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Diffstat (limited to 'src/secp256k1/src/modules/extrakeys/tests_impl.h')
-rw-r--r-- | src/secp256k1/src/modules/extrakeys/tests_impl.h | 524 |
1 files changed, 524 insertions, 0 deletions
diff --git a/src/secp256k1/src/modules/extrakeys/tests_impl.h b/src/secp256k1/src/modules/extrakeys/tests_impl.h new file mode 100644 index 0000000000..fc9d40eda1 --- /dev/null +++ b/src/secp256k1/src/modules/extrakeys/tests_impl.h @@ -0,0 +1,524 @@ +/********************************************************************** + * Copyright (c) 2020 Jonas Nick * + * Distributed under the MIT software license, see the accompanying * + * file COPYING or http://www.opensource.org/licenses/mit-license.php.* + **********************************************************************/ + +#ifndef _SECP256K1_MODULE_EXTRAKEYS_TESTS_ +#define _SECP256K1_MODULE_EXTRAKEYS_TESTS_ + +#include "secp256k1_extrakeys.h" + +static secp256k1_context* api_test_context(int flags, int *ecount) { + secp256k1_context *ctx0 = secp256k1_context_create(flags); + secp256k1_context_set_error_callback(ctx0, counting_illegal_callback_fn, ecount); + secp256k1_context_set_illegal_callback(ctx0, counting_illegal_callback_fn, ecount); + return ctx0; +} + +void test_xonly_pubkey(void) { + secp256k1_pubkey pk; + secp256k1_xonly_pubkey xonly_pk, xonly_pk_tmp; + secp256k1_ge pk1; + secp256k1_ge pk2; + secp256k1_fe y; + unsigned char sk[32]; + unsigned char xy_sk[32]; + unsigned char buf32[32]; + unsigned char ones32[32]; + unsigned char zeros64[64] = { 0 }; + int pk_parity; + int i; + + int ecount; + secp256k1_context *none = api_test_context(SECP256K1_CONTEXT_NONE, &ecount); + secp256k1_context *sign = api_test_context(SECP256K1_CONTEXT_SIGN, &ecount); + secp256k1_context *verify = api_test_context(SECP256K1_CONTEXT_VERIFY, &ecount); + + secp256k1_rand256(sk); + memset(ones32, 0xFF, 32); + secp256k1_rand256(xy_sk); + CHECK(secp256k1_ec_pubkey_create(sign, &pk, sk) == 1); + CHECK(secp256k1_xonly_pubkey_from_pubkey(none, &xonly_pk, &pk_parity, &pk) == 1); + + /* Test xonly_pubkey_from_pubkey */ + ecount = 0; + CHECK(secp256k1_xonly_pubkey_from_pubkey(none, &xonly_pk, &pk_parity, &pk) == 1); + CHECK(secp256k1_xonly_pubkey_from_pubkey(sign, &xonly_pk, &pk_parity, &pk) == 1); + CHECK(secp256k1_xonly_pubkey_from_pubkey(verify, &xonly_pk, &pk_parity, &pk) == 1); + CHECK(secp256k1_xonly_pubkey_from_pubkey(none, NULL, &pk_parity, &pk) == 0); + CHECK(ecount == 1); + CHECK(secp256k1_xonly_pubkey_from_pubkey(none, &xonly_pk, NULL, &pk) == 1); + CHECK(secp256k1_xonly_pubkey_from_pubkey(none, &xonly_pk, &pk_parity, NULL) == 0); + CHECK(ecount == 2); + memset(&pk, 0, sizeof(pk)); + CHECK(secp256k1_xonly_pubkey_from_pubkey(none, &xonly_pk, &pk_parity, &pk) == 0); + CHECK(ecount == 3); + + /* Choose a secret key such that the