static void
process_pps(
peerT * const peer ,
json_ctx * const jctx ,
const l_fp * const rtime)
{
clockprocT * const pp = peer->procptr;
gpsd_unitT * const up = (gpsd_unitT *)pp->unitptr;
struct timespec ts;
errno = 0;
ts.tv_sec = (time_t)json_object_lookup_int(
jctx, 0, "clock_sec");
if (up->fl_nsec)
ts.tv_nsec = json_object_lookup_int(
jctx, 0, "clock_nsec");
else
ts.tv_nsec = json_object_lookup_int(
jctx, 0, "clock_musec") * 1000;
if (0 != errno)
goto fail;
up->pps_local = *rtime;
/* get fudged receive time */
up->pps_recvt = tspec_stamp_to_lfp(ts);
L_SUB(&up->pps_recvt, &up->pps_fudge);
/* map to next full second as reference time stamp */
up->pps_stamp = up->pps_recvt;
L_ADDUF(&up->pps_stamp, 0x80000000u);
up->pps_stamp.l_uf = 0;
pp->lastrec = up->pps_stamp;
DPRINTF(2, ("GPSD_JSON(%d): process_pps, stamp='%s', recvt='%s'\n",
up->unit,
gmprettydate(&up->pps_stamp),
gmprettydate(&up->pps_recvt)));
/* When we have a time pulse, clear the TPV flag: the
* PPS is only valid for the >NEXT< TPV value!
*/
up->fl_pps = -1;
up->fl_tpv = 0;
return;
fail:
DPRINTF(2, ("GPSD_JSON(%d): process_pps FAILED, nsec=%d stamp='%s', recvt='%s'\n",
up->unit, up->fl_nsec,
gmprettydate(&up->pps_stamp),
gmprettydate(&up->pps_recvt)));
up->tc_breply += 1;
}
/*
* ntp_monitor - record stats about this packet
*
* Returns supplied restriction flags, with RES_LIMITED and RES_KOD
* cleared unless the packet should not be responded to normally
* (RES_LIMITED) and possibly should trigger a KoD response (RES_KOD).
* The returned flags are saved in the MRU entry, so that it reflects
* whether the last packet from that source triggered rate limiting,
* and if so, possible KoD response. This implies you can not tell
* whether a given address is eligible for rate limiting/KoD from the
* monlist restrict bits, only whether or not the last packet triggered
* such responses. ntpdc -c reslist lets you see whether RES_LIMITED
* or RES_KOD is lit for a particular address before ntp_monitor()'s
* typical dousing.
*/
u_short
ntp_monitor(
struct recvbuf *rbufp,
u_short flags
)
{
l_fp interval_fp;
struct pkt * pkt;
mon_entry * mon;
mon_entry * oldest;
int oldest_age;
u_int hash;
u_short restrict_mask;
u_char mode;
u_char version;
int interval;
int head; /* headway increment */
int leak; /* new headway */
int limit; /* average threshold */
REQUIRE(rbufp != NULL);
if (mon_enabled == MON_OFF)
return ~(RES_LIMITED | RES_KOD) & flags;
pkt = &rbufp->recv_pkt;
hash = MON_HASH(&rbufp->recv_srcadr);
mode = PKT_MODE(pkt->li_vn_mode);
version = PKT_VERSION(pkt->li_vn_mode);
mon = mon_hash[hash];
/*
* We keep track of all traffic for a given IP in one entry,
* otherwise cron'ed ntpdate or similar evades RES_LIMITED.
*/
for (; mon != NULL; mon = mon->hash_next)
if (SOCK_EQ(&mon->rmtadr, &rbufp->recv_srcadr))
break;
if (mon != NULL) {
interval_fp = rbufp->recv_time;
L_SUB(&interval_fp, &mon->last);
/* add one-half second to round up */
L_ADDUF(&interval_fp, 0x80000000);
interval = interval_fp.l_i;
mon->last = rbufp->recv_time;
NSRCPORT(&mon->rmtadr) = NSRCPORT(&rbufp->recv_srcadr);
mon->count++;
restrict_mask = flags;
mon->vn_mode = VN_MODE(version, mode);
/* Shuffle to the head of the MRU list. */
UNLINK_DLIST(mon, mru);
LINK_DLIST(mon_mru_list, mon, mru);
/*
* At this point the most recent arrival is first in the
* MRU list. Decrease the counter by the headway, but
* not less than zero.
