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-rw-r--r--src/crypto/shen_ed25519_ref/ref10CommentedCombined/base.py65
1 files changed, 65 insertions, 0 deletions
diff --git a/src/crypto/shen_ed25519_ref/ref10CommentedCombined/base.py b/src/crypto/shen_ed25519_ref/ref10CommentedCombined/base.py
new file mode 100644
index 000000000..84accc858
--- /dev/null
+++ b/src/crypto/shen_ed25519_ref/ref10CommentedCombined/base.py
@@ -0,0 +1,65 @@
+b = 256
+q = 2**255 - 19
+l = 2**252 + 27742317777372353535851937790883648493
+
+def expmod(b,e,m):
+ if e == 0: return 1
+ t = expmod(b,e/2,m)**2 % m
+ if e & 1: t = (t*b) % m
+ return t
+
+def inv(x):
+ return expmod(x,q-2,q)
+
+d = -121665 * inv(121666)
+I = expmod(2,(q-1)/4,q)
+
+def xrecover(y):
+ xx = (y*y-1) * inv(d*y*y+1)
+ x = expmod(xx,(q+3)/8,q)
+ if (x*x - xx) % q != 0: x = (x*I) % q
+ if x % 2 != 0: x = q-x
+ return x
+
+By = 4 * inv(5)
+Bx = xrecover(By)
+B = [Bx % q,By % q]
+
+def edwards(P,Q):
+ x1 = P[0]
+ y1 = P[1]
+ x2 = Q[0]
+ y2 = Q[1]
+ x3 = (x1*y2+x2*y1) * inv(1+d*x1*x2*y1*y2)
+ y3 = (y1*y2+x1*x2) * inv(1-d*x1*x2*y1*y2)
+ return [x3 % q,y3 % q]
+
+def radix255(x):
+ x = x % q
+ if x + x > q: x -= q
+ x = [x,0,0,0,0,0,0,0,0,0]
+ bits = [26,25,26,25,26,25,26,25,26,25]
+ for i in range(9):
+ carry = (x[i] + 2**(bits[i]-1)) / 2**bits[i]
+ x[i] -= carry * 2**bits[i]
+ x[i + 1] += carry
+ result = ""
+ for i in range(9):
+ result = result+str(x[i])+","
+ result = result+str(x[9])
+ return result
+
+Bi = B
+for i in range(32):
+ print "{"
+ Bij = Bi
+ for j in range(8):
+ print " {"
+ print " {",radix255(Bij[1]+Bij[0]),"},"
+ print " {",radix255(Bij[1]-Bij[0]),"},"
+ print " {",radix255(2*d*Bij[0]*Bij[1]),"},"
+ Bij = edwards(Bij,Bi)
+ print " },"
+ print "},"
+ for k in range(8):
+ Bi = edwards(Bi,Bi)