Add unit tests for ecp_mod_p192k1()

library/ecp_curves.c

@@ -4608,6 +4608,8 @@ static int ecp_mod_p448(mbedtls_mpi *);
 #endif
 #if defined(MBEDTLS_ECP_DP_SECP192K1_ENABLED)
 static int ecp_mod_p192k1(mbedtls_mpi *);
+MBEDTLS_STATIC_TESTABLE
+int mbedtls_ecp_mod_p192k1(mbedtls_mpi *);
 #endif
 #if defined(MBEDTLS_ECP_DP_SECP224K1_ENABLED)
 static int ecp_mod_p224k1(mbedtls_mpi *);
@@ -5604,6 +5606,12 @@ static inline int ecp_mod_koblitz(mbedtls_mpi *N, mbedtls_mpi_uint *Rp, size_t p
  * with R = 2^32 + 2^12 + 2^8 + 2^7 + 2^6 + 2^3 + 1 = 0x0100001119
  */
 static int ecp_mod_p192k1(mbedtls_mpi *N)
+{
+    return mbedtls_ecp_mod_p192k1(N);
+}
+
+MBEDTLS_STATIC_TESTABLE
+int mbedtls_ecp_mod_p192k1(mbedtls_mpi *N)
 {
     static mbedtls_mpi_uint Rp[] = {
         MBEDTLS_BYTES_TO_T_UINT_8(0xC9, 0x11, 0x00, 0x00, 0x01, 0x00, 0x00,

library/ecp_invasive.h

@@ -169,6 +169,17 @@ int  mbedtls_ecp_mod_p384_raw(mbedtls_mpi_uint *X, size_t X_limbs);
 
 #endif /* MBEDTLS_ECP_DP_SECP384R1_ENABLED */
 
+#if defined(MBEDTLS_ECP_DP_SECP192K1_ENABLED)
+
+/*
+ * Fast quasi-reduction modulo p192k1 = 2^192 - R,
+ * with R = 2^32 + 2^12 + 2^8 + 2^7 + 2^6 + 2^3 + 1 = 0x0100001119
+ */
+MBEDTLS_STATIC_TESTABLE
+int mbedtls_ecp_mod_p192k1(mbedtls_mpi *N);
+
+#endif /* MBEDTLS_ECP_DP_SECP192K1_ENABLED */
+
 /** Initialise a modulus with hard-coded const curve data.
  *
  * \note            The caller is responsible for the \p N modulus' memory.

scripts/mbedtls_dev/ecp.py

@@ -488,3 +488,67 @@ def is_valid(self) -> bool:
     def arguments(self):
         args = super().arguments()
         return  ["MBEDTLS_ECP_DP_SECP521R1"] + args
+
+
+class EcpP192K1Raw(bignum_common.ModOperationCommon,
+                   EcpTarget):
+    """Test cases for ECP P192K1 fast reduction."""
+    symbol = "-"
+    test_function = "ecp_mod_p192k1"
+    test_name = "ecp_mod_p192k1"
+    input_style = "fixed"
+    arity = 1
+    dependencies = ["MBEDTLS_ECP_DP_SECP192K1_ENABLED"]
+
+    moduli = ["fffffffffffffffffffffffffffffffffffffffeffffee37"] # type: List[str]
+
+    input_values = [
+        "0", "1",
+
+        # Modulus - 1
+        "fffffffffffffffffffffffffffffffffffffffeffffee36",
+
+        # Modulus + 1
+        "fffffffffffffffffffffffffffffffffffffffeffffee38",
+
+        # 2^192 - 1
+        "ffffffffffffffffffffffffffffffffffffffffffffffff",
+
+        # Maximum canonical P192K1 multiplication result
+        ("fffffffffffffffffffffffffffffffffffffffdffffdc6c"
+         "0000000000000000000000000000000100002394013c7364"),
+
+        # First 8 number generated by random.getrandbits(384) - seed(2,2)
+        ("cf1822ffbc6887782b491044d5e341245c6e433715ba2bdd"
+         "177219d30e7a269fd95bafc8f2a4d27bdcf4bb99f4bea973"),
+        ("ffed9235288bc781ae66267594c9c9500925e4749b575bd1"
+         "3653f8dd9b1f282e4067c3584ee207f8da94e3e8ab73738f"),
+        ("ef8acd128b4f2fc15f3f57ebf30b94fa82523e86feac7eb7"
+         "dc38f519b91751dacdbd47d364be8049a372db8f6e405d93"),
+        ("e8624fab5186ee32ee8d7ee9770348a05d300cb90706a045"
+         "defc044a09325626e6b58de744ab6cce80877b6f71e1f6d2"),
+        ("2d3d854e061b90303b08c6e33c7295782d6c797f8f7d9b78"
+         "2a1be9cd8697bbd0e2520e33e44c50556c71c4a66148a86f"),
+        ("fec3f6b32e8d4b8a8f54f8ceacaab39e83844b40ffa9b9f1"
+         "5c14bc4a829e07b0829a48d422fe99a22c70501e533c9135"),
+        ("97eeab64ca2ce6bc5d3fd983c34c769fe89204e2e8168561"
+         "867e5e15bc01bfce6a27e0dfcbf8754472154e76e4c11ab2"),
+        ("bd143fa9b714210c665d7435c1066932f4767f26294365b2"
+         "721dea3bf63f23d0dbe53fcafb2147df5ca495fa5a91c89b"),
+
+        # Next 2 number generated by random.getrandbits(192)
+        "47733e847d718d733ff98ff387c56473a7a83ee0761ebfd2",
+        "cbd4d3e2d4dec9ef83f0be4e80371eb97f81375eecc1cb63"
+    ]
+
+    @property
+    def arg_a(self) -> str:
+        return super().format_arg('{:x}'.format(self.int_a)).zfill(2 * self.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

tests/suites/test_suite_ecp.function

@@ -1355,6 +1355,45 @@ exit:
 }
 /* END_CASE */
 
+/* BEGIN_CASE depends_on:MBEDTLS_TEST_HOOKS:MBEDTLS_ECP_DP_SECP192K1_ENABLED */
+void ecp_mod_p192k1(char *input_N,
+                    char *input_X,
+                    char *result)
+{
+    mbedtls_mpi X;
+    mbedtls_mpi N;
+    mbedtls_mpi res;
+
+    mbedtls_mpi_init(&X);
+    mbedtls_mpi_init(&N);
+    mbedtls_mpi_init(&res);
+
+    TEST_EQUAL(mbedtls_test_read_mpi(&X,   input_X), 0);
+    TEST_EQUAL(mbedtls_test_read_mpi(&N,   input_N), 0);
+    TEST_EQUAL(mbedtls_test_read_mpi(&res, result),  0);
+
+    TEST_ASSERT(mbedtls_mpi_core_uint_le_mpi(0, X.p, X.n));
+    TEST_ASSERT(mbedtls_mpi_core_uint_le_mpi(0, N.p, N.n));
+    TEST_ASSERT(mbedtls_mpi_core_uint_le_mpi(0, res.p, res.n));
+
+    size_t limbs = N.n;
+    size_t bytes = limbs * sizeof(mbedtls_mpi_uint);
+
+    TEST_EQUAL(X.n, 2 * limbs);
+    TEST_EQUAL(res.n, limbs);
+
+    TEST_EQUAL(mbedtls_ecp_mod_p192k1(&X), 0);
+    TEST_EQUAL(mbedtls_mpi_mod_mpi(&X, &X, &N), 0);
+    TEST_LE_U(mbedtls_mpi_core_bitlen(X.p, X.n), 192);
+    ASSERT_COMPARE(X.p, bytes, res.p, bytes);
+
+exit:
+    mbedtls_mpi_free(&X);
+    mbedtls_mpi_free(&N);
+    mbedtls_mpi_free(&res);
+}
+/* END_CASE */
+
 /* BEGIN_CASE depends_on:MBEDTLS_TEST_HOOKS */
 void ecp_mod_setup(char *input_A, int id, int ctype, int iret)
 {