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inet — ???󥿡??ͥåȥץ??ȥ????ե??ߥ?

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#include <sys/types.h> #include <netinet/in.h>

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???󥿡??ͥåȥץ??ȥ????ե??ߥ??? Internet Protocol (IP) ?ȥ??󥹥ݡ????ؤξ??˰??֤??????󥿡??ͥåȥ??ɥ쥹?ե????ޥåȤ? ???Ѥ????ץ??ȥ??뷲?Ǥ??? ???󥿡??ͥåȥե??ߥ??ϡ? SOCK_STREAM, SOCK_DGRAM ?????? SOCK_RAW ?????åȥ????פΤ????Υץ??ȥ????Υ??ݡ??Ȥ??󶡤??ޤ??? SOCK_RAW ???󥿥ե??????? IP ?ץ??ȥ????ؤΥ??????????󶡤??ޤ???

???ɥ??å?????

???󥿡??ͥåȥ??ɥ쥹?? 4 ?Х??Ȥ??礭???Ǥ??ꡢ ?ͥåȥ??ɸ???ե????ޥåȤdz?Ǽ?????Ƥ??ޤ? ( VAX ?Ǥϡ???ɡ??Х??Ȥν??????դˤ??????ΤǤ?)?? ???󥯥롼?ɥե????? ⟨netinet/in.h⟩ ?Ǥϡ????Υ??ɥ쥹?? ??ʬ???줿?????ΤȤ??????????Ƥ??ޤ???

???󥿡??ͥåȥץ??ȥ????ե??ߥ??˷??礵?줿?????åȤϡ????? ???ɥ??å??󥰹?¤?Τ????Ѥ??ޤ???

struct sockaddr_in {
	u_char	sin_len;
	u_char	sin_family;
	u_short	sin_port;
	struct	in_addr sin_addr;
	char	sin_zero[8];
};

???????å????????Ф??? “?磻???ɥ?????” ?ޥå??󥰤θ??̤????????硢 INADDR_ANY ???????륢?ɥ쥹???Ѥ??ơ? ?????åȤ????????뤳?Ȥ??Ǥ??ޤ??? connect(2) ???뤤?? sendto(2) ?θƤӽФ???Ϳ???륢?ɥ쥹?Ȥ??ơ? “???Υۥ???” ????̣???뤿???ˡ? INADDR_ANY ??Ϳ???Ƥ⹽???ޤ????? ?⤷?ǽ餫???ͥåȥ?????֥????ɥ??㥹?Ȥ򥵥ݡ??Ȥ????褦?????? ?????Ƥ????С? ???̤Υ??ɥ쥹?Ǥ??? INADDR_BROADCAST ?????ץ饤?ޥ??ͥåȥ?????Υ֥????ɥ??㥹?ȥ??ɥ쥹??ɽ??ά???Ȥ??? ???????Ƥ??ޤ???

?ץ??ȥ???

???󥿡??ͥåȥץ??ȥ????ե??ߥ??ϡ? IP ?ͥåȥ???ץ??ȥ??롢 ???󥿡??ͥåȥ????ȥ????????å??????ץ??ȥ??? (ICMP) ?????󥿡??ͥåȥ??롼?ץޥͥ??????ȥץ??ȥ??? (IGMP) ???ȥ??󥹥ߥå????󥳥??ȥ??????ץ??ȥ??? (TCP) ???????ӥ桼???ǡ??????????ץ??ȥ??? (UDP) ?????ʤ??ޤ??? TCP ?? SOCK_STREAM ???֥??ȥ饯???????򥵥ݡ??Ȥ??뤿???˻Ȥ??졢 UDP ?? SOCK_DGRAM ???֥??ȥ饯???????򥵥ݡ??Ȥ??뤿???˻Ȥ????ޤ??? IP ???Ф??? raw ???󥿥ե????????? SOCK_RAW ?????פΥ??󥿡??ͥåȥ????åȤ????????뤳?Ȥˤ??? ???Ѳ?ǽ?Ǥ??? ICMP ???å??????ץ??ȥ??뤬 raw ?????åȤ??饢????????ǽ?Ǥ???

32 ?ӥåȤΥ??󥿡??ͥåȥ??ɥ쥹?ϥͥåȥ?????ȥۥ??????? ξ?????ޤ??Ǥ??ޤ??? ???????ʤ??顢???ɥ쥹???Ф???ľ?ܸ??????뤳?ȤϿ侩?????ޤ????? ?ɤ????Ƥ⥢?ɥ쥹?򤽤? 2 ?Ĥ???ʬ??ʬ?䤹??ɬ?פΤ????ץ????????? ?????ˡ????? ioctl(2) ???ޥ??ɤ????󥿡??ͥåȥɥᥤ???Υǡ????????ॽ???åȸ????? ?󶡤????Ƥ??ޤ??? ???????? SIOCIFADDR ???ޥ??? ( intro(4) ?򻲾? ) ??Ʊ?????????????ޤ???

