lib/libatm/ip_addr.c

   1 /*
   2  *
   3  * ===================================
   4  * HARP  |  Host ATM Research Platform
   5  * ===================================
   6  *
   7  *
   8  * This Host ATM Research Platform ("HARP") file (the "Software") is
   9  * made available by Network Computing Services, Inc. ("NetworkCS")
  10  * "AS IS".  NetworkCS does not provide maintenance, improvements or
  11  * support of any kind.
  12  *
  13  * NETWORKCS MAKES NO WARRANTIES OR REPRESENTATIONS, EXPRESS OR IMPLIED,
  14  * INCLUDING, BUT NOT LIMITED TO, IMPLIED WARRANTIES OF MERCHANTABILITY
  15  * AND FITNESS FOR A PARTICULAR PURPOSE, AS TO ANY ELEMENT OF THE
  16  * SOFTWARE OR ANY SUPPORT PROVIDED IN CONNECTION WITH THIS SOFTWARE.
  17  * In no event shall NetworkCS be responsible for any damages, including
  18  * but not limited to consequential damages, arising from or relating to
  19  * any use of the Software or related support.
  20  *
  21  * Copyright 1994-1998 Network Computing Services, Inc.
  22  *
  23  * Copies of this Software may be made, however, the above copyright
  24  * notice must be reproduced on all copies.
  25  *
  26  *      @(#) $FreeBSD: src/lib/libatm/ip_addr.c,v 1.3.2.1 2001/09/28 16:52:10 dillon Exp $
  27  *      @(#) $DragonFly: src/lib/libatm/ip_addr.c,v 1.5 2008/09/30 16:57:04 swildner Exp $
  28  *
  29  */
  30
  31 #include <sys/cdefs.h>
  32
  33 /*
  34  * User Space Library Functions
  35  * ----------------------------
  36  *
  37  * IP address utilities
  38  *
  39  */
  40
  41 #include <sys/types.h>
  42 #include <sys/param.h>
  43 #include <sys/socket.h>
  44 #include <net/if.h>
  45 #include <netinet/in.h>
  46 #include <arpa/inet.h>
  47 #include <netatm/port.h>
  48 #include <netatm/atm.h>
  49 #include <netatm/atm_if.h>
  50 #include <netatm/atm_sap.h>
  51 #include <netatm/atm_sys.h>
  52 #include <netatm/atm_ioctl.h>
  53
  54 #include <netdb.h>
  55 #include <stdio.h>
  56 #include <string.h>
  57
  58 #include "libatm.h"
  59
  60 /*
  61  * Get IP address
  62  *
  63  * Return an IP address in a socket address structure, given a character
  64  * string with a domain name or a dotted decimal number.
  65  *
  66  * Arguments:
  67  *      p       pointer to a host name or IP address
  68  *
  69  * Returns:
  70  *      null                    error was encountered
  71  *      struct sockaddr_in *    a pointer to a socket address with the
  72  *                              requested IP address
  73  *
  74  */
  75 struct sockaddr_in *
  76 get_ip_addr(char *p)
  77 {
  78         struct hostent                  *ip_host;
  79         static struct sockaddr_in       sin;
  80
  81         /*
  82          * Get IP address of specified host name
  83          */
  84         UM_ZERO(&sin, sizeof(sin));
  85         sin.sin_family = AF_INET;
  86         if (p[0] >= '0' && p[0] <= '9') {
  87                 /*
  88                  * IP address is in dotted decimal format
  89                  */
  90                 if ((sin.sin_addr.s_addr = inet_addr(p)) == -1) {
  91                         return(NULL);
  92                 }
  93         } else {
  94                 /*
  95                  * Host name is in domain name system format
  96                  */
  97                 ip_host = gethostbyname(p);
  98                 if (!ip_host ||
  99                                 ip_host->h_addrtype != AF_INET) {
 100                         return(NULL);
 101                 }
 102                 sin.sin_addr.s_addr = *(u_long *)ip_host->h_addr_list[0];
 103         }
 104         return(&sin);
 105 }
 106
 107
 108 /*
 109  * Format an IP address
 110  *
 111  * Return a text-formatted string with an IP address and domain name
 112  * given a sockaddr_in with an IP address.
 113  *
 114  * Arguments:
 115  *      p       pointer to sockaddr_in with an IP address
 116  *
 117  * Returns:
 118  *      char *  pointer to a text-formatted string
 119  *
 120  */
 121 char *
 122 format_ip_addr(struct in_addr *addr)
 123 {
 124         static char     host_name[MAXHOSTNAMELEN + 18];
 125         char            *ip_num;
 126         struct hostent  *ip_host;
 127
 128         /*
 129          * Initialize
 130          */
 131         UM_ZERO(host_name, sizeof(host_name));
 132
 133         /*
 134          * Check for a zero address
 135          */
 136         if (!addr || addr->s_addr == 0) {
 137                 return("-");
 138         }
 139
 140         /*
 141          * Get address in dotted decimal format
 142          */
 143         ip_num = inet_ntoa(*addr);
 144
 145         /*
 146          * Look up name in DNS
 147          */
 148         ip_host = gethostbyaddr(addr, sizeof(addr), AF_INET);
 149         if (ip_host && ip_host->h_name &&
 150                         strlen(ip_host->h_name)) {
 151                 /*
 152                  * Return host name followed by dotted decimal address
 153                  */
 154                 snprintf(host_name, sizeof(host_name), "%s (%s)",
 155                         ip_host->h_name, ip_num);
 156                 return (host_name);
 157         } else {
 158                 /*
 159                  * No host name -- just return dotted decimal address
 160                  */
 161                 return(ip_num);
 162         }
 163 }