def generate_mlsag_simple(message, pubs, in_sk, a, cout, kLRki, index):
"""
MLSAG for RctType.Simple
:param message: the full message to be signed (actually its hash)
:param pubs: vector of MoneroRctKey; this forms the ring; point values in encoded form; (dest, mask) = (P, C)
:param in_sk: CtKey; spending private key with input commitment mask (original); better_name: input_secret_key
:param a: mask from the pseudo output commitment; better name: pseudo_out_alpha
:param cout: pseudo output commitment; point, decoded; better name: pseudo_out_c
:param kLRki: used only in multisig, currently not implemented
:param index: specifies corresponding public key to the `in_sk` in the pubs array
:return: MgSig
"""
# Monero signs inputs separately, so `rows` always equals 2 (pubkey, commitment)
# and `dsRows` is always 1 (denotes where the pubkeys "end")
rows = 2
dsRows = 1
cols = len(pubs)
if cols == 0:
raise ValueError("Empty pubs")
sk = _key_vector(rows)
M = _key_matrix(rows, cols)
sk[0] = in_sk.dest
sk[1] = crypto.sc_sub(in_sk.mask, a)
for i in range(cols):
M[i][0] = crypto.decodepoint(pubs[i].dest)
M[i][1] = crypto.point_sub(crypto.decodepoint(pubs[i].commitment),
cout)
return generate_mlsag(message, M, sk, kLRki, index, dsRows)
def gen_clsag_sig(self, ring_size=11, index=None):
msg = random.bytes(32)
amnt = crypto.sc_init(random.uniform(0xFFFFFF) + 12)
priv = crypto.random_scalar()
msk = crypto.random_scalar()
alpha = crypto.random_scalar()
P = crypto.scalarmult_base(priv)
C = crypto.add_keys2(msk, amnt, crypto.xmr_H())
Cp = crypto.add_keys2(alpha, amnt, crypto.xmr_H())
ring = []
for i in range(ring_size - 1):
tk = TmpKey(
crypto.encodepoint(
crypto.scalarmult_base(crypto.random_scalar())),
crypto.encodepoint(
crypto.scalarmult_base(crypto.random_scalar())),
)
ring.append(tk)
index = index if index is not None else random.uniform(len(ring))
ring.insert(index, TmpKey(crypto.encodepoint(P),
crypto.encodepoint(C)))
ring2 = list(ring)
mg_buffer = []
self.assertTrue(
crypto.point_eq(crypto.scalarmult_base(priv),
crypto.decodepoint(ring[index].dest)))
self.assertTrue(
crypto.point_eq(
crypto.scalarmult_base(crypto.sc_sub(msk, alpha)),
crypto.point_sub(crypto.decodepoint(ring[index].commitment),
Cp),
))
mlsag.generate_clsag_simple(
msg,
ring,
CtKey(priv, msk),
alpha,
Cp,
index,
mg_buffer,
)
sD = crypto.decodepoint(mg_buffer[-1])
sc1 = crypto.decodeint(mg_buffer[-2])
scalars = [crypto.decodeint(x) for x in mg_buffer[1:-2]]
H = crypto.new_point()
sI = crypto.new_point()
crypto.hash_to_point_into(H, crypto.encodepoint(P))
crypto.scalarmult_into(sI, H, priv) # I = p*H
return msg, scalars, sc1, sI, sD, ring2, Cp
def ecdh_decode(masked, receiver_sk=None, derivation=None):
"""
Elliptic Curve Diffie-Helman: encodes and decodes the amount b and mask a
where C= aG + bH
:param masked:
:param receiver_sk:
:param derivation:
:return:
"""
from apps.monero.xmr.serialize_messages.tx_ecdh import EcdhTuple
rv = EcdhTuple()
if derivation is None:
derivation = crypto.scalarmult(masked.senderPk, receiver_sk)
sharedSec1 = crypto.hash_to_scalar(derivation)
sharedSec2 = crypto.hash_to_scalar(crypto.encodeint(sharedSec1))
rv.mask = crypto.sc_sub(masked.mask, sharedSec1)
rv.amount = crypto.sc_sub(masked.amount, sharedSec2)
return rv
def generate_mlsag_full(message, pubs, in_sk, out_sk_mask, out_pk_commitments,
kLRki, index, txn_fee_key):
cols = len(pubs)
if cols == 0:
raise ValueError("Empty pubs")
rows = len(pubs[0])
if rows == 0:
raise ValueError("Empty pub row")
for i in range(cols):
if len(pubs[i]) != rows:
raise ValueError("pub is not rectangular")
if len(in_sk) != rows:
raise ValueError("Bad inSk size")
if len(out_sk_mask) != len(out_pk_commitments):
raise ValueError("Bad outsk/putpk size")
sk = _key_vector(rows + 1)
M = _key_matrix(rows + 1, cols)
for i in range(rows + 1):
sk[i] = crypto.sc_0()
for i in range(cols):
M[i][rows] = crypto.identity()
for j in range(rows):
M[i][j] = crypto.decodepoint(pubs[i][j].dest)
M[i][rows] = crypto.point_add(
M[i][rows], crypto.decodepoint(pubs[i][j].commitment))
sk[rows] = crypto.sc_0()
for j in range(rows):
sk[j] = in_sk[j].dest
sk[rows] = crypto.sc_add(sk[rows],
in_sk[j].mask) # add masks in last row
for i in range(cols):
for j in range(len(out_pk_commitments)):
M[i][rows] = crypto.point_sub(
M[i][rows], crypto.decodepoint(
out_pk_commitments[j])) # subtract output Ci's in last row
# Subtract txn fee output in last row
M[i][rows] = crypto.point_sub(M[i][rows], txn_fee_key)
for j in range(len(out_pk_commitments)):
sk[rows] = crypto.sc_sub(
sk[rows], out_sk_mask[j]) # subtract output masks in last row
return generate_mlsag(message, M, sk, kLRki, index, rows)
def generate_mlsag_simple(
message: bytes,
pubs: list[MoneroRctKeyPublic],
in_sk: CtKey,
a: Sc25519,
cout: Ge25519,
index: int,
mg_buff: list[bytes],
) -> list[bytes]:
"""
MLSAG for RctType.Simple
:param message: the full message to be signed (actually its hash)
:param pubs: vector of MoneroRctKey; this forms the ring; point values in encoded form; (dest, mask) = (P, C)
:param in_sk: CtKey; spending private key with input commitment mask (original); better_name: input_secret_key
:param a: mask from the pseudo output commitment; better name: pseudo_out_alpha
:param cout: pseudo output commitment; point, decoded; better name: pseudo_out_c
:param index: specifies corresponding public key to the `in_sk` in the pubs array
:param mg_buff: buffer to store the signature to
"""
# Monero signs inputs separately, so `rows` always equals 2 (pubkey, commitment)
# and `dsRows` is always 1 (denotes where the pubkeys "end")
rows = 2
dsRows = 1
cols = len(pubs)
if cols == 0:
raise ValueError("Empty pubs")
sk = _key_vector(rows)
M = _key_matrix(rows, cols)
sk[0] = in_sk.dest
sk[1] = crypto.sc_sub(in_sk.mask, a)
tmp_pt = crypto.new_point()
for i in range(cols):
crypto.point_sub_into(
tmp_pt, crypto.decodepoint_into(tmp_pt, pubs[i].commitment), cout
)
M[i][0] = pubs[i].dest
M[i][1] = crypto.encodepoint(tmp_pt)
pubs[i] = None
del pubs
gc.collect()
return generate_mlsag(message, M, sk, index, dsRows, mg_buff)
def generate_clsag_simple(
message: bytes,
pubs: List[MoneroRctKeyPublic],
in_sk: CtKey,
a: Sc25519,
cout: Ge25519,
index: int,
mg_buff: List[bytes],
) -> List[bytes]:
"""
CLSAG for RctType.Simple
https://eprint.iacr.org/2019/654.pdf
Corresponds to proveRctCLSAGSimple in rctSigs.cpp
:param message: the full message to be signed (actually its hash)
:param pubs: vector of MoneroRctKey; this forms the ring; point values in encoded form; (dest, mask) = (P, C)
:param in_sk: CtKey; spending private key with input commitment mask (original); better_name: input_secret_key
:param a: mask from the pseudo output commitment; better name: pseudo_out_alpha
:param cout: pseudo output commitment; point, decoded; better name: pseudo_out_c
:param index: specifies corresponding public key to the `in_sk` in the pubs array
:param mg_buff: buffer to store the signature to
"""
cols = len(pubs)
if cols == 0:
raise ValueError("Empty pubs")
P = _key_vector(cols)
C_nonzero = _key_vector(cols)
p = in_sk.dest
z = crypto.sc_sub(in_sk.mask, a)
for i in range(cols):
P[i] = pubs[i].dest
C_nonzero[i] = pubs[i].commitment
pubs[i] = None
del pubs
gc.collect()
return _generate_clsag(message, P, p, C_nonzero, z, cout, index, mg_buff)
def check_ring_singature(prefix_hash, image, pubs, sig):
"""
Checks ring signature generated with generate_ring_signature
:param prefix_hash:
:param image:
:param pubs:
:param sig:
:return:
"""
from apps.monero.xmr.common import memcpy
image_unp = crypto.ge_frombytes_vartime(image)
image_pre = crypto.ge_dsm_precomp(image_unp)
buff_off = len(prefix_hash)
buff = bytearray(buff_off + 2 * 32 * len(pubs))
memcpy(buff, 0, prefix_hash, 0, buff_off)
mvbuff = memoryview(buff)
