diff --git a/core/SConscript.firmware b/core/SConscript.firmware index a1ec161725..7f6844a14d 100644 --- a/core/SConscript.firmware +++ b/core/SConscript.firmware @@ -188,6 +188,7 @@ if FEATURE_FLAGS["SECP256K1_ZKP"]: 'ENABLE_MODULE_RECOVERY', 'ENABLE_MODULE_SCHNORRSIG', 'ENABLE_MODULE_EXTRAKEYS', + 'ENABLE_MODULE_ECDH', ] SOURCE_MOD_SECP256K1_ZKP = [ 'vendor/secp256k1-zkp/src/secp256k1.c', @@ -779,7 +780,7 @@ obj_program = [] obj_program.extend(env.Object(source=SOURCE_MOD)) obj_program.extend(env.Object(source=SOURCE_MOD_CRYPTO, CCFLAGS='$CCFLAGS -ftrivial-auto-var-init=zero')) if FEATURE_FLAGS["SECP256K1_ZKP"]: - obj_program.extend(env.Object(source=SOURCE_MOD_SECP256K1_ZKP, CCFLAGS='$CCFLAGS -Wno-unused-function')) + obj_program.extend(env.Object(source=SOURCE_MOD_SECP256K1_ZKP, CCFLAGS='$CCFLAGS -Wno-unused-function -Wno-maybe-uninitialized')) source_files.extend(SOURCE_MOD_SECP256K1_ZKP) obj_program.extend(env.Object(source=SOURCE_FIRMWARE)) obj_program.extend(env.Object(source=SOURCE_MICROPYTHON)) diff --git a/core/SConscript.unix b/core/SConscript.unix index 2b4adda962..288ddcbba9 100644 --- a/core/SConscript.unix +++ b/core/SConscript.unix @@ -189,6 +189,7 @@ if FEATURE_FLAGS["SECP256K1_ZKP"]: 'ENABLE_MODULE_RECOVERY', 'ENABLE_MODULE_SCHNORRSIG', 'ENABLE_MODULE_EXTRAKEYS', + 'ENABLE_MODULE_ECDH', ] SOURCE_MOD_SECP256K1_ZKP = [ 'vendor/secp256k1-zkp/src/secp256k1.c', @@ -824,7 +825,7 @@ source_files = SOURCE_MOD + SOURCE_MOD_CRYPTO + SOURCE_MICROPYTHON + SOURCE_UNIX obj_program.extend(env.Object(source=SOURCE_MOD)) obj_program.extend(env.Object(source=SOURCE_MOD_CRYPTO, CCFLAGS='$CCFLAGS -ftrivial-auto-var-init=zero')) if FEATURE_FLAGS["SECP256K1_ZKP"]: - obj_program.extend(env.Object(source=SOURCE_MOD_SECP256K1_ZKP, CCFLAGS='$CCFLAGS -Wno-unused-function')) + obj_program.extend(env.Object(source=SOURCE_MOD_SECP256K1_ZKP, CCFLAGS='$CCFLAGS -Wno-unused-function -Wno-maybe-uninitialized')) source_files.extend(SOURCE_MOD_SECP256K1_ZKP) obj_program.extend(env.Object(source=SOURCE_MICROPYTHON)) obj_program.extend(env.Object(source=SOURCE_UNIX)) diff --git a/crypto/Makefile b/crypto/Makefile index b3cd50b027..34bab1175d 100644 --- a/crypto/Makefile +++ b/crypto/Makefile @@ -69,7 +69,8 @@ ZKP_CFLAGS = \ -DENABLE_MODULE_GENERATOR \ -DENABLE_MODULE_RECOVERY \ -DENABLE_MODULE_SCHNORRSIG \ - -DENABLE_MODULE_EXTRAKEYS + -DENABLE_MODULE_EXTRAKEYS \ + -DENABLE_MODULE_ECDH ZKP_PATH = ../vendor/secp256k1-zkp # this is specific for 64-bit builds CFLAGS += -DSECP256K1_CONTEXT_SIZE=208 diff --git a/crypto/ecdsa.c b/crypto/ecdsa.c index 79fdaec670..0e3175e60c 100644 --- a/crypto/ecdsa.c +++ b/crypto/ecdsa.c @@ -635,8 +635,8 @@ int scalar_multiply(const ecdsa_curve *curve, const bignum256 *k, #endif -int ecdh_multiply(const ecdsa_curve *curve, const uint8_t *priv_key, - const uint8_t *pub_key, uint8_t *session_key) { +int tc_ecdh_multiply(const ecdsa_curve *curve, const uint8_t *priv_key, + const uint8_t *pub_key, uint8_t *session_key) { curve_point point = {0}; if (!ecdsa_read_pubkey(curve, pub_key, &point)) { return 1; @@ -1312,3 +1312,13 @@ int ecdsa_recover_pub_from_sig(const ecdsa_curve *curve, uint8_t *pub_key, #endif return tc_ecdsa_recover_pub_from_sig(curve, pub_key, sig, digest, recid); } + +int ecdh_multiply(const ecdsa_curve *curve, const uint8_t *priv_key, + const uint8_t *pub_key, uint8_t *session_key) { +#ifdef USE_SECP256K1_ZKP_ECDSA + if (curve == &secp256k1) { + return zkp_ecdh_multiply(curve, priv_key, pub_key, session_key); + } +#endif + return tc_ecdh_multiply(curve, priv_key, pub_key, session_key); +} diff --git a/crypto/ecdsa_internal.h b/crypto/ecdsa_internal.h index 6d5c98465e..0397f6250f 100644 --- a/crypto/ecdsa_internal.h +++ b/crypto/ecdsa_internal.h @@ -39,5 +39,6 @@ int tc_ecdsa_verify_digest(const ecdsa_curve *curve, const uint8_t *pub_key, int tc_ecdsa_recover_pub_from_sig(const ecdsa_curve *curve, uint8_t *pub_key, const uint8_t *sig, const uint8_t *digest, int recid); - +int tc_ecdh_multiply(const ecdsa_curve *curve, const uint8_t *priv_key, + const uint8_t *pub_key, uint8_t *session_key); #endif diff --git a/crypto/tests/test_check.c b/crypto/tests/test_check.c index 590db52396..12fb9d0d94 100644 --- a/crypto/tests/test_check.c +++ b/crypto/tests/test_check.c @@ -4426,6 +4426,90 @@ START_TEST(test_aes) { } END_TEST +static void test_ecdh_multiply_helper( + int (*ecdh_multiply_fn)(const ecdsa_curve *curve, const uint8_t *priv_key, + const uint8_t *pub_key, uint8_t *session_key)) { + static struct { + const char *priv_key; + const char *pub_key; + int res; + const char *session_key; + } tests[] = { + // Compressed public key + {"1618cc490a4a5b38d9f877759a2c312026fe9f459edb9ba49e91b6de4a237cad", + "0322c16706cd0d80dbb4e314799ba1323420e7ffa859a0cf0c82a444192bb6c997", 0, + "047b27ebb15e8197c9a560afc1bd45e2a78b864829fc1257333a1a2d7d30d79eed17889" + "8ad4960f756cf155cf46d22f2e3b21df10ee5bad560c467ae0d79427a70"}, + // Uncompressed public key + {"55b57f9ffc79d206eaa2b25dd5fe5a0be2d9d880ddfa777a3a0f9c0b2d3a191e", + "04816c5bb10c97b96a0b02382b8f8c1a8876218af04396976dace353a139752c6baef57" + "449121650cefca54cf9ac4e304890ada667512b5d98171b54a5a8347b09", + 0, + "049b3ab299d119eb89b632ff63ed0b3790508a0020fd729bbc35f39d221101ac5edc3be" + "e252886ea8f68c835ed410b715d41e967d0bd10a01a4b01eaa2320a7f4d"}, + // Invalid compressed public key + {"d2ffd4daa78a7fb253edb315e27f5841df00a581ab2c3330ffded22be98b7c96", + "026a575a9f3d4e945366a78e7961b312018451df8485ee1210767a0575225c2764", 1, + ""}, + // Invalid uncompressed public key + {"7da05844e870b1674c14a9a80b45ef36d221680707b727a7b6c70b2a25e99717", + "71ebf221ab355d070a570525e4c4bff94b27ca97e67fcdfb993f6546e7e1ead0ea09ed1" + "f7e55282f2787c7fc54cc5815660641cd95148a4b56f15818a04c7f72", + 1, ""}, + // Invalid compressed public key - the point at infinity + {"6753537e70935a9c85b0bad5b2aa54fb565b50bcf086acc7836a94318bc442d4", + "000000000000000000000000000000000000000000000000000000000000000000", 1, + ""}, + // Invalid uncompressed public key - the point at infinity + {"6753537e70935a9c85b0bad5b2aa54fb565b50bcf086acc7836a94318bc442d4", + "0000000000000000000000000000000000000000000000000000000000000000000000" + "0" + "00000000000000000000000000000000000000000000000000000000000", + 1, ""}, + // Invalid private key - the group order + {"fffffffffffffffffffffffffffffffebaaedce6af48a03bbfd25e8cd0364141", + "02e38ad3515c21358659ef113864b26e6caaa6bb780ce02daaf1c13f4fe24bb632", 2, + ""}, + // Invalid private key - zero + {"0000000000000000000000000000000000000000000000000000000000000000", + "038325242a489e883afdc86da5a714e4ffc86530e1b6660ac87ffb87c0045e486c", 2, + ""}, + }; + + const ecdsa_curve *curve = &secp256k1; + uint8_t priv_key[32] = {0}; + uint8_t pub_key[65] = {0}; + uint8_t session_key[65] = {0}; + uint8_t expected_session_key[65] = {0}; + int expected_res = 0; + int res = 0; + + for (size_t i = 0; i < sizeof(tests) / sizeof(*tests); i++) { + memcpy(priv_key, fromhex(tests[i].priv_key), 32); + memcpy(pub_key, fromhex(tests[i].pub_key), 65); + expected_res = tests[i].res; + if (expected_res == 0) { + memcpy(expected_session_key, fromhex(tests[i].session_key), 65); + } + + res = ecdh_multiply_fn(curve, priv_key, pub_key, session_key); + ck_assert_int_eq(expected_res, res); + if (expected_res == 0) { + ck_assert_mem_eq(expected_session_key, session_key, 65); + } + } +} + +START_TEST(test_tc_ecdh_multiply) { + test_ecdh_multiply_helper(tc_ecdh_multiply); +} +END_TEST + +START_TEST(test_zkp_ecdh_multiply) { + test_ecdh_multiply_helper(zkp_ecdh_multiply); +} +END_TEST + // test vectors from // https://datatracker.ietf.org/doc/html/rfc3610 // https://doi.org/10.6028/NIST.SP.800-38C @@ -11351,10 +11435,12 @@ Suite *test_suite(void) { tcase_add_test(tc, test_tc_ecdsa_get_public_key65); tcase_add_test(tc, test_tc_ecdsa_recover_pub_from_sig); tcase_add_test(tc, test_tc_ecdsa_verify_digest); + tcase_add_test(tc, test_tc_ecdh_multiply); tcase_add_test(tc, test_zkp_ecdsa_get_public_key33); tcase_add_test(tc, test_zkp_ecdsa_get_public_key65); tcase_add_test(tc, test_zkp_ecdsa_recover_pub_from_sig); tcase_add_test(tc, test_zkp_ecdsa_verify_digest); + tcase_add_test(tc, test_zkp_ecdh_multiply); #if USE_RFC6979 tcase_add_test(tc, test_tc_ecdsa_sign_digest_deterministic); tcase_add_test(tc, test_zkp_ecdsa_sign_digest_deterministic); diff --git a/crypto/zkp_ecdsa.c b/crypto/zkp_ecdsa.c index aca2c21779..b34c24a90a 100644 --- a/crypto/zkp_ecdsa.c +++ b/crypto/zkp_ecdsa.c @@ -29,6 +29,7 @@ #include "zkp_context.h" #include "vendor/secp256k1-zkp/include/secp256k1.h" +#include "vendor/secp256k1-zkp/include/secp256k1_ecdh.h" #include "vendor/secp256k1-zkp/include/secp256k1_extrakeys.h" #include "vendor/secp256k1-zkp/include/secp256k1_preallocated.h" #include "vendor/secp256k1-zkp/include/secp256k1_recovery.h" @@ -403,3 +404,79 @@ int zkp_ecdsa_verify(const ecdsa_curve *curve, HasherType hasher_type, memzero(hash, sizeof(hash)); return result; } + +static int plain_hash_function(unsigned char *output, const unsigned char *x32, + const unsigned char *y32, void *data) { + (void)data; + output[0] = 0x04; + memcpy(output + 1, x32, 32); + memcpy(output + 33, y32, 32); + return 1; +} + +// ECDH multiplication +// curve has to be &secp256k1 +// private_key_bytes has 32 bytes +// public_key_bytes has 33 or 65 bytes +// session key has 65 bytes +// returns 0 on success +int zkp_ecdh_multiply(const ecdsa_curve *curve, + const uint8_t *private_key_bytes, + const uint8_t *public_key_bytes, uint8_t *session_key) { + assert(curve == &secp256k1); + if (curve != &secp256k1) { + return 1; + } + + int result = 0; + + int public_key_length = 0; + + if (result == 0) { + if (public_key_bytes[0] == 0x04) { + public_key_length = 65; + } else if (public_key_bytes[0] == 0x02 || public_key_bytes[0] == 0x03) { + public_key_length = 33; + } else { + result = 1; + } + } + + const secp256k1_context *context_read_only = zkp_context_get_read_only(); + secp256k1_pubkey public_key = {0}; + + if (result == 0) { + if (secp256k1_ec_pubkey_parse(context_read_only, &public_key, + public_key_bytes, public_key_length) != 1) { + result = 1; + } + } + + secp256k1_context *context_writable = NULL; + if (result == 0) { + context_writable = zkp_context_acquire_writable(); + if (context_writable == NULL) { + result = 1; + } + } + if (result == 0) { + if (secp256k1_context_writable_randomize(context_writable) != 0) { + result = 1; + } + } + + if (result == 0) { + if (secp256k1_ecdh(context_writable, session_key, &public_key, + private_key_bytes, plain_hash_function, NULL) != 1) { + result = 2; + } + } + + if (context_writable) { + zkp_context_release_writable(); + context_writable = NULL; + } + memzero(&public_key, sizeof(public_key)); + + return result; +} diff --git a/crypto/zkp_ecdsa.h b/crypto/zkp_ecdsa.h index aa9b0256fe..2977eac29f 100644 --- a/crypto/zkp_ecdsa.h +++ b/crypto/zkp_ecdsa.h @@ -27,4 +27,6 @@ int zkp_ecdsa_verify_digest(const ecdsa_curve *curve, int zkp_ecdsa_verify(const ecdsa_curve *curve, HasherType hasher_sign, const uint8_t *pub_key, const uint8_t *sig, const uint8_t *msg, uint32_t msg_len); +int zkp_ecdh_multiply(const ecdsa_curve *curve, const uint8_t *priv_key, + const uint8_t *pub_key, uint8_t *session_key); #endif diff --git a/legacy/firmware/Makefile b/legacy/firmware/Makefile index a02c3f2c5e..f85ba1ab76 100644 --- a/legacy/firmware/Makefile +++ b/legacy/firmware/Makefile @@ -23,7 +23,8 @@ ZKP_CFLAGS = \ -DENABLE_MODULE_GENERATOR \ -DENABLE_MODULE_RECOVERY \ -DENABLE_MODULE_SCHNORRSIG \ - -DENABLE_MODULE_EXTRAKEYS + -DENABLE_MODULE_EXTRAKEYS \ + -DENABLE_MODULE_ECDH OBJS += secp256k1-zkp.o OBJS += precomputed_ecmult.o