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-rw-r--r--plugins/check_ntp.c355
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diff --git a/plugins/check_ntp.c b/plugins/check_ntp.c
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+/******************************************************************************
+ check_ntp.c: utility to check ntp servers independant of any commandline
+ programs or external libraries.
+ original author: sean finney <seanius@seanius.net>
+ ******************************************************************************
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ $Id$
+
+*****************************************************************************/
+
+const char *progname = "check_ntp";
+const char *revision = "$Revision$";
+const char *copyright = "2006";
+const char *email = "nagiosplug-devel@lists.sourceforge.net";
+
+#include "common.h"
+#include "netutils.h"
+#include "utils.h"
+
+static char *server_address=NULL;
+static int verbose=0;
+static int zero_offset_bad=0;
+static double owarn=0;
+static double ocrit=0;
+static short do_jitter=0;
+static double jwarn=0;
+static double jcrit=0;
+
+int process_arguments (int, char **);
+void print_help (void);
+void print_usage (void);
+
+/* this structure holds everything in an ntp request/response as per rfc1305 */
+typedef struct {
+ uint8_t flags; /* byte with leapindicator,vers,mode. see macros */
+ uint8_t stratum; /* clock stratum */
+ int8_t poll; /* polling interval */
+ int8_t precision; /* precision of the local clock */
+ int32_t rtdelay; /* total rt delay, as a fixed point num. see macros */
+ uint32_t rtdisp; /* like above, but for max err to primary src */
+ uint32_t refid; /* ref clock identifier */
+ uint64_t refts; /* reference timestamp. local time local clock */
+ uint64_t origts; /* time at which request departed client */
+ uint64_t rxts; /* time at which request arrived at server */
+ uint64_t txts; /* time at which request departed server */
+} ntp_message;
+
+/* bits 1,2 are the leap indicator */
+#define LI_MASK 0xc0
+#define LI(x) ((x&LI_MASK)>>6)
+#define LI_SET(x,y) do{ x |= ((y<<6)&LI_MASK); }while(0)
+/* and these are the values of the leap indicator */
+#define LI_NOWARNING 0x00
+#define LI_EXTRASEC 0x01
+#define LI_MISSINGSEC 0x02
+#define LI_ALARM 0x03
+/* bits 3,4,5 are the ntp version */
+#define VN_MASK 0x38
+#define VN(x) ((x&VN_MASK)>>3)
+#define VN_SET(x,y) do{ x |= ((y<<3)&VN_MASK); }while(0)
+/* bits 6,7,8 are the ntp mode */
+#define MODE_MASK 0x07
+#define MODE(x) (x&MODE_MASK)
+#define MODE_SET(x,y) do{ x |= (y&MODE_MASK); }while(0)
+/* here are some values */
+#define MODE_CLIENT 0x03
+
+/**
+ ** a note about the 32-bit "fixed point" numbers:
+ **
+ they are divided into halves, each being a 16-bit int in network byte order:
+ - the first 16 bits are an int on the left side of a decimal point.
+ - the second 16 bits represent a fraction n/(2^16)
+ likewise for the 64-bit "fixed point" numbers with everything doubled :)
+ **/
+
+/* macros to access the left/right 16 bits of a 32-bit ntp "fixed point"
+ number. note that these can be used as lvalues too */
+#define L16(x) (((uint16_t*)&x)[0])
+#define R16(x) (((uint16_t*)&x)[1])
+/* macros to access the left/right 32 bits of a 64-bit ntp "fixed point"
+ number. these too can be used as lvalues */