SIOCSIFNETMASK

???󥿥ե??????Υͥåȥ???ޥ????????ꤷ?ޤ??? ?ͥåȥ???ޥ????ϥ??ɥ쥹?Υͥåȥ?????????????ޤ??? ?⤷???줬???ɥ쥹?????פ???????????¿?????ɥ쥹???ޤ??ʤ顢 ???֥ͥåȤ??Ȥ????Ƥ??ޤ???

SIOCGIFNETMASK

???󥿥ե??????Υͥåȥ???ޥ????????ޤ???

?롼?ƥ?????

???󥿡??ͥåȥץ??ȥ????θ??ߤμ????ϡ??ȥ??󥶥??????? TCP (Transaction TCP) ?????ӷ?ϩ?? MTU ???? (Path MTU Discovery) ??ɬ?פʤ??????Υ????ɥġ??????ɾ??????Ф??붯?Ϥ? ?????å??󥰤??󶡤??뤿???ˡ??롼?ƥ??󥰥ơ??֥????Ф??? ?????Ĥ???Ĵ?????ޤ??Ǥ??ޤ??? ???˼????ѹ????Ǥ????פǤ? :

1. RTF_CLONING ?ե饰?դ????뤤?ϥޥ??????㥹?Ȥν????? ?ʳ??? IP ??ϩ?? RTF_PRCLONING ?ե饰??????Ū??Ω?Ƥ????ޤ? (?????? “?ץ??ȥ??륯?????˥???” ?ȸƤФ??ޤ???)
2. ???? IP ??ϩ?ؤκǸ??λ??Ȥ?????Ƥ??????硢 ???η?ϩ???????Τ褦?ʷ?ϩ?򥳥ԡ????뤳?Ȥˤ??????????줿???ɤ????? ?????????ޤ??? ?⤷?????Ǥ????С? RTF_PROTO3 ?ե饰??Ω?Ƥ??졢net.inet.ip.rtexpire ?ð????˾õ?????褦?? ̵?????Τ????Υ????ޤ????????????ޤ??? ???Τ褦?ʷ?ϩ???Ƥӻ??Ȥ??????ȡ??ե饰?ȥ????ޤϥꥻ?åȤ????ޤ???
3. 10 ʬ?? 1 ?󡢤??뤤?ϥ????ͥ??Υ롼?ƥ??󥰥ơ??֥??˴????ڤ?ľ???? ??ϩ??¸?ߤ????Ȥ????˥????ͥ륿???ॢ???Ȥ??¹Ԥ??졢 ?????ڤ??η?ϩ?????????ޤ???

?????å??夵???Ƥ?????ϩ???礭???ʤ??᤮?????硢 net.inet.ip.rtexpire ???ͤ??ѹ????뤿???? ưŪ?ʽ??????¹Ԥ????ޤ??? ?????ڤ??õ??μ¹Ը??ˡ?net.inet.ip.rtmaxcache ????¿?????η?ϩ?????Ȥ????ʤ??ޤ޻ĤäƤ??????硢 rtexpire ?? 3/4 ?ˤ??졢????????Ĺ?????¤????? ???٤Ƥη?ϩ?δ??¤?Ĵ???????ޤ??? ?Ǿ??? rtexpire ?? (net.inet.ip.rtminexpire) ?λ??ꤪ???? ???κ︺?? 10 ʬ?? 1 ?󤪤??˵??????褦?????¤??뤳?Ȥˤ??ꡢ ???Υץ??????θ??̤Ϥ????餫???????ʤ??ޤ???

???餫?γ????ץ????????? ?ץ??ȥ??륯???????Ǻ????줿??ϩ?? ???ꥸ?ʥ??η?ϩ?????????????硢 ?ֻҤη?ϩ?פϺ????????ޤ??? (?ºݤΤȤ??????????ϡ??ץ??ȥ????׵᥯?????˥󥰤򥵥ݡ??Ȥ??? ?롼?ƥ??󥰥????ɤˤ?????????Ū?ʥᥫ?˥????Ǥ???)

?ץ??ȥ??륯?????˥󥰤ˤ??????????줿?ΤǤϤʤ???ϩ?????????? ???ߤϹԤʤ????ޤ????? ??????????Ū?Ǥ??ꡢ ?????Υ롼?ƥ??󥰥ץ??????䡢???뤤?? ???????? (???Ȥ??? ???????ͥåȤˤ????? ARP) ?δ??????ˤ????????ꤵ???ޤ???

