1 /* vi: set sw=4 ts=4: */
3 * Mini ipcalc implementation for busybox
5 * By Jordan Crouse <jordan@cosmicpenguin.net>
6 * Stephan Linz <linz@li-pro.net>
8 * This is a complete reimplementation of the ipcalc program
9 * from Red Hat. I didn't look at their source code, but there
10 * is no denying that this is a loving reimplementation
12 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
18 #include <sys/socket.h>
19 #include <arpa/inet.h>
21 #define IPCALC_MSG(CMD,ALTCMD) if (mode & SILENT) {ALTCMD;} else {CMD;}
23 #define CLASS_A_NETMASK ntohl(0xFF000000)
24 #define CLASS_B_NETMASK ntohl(0xFFFF0000)
25 #define CLASS_C_NETMASK ntohl(0xFFFFFF00)
27 static unsigned long get_netmask(unsigned long ipaddr)
29 ipaddr = htonl(ipaddr);
31 if ((ipaddr & 0xC0000000) == 0xC0000000)
32 return CLASS_C_NETMASK;
33 else if ((ipaddr & 0x80000000) == 0x80000000)
34 return CLASS_B_NETMASK;
35 else if ((ipaddr & 0x80000000) == 0)
36 return CLASS_A_NETMASK;
41 #ifdef CONFIG_FEATURE_IPCALC_FANCY
42 static int get_prefix(unsigned long netmask)
44 unsigned long msk = 0x80000000;
47 netmask = htonl(netmask);
56 int get_prefix(unsigned long netmask);
60 #define BROADCAST 0x02
62 #define NETPREFIX 0x08
66 #if ENABLE_FEATURE_IPCALC_LONG_OPTIONS
67 static const struct option long_options[] = {
68 {"netmask", no_argument, NULL, 'm'},
69 {"broadcast", no_argument, NULL, 'b'},
70 {"network", no_argument, NULL, 'n'},
71 #ifdef CONFIG_FEATURE_IPCALC_FANCY
72 {"prefix", no_argument, NULL, 'p'},
73 {"hostname", no_argument, NULL, 'h'},
74 {"silent", no_argument, NULL, 's'},
79 #define long_options 0
84 int ipcalc_main(int argc, char **argv)
88 in_addr_t netmask, broadcast, network, ipaddr;
92 if (ENABLE_FEATURE_IPCALC_LONG_OPTIONS)
93 bb_applet_long_options = long_options;
95 mode = bb_getopt_ulflags(argc, argv, "mbn" USE_FEATURE_IPCALC_FANCY("phs"));
99 if (mode & (BROADCAST | NETWORK | NETPREFIX)) {
100 if (argc > 2 || argc <= 0)
108 if (ENABLE_FEATURE_IPCALC_FANCY) {
109 unsigned long netprefix = 0;
115 if (*prefixstr == '/') {
116 *prefixstr = (char)0;
121 if (safe_strtoul(prefixstr, &netprefix) || netprefix > 32) {
122 IPCALC_MSG(bb_error_msg_and_die("bad IP prefix: %s", prefixstr),
127 while (netprefix > 0) {
132 netmask = htonl(netmask);
133 /* Even if it was 0, we will signify that we have a netmask. This allows */
134 /* for specification of default routes, etc which have a 0 netmask/prefix */
142 ipaddr = inet_aton(ipstr, &a);
145 IPCALC_MSG(bb_error_msg_and_die("bad IP address: %s", argv[0]),
151 if (ENABLE_FEATURE_IPCALC_FANCY && have_netmask) {
152 IPCALC_MSG(bb_error_msg_and_die("Use prefix or netmask, not both"),
156 netmask = inet_aton(argv[1], &a);
158 IPCALC_MSG(bb_error_msg_and_die("bad netmask: %s", argv[1]),
164 /* JHC - If the netmask wasn't provided then calculate it */
165 if (!ENABLE_FEATURE_IPCALC_FANCY || !have_netmask)
166 netmask = get_netmask(ipaddr);
169 if (mode & NETMASK) {
170 printf("NETMASK=%s\n", inet_ntoa((*(struct in_addr *) &netmask)));
173 if (mode & BROADCAST) {
174 broadcast = (ipaddr & netmask) | ~netmask;
175 printf("BROADCAST=%s\n", inet_ntoa((*(struct in_addr *) &broadcast)));
178 if (mode & NETWORK) {
179 network = ipaddr & netmask;
180 printf("NETWORK=%s\n", inet_ntoa((*(struct in_addr *) &network)));
183 if (ENABLE_FEATURE_IPCALC_FANCY) {
184 if (mode & NETPREFIX) {
185 printf("PREFIX=%i\n", get_prefix(netmask));
188 if (mode & HOSTNAME) {
189 struct hostent *hostinfo;
192 hostinfo = gethostbyaddr((char *) &ipaddr, sizeof(ipaddr), AF_INET);
194 IPCALC_MSG(bb_herror_msg_and_die(
195 "cannot find hostname for %s", argv[0]),);
198 for (x = 0; hostinfo->h_name[x]; x++) {
199 hostinfo->h_name[x] = tolower(hostinfo->h_name[x]);
202 printf("HOSTNAME=%s\n", hostinfo->h_name);