diff options
Diffstat (limited to 'bip-0340')
-rw-r--r-- | bip-0340/reference.py | 221 | ||||
-rw-r--r-- | bip-0340/test-vectors.csv | 20 | ||||
-rw-r--r-- | bip-0340/test-vectors.py | 300 |
3 files changed, 541 insertions, 0 deletions
diff --git a/bip-0340/reference.py b/bip-0340/reference.py new file mode 100644 index 0000000..b327e0a --- /dev/null +++ b/bip-0340/reference.py @@ -0,0 +1,221 @@ +from typing import Tuple, Optional, Any +import hashlib +import binascii + +# Set DEBUG to True to get a detailed debug output including +# intermediate values during key generation, signing, and +# verification. This is implemented via calls to the +# debug_print_vars() function. +# +# If you want to print values on an individual basis, use +# the pretty() function, e.g., print(pretty(foo)). +DEBUG = False + +p = 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFC2F +n = 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 + +# Points are tuples of X and Y coordinates and the point at infinity is +# represented by the None keyword. +G = (0x79BE667EF9DCBBAC55A06295CE870B07029BFCDB2DCE28D959F2815B16F81798, 0x483ADA7726A3C4655DA4FBFC0E1108A8FD17B448A68554199C47D08FFB10D4B8) + +Point = Tuple[int, int] + +# This implementation can be sped up by storing the midstate after hashing +# tag_hash instead of rehashing it all the time. +def tagged_hash(tag: str, msg: bytes) -> bytes: + tag_hash = hashlib.sha256(tag.encode()).digest() + return hashlib.sha256(tag_hash + tag_hash + msg).digest() + +def is_infinite(P: Optional[Point]) -> bool: + return P is None + +def x(P: Point) -> int: + assert not is_infinite(P) + return P[0] + +def y(P: Point) -> int: + assert not is_infinite(P) + return P[1] + +def point_add(P1: Optional[Point], P2: Optional[Point]) -> Optional[Point]: + if P1 is None: + return P2 + if P2 is None: + return P1 + if (x(P1) == x(P2)) and (y(P1) != y(P2)): + return None + if P1 == P2: + lam = (3 * x(P1) * x(P1) * pow(2 * y(P1), p - 2, p)) % p + else: + lam = ((y(P2) - y(P1)) * pow(x(P2) - x(P1), p - 2, p)) % p + x3 = (lam * lam - x(P1) - x(P2)) % p + return (x3, (lam * (x(P1) - x3) - y(P1)) % p) + +def point_mul(P: Optional[Point], n: int) -> Optional[Point]: + R = None + for i in range(256): + if (n >> i) & 1: + R = point_add(R, P) + P = point_add(P, P) + return R + +def bytes_from_int(x: int) -> bytes: + return x.to_bytes(32, byteorder="big") + +def bytes_from_point(P: Point) -> bytes: + return bytes_from_int(x(P)) + +def xor_bytes(b0: bytes, b1: bytes) -> bytes: + return bytes(x ^ y for (x, y) in zip(b0, b1)) + +def lift_x(x: int) -> Optional[Point]: + if x >= p: + return None + y_sq = (pow(x, 3, p) + 7) % p + y = pow(y_sq, (p + 1) // 4, p) + if pow(y, 2, p) != y_sq: + return None + return (x, y if y & 1 == 0 else p-y) + +def int_from_bytes(b: bytes) -> int: + return int.from_bytes(b, byteorder="big") + +def hash_sha256(b: bytes) -> bytes: + return hashlib.sha256(b).digest() + +def has_even_y(P: Point) -> bool: + assert not is_infinite(P) + return y(P) % 2 == 0 + +def pubkey_gen(seckey: bytes) -> bytes: + d0 = int_from_bytes(seckey) + if not (1 <= d0 <= n - 1): + raise ValueError('The secret key must be an integer in the range 1..n-1.') + P = point_mul(G, d0) + assert P is not None + return bytes_from_point(P) + +def schnorr_sign(msg: bytes, seckey: bytes, aux_rand: bytes) -> bytes: + d0 = int_from_bytes(seckey) + if not (1 <= d0 <= n - 1): + raise ValueError('The secret key must be an integer in the range 1..n-1.') + if len(aux_rand) != 32: + raise ValueError('aux_rand must be 32 bytes instead of %i.' % len(aux_rand)) + P = point_mul(G, d0) + assert P is not None + d = d0 if has_even_y(P) else n - d0 + t = xor_bytes(bytes_from_int(d), tagged_hash("BIP0340/aux", aux_rand)) + k0 = int_from_bytes(tagged_hash("BIP0340/nonce", t + bytes_from_point(P) + msg)) % n + if k0 == 0: + raise RuntimeError('Failure. This happens only with negligible probability.') + R = point_mul(G, k0) + assert R is not None + k = n - k0 if not has_even_y(R) else k0 + e = int_from_bytes(tagged_hash("BIP0340/challenge", bytes_from_point(R) + bytes_from_point(P) + msg)) % n + sig = bytes_from_point(R) + bytes_from_int((k + e * d) % n) + debug_print_vars() + if not schnorr_verify(msg, bytes_from_point(P), sig): + raise RuntimeError('The created signature does not pass verification.') + return sig + +def schnorr_verify(msg: bytes, pubkey: bytes, sig: bytes) -> bool: + if len(pubkey) != 32: + raise ValueError('The public key must be a 32-byte array.') + if len(sig) != 64: + raise ValueError('The signature must be a 64-byte array.') + P = lift_x(int_from_bytes(pubkey)) + r = int_from_bytes(sig[0:32]) + s = int_from_bytes(sig[32:64]) + if (P is None) or (r >= p) or (s >= n): + debug_print_vars() + return False + e = int_from_bytes(tagged_hash("BIP0340/challenge", sig[0:32] + pubkey + msg)) % n + R = point_add(point_mul(G, s), point_mul(P, n - e)) + if (R is None) or (not has_even_y(R)) or (x(R) != r): + debug_print_vars() + return False + debug_print_vars() + return True + +# +# The following code is only used to verify the test vectors. +# +import csv +import os +import sys + +def test_vectors() -> bool: + all_passed = True + with open(os.path.join(sys.path[0], 'test-vectors.csv'), newline='') as csvfile: + reader = csv.reader(csvfile) + reader.__next__() + for row in reader: + (index, seckey_hex, pubkey_hex, aux_rand_hex, msg_hex, sig_hex, result_str, comment) = row + pubkey = bytes.fromhex(pubkey_hex) + msg = bytes.fromhex(msg_hex) + sig = bytes.fromhex(sig_hex) + result = result_str == 'TRUE' + print('\nTest vector', ('#' + index).rjust(3, ' ') + ':') + if seckey_hex != '': + seckey = bytes.fromhex(seckey_hex) + pubkey_actual = pubkey_gen(seckey) + if pubkey != pubkey_actual: + print(' * Failed key generation.') + print(' Expected key:', pubkey.hex().upper()) + print(' Actual key:', pubkey_actual.hex().upper()) + aux_rand = bytes.fromhex(aux_rand_hex) + try: + sig_actual = schnorr_sign(msg, seckey, aux_rand) + if sig == sig_actual: + print(' * Passed signing test.') + else: + print(' * Failed signing test.') + print(' Expected signature:', sig.hex().upper()) + print(' Actual signature:', sig_actual.hex().upper()) + all_passed = False + except RuntimeError as e: + print(' * Signing test raised exception:', e) + all_passed = False + result_actual = schnorr_verify(msg, pubkey, sig) + if result == result_actual: + print(' * Passed verification test.') + else: + print(' * Failed verification test.') + print(' Expected verification result:', result) + print(' Actual verification result:', result_actual) + if comment: + print(' Comment:', comment) + all_passed = False + print() + if all_passed: + print('All test vectors passed.') + else: + print('Some test vectors failed.') + return all_passed + +# +# The following code is only used for debugging +# +import inspect + +def pretty(v: Any) -> Any: + if isinstance(v, bytes): + return '0x' + v.hex() + if isinstance(v, int): + return pretty(bytes_from_int(v)) + if isinstance(v, tuple): + return tuple(map(pretty, v)) + return v + +def debug_print_vars() -> None: + if DEBUG: + current_frame = inspect.currentframe() + assert current_frame is not None + frame = current_frame.f_back + assert frame is not None + print(' Variables in function ', frame.f_code.co_name, ' at line ', frame.f_lineno, ':', sep='') + for var_name, var_val in frame.f_locals.items(): + print(' ' + var_name.rjust(11, ' '), '==', pretty(var_val)) + +if __name__ == '__main__': + test_vectors() diff --git a/bip-0340/test-vectors.csv b/bip-0340/test-vectors.csv new file mode 100644 index 0000000..6723391 --- /dev/null +++ b/bip-0340/test-vectors.csv @@ -0,0 +1,20 @@ +index,secret key,public key,aux_rand,message,signature,verification result,comment