resulting pubkey and xonly_pubkey match. */ + memset(sk, 0, sizeof(sk)); + sk[0] = 1; + CHECK(secp256k1_ec_pubkey_create(ctx, &pk, sk) == 1); + CHECK(secp256k1_xonly_pubkey_from_pubkey(ctx, &xonly_pk, &pk_parity, &pk) == 1); + CHECK(memcmp(&pk, &xonly_pk, sizeof(pk)) == 0); + CHECK(pk_parity == 0); + + /* Choose a secret key such that pubkey and xonly_pubkey are each others + * negation. */ + sk[0] = 2; + CHECK(secp256k1_ec_pubkey_create(ctx, &pk, sk) == 1); + CHECK(secp256k1_xonly_pubkey_from_pubkey(ctx, &xonly_pk, &pk_parity, &pk) == 1); + CHECK(memcmp(&xonly_pk, &pk, sizeof(xonly_pk)) != 0); + CHECK(pk_parity == 1); + secp256k1_pubkey_load(ctx, &pk1, &pk); + secp256k1_pubkey_load(ctx, &pk2, (secp256k1_pubkey *) &xonly_pk); + CHECK(secp256k1_fe_equal(&pk1.x, &pk2.x) == 1); + secp256k1_fe_negate(&y, &pk2.y, 1); + CHECK(secp256k1_fe_equal(&pk1.y, &y) == 1); + + /* Test xonly_pubkey_serialize and xonly_pubkey_parse */ + ecount = 0; + CHECK(secp256k1_xonly_pubkey_serialize(none, NULL, &xonly_pk) == 0); + CHECK(ecount == 1); + CHECK(secp256k1_xonly_pubkey_serialize(none, buf32, NULL) == 0); + CHECK(memcmp(buf32, zeros64, 32) == 0); + CHECK(ecount == 2); + { + /* A pubkey filled with 0s will fail to serialize due to pubkey_load + * special casing. */ + secp256k1_xonly_pubkey pk_tmp; + memset(&pk_tmp, 0, sizeof(pk_tmp)); + CHECK(secp256k1_xonly_pubkey_serialize(none, buf32, &pk_tmp) == 0); + } + /* pubkey_load called illegal callback */ + CHECK(ecount == 3); + + CHECK(secp256k1_xonly_pubkey_serialize(none, buf32, &xonly_pk) == 1); + ecount = 0; + CHECK(secp256k1_xonly_pubkey_parse(none, NULL, buf32) == 0); + CHECK(ecount == 1); + CHECK(secp256k1_xonly_pubkey_parse(none, &xonly_pk, NULL) == 0); + CHECK(ecount == 2); + + /* Serialization and parse roundtrip */ + CHECK(secp256k1_xonly_pubkey_from_pubkey(none, &xonly_pk, NULL, &pk) == 1); + CHECK(secp256k1_xonly_pubkey_serialize(ctx, buf32, &xonly_pk) == 1); + CHECK(secp256k1_xonly_pubkey_parse(ctx, &xonly_pk_tmp, buf32) == 1); + CHECK(memcmp(&xonly_pk, &xonly_pk_tmp, sizeof(xonly_pk)) == 0); + + /* Test parsing invalid field elements */ + memset(&xonly_pk, 1, sizeof(xonly_pk)); + /* Overflowing field element */ + CHECK(secp256k1_xonly_pubkey_parse(none, &xonly_pk, ones32) == 0); + CHECK(memcmp(&xonly_pk, zeros64, sizeof(xonly_pk)) == 0); + memset(&xonly_pk, 1, sizeof(xonly_pk)); + /* There's no point with x-coordinate 0 on secp256k1 */ + CHECK(secp256k1_xonly_pubkey_parse(none, &xonly_pk, zeros64) == 0); + CHECK(memcmp(&xonly_pk, zeros64, sizeof(xonly_pk)) == 0); + /* If a random 32-byte string can not be parsed with ec_pubkey_parse + * (because interpreted as X coordinate it does not correspond to a point on + * the curve) then xonly_pubkey_parse should fail as well. */ + for (i = 0; i < count; i++) { + unsigned char