From 73121c3c8c28d299280a2f1360e038e93f0b254f Mon Sep 17 00:00:00 2001 From: Denis Vlasenko Date: Sun, 1 Feb 2009 00:40:45 +0000 Subject: dhcpd,dumpleases: write and use 64-bit current time in lease file. without it, determination of remaining lease time is unreliable. Yes, it's costly in code size, but without it, dumpleases output is misleading! function old new delta read_leases 143 282 +139 dumpleases_main 447 572 +125 write_leases 193 233 +40 hton64 29 58 +29 ------------------------------------------------------------------------------ (add/remove: 0/0 grow/shrink: 4/0 up/down: 333/0) Total: 333 bytes --- networking/udhcp/dumpleases.c | 27 ++++++++++++++++++++++----- 1 file changed, 22 insertions(+), 5 deletions(-) (limited to 'networking/udhcp/dumpleases.c') diff --git a/networking/udhcp/dumpleases.c b/networking/udhcp/dumpleases.c index 2d16ec160..c0d515d28 100644 --- a/networking/udhcp/dumpleases.c +++ b/networking/udhcp/dumpleases.c @@ -6,14 +6,24 @@ #include "common.h" #include "dhcpd.h" +#if BB_LITTLE_ENDIAN +static inline uint64_t hton64(uint64_t v) +{ + return (((uint64_t)htonl(v)) << 32) | htonl(v >> 32); +} +#else +#define hton64(v) (v) +#endif +#define ntoh64(v) hton64(v) + + int dumpleases_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; int dumpleases_main(int argc UNUSED_PARAM, char **argv) { int fd; int i; unsigned opt; - leasetime_t expires; - leasetime_t curr; + int64_t written_at, curr, expires_abs; const char *file = LEASES_FILE; struct dhcpOfferedAddr lease; struct in_addr addr; @@ -40,7 +50,13 @@ int dumpleases_main(int argc UNUSED_PARAM, char **argv) printf("Mac Address IP-Address Expires %s\n", (opt & OPT_a) ? "at" : "in"); /* "00:00:00:00:00:00 255.255.255.255 Wed Jun 30 21:49:08 1993" */ + if (full_read(fd, &written_at, sizeof(written_at)) != sizeof(written_at)) + return 0; + written_at = ntoh64(written_at); curr = time(NULL); + if (curr < written_at) + written_at = curr; /* lease file from future! :) */ + while (full_read(fd, &lease, sizeof(lease)) == sizeof(lease)) { const char *fmt = ":%02x" + 1; for (i = 0; i < 6; i++) { @@ -49,13 +65,14 @@ int dumpleases_main(int argc UNUSED_PARAM, char **argv) } addr.s_addr = lease.yiaddr; printf(" %-15s ", inet_ntoa(addr)); - if (lease.expires == 0) { + expires_abs = ntohl(lease.expires) + written_at; + if (expires_abs <= curr) { puts("expired"); continue; } - expires = ntohl(lease.expires); if (!(opt & OPT_a)) { /* no -a */ unsigned d, h, m; + unsigned expires = expires_abs - curr; d = expires / (24*60*60); expires %= (24*60*60); h = expires / (60*60); expires %= (60*60); m = expires / 60; expires %= 60; @@ -63,7 +80,7 @@ int dumpleases_main(int argc UNUSED_PARAM, char **argv) printf("%u days ", d); printf("%02u:%02u:%02u\n", h, m, (unsigned)expires); } else { /* -a */ - time_t t = expires + curr; + time_t t = expires_abs; fputs(ctime(&t), stdout); } } -- cgit v1.2.3