diff options
Diffstat (limited to 'plugins/check_ntp_peer.c')
| -rw-r--r-- | plugins/check_ntp_peer.c | 877 |
1 files changed, 877 insertions, 0 deletions
diff --git a/plugins/check_ntp_peer.c b/plugins/check_ntp_peer.c new file mode 100644 index 00000000..164d5190 --- /dev/null +++ b/plugins/check_ntp_peer.c @@ -0,0 +1,877 @@ +/****************************************************************************** +* +* Nagios check_ntp plugin +* +* License: GPL +* Copyright (c) 2006 sean finney <seanius@seanius.net> +* Copyright (c) 2007 nagios-plugins team +* +* Last Modified: $Date$ +* +* Description: +* +* This file contains the check_ntp plugin +* +* This plugin to check ntp servers independant of any commandline +* programs or external libraries. +* +* +* License Information: +* +* 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 = "2007"; +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 short do_offset=0; +static char *owarn="60"; +static char *ocrit="120"; +static short do_jitter=0; +static char *jwarn="5000"; +static char *jcrit="10000"; + +int process_arguments (int, char **); +thresholds *offset_thresholds = NULL; +thresholds *jitter_thresholds = NULL; +void print_help (void); +void print_usage (void); + +/* number of times to perform each request to get a good average. */ +#define AVG_NUM 4 + +/* max size of control message data */ +#define MAX_CM_SIZE 468 + +/* 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; + +/* this structure holds data about results from querying offset from a peer */ +typedef struct { + time_t waiting; /* ts set when we started waiting for a response */ + int num_responses; /* number of successfully recieved responses */ + uint8_t stratum; /* copied verbatim from the ntp_message */ + double rtdelay; /* converted from the ntp_message */ + double rtdisp; /* converted from the ntp_message */ + double offset[AVG_NUM]; /* offsets from each response */ + uint8_t flags; /* byte with leapindicator,vers,mode. see macros */ +} ntp_server_results; + +/* this structure holds everything in an ntp control message as per rfc1305 */ +typedef struct { + uint8_t flags; /* byte with leapindicator,vers,mode. see macros */ + uint8_t op; /* R,E,M bits and Opcode */ + uint16_t seq; /* Packet sequence */ + uint16_t status; /* Clock status */ + uint16_t assoc; /* Association */ + uint16_t offset; /* Similar to TCP sequence # */ + uint16_t count; /* # bytes of data */ + char data[MAX_CM_SIZE]; /* ASCII data of the request */ + /* NB: not necessarily NULL terminated! */ +} ntp_control_message; + +/* this is an association/status-word pair found in control packet reponses */ +typedef struct { + uint16_t assoc; + uint16_t status; +} ntp_assoc_status_pair; + +/* 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) +#define VN_RESERVED 0x02 +/* 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 +#define MODE_CONTROLMSG 0x06 +/* In control message, bits 8-10 are R,E,M bits */ +#define REM_MASK 0xe0 +#define REM_RESP 0x80 +#define REM_ERROR 0x40 +#define REM_MORE 0x20 +/* In control message, bits 11 - 15 are opcode */ +#define OP_MASK 0x1f +#define OP_SET(x,y) do{ x |= (y&OP_MASK); }while(0) +#define OP_READSTAT 0x01 +#define OP_READVAR 0x02 +/* In peer status bytes, bits 6,7,8 determine clock selection status */ +#define PEER_SEL(x) ((ntohs(x)>>8)&0x07) +#define PEER_INCLUDED 0x04 +#define PEER_SYNCSOURCE 0x06 + +/** + ** 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((uint64_t)((4294.967296*t.tv_usec)+.5)); \ + } \ + } while(0) + +/* NTP control message header is 12 bytes, plus any data in the data + * field, plus null padding to the nearest 32-bit boundary per rfc. + */ +#define SIZEOF_NTPCM(m) (12+ntohs(m.count)+((m.count)?4-(ntohs(m.count)%4):0)) + +/* finally, a little helper or two for debugging: */ +#define DBG(x) do{if(verbose>1){ x; }}while(0); +#define PRINTSOCKADDR(x) \ + do{ \ + printf("%u.%u.%u.