Contents of /tags/mkinitrd-6_1_0/busybox/networking/ipcalc.c
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Fri Apr 24 19:09:57 2009 UTC (15 years, 5 months ago) by niro
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File size: 4410 byte(s)
Fri Apr 24 19:09:57 2009 UTC (15 years, 5 months ago) by niro
File MIME type: text/plain
File size: 4410 byte(s)
tagged 'mkinitrd-6_1_0'
1 | /* vi: set sw=4 ts=4: */ |
2 | /* |
3 | * Mini ipcalc implementation for busybox |
4 | * |
5 | * By Jordan Crouse <jordan@cosmicpenguin.net> |
6 | * Stephan Linz <linz@li-pro.net> |
7 | * |
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 |
11 | * |
12 | * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. |
13 | */ |
14 | |
15 | #include <sys/socket.h> |
16 | #include <arpa/inet.h> |
17 | |
18 | #include "libbb.h" |
19 | |
20 | #define CLASS_A_NETMASK ntohl(0xFF000000) |
21 | #define CLASS_B_NETMASK ntohl(0xFFFF0000) |
22 | #define CLASS_C_NETMASK ntohl(0xFFFFFF00) |
23 | |
24 | static unsigned long get_netmask(unsigned long ipaddr) |
25 | { |
26 | ipaddr = htonl(ipaddr); |
27 | |
28 | if ((ipaddr & 0xC0000000) == 0xC0000000) |
29 | return CLASS_C_NETMASK; |
30 | else if ((ipaddr & 0x80000000) == 0x80000000) |
31 | return CLASS_B_NETMASK; |
32 | else if ((ipaddr & 0x80000000) == 0) |
33 | return CLASS_A_NETMASK; |
34 | else |
35 | return 0; |
36 | } |
37 | |
38 | #if ENABLE_FEATURE_IPCALC_FANCY |
39 | static int get_prefix(unsigned long netmask) |
40 | { |
41 | unsigned long msk = 0x80000000; |
42 | int ret = 0; |
43 | |
44 | netmask = htonl(netmask); |
45 | while (msk) { |
46 | if (netmask & msk) |
47 | ret++; |
48 | msk >>= 1; |
49 | } |
50 | return ret; |
51 | } |
52 | #else |
53 | int get_prefix(unsigned long netmask); |
54 | #endif |
55 | |
56 | |
57 | #define NETMASK 0x01 |
58 | #define BROADCAST 0x02 |
59 | #define NETWORK 0x04 |
60 | #define NETPREFIX 0x08 |
61 | #define HOSTNAME 0x10 |
62 | #define SILENT 0x20 |
63 | |
64 | #if ENABLE_FEATURE_IPCALC_LONG_OPTIONS |
65 | static const char ipcalc_longopts[] ALIGN1 = |
66 | "netmask\0" No_argument "m" |
67 | "broadcast\0" No_argument "b" |
68 | "network\0" No_argument "n" |
69 | # if ENABLE_FEATURE_IPCALC_FANCY |
70 | "prefix\0" No_argument "p" |
71 | "hostname\0" No_argument "h" |
72 | "silent\0" No_argument "s" |
73 | # endif |
74 | ; |
75 | #endif |
76 | |
77 | int ipcalc_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
78 | int ipcalc_main(int argc, char **argv) |
79 | { |
80 | unsigned opt; |
81 | int have_netmask = 0; |
82 | in_addr_t netmask, broadcast, network, ipaddr; |
83 | struct in_addr a; |
84 | char *ipstr; |
85 | |
86 | #if ENABLE_FEATURE_IPCALC_LONG_OPTIONS |
87 | applet_long_options = ipcalc_longopts; |
88 | #endif |
89 | opt = getopt32(argv, "mbn" USE_FEATURE_IPCALC_FANCY("phs")); |
90 | argc -= optind; |
91 | argv += optind; |
