Linux Certif

Toute la documentation sur la certification Linux LPI

packet

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packet, PF_PACKET - ¥Ç¥Ð¥¤¥¹¥ì¥Ù¥ë¤Î¥Ñ¥±¥Ã¥È¥¤¥ó¥¿¡¼¥Õ¥§¡¼¥¹

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#include <sys/socket.h>




#include <netpacket/packet.h>




#include <net/ethernet.h>     /* the L2 protocols */



packet_socket = socket(PF_PACKET, int socket_type, int protocol);

ÀâÌÀ

packet ¥½¥±¥Ã¥È¤Ï¡¢¥Ç¥Ð¥¤¥¹¥É¥é¥¤¥Ð (OSI ¥ì¥¤¥ä 2) ¥ì¥Ù¥ë¤Ç À¸¤Î¥Ñ¥±¥Ã¥È (raw packet) ¤òÁ÷¼õ¿®¤¹¤ë¤¿¤á¤ËÍѤ¤¤é¤ì¤ë¡£ packet ¥½¥±¥Ã¥È¤ò»È¤¦¤È¡¢¥æ¡¼¥¶¡¼¶õ´Ö¤ÇʪÍýÁؤξå¤Ë ¥×¥í¥È¥³¥ë¥â¥¸¥å¡¼¥ë¤ò¼ÂÁõ¤¹¤ë¤³¤È¤¬¤Ç¤­¤ë¡£

socket_type ¤Ë¤Ï SOCK_RAW ¤È SOCK_DGRAM ¤Î¤¤¤º¤ì¤«¤ò»ØÄꤹ¤ë¡£ SOCK_RAW ¤Ï¥ê¥ó¥¯¥ì¥Ù¥ë¥Ø¥Ã¥À¤ò´Þ¤à raw ¥Ñ¥±¥Ã¥È¤ò¡¢ SOCK_DGRAM ¤Ï¥ê¥ó¥¯¥ì¥Ù¥ë¥Ø¥Ã¥À¤¬ºï½ü¤µ¤ì¤¿²Ã¹©ºÑ¤ß¥Ñ¥±¥Ã¥È¤ò¼¨¤¹¡£ ¥ê¥ó¥¯¥ì¥Ù¥ë¥Ø¥Ã¥À¾ðÊó¤Ï sockaddr_ll ¤Ç¶¦Ä̤Υե©¡¼¥Þ¥Ã¥È¤ÇÆþ¼ê¤Ç¤­¤ë¡£ protocol ¤Ë¤Ï IEEE 802.3 ¥×¥í¥È¥³¥ëÈÖ¹æ¤ò ¥Í¥Ã¥È¥ï¡¼¥¯¥Ð¥¤¥È¥ª¡¼¥À¡¼¤Ç»ØÄꤹ¤ë¡£ »ØÄê¤Ç¤­¤ë¥×¥í¥È¥³¥ë¤Î¥ê¥¹¥È¤Ï¡¢¥¤¥ó¥¯¥ë¡¼¥É¥Õ¥¡¥¤¥ë <linux/if_ether.h> ¤ò»²¾È¡£¥×¥í¥È¥³¥ë¤ò htons(ETH_P_ALL) ¤Ë¤¹¤ë¤È¡¢Á´¤Æ¤Î¥×¥í¥È¥³¥ë¤¬¼õ¿®¤µ¤ì¤ë¡£ ³°Éô¤«¤éÍ褿¥Ñ¥±¥Ã¥È¤Î¤¦¤Á»ØÄꤷ¤¿¥×¥í¥È¥³¥ë¤Î¤â¤Î¤Ï¡¢ ¥«¡¼¥Í¥ë¤Ë¼ÂÁõ¤µ¤ì¤Æ¤¤¤ë¥×¥í¥È¥³¥ë¤ËÅϤµ¤ì¤ëÁ°¤ÎÃʳ¬¤Ç¡¢ packet ¥½¥±¥Ã¥È¤ËÅϤµ¤ì¤ë¡£

packet ¥½¥±¥Ã¥È¤ò¥ª¡¼¥×¥ó¤Ç¤­¤ë¤Î¤Ï¡¢ ¼Â¸ú¥æ¡¼¥¶¡¼ID ¤¬ 0 ¤Î¥×¥í¥»¥¹¤«¡¢ CAP_NET_RAW ¥±¡¼¥Ñ¥Ó¥ê¥Æ¥£¤ò»ý¤Ä¥×¥í¥»¥¹¤À¤±¤Ç¤¢¤ë¡£