sum = crypto.sc_0()
for i in range(len(pubs)):
if crypto.sc_check(sig[i][0]) != 0 or crypto.sc_check(sig[i][1]) != 0:
return False
tmp3 = crypto.ge_frombytes_vartime(pubs[i])
tmp2 = crypto.ge_double_scalarmult_base_vartime(
sig[i][0], tmp3, sig[i][1])
crypto.encodepoint_into(tmp2, mvbuff[buff_off:buff_off + 32])
buff_off += 32
tmp3 = crypto.hash_to_ec(crypto.encodepoint(pubs[i]))
tmp2 = crypto.ge_double_scalarmult_precomp_vartime(
sig[i][1], tmp3, sig[i][0], image_pre)
crypto.encodepoint_into(tmp2, mvbuff[buff_off:buff_off + 32])
buff_off += 32
sum = crypto.sc_add(sum, sig[i][0])
h = crypto.hash_to_scalar(buff)
h = crypto.sc_sub(h, sum)
return crypto.sc_isnonzero(h) == 0
async def _compute_masks(state: State):
"""
Output masks computed in advance. Used with client_version=0 && HF9.
After HF10 (included) masks are deterministic, computed from the amount_key.
After all client update to v1 this code will be removed.
In order to preserve client_version=0 compatibility the masks have to be adjusted.
"""
from trezor.messages.MoneroTransactionRsigData import MoneroTransactionRsigData
from apps.monero.signing import offloading_keys
rsig_data = MoneroTransactionRsigData()
# If range proofs are being offloaded, we send the masks to the host, which uses them
# to create the range proof. If not, we do not send any and we use them in the following step.
if state.rsig_offload:
rsig_data.mask = []
# Deterministic masks, the last one is computed to balance the sums
for i in range(state.output_count):
if i + 1 == state.output_count:
cur_mask = crypto.sc_sub(state.sumpouts_alphas, state.sumout)
state.output_last_mask = cur_mask
else:
cur_mask = offloading_keys.det_comm_masks(state.key_enc, i)
crypto.sc_add_into(state.sumout, state.sumout, cur_mask)
if state.rsig_offload:
rsig_data.mask.append(crypto.encodeint(cur_mask))
if not crypto.sc_eq(state.sumpouts_alphas, state.sumout):
raise ValueError("Sum eq error")
state.sumout = crypto.sc_init(0)
return rsig_data
def generate_ring_signature(
prefix_hash: bytes,
image: Ge25519,
pubs: list[Ge25519],
sec: Sc25519,
sec_idx: int,
test: bool = False,
) -> Sig:
"""
Generates ring signature with key image.
void crypto_ops::generate_ring_signature()
"""
from trezor.utils import memcpy
if test:
t = crypto.scalarmult_base(sec)
if not crypto.point_eq(t, pubs[sec_idx]):
raise ValueError("Invalid sec key")
k_i = monero.generate_key_image(crypto.encodepoint(pubs[sec_idx]), sec)
if not crypto.point_eq(k_i, image):
raise ValueError("Key image invalid")
for k in pubs:
crypto.check_ed25519point(k)
buff_off = len(prefix_hash)
buff = bytearray(buff_off + 2 * 32 * len(pubs))
memcpy(buff, 0, prefix_hash, 0, buff_off)
mvbuff = memoryview(buff)
sum = crypto.sc_0()
k = crypto.sc_0()
sig = []
for _ in range(len(pubs)):
sig.append([crypto.sc_0(), crypto.sc_0()]) # c, r
for i in range(len(pubs)):
if i == sec_idx:
k = crypto.random_scalar()
tmp3 = crypto.scalarmult_base(k)
crypto.encodepoint_into(mvbuff[buff_off:buff_off + 32], tmp3)
buff_off += 32
tmp3 = crypto.hash_to_point(crypto.encodepoint(pubs[i]))
tmp2 = crypto.scalarmult(tmp3, k)
crypto.encodepoint_into(mvbuff[buff_off:buff_off + 32], tmp2)
buff_off += 32
else:
sig[i] = [crypto.random_scalar(), crypto.random_scalar()]
tmp3 = pubs[i]
tmp2 = crypto.ge25519_double_scalarmult_base_vartime(
sig[i][0], tmp3, sig[i][1])
crypto.encodepoint_into(mvbuff[buff_off:buff_off + 32], tmp2)
buff_off += 32
tmp3 = crypto.hash_to_point(crypto.encodepoint(tmp3))
tmp2 = crypto.ge25519_double_scalarmult_vartime2(
sig[i][1], tmp3, sig[i][0], image)
crypto.encodepoint_into(mvbuff[buff_off:buff_off + 32], tmp2)
buff_off += 32
sum = crypto.sc_add(sum, sig[i][0])
h = crypto.hash_to_scalar(buff)
sig[sec_idx][0] = crypto.sc_sub(h, sum)
sig[sec_idx][1] = crypto.sc_mulsub(sig[sec_idx][0], sec, k)
return sig
def prove_range_mem(amount, last_mask=None):
"""
Memory optimized range proof.