rand33[33]; + secp256k1_rand256(&rand33[1]); + rand33[0] = SECP256K1_TAG_PUBKEY_EVEN; + if (!secp256k1_ec_pubkey_parse(ctx, &pk, rand33, 33)) { + memset(&xonly_pk, 1, sizeof(xonly_pk)); + CHECK(secp256k1_xonly_pubkey_parse(ctx, &xonly_pk, &rand33[1]) == 0); + CHECK(memcmp(&xonly_pk, zeros64, sizeof(xonly_pk)) == 0); + } else { + CHECK(secp256k1_xonly_pubkey_parse(ctx, &xonly_pk, &rand33[1]) == 1); + } + } + CHECK(ecount == 2); + + secp256k1_context_destroy(none); + secp256k1_context_destroy(sign); + secp256k1_context_destroy(verify); +} + +void test_xonly_pubkey_tweak(void) { + unsigned char zeros64[64] = { 0 }; + unsigned char overflows[32]; + unsigned char sk[32]; + secp256k1_pubkey internal_pk; + secp256k1_xonly_pubkey internal_xonly_pk; + secp256k1_pubkey output_pk; + int pk_parity; + unsigned char tweak[32]; + int i; + + int ecount; + secp256k1_context *none = api_test_context(SECP256K1_CONTEXT_NONE, &ecount); + secp256k1_context *sign = api_test_context(SECP256K1_CONTEXT_SIGN, &ecount); + secp256k1_context *verify = api_test_context(SECP256K1_CONTEXT_VERIFY, &ecount); + + memset(overflows, 0xff, sizeof(overflows)); + secp256k1_rand256(tweak); + secp256k1_rand256(sk); + CHECK(secp256k1_ec_pubkey_create(ctx, &internal_pk, sk) == 1); + CHECK(secp256k1_xonly_pubkey_from_pubkey(none, &internal_xonly_pk, &pk_parity, &internal_pk) == 1); + + ecount = 0; + CHECK(secp256k1_xonly_pubkey_tweak_add(none, &output_pk, &internal_xonly_pk, tweak) == 0); + CHECK(ecount == 1); + CHECK(secp256k1_xonly_pubkey_tweak_add(sign, &output_pk, &internal_xonly_pk, tweak) == 0); + CHECK(ecount == 2); + CHECK(secp256k1_xonly_pubkey_tweak_add(verify, &output_pk, &internal_xonly_pk, tweak) == 1); + CHECK(secp256k1_xonly_pubkey_tweak_add(verify, NULL, &internal_xonly_pk, tweak) == 0); + CHECK(ecount == 3); + CHECK(secp256k1_xonly_pubkey_tweak_add(verify, &output_pk, NULL, tweak) == 0); + CHECK(ecount == 4); + /* NULL internal_xonly_pk zeroes the output_pk */ + CHECK(memcmp(&output_pk, zeros64, sizeof(output_pk)) == 0); + CHECK(secp256k1_xonly_pubkey_tweak_add(verify, &output_pk, &internal_xonly_pk, NULL) == 0); + CHECK(ecount == 5); + /* NULL tweak zeroes the output_pk */ + CHECK(memcmp(&output_pk, zeros64, sizeof(output_pk)) == 0); + + /* Invalid tweak zeroes the output_pk */ + CHECK(secp256k1_xonly_pubkey_tweak_add(verify, &output_pk, &internal_xonly_pk, overflows) == 0); + CHECK(memcmp(&output_pk, zeros64, sizeof(output_pk)) == 0); + + /* A zero tweak is fine */ + CHECK(secp256k1_xonly_pubkey_tweak_add(verify, &output_pk, &internal_xonly_pk, zeros64) == 1); + + /* Fails if the resulting key was infinity */ + for (i = 0; i < count; i++) { + secp256k1_scalar scalar_tweak; + /* Because sk may be negated before adding, we need to try with tweak = + * sk as well as tweak = -sk. */ + secp256k1_scalar_set_b32(&scalar_tweak, sk, NULL); + secp256k1_scalar_negate(&scalar_tweak, &scalar_tweak); + secp256k1_scalar_get_b32(tweak, &scalar_tweak); + CHECK((secp256k1_xonly_pubkey_tweak_add(verify, &output_pk, &internal_xonly_pk, sk) == 0) + || (secp256k1_xonly_pubkey_tweak_add(verify, &output_pk, &internal_xonly_pk, tweak) == 0)); + CHECK(memcmp(&output_pk, zeros64, sizeof(output_pk)) == 0); + } + + /* Invalid pk with a valid tweak */ + memset(&internal_xonly_pk, 0, sizeof(internal_xonly_pk)); + secp256k1_rand256(tweak); + ecount = 0; + CHECK(secp256k1_xonly_pubkey_tweak_add(verify, &output_pk, &internal_xonly_pk, tweak) == 0); + CHECK(ecount == 1); + CHECK(memcmp(&output_pk, zeros64, sizeof(output_pk)) == 0); + + secp256k1_context_destroy(none); + secp256k1_context_destroy(sign); + secp256k1_context_destroy(verify); +} + +void test_xonly_pubkey_tweak_check(void) { + unsigned char zeros64[64] = { 0 }; + unsigned char overflows[32]; + unsigned char sk[32]; + secp256k1_pubkey internal_pk; + secp256k1_xonly_pubkey internal_xonly_pk; + secp256k1_pubkey output_pk; + secp256k1_xonly_pubkey output_xonly_pk; + unsigned char output_pk32[32]; + unsigned char buf32[32]; + int pk_parity; + unsigned char tweak[32]; + + int ecount; + secp256k1_context *none = api_test_context(SECP256K1_CONTEXT_NONE, &ecount); + secp256k1_context *sign = api_test_context(SECP256K1_CONTEXT_SIGN, &ecount); + secp256k1_context *verify = api_test_context(SECP256K1_CONTEXT_VERIFY, &ecount); + + memset(overflows, 0xff, sizeof(overflows)); + secp256k1_rand256(tweak); + secp256k1_rand256(sk); + CHECK(secp256k1_ec_pubkey_create(ctx, &internal_pk, sk) == 1); + CHECK(secp256k1_xonly_pubkey_from_pubkey(none, &internal_xonly_pk, &pk_parity, &internal_pk) == 1); + + ecount = 0; + CHECK(secp256k1_xonly_pubkey_tweak_add(verify, &output_pk, &internal_xonly_pk, tweak) == 1); + CHECK(secp256k1_xonly_pubkey_from_pubkey(verify, &output_xonly_pk, &pk_parity, &output_pk) == 1); + CHECK(secp256k1_xonly_pubkey_serialize(ctx, buf32, &output_xonly_pk) == 1); + CHECK(secp256k1_xonly_pubkey_tweak_add_check(none, buf32, pk_parity, &internal_xonly_pk, tweak) == 0); + CHECK(ecount == 1); + CHECK(secp256k1_xonly_pubkey_tweak_add_check(sign, buf32, pk_parity, &internal_xonly_pk, tweak) == 0); + CHECK(ecount == 2); + CHECK(secp256k1_xonly_pubkey_tweak_add_check(verify, buf32, pk_parity, &internal_xonly_pk, tweak) == 1); + CHECK(secp256k1_xonly_pubkey_tweak_add_check(verify, NULL, pk_parity, &internal_xonly_pk, tweak) == 0); + CHECK(ecount == 3); + /* invalid pk_parity value */ + CHECK(secp256k1_xonly_pubkey_tweak_add_check(verify, buf32, 2, &internal_xonly_pk, tweak) == 0); + CHECK(ecount == 3); + CHECK(secp256k1_xonly_pubkey_tweak_add_check(verify, buf32, pk_parity, NULL, tweak) == 0); + CHECK(ecount == 4); + CHECK(secp256k1_xonly_pubkey_tweak_add_check(verify, buf32, pk_parity, &internal_xonly_pk, NULL) == 0); + CHECK(ecount == 5); + + memset(tweak, 