SOCK_RAW ¥Ñ¥±¥Ã¥È¤Ç¤Ï¡¢¥Ñ¥±¥Ã¥È¤ò¥Ç¥Ð¥¤¥¹¥É¥é¥¤¥Ð¤È¼õ¤±ÅϤ·¤¹¤ëºÝ¡¢ ¥Ñ¥±¥Ã¥È¥Ç¡¼¥¿¤ËÊѹ¹¤¬¹Ô¤ï¤ì¤ë¤³¤È¤Ï¤Ê¤¤¡£ ¥Ñ¥±¥Ã¥È¤Î¼õ¿®»þ¤Ë¤Ï¡¢¥¢¥É¥ì¥¹¤Î²òÀϤÀ¤±¤Ï¹Ô¤ï¤ì¡¢ ɸ½àŪ¤Ê sockaddr_ll ¥¢¥É¥ì¥¹¹½Â¤ÂΤËÅϤµ¤ì¤ë¡£¥Ñ¥±¥Ã¥È¤ÎÁ÷¿®»þ¤Ë¤Ï¡¢¥æ¡¼¥¶¤¬»ØÄꤹ¤ë ¥Ð¥Ã¥Õ¥¡¤ËʪÍýÁؤΥإåÀ¤¬´Þ¤Þ¤ì¤Æ¤¤¤ëɬÍפ¬¤¢¤ë¡£ ¥Ñ¥±¥Ã¥È¤Ï¤½¤Î¤Þ¤Þ½¤Àµ¤ò¼õ¤±¤º¤Ë¡¢¹Ô¤­À襢¥É¥ì¥¹¤«¤é·èÄꤵ¤ì¤ë ¥¤¥ó¥¿¡¼¥Õ¥§¡¼¥¹¤Î¥Í¥Ã¥È¥ï¡¼¥¯¥É¥é¥¤¥Ð¤Ë¥­¥å¡¼¥¤¥ó¥°¤µ¤ì¤ë¡£ ¥Ç¥Ð¥¤¥¹¥É¥é¥¤¥Ð¤Ë¤è¤Ã¤Æ¤Ï¡¢Â¾¤Î¥Ø¥Ã¥À¤ò¾ï¤ËÄɲ乤ë¤â¤Î¤â¤¢¤ë¡£ SOCK_RAW ¤Ï Linux 2.0 ¤Î obosolete ¤Ê PF_INET/SOCK_PACKET ¤È»÷¤Æ¤¤¤ë¤¬¡¢¸ß´¹À­¤¬¤¢¤ë¤ï¤±¤Ç¤Ï¤Ê¤¤¡£

SOCK_DGRAM ¤Ï¤ä¤ä¹â°Ì¤Î¥ì¥Ù¥ë¤ÇÆ°ºî¤¹¤ë¡£ÊªÍý¥Ø¥Ã¥À¤Ï¡¢¥Ñ¥±¥Ã¥È¤¬¥æ¡¼¥¶¡¼¤Ë ÅϤµ¤ì¤ëÁ°¤Ëºï½ü¤µ¤ì¤ë¡£ SOCK_DGRAM ¤Î packet ¥½¥±¥Ã¥È¤òÄ̤·¤ÆÁ÷¤é¤ì¤ë¥Ñ¥±¥Ã¥È¤Ï¡¢ sockaddr_ll ¤Î¹Ô¤­À襢¥É¥ì¥¹¤Î¾ðÊó¤Ë´ð¤Å¤­¡¢Å¬ÀÚ¤ÊʪÍýÁؤΥإåÀ¤¬Éղ䵤ì¤Æ¤«¤é¡¢ ¥­¥å¡¼¤ËÁ÷¤é¤ì¤ë¡£

¥Ç¥Õ¥©¥ë¥È¤Ç¤Ï¡¢»ØÄꤷ¤¿¥×¥í¥È¥³¥ë·¿¤Î¥Ñ¥±¥Ã¥È¤Ï¤¹¤Ù¤Æ packet ¥½¥±¥Ã¥È¤ËÁ÷¤é¤ì¤ë¡£ÆÃÄê¤Î¥¤¥ó¥¿¡¼¥Õ¥§¡¼¥¹¤«¤é¤Î¥Ñ¥±¥Ã¥È¤À¤±¤ò ¼èÆÀ¤·¤¿¤¤¾ì¹ç¤Ë¤Ï¡¢ struct sockaddr_ll ¤Ë¥¢¥É¥ì¥¹¤ò»ØÄꤷ¤Æ bind(2) ¤ò¸Æ¤Ó¡¢ packet ¥½¥±¥Ã¥È¤ò¤½¤Î¥¤¥ó¥¿¡¼¥Õ¥§¡¼¥¹¤Ë·ë¤ÓÉÕ¤±¤ë (¥Ð¥¤¥ó¥É¤¹¤ë)¡£ ¥Ð¥¤¥ó¥É¤ÎºÝ¤Ë¤Ï¡¢¥¢¥É¥ì¥¹¥Õ¥£¡¼¥ë¥É¤Î¤¦¤Á sll_protocol ¤È sll_ifindex ¤À¤±¤¬ÍѤ¤¤é¤ì¤ë¡£

