Module org.jnetpcap
Package org.jnetpcap

Class PcapIf

java.lang.Object
org.jnetpcap.PcapIf
public class PcapIf extends Object
Native Type pcap_if_t has the following members.
next
if not NULL, a pointer to the next element in the list; NULL for the last element of the list
name
a pointer to a string giving a name for the device to pass to pcap_open_live()
description
if not NULL, a pointer to a string giving a human-readable description of the device
addresses
a pointer to the first element of a list of network addresses for the device, or NULL if the device has no addresses
flags
device flags:
PCAP_IF_LOOPBACK
set if the device is a loopback interface
PCAP_IF_UP
set if the device is up
PCAP_IF_RUNNING
set if the device is running
PCAP_IF_WIRELESS
set if the device is a wireless interface; this includes IrDA as well as radio-based networks such as IEEE 802.15.4 and IEEE 802.11, so it doesn't just mean Wi-Fi
PCAP_IF_CONNECTION_STATUS
a bitmask for an indication of whether the adapter is connected or not; for wireless interfaces, "connected" means "associated with a network"
PCAP_IF_CONNECTION_STATUS_UNKNOWN
it's unknown whether the adapter is connected or not
PCAP_IF_CONNECTION_STATUS_CONNECTED
the adapter is connected
PCAP_IF_CONNECTION_STATUS_DISCONNECTED
the adapter is disconnected
PCAP_IF_CONNECTION_STATUS_NOT_APPLICABLE
the notion of "connected" and "disconnected" don't apply to this interface; for example, it doesn't apply to a loopback device

Each element of the list of addresses is of type pcap_addr_t, and has the following members:

next
if not NULL, a pointer to the next element in the list; NULL for the last element of the list
addr
a pointer to a struct sockaddr containing an address
netmask
if not NULL, a pointer to a struct sockaddr that contains the netmask corresponding to the address pointed to by addr
broadaddr
if not NULL, a pointer to a struct sockaddr that contains the broadcast address corresponding to the address pointed to by addr; may be null if the device doesn't support broadcasts
dstaddr
if not NULL, a pointer to a struct sockaddr that contains the destination address corresponding to the address pointed to by addr; may be null if the device isn't a point-to-point interface

Note that the addresses in the list of addresses might be IPv4 addresses, IPv6 addresses, or some other type of addresses, so you must check the sa_family member of the struct sockaddr before interpreting the contents of the address; do not assume that the addresses are all IPv4 addresses, or even all IPv4 or IPv6 addresses. IPv4 addresses have the value AF_INET, IPv6 addresses have the value AF_INET6 (which older operating systems that don't support IPv6 might not define), and other addresses have other values. Whether other addresses are returned, and what types they might have is platform-dependent. For IPv4 addresses, the struct sockaddr pointer can be interpreted as if it pointed to a struct sockaddr_in; for IPv6 addresses, it can be interpreted as if it pointed to a struct sockaddr_in6.

Author:
Sly Technologies, repos@slytechs.com since libpcap 0.7

  • Field Details

    • SYSTEM_PROPERTY_PCAPIF_SOCKADDR_BSD_STYLE

      public static final String SYSTEM_PROPERTY_PCAPIF_SOCKADDR_BSD_STYLE
      System property if set to true, pcap uses BSD style sockaddr structure which has the addr_len field. Otherwise the default heuristic are used to determine the sock address structure format.
      See Also:

    • PCAP_IF_LOOPBACK

      public static final int PCAP_IF_LOOPBACK
      interface is loopback.
      See Also:

    • PCAP_IF_UP

      public static final int PCAP_IF_UP
      interface is up.
      See Also:

    • PCAP_IF_RUNNING

      public static final int PCAP_IF_RUNNING
      interface is running.
      See Also:

  • Method Details

    • addresses

      public List<PcapIf.PcapAddr<?>> addresses()
      Gets a list of all the addresses (PcapAddr) associated with this pcap interface.
      Returns:
      the list of addresses

    • findAddressOfFamily

      public Optional<PcapIf.PcapAddr<? extends SockAddr>> findAddressOfFamily(SockAddrFamily family)
      Search for a PCAP address of a specific socket address family type.
      Parameters:
      family - the socket address family type
      Returns:
      the optional PCAP address if found

    • findAddressOfType

      public <T extends SockAddr> Optional<PcapIf.PcapAddr<T>> findAddressOfType(Class<T> faimlyClassType)
      Finds the first address in the list of PcapAddr addresses, which is of AF (Address Family) type represented but the supplied family subclass type.
      Type Parameters:
      T - the generic AF subclass type
      Parameters:
      faimlyClassType - the actual AF subclass type
      Returns:
      an optional if address represented by the family subclass if found

    • description

      public Optional<String> description()
      Optional textual description of the interface.
      Returns:
      the interface description if available

    • flags

      public int flags()
      Interface flags (e.g., PCAP_IF_LOOPBACK for loopback interfaces).
      Returns:
      the interface bitmask of flags

    • flagsAsEnumSet

      public Set<PcapIfFlag> flagsAsEnumSet()
      Interface flags (e.g., PCAP_IF_LOOPBACK for loopback interfaces), as an enum set.
      Returns:
      the set containing enum flag constants for each flag bit

    • hardwareAddress

      public Optional<byte[]> hardwareAddress()
      Returns the hardware address (usually MAC) of the interface if it has one and if it can be accessed given the current privileges.
      Returns:
      an optional byte array containing the address

    • name

      public String name()
      Name of the interface (e.g., "eth0") .
      Returns:
      the string

    • toString

      public String toString()
      String representation of the structure field values.
      Overrides:
      toString in class Object
      Returns:
      the string
      See Also: