diff --git a/crypto/finite_field.ts b/crypto/finite_field.ts
index 99763703..1c8c88b8 100644
--- a/crypto/finite_field.ts
+++ b/crypto/finite_field.ts
@@ -195,5 +195,12 @@ function createField(p: bigint, t: bigint, twoadicRoot: bigint) {
       }
       return BigInt('0b' + binary.reverse().join(''));
     },
+    leftShift(x: bigint, bits: number, maxBitSize: number = 64) {
+      let shifted = x << BigInt(bits);
+      return shifted & ((1n << BigInt(maxBitSize)) - 1n);
+    },
+    rightShift(x: bigint, bits: number) {
+      return x >> BigInt(bits);
+    },
   };
 }