connect(2) Áàºî¤Ï packet ¥½¥±¥Ã¥È¤Ç¤Ï¥µ¥Ý¡¼¥È¤µ¤ì¤Æ¤¤¤Ê¤¤¡£

MSG_TRUNC ¥Õ¥é¥°¤¬ recvmsg(2), recv(2), recvfrom(2) ¤ËÅϤµ¤ì¤ë¤È¡¢ (¥Ð¥Ã¥Õ¥¡¥µ¥¤¥º¤è¤êÂ礭¤«¤Ã¤¿¤È¤·¤Æ¤â) ¾ï¤Ë¼ÂºÝ¤ËÄÌ¿®¤µ¤ì¤¿ ¥Ñ¥±¥Ã¥È¤ÎŤµ¤¬ÊÖ¤µ¤ì¤ë¡£

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sockaddr_ll ¤Ï¥Ç¥Ð¥¤¥¹¤Ë°Í¸¤·¤Ê¤¤ÊªÍýÁؤΥ¢¥É¥ì¥¹¤Ç¤¢¤ë¡£

struct sockaddr_ll {

    unsigned short sll_family;   /* ¾ï¤Ë AF_PACKET */

    unsigned short sll_protocol; /* ʪÍýÁؤΥץí¥È¥³¥ë */

    int            sll_ifindex;  /* ¥¤¥ó¥¿¡¼¥Õ¥§¡¼¥¹ÈÖ¹æ */

    unsigned short sll_hatype;   /* ¥Ø¥Ã¥À¼ïÊÌ */

    unsigned char  sll_pkttype;  /* ¥Ñ¥±¥Ã¥È¼ïÊÌ */

    unsigned char  sll_halen;    /* ¥¢¥É¥ì¥¹¤ÎŤµ */

    unsigned char  sll_addr[8];  /* ʪÍýÁؤΥ¢¥É¥ì¥¹ */

};

sll_protocol ¤Ïɸ½àŪ¤Ê¥¤¡¼¥µ¥Í¥Ã¥È¥×¥í¥È¥³¥ë¤Î¥¿¥¤¥×¤Ç¡¢ ¥Í¥Ã¥È¥ï¡¼¥¯¥Ð¥¤¥È¥ª¡¼¥À¡¼¤Çµ­½Ò¤¹¤ë¡£ ¥¤¥ó¥¯¥ë¡¼¥É¥Õ¥¡¥¤¥ë <linux/if_ether.h> ¤ÇÄêµÁ¤µ¤ì¤Æ¤¤¤ë¡£ ¤³¤ì¤¬¤³¤Î¥½¥±¥Ã¥È¤Î¥×¥í¥È¥³¥ë¤Î¥Ç¥Õ¥©¥ë¥È¤È¤Ê¤ë¡£

sll_ifindex ¤Ï¤½¤Î¥¤¥ó¥¿¡¼¥Õ¥§¡¼¥¹¤Î interface index ¤Ç¤¢¤ë (netdevice(7) ¤ò»²¾È)¡£ 0 ¤ÏǤ°Õ¤Î¥¤¥ó¥¿¡¼¥Õ¥§¡¼¥¹¤Ë¥Þ¥Ã¥Á¤¹¤ë (¥Ð¥¤¥ó¥É»þ¤Î¤ßÍ­¸ú)¡£

sll_hatype ¤Ï¡¢¥¤¥ó¥¯¥ë¡¼¥É¥Õ¥¡¥¤¥ë <linux/if_arp.h> ¤ÇÄêµÁ¤µ¤ì¤Æ¤¤¤ë ARP ¼ïÊ̤Ǥ¢¤ë¡£

