usr.sbin/bootp/common/lookup.c

   1 /*      $NetBSD: lookup.c,v 1.5 2002/07/14 00:26:17 wiz Exp $   */
   2
   3 #include <sys/cdefs.h>
   4 #ifndef lint
   5 __RCSID("$NetBSD: lookup.c,v 1.5 2002/07/14 00:26:17 wiz Exp $");
   6 #endif
   7
   8 /*
   9  * lookup.c - Lookup IP address, HW address, netmask
  10  */
  11
  12 #include <sys/types.h>
  13 #include <sys/socket.h>
  14
  15 #include <net/if.h>
  16 #include <netinet/in.h>
  17
  18 #ifdef  ETC_ETHERS
  19 #include <net/if_ether.h>
  20 #endif
  21
  22 #include <netdb.h>
  23 #include <syslog.h>
  24 #include <strings.h>
  25
  26 #include "bootp.h"
  27 #include "lookup.h"
  28 #include "report.h"
  29
  30 /*
  31  * Lookup an Ethernet address and return it.
  32  * Return NULL if addr not found.
  33  */
  34 u_char *
  35 lookup_hwa(char *hostname, int htype)
  36 {
  37         switch (htype) {
  38
  39                 /* XXX - How is this done on other systems? -gwr */
  40 #ifdef  ETC_ETHERS
  41         case HTYPE_ETHERNET:
  42         case HTYPE_IEEE802:
  43                 {
  44                         static struct ether_addr ea;
  45                         /* This does a lookup in /etc/ethers */
  46                         if (ether_hostton(hostname, &ea)) {
  47                                 report(LOG_ERR, "no HW addr for host \"%s\"",
  48                                            hostname);
  49                                 return (u_char *) 0;
  50                         }
  51                         return (u_char *) & ea;
  52                 }
  53 #endif /* ETC_ETHERS */
  54
  55         default:
  56                 report(LOG_ERR, "no lookup for HW addr type %d", htype);
  57         }                                                       /* switch */
  58
  59         /* If the system can't do it, just return an error. */
  60         return (u_char *) 0;
  61 }
  62
  63
  64 /*
  65  * Lookup an IP address.
  66  * Return non-zero on failure.
  67  */
  68 int
  69 lookup_ipa(char *hostname, u_int32 *result)
  70 {
  71         struct hostent *hp;
  72         hp = gethostbyname(hostname);
  73         if (!hp)
  74                 return -1;
  75         bcopy(hp->h_addr, result, sizeof(*result));
  76         return 0;
  77 }
  78
  79
  80 /*
  81  * Lookup a netmask
  82  * Return non-zero on failure.
  83  *
  84  * XXX - This is OK as a default, but to really make this automatic,
  85  * we would need to get the subnet mask from the ether interface.
  86  * If this is wrong, specify the correct value in the bootptab.
  87  *
  88  * Both inputs are in network order.
  89  */
  90 int
  91 lookup_netmask(u_int32 addr, u_int32 *result)
  92 {
  93         int32 m, a;
  94
  95         a = ntohl(addr);
  96         m = 0;
  97
  98         if (IN_CLASSA(a))
  99                 m = IN_CLASSA_NET;
 100
 101         if (IN_CLASSB(a))
 102                 m = IN_CLASSB_NET;
 103
 104         if (IN_CLASSC(a))
 105                 m = IN_CLASSC_NET;
 106
 107         if (!m)
 108                 return -1;
 109         *result = htonl(m);
 110         return 0;
 111 }
 112
 113 /*
 114  * Local Variables:
 115  * tab-width: 4
 116  * c-indent-level: 4
 117  * c-argdecl-indent: 4
 118  * c-continued-statement-offset: 4
 119  * c-continued-brace-offset: -4
 120  * c-label-offset: -4
 121  * c-brace-offset: 0
 122  * End:
 123  */