"""

    Verifies a P-256 signature.

    Parameters

    ----------

    evm :

        The current EVM frame.

    """

    data = evm.message.data

    # GAS

    charge_gas(evm, GAS_P256VERIFY)

    if len(data) != 160:

        return

    # OPERATION

    message_hash_bytes = buffer_read(data, U256(0), U256(32))

    message_hash = Hash32(message_hash_bytes)

    r = U256.from_be_bytes(buffer_read(data, U256(32), U256(32)))

    s = U256.from_be_bytes(buffer_read(data, U256(64), U256(32)))

    public_key_x = U256.from_be_bytes(

        buffer_read(data, U256(96), U256(32))

    )  # qx

    public_key_y = U256.from_be_bytes(

        buffer_read(data, U256(128), U256(32))

    )  # qy

    # Signature component bounds:

    # Both r and s MUST satisfy 0 < r < n and 0 < s < n

    if r <= U256(0) or r >= SECP256R1N:

        return

    if s <= U256(0) or s >= SECP256R1N:

        return

    # Public key bounds:

    # Both qx and qy MUST satisfy 0 ≤ qx < p and 0 ≤ qy < p

    # U256 is unsigned, so we don't need to check for < 0

    if public_key_x >= SECP256R1P:

        return

    if public_key_y >= SECP256R1P:

        return

    # Point should not be at infinity (represented as (0, 0))

    if public_key_x == U256(0) and public_key_y == U256(0):

        return

    # Point validity: The point (qx, qy) MUST satisfy the curve equation

    # qy^2 ≡ qx^3 + a*qx + b (mod p)

    if not is_on_curve_secp256r1(public_key_x, public_key_y):

        return

    try:

        secp256r1_verify(r, s, public_key_x, public_key_y, message_hash)

    except InvalidSignatureError:

        return

    evm.output = left_pad_zero_bytes(b"\x01", 32)