1, sizeof(tweak)); + CHECK(secp256k1_xonly_pubkey_from_pubkey(ctx, &internal_xonly_pk, NULL, &internal_pk) == 1); + CHECK(secp256k1_xonly_pubkey_tweak_add(ctx, &output_pk, &internal_xonly_pk, tweak) == 1); + CHECK(secp256k1_xonly_pubkey_from_pubkey(ctx, &output_xonly_pk, &pk_parity, &output_pk) == 1); + CHECK(secp256k1_xonly_pubkey_serialize(ctx, output_pk32, &output_xonly_pk) == 1); + CHECK(secp256k1_xonly_pubkey_tweak_add_check(ctx, output_pk32, pk_parity, &internal_xonly_pk, tweak) == 1); + + /* Wrong pk_parity */ + CHECK(secp256k1_xonly_pubkey_tweak_add_check(ctx, output_pk32, !pk_parity, &internal_xonly_pk, tweak) == 0); + /* Wrong public key */ + CHECK(secp256k1_xonly_pubkey_serialize(ctx, buf32, &internal_xonly_pk) == 1); + CHECK(secp256k1_xonly_pubkey_tweak_add_check(ctx, buf32, pk_parity, &internal_xonly_pk, tweak) == 0); + + /* Overflowing tweak not allowed */ + CHECK(secp256k1_xonly_pubkey_tweak_add_check(ctx, output_pk32, pk_parity, &internal_xonly_pk, overflows) == 0); + CHECK(secp256k1_xonly_pubkey_tweak_add(ctx, &output_pk, &internal_xonly_pk, overflows) == 0); + CHECK(memcmp(&output_pk, zeros64, sizeof(output_pk)) == 0); + CHECK(ecount == 5); + + secp256k1_context_destroy(none); + secp256k1_context_destroy(sign); + secp256k1_context_destroy(verify); +} + +/* Starts with an initial pubkey and recursively creates N_PUBKEYS - 1 + * additional pubkeys by calling tweak_add. Then verifies every tweak starting + * from the last pubkey. */ +#define N_PUBKEYS 32 +void test_xonly_pubkey_tweak_recursive(void) { + unsigned char sk[32]; + secp256k1_pubkey pk[N_PUBKEYS]; + unsigned char pk_serialized[32]; + unsigned char tweak[N_PUBKEYS - 1][32]; + int i; + + secp256k1_rand256(sk); + CHECK(secp256k1_ec_pubkey_create(ctx, &pk[0], sk) == 1); + /* Add tweaks */ + for (i = 0; i < N_PUBKEYS - 1; i++) { + secp256k1_xonly_pubkey xonly_pk; + memset(tweak[i], i + 1, sizeof(tweak[i])); + CHECK(secp256k1_xonly_pubkey_from_pubkey(ctx, &xonly_pk, NULL, &pk[i]) == 1); + CHECK(secp256k1_xonly_pubkey_tweak_add(ctx, &pk[i + 1], &xonly_pk, tweak[i]) == 1); + } + + /* Verify tweaks */ + for (i = N_PUBKEYS - 1; i > 0; i--) { + secp256k1_xonly_pubkey xonly_pk; + int pk_parity; + CHECK(secp256k1_xonly_pubkey_from_pubkey(ctx, &xonly_pk, &pk_parity, &pk[i]) == 1); + CHECK(secp256k1_xonly_pubkey_serialize(ctx, pk_serialized, &xonly_pk) == 1); + CHECK(secp256k1_xonly_pubkey_from_pubkey(ctx, &xonly_pk, NULL, &pk[i - 1]) == 1); + CHECK(secp256k1_xonly_pubkey_tweak_add_check(ctx, pk_serialized, pk_parity, &xonly_pk, tweak[i - 1]) == 1); + } +} +#undef N_PUBKEYS + +void test_keypair(void) { + unsigned char sk[32]; + unsigned char zeros96[96] = { 0 }; + unsigned char overflows[32]; + secp256k1_keypair keypair; + secp256k1_pubkey pk, pk_tmp; + secp256k1_xonly_pubkey xonly_pk, xonly_pk_tmp; + int pk_parity, pk_parity_tmp; + int