+#define L32(x) (((uint32_t*)&x)[0])
+#define R32(x) (((uint32_t*)&x)[1])
+
+/* ntp wants seconds since 1/1/00, epoch is 1/1/70. this is the difference */
+#define EPOCHDIFF 0x83aa7e80UL
+
+/* extract a 32-bit ntp fixed point number into a double */
+#define NTP32asDOUBLE(x) (ntohs(L16(x)) + (double)ntohs(R16(x))/65536.0)
+
+/* likewise for a 64-bit ntp fp number */
+#define NTP64asDOUBLE(n) (double)(((uint64_t)n)?\
+ (ntohl(L32(n))-EPOCHDIFF) + \
+ (.00000001*(0.5+(double)(ntohl(R32(n))/42.94967296))):\
+ 0)
+
+/* convert a struct timeval to a double */
+#define TVasDOUBLE(x) (double)(x.tv_sec+(0.000001*x.tv_usec))
+
+/* convert an ntp 64-bit fp number to a struct timeval */
+#define NTP64toTV(n,t) \
+ do{ if(!n) t.tv_sec = t.tv_usec = 0; \
+ else { \
+ t.tv_sec=ntohl(L32(n))-EPOCHDIFF; \
+ t.tv_usec=(int)(0.5+(double)(ntohl(R32(n))/4294.967296)); \
+ } \
+ }while(0)
+
+/* convert a struct timeval to an ntp 64-bit fp number */
+#define TVtoNTP64(t,n) \
+ do{ if(!t.tv_usec && !t.tv_sec) n=0x0UL; \
+ else { \
+ L32(n)=htonl(t.tv_sec + EPOCHDIFF); \
+ R32(n)=htonl((4294.967296*t.tv_usec)+.5); \
+ } \
+ } while(0)
+
+
+/* calculate the offset of the local clock */
+static inline double calc_offset(const ntp_message *m, const struct timeval *t){
+ double client_tx, peer_rx, peer_tx, client_rx, rtdelay;
+ client_tx = NTP64asDOUBLE(m->origts);
+ peer_rx = NTP64asDOUBLE(m->rxts);
+ peer_tx = NTP64asDOUBLE(m->txts);
+ client_rx=TVasDOUBLE((*t));
+ rtdelay=NTP32asDOUBLE(m->rtdelay);
+ return (.5*((peer_tx-client_rx)+(peer_rx-client_tx)))-rtdelay;
+}
+
+/* print out a ntp packet in human readable/debuggable format */
+void print_packet(const ntp_message *p){
+ struct timeval ref, orig, rx, tx;
+
+ NTP64toTV(p->refts,ref);
+ NTP64toTV(p->origts,orig);
+ NTP64toTV(p->rxts,rx);
+ NTP64toTV(p->txts,tx);
+
+ printf("packet contents:\n");
+ printf("\tflags: 0x%.2x\n", p->flags);
+ printf("\t li=%d (0x%.2x)\n", LI(p->flags), p->flags&LI_MASK);
+ printf("\t vn=%d (0x%.2x)\n", VN(p->flags), p->flags&VN_MASK);
+ printf("\t mode=%d (0x%.2x)\n", MODE(p->flags), p->flags&MODE_MASK);
+ printf("\tstratum = %d\n", p->stratum);
+ printf("\tpoll = %g\n", pow(2, p->poll));
+ printf("\tprecision = %g\n", pow(2, p->precision));
+ printf("\trtdelay = %-.16g\n", NTP32asDOUBLE(p->rtdelay));
+ printf("\trtdisp = %-.16g\n", NTP32asDOUBLE(p->rtdisp));
+ printf("\trefid = %x\n", p->refid);
+ printf("\trefts = %-.16g\n", NTP64asDOUBLE(p->refts));
+ printf("\torigts = %-.16g\n", NTP64asDOUBLE(p->origts));
+ printf("\trxts = %-.16g\n", NTP64asDOUBLE(p->rxts));
+ printf("\ttxts = %-.16g\n", NTP64asDOUBLE(p->txts));
+}
+
+void setup_request(ntp_message *p){
+ struct timeval t;
+
+ memset(p, 0, sizeof(ntp_message));
+ LI_SET(p->flags, LI_ALARM);
+ VN_SET(p->flags, 4);
+ MODE_SET(p->flags, MODE_CLIENT);
+ p->poll=4;
+ p->precision=0xfa;
+ L16(p->rtdelay)=htons(1);
+ L16(p->rtdisp)=htons(1);
+
+ gettimeofday(&t, NULL);
+ TVtoNTP64(t,p->txts);
+}
+
+int process_arguments(int argc, char **argv){
+ int c;
+ int option=0;
+ static struct option longopts[] = {
+ {"version", no_argument, 0, 'V'},
+ {"help", no_argument, 0, 'h'},
+ {"verbose", no_argument, 0, 'v'},
+ {"use-ipv4", no_argument, 0, '4'},
+/* {"use-ipv6", no_argument, 0, '6'}, */
+ {"warning", required_argument, 0, 'w'},
+ {"critical", required_argument, 0, 'c'},
+ {"zero-offset", no_argument, 0, 'O'},