*/
mon->leak -= interval;
mon->leak = max(0, mon->leak);
head = 1 << ntp_minpoll;
leak = mon->leak + head;
limit = NTP_SHIFT * head;
DPRINTF(2, ("MRU: interval %d headway %d limit %d\n",
interval, leak, limit));
/*
* If the minimum and average thresholds are not
* exceeded, douse the RES_LIMITED and RES_KOD bits and
* increase the counter by the headway increment. Note
* that we give a 1-s grace for the minimum threshold
* and a 2-s grace for the headway increment. If one or
* both thresholds are exceeded and the old counter is
* less than the average threshold, set the counter to
* the average threshold plus the increment and leave
* the RES_LIMITED and RES_KOD bits lit. Otherwise,
* leave the counter alone and douse the RES_KOD bit.
* This rate-limits the KoDs to no less than the average
* headway.
*/
if (interval + 1 >= ntp_minpkt && leak < limit) {
mon->leak = leak - 2;
restrict_mask &= ~(RES_LIMITED | RES_KOD);
} else if (mon->leak < limit)
mon->leak = limit + head;
else
restrict_mask &= ~RES_KOD;
mon->flags = restrict_mask;
return mon->flags;
}
/*
* If we got here, this is the first we've heard of this
* guy. Get him some memory, either from the free list
* or from the tail of the MRU list.
*
* The following ntp.conf "mru" knobs come into play determining
* the depth (or count) of the MRU list:
* - mru_mindepth ("mru mindepth") is a floor beneath which
* entries are kept without regard to their age. The
* default is 600 which matches the longtime implementation
* limit on the total number of entries.
* - mru_maxage ("mru maxage") is a ceiling on the age in
* seconds of entries. Entries older than this are
* reclaimed once mon_mindepth is exceeded. 64s default.
* Note that entries older than this can easily survive
* as they are reclaimed only as needed.
* - mru_maxdepth ("mru maxdepth") is a hard limit on the
* number of entries.
* - "mru maxmem" sets mru_maxdepth to the number of entries
* which fit in the given number of kilobytes. The default is
* 1024, or 1 megabyte.
* - mru_initalloc ("mru initalloc" sets the count of the
* initial allocation of MRU entries.
* - "mru initmem" sets mru_initalloc in units of kilobytes.
* The default is 4.
* - mru_incalloc ("mru incalloc" sets the number of entries to
* allocate on-demand each time the free list is empty.
* - "mru incmem" sets mru_incalloc in units of kilobytes.
* The default is 4.
* Whichever of "mru maxmem" or "mru maxdepth" occurs last in
* ntp.conf controls. Similarly for "mru initalloc" and "mru
* initmem", and for "mru incalloc" and "mru incmem".
*/
if (mru_entries < mru_mindepth) {
if (NULL == mon_free)
mon_getmoremem();
UNLINK_HEAD_SLIST(mon, mon_free, hash_next);
} else {
oldest = TAIL_DLIST(mon_mru_list, mru);
oldest_age = 0; /* silence uninit warning */
if (oldest != NULL) {
interval_fp = rbufp->recv_time;
L_SUB(&interval_fp, &oldest->last);
/* add one-half second to round up */
L_ADDUF(&interval_fp, 0x80000000);
oldest_age = interval_fp.l_i;
}
/* note -1 is legal for mru_maxage (disables) */
if (oldest != NULL && mru_maxage < oldest_age) {
mon_reclaim_entry(oldest);
mon = oldest;
} else if (mon_free != NULL || mru_alloc <
mru_maxdepth) {
if (NULL == mon_free)
mon_getmoremem();
UNLINK_HEAD_SLIST(mon, mon_free, hash_next);
/* Preempt from the MRU list if old enough. */
} else if (ntp_random() / (2. * FRAC) >
(double)oldest_age / mon_age) {
return ~(RES_LIMITED | RES_KOD) & flags;
} else {
mon_reclaim_entry(oldest);
mon = oldest;
}
}
INSIST(mon != NULL);
/*
* Got one, initialize it
*/
mru_entries++;
mru_peakentries = max(mru_peakentries, mru_entries);
mon->last = rbufp->recv_time;
mon->first = mon->last;
mon->count = 1;
mon->flags = ~(RES_LIMITED | RES_KOD) & flags;
mon->leak = 0;
memcpy(&mon->rmtadr, &rbufp->recv_srcadr, sizeof(mon->rmtadr));
mon->vn_mode = VN_MODE(version, mode);
mon->lcladr = rbufp->dstadr;
mon->cast_flags = (u_char)(((rbufp->dstadr->flags &
INT_MCASTOPEN) && rbufp->fd == mon->lcladr->fd) ? MDF_MCAST
: rbufp->fd == mon->lcladr->bfd ? MDF_BCAST : MDF_UCAST);
/*
* Drop him into front of the hash table. Also put him on top of
* the MRU list.
*/
LINK_SLIST(mon_hash[hash], mon, hash_next);
LINK_DLIST(mon_mru_list, mon, mru);
return mon->flags;
}
/*
* request - send a configuration request to the server, wait for a response
*/
static int
request(
struct conf_peer *conf
)
{
struct sock_timeval tvout;
struct req_pkt reqpkt;
size_t req_len;
size_t total_len; /* req_len plus keyid & digest */
fd_set fdset;
l_fp ts;
char * pch;
char * pchEnd;
l_fp * pts;
keyid_t *pkeyid;
int n;
#ifdef SYS_WINNT
HANDLE hReadWriteEvent = NULL;
BOOL ret;
DWORD NumberOfBytesWritten, NumberOfBytesRead, dwWait;
OVERLAPPED overlap;
#endif /* SYS_WINNT */
checkparent(); /* make sure our guy is still running */
if (sockfd == INVALID_SOCKET)
openntp();
#ifdef SYS_WINNT
hReadWriteEvent = CreateEvent(NULL, FALSE, FALSE, NULL);
#endif /* SYS_WINNT */
/*
* Try to clear out any previously received traffic so it
* doesn't fool us. Note the socket is nonblocking.
*/
tvout.tv_sec = 0;
tvout.tv_usec = 0;
FD_ZERO(&fdset);
FD_SET(sockfd, &fdset);
while (select(sockfd + 1, &fdset, (fd_set *)0, (fd_set *)0, &tvout) >
0) {
recv(sockfd, (char *)&reqpkt, sizeof(reqpkt), 0);
FD_ZERO(&fdset);
FD_SET(sockfd, &fdset);
}
/*
* Make up a request packet with the configuration info
*/
memset(&reqpkt, 0, sizeof(reqpkt));
reqpkt.rm_vn_mode = RM_VN_MODE(0, 0, 0);
reqpkt.auth_seq = AUTH_SEQ(1, 0); /* authenticated, no seq */
reqpkt.implementation = IMPL_XNTPD; /* local implementation */
reqpkt.request = REQ_CONFIG; /* configure a new peer */
reqpkt.err_nitems = ERR_NITEMS(0, 1); /* one item */
reqpkt.mbz_itemsize = MBZ_ITEMSIZE(sizeof(*conf));
/* Make sure mbz_itemsize <= sizeof reqpkt.data */
if (sizeof(*conf) > sizeof(reqpkt.data)) {
msyslog(LOG_ERR,
"Bletch: conf_peer is too big for reqpkt.data!");
resolver_exit(1);
}
memcpy(reqpkt.data, conf, sizeof(*conf));
if (sys_authenticate && req_hashlen > 16) {
pch = reqpkt.data;
/* 32-bit alignment */
pch += (sizeof(*conf) + 3) & ~3;
pts = (void *)pch;
pkeyid = (void *)(pts + 1);
pchEnd = (void *)pkeyid;
req_len = pchEnd - (char *)&reqpkt;
pchEnd = (void *)(pkeyid + 1);
pchEnd += req_hashlen;
total_len = pchEnd - (char *)&reqpkt;
if (total_len > sizeof(reqpkt)) {
msyslog(LOG_ERR,
"intres total_len %u limit is %u (%u octet digest)\n",
total_len, sizeof(reqpkt),
req_hashlen);
resolver_exit(1);
}
} else {
pts = &reqpkt.tstamp;
pkeyid = &reqpkt.keyid;
req_len = REQ_LEN_NOMAC;
}
*pkeyid = htonl(req_keyid);
get_systime(&ts);
L_ADDUF(&ts, SKEWTIME);
HTONL_FP(&ts, pts);
if (sys_authenticate) {
n = authencrypt(req_keyid, (void *)&reqpkt, req_len);
if ((size_t)n != req_hashlen + sizeof(reqpkt.keyid)) {
msyslog(LOG_ERR,
"intres maclen %d expected %u\n",
n, req_hashlen + sizeof(reqpkt.keyid));
resolver_exit(1);
}
req_len += n;
}
/*
* Done. Send it.
*/
#ifndef SYS_WINNT
n = send(sockfd, (char *)&reqpkt, req_len, 0);
if (n < 0) {
msyslog(LOG_ERR, "send to NTP server failed: %m");
return 0; /* maybe should exit */
}
#else
/* In the NT world, documentation seems to indicate that there
* exist _write and _read routines that can be used to do blocking
* I/O on sockets. Problem is these routines require a socket
* handle obtained through the _open_osf_handle C run-time API
* of which there is no explanation in the documentation. We need
* nonblocking write's and read's anyway for our purpose here.
* We're therefore forced to deviate a little bit from the Unix
* model here and use the ReadFile and WriteFile Win32 I/O API's
* on the socket
*/
overlap.Offset = overlap.OffsetHigh = (DWORD)0;
overlap.hEvent = hReadWriteEvent;
ret = WriteFile((HANDLE)sockfd, (char *)&reqpkt, req_len,
NULL, (LPOVERLAPPED)&overlap);
if ((ret == FALSE) && (GetLastError() != ERROR_IO_PENDING)) {
msyslog(LOG_ERR, "send to NTP server failed: %m");
return 0;
}
dwWait = WaitForSingleObject(hReadWriteEvent, (DWORD) TIMEOUT_SEC * 1000);
if ((dwWait == WAIT_FAILED) || (dwWait == WAIT_TIMEOUT)) {
if (dwWait == WAIT_FAILED)
msyslog(LOG_ERR, "WaitForSingleObject failed: %m");
return 0;
}
if (!GetOverlappedResult((HANDLE)sockfd, (LPOVERLAPPED)&overlap,
(LPDWORD)&NumberOfBytesWritten, FALSE)) {
msyslog(LOG_ERR, "GetOverlappedResult for WriteFile fails: %m");
return 0;
}
#endif /* SYS_WINNT */
/*
* Wait for a response. A weakness of the mode 7 protocol used
* is that there is no way to associate a response with a
* particular request, i.e. the response to this configuration
* request is indistinguishable from that to any other. I should
* fix this some day. In any event, the time out is fairly
* pessimistic to make sure that if an answer is coming back
* at all, we get it.
*/
for (;;) {
FD_ZERO(&fdset);
FD_SET(sockfd, &fdset);
tvout.tv_sec = TIMEOUT_SEC;
tvout.tv_usec = TIMEOUT_USEC;
n = select(sockfd + 1, &fdset, (fd_set *)0,
(fd_set *)0, &tvout);
if (n < 0) {
if (errno != EINTR)
msyslog(LOG_ERR, "select() fails: %m");
return 0;
} else if (n == 0) {
#ifdef DEBUG
if (debug)
msyslog(LOG_INFO, "ntp_intres select() returned 0.");
#endif
return 0;
}
#ifndef SYS_WINNT
n = recv(sockfd, (char *)&reqpkt, sizeof(reqpkt), 0);
if (n <= 0) {
if (n < 0) {
msyslog(LOG_ERR, "recv() fails: %m");
return 0;
}
continue;
}
#else /* Overlapped I/O used on non-blocking sockets on Windows NT */
ret = ReadFile((HANDLE)sockfd, (char *)&reqpkt, sizeof(reqpkt),
NULL, (LPOVERLAPPED)&overlap);
if ((ret == FALSE) && (GetLastError() != ERROR_IO_PENDING)) {
msyslog(LOG_ERR, "ReadFile() fails: %m");
return 0;
}
dwWait = WaitForSingleObject(hReadWriteEvent, (DWORD) TIMEOUT_SEC * 1000);
if ((dwWait == WAIT_FAILED) || (dwWait == WAIT_TIMEOUT)) {
if (dwWait == WAIT_FAILED) {
msyslog(LOG_ERR, "WaitForSingleObject for ReadFile fails: %m");
return 0;
}
continue;
}
if (!GetOverlappedResult((HANDLE)sockfd, (LPOVERLAPPED)&overlap,
(LPDWORD)&NumberOfBytesRead, FALSE)) {
msyslog(LOG_ERR, "GetOverlappedResult fails: %m");
return 0;
}
n = NumberOfBytesRead;
#endif /* SYS_WINNT */
/*
* Got one. Check through to make sure it is what
* we expect.
*/
if (n < RESP_HEADER_SIZE) {
msyslog(LOG_ERR, "received runt response (%d octets)",
n);
continue;
}
if (!ISRESPONSE(reqpkt.rm_vn_mode)) {
#ifdef DEBUG
if (debug > 1)
msyslog(LOG_INFO, "received non-response packet");
#endif
continue;
}
if (ISMORE(reqpkt.rm_vn_mode)) {
#ifdef DEBUG
if (debug > 1)
msyslog(LOG_INFO, "received fragmented packet");
#endif
continue;
}
if ( ( (INFO_VERSION(reqpkt.rm_vn_mode) < 2)
|| (INFO_VERSION(reqpkt.rm_vn_mode) > NTP_VERSION))
|| INFO_MODE(reqpkt.rm_vn_mode) != MODE_PRIVATE) {
#ifdef DEBUG
if (debug > 1)
msyslog(LOG_INFO,
"version (%d/%d) or mode (%d/%d) incorrect",
INFO_VERSION(reqpkt.rm_vn_mode),
NTP_VERSION,
INFO_MODE(reqpkt.rm_vn_mode),
MODE_PRIVATE);
#endif
continue;
}
if (INFO_SEQ(reqpkt.auth_seq) != 0) {
#ifdef DEBUG
if (debug > 1)
msyslog(LOG_INFO,
"nonzero sequence number (%d)",
INFO_SEQ(reqpkt.auth_seq));
#endif
continue;
}
if (reqpkt.implementation != IMPL_XNTPD ||
reqpkt.request != REQ_CONFIG) {
#ifdef DEBUG
if (debug > 1)
msyslog(LOG_INFO,
"implementation (%d) or request (%d) incorrect",
reqpkt.implementation, reqpkt.request);
#endif
continue;
}
if (INFO_NITEMS(reqpkt.err_nitems) != 0 ||
INFO_MBZ(reqpkt.mbz_itemsize) != 0 ||
INFO_ITEMSIZE(reqpkt.mbz_itemsize) != 0) {
#ifdef DEBUG
if (debug > 1)
msyslog(LOG_INFO,
"nitems (%d) mbz (%d) or itemsize (%d) nonzero",
INFO_NITEMS(reqpkt.err_nitems),
INFO_MBZ(reqpkt.mbz_itemsize),
INFO_ITEMSIZE(reqpkt.mbz_itemsize));
#endif
continue;
}
n = INFO_ERR(reqpkt.err_nitems);
switch (n) {
case INFO_OKAY:
/* success */
return 1;
case INFO_ERR_NODATA:
/*
* newpeer() refused duplicate association, no
* point in retrying so call it success.
*/
return 1;
case INFO_ERR_IMPL:
msyslog(LOG_ERR,
"ntp_intres.request: implementation mismatch");
return 0;
case INFO_ERR_REQ:
msyslog(LOG_ERR,
"ntp_intres.request: request unknown");
return 0;
case INFO_ERR_FMT:
msyslog(LOG_ERR,
"ntp_intres.request: format error");
return 0;
case INFO_ERR_AUTH:
msyslog(LOG_ERR,
"ntp_intres.request: permission denied");
return 0;
default:
msyslog(LOG_ERR,
"ntp_intres.request: unknown error code %d", n);
return 0;
}
}
}