ecount; + secp256k1_context *none = api_test_context(SECP256K1_CONTEXT_NONE, &ecount); + secp256k1_context *sign = api_test_context(SECP256K1_CONTEXT_SIGN, &ecount); + secp256k1_context *verify = api_test_context(SECP256K1_CONTEXT_VERIFY, &ecount); + + CHECK(sizeof(zeros96) == sizeof(keypair)); + memset(overflows, 0xFF, sizeof(overflows)); + + /* Test keypair_create */ + ecount = 0; + secp256k1_rand256(sk); + CHECK(secp256k1_keypair_create(none, &keypair, sk) == 0); + CHECK(memcmp(zeros96, &keypair, sizeof(keypair)) == 0); + CHECK(ecount == 1); + CHECK(secp256k1_keypair_create(verify, &keypair, sk) == 0); + CHECK(memcmp(zeros96, &keypair, sizeof(keypair)) == 0); + CHECK(ecount == 2); + CHECK(secp256k1_keypair_create(sign, &keypair, sk) == 1); + CHECK(secp256k1_keypair_create(sign, NULL, sk) == 0); + CHECK(ecount == 3); + CHECK(secp256k1_keypair_create(sign, &keypair, NULL) == 0); + CHECK(memcmp(zeros96, &keypair, sizeof(keypair)) == 0); + CHECK(ecount == 4); + + /* Invalid secret key */ + CHECK(secp256k1_keypair_create(sign, &keypair, zeros96) == 0); + CHECK(memcmp(zeros96, &keypair, sizeof(keypair)) == 0); + CHECK(secp256k1_keypair_create(sign, &keypair, overflows) == 0); + CHECK(memcmp(zeros96, &keypair, sizeof(keypair)) == 0); + + /* Test keypair_pub */ + ecount = 0; + secp256k1_rand256(sk); + CHECK(secp256k1_keypair_create(ctx, &keypair, sk) == 1); + CHECK(secp256k1_keypair_pub(none, &pk, &keypair) == 1); + CHECK(secp256k1_keypair_pub(none, NULL, &keypair) == 0); + CHECK(ecount == 1); + CHECK(secp256k1_keypair_pub(none, &pk, NULL) == 0); + CHECK(ecount == 2); + CHECK(memcmp(zeros96, &pk, sizeof(pk)) == 0); + + /* Using an invalid keypair is fine for keypair_pub */ + memset(&keypair, 0, sizeof(keypair)); + CHECK(secp256k1_keypair_pub(none, &pk, &keypair) == 1); + CHECK(memcmp(zeros96, &pk, sizeof(pk)) == 0); + + /* keypair holds the same pubkey as pubkey_create */ + CHECK(secp256k1_ec_pubkey_create(sign, &pk, sk) == 1); + CHECK(secp256k1_keypair_create(sign, &keypair, sk) == 1); + CHECK(secp256k1_keypair_pub(none, &pk_tmp, &keypair) == 1); + CHECK(memcmp(&pk, &pk_tmp, sizeof(pk)) == 0); + + /** Test keypair_xonly_pub **/ + ecount = 0; + secp256k1_rand256(sk); + CHECK(secp256k1_keypair_create(ctx, &keypair, sk) == 1); + CHECK(secp256k1_keypair_xonly_pub(none, &xonly_pk, &pk_parity, &keypair) == 1); + CHECK(secp256k1_keypair_xonly_pub(none, NULL, &pk_parity, &keypair) == 0); + CHECK(ecount == 1); + CHECK(secp256k1_keypair_xonly_pub(none, &xonly_pk, NULL, &keypair) == 1); + CHECK(secp256k1_keypair_xonly_pub(none, &xonly_pk, &pk_parity, NULL) == 0); + CHECK(ecount == 2); + CHECK(memcmp(zeros96, &xonly_pk, sizeof(xonly_pk)) == 0); + /* Using an invalid keypair will set the xonly_pk to 0 (first reset + * xonly_pk). */ + CHECK(secp256k1_keypair_xonly_pub(none, &xonly_pk, &pk_parity, &keypair) == 