Gives C, and mask such that \sumCi = C
c.f. http:#eprint.iacr.org/2015/1098 section 5.1
Ci is a commitment to either 0 or 2^i, i=0,...,63
thus this proves that "amount" is in [0, 2^ATOMS]
mask is a such that C = aG + bH, and b = amount
:param amount:
:param last_mask: ai[ATOMS-1] will be computed as \sum_{i=0}^{ATOMS-2} a_i - last_mask
:param use_asnl: use ASNL, used before Borromean
:return: sumCi, mask, RangeSig.
sumCi is Pedersen commitment on the amount value. sumCi = aG + amount*H
mask is "a" from the Pedersent commitment above.
"""
res = bytearray(32 * (64 + 64 + 64 + 1))
mv = memoryview(res)
gc.collect()
def as0(mv, x, i):
crypto.encodeint_into(x, mv[32 * i:])
def as1(mv, x, i):
crypto.encodeint_into(x, mv[32 * 64 + 32 * i:])
def aci(mv, x, i):
crypto.encodepoint_into(x, mv[32 * 64 * 2 + 32 + 32 * i:])
n = 64
bb = d2b(amount, n) # gives binary form of bb in "digits" binary digits
ai = key_zero_vector(n)
a = crypto.sc_0()
C = crypto.identity()
alpha = key_zero_vector(n)
c_H = crypto.gen_H()
kck = crypto.get_keccak() # ee computation
# First pass, generates: ai, alpha, Ci, ee, s1
for ii in range(n):
ai[ii] = crypto.random_scalar()
if last_mask is not None and ii == 64 - 1:
ai[ii] = crypto.sc_sub(last_mask, a)
a = crypto.sc_add(
a, ai[ii]
) # creating the total mask since you have to pass this to receiver...
alpha[ii] = crypto.random_scalar()
L = crypto.scalarmult_base(alpha[ii])
if bb[ii] == 0:
Ctmp = crypto.scalarmult_base(ai[ii])
else:
Ctmp = crypto.point_add(crypto.scalarmult_base(ai[ii]), c_H)
C = crypto.point_add(C, Ctmp)
aci(mv, Ctmp, ii)
if bb[ii] == 0:
si = crypto.random_scalar()
c = crypto.hash_to_scalar(crypto.encodepoint(L))
L = crypto.add_keys2(si, c, crypto.point_sub(Ctmp, c_H))
kck.update(crypto.encodepoint(L))
as1(mv, si, ii)
else:
kck.update(crypto.encodepoint(L))
c_H = crypto.point_double(c_H)
# Compute ee, memory cleanup
ee = crypto.sc_reduce32(crypto.decodeint(kck.digest()))
crypto.encodeint_into(ee, mv[64 * 32 * 2:])
del kck
gc.collect()
# Second phase computes: s0, s1
c_H = crypto.gen_H()
for jj in range(n):
if not bb[jj]:
s0 = crypto.sc_mulsub(ai[jj], ee, alpha[jj])
else:
s0 = crypto.random_scalar()
Ctmp = crypto.decodepoint(
mv[32 * 64 * 2 + 32 + 32 * jj:32 * 64 * 2 + 32 + 32 * jj + 32])
LL = crypto.add_keys2(s0, ee, Ctmp)
cc = crypto.hash_to_scalar(crypto.encodepoint(LL))
si = crypto.sc_mulsub(ai[jj], cc, alpha[jj])
as1(mv, si, jj)
as0(mv, s0, jj)
c_H = crypto.point_double(c_H)
gc.collect()
return C, a, res
def generate_ring_signature(prefix_hash,
image,
pubs,
sec,
sec_idx,
test=False):
"""
Generates ring signature with key image.
void crypto_ops::generate_ring_signature()
:param prefix_hash:
:param image:
:param pubs:
:param sec:
:param sec_idx:
:param test:
:return:
"""
from apps.monero.xmr.common import memcpy
if test:
from apps.monero.xmr import monero
t = crypto.scalarmult_base(sec)
if not crypto.point_eq(t, pubs[sec_idx]):
raise ValueError("Invalid sec key")
k_i = monero.generate_key_image(crypto.encodepoint(pubs[sec_idx]), sec)
if not crypto.point_eq(k_i, image):
raise ValueError("Key image invalid")
for k in pubs:
crypto.ge_frombytes_vartime_check(k)
image_unp = crypto.ge_frombytes_vartime(image)
image_pre = crypto.ge_dsm_precomp(image_unp)
buff_off = len(prefix_hash)
buff = bytearray(buff_off + 2 * 32 * len(pubs))
memcpy(buff, 0, prefix_hash, 0, buff_off)
mvbuff = memoryview(buff)
sum = crypto.sc_0()
k = crypto.sc_0()
sig = []
for i in range(len(pubs)):
sig.append([crypto.sc_0(), crypto.sc_0()]) # c, r
for i in range(len(pubs)):
if i == sec_idx:
k = crypto.random_scalar()
tmp3 = crypto.scalarmult_base(k)
crypto.encodepoint_into(tmp3, mvbuff[buff_off:buff_off + 32])
buff_off += 32
tmp3 = crypto.hash_to_ec(crypto.encodepoint(pubs[i]))
tmp2 = crypto.scalarmult(tmp3, k)
crypto.encodepoint_into(tmp2, mvbuff[buff_off:buff_off + 32])
buff_off += 32
else:
sig[i] = [crypto.random_scalar(), crypto.random_scalar()]
tmp3 = crypto.ge_frombytes_vartime(pubs[i])
tmp2 = crypto.ge_double_scalarmult_base_vartime(
sig[i][0], tmp3, sig[i][1])
crypto.encodepoint_into(tmp2, mvbuff[buff_off:buff_off + 32])
buff_off += 32
tmp3 = crypto.hash_to_ec(crypto.encodepoint(tmp3))
tmp2 = crypto.ge_double_scalarmult_precomp_vartime(
sig[i][1], tmp3, sig[i][0], image_pre)
crypto.encodepoint_into(tmp2, mvbuff[buff_off:buff_off + 32])
buff_off += 32
sum = crypto.sc_add(sum, sig[i][0])
h = crypto.hash_to_scalar(buff)
sig[sec_idx][0] = crypto.sc_sub(h, sum)
sig[sec_idx][1] = crypto.sc_mulsub(sig[sec_idx][0], sec, k)
return sig
async def sign_input(
state: State,
src_entr: MoneroTransactionSourceEntry,
vini_bin: bytes,
vini_hmac: bytes,
pseudo_out: bytes,
pseudo_out_hmac: bytes,
pseudo_out_alpha_enc: bytes,
spend_enc: bytes,
orig_idx: int,
) -> MoneroTransactionSignInputAck:
"""
:param state: transaction state
:param src_entr: Source entry
:param vini_bin: tx.vin[i] for the transaction. Contains key image, offsets, amount (usually zero)
:param vini_hmac: HMAC for the tx.vin[i] as returned from Trezor
:param pseudo_out: Pedersen commitment for the current input, uses pseudo_out_alpha
as a mask. Only applicable for RCTTypeSimple.
:param pseudo_out_hmac: HMAC for pseudo_out
:param pseudo_out_alpha_enc: alpha mask used in pseudo_out, only applicable for RCTTypeSimple. Encrypted.
:param spend_enc: one time address spending private key. Encrypted.
