NAME

if_tcp, if - general properties of Internet Protocol network interfaces

DESCRIPTION

A network interface is a device for sending and receiving packets on a network. It is usually a hardware device, although it can be implemented in software. Network interfaces used by the Internet Protocol (IPv4 or IPv6) must be STREAMS devices conforming to the Data Link Provider Interface (DLPI). See dlpi(4P).

APPLICATION PROGRAMMING INTERFACE

An interface becomes available to IP when it is opened and the IP module is pushed onto the stream with the I_PUSH ioctl(2) command. (See streamio(4I)). The SIOCSLIFNAME ioctl(2) is issued to specify the name of the interface and to indicate whether it is IPv4 or IPv6. This may be initiated by the kernel at boot time or by a user program after the system is running. Each interface must be assigned an IP address with the SIOCSLIFADDR ioctl() before it can be used. On interfaces where the network-to-link layer address mapping is static, only the network number is taken from the ioctl() request; the remainder is found in a hardware specific manner. On interfaces which provide dynamic network-to-link layer address mapping facilities (for example, Ethernets using arp(4P)), the entire address specified in the ioctl() is used. A routing table entry for destinations on the network of the interface is installed automatically when an interface's address is set.

You cannot create IPMP IP interfaces using the procedure described above. Instead, use ifconfig(8).

IOCTLS

The following ioctl() calls may be used to manipulate IP network interfaces. Unless specified otherwise, the request takes an lifreq structure as its parameter. This structure has the form:

struct lifreq {
#define LIFNAMSIZ	32


   char    lifr_name[LIFNAMSIZ];       /* if name, e.g. "le1" */


   union {


      int    lifru_addrlen;            /* for subnet/token etc */


      uint_t lifru_ppa;                /* SIOCSLIFNAME */


   } lifr_lifru1;


   union {


      struct sockaddr_storage lifru_addr;


      struct sockaddr_storage lifru_dstaddr;


      struct sockaddr_storage lifru_broadaddr;


      struct sockaddr_storage lifru_token;    /* With lifr_addrlen */


      struct sockaddr_storage lifru_subnet;   /* With lifr_addrlen */


      int                     lifru_index;    /* interface index */


      uint64_t                lifru_flags;    /* SIOC?LIFFLAGS */


      int                     lifru_metric;


      uint_t                  lifru_mtu;


      int                     lif_muxid[2];   /* mux id's for arp & ip */


      struct lif_nd_req       lifru_nd_req;   /* SIOCLIF*ND */


      struct lif_ifinfo_req   lifru_ifinfo_req;


      zoneid_t                lifru_zone;     /* SIOC[GS]LIFZONE */


   } lifr_lifru;
#define lifr_addrlen   lifr_lifru1.lifru_addrlen
#define lifr_ppa       lifr_lifru1.lifru_ppa       /* Driver's ppa */
#define lifr_addr      lifr_lifru.lifru_addr       /* address */
#define lifr_dstaddr   lifr_lifru.lifru_dstaddr
#define lifr_broadaddr lifr_lifru.lifru_broadaddr  /* broadcast addr. */
#define lifr_token     lifr_lifru.lifru_token      /* address token */
#define lifr_subnet    lifr_lifru.lifru_subnet     /* subnet prefix */
#define lifr_index     lifr_lifru.lifru_index      /* interface index */
#define lifr_flags     lifr_lifru.lifru_flags      /* flags */
#define lifr_metric    lifr_lifru.lifru_metric     /* metric */
#define lifr_mtu       lifr_lifru.lifru_mtu        /* mtu */
#define lifr_ip_muxid  lifr_lifru.lif_muxid[0]
#define lifr_arp_muxid lifr_lifru.lif_muxid[1]
#define lifr_nd        lifr_lifru.lifru_nd_req     /* SIOCLIF*ND */
#define lifr_ifinfo    lifr_lifru.lifru_ifinfo_req /* SIOC[GS]LIFLNKINFO */
#define lifr_zone      lifr_lifru.lifru_zone       /* SIOC[GS]LIFZONE */
};

