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תÌù×Ô£ºhttp://alexanderlaw.blog.hexun.com/8968782_d.html
Èý¡¢ipt_table±íµÄ×¢²á
 
init£¨£©º¯Êý³õʼ»¯Ê±µ÷ÓÃÁËipt_register_tableº¯Êý½øÐбíµÄ×¢²á
 
3.1  ip_tables.c ±íµÄ×¢²á ipt_register_table
int ipt_register_table(struct ipt_table *table)
{
       int ret;
       struct ipt_table_info *newinfo;
       static struct ipt_table_info bootstrap
              = { 0, 0, 0, { 0 }, { 0 }, { } };
 
/*ºêMOD_INC_USE_COUNTÓÃÓÚÄ£¿é¼ÆÊýÆ÷ÀÛ¼Ó£¬Ö÷ÒªÊÇΪÁË·Àֹģ¿éÒ쳣ɾ³ý£¬¶ÔÓ¦µÄºêMOD_DEC_USE_COUNT¾ÍÊÇÀÛ¼õÁË*/
       MOD_INC_USE_COUNT;  
 
/*Ϊÿ¸öCPU·ÖÅä¹æÔò¿Õ¼ä*/
       newinfo = vmalloc(sizeof(struct ipt_table_info)
                       + SMP_ALIGN(table->table->size) * smp_num_cpus);
       if (!newinfo) {
              ret = -ENOMEM;
              MOD_DEC_USE_COUNT;
              return ret;
       }
 
/*½«¹æÔòÏ±´µ½Ð±íÏîµÄµÚÒ»¸öcpu¿Õ¼äÀïÃæ*/
       memcpy(newinfo->entries, table->table->entries, table->table->size);
 
/*translate_tableº¯Êý½«newinfo±íʾµÄtableµÄ¸÷¸ö¹æÔò½øÐб߽ç¼ì²é£¬È»ºó¶ÔÓÚnewinfoËùÖ¸µÄipt_talbe_info½á¹¹ÖеÄhook_entriesºÍunderflows¸³ÓèÕýÈ·µÄÖµ£¬×îºó½«±íÏîÏòÆäËûcpu¿½±´*/
       ret = translate_table(table->name, table->valid_hooks,
                 &