:param orig_idx: original index of the src_entr before sorting (HMAC check)
:return: Generated signature MGs[i]
"""
await confirms.transaction_step(state, state.STEP_SIGN,
state.current_input_index + 1)
state.current_input_index += 1
if state.last_step not in (state.STEP_ALL_OUT, state.STEP_SIGN):
raise ValueError("Invalid state transition")
if state.current_input_index >= state.input_count:
raise ValueError("Invalid inputs count")
if pseudo_out is None:
raise ValueError("SimpleRCT requires pseudo_out but none provided")
if pseudo_out_alpha_enc is None:
raise ValueError(
"SimpleRCT requires pseudo_out's mask but none provided")
input_position = (state.source_permutation[state.current_input_index]
if state.client_version <= 1 else orig_idx)
mods = utils.unimport_begin()
# Check input's HMAC
from apps.monero.signing import offloading_keys
vini_hmac_comp = await offloading_keys.gen_hmac_vini(
state.key_hmac, src_entr, vini_bin, input_position)
if not crypto.ct_equals(vini_hmac_comp, vini_hmac):
raise ValueError("HMAC is not correct")
# Key image sorting check - permutation correctness
cur_ki = offloading_keys.get_ki_from_vini(vini_bin)
if state.current_input_index > 0 and state.last_ki <= cur_ki:
raise ValueError("Key image order invalid")
state.last_ki = cur_ki if state.current_input_index < state.input_count else None
del (cur_ki, vini_bin, vini_hmac, vini_hmac_comp)
gc.collect()
state.mem_trace(1, True)
from apps.monero.xmr.crypto import chacha_poly
pseudo_out_alpha = crypto.decodeint(
chacha_poly.decrypt_pack(
offloading_keys.enc_key_txin_alpha(state.key_enc, input_position),
bytes(pseudo_out_alpha_enc),
))
# Last pseudo_out is recomputed so mask sums hold
if input_position + 1 == state.input_count:
# Recompute the lash alpha so the sum holds
state.mem_trace("Correcting alpha")
alpha_diff = crypto.sc_sub(state.sumout, state.sumpouts_alphas)
crypto.sc_add_into(pseudo_out_alpha, pseudo_out_alpha, alpha_diff)
pseudo_out_c = crypto.gen_commitment(pseudo_out_alpha,
state.input_last_amount)
else:
if input_position + 1 == state.input_count:
utils.ensure(crypto.sc_eq(state.sumpouts_alphas, state.sumout),
"Sum eq error")
# both pseudo_out and its mask were offloaded so we need to
# validate pseudo_out's HMAC and decrypt the alpha
pseudo_out_hmac_comp = crypto.compute_hmac(
offloading_keys.hmac_key_txin_comm(state.key_hmac, input_position),
pseudo_out,
)
if not crypto.ct_equals(pseudo_out_hmac_comp, pseudo_out_hmac):
raise ValueError("HMAC is not correct")
pseudo_out_c = crypto.decodepoint(pseudo_out)
state.mem_trace(2, True)
# Spending secret
spend_key = crypto.decodeint(
chacha_poly.decrypt_pack(
offloading_keys.enc_key_spend(state.key_enc, input_position),
bytes(spend_enc),
))
del (
offloading_keys,
chacha_poly,
pseudo_out,
pseudo_out_hmac,
pseudo_out_alpha_enc,
spend_enc,
)
utils.unimport_end(mods)
state.mem_trace(3, True)
# Basic setup, sanity check
from apps.monero.xmr.serialize_messages.tx_ct_key import CtKey
index = src_entr.real_output
input_secret_key = CtKey(spend_key, crypto.decodeint(src_entr.mask))
# Private key correctness test
utils.ensure(
crypto.point_eq(
crypto.decodepoint(
src_entr.outputs[src_entr.real_output].key.dest),
crypto.scalarmult_base(input_secret_key.dest),
),
"Real source entry's destination does not equal spend key's",
)
utils.ensure(
crypto.point_eq(
crypto.decodepoint(
src_entr.outputs[src_entr.real_output].key.commitment),
crypto.gen_commitment(input_secret_key.mask, src_entr.amount),
),
"Real source entry's mask does not equal spend key's",
)
state.mem_trace(4, True)
from apps.monero.xmr import mlsag
mg_buffer = []
ring_pubkeys = [x.key for x in src_entr.outputs if x]