SIOCSLIFADDR

SIOCGLIFADDR

SIOCSLIFDSTADDR

SIOCGLIFDSTADDR

SIOCSLIFFLAGS

SIOCGLIFFLAGS

SIOCGLIFCONF

SIOCGLIFNUM

SIOCSLIFMTU

SIOCGLIFMTU

SIOCSLIFMETRIC

SIOCGLIFMETRIC

SIOCGLIFMUXID

SIOCSLIFMUXID

SIOCGLIFINDEX

SIOCSLIFINDEX

SIOCGLIFZONE

SIOCSLIFZONE

SIOCLIFADDIF

SIOCLIFREMOVEIF

SIOCSLIFTOKEN

SIOCGLIFTOKEN

SIOCSLIFSUBNET

SIOCGLIFSUBNET

SIOCSLIFLNKINFO

SIOCGLIFLNKINFO

SIOCLIFDELND

SIOCLIFGETND

SIOCLIFSETND

SIOCSLIFUSESRC

SIOCGLIFUSESRC

SIOCGLIFSRCOF

SIOCTONLINK

SIOCTMYADDR

SIOCTMYSITE

The structure used by SIOCGLIFCONF has the form:

struct lifconf {


   sa_family_t     lifc_family;


   int             lifc_flags;       /* request specific


                                     /* interfaces */


   int             lifc_len;         /* size of assoc. buffer */


   union {


      caddr_t      lifcu_buf;


      struct lifreq *lifcu_req;


   } lifc_lifcu;
#define lifc_buf lifc_lifcu.lifcu_buf   /* buffer address */
#define lifc_req lifc_lifcu.lifcu_req   /* array of structs returned */
};

The structure used by SIOCGLIFNUM has the form:

struct lifnum {


   sa_family_t     lifn_family;


   int             lifn_flags;   /* req. specf. interfaces */


   int             lifn_count;   /* Result */
};

The structure used by SIOCTONLINK, SIOCTMYADDR and SIOCTMYSITE has the form:

struct sioc_addrreq {


   struct sockaddr_storage sa_addr; /* Address to test */


   int                     sa_res;  /* Result - 0/1 */
};

The structure used by SIOCGLIFSRCOF has the form:

 struct lifsrcof {


     uint_t  lifs_ifindex;   /* addr on this interface */


                             /* used as the src addr */


     size_t  lifs_maxlen;    /* size of buffer: input */


     size_t  lifs_len;       /* size of buffer: output */


     union {


            caddr_t lifsu_buf;


            struct  lifreq *lifsu_req;


   } lifs_lifsu;
#define lifs_buf lifs_lifsu.lifsu_buf /* buffer addr. */
#define lifs_req lifs_lifsu.lifsu_req /* array returned */
};

The following ioctl() calls are maintained for compatibility but only apply to IPv4 network interfaces, since the data structures are too small to hold an IPv6 address. Unless specified otherwise, the request takes an ifreq structure as its parameter. This structure has the form:

struct ifreq {
#define IFNAMSIZ	16


 char	ifr_name[IFNAMSIZ];              /* interface name - e.g. "hme0" */


 union {
	   struct sockaddr	ifru_addr;
	   struct sockaddr	ifru_dstaddr;
	   struct sockaddr	ifru_broadaddr;
	   short ifru_flags;
	   int   ifru_metric;
	   int   if_muxid[2];                   /* mux id's for arp and ip */
	   int   ifru_index;	                 /* interface index */
	} ifr_ifru;
#define ifr_addr      ifr_ifru.ifru_addr       /* address */
#define ifr_dstaddr   ifr_ifru.ifru_dstaddr    /* other end of p-to-p link */
#define ifr_broadaddr ifr_ifru.ifru_broadaddr  /* broadcast address */
#define ifr_flags     ifr_ifru.ifru_flags      /* flags */
#define ifr_index     ifr_ifru.ifru_index      /* interface index  */
#define ifr_metric    ifr_ifru.ifru_metric     /* metric */
};