sll_pkttype ¤Ï¥Ñ¥±¥Ã¥È¼ïÊ̤Ǥ¢¤ë¡£»ØÄê¤Ç¤­¤ë¼ïÊ̤ϰʲ¼¤Î¤¤¤º¤ì¤«¤Ç¤¢¤ë: PACKET_HOST (¥í¡¼¥«¥ë¥Û¥¹¥È¸þ¤±¤Î¥Ñ¥±¥Ã¥È)¡¢ PACKET_BORADCAST (ʪÍýÁØ¤Î¥Ö¥í¡¼¥É¥­¥ã¥¹¥È¥Ñ¥±¥Ã¥È)¡¢ PACKET_MULTICAST (ʪÍýÁؤΥޥë¥Á¥­¥ã¥¹¥È¥¢¥É¥ì¥¹¤ËÁ÷¤ë¥Ñ¥±¥Ã¥È)¡¢ PACKET_OTHERHOST (¾¤Î¥Û¥¹¥È¤Ë¸þ¤±¤é¤ì¤¿¥Ñ¥±¥Ã¥È¤Î¤¦¤Á¡¢ ̵º¹Ê̥⡼¥É (promiscuous mode: ¸å½Ò) ¤Î¥Ç¥Ð¥¤¥¹¥É¥é¥¤¥Ð¤Ë¤è¤êÊä­¤µ¤ì¤¿¤â¤Î)¡¢ PACKET_OUTGOING (¥í¡¼¥«¥ë¥Û¥¹¥È¤«¤éȯ¿®¤µ¤ì¡¢ packet ¥½¥±¥Ã¥È¤Ë¥ë¡¼¥×¥Ð¥Ã¥¯¤·¤Æ¤­¤¿¥Ñ¥±¥Ã¥È)¡£ ¤³¤ì¤é¤Î¼ïÊ̤¬°ÕÌ£¤ò»ý¤Ä¤Î¤Ï¼õ¿®»þ¤Î¤ß¤Ç¤¢¤ë¡£

sll_addr ¤È sll_halen ¤Ï¡¢ÊªÍýÁؤΠ(¤Ä¤Þ¤ê IEEE 802.3 ¤Î) ¥¢¥É¥ì¥¹¤È¤½¤ÎŤµ¤Ç¤¢¤ë¡£ ¸·Ì©¤Ê²ò¼á¤Ï¥Ç¥Ð¥¤¥¹¤Ë°Í¸¤¹¤ë¡£

¥Ñ¥±¥Ã¥È¤òÁ÷¤ë¾ì¹ç¤Ï¡¢ sll_family, sll_addr, sll_halen, sll_ifindex ¤ò»ØÄꤹ¤ì¤Ð½½Ê¬¤Ç¤¢¤ë¡£ ¤½¤Î¾¤Î¥Õ¥£¡¼¥ë¥É¤Ï 0 ¤Ë¤·¤Æ¤ª¤¯¤Ù¤­¤Ç¤¢¤ë¡£ sll_hatype ¤È sll_pkttype ¤Ë¤Ï¼õ¿®¤·¤¿¥Ñ¥±¥Ã¥È¤Î¾ðÊó¤¬ÀßÄꤵ¤ì¤ë¡£ ¥Ð¥¤¥ó¥É¤ÎºÝ¤Ë¤Ï¡¢ sll_protocol ¤È sll_ifindex ¤À¤±¤¬»ÈÍѤµ¤ì¤ë¡£

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packet ¥½¥±¥Ã¥È¤Ï¡¢ÊªÍýÁؤΥޥë¥Á¥­¥ã¥¹¥È¤ä ̵º¹Ê̥⡼¥É (promiscuous mode) ¤òÀßÄꤷ¤Æ»È¤¦¤³¤È¤¬¤Ç¤­¤ë¡£ ¤³¤ì¤Ë¤Ï SOL_PACKET ¤È°Ê²¼¤Î¥ª¥×¥·¥ç¥ó¤Î¤¤¤º¤ì¤«¤ò»ØÄꤷ¤Æ setsockopt(2) ¤ò¸Æ¤Ù¤Ð¤è¤¤¡£ ¥Ð¥¤¥ó¥É¤òÄɲ乤ë¾ì¹ç¤Ï PACKET_ADD_MEMBERSHIP ¤Ç¤¢¤ê¡¢¼è¤êµî¤ë¾ì¹ç¤Ï PACKET_DROP_MEMBERSHIP ¤Ç¤¢¤ë¡£¤³¤ì¤é¤Ï¤¤¤º¤ì¤â packet_mreq ¹½Â¤ÂΤò°ú¤­¿ô¤Ë¼è¤ë¡£