???????Υͥåȥ????ư???????????Υᥫ?˥??????Ѥ??Ʒ?ϩ?Υ??????˥??? ???Ԥʤ??ޤ??? ?äˤ??밸??????????Ĺ???ַ?³??????ϩ?λ??Ȥ???ʬ???Ȥǥ????å??? ?????ץ??ȥ??? ( TCP ?? UDP ?Τ褦?? ) ?ϡ????Υᥫ?˥???????ư???뤭?ä????Ȥʤ??ޤ??? ???????????????????????줿???ΤǤ????ե???ɤ??줿???ΤǤ??졢 ???? IP ?ѥ??åȤ??ȡ????Υᥫ?˥????ϵ?ư???ޤ?????

MIB ?ѿ?

sysctl(3) MTB ?? net.inet ?֥??????ˤϡ?¿???? ?ѿ????????????Ƥ??ޤ??? ?ȥ??󥹥ݡ??ȥץ??ȥ????ˤ??ꥵ?ݡ??Ȥ??????ѿ? (?ơ??Υޥ˥奢???ڡ????򻲾Ȥ??Ƥ???????) ?˲ä??????ΰ???Ū???ѿ????????????Ƥ??ޤ???

IPCTL_FORWARDING

(ip.forwarding) ?֡?????: IP ?ѥ??åȤΥե???ǥ??󥰤???ǽ?ˤ??? / ???????? (?ǥե????ȤǤϥ????ͥ????ꥪ?ץ????? GATEWAY ?ˤ????ޤ?)??

IPCTL_SENDREDIRECTS

(ip.redirect) ?֡?????: ?ե???ɤǤ??ʤ? IP ?ѥ??åȤˤĤ??? ICMP ???????쥯?Ȥ????Ф??? / ???Ф??ʤ? (?ǥե????ȤϿ?)??

IPCTL_DEFTTL

(ip.ttl) ??????: ???˽ФƤ??? IP ?ѥ??åȤΥǥե????Ȥ???¸???֡?

IPCTL_SOURCEROUTE

(ip.sourceroute) ?֡?????: ??????ϩ???椵?줿 IP ?ѥ??åȤΥե???ɤ? ??ǽ?ˤ??? / ???????? (?ǥե????Ȥϵ?)??

IPCTL_RTEXPIRE

(ip.rtexpire) ??????: ?ץ??ȥ??륯?????󤵤줿 IP ??ϩ?Ρ??Ǹ??λ??Ȥ???λ??????????ñ?̤? ??¸???? (?ǥե????Ȥ? 1 ????)?? ?嵭?Τ褦?ˡ??????ͤ?ưŪ???Ѳ????ޤ???

IPCTL_RTMINEXPIRE

(ip.rtminexpire) ??????: ip.rtexpire ?κǾ??? (?ǥե????Ȥ? 10 ??)?? ?????ͤϥ桼???ˤ????ѹ????Ф??Ƥϸ??̤??ʤ????嵭?Τ褦??ưŪĴ???? ?¤????Ƥ??ޤ???

IPCTL_RTMAXCACHE

(ip.rtmaxcache) ??????: ?????å??夵?졢???Ļ??Ȥ??줺?????ĥץ??ȥ??? ???????󤵤줿??ϩ?Ρ?ưŪ??Ĵ???򳫻Ϥ????ȥꥬ???٥? (?ǥե????Ȥ? 128)??

??Ϣ????

ioctl(2), socket(2), sysctl(3), icmp(4), igmp(4), intro(4), ip(4), tcp(4), ttcp(4), udp(4) An Introductory 4.3 BSD Interprocess Communication Tutorial, PS1, 7. An Advanced 4.3 BSD Interprocess Communication Tutorial, PS1, 8.

?ٹ?

???󥿡??ͥåȥץ??ȥ????Υ??ݡ??Ȥϡ????󥿡??ͥåȥץ??ȥ????? ȯŸ?˽?°???Ƥ??ޤ????桼???ϸ??ߤμ????ξܺ٤˰?¸???ƤϤʤ餺?? ?ष?????????ݡ??Ȥ??줿?????ӥ??˰?¸???٤??Ǥ???

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inet ?ץ??ȥ??륤?󥿥ե??????? 4.2BSD ???о줷?ޤ????? “?ץ??ȥ??륯?????˥???” ?Υ????ɤ? FreeBSD 2.1 ???о줷?ޤ?????