¡¾×ªÌûLINUX¡¿netfilterÖеÄconntrackÄÚºËÔĶÁ±Ê¼Ç(3)
2008-07-07 22:06
PREROUTING£ºip_conntrack_defrag à ip_conntrack_in
1£¬ip_conntrack_defrag:
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/* Èô±¨ÎÄ·ÖÆ¬£¬Ôò µ÷ÓÃip_ct_gather_frags ×é×°±¨ÎÄ£¬Èç¹ûËùÓÐ·ÖÆ¬¾ùÒѵ½´ï£¬pskbÖ¸ÏòÐÂÉú³ÉµÄ±¨ÎÄ£¬¼ÌÐøÑØ×ÅHOOKÁ´½øÐÐÏÂÒ»²½´¦Àí£»·ñÔòΪ¿Õ£¬±¨Îı»»º´æµÈ´ýÏÂÒ»·ÖƬµ½À´*/
if ((*pskb)->nh.iph->frag_off & htons(IP_MF|IP_OFFSET)) {
*pskb = ip_ct_gather_frags(*pskb,
hooknum == NF_IP_PRE_ROUTING ?
IP_DEFRAG_CONNTRACK_IN :
IP_DEFRAG_CONNTRACK_OUT);
if (!*pskb)
return NF_STOLEN;
}
return NF_ACCEPT;
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3, resolve_normal_ct£º
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/*1,½«Êý¾Ý°üµÄÄÚÈÝת»¯³ÉÏàÓ¦µÄtuple£¬¶ÔÓÚºÍÐÒéÏà¹ØµÄ²¿·Ö£¬Èç¶Ë¿Ú£¬Ôòµ÷ÓÃÏà¹ØÐÒéµÄ´¦Àíº¯Êýpkt_to_tuple*/
if (!ip_ct_get_tuple(skb->nh.iph, skb, skb->nh.iph->ihl*4,
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Linux LVM µÄʹÓÃÏê½â
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ÎÒ´ó¸ÅÁ˽âÏÂÀ´ÊÇÕâÑùµÄ¡£¶ÔÓÚlinuxµÄÎļþϵͳÀ´Ëµ£¬ÏÂÃæÓкܶà“Îļþ”£¬ÕâЩ“Îļþ”°üÀ¨ÁËÉ豸¡¢´ÅÅÌÇý¶¯Æ÷µÈµÈ¡£±ÈÈç"\"±íʾ¸ùĿ¼£¬¶ø\userÊÇÓÃÀ´×°Õû¸ö²Ù ......
UNIX/Linux ϵͳ´ÅÅÌ ¿Õ¼ä¼à¿Ø ×Ô¶¯»¯½Å±¾ ʾÀý
1. ·ÖÇø¼à¿Ø /root/disktab ÎļþʾÀý
2. checkdisk ½Å±¾³õʼ»¯²¿·Ö
3. checkdisk ½Å±¾·ÖÎö /root/disktab Îļþ²¿·Ö
4.ÖеĽű¾ÊµÏÖÁËʵʱ¼à¿Ø²¢¼ì²â·ÖÇø×´¿ö£¬Í¨¹ýÇ°Ãæ»ñµÃµÄÓû§¶¨ÒåµÄãÐÖµºÍ df ÃüÁîµÄÊä³ö½øÐбȽϣ¬Èç¹û df ÏÔʾµÄij¸ö·ÖÇøµÄ¿Õ¼äÕ¼Óó¬¹ýÁËÓû§¶¨ÒåµÄã ......
http://blog.csdn.net/dinitial/archive/2009/02/22/3923559.aspx
Gdb+gdbserver+insight»·¾³µÄ´î½¨
1. ÏÂÔØgdbÔ´´úÂë http://ftp.gnu.org/gnu/gdb/
2. ÅäÖð²×°gdb+gdbser
$ tar jxvf gdb-6.6.tar.bz2
$ cd x/gdb
$ ./configure --target=arm-linux --prefix ......
4. Threads
To use the POSIX standard thread API (pthreads), link libpthread.so
to your program.
4.1. Thread Creation
Each thread in a process is identified by a thread ID,
pthread_t.
The pthread_self function returns the thread ID of the current
thread.
This thread IDs can be compared ......