struct packet_mreq {

    int            mr_ifindex;    /* ¥¤¥ó¥¿¡¼¥Õ¥§¡¼¥¹ÈÖ¹æ */

    unsigned short mr_type;       /* Æ°ºî */

    unsigned short mr_alen;       /* ¥¢¥É¥ì¥¹¤ÎŤµ */

    unsigned char  mr_address[8]; /* ʪÍýÁؤΥ¢¥É¥ì¥¹ */

};

mr_ifindex ¤Ï¡¢¥¹¥Æ¡¼¥¿¥¹¤òÊѹ¹¤·¤¿¤¤¥¤¥ó¥¿¡¼¥Õ¥§¡¼¥¹¤Î ¥¤¥ó¥¿¡¼¥Õ¥§¡¼¥¹ÈÖ¹æ¤Ç¤¢¤ë¡£ mr_type ¥Ñ¥é¥á¡¼¥¿¤Ï¼Â¹Ô¤¹¤ëÆ°ºî¤ò»ØÄꤹ¤ë: PACKET_MR_PROMISC ¤Ï¡¢¶¦Í­¤·¤Æ¤¤¤ëÇÞÂΤ«¤é¤ÎÁ´¤Æ¤Î¥Ñ¥±¥Ã¥È¤ò¼õ¿®¤Ç¤­¤ë¤è¤¦¤Ë¤¹¤ë (¤·¤Ð¤·¤Ð ``̵º¹Ê̥⡼¥É (promiscuous mode)'' ¤È¸Æ¤Ð¤ì¤ë)¡£ PACKET_MR_MULTICAST ¤Ï¡¢¤½¤Î¥½¥±¥Ã¥È¤ò¡¢ mr_address ¤È mr_alen ¤Ç»ØÄꤵ¤ì¤ëʪÍýÁؤΥޥë¥Á¥­¥ã¥¹¥È¥Ö¥ë¡¼¥×¤Ë¥Ð¥¤¥ó¥É¤¹¤ë¡£ PACKET_MR_ALLMULTI ¤Ï socket ¤ò up ¤Ë¤·¤Æ¡¢¤½¤Î¥¤¥ó¥¿¡¼¥Õ¥§¡¼¥¹¤ËÅþ㤷¤¿¤¹¤Ù¤Æ¤Î ¥Þ¥ë¥Á¥­¥ã¥¹¥È¥Ñ¥±¥Ã¥È¤ò¼õ¿®¤Ç¤­¤ë¤è¤¦¤Ë¤¹¤ë¡£

ÀΤ«¤é¤¢¤ë ioctl ¤À¤±¤Ç¤Ê¤¯¡¢ SIOCSIFFLAGS, SIOCADDMULTI, SIOCDELMULTI ¤òƱ¤¸ÌÜŪ¤ËÍѤ¤¤ë¤³¤È¤¬¤Ç¤­¤ë¡£

ioctl

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ENOTCONN

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EINVAL

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ENOENT

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PF_PACKET ¤Ï Linux 2.2 ¤Î¿·µ¡Ç½¤Ç¤¢¤ë¡£¤³¤ì¤è¤ê¸Å¤¤¥Ð¡¼¥¸¥ç¥ó¤Î Linux ¤Ç¤Ï SOCK_PACKET ¤Î¤ß¤ò¥µ¥Ý¡¼¥È¤·¤Æ¤¤¤¿¡£