utils.ensure(len(ring_pubkeys) == len(src_entr.outputs), "Invalid ring")
del src_entr
state.mem_trace(5, True)
if state.hard_fork and state.hard_fork >= 13:
state.mem_trace("CLSAG")
mlsag.generate_clsag_simple(
state.full_message,
ring_pubkeys,
input_secret_key,
pseudo_out_alpha,
pseudo_out_c,
index,
mg_buffer,
)
else:
mlsag.generate_mlsag_simple(
state.full_message,
ring_pubkeys,
input_secret_key,
pseudo_out_alpha,
pseudo_out_c,
index,
mg_buffer,
)
del (CtKey, input_secret_key, pseudo_out_alpha, mlsag, ring_pubkeys)
state.mem_trace(6, True)
from trezor.messages.MoneroTransactionSignInputAck import (
MoneroTransactionSignInputAck, )
# Encrypt signature, reveal once protocol finishes OK
if state.client_version >= 3:
utils.unimport_end(mods)
state.mem_trace(7, True)
mg_buffer = _protect_signature(state, mg_buffer)
state.mem_trace(8, True)
state.last_step = state.STEP_SIGN
return MoneroTransactionSignInputAck(
signature=mg_buffer, pseudo_out=crypto.encodepoint(pseudo_out_c))
async def sign_input(
state: State,
src_entr: MoneroTransactionSourceEntry,
vini_bin: bytes,
vini_hmac: bytes,
pseudo_out: bytes,
pseudo_out_hmac: bytes,
pseudo_out_alpha_enc: bytes,
spend_enc: bytes,
):
"""
:param state: transaction state
:param src_entr: Source entry
:param vini_bin: tx.vin[i] for the transaction. Contains key image, offsets, amount (usually zero)
:param vini_hmac: HMAC for the tx.vin[i] as returned from Trezor
:param pseudo_out: Pedersen commitment for the current input, uses pseudo_out_alpha
as a mask. Only applicable for RCTTypeSimple.
:param pseudo_out_hmac: HMAC for pseudo_out
:param pseudo_out_alpha_enc: alpha mask used in pseudo_out, only applicable for RCTTypeSimple. Encrypted.
:param spend_enc: one time address spending private key. Encrypted.
:return: Generated signature MGs[i]
"""
await confirms.transaction_step(state, state.STEP_SIGN,
state.current_input_index + 1)
state.current_input_index += 1
if state.current_input_index >= state.input_count:
raise ValueError("Invalid inputs count")
if pseudo_out is None:
raise ValueError("SimpleRCT requires pseudo_out but none provided")
if pseudo_out_alpha_enc is None:
raise ValueError(
"SimpleRCT requires pseudo_out's mask but none provided")
input_position = state.source_permutation[state.current_input_index]
mods = utils.unimport_begin()
# Check input's HMAC
from apps.monero.signing import offloading_keys
vini_hmac_comp = await offloading_keys.gen_hmac_vini(
state.key_hmac, src_entr, vini_bin, input_position)
if not crypto.ct_equals(vini_hmac_comp, vini_hmac):
raise ValueError("HMAC is not correct")
gc.collect()
state.mem_trace(1, True)
from apps.monero.xmr.crypto import chacha_poly
pseudo_out_alpha = crypto.decodeint(
chacha_poly.decrypt_pack(
offloading_keys.enc_key_txin_alpha(state.key_enc, input_position),
bytes(pseudo_out_alpha_enc),
))
# Last pseud_out is recomputed so mask sums hold
if state.is_det_mask() and input_position + 1 == state.input_count:
# Recompute the lash alpha so the sum holds
state.mem_trace("Correcting alpha")
alpha_diff = crypto.sc_sub(state.sumout, state.sumpouts_alphas)
crypto.sc_add_into(pseudo_out_alpha, pseudo_out_alpha, alpha_diff)
pseudo_out_c = crypto.gen_commitment(pseudo_out_alpha,
state.input_last_amount)
else:
if input_position + 1 == state.input_count:
utils.ensure(crypto.sc_eq(state.sumpouts_alphas, state.sumout),
"Sum eq error")
# both pseudo_out and its mask were offloaded so we need to
# validate pseudo_out's HMAC and decrypt the alpha
pseudo_out_hmac_comp = crypto.compute_hmac(
offloading_keys.hmac_key_txin_comm(state.key_hmac, input_position),
pseudo_out,
)
if not crypto.ct_equals(pseudo_out_hmac_comp, pseudo_out_hmac):
raise ValueError("HMAC is not correct")
pseudo_out_c = crypto.decodepoint(pseudo_out)
state.mem_trace(2, True)
# Spending secret
spend_key = crypto.decodeint(
chacha_poly.decrypt_pack(
offloading_keys.enc_key_spend(state.key_enc, input_position),
bytes(spend_enc),
))
del (
offloading_keys,
chacha_poly,
pseudo_out,
pseudo_out_hmac,
pseudo_out_alpha_enc,
spend_enc,
)
utils.unimport_end(mods)
state.mem_trace(3, True)
from apps.monero.xmr.serialize_messages.ct_keys import CtKey
# Basic setup, sanity check
index = src_entr.real_output
input_secret_key = CtKey(dest=spend_key,
mask=crypto.decodeint(src_entr.mask))
kLRki = None # for multisig: src_entr.multisig_kLRki
# Private key correctness test
utils.ensure(
crypto.point_eq(
crypto.decodepoint(
src_entr.outputs[src_entr.real_output].key.dest),
crypto.scalarmult_base(input_secret_key.dest),
),
"Real source entry's destination does not equal spend key's",
)
utils.ensure(
crypto.point_eq(
crypto.decodepoint(
src_entr.outputs[src_entr.real_output].key.commitment),
crypto.gen_commitment(input_secret_key.mask, src_entr.amount),
),
"Real source entry's mask does not equal spend key's",
)
state.mem_trace(4, True)
from apps.monero.xmr import mlsag
mg_buffer = []
ring_pubkeys = [x.key for x in src_entr.outputs]
del src_entr
mlsag.generate_mlsag_simple(
state.full_message,
ring_pubkeys,
input_secret_key,
pseudo_out_alpha,
pseudo_out_c,
kLRki,
index,
mg_buffer,
)
del (input_secret_key, pseudo_out_alpha, mlsag, ring_pubkeys)
state.mem_trace(5, True)
from trezor.messages.MoneroTransactionSignInputAck import (
MoneroTransactionSignInputAck, )
return MoneroTransactionSignInputAck(
signature=mg_buffer, pseudo_out=crypto.encodepoint(pseudo_out_c))
def verify_clsag(self, msg, ss, sc1, sI, sD, pubs, C_offset):
n = len(pubs)
c = crypto.new_scalar()
D_8 = crypto.new_point()
tmp_bf = bytearray(32)
C_offset_bf = crypto.encodepoint(C_offset)
crypto.sc_copy(c, sc1)
crypto.point_mul8_into(D_8, sD)
hsh_P = crypto.get_keccak() # domain, I, D, P, C, C_offset
hsh_C = crypto.get_keccak() # domain, I, D, P, C, C_offset
hsh_P.update(mlsag._HASH_KEY_CLSAG_AGG_0)
hsh_C.update(mlsag._HASH_KEY_CLSAG_AGG_1)
def hsh_PC(x):
hsh_P.update(x)
hsh_C.update(x)
for x in pubs:
hsh_PC(x.dest)
for x in pubs:
hsh_PC(x.commitment)
hsh_PC(crypto.encodepoint_into(tmp_bf, sI))
hsh_PC(crypto.encodepoint_into(tmp_bf, sD))
hsh_PC(C_offset_bf)
mu_P = crypto.decodeint(hsh_P.digest())
mu_C = crypto.decodeint(hsh_C.digest())
c_to_hash = crypto.get_keccak(
) # domain, P, C, C_offset, message, L, R
c_to_hash.update(mlsag._HASH_KEY_CLSAG_ROUND)
for i in range(len(pubs)):
c_to_hash.update(pubs[i].dest)
for i in range(len(pubs)):
c_to_hash.update(pubs[i].commitment)
c_to_hash.update(C_offset_bf)
c_to_hash.update(msg)
c_p = crypto.new_scalar()
c_c = crypto.new_scalar()
L = crypto.new_point()
R = crypto.new_point()
tmp_pt = crypto.new_point()
i = 0
while i < n:
crypto.sc_mul_into(c_p, mu_P, c)
crypto.sc_mul_into(c_c, mu_C, c)
C_P = crypto.point_sub(
crypto.decodepoint_into(tmp_pt, pubs[i].commitment), C_offset)
crypto.add_keys2_into(
L, ss[i], c_p, crypto.decodepoint_into(tmp_pt, pubs[i].dest))
crypto.point_add_into(L, L,
crypto.scalarmult_into(tmp_pt, C_P, c_c))
HP = crypto.hash_to_point(pubs[i].dest)
crypto.add_keys3_into(R, ss[i], HP, c_p, sI)
crypto.point_add_into(R, R,
crypto.scalarmult_into(tmp_pt, D_8, c_c))
chasher = c_to_hash.copy()
chasher.update(crypto.encodepoint_into(tmp_bf, L))
chasher.update(crypto.encodepoint_into(tmp_bf, R))
crypto.decodeint_into(c, chasher.digest())
i += 1
res = crypto.sc_sub(c, sc1)
if not crypto.sc_eq(res, crypto.sc_0()):
raise ValueError("Signature error")
