1 /* vi: set sw=4 ts=4: */
2 /*
3 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
4 */
5 //applet:IF_DUMPLEASES(APPLET_NOEXEC(dumpleases, dumpleases, BB_DIR_USR_BIN, BB_SUID_DROP, dumpleases))
6
7 //kbuild:lib-$(CONFIG_DUMPLEASES) += dumpleases.o
8
9 //usage:#define dumpleases_trivial_usage
10 //usage: "[-r|-a] [-d] [-f LEASEFILE]"
11 //usage:#define dumpleases_full_usage "\n\n"
12 //usage: "Display DHCP leases granted by udhcpd\n"
13 //usage: "\n -f FILE Lease file"
14 //usage: "\n -r Show remaining time"
15 //usage: "\n -a Show expiration time"
16 //usage: "\n -d Show time in seconds"
17
18 #include "common.h"
19 #include "dhcpd.h"
20 #include "unicode.h"
21
22 int dumpleases_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
dumpleases_main(int argc UNUSED_PARAM,char ** argv)23 int dumpleases_main(int argc UNUSED_PARAM, char **argv)
24 {
25 int fd;
26 int i;
27 unsigned opt;
28 int64_t written_at, curr;
29 const char *file = LEASES_FILE;
30 struct dyn_lease lease;
31
32 enum {
33 OPT_a = 0x1, // -a
34 OPT_r = 0x2, // -r
35 OPT_f = 0x4, // -f
36 OPT_d = 0x8, // -d
37 };
38 #if ENABLE_LONG_OPTS
39 static const char dumpleases_longopts[] ALIGN1 =
40 "absolute\0" No_argument "a"
41 "remaining\0" No_argument "r"
42 "file\0" Required_argument "f"
43 "decimal\0" No_argument "d"
44 ;
45
46 #endif
47 init_unicode();
48
49 opt = getopt32long(argv, "^"
50 "arf:d"
51 "\0" "=0:a--r:r--a",
52 dumpleases_longopts,
53 &file
54 );
55
56 fd = xopen(file, O_RDONLY);
57
58 /* "123456789 123456789 123456789 123456789 123456789 123456789 123456789 123456789 */
59 /* "00:00:00:00:00:00 255.255.255.255 ABCDEFGHIJKLMNOPQRS Wed Jun 30 21:49:08 1993" */
60 printf("Mac %-14s" "IP %-13s" "Host %-15s" "Expires %s\n",
61 "Address", "Address", "Name",
62 (opt & OPT_a) ? "at" : "in"
63 );
64
65 xread(fd, &written_at, sizeof(written_at));
66 written_at = SWAP_BE64(written_at);
67 curr = time(NULL);
68 if (curr < written_at)
69 written_at = curr; /* lease file from future! :) */
70
71 while (full_read(fd, &lease, sizeof(lease)) == sizeof(lease)) {
72 struct in_addr addr;
73 int64_t expires_abs;
74
75 const char *fmt = ":%02x" + 1;
76 for (i = 0; i < 6; i++) {
77 printf(fmt, lease.lease_mac[i]);
78 fmt = ":%02x";
79 }
80 addr.s_addr = lease.lease_nip;
81 #if ENABLE_UNICODE_SUPPORT
82 {
83 char *uni_name = unicode_conv_to_printable_fixedwidth(/*NULL,*/ lease.hostname, 19);
84 printf(" %-16s%s ", inet_ntoa(addr), uni_name);
85 free(uni_name);
86 }
87 #else
88 /* actually, 15+1 and 19+1, +1 is a space between columns */
89 /* lease.hostname is char[20] and is always NUL terminated */
90 printf(" %-16s%-20s", inet_ntoa(addr), lease.hostname);
91 #endif
92 expires_abs = ntohl(lease.expires) + written_at;
93 if (expires_abs <= curr) {
94 puts("expired");
95 continue;
96 }
97 if (opt & OPT_d) {
98 /* -d: decimal time */
99 if (!(opt & OPT_a))
100 expires_abs -= curr;
101 printf("%llu\n", (unsigned long long) expires_abs);
102 continue;
103 }
104 if (!(opt & OPT_a)) { /* no -a */
105 unsigned d, h, m;
106 unsigned expires = expires_abs - curr;
107 d = expires / (24*60*60); expires %= (24*60*60);
108 h = expires / (60*60); expires %= (60*60);
109 m = expires / 60; expires %= 60;
110 if (d)
111 printf("%u days ", d);
112 printf("%02u:%02u:%02u\n", h, m, (unsigned)expires);
113 } else { /* -a */
114 time_t t = expires_abs;
115 fputs_stdout(ctime(&t));
116 }
117 }
118 /* close(fd); */
119
120 return 0;
121 }
122