SIOCSIFADDR

SIOCGIFADDR

SIOCSIFDSTADDR

SIOCGIFDSTADDR

SIOCSIFFLAGS

SIOCGIFFLAGS

SIOCGIFCONF

SIOCGIFNUM

SIOCSIFMTU

SIOCGIFMTU

SIOCSIFMETRIC

SIOCGIFMETRIC

SIOCGIFMUXID

SIOCSIFMUXID

SIOCGIFINDEX

SIOCSIFINDEX

The ifconf structure has the form:

struct ifconf {


 int	ifc_len;                        /* size of assoc. buffer */


 union {
	   caddr_t        ifcu_buf;
	   struct ifreq  *ifcu_req;
	} ifc_ifcu;
#define ifc_buf   ifc_ifcu.ifcu_buf   /* buffer address */
#define ifc_req   ifc_ifcu.ifcu_req   /* array of structs returned */
};

#define IFF_UP          0x0000000001    /* Address is up */
#define IFF_BROADCAST   0x0000000002    /* Broadcast address valid */
#define IFF_DEBUG       0x0000000004    /* Turn on debugging */
#define IFF_LOOPBACK    0x0000000008    /* Loopback net */
#define IFF_POINTOPOINT 0x0000000010    /* Interface is p-to-p */
#define IFF_NOTRAILERS  0x0000000020    /* Avoid use of trailers */
#define IFF_RUNNING     0x0000000040    /* Resources allocated */
#define IFF_NOARP       0x0000000080    /* No address res. protocol */
#define IFF_PROMISC     0x0000000100    /* Receive all packets */
#define IFF_ALLMULTI    0x0000000200    /* Receive all multicast pkts */
#define IFF_INTELLIGENT 0x0000000400    /* Protocol code on board */
#define IFF_MULTICAST   0x0000000800    /* Supports multicast */
#define IFF_MULTI_BCAST 0x0000001000    /* Multicast using broadcst. add. */
#define IFF_UNNUMBERED  0x0000002000    /* Non-unique address */
#define IFF_DHCPRUNNING 0x0000004000    /* DHCP controls interface */
#define IFF_PRIVATE     0x0000008000    /* Do not advertise */
#define IFF_NOXMIT      0x0000010000    /* Do not transmit pkts */
#define IFF_NOLOCAL     0x0000020000    /* No address - just on-link subnet */
#define IFF_DEPRECATED  0x0000040000    /* Address is deprecated */
#define IFF_ADDRCONF    0x0000080000    /* Addr. from stateless addrconf */
#define IFF_ROUTER      0x0000100000    /* Router on interface */
#define IFF_NONUD       0x0000200000    /* No NUD on interface */
#define IFF_ANYCAST     0x0000400000    /* Anycast address */
#define IFF_NORTEXCH    0x0000800000    /* Don't xchange rout. info */
#define IFF_IPV4        0x0001000000    /* IPv4 interface */
#define IFF_IPV6        0x0002000000    /* IPv6 interface */
#define IFF_NOFAILOVER  0x0008000000    /* in.mpathd test address */
#define IFF_FAILED      0x0010000000    /* Interface has failed */
#define IFF_STANDBY     0x0020000000    /* Interface is a hot-spare */
#define IFF_INACTIVE    0x0040000000    /* Functioning but not used */
#define IFF_OFFLINE     0x0080000000    /* Interface is offline */
#define IFF_XRESOLV     0x0100000000    /* IPv6 external resolver */
#define IFF_COS_ENABLED 0x0200000000    /* If CoS marking is supported */
#define IFF_PREFERRED   0x0400000000    /* Prefer as source address */
#define IFF_TEMPORARY   0x0800000000    /* RFC3041 */
#define IFF_FIXEDMTU    0x1000000000    /* MTU set with SIOCSLIFMTU */
#define IFF_VIRTUAL     0x2000000000    /* Cannot send/receive pkts */
#define IFF_DUPLICATE   0x4000000000    /* Local address in use */
#define IFF_IPMP        0x8000000000    /* IPMP IP interface */

ERRORS

EPERM

ENXIO

EBADADDR

EINVAL

EEXIST

SEE ALSO

ioctl(2), sockaddr(3SOCKET), streamio(4I), arp(4P), dlpi(4P), ip(4P), ip6(4P), ndp(4P), ifconfig(8), in.routed(8)