New function mbedtls_ecp_keypair_calc_public
For when you calculate or import a private key, and then need to calculate
the public key.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/tests/suites/test_suite_ecp.data b/tests/suites/test_suite_ecp.data
index 8bf288b..01fdc47 100644
--- a/tests/suites/test_suite_ecp.data
+++ b/tests/suites/test_suite_ecp.data
@@ -529,6 +529,24 @@
depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
mbedtls_ecp_check_pub_priv:MBEDTLS_ECP_DP_SECP256R1:"37cc56d976091e5a723ec7592dff206eee7cf9069174d0ad14b5f76822596292":"4ee500d82311ffea2fd2345d5d16bd8a88c26b770d55cd8a2a0efa01c8b4edfe":MBEDTLS_ECP_DP_SECP256R1:"00f12a1320760270a83cbffd53f6031ef76a5d86c8a204f2c30ca9ebf51f0f0ea7":"37cc56d976091e5a723ec7592dff206eee7cf9069174d0ad14b5f76822596292":"4ee500d82311ffea2fd2345d5d16bd8a88c26b770d55cd8a2a0efa01c8b4edfe":MBEDTLS_ERR_ECP_BAD_INPUT_DATA
+ECP calculate public: secp256r1, good
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecp_calc_public:MBEDTLS_ECP_DP_SECP256R1:"00f12a1320760270a83cbffd53f6031ef76a5d86c8a204f2c30ca9ebf51f0f0ea7":0:"0437cc56d976091e5a723ec7592dff206eee7cf9069174d0ad14b5f768225962924ee500d82311ffea2fd2345d5d16bd8a88c26b770d55cd8a2a0efa01c8b4edff"
+
+ECP calculate public: secp256r1, private value out of range
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecp_calc_public:MBEDTLS_ECP_DP_SECP256R1:"ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff":MBEDTLS_ERR_ECP_INVALID_KEY:""
+
+# Alice's private key from rfc 7748, masked and adjusted for endianness
+# because the test function wants the little-endian representation.
+ECP calculate public: Curve25519, good
+depends_on:MBEDTLS_ECP_DP_CURVE25519_ENABLED
+ecp_calc_public:MBEDTLS_ECP_DP_CURVE25519:"6a2cb91da5fb77b12a99c0eb872f4cdf4566b25172c1163c7da518730a6d0770":0:"8520f0098930a754748b7ddcb43ef75a0dbf3a0d26381af4eba4a98eaa9b4e6a"
+
+ECP calculate public: Curve25519, private value not masked
+depends_on:MBEDTLS_ECP_DP_CURVE25519_ENABLED
+ecp_calc_public:MBEDTLS_ECP_DP_CURVE25519:"2a2cb91da5fb77b12a99c0eb872f4cdf4566b25172c1163c7da518730a6d0770":MBEDTLS_ERR_ECP_INVALID_KEY:"8520f0098930a754748b7ddcb43ef75a0dbf3a0d26381af4eba4a98eaa9b4e6a"
+
ECP gen keypair [#1]
depends_on:MBEDTLS_ECP_DP_SECP192R1_ENABLED
mbedtls_ecp_gen_keypair:MBEDTLS_ECP_DP_SECP192R1
diff --git a/tests/suites/test_suite_ecp.function b/tests/suites/test_suite_ecp.function
index 53b78d9..8c8d326 100644
--- a/tests/suites/test_suite_ecp.function
+++ b/tests/suites/test_suite_ecp.function
@@ -989,6 +989,40 @@
/* END_CASE */
/* BEGIN_CASE depends_on:MBEDTLS_ECP_C */
+void ecp_calc_public(int grp_id, data_t *private,
+ int expected_ret, data_t *expected_public)
+{
+ mbedtls_ecp_keypair key;
+ mbedtls_ecp_keypair_init(&key);
+ mbedtls_test_rnd_pseudo_info rnd_info;
+ memset(&rnd_info, 0x00, sizeof(mbedtls_test_rnd_pseudo_info));
+
+ TEST_EQUAL(mbedtls_ecp_group_load(&key.grp, grp_id), 0);
+ TEST_EQUAL(mbedtls_mpi_read_binary(&key.d, private->x, private->len), 0);
+
+ TEST_EQUAL(mbedtls_ecp_keypair_calc_public(&key,
+ &mbedtls_test_rnd_pseudo_rand, &rnd_info),
+ expected_ret);
+
+ if (expected_ret == 0) {
+ TEST_EQUAL(mbedtls_ecp_check_pub_priv(&key, &key,
+ &mbedtls_test_rnd_pseudo_rand, &rnd_info),
+ 0);
+ unsigned char buf[MBEDTLS_ECP_MAX_PT_LEN];
+ size_t length;
+ TEST_EQUAL(mbedtls_ecp_point_write_binary(&key.grp, &key.Q,
+ MBEDTLS_ECP_PF_UNCOMPRESSED,
+ &length, buf, sizeof(buf)),
+ 0);
+ ASSERT_COMPARE(expected_public->x, expected_public->len, buf, length);
+ }
+
+exit:
+ mbedtls_ecp_keypair_free(&key);
+}
+/* END_CASE */
+
+/* BEGIN_CASE depends_on:MBEDTLS_ECP_C */
void mbedtls_ecp_gen_keypair(int id)
{
mbedtls_ecp_group grp;