ed25519_oop.py 文件源码

def from_ascii(s_ascii, prefix="", encoding="base64"):
    """This is the opposite of to_ascii. It will throw BadPrefixError if
    the prefix is not found.
    """
    if isinstance(s_ascii, bytes):
        s_ascii = s_ascii.decode('ascii')
    if isinstance(prefix, bytes):
        prefix = prefix.decode('ascii')
    s_ascii = remove_prefix(s_ascii.strip(), prefix)
    if encoding == "base64":
        s_ascii += "="*((4 - len(s_ascii)%4)%4)
        s_bytes = base64.b64decode(s_ascii)
    elif encoding == "base32":
        s_ascii += "="*((8 - len(s_ascii)%8)%8)
        s_bytes = base64.b32decode(s_ascii.upper())
    elif encoding in ("base16", "hex"):
        s_bytes = base64.b16decode(s_ascii.upper())
    else:
        raise NotImplementedError
    return s_bytes