move asEC*, randomFieldElement to utils

mratsim · Aug 13, 2024 · 030f53c · 030f53c
1 parent f648d56
commit 030f53c
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Showing 2 changed files with 15 additions and 16 deletions.
diff --git a/constantine/proof_systems/constraint_systems/groth16_utils.nim b/constantine/proof_systems/constraint_systems/groth16_utils.nim
@@ -53,11 +53,21 @@ proc toEcG2*[Name: static Algebra](s: seq[byte]): EC_ShortW_Aff[Fp2[Name], G2] =
     doAssert isOnCurve(result.x, result.y, G2).bool, "Input point is not on curve!"
 
 ## Currently not used
-proc randomFieldElement*[Name: static Algebra](): Fp[Name] =
-  ## random element in ~Fp[T]~
-  let m = Fp[Name].getModulus()
-  var b: matchingBigInt(Name)
+proc randomFieldElement*[Name: static Algebra](_: typedesc[Fr[Name]]): Fr[Name] =
+  ## random element in ~Fr[Name]~
+  let m = Fr[Name].getModulus()
+  var b: matchingOrderBigInt(Name)
 
-  while b.isZero().bool or (b > m).bool:
+  while b.isZero().bool or (b > m).bool: ## XXX: or just truncate?
     assert b.limbs.sysrand()
   result.fromBig(b)
+
+proc asEC*[Name: static Algebra](pts: seq[seq[byte]], _: typedesc[Fp[Name]]): seq[EC_ShortW_Aff[Fp[Name], G1]] =
+  result = newSeq[EC_ShortW_Aff[Fp[Name], G1]](pts.len)
+  for i, el in pts:
+    result[i] = toEcG1[Name](el)
+
+proc asEC2*[Name: static Algebra](pts: seq[seq[byte]], _: typedesc[Fp2[Name]]): seq[EC_ShortW_Aff[Fp2[Name], G2]] =
+  result = newSeq[EC_ShortW_Aff[Fp2[Name], G2]](pts.len)
+  for i, el in pts:
+    result[i] = toEcG2[Name](el)
diff --git a/constantine/proof_systems/constraint_systems/manual_groth16.nim b/constantine/proof_systems/constraint_systems/manual_groth16.nim
@@ -50,17 +50,6 @@ proc getWitnesses[Name: static Algebra](ctx: Groth16Prover[Name]): seq[Fr[Name]]
   for i, w in witnesses:
     result[i] = toFr[Name](w.data, isMont = false) ## Improtant: Witness does *not* store numbers in Montgomery rep
 
-proc asEC[Name: static Algebra](pts: seq[seq[byte]], _: typedesc[Fp[Name]]): seq[EC_ShortW_Aff[Fp[Name], G1]] =
-  result = newSeq[EC_ShortW_Aff[Fp[Name], G1]](pts.len)
-  for i, el in pts:
-    result[i] = toEcG1[Name](el)
-
-proc asEC2[Name: static Algebra](pts: seq[seq[byte]], _: typedesc[Fp2[Name]]): seq[EC_ShortW_Aff[Fp2[Name], G2]] =
-  result = newSeq[EC_ShortW_Aff[Fp2[Name], G2]](pts.len)
-  for i, el in pts:
-    result[i] = toEcG2[Name](el)
-
-
 proc calcAp[Name: static Algebra](ctx: Groth16Prover[Name], wt: seq[Fr[Name]]): EC_ShortW_Jac[Fp[Name], G1] =
   # A_p is defined as
   # A_p = α_1 + (Σ_i [W]_i · A_i) + [r] · δ_1