+ {"jwarn", required_argument, 0, 'j'},
+ {"jcrit", required_argument, 0, 'k'},
+ {"timeout", required_argument, 0, 't'},
+ {"hostname", required_argument, 0, 'H'},
+ {0, 0, 0, 0}
+ };
+
+
+ if (argc < 2)
+ usage ("\n");
+
+ while (1) {
+ c = getopt_long (argc, argv, "Vhv4w:c:Oj:k:t:H:", longopts, &option);
+ if (c == -1 || c == EOF || c == 1)
+ break;
+
+ switch (c) {
+ case 'h':
+ print_help();
+ exit(STATE_OK);
+ break;
+ case 'V':
+ print_revision(progname, revision);
+ exit(STATE_OK);
+ break;
+ case 'v':
+ verbose = 1;
+ break;
+ case 'w':
+ owarn = atof(optarg);
+ break;
+ case 'c':
+ ocrit = atof(optarg);
+ break;
+ case 'j':
+ do_jitter=1;
+ jwarn = atof(optarg);
+ break;
+ case 'k':
+ do_jitter=1;
+ jcrit = atof(optarg);
+ break;
+ case 'H':
+ if(is_host(optarg) == FALSE)
+ usage2(_("Invalid hostname/address"), optarg);
+ server_address = strdup(optarg);
+ break;
+ case 't':
+ socket_timeout=atoi(optarg);
+ break;
+ case 'O':
+ zero_offset_bad=1;
+ break;
+ case '?':
+ /* print short usage statement if args not parsable */
+ usage2 (_("Unknown argument"), optarg);
+ break;
+ }
+ }
+
+ if (ocrit < owarn){
+ usage4(_("Critical offset should be larger than warning offset"));
+ }
+
+ if (ocrit < owarn){
+ usage4(_("Critical jitter should be larger than warning jitter"));
+ }
+
+ if(server_address == NULL){
+ usage4(_("Hostname was not supplied"));
+ }
+
+ return 0;
+}
+
+int main(int argc, char *argv[]){
+ int result = STATE_UNKNOWN;
+ int conn;
+ ntp_message m;
+ struct timeval recv_time;
+ double offset=0, jitter=0;
+
+ if (process_arguments (argc, argv) == ERROR)
+ usage4 (_("Could not parse arguments"));
+
+ /* initialize alarm signal handling */
+ signal (SIGALRM, socket_timeout_alarm_handler);
+
+ /* set socket timeout */
+ alarm (socket_timeout);
+
+ setup_request(&m);
+ if(verbose) print_packet(&m);
+ my_udp_connect(server_address, 123, &conn);
+ write(conn, &m, sizeof(ntp_message));
+ read(conn, &m, sizeof(ntp_message));
+ gettimeofday(&recv_time, NULL);
+ if(verbose) print_packet(&m);
+ close(conn);
+
+ offset=calc_offset(&m, &recv_time);
+ printf("total offset: %g\n", offset);
+
+ if(offset > ocrit){
+ printf("NTP CRITICAL: ");
+ result = STATE_CRITICAL;
+ } else if(offset > owarn) {
+ printf("NTP WARNING: ");
+ result = STATE_WARNING;
+ } else {
+ printf("NTP OK: ");
+ result = STATE_OK;
+ }
+
+ /* not implemented yet:
+ jitter=calc_jitter(&m, &recv_time);
+
+ if(do_jitter){
+ if(offset > ocrit){
+ printf("NTP CRITICAL: ");
+ result = STATE_CRITICAL;
+ } else if(offset > owarn) {
+ printf("NTP WARNING: ");
+ result = STATE_WARNING;
+ } else {
+ printf("NTP OK: ");
+ result = STATE_OK;
+ }
+ }
+ */
+
+ printf("Offset %g secs|offset=%g\n", offset, offset);
+
+ if(server_address!=NULL) free(server_address);
+ return result;
+}
+
+
+void print_usage(void){
+ printf("\
+Usage: %s -H <host> [-O] [-w <warn>] [-c <crit>] [-j <warn>] [-k <crit>] [-v verbose]\
+\n", progname);
+}
+
+void print_help(void){
+ print_revision(progname, revision);
+
+ printf ("Copyright (c) 1999 Ethan Galstad\n");
+ printf (COPYRIGHT, copyright, email);
+
+ print_usage();
+ printf (_(UT_HELP_VRSN));
+ printf (_(UT_HOST_PORT), 'p', "123");
+ printf (_(UT_WARN_CRIT));
+ printf (_(UT_TIMEOUT), DEFAULT_SOCKET_TIMEOUT);
+ printf (_(UT_VERBOSE));
+ printf(_(UT_SUPPORT));
+}
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