socks.py 文件源码

def _write_SOCKS5_address(self, addr, file):
        """
        Return the host and port packed for the SOCKS5 protocol,
        and the resolved address as a tuple object.
        """
        host, port = addr
        proxy_type, _, _, rdns, username, password = self.proxy
        family_to_byte = {socket.AF_INET: b"\x01", socket.AF_INET6: b"\x04"}

        # If the given destination address is an IP address, we'll
        # use the IP address request even if remote resolving was specified.
        # Detect whether the address is IPv4/6 directly.
        for family in (socket.AF_INET, socket.AF_INET6):
            try:
                addr_bytes = socket.inet_pton(family, host)
                file.write(family_to_byte[family] + addr_bytes)
                host = socket.inet_ntop(family, addr_bytes)
                file.write(struct.pack(">H", port))
                return host, port
            except socket.error:
                continue

        # Well it's not an IP number, so it's probably a DNS name.
        if rdns:
            # Resolve remotely
            host_bytes = host.encode('idna')
            file.write(b"\x03" + chr(len(host_bytes)).encode() + host_bytes)
        else:
            # Resolve locally
            addresses = socket.getaddrinfo(host, port, socket.AF_UNSPEC, socket.SOCK_STREAM, socket.IPPROTO_TCP, socket.AI_ADDRCONFIG)
            # We can't really work out what IP is reachable, so just pick the
            # first.
            target_addr = addresses[0]
            family = target_addr[0]
            host = target_addr[4][0]

            addr_bytes = socket.inet_pton(family, host)
            file.write(family_to_byte[family] + addr_bytes)
            host = socket.inet_ntop(family, addr_bytes)
        file.write(struct.pack(">H", port))
        return host, port