Magellan Linux

  • Back to homepage
    • /[magellan-source]/trunk/mkinitrd-magellan/busybox/networking/udhcp/leases.c

    Diff of /trunk/mkinitrd-magellan/busybox/networking/udhcp/leases.c

    Parent Directory Parent Directory | Revision Log Revision Log | View Patch Patch

    revision 815 by niro, Sat Sep 1 22:45:15 2007 UTC revision 816 by niro, Fri Apr 24 18:33:46 2009 UTC
    # Line 8  Line 8 
    8  #include "dhcpd.h"  #include "dhcpd.h"
    9    
    10    
    11  uint8_t blank_chaddr[] = {[0 ... 15] = 0};  /* Find the oldest expired lease, NULL if there are no expired leases */
    12    static struct dhcpOfferedAddr *oldest_expired_lease(void)
    13    {
    14     struct dhcpOfferedAddr *oldest = NULL;
    15    // TODO: use monotonic_sec()
    16     unsigned long oldest_lease = time(0);
    17     unsigned i;
    18    
    19     for (i = 0; i < server_config.max_leases; i++)
    20     if (oldest_lease > leases[i].expires) {
    21     oldest_lease = leases[i].expires;
    22     oldest = &(leases[i]);
    23     }
    24     return oldest;
    25    }
    26    
    27    
    28  /* clear every lease out that chaddr OR yiaddr matches and is nonzero */  /* clear every lease out that chaddr OR yiaddr matches and is nonzero */
    29  void clear_lease(uint8_t *chaddr, uint32_t yiaddr)  static void clear_lease(const uint8_t *chaddr, uint32_t yiaddr)
    30  {  {
    31   unsigned int i, j;   unsigned i, j;
    32    
    33   for (j = 0; j < 16 && !chaddr[j]; j++);   for (j = 0; j < 16 && !chaddr[j]; j++)
    34     continue;
    35    
    36   for (i = 0; i < server_config.max_leases; i++)   for (i = 0; i < server_config.max_leases; i++)
    37   if ((j != 16 && !memcmp(leases[i].chaddr, chaddr, 16)) ||   if ((j != 16 && memcmp(leases[i].chaddr, chaddr, 16) == 0)
    38      (yiaddr && leases[i].yiaddr == yiaddr)) {   || (yiaddr && leases[i].yiaddr == yiaddr)
    39   memset(&(leases[i]), 0, sizeof(struct dhcpOfferedAddr));   ) {
    40     memset(&(leases[i]), 0, sizeof(leases[i]));
    41   }   }
    42  }  }
    43    
    44    
    45  /* add a lease into the table, clearing out any old ones */  /* add a lease into the table, clearing out any old ones */
    46  struct dhcpOfferedAddr *add_lease(uint8_t *chaddr, uint32_t yiaddr, unsigned long lease)  struct dhcpOfferedAddr* FAST_FUNC add_lease(const uint8_t *chaddr, uint32_t yiaddr, unsigned long lease)
    47  {  {
    48   struct dhcpOfferedAddr *oldest;   struct dhcpOfferedAddr *oldest;
    49    
    # Line 46  struct dhcpOfferedAddr *add_lease(uint8_ Line 63  struct dhcpOfferedAddr *add_lease(uint8_
    63    
    64    
    65  /* true if a lease has expired */  /* true if a lease has expired */
    66  int lease_expired(struct dhcpOfferedAddr *lease)  int FAST_FUNC lease_expired(struct dhcpOfferedAddr *lease)
    67  {  {
    68   return (lease->expires < (unsigned long) time(0));   return (lease->expires < (unsigned long) time(0));
    69  }  }
    70    
    71    
     /* Find the oldest expired lease, NULL if there are no expired leases */  
     struct dhcpOfferedAddr *oldest_expired_lease(void)  
     {  
      struct dhcpOfferedAddr *oldest = NULL;  
      unsigned long oldest_lease = time(0);  
      unsigned int i;  
       
       
      for (i = 0; i < server_config.max_leases; i++)  
      if (oldest_lease > leases[i].expires) {  
      oldest_lease = leases[i].expires;  
      oldest = &(leases[i]);  
      }  
      return oldest;  
       