+0,0000000000000000000000000000000000000000000000000000000000000003,F9308A019258C31049344F85F89D5229B531C845836F99B08601F113BCE036F9,0000000000000000000000000000000000000000000000000000000000000000,0000000000000000000000000000000000000000000000000000000000000000,E907831F80848D1069A5371B402410364BDF1C5F8307B0084C55F1CE2DCA821525F66A4A85EA8B71E482A74F382D2CE5EBEEE8FDB2172F477DF4900D310536C0,TRUE,
+1,B7E151628AED2A6ABF7158809CF4F3C762E7160F38B4DA56A784D9045190CFEF,DFF1D77F2A671C5F36183726DB2341BE58FEAE1DA2DECED843240F7B502BA659,0000000000000000000000000000000000000000000000000000000000000001,243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89,6896BD60EEAE296DB48A229FF71DFE071BDE413E6D43F917DC8DCF8C78DE33418906D11AC976ABCCB20B091292BFF4EA897EFCB639EA871CFA95F6DE339E4B0A,TRUE,
+2,C90FDAA22168C234C4C6628B80DC1CD129024E088A67CC74020BBEA63B14E5C9,DD308AFEC5777E13121FA72B9CC1B7CC0139715309B086C960E18FD969774EB8,C87AA53824B4D7AE2EB035A2B5BBBCCC080E76CDC6D1692C4B0B62D798E6D906,7E2D58D8B3BCDF1ABADEC7829054F90DDA9805AAB56C77333024B9D0A508B75C,5831AAEED7B44BB74E5EAB94BA9D4294C49BCF2A60728D8B4C200F50DD313C1BAB745879A5AD954A72C45A91C3A51D3C7ADEA98D82F8481E0E1E03674A6F3FB7,TRUE,
+3,0B432B2677937381AEF05BB02A66ECD012773062CF3FA2549E44F58ED2401710,25D1DFF95105F5253C4022F628A996AD3A0D95FBF21D468A1B33F8C160D8F517,FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF,FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF,7EB0509757E246F19449885651611CB965ECC1A187DD51B64FDA1EDC9637D5EC97582B9CB13DB3933705B32BA982AF5AF25FD78881EBB32771FC5922EFC66EA3,TRUE,test fails if msg is reduced modulo p or n
+4,,D69C3509BB99E412E68B0FE8544E72837DFA30746D8BE2AA65975F29D22DC7B9,,4DF3C3F68FCC83B27E9D42C90431A72499F17875C81A599B566C9889B9696703,00000000000000000000003B78CE563F89A0ED9414F5AA28AD0D96D6795F9C6376AFB1548AF603B3EB45C9F8207DEE1060CB71C04E80F593060B07D28308D7F4,TRUE,
+5,,EEFDEA4CDB677750A420FEE807EACF21EB9898AE79B9768766E4FAA04A2D4A34,,243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89,6CFF5C3BA86C69EA4B7376F31A9BCB4F74C1976089B2D9963DA2E5543E17776969E89B4C5564D00349106B8497785DD7D1D713A8AE82B32FA79D5F7FC407D39B,FALSE,public key not on the curve
+6,,DFF1D77F2A671C5F36183726DB2341BE58FEAE1DA2DECED843240F7B502BA659,,243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89,FFF97BD5755EEEA420453A14355235D382F6472F8568A18B2F057A14602975563CC27944640AC607CD107AE10923D9EF7A73C643E166BE5EBEAFA34B1AC553E2,FALSE,has_even_y(R) is false
+7,,DFF1D77F2A671C5F36183726DB2341BE58FEAE1DA2DECED843240F7B502BA659,,243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89,1FA62E331EDBC21C394792D2AB1100A7B432B013DF3F6FF4F99FCB33E0E1515F28890B3EDB6E7189B630448B515CE4F8622A954CFE545735AAEA5134FCCDB2BD,FALSE,negated message
+8,,DFF1D77F2A671C5F36183726DB2341BE58FEAE1DA2DECED843240F7B502BA659,,243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89,6CFF5C3BA86C69EA4B7376F31A9BCB4F74C1976089B2D9963DA2E5543E177769961764B3AA9B2FFCB6EF947B6887A226E8D7C93E00C5ED0C1834FF0D0C2E6DA6,FALSE,negated s value
+9,,DFF1D77F2A671C5F36183726DB2341BE58FEAE1DA2DECED843240F7B502BA659,,243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89,0000000000000000000000000000000000000000000000000000000000000000123DDA8328AF9C23A94C1FEECFD123BA4FB73476F0D594DCB65C6425BD186051,FALSE,sG - eP is infinite. Test fails in single verification if has_even_y(inf) is defined as true and x(inf) as 0