92 | if (opt & (BROADCAST | NETWORK | NETPREFIX)) { |
93 | if (argc > 2 || argc <= 0) |
94 | bb_show_usage(); |
95 | } else { |
96 | if (argc != 1) |
97 | bb_show_usage(); |
98 | } |
99 | if (opt & SILENT) |
100 | logmode = LOGMODE_NONE; /* Suppress error_msg() output */ |
101 | |
102 | ipstr = argv[0]; |
103 | if (ENABLE_FEATURE_IPCALC_FANCY) { |
104 | unsigned long netprefix = 0; |
105 | char *prefixstr; |
106 | |
107 | prefixstr = ipstr; |
108 | |
109 | while (*prefixstr) { |
110 | if (*prefixstr == '/') { |
111 | *prefixstr = (char)0; |
112 | prefixstr++; |
113 | if (*prefixstr) { |
114 | unsigned msk; |
115 | netprefix = xatoul_range(prefixstr, 0, 32); |
116 | netmask = 0; |
117 | msk = 0x80000000; |
118 | while (netprefix > 0) { |
119 | netmask |= msk; |
120 | msk >>= 1; |
121 | netprefix--; |
122 | } |
123 | netmask = htonl(netmask); |
124 | /* Even if it was 0, we will signify that we have a netmask. This allows */ |
125 | /* for specification of default routes, etc which have a 0 netmask/prefix */ |
126 | have_netmask = 1; |
127 | } |
128 | break; |
129 | } |
130 | prefixstr++; |
131 | } |
132 | } |
133 | ipaddr = inet_aton(ipstr, &a); |
134 | |
135 | if (ipaddr == 0) { |
136 | bb_error_msg_and_die("bad IP address: %s", argv[0]); |
137 | } |
138 | ipaddr = a.s_addr; |
139 | |
140 | if (argc == 2) { |
141 | if (ENABLE_FEATURE_IPCALC_FANCY && have_netmask) { |
142 | bb_error_msg_and_die("use prefix or netmask, not both"); |
143 | } |
144 | |
145 | netmask = inet_aton(argv[1], &a); |
146 | if (netmask == 0) { |
147 | bb_error_msg_and_die("bad netmask: %s", argv[1]); |
148 | } |
149 | netmask = a.s_addr; |
150 | } else { |
151 | |
152 | /* JHC - If the netmask wasn't provided then calculate it */ |
153 | if (!ENABLE_FEATURE_IPCALC_FANCY || !have_netmask) |
154 | netmask = get_netmask(ipaddr); |
155 | } |
156 | |
157 | if (opt & NETMASK) { |
158 | printf("NETMASK=%s\n", inet_ntoa((*(struct in_addr *) &netmask))); |
159 | } |
160 | |
161 | if (opt & BROADCAST) { |
162 | broadcast = (ipaddr & netmask) | ~netmask; |
163 | printf("BROADCAST=%s\n", inet_ntoa((*(struct in_addr *) &broadcast))); |
164 | } |
165 | |
166 | if (opt & NETWORK) { |
167 | network = ipaddr & netmask; |
168 | printf("NETWORK=%s\n", inet_ntoa((*(struct in_addr *) &network))); |
169 | } |
170 | |
171 | if (ENABLE_FEATURE_IPCALC_FANCY) { |
172 | if (opt & NETPREFIX) { |
173 | printf("PREFIX=%i\n", get_prefix(netmask)); |
174 | } |
175 | |
176 | if (opt & HOSTNAME) { |
177 | struct hostent *hostinfo; |
178 | |
179 | hostinfo = gethostbyaddr((char *) &ipaddr, sizeof(ipaddr), AF_INET); |
180 | if (!hostinfo) { |
181 | bb_herror_msg_and_die("cannot find hostname for %s", argv[0]); |
182 | } |
183 | str_tolower(hostinfo->h_name); |
184 | |
185 | printf("HOSTNAME=%s\n", hostinfo->h_name); |
186 | } |
187 | } |
188 | |
189 | return EXIT_SUCCESS; |
190 | } |