Merge pull request #7184 from gabor-mezei-arm/6349_Secp224r1_fast_reduction

Extract Secp224r1 fast reduction from the prototype

scripts/mbedtls_dev/bignum_common.py

@@ -74,6 +74,10 @@ def combination_pairs(values: List[T]) -> List[Tuple[T, T]]:
     """Return all pair combinations from input values."""
     return [(x, y) for x in values for y in values]
 
+def hex_digits_for_limb(limbs: int, bits_in_limb: int) -> int:
+    """ Retrun the hex digits need for a number of limbs. """
+    return 2 * (limbs * bits_in_limb // 8)
+
 class OperationCommon(test_data_generation.BaseTest):
     """Common features for bignum binary operations.
 
@@ -138,7 +142,7 @@ class OperationCommon(test_data_generation.BaseTest):
 
     @property
     def hex_digits(self) -> int:
-        return 2 * (self.limbs * self.bits_in_limb // 8)
+        return hex_digits_for_limb(self.limbs, self.bits_in_limb)
 
     def format_arg(self, val: str) -> str:
         if self.input_style not in self.input_styles:

scripts/mbedtls_dev/ecp.py

@@ -19,11 +19,13 @@ from typing import List
 from . import test_data_generation
 from . import bignum_common
 
+
 class EcpTarget(test_data_generation.BaseTarget):
     #pylint: disable=abstract-method, too-few-public-methods
     """Target for ecp test case generation."""
     target_basename = 'test_suite_ecp.generated'
 
+
 class EcpP192R1Raw(bignum_common.ModOperationCommon,
                    EcpTarget):
     """Test cases for ecp quasi_reduction()."""
@@ -76,6 +78,73 @@ class EcpP192R1Raw(bignum_common.ModOperationCommon,
     def is_valid(self) -> bool:
         return True
 
+
+class EcpP224R1Raw(bignum_common.ModOperationCommon,
+                   EcpTarget):
+    """Test cases for ecp quasi_reduction()."""
+    symbol = "-"
+    test_function = "ecp_mod_p224_raw"
+    test_name = "ecp_mod_p224_raw"
+    input_style = "arch_split"
+    arity = 1
+
+    moduli = ["ffffffffffffffffffffffffffffffff000000000000000000000001"] # type: List[str]
+
+    input_values = [
+        "0", "1",
+
+        # Modulus - 1
+        "ffffffffffffffffffffffffffffffff000000000000000000000000",
+
+        # Maximum canonical P224 multiplication result
+        ("fffffffffffffffffffffffffffffffe000000000000000000000000"
+         "00000001000000000000000000000000000000000000000000000000"),
+
+        # Generate an overflow during reduction
+        ("00000000000000000000000000010000000070000000002000001000"
+         "ffffffffffff9fffffffffe00000efff000070000000002000001003"),
+
+        # Generate an underflow during reduction
+        ("00000001000000000000000000000000000000000000000000000000"
+         "00000000000dc0000000000000000001000000010000000100000003"),
+
+        # First 8 number generated by random.getrandbits(448) - seed(2,2)
+        ("da94e3e8ab73738fcf1822ffbc6887782b491044d5e341245c6e4337"
+         "15ba2bdd177219d30e7a269fd95bafc8f2a4d27bdcf4bb99f4bea973"),
+        ("cdbd47d364be8049a372db8f6e405d93ffed9235288bc781ae662675"
+         "94c9c9500925e4749b575bd13653f8dd9b1f282e4067c3584ee207f8"),
+        ("defc044a09325626e6b58de744ab6cce80877b6f71e1f6d2ef8acd12"
+         "8b4f2fc15f3f57ebf30b94fa82523e86feac7eb7dc38f519b91751da"),
+        ("2d6c797f8f7d9b782a1be9cd8697bbd0e2520e33e44c50556c71c4a6"
+         "6148a86fe8624fab5186ee32ee8d7ee9770348a05d300cb90706a045"),
+        ("8f54f8ceacaab39e83844b40ffa9b9f15c14bc4a829e07b0829a48d4"
+         "22fe99a22c70501e533c91352d3d854e061b90303b08c6e33c729578"),
+        ("97eeab64ca2ce6bc5d3fd983c34c769fe89204e2e8168561867e5e15"
+         "bc01bfce6a27e0dfcbf8754472154e76e4c11ab2fec3f6b32e8d4b8a"),
+        ("a7a83ee0761ebfd2bd143fa9b714210c665d7435c1066932f4767f26"
+         "294365b2721dea3bf63f23d0dbe53fcafb2147df5ca495fa5a91c89b"),
+        ("74667bffe202849da9643a295a9ac6decbd4d3e2d4dec9ef83f0be4e"
+         "80371eb97f81375eecc1cb6347733e847d718d733ff98ff387c56473"),
+
+        # Next 2 number generated by random.getrandbits(224)
+        "eb9ac688b9d39cca91551e8259cc60b17604e4b4e73695c3e652c71a",
+        "f0caeef038c89b38a8acb5137c9260dc74e088a9b9492f258ebdbfe3"
+    ]
+
+    @property
+    def arg_a(self) -> str:
+        hex_digits = bignum_common.hex_digits_for_limb(448 // self.bits_in_limb, self.bits_in_limb)
+        return super().format_arg('{:x}'.format(self.int_a)).zfill(hex_digits)
+
+    def result(self) -> List[str]:
+        result = self.int_a % self.int_n
+        return [self.format_result(result)]
+
+    @property
+    def is_valid(self) -> bool:
+        return True
+
+
 class EcpP521R1Raw(bignum_common.ModOperationCommon,
                    EcpTarget):
     """Test cases for ecp quasi_reduction()."""