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#include <asm/types.h>

#include <linux/if_packet.h>

#include <linux/if_ether.h>  /* The L2 protocols */

Ãí°Õ

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SOCK_DGRAM packet ¥½¥±¥Ã¥È¤Ï¡¢IEEE 802.3 ¥Õ¥ì¡¼¥à¤Î IEEE 802.2 LLC ¥Ø¥Ã¥À¤Î À¸À®¤ä²òÀϤò¹Ô¤ª¤¦¤È¤·¤Ê¤¤¡£ ETH_P_802_3 ¤¬Á÷¿®¥×¥í¥È¥³¥ë¤Ë»ØÄꤵ¤ì¤ë¤È¡¢¥«¡¼¥Í¥ë¤Ï 802.3 ¥Õ¥ì¡¼¥à¤ò À¸À®¤·¤Æ length ¥Õ¥£¡¼¥ë¥É¤Ë½ñ¤­¹þ¤à¡£ ´°Á´¤Ë½àµò¤·¤¿¥Ñ¥±¥Ã¥È¤òÆÀ¤ë¤¿¤á¤Ë¤Ï¥æ¡¼¥¶¡¼¤¬ LLC ¥Ø¥Ã¥À¤ò Í¿¤¨¤ëɬÍפ¬¤¢¤ë¡£ÅþÃ夷¤¿ 802.3 ¥Ñ¥±¥Ã¥È¤Ç¤Ï¡¢ DSAP/SSAP protocol ¤Î³Æ¥Õ¥£¡¼¥ë¥É¤Ï¿½Å²½ (multiplex) ¤µ¤ì¤Æ¤¤¤Ê¤¤¡£ Âå¤ï¤ê¤Ë¤³¤ì¤é¤Ï LLC ¥Ø¥Ã¥À¤¬Á°ÃÖ¤µ¤ì¤¿ ETH_P_802_2 ¥×¥í¥È¥³¥ë¤È¤·¤ÆÍ¿¤¨¤é¤ì¤ë¡£¤·¤¿¤¬¤Ã¤Æ¡¢ ETH_P_802_3 ¤Ë¥Ð¥¤¥ó¥É¤¹¤ë¤³¤È¤Ï¤Ç¤­¤Ê¤¤¡£¤«¤ï¤ê¤Ë ETH_P_802_2 ¤Ë¥Ð¥¤¥ó¥É¤·¡¢¼«Ê¬¼«¿È¤Ç¥×¥í¥È¥³¥ë¤Î¿½Å²½¤ò¹Ô¤¦¤³¤È¡£ Á÷¿®¤Î¥Ç¥Õ¥©¥ë¥È¤Ï¡¢¥×¥í¥È¥³¥ë¥Õ¥£¡¼¥ë¥É¤ò»ý¤Ä ɸ½à¤Î Ethernet DIX encapsulation ¤Ç¤¢¤ë¡£

packet ¥½¥±¥Ã¥È¤ÏÆþ½ÐÎϤΠfirewall chain ¤Ë±Æ¶Á¤ò¤¦¤±¤Ê¤¤¡£

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Linux 2.0 ¤Ç¤Ï¡¢ packet ¥½¥±¥Ã¥È¤òÆÀ¤ëÊýË¡¤Ï socket(PF_INET, SOCK_PACKET, protocol) ¤ò¸Æ¤Ö¤ä¤êÊý¤·¤«¤Ê¤«¤Ã¤¿¡£¤³¤ÎÊýË¡¤Ï¤Þ¤À¥µ¥Ý¡¼¥È¤µ¤ì¤Æ¤¤¤ë¤¬¡¢ ÍѤ¤¤Ê¤¤¤³¤È¤ò¶¯¤¯¿ä¾©¤¹¤ë¡£¸½ºß¤ÎÊýË¡¤È¤Î¼ç¤Ê°ã¤¤¤Ï¡¢ SOCK_PACKET ¤Ç¤Ï¥¤¥ó¥¿¡¼¥Õ¥§¡¼¥¹¤Î»ØÄê¤Ë¸Å¤¤ struct sockaddr_pkt ¤òÍѤ¤¤ëÅÀ¤Ç¤¢¤ë¡£¤³¤ì¤Ë¤ÏʪÍýÁؤ«¤é¤ÎÆÈΩÀ­¤¬¤Ê¤¤¡£

struct sockaddr_pkt {

    unsigned short spkt_family;

    unsigned char  spkt_device[14];

    unsigned short spkt_protocol;

};

spkt_family ¤Ï¥Ç¥Ð¥¤¥¹¤Î¥¿¥¤¥×¡¢ spkt_protocol ¤Ï <sys/if_ether.h> ¤ÇÄêµÁ¤µ¤ì¤Æ¤¤¤ë IEEE 802.3 ¥×¥í¥È¥³¥ë¥¿¥¤¥×¡¢ spkt_device ¤Ï¥Ç¥Ð¥¤¥¹¤Î̾Á°¤ò NULL ½ªÃ¼¤µ¤ì¤¿Ê¸»úÎó¤ÇÍ¿¤¨¤¿¤â¤Î (Îã: eth0) ¤Ç¤¢¤ë¡£

¤³¤Î¹½Â¤ÂÎ¤Ï obsolete ¤Ç¤¢¤ê¡¢ ¿·¤·¤¯¥³¡¼¥É¤ò½ñ¤¯»þ¤Ë¤ÏÍѤ¤¤ë¤Ù¤­¤Ç¤Ê¤¤¡£

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#ifndef SOL_PACKET

#define SOL_PACKET 263

#endif

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