]]) for i in range(b//8,b//4)]) + m
+    r = Hint(tohint)
+    R = scalarmult(B,r)
+    S = (r + Hint(encodepoint(R) + pk + m) * a) % l
+    return encodepoint(R) + encodeint(S)
 
 
 def scalarmult(P,e):
@@ -64,15 +72,6 @@ By = 4 * inv(5)
 Bx = xrecover(By)
 B = [Bx % q,By % q]
 
-
-def encodepoint(P):
-    x = P[0]
-    y = P[1]
-    bits = [(y >> i) & 1 for i in range(b - 1)] + [x & 1]
-    return b''.join([bytes([sum([bits[i * 8 + j] << j for j in range(8)])]) for i in range(b//8)])
-
-
-
 def edwards(P,Q):
     x1 = P[0]
     y1 = P[1]
@@ -96,18 +95,20 @@ def Hint(m):
     return sum(2**i * bit(h,i) for i in range(2*b))
 
 
+def encodepoint(P):
+    x = P[0]
+    y = P[1]
+    bits = [(y >> i) & 1 for i in range(b - 1)] + [x & 1]
+    return b''.join([bytes([sum([bits[i * 8 + j] << j for j in range(8)])]) for i in range(b//8)])
+
+
 def encodeint(y):
     bits = [(y >> i) & 1 for i in range(b)]
     return b''.join([bytes([sum([bits[i * 8 + j] << j for j in range(8)])]) for i in range(b//8)])
 
 
-def signatureWithESK(m,h,pk):
-    a = decodeint(h[:32])
-    tohint = b''.join([bytes([h[i]]) for i in range(b//8,b//4)]) + m
-    r = Hint(tohint)
-    R = scalarmult(B,r)
-    S = (r + Hint(encodepoint(R) + pk + m) * a) % l
-    return encodepoint(R) + encodeint(S)
+def decodeint(s):
+    return sum(2**i * bit(s,i) for i in range(0,b))
 
 
 parser = argparse.ArgumentParser()