%u", (x>>24)&0xff, (x>>16)&0xff, (x>>8)&0xff, x&0xff);\ + }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; + client_tx = NTP64asDOUBLE(m->origts); + peer_rx = NTP64asDOUBLE(m->rxts); + peer_tx = NTP64asDOUBLE(m->txts); + client_rx=TVasDOUBLE((*t)); + return (.5*((peer_tx-client_rx)+(peer_rx-client_tx))); +} + +/* print out a ntp packet in human readable/debuggable format */ +void print_ntp_message(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 print_ntp_control_message(const ntp_control_message *p){ + int i=0, numpeers=0; + const ntp_assoc_status_pair *peer=NULL; + + printf("control packet contents:\n"); + printf("\tflags: 0x%.2x , 0x%.2x\n", p->flags, p->op); + 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("\t response=%d (0x%.2x)\n", (p->op&REM_RESP)>0, p->op&REM_RESP); + printf("\t more=%d (0x%.2x)\n", (p->op&REM_MORE)>0, p->op&REM_MORE); + printf("\t error=%d (0x%.2x)\n", (p->op&REM_ERROR)>0, p->op&REM_ERROR); + printf("\t op=%d (0x%.2x)\n", p->op&OP_MASK, p->op&OP_MASK); + printf("\tsequence: %d (0x%.2x)\n", ntohs(p->seq), ntohs(p->seq)); + printf("\tstatus: %d (0x%.2x)\n", ntohs(p->status), ntohs(p->status)); + printf("\tassoc: %d (0x%.2x)\n", ntohs(p->assoc), ntohs(p->assoc)); + printf("\toffset: %d (0x%.2x)\n", ntohs(p->offset), ntohs(p->offset)); + printf("\tcount: %d (0x%.2x)\n", ntohs(p->count), ntohs(p->count)); + numpeers=ntohs(p->count)/(sizeof(ntp_assoc_status_pair)); + if(p->op&REM_RESP && p->op&OP_READSTAT){ + peer=(ntp_assoc_status_pair*)p->data; + for(i=0;i<numpeers;i++){ + printf("\tpeer id %.2x status %.2x", + ntohs(peer[i].assoc), ntohs(peer[i].status)); + if (PEER_SEL(peer[i].status) >= PEER_INCLUDED){ + if(PEER_SEL(peer[i].status) >= PEER_SYNCSOURCE){ + printf(" <-- current sync source"); + } else { + printf(" <-- current sync candidate"); + } + } + printf("\n"); + } + } +} + +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=(int8_t)0xfa; + L16(p->rtdelay)=htons(1); + L16(p->rtdisp)=htons(1); + + gettimeofday(&t, NULL); + TVtoNTP64(t,p->txts); +} + +/* select the "best" server from a list of servers, and return its index. + * this is done by filtering servers based on stratum, dispersion, and + * finally round-trip delay. */ +int best_offset_server(const ntp_server_results *slist, int nservers){ + int i=0, j=0, cserver=0, candidates[5], csize=0; + + /* for each server */ + for(cserver=0; cserver<nservers; cserver++){ + /* sort out servers with error flags */ + if ( LI(slist[cserver].flags) != LI_NOWARNING ){ + if (verbose) printf("discarding peer id %d: flags=%d\n", cserver, LI(slist[cserver].flags)); + break; + } + + /* compare it to each of the servers already in the candidate list */ + for(i=0; i<csize; i++){ + /* does it have an equal or better stratum? */ + if(slist[cserver].stratum <= slist[i].stratum){ + /* does it have an equal or better dispersion? */ + if(slist[cserver].rtdisp <= slist[i].rtdisp){ + /* does it have a better rtdelay? */ + if(slist[cserver].rtdelay < slist[i].rtdelay){ + break; + } + } + } + } + + /* if we haven't reached the current list's end, move everyone + * over one to the right, and insert the new candidate */ + if(i<csize){ + for(j=5; j>i; j--){ + candidates[j]=candidates[j-1]; + } + } + /* regardless, if they should be on the list... */ + if(i<5) { + candidates[i]=cserver; + if(csize<5) csize++; + /* otherwise discard the server */ + } else { + DBG(printf("discarding peer id %d\n", cserver)); + } + } + + if(csize>0) { + DBG(printf("best server selected: peer %d\n", candidates[0])); + return candidates[0]; + } else { + DBG(printf("no peers meeting synchronization criteria :(\n")); + return -1; + } +} + +/* do everything we need to get the total average offset + * - we use a certain amount of parallelization with poll() to ensure + * we don't waste time sitting around waiting for single packets. + * - we also "manually" handle resolving host names and connecting, because + * we have to do it in a way