     }  
       
       
    72  /* Find the first lease that matches chaddr, NULL if no match */  /* Find the first lease that matches chaddr, NULL if no match */
    73  struct dhcpOfferedAddr *find_lease_by_chaddr(uint8_t *chaddr)  struct dhcpOfferedAddr* FAST_FUNC find_lease_by_chaddr(const uint8_t *chaddr)
    74  {  {
    75   unsigned int i;   unsigned i;
    76    
    77   for (i = 0; i < server_config.max_leases; i++)   for (i = 0; i < server_config.max_leases; i++)
    78   if (!memcmp(leases[i].chaddr, chaddr, 16)) return &(leases[i]);   if (!memcmp(leases[i].chaddr, chaddr, 16))
    79     return &(leases[i]);
    80    
    81   return NULL;   return NULL;
    82  }  }
    83    
    84    
    85  /* Find the first lease that matches yiaddr, NULL is no match */  /* Find the first lease that matches yiaddr, NULL is no match */
    86  struct dhcpOfferedAddr *find_lease_by_yiaddr(uint32_t yiaddr)  struct dhcpOfferedAddr* FAST_FUNC find_lease_by_yiaddr(uint32_t yiaddr)
    87  {  {
    88   unsigned int i;   unsigned i;
    89    
    90   for (i = 0; i < server_config.max_leases; i++)   for (i = 0; i < server_config.max_leases; i++)
    91   if (leases[i].yiaddr == yiaddr) return &(leases[i]);   if (leases[i].yiaddr == yiaddr)
    92     return &(leases[i]);
    93    
    94   return NULL;   return NULL;
    95  }  }
    96    
    97    
    98  /* check is an IP is taken, if it is, add it to the lease table */  /* check is an IP is taken, if it is, add it to the lease table */
    99  static int check_ip(uint32_t addr)  static int nobody_responds_to_arp(uint32_t addr)
    100  {  {
    101     /* 16 zero bytes */
    102     static const uint8_t blank_chaddr[16] = { 0 };
    103     /* = { 0 } helps gcc to put it in rodata, not bss */
    104    
    105   struct in_addr temp;   struct in_addr temp;
    106     int r;
    107    
    108   if (arpping(addr, server_config.server, server_config.arp, server_config.interface) == 0) {   r = arpping(addr, server_config.server, server_config.arp, server_config.interface);
    109   temp.s_addr = addr;   if (r)
    110   bb_info_msg("%s belongs to someone, reserving it for %ld seconds",   return r;
    111   inet_ntoa(temp), server_config.conflict_time);  
    112   add_lease(blank_chaddr, addr, server_config.conflict_time);   temp.s_addr = addr;
    113   return 1;   bb_info_msg("%s belongs to someone, reserving it for %u seconds",
    114   } else return 0;   inet_ntoa(temp), (unsigned)server_config.conflict_time);
    115     add_lease(blank_chaddr, addr, server_config.conflict_time);
    116     return 0;
    117  }  }
    118    
    119    
    120  /* find an assignable address, it check_expired is true, we check all the expired leases as well.  /* find an assignable address, if check_expired is true, we check all the expired leases as well.
    121   * Maybe this should try expired leases by age... */   * Maybe this should try expired leases by age... */
    122  uint32_t find_address(int check_expired)  uint32_t FAST_FUNC find_address(int check_expired)
    123  {  {
    124   uint32_t addr, ret;   uint32_t addr, ret;
    125   struct dhcpOfferedAddr *lease = NULL;   struct dhcpOfferedAddr *lease = NULL;
    126    
    127   addr = ntohl(server_config.start); /* addr is in host order here */   addr = server_config.start_ip; /* addr is in host order here */
    128   for (;addr <= ntohl(server_config.end); addr++) {   for (; addr <= server_config.end_ip; addr++) {
       
    129   /* ie, 192.168.55.0 */   /* ie, 192.168.55.0 */
    130   if (!(addr & 0xFF)) continue;   if (!(addr & 0xFF))
    131     continue;
    132   /* ie, 192.168.55.255 */   /* ie, 192.168.55.255 */
    133   if ((addr & 0xFF) == 0xFF) continue;   if ((addr & 0xFF) == 0xFF)
    134     continue;
    135   /* Only do if it isn't an assigned as a static lease */   /* Only do if it isn't assigned as a static lease */
    136   if (!reservedIp(server_config.static_leases, htonl(addr))) {   ret = htonl(addr);
    137     if (!reservedIp(server_config.static_leases, ret)) {
    138   /* lease is not taken */   /* lease is not taken */
      ret = htonl(addr);  
    139   lease = find_lease_by_yiaddr(ret);   lease = find_lease_by_yiaddr(ret);
       
    140   /* no lease or it expired and we are checking for expired leases */   /* no lease or it expired and we are checking for expired leases */
    141   if ( (!lease || (check_expired && lease_expired(lease)))   if ((!lease || (check_expired && lease_expired(lease)))
    142   && /* and it isn't on the network */ !check_ip(ret)   && nobody_responds_to_arp(ret) /* it isn't used on the network */
    143   ) {   ) {
    144   return ret;   return ret;
      break;  
    145   }   }
    146   }   }
    147   }   }
    Legend:
    Removed from v.815  
    changed lines
      Added in v.816