+10,,DFF1D77F2A671C5F36183726DB2341BE58FEAE1DA2DECED843240F7B502BA659,,243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89,00000000000000000000000000000000000000000000000000000000000000017615FBAF5AE28864013C099742DEADB4DBA87F11AC6754F93780D5A1837CF197,FALSE,sG - eP is infinite. Test fails in single verification if has_even_y(inf) is defined as true and x(inf) as 1
+11,,DFF1D77F2A671C5F36183726DB2341BE58FEAE1DA2DECED843240F7B502BA659,,243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89,4A298DACAE57395A15D0795DDBFD1DCB564DA82B0F269BC70A74F8220429BA1D69E89B4C5564D00349106B8497785DD7D1D713A8AE82B32FA79D5F7FC407D39B,FALSE,sig[0:32] is not an X coordinate on the curve
+12,,DFF1D77F2A671C5F36183726DB2341BE58FEAE1DA2DECED843240F7B502BA659,,243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89,FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFC2F69E89B4C5564D00349106B8497785DD7D1D713A8AE82B32FA79D5F7FC407D39B,FALSE,sig[0:32] is equal to field size
+13,,DFF1D77F2A671C5F36183726DB2341BE58FEAE1DA2DECED843240F7B502BA659,,243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89,6CFF5C3BA86C69EA4B7376F31A9BCB4F74C1976089B2D9963DA2E5543E177769FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141,FALSE,sig[32:64] is equal to curve order
+14,,FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFC30,,243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89,6CFF5C3BA86C69EA4B7376F31A9BCB4F74C1976089B2D9963DA2E5543E17776969E89B4C5564D00349106B8497785DD7D1D713A8AE82B32FA79D5F7FC407D39B,FALSE,public key is not a valid X coordinate because it exceeds the field size
+15,0340034003400340034003400340034003400340034003400340034003400340,778CAA53B4393AC467774D09497A87224BF9FAB6F6E68B23086497324D6FD117,0000000000000000000000000000000000000000000000000000000000000000,,71535DB165ECD9FBBC046E5FFAEA61186BB6AD436732FCCC25291A55895464CF6069CE26BF03466228F19A3A62DB8A649F2D560FAC652827D1AF0574E427AB63,TRUE,message of size 0 (added 2022-12)
+16,0340034003400340034003400340034003400340034003400340034003400340,778CAA53B4393AC467774D09497A87224BF9FAB6F6E68B23086497324D6FD117,0000000000000000000000000000000000000000000000000000000000000000,11,08A20A0AFEF64124649232E0693C583AB1B9934AE63B4C3511F3AE1134C6A303EA3173BFEA6683BD101FA5AA5DBC1996FE7CACFC5A577D33EC14564CEC2BACBF,TRUE,message of size 1 (added 2022-12)
+17,0340034003400340034003400340034003400340034003400340034003400340,778CAA53B4393AC467774D09497A87224BF9FAB6F6E68B23086497324D6FD117,0000000000000000000000000000000000000000000000000000000000000000,0102030405060708090A0B0C0D0E0F1011,5130F39A4059B43BC7CAC09A19ECE52B5D8699D1A71E3C52DA9AFDB6B50AC370C4A482B77BF960F8681540E25B6771ECE1E5A37FD80E5A51897C5566A97EA5A5,TRUE,message of size 17 (added 2022-12)
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message of size 100 (added 2022-12)
diff --git a/bip-0340/test-vectors.py b/bip-0340/test-vectors.py new file mode 100644 index 0000000..317f2ec --- /dev/null +++ b/bip-0340/test-vectors.py @@ -0,0 +1,300 @@ +import sys +from reference import * + +def is_square(x): + return int(pow(x, (p - 1) // 2, p)) == 1 + +def has_square_y(P): + """Determine if P has a square Y coordinate. Used in an earlier draft of BIP340.""" + assert not is_infinite(P) + return is_square(P[1]) + +def vector0(): + seckey = bytes_from_int(3) + msg = bytes_from_int(0) + aux_rand = bytes_from_int(0) + sig = schnorr_sign(msg, seckey, aux_rand) + pubkey = pubkey_gen(seckey) + + # We should have at least one test vector where the seckey needs to be + # negated and one where it doesn't. In this one the seckey doesn't need to + # be negated. + x = int_from_bytes(seckey) + P = point_mul(G, x) + assert(y(P) % 2 == 0) + + # For historical reasons (pubkey tiebreaker was squareness and not evenness) + # we should have at least one test vector where the the point reconstructed + # from the public key has a square and one where it has a non-square Y + # coordinate. In this one Y is non-square. + pubkey_point = lift_x(pubkey) + assert(not has_square_y(pubkey_point)) + + # For historical reasons (R tiebreaker was squareness and not evenness) + # we should have at least one test vector where the the point reconstructed + # from the R.x coordinate has a square and one where it has a non-square Y + # coordinate. In this one Y is non-square. + R = lift_x(sig[0:32]) + assert(not has_square_y(R)) + + return (seckey, pubkey, aux_rand, msg, sig, "TRUE", None) + +def vector1(): + seckey = bytes_from_int(0xB7E151628AED2A6ABF7158809CF4F3C762E7160F38B4DA56A784D9045190CFEF) + msg = bytes_from_int(0x243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89) + aux_rand = bytes_from_int(1) + + sig = schnorr_sign(msg, seckey, aux_rand) + + # The point reconstructed from the R.x coordinate has a square Y coordinate. + R = lift_x(sig[0:32]) + assert(has_square_y(R)) + + return (seckey, pubkey_gen(seckey), aux_rand, msg, sig, "TRUE", None) + +def vector2(): + seckey = bytes_from_int(0xC90FDAA22168C234C4C6628B80DC1CD129024E088A67CC74020BBEA63B14E5C9) + msg = bytes_from_int(0x7E2D58D8B3BCDF1ABADEC7829054F90DDA9805AAB56C77333024B9D0A508B75C) + aux_rand = bytes_from_int(0xC87AA53824B4D7AE2EB035A2B5BBBCCC080E76CDC6D1692C4B0B62D798E6D906) + sig = schnorr_sign(msg, seckey, aux_rand) + + # The point reconstructed from the public key has a square Y coordinate. + pubkey = pubkey_gen(seckey) + pubkey_point = lift_x(pubkey) + assert(has_square_y(pubkey_point)) + + # This signature vector would not verify if the implementer checked the + # evenness of the X coordinate of R instead of the Y coordinate. + R = lift_x(sig[0:32]) + assert(R[0] % 2 == 1) + + return (seckey, pubkey, aux_rand, msg, sig, "TRUE", None) + +def vector3(): + seckey = bytes_from_int(0x0B432B2677937381AEF05BB02A66ECD012773062CF3FA2549E44F58ED2401710) + + # Need to negate this seckey before signing + x = int_from_bytes(seckey) + P = point_mul(G, x) + assert(y(P) % 2 != 0) + + msg = bytes_from_int(0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF) + aux_rand = bytes_from_int(0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF) + + sig = schnorr_sign(msg, seckey, aux_rand) + return (seckey, pubkey_gen(seckey), aux_rand, msg, sig, "TRUE", "test fails if msg is reduced modulo p or n") + +# Signs with a given nonce. This can be INSECURE and is only INTENDED FOR +# GENERATING TEST VECTORS. Results in an invalid signature if y(kG) is not +# even. +def insecure_schnorr_sign_fixed_nonce(msg, seckey0, k): + if len(msg) != 32: + raise ValueError('The message must be a 32-byte array.') + seckey0 = int_from_bytes(seckey0) + if not (1 <= seckey0 <= n - 1): + raise ValueError('The secret key must be an integer in the range 1..n-1.') + P = point_mul(G, seckey0) + seckey = seckey0 if has_even_y(P) else n - seckey0 + R = point_mul(G, k) + e = int_from_bytes(tagged_hash("BIP0340/challenge", bytes_from_point(R) + bytes_from_point(P) + msg)) % n + return bytes_from_point(R) + bytes_from_int((k + e * seckey) % n) + +# Creates a singature with a small x(R) by using k = -1/2 +def vector4(): + one_half = n - 0x7fffffffffffffffffffffffffffffff5d576e7357a4501ddfe92f46681b20a0 + seckey = bytes_from_int(0x763758E5CBEEDEE4F7D3FC86F531C36578933228998226672F13C4F0EBE855EB) + msg = bytes_from_int(0x4DF3C3F68FCC83B27E9D42C90431A72499F17875C81A599B566C9889B9696703) + sig = insecure_schnorr_sign_fixed_nonce(msg, seckey, one_half) + return (None, pubkey_gen(seckey), None, msg, sig, "TRUE", None) + +default_seckey = bytes_from_int(0xB7E151628AED2A6ABF7158809CF4F3C762E7160F38B4DA56A784D9045190CFEF) +default_msg = bytes_from_int(0x243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89) +default_aux_rand = bytes_from_int(0xC87AA53824B4D7AE2EB035A2B5BBBCCC080E76CDC6D1692C4B0B62D798E6D906) + +# Public key is not on the curve +def vector5(): + # This creates a dummy signature that doesn't have anything to do with the + # public key. + seckey = default_seckey + msg = default_msg + sig = schnorr_sign(msg, seckey, default_aux_rand) + + pubkey = bytes_from_int(0xEEFDEA4CDB677750A420FEE807EACF21EB9898AE79B9768766E4FAA04A2D4A34) + assert(lift_x(pubkey) is None) + + return (None, pubkey, None, msg, sig, "FALSE", "public key not on the curve") + +def vector6(): + seckey = default_seckey + msg = default_msg + k = 6 + sig = insecure_schnorr_sign_fixed_nonce(msg, seckey, k) + + # Y coordinate of R is not even + R = point_mul(G, k) + assert(not has_even_y(R)) + + return (None, pubkey_gen(seckey), None, msg, sig, "FALSE", "has_even_y(R) is false") + +def vector7(): + seckey = default_seckey + msg = int_from_bytes(default_msg) + neg_msg = bytes_from_int(n - msg) + sig = schnorr_sign(neg_msg, seckey, default_aux_rand) + return (None, pubkey_gen(seckey), None, bytes_from_int(msg), sig, "FALSE", "negated message") + +def vector8(): + seckey = default_seckey + msg = default_msg + sig = schnorr_sign(msg, seckey, default_aux_rand) + sig = sig[0:32] + bytes_from_int(n - int_from_bytes(sig[32:64])) + return (None, pubkey_gen(seckey), None, msg, sig, "FALSE", "negated s value") + +def bytes_from_point_inf0(P): + if P == None: + return bytes_from_int(0) + return bytes_from_int(P[0]) + +def vector9(): + seckey = default_seckey + msg = default_msg + + # Override bytes_from_point in schnorr_sign to allow creating a signature + # with k = 0. + k = 0 + bytes_from_point_tmp = bytes_from_point.__code__ + bytes_from_point.__code__ = bytes_from_point_inf0.__code__ + sig = insecure_schnorr_sign_fixed_nonce(msg, seckey, k) + bytes_from_point.__code__ = bytes_from_point_tmp + + return (None, pubkey_gen(seckey), None, msg, sig, "FALSE", "sG - eP is infinite. Test fails in single verification if has_even_y(inf) is defined as true and x(inf) as 0") + +def bytes_from_point_inf1(P): + if P == None: + return bytes_from_int(1) + return bytes_from_int(P[0]) + +def vector10(): + seckey = default_seckey + msg = default_msg + + # Override bytes_from_point in schnorr_sign to allow creating a signature + # with k = 0. + k = 0 + bytes_from_point_tmp = bytes_from_point.__code__ + bytes_from_point.__code__ = bytes_from_point_inf1.__code__ + sig = insecure_schnorr_sign_fixed_nonce(msg, seckey, k) + bytes_from_point.__code__ = bytes_from_point_tmp + + return (None, pubkey_gen(seckey), None, msg, sig, "FALSE", "sG - eP is infinite. Test fails in single verification if has_even_y(inf) is defined as true and x(inf) as 1") + +# It's cryptographically impossible to create a test vector that fails if run +# in an implementation which merely misses the check that sig[0:32] is an X +# coordinate on the curve. This test vector just increases test coverage. +def vector11(): + seckey = default_seckey + msg = default_msg + sig = schnorr_sign(msg, seckey, default_aux_rand) + + # Replace R's X coordinate with an X coordinate that's not on the curve + x_not_on_curve = bytes_from_int(0x4A298DACAE57395A15D0795DDBFD1DCB564DA82B0F269BC70A74F8220429BA1D) + assert(lift_x(x_not_on_curve) is None) + sig = x_not_on_curve + sig[32:64] + + return (None, pubkey_gen(seckey), None, msg, sig, "FALSE", "sig[0:32] is not an X coordinate on the curve") + +# It's cryptographically impossible to create a test vector that fails if run +# in an implementation which merely misses the check that sig[0:32] is smaller +# than the field size. This test vector just increases test coverage. +def vector12(): + seckey = default_seckey + msg = default_msg + sig = schnorr_sign(msg, seckey, default_aux_rand) + + # Replace R's X coordinate with an X coordinate that's equal to field size + sig = bytes_from_int(p) + sig[32:64] + + return (None, pubkey_gen(seckey), None, msg, sig, "FALSE", "sig[0:32] is equal to field size") + +# It's cryptographically impossible to create a test vector that fails if run +# in an implementation which merely misses the check that sig[32:64] is smaller +# than the curve order. This test vector just increases test coverage. +def vector13(): + seckey = default_seckey + msg = default_msg + sig = schnorr_sign(msg, seckey, default_aux_rand) + + # Replace s with a number that's equal to the curve order + sig = sig[0:32] + bytes_from_int(n) + + return (None, pubkey_gen(seckey), None, msg, sig, "FALSE", "sig[32:64] is equal to curve order") + +# Test out of range pubkey +# It's cryptographically impossible to create a test vector that fails if run +# in an implementation which accepts out of range pubkeys because we can't find +# a secret key for such a public key and therefore can not create a signature. +# This test vector just increases test coverage. +def vector14(): + # This creates a dummy signature that doesn't have anything to do with the + # public key. + seckey = default_seckey + msg = default_msg + sig = schnorr_sign(msg, seckey, default_aux_rand) + pubkey_int = p + 1 + pubkey = bytes_from_int(pubkey_int) + assert(lift_x(pubkey) is None) + # If an implementation would reduce a given public key modulo p then the + # pubkey would be valid + assert(lift_x(bytes_from_int(pubkey_int % p)) is not None) + + return (None, pubkey, None, msg, sig, "FALSE", "public key is not a valid X coordinate because it exceeds the field size") + +def varlen_vector(msg_int): + seckey = bytes_from_int(int(16 * "0340", 16)) + pubkey = pubkey_gen(seckey) + aux_rand = bytes_from_int(0) + msg = msg_int.to_bytes((msg_int.bit_length() + 7) // 8, "big") + sig = schnorr_sign(msg, seckey, aux_rand) + comment = "message of size %d (added 2022-12)" + return (seckey, pubkey, aux_rand, msg, sig, "TRUE", comment % len(msg)) + +vector15 = lambda : varlen_vector(0) +vector16 = lambda : varlen_vector(0x11) +vector17 = lambda : varlen_vector(0x0102030405060708090A0B0C0D0E0F1011) +vector18 = lambda : varlen_vector(int(100 * "99", 16)) + +vectors = [ + vector0(), + vector1(), + vector2(), + vector3(), + vector4(), + vector5(), + vector6(), + vector7(), + vector8(), + vector9(), + vector10(), + vector11(), + vector12(), + vector13(), + vector14(), + vector15(), + vector16(), + vector17(), + vector18(), + ] + +# Converts the byte strings of a test vector into hex strings +def bytes_to_hex(seckey, pubkey, aux_rand, msg, sig, result, comment): + return (seckey.hex().upper() if seckey is not None else None, pubkey.hex().upper(), aux_rand.hex().upper() if aux_rand is not None else None, msg.hex().upper(), sig.hex().upper(), result, comment) + +vectors = list(map(lambda vector: bytes_to_hex(vector[0], vector[1], vector[2], vector[3], vector[4], vector[5], vector[6]), vectors)) + +def print_csv(vectors): + writer = csv.writer(sys.stdout) + writer.writerow(("index", "secret key", "public key", "aux_rand", "message", "signature", "verification result", "comment")) + for (i,v) in enumerate(vectors): + writer.writerow((i,)+v) + +print_csv(vectors) |