1); + memset(&keypair, 0, sizeof(keypair)); + CHECK(secp256k1_keypair_xonly_pub(none, &xonly_pk, &pk_parity, &keypair) == 0); + CHECK(memcmp(zeros96, &xonly_pk, sizeof(xonly_pk)) == 0); + CHECK(ecount == 3); + + /** keypair holds the same xonly pubkey as pubkey_create **/ + CHECK(secp256k1_ec_pubkey_create(sign, &pk, sk) == 1); + CHECK(secp256k1_xonly_pubkey_from_pubkey(none, &xonly_pk, &pk_parity, &pk) == 1); + CHECK(secp256k1_keypair_create(sign, &keypair, sk) == 1); + CHECK(secp256k1_keypair_xonly_pub(none, &xonly_pk_tmp, &pk_parity_tmp, &keypair) == 1); + CHECK(memcmp(&xonly_pk, &xonly_pk_tmp, sizeof(pk)) == 0); + CHECK(pk_parity == pk_parity_tmp); + + secp256k1_context_destroy(none); + secp256k1_context_destroy(sign); + secp256k1_context_destroy(verify); +} + +void test_keypair_add(void) { + unsigned char sk[32]; + secp256k1_keypair keypair; + unsigned char overflows[32]; + unsigned char zeros96[96] = { 0 }; + unsigned char tweak[32]; + int i; + int ecount = 0; + secp256k1_context *none = api_test_context(SECP256K1_CONTEXT_NONE, &ecount); + secp256k1_context *sign = api_test_context(SECP256K1_CONTEXT_SIGN, &ecount); + secp256k1_context *verify = api_test_context(SECP256K1_CONTEXT_VERIFY, &ecount); + + CHECK(sizeof(zeros96) == sizeof(keypair)); + secp256k1_rand256(sk); + secp256k1_rand256(tweak); + memset(overflows, 0xFF, 32); + CHECK(secp256k1_keypair_create(ctx, &keypair, sk) == 1); + + CHECK(secp256k1_keypair_xonly_tweak_add(none, &keypair, tweak) == 0); + CHECK(ecount == 1); + CHECK(secp256k1_keypair_xonly_tweak_add(sign, &keypair, tweak) == 0); + CHECK(ecount == 2); + CHECK(secp256k1_keypair_xonly_tweak_add(verify, &keypair, tweak) == 1); + CHECK(secp256k1_keypair_xonly_tweak_add(verify, NULL, tweak) == 0); + CHECK(ecount == 3); + CHECK(secp256k1_keypair_xonly_tweak_add(verify, &keypair, NULL) == 0); + CHECK(ecount == 4); + /* This does not set the keypair to zeroes */ + CHECK(memcmp(&keypair, zeros96, sizeof(keypair)) != 0); + + /* Invalid tweak zeroes the keypair */ + CHECK(secp256k1_keypair_create(ctx, &keypair, sk) == 1); + CHECK(secp256k1_keypair_xonly_tweak_add(ctx, &keypair, overflows) == 0); + CHECK(memcmp(&keypair, zeros96, sizeof(keypair)) == 0); + + /* A zero tweak is fine */ + CHECK(secp256k1_keypair_create(ctx, &keypair, sk) == 1); + CHECK(secp256k1_keypair_xonly_tweak_add(ctx, &keypair, zeros96) == 1); + + /* Fails if the resulting keypair was (sk=0, pk=infinity) */ + for (i = 0; i < count; i++) { + secp256k1_scalar scalar_tweak; + secp256k1_keypair keypair_tmp; + secp256k1_rand256(sk); + CHECK(secp256k1_keypair_create(ctx, &keypair, sk) == 1); + memcpy(&keypair_tmp, &keypair, sizeof(keypair)); + /* Because sk may be negated before adding, we need to try with tweak = + * sk as well as tweak = -sk. */ + secp256k1_scalar_set_b32(&scalar_tweak, sk, NULL); + secp256k1_scalar_negate(&scalar_tweak, &scalar_tweak); + secp256k1_scalar_get_b32(tweak, &scalar_tweak); + CHECK((secp256k1_keypair_xonly_tweak_add(ctx, &keypair, sk) == 0) + || (secp256k1_keypair_xonly_tweak_add(ctx, &keypair_tmp, tweak) == 0)); + CHECK(memcmp(&keypair, zeros96, sizeof(keypair)) == 0 + || memcmp(&keypair_tmp, zeros96, sizeof(keypair_tmp)) == 0); + } + + /* Invalid keypair with a valid tweak */ + memset(&keypair, 0, sizeof(keypair)); + secp256k1_rand256(tweak); + ecount = 0; + CHECK(secp256k1_keypair_xonly_tweak_add(verify, &keypair, tweak) == 0); + CHECK(ecount == 1); + CHECK(memcmp(&keypair, zeros96, sizeof(keypair)) == 0); + /* Only seckey part of keypair invalid */ + CHECK(secp256k1_keypair_create(ctx, &keypair, sk) == 1); + memset(&keypair, 0, 32); + CHECK(secp256k1_keypair_xonly_tweak_add(verify, &keypair, tweak) == 0); + CHECK(ecount == 2); + /* Only pubkey part of keypair invalid */ + CHECK(secp256k1_keypair_create(ctx, &keypair, sk) == 1); + memset(&keypair.data[32], 0, 64); + CHECK(secp256k1_keypair_xonly_tweak_add(verify, &keypair, tweak) == 0); + CHECK(ecount == 3); + + /* Check that the keypair_tweak_add implementation is correct */ + CHECK(secp256k1_keypair_create(ctx, &keypair, sk) == 1); + for (i = 0; i < count; i++) { + secp256k1_xonly_pubkey internal_pk; + secp256k1_xonly_pubkey output_pk; + secp256k1_pubkey output_pk_xy; + secp256k1_pubkey output_pk_expected; + unsigned char pk32[32]; + int pk_parity; + + secp256k1_rand256(tweak); + CHECK(secp256k1_keypair_xonly_pub(ctx, &internal_pk, NULL, &keypair) == 1); + CHECK(secp256k1_keypair_xonly_tweak_add(ctx, &keypair, tweak) == 1); + CHECK(secp256k1_keypair_xonly_pub(ctx, &output_pk, &pk_parity, &keypair) == 1); + + /* Check that it passes xonly_pubkey_tweak_add_check */ + CHECK(secp256k1_xonly_pubkey_serialize(ctx, pk32, &output_pk) == 1); + CHECK(secp256k1_xonly_pubkey_tweak_add_check(ctx, pk32, pk_parity, &internal_pk, tweak) == 1); + + /* Check that the resulting pubkey matches xonly_pubkey_tweak_add */ + CHECK(secp256k1_keypair_pub(ctx, &output_pk_xy, &keypair) == 1); + CHECK(secp256k1_xonly_pubkey_tweak_add(ctx, &output_pk_expected, &internal_pk, tweak) == 1); + CHECK(memcmp(&output_pk_xy, &output_pk_expected, sizeof(output_pk_xy)) == 0); + + /* Check that the secret key in the keypair is tweaked correctly */ + CHECK(secp256k1_ec_pubkey_create(ctx, &output_pk_expected, &keypair.data[0]) == 1); + CHECK(memcmp(&output_pk_xy, &output_pk_expected, sizeof(output_pk_xy)) == 0); + } + secp256k1_context_destroy(none); + secp256k1_context_destroy(sign); + secp256k1_context_destroy(verify); +} + +void run_extrakeys_tests(void) { + /* xonly key test cases */ + test_xonly_pubkey(); + test_xonly_pubkey_tweak(); + test_xonly_pubkey_tweak_check(); + test_xonly_pubkey_tweak_recursive(); + + /* keypair tests */ + test_keypair(); + test_keypair_add(); +} + +#endif |