that our lazy macros don't handle currently :( */ +double offset_request(const char *host, int *status){ + int i=0, j=0, ga_result=0, num_hosts=0, *socklist=NULL, respnum=0; + int servers_completed=0, one_written=0, one_read=0, servers_readable=0, best_index=-1; + time_t now_time=0, start_ts=0; + ntp_message *req=NULL; + double avg_offset=0.; + struct timeval recv_time; + struct addrinfo *ai=NULL, *ai_tmp=NULL, hints; + struct pollfd *ufds=NULL; + ntp_server_results *servers=NULL; + + /* setup hints to only return results from getaddrinfo that we'd like */ + memset(&hints, 0, sizeof(struct addrinfo)); + hints.ai_family = address_family; + hints.ai_protocol = IPPROTO_UDP; + hints.ai_socktype = SOCK_DGRAM; + + /* fill in ai with the list of hosts resolved by the host name */ + ga_result = getaddrinfo(host, "123", &hints, &ai); + if(ga_result!=0){ + die(STATE_UNKNOWN, "error getting address for %s: %s\n", + host, gai_strerror(ga_result)); + } + + /* count the number of returned hosts, and allocate stuff accordingly */ + for(ai_tmp=ai; ai_tmp!=NULL; ai_tmp=ai_tmp->ai_next){ num_hosts++; } + req=(ntp_message*)malloc(sizeof(ntp_message)*num_hosts); + if(req==NULL) die(STATE_UNKNOWN, "can not allocate ntp message array"); + socklist=(int*)malloc(sizeof(int)*num_hosts); + if(socklist==NULL) die(STATE_UNKNOWN, "can not allocate socket array"); + ufds=(struct pollfd*)malloc(sizeof(struct pollfd)*num_hosts); + if(ufds==NULL) die(STATE_UNKNOWN, "can not allocate socket array"); + servers=(ntp_server_results*)malloc(sizeof(ntp_server_results)*num_hosts); + if(servers==NULL) die(STATE_UNKNOWN, "can not allocate server array"); + memset(servers, 0, sizeof(ntp_server_results)*num_hosts); + + /* setup each socket for writing, and the corresponding struct pollfd */ + ai_tmp=ai; + for(i=0;ai_tmp;i++){ + socklist[i]=socket(ai_tmp->ai_family, SOCK_DGRAM, IPPROTO_UDP); + if(socklist[i] == -1) { + perror(NULL); + die(STATE_UNKNOWN, "can not create new socket"); + } + if(connect(socklist[i], ai_tmp->ai_addr, ai_tmp->ai_addrlen)){ + die(STATE_UNKNOWN, "can't create socket connection"); + } else { + ufds[i].fd=socklist[i]; + ufds[i].events=POLLIN; + ufds[i].revents=0; + } + ai_tmp = ai_tmp->ai_next; + } + + /* now do AVG_NUM checks to each host. we stop before timeout/2 seconds + * have passed in order to ensure post-processing and jitter time. */ + now_time=start_ts=time(NULL); + while(servers_completed<num_hosts && now_time-start_ts <= socket_timeout/2){ + /* loop through each server and find each one which hasn't + * been touched in the past second or so and is still lacking + * some responses. for each of these servers, send a new request, + * and update the "waiting" timestamp with the current time. */ + one_written=0; + now_time=time(NULL); + + for(i=0; i<num_hosts; i++){ + if(servers[i].waiting<now_time && servers[i].num_responses<AVG_NUM){ + if(verbose && servers[i].waiting != 0) printf("re-"); + if(verbose) printf("sending request to peer %d\n", i); + setup_request(&req[i]); + write(socklist[i], &req[i], sizeof(ntp_message)); + servers[i].waiting=now_time; + one_written=1; + break; + } + } + + /* quickly poll for any sockets with pending data */ + servers_readable=poll(ufds, num_hosts, 100); + if(servers_readable==-1){ + perror("polling ntp sockets"); + die(STATE_UNKNOWN, "communication errors"); + } + + /* read from any sockets with pending data */ + for(i=0; servers_readable && i<num_hosts; i++){ + if(ufds[i].revents&POLLIN && servers[i].num_responses < AVG_NUM){ + if(verbose) { + printf("response from peer %d: ", i); + } + + read(ufds[i].fd, &req[i], sizeof(ntp_message)); + gettimeofday(&recv_time, NULL); + DBG(print_ntp_message(&req[i])); + respnum=servers[i].num_responses++; + servers[i].offset[respnum]=calc_offset(&req[i], &recv_time); + if(verbose) { + printf("offset %.10g\n", servers[i].offset[respnum]); + } + servers[i].stratum=req[i].stratum; + servers[i].rtdisp=NTP32asDOUBLE(req[i].rtdisp); + servers[i].rtdelay=NTP32asDOUBLE(req[i].rtdelay); + servers[i].waiting=0; + servers[i].flags=req[i].flags; + servers_readable--; + one_read = 1; + if(servers[i].num_responses==AVG_NUM) servers_completed++; + } + } + /* lather, rinse, repeat. */ + } + + if (one_read == 0) { + die(STATE_CRITICAL, "NTP CRITICAL: No response from NTP server\n"); + } + + /* now, pick the best server from the list */ + best_index=best_offset_server(servers, num_hosts); + if(best_index < 0){ + *status=STATE_UNKNOWN; + } else { + /* finally, calculate the average offset */ + for(i=0; i<servers[best_index].num_responses;i++){ + avg_offset+=servers[best_index].offset[j]; + } + avg_offset/=servers[best_index].num_responses; + } + + /* cleanup */ + /* FIXME: Not closing the socket to avoid re-use of the local port + * which can cause old NTP packets to be read instead of NTP control + * pactets in jitter_request(). THERE MUST BE ANOTHER WAY... + * for(j=0; j<num_hosts; j++){ close(socklist[j]); } */ + free(socklist); + free(ufds); + free(servers); + free(req); + freeaddrinfo(ai); + + if(verbose) printf("overall average offset: %.10g\n", avg_offset); + return avg_offset; +} + +void +setup_control_request(ntp_control_message *p, uint8_t opcode, uint16_t seq){ + memset(p, 0, sizeof(ntp_control_message)); + LI_SET(p->flags, LI_NOWARNING); + VN_SET(p->flags, VN_RESERVED); + MODE_SET(p->flags, MODE_CONTROLMSG); + OP_SET(p->op, opcode); + p->seq = htons(seq); + /* Remaining fields are zero for requests */ +} + +/* XXX handle responses with the error bit set */ +double jitter_request(const char *host, int *status){ + int conn=-1, i, npeers=0, num_candidates=0, syncsource_found=0; + int run=0, min_peer_sel=PEER_INCLUDED, num_selected=0, num_valid=0; + int peers_size=0, peer_offset=0; + ntp_assoc_status_pair *peers=NULL; + ntp_control_message req; + const char *getvar = "jitter"; + double rval = 0.0, jitter = -1.0; + char *startofvalue=NULL, *nptr=NULL; + void *tmp; + + /* Long-winded explanation: + * Getting the jitter requires a number of steps: + * 1) Send a READSTAT request. + * 2) Interpret the READSTAT reply + * a) The data section contains a list of peer identifiers (16 bits) + * and associated status words (16 bits) + * b) We want the value of 0x06 in the SEL (peer selection) value, + * which means "current synchronizatin source". If that's missing, + * we take anything better than 0x04 (see the rfc for details) but + * set a minimum of warning. + * 3) Send a READVAR request for information on each peer identified + * in 2b greater than the minimum selection value. + * 4) Extract the jitter value from the data[] (it's ASCII) + */ + my_udp_connect(server_address, 123, &conn); + + /* keep sending requests until the server stops setting the + * REM_MORE bit, though usually this is only 1 packet. */ + do{ + setup_control_request(&req, OP_READSTAT, 1); + DBG(printf("sending READSTAT request")); + write(conn, &req, SIZEOF_NTPCM(req)); + DBG(print_ntp_control_message(&req)); + /* Attempt to read the largest size packet possible */ + req.count=htons(MAX_CM_SIZE); + DBG(printf("recieving READSTAT response")) + read(conn, &req, SIZEOF_NTPCM(req)); + DBG(print_ntp_control_message(&req)); + /* Each peer identifier is 4 bytes in the data section, which + * we represent as a ntp_assoc_status_pair datatype. + */ + peers_size+=ntohs(req.count); + if((tmp=realloc(peers, peers_size)) == NULL) + free(peers), die(STATE_UNKNOWN, "can not (re)allocate 'peers' buffer\n"); + peers=tmp; + memcpy((void*)((ptrdiff_t)peers+peer_offset), (void*)req.data, ntohs(req.count)); + npeers=peers_size/sizeof(ntp_assoc_status_pair); + peer_offset+=ntohs(req.count); + } while(req.op&REM_MORE); + + /* first, let's find out if we have a sync source, or if there are + * at least some candidates. in the case of the latter we'll issue + * a warning but go ahead with the check on them. */ + for (i = 