2
Network introspection utilities using ioctl and the /proc filesystem.
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__all__ = ["get_active_device_info", "get_network_traffic"]
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# from header /usr/include/bits/ioctls.h
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SIOCGIFNETMASK = 0x891b
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SIOCGIFBRDADDR = 0x8919
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SIOCGIFHWADDR = 0x8927
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# struct definition from header /usr/include/net/if.h
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# the struct size varies according to the platform arch size
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# a minimal c program was used to determine the size of the
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# struct, standard headers removed for brevity.
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printf("Size of struct %lu\n", sizeof(struct ifreq));
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IF_STRUCT_SIZE_32 = 32
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IF_STRUCT_SIZE_64 = 40
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"""Returns C{True} if the platform is 64-bit, otherwise C{False}."""
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return struct.calcsize("l") == 8
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# initialize the struct size as per the machine's archictecture
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IF_STRUCT_SIZE = is_64() and IF_STRUCT_SIZE_64 or IF_STRUCT_SIZE_32
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def get_active_interfaces(sock):
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"""Generator yields active network interface names.
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@param sock: a socket instance.
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# Setup an an array to hold our response, and initialized to null strings.
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interfaces = array.array("B", "\0" * max_interfaces * IF_STRUCT_SIZE)
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buffer_size = interfaces.buffer_info()[0]
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packed_bytes = struct.pack(
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"iL", max_interfaces * IF_STRUCT_SIZE, buffer_size)
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byte_length = struct.unpack(
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"iL", fcntl.ioctl(sock.fileno(), SIOCGIFCONF, packed_bytes))[0]
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result = interfaces.tostring()
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# Generator over the interface names
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for index in range(0, byte_length, IF_STRUCT_SIZE):
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ifreq_struct = result[index:index+IF_STRUCT_SIZE]
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interface_name = ifreq_struct[:ifreq_struct.index("\0")]
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if interface_name not in already_found:
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already_found.add(interface_name)
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def get_broadcast_address(sock, interface):
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"""Return the broadcast address associated to an interface.
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@param sock: a socket instance.
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@param interface: The name of the interface.
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return socket.inet_ntoa(fcntl.ioctl(
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struct.pack("256s", interface[:15]))[20:24])
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def get_netmask(sock, interface):
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"""Return the network mask associated to an interface.
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@param sock: a socket instance.
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@param interface: The name of the interface.
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return socket.inet_ntoa(fcntl.ioctl(
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struct.pack("256s", interface[:15]))[20:24])
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def get_ip_address(sock, interface):
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"""Return the IP address associated to the interface.
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@param sock: a socket instance.
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@param interface: The name of the interface.
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return socket.inet_ntoa(fcntl.ioctl(
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struct.pack("256s", interface[:15]))[20:24])
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def get_mac_address(sock, interface):
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Return the hardware MAC address for an interface in human friendly form,
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ie. six colon separated groups of two hexadecimal digits.
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@param sock: a socket instance.
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@param interface: The name of the interface.
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mac_address = fcntl.ioctl(
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sock.fileno(), SIOCGIFHWADDR, struct.pack("256s", interface[:15]))
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return "".join(["%02x:" % ord(char) for char in mac_address[18:24]])[:-1]
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def get_flags(sock, interface):
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"""Return the integer value of the interface flags for the given interface.
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@param sock: a socket instance.
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@param interface: The name of the interface.
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@see /usr/include/linux/if.h for the meaning of the flags.
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sock.fileno(), SIOCGIFFLAGS, struct.pack("256s", interface[:15]))
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return struct.unpack("H", data[16:18])[0]
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def get_active_device_info():
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Returns a dictionary containing information on each active network
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interface present on a machine.
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sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM, socket.IPPROTO_IP)
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for interface in get_active_interfaces(sock):
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interface_info = {"interface": interface}
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interface_info["ip_address"] = get_ip_address(sock, interface)
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interface_info["mac_address"] = get_mac_address(sock, interface)
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interface_info["broadcast_address"] = get_broadcast_address(sock,
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interface_info["netmask"] = get_netmask(sock, interface)
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interface_info["flags"] = get_flags(sock, interface)
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results.append(interface_info)
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def get_network_traffic(source_file="/proc/net/dev"):
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Retrieves an array of information regarding the network activity per
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netdev = open(source_file, "r")
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lines = netdev.readlines()
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# Parse out the column headers as keys.
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_, receive_columns, transmit_columns = lines[1].split("|")
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columns = ["recv_%s" % column for column in receive_columns.split()]
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columns.extend(["send_%s" % column for column in transmit_columns.split()])
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# Parse out the network devices.
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for line in lines[2:]:
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device, data = line.split(":")
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device = device.strip()
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devices[device] = dict(zip(columns, map(long, data.split())))
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if __name__ == "__main__":
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pprint.pprint(get_active_device_info())
added
removed
landscape/lib/network.py
