1 /* 2 * $Id: ip_util.c,v 1.1 2004/11/14 07:26:26 paulus Exp $ 3 * 4 * Copyright (C) 1995,1996,1997 Lars Fenneberg 5 * 6 * Copyright 1992 Livingston Enterprises, Inc. 7 * 8 * Copyright 1992,1993, 1994,1995 The Regents of the University of Michigan 9 * and Merit Network, Inc. All Rights Reserved 10 * 11 * See the file COPYRIGHT for the respective terms and conditions. 12 * If the file is missing contact me at lf (at) elemental.net 13 * and I'll send you a copy. 14 * 15 */ 16 17 #include <includes.h> 18 #include <radiusclient.h> 19 20 /* 21 * Function: rc_get_ipaddr 22 * 23 * Purpose: return an IP address in host long notation from a host 24 * name or address in dot notation. 25 * 26 * Returns: 0 on failure 27 */ 28 29 UINT4 rc_get_ipaddr (char *host) 30 { 31 struct hostent *hp; 32 33 if (rc_good_ipaddr (host) == 0) 34 { 35 return ntohl(inet_addr (host)); 36 } 37 else if ((hp = gethostbyname (host)) == (struct hostent *) NULL) 38 { 39 error("rc_get_ipaddr: couldn't resolve hostname: %s", host); 40 return ((UINT4) 0); 41 } 42 return ntohl((*(UINT4 *) hp->h_addr)); 43 } 44 45 /* 46 * Function: rc_good_ipaddr 47 * 48 * Purpose: check for valid IP address in standard dot notation. 49 * 50 * Returns: 0 on success, -1 when failure 51 * 52 */ 53 54 int rc_good_ipaddr (char *addr) 55 { 56 int dot_count; 57 int digit_count; 58 59 if (addr == NULL) 60 return (-1); 61 62 dot_count = 0; 63 digit_count = 0; 64 while (*addr != '\0' && *addr != ' ') 65 { 66 if (*addr == '.') 67 { 68 dot_count++; 69 digit_count = 0; 70 } 71 else if (!isdigit (*addr)) 72 { 73 dot_count = 5; 74 } 75 else 76 { 77 digit_count++; 78 if (digit_count > 3) 79 { 80 dot_count = 5; 81 } 82 } 83 addr++; 84 } 85 if (dot_count != 3) 86 { 87 return (-1); 88 } 89 else 90 { 91 return (0); 92 } 93 } 94 95 /* 96 * Function: rc_ip_hostname 97 * 98 * Purpose: Return a printable host name (or IP address in dot notation) 99 * for the supplied IP address. 100 * 101 */ 102 103 const char *rc_ip_hostname (UINT4 h_ipaddr) 104 { 105 struct hostent *hp; 106 UINT4 n_ipaddr = htonl (h_ipaddr); 107 108 if ((hp = gethostbyaddr ((char *) &n_ipaddr, sizeof (struct in_addr), 109 AF_INET)) == NULL) { 110 error("rc_ip_hostname: couldn't look up host by addr: %08lX", h_ipaddr); 111 } 112 113 return ((hp==NULL)?"unknown":hp->h_name); 114 } 115 116 /* 117 * Function: rc_own_ipaddress 118 * 119 * Purpose: get the IP address of this host in host order 120 * 121 * Returns: IP address on success, 0 on failure 122 * 123 */ 124 125 UINT4 rc_own_ipaddress(void) 126 { 127 static UINT4 this_host_ipaddr = 0; 128 129 if (!this_host_ipaddr) { 130 if ((this_host_ipaddr = rc_get_ipaddr (hostname)) == 0) { 131 error("rc_own_ipaddress: couldn't get own IP address"); 132 return 0; 133 } 134 } 135 136 return this_host_ipaddr; 137 } 138