0; i < npeers; i++){ + if (PEER_SEL(peers[i].status) >= PEER_INCLUDED){ + num_candidates++; + if(PEER_SEL(peers[i].status) >= PEER_SYNCSOURCE){ + syncsource_found=1; + min_peer_sel=PEER_SYNCSOURCE; + } + } + } + if(verbose) printf("%d candiate peers available\n", num_candidates); + if(verbose && syncsource_found) printf("synchronization source found\n"); + if(! syncsource_found){ + *status = STATE_UNKNOWN; + if(verbose) printf("warning: no synchronization source found\n"); + } + + + for (run=0; run<AVG_NUM; run++){ + if(verbose) printf("jitter run %d of %d\n", run+1, AVG_NUM); + for (i = 0; i < npeers; i++){ + /* Only query this server if it is the current sync source */ + if (PEER_SEL(peers[i].status) >= min_peer_sel){ + num_selected++; + setup_control_request(&req, OP_READVAR, 2); + req.assoc = peers[i].assoc; + /* By spec, putting the variable name "jitter" in the request + * should cause the server to provide _only_ the jitter value. + * thus reducing net traffic, guaranteeing us only a single + * datagram in reply, and making intepretation much simpler + */ + /* Older servers doesn't know what jitter is, so if we get an + * error on the first pass we redo it with "dispersion" */ + strncpy(req.data, getvar, MAX_CM_SIZE-1); + req.count = htons(strlen(getvar)); + DBG(printf("sending READVAR request...\n")); + write(conn, &req, SIZEOF_NTPCM(req)); + DBG(print_ntp_control_message(&req)); + + req.count = htons(MAX_CM_SIZE); + DBG(printf("recieving READVAR response...\n")); + read(conn, &req, SIZEOF_NTPCM(req)); + DBG(print_ntp_control_message(&req)); + + if(req.op&REM_ERROR && strstr(getvar, "jitter")) { + if(verbose) printf("The 'jitter' command failed (old ntp server?)\nRestarting with 'dispersion'...\n"); + getvar = "dispersion"; + num_selected--; + i--; + continue; + } + + /* get to the float value */ + if(verbose) { + printf("parsing jitter from peer %.2x: ", ntohs(peers[i].assoc)); + } + startofvalue = strchr(req.data, '='); + if(startofvalue != NULL) { + startofvalue++; + jitter = strtod(startofvalue, &nptr); + } + if(startofvalue == NULL || startofvalue==nptr){ + printf("warning: unable to read server jitter response.\n"); + *status = STATE_UNKNOWN; + } else { + if(verbose) printf("%g\n", jitter); + num_valid++; + rval += jitter; + } + } + } + if(verbose){ + printf("jitter parsed from %d/%d peers\n", num_valid, num_selected); + } + } + + rval = num_valid ? rval / num_valid : -1.0; + + close(conn); + if(peers!=NULL) free(peers); + /* If we return -1.0, it means no synchronization source was found */ + return rval; +} + +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'}, + {"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, "Vhv46w:c:j: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++; + break; + case 'w': + do_offset=1; + owarn = optarg; + break; + case 'c': + do_offset=1; + ocrit = optarg; + break; + case 'j': + do_jitter=1; + jwarn = optarg; + break; + case 'k': + do_jitter=1; + jcrit = 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 '4': + address_family = AF_INET; + break; + case '6': +#ifdef USE_IPV6 + address_family = AF_INET6; +#else + usage4 (_("IPv6 support not available")); +#endif + break; + case '?': + /* print short usage statement if args not parsable */ + usage5 (); + break; + } + } + + if(server_address == NULL){ + usage4(_("Hostname was not supplied")); + } + + return 0; +} + +char *perfd_offset (double offset) +{ + return fperfdata ("offset", offset, "s", + TRUE, offset_thresholds->warning->end, + TRUE, offset_thresholds->critical->end, + FALSE, 0, FALSE, 0); +} + +char *perfd_jitter (double jitter) +{ + return fperfdata ("jitter", jitter, "s", + do_jitter, jitter_thresholds->warning->end, + do_jitter, jitter_thresholds->critical->end, + TRUE, 0, FALSE, 0); +} + +int main(int argc, char *argv[]){ + int result, offset_result, jitter_result; + double offset=0, jitter=0; + char *result_line, *perfdata_line; + + result = offset_result = jitter_result = STATE_OK; + + if (process_arguments (argc, argv) == ERROR) + usage4 (_("Could not parse arguments")); + + set_thresholds(&offset_thresholds, owarn, ocrit); + set_thresholds(&jitter_thresholds, jwarn, jcrit); + + /* initialize alarm signal handling */ + signal (SIGALRM, socket_timeout_alarm_handler); + + /* set socket timeout */ + alarm (socket_timeout); + + offset = offset_request(server_address, &offset_result); + /* check_ntp used to always return CRITICAL if offset_result == STATE_UNKNOWN. + * Now we'll only do that is the offset thresholds were set */ + if (do_offset && offset_result == STATE_UNKNOWN) { + result = STATE_CRITICAL; + } else { + result = get_status(fabs(offset), offset_thresholds); + } + + /* If not told to check the jitter, we don't even send packets. + * jitter is checked using NTP control packets, which not all + * servers recognize. Trying to check the jitter on OpenNTPD + * (for example) will result in an error + */ + if(do_jitter){ + jitter=jitter_request(server_address, &jitter_result); + result = max_state_alt(result, get_status(jitter, jitter_thresholds)); + /* -1 indicates that we couldn't calculate the jitter + * Only overrides STATE_OK from the offset */ + if(jitter == -1.0 && result == STATE_OK) + result = STATE_UNKNOWN; + } + result = max_state_alt(result, jitter_result); + + switch (result) { + case STATE_CRITICAL : + asprintf(&result_line, "NTP CRITICAL:"); + break; + case STATE_WARNING : + asprintf(&result_line, "NTP WARNING:"); + break; + case STATE_OK : + asprintf(&result_line, "NTP OK:"); + break; + default : + asprintf(&result_line, "NTP UNKNOWN:"); + break; + } + if(offset_result == STATE_UNKNOWN){ + asprintf(&result_line, "%s %s", result_line, _("Offset unknown")); + asprintf(&perfdata_line, ""); + } else { + asprintf(&result_line, "%s Offset %.10g secs", result_line, offset); + asprintf(&perfdata_line, "%s", perfd_offset(offset)); + } + if (do_jitter) { + asprintf(&result_line, "%s, jitter=%f", result_line, jitter); + asprintf(&perfdata_line, "%s %s", perfdata_line, perfd_jitter(jitter)); + } + printf("%s|%s\n", result_line, perfdata_line); + + if(server_address!=NULL) free(server_address); + return result; +} + + + +void print_help(void){ + print_revision(progname, revision); + + printf ("Copyright (c) 2006 Sean Finney\n"); + printf (COPYRIGHT, copyright, email); + + printf ("%s\n", _("This plugin checks the selected ntp server")); + + printf ("\n\n"); + + print_usage(); + printf (_(UT_HELP_VRSN)); + printf (_(UT_HOST_PORT), 'p', "123"); + printf (" %s\n", "-w, --warning=THRESHOLD"); + printf (" %s\n", _("Offset to result in warning status (seconds)")); + printf (" %s\n", "-c, --critical=THRESHOLD"); + printf (" %s\n", _("Offset to result in critical status (seconds)")); + printf (" %s\n", "-j, --warning=THRESHOLD"); + printf (" %s\n", _("Warning threshold for jitter")); + printf (" %s\n", "-k, --critical=THRESHOLD"); + printf (" %s\n", _("Critical threshold for jitter")); + printf (_(UT_TIMEOUT), DEFAULT_SOCKET_TIMEOUT); + printf (_(UT_VERBOSE)); + + printf("\n"); + printf("%s\n", _("Notes:")); + printf(" %s\n", _("See:")); + printf(" %s\n", ("http://nagiosplug.sourceforge.net/developer-guidelines.html#THRESHOLDFORMAT")); + printf(" %s\n", _("for THRESHOLD format and examples.")); + + printf("\n"); + printf("%s\n", _("Examples:")); + printf(" %s\n", _("Normal offset check:")); + printf(" %s\n", ("./check_ntp -H ntpserv -w 0.5 -c 1")); + printf(" %s\n", _("Check jitter too, avoiding critical notifications if jitter isn't available")); + printf(" %s\n", _("(See Notes above for more details on thresholds formats):")); + printf(" %s\n", ("./check_ntp -H ntpserv -w 0.5 -c 1 -j -1:100 -k -1:200")); + + printf (_(UT_SUPPORT)); +} + +void +print_usage(void) +{ + printf (_("Usage:")); + printf(" %s -H <host> [-w <warn>] [-c <crit>] [-j <warn>] [-k <crit>] [-v verbose]\n", progname); +} |