/* Output a long floating point value in hex in the style described above
*/
void
l_fp_output(
l_fp * ts,
FILE * output
)
{
fprintf(output, "%s\n", prettydate(ts));
}
/*
* wwvb_timer - called once per second by the transmit procedure
*/
static void
wwvb_timer(
int unit,
struct peer *peer
)
{
register struct wwvbunit *up;
struct refclockproc *pp;
char pollchar; /* character sent to clock */
#ifdef DEBUG
l_fp now;
#endif
/*
* Time to poll the clock. The Spectracom clock responds to a
* 'T' by returning a timecode in the format(s) specified above.
* Note there is no checking on state, since this may not be the
* only customer reading the clock. Only one customer need poll
* the clock; all others just listen in.
*/
pp = peer->procptr;
up = pp->unitptr;
if (up->linect > 0)
pollchar = 'R';
else
pollchar = 'T';
if (write(pp->io.fd, &pollchar, 1) != 1)
refclock_report(peer, CEVNT_FAULT);
#ifdef DEBUG
get_systime(&now);
if (debug)
printf("%c poll at %s\n", pollchar, prettydate(&now));
#endif
#ifdef HAVE_PPSAPI
if (up->ppsapi_lit &&
refclock_pps(peer, &up->atom, pp->sloppyclockflag) > 0) {
up->pcount++,
peer->flags |= FLAG_PPS;
peer->precision = PPS_PRECISION;
}
#endif /* HAVE_PPSAPI */
}
/*
* wwvb_receive - receive data from the serial interface
*/
static void
wwvb_receive(
struct recvbuf *rbufp
)
{
struct wwvbunit *up;
struct refclockproc *pp;
struct peer *peer;
l_fp trtmp; /* arrival timestamp */
int tz; /* time zone */
int day, month; /* ddd conversion */
int temp; /* int temp */
char syncchar; /* synchronization indicator */
char qualchar; /* quality indicator */
char leapchar; /* leap indicator */
char dstchar; /* daylight/standard indicator */
char tmpchar; /* trashbin */
/*
* Initialize pointers and read the timecode and timestamp
*/
peer = rbufp->recv_peer;
pp = peer->procptr;
up = pp->unitptr;
temp = refclock_gtlin(rbufp, pp->a_lastcode, BMAX, &trtmp);
/*
* Note we get a buffer and timestamp for both a <cr> and <lf>,
* but only the <cr> timestamp is retained. Note: in format 0 on
* a Netclock/2 or upgraded 8170 the start bit is delayed 100
* +-50 us relative to the pps; however, on an unmodified 8170
* the start bit can be delayed up to 10 ms. In format 2 the
* reading precision is only to the millisecond. Thus, unless
* you have a PPS gadget and don't have to have the year, format
* 0 provides the lowest jitter.
* Save the timestamp of each <CR> in up->laststamp. Lines with
* no characters occur for every <LF>, and for some <CR>s when
* format 0 is used. Format 0 starts and ends each cycle with a
* <CR><LF> pair, format 2 starts each cycle with its only pair.
* The preceding <CR> is the on-time character for both formats.
* The timestamp provided with non-empty lines corresponds to
* the <CR> following the timecode, which is ultimately not used
* with format 0 and is used for the following timecode for
* format 2.
*/
if (temp == 0) {
if (up->prev_eol_cr) {
DPRINTF(2, ("wwvb: <LF> @ %s\n",
prettydate(&trtmp)));
} else {
up->laststamp = trtmp;
DPRINTF(2, ("wwvb: <CR> @ %s\n",
prettydate(&trtmp)));
}
up->prev_eol_cr = !up->prev_eol_cr;
return;
}
pp->lencode = temp;
pp->lastrec = up->laststamp;
up->laststamp = trtmp;
up->prev_eol_cr = TRUE;
DPRINTF(2, ("wwvb: code @ %s\n"
" using %s minus one char\n",
prettydate(&trtmp), prettydate(&pp->lastrec)));
if (L_ISZERO(&pp->lastrec))
return;
/*
* We get down to business, check the timecode format and decode
* its contents. This code uses the timecode length to determine
* format 0, 2 or 3. If the timecode has invalid length or is
* not in proper format, we declare bad format and exit.
*/
syncchar = qualchar = leapchar = dstchar = ' ';
tz = 0;
switch (pp->lencode) {
case LENWWVB0:
/*
* Timecode format 0: "I ddd hh:mm:ss DTZ=nn"
*/
if (sscanf(pp->a_lastcode,
"%c %3d %2d:%2d:%2d%c%cTZ=%2d",
&syncchar, &pp->day, &pp->hour, &pp->minute,
&pp->second, &tmpchar, &dstchar, &tz) == 8) {
pp->nsec = 0;
break;
}
goto bad_format;
case LENWWVB2:
/*
* Timecode format 2: "IQyy ddd hh:mm:ss.mmm LD" */
if (sscanf(pp->a_lastcode,
"%c%c %2d %3d %2d:%2d:%2d.%3ld %c",
&syncchar, &qualchar, &pp->year, &pp->day,
&pp->hour, &pp->minute, &pp->second, &pp->nsec,
&leapchar) == 9) {
pp->nsec *= 1000000;
break;
}
goto bad_format;
case LENWWVB3:
/*
* Timecode format 3: "0003I yyyymmdd hhmmss+0000SL#"
* WARNING: Undocumented, and the on-time character # is
* not yet handled correctly by this driver. It may be
* as simple as compensating for an additional 1/960 s.
*/
if (sscanf(pp->a_lastcode,
"0003%c %4d%2d%2d %2d%2d%2d+0000%c%c",
&syncchar, &pp->year, &month, &day, &pp->hour,
&pp->minute, &pp->second, &dstchar, &leapchar) == 8)
{
pp->day = ymd2yd(pp->year, month, day);
pp->nsec = 0;
break;
}
goto bad_format;
default:
bad_format:
/*
* Unknown format: If dumping internal table, record
* stats; otherwise, declare bad format.
*/
if (up->linect > 0) {
up->linect--;
record_clock_stats(&peer->srcadr,
pp->a_lastcode);
} else {
refclock_report(peer, CEVNT_BADREPLY);
}
return;
}
/*
* Decode synchronization, quality and leap characters. If
* unsynchronized, set the leap bits accordingly and exit.
* Otherwise, set the leap bits according to the leap character.
* Once synchronized, the dispersion depends only on the
* quality character.
*/
switch (qualchar) {
case ' ':
pp->disp = .001;
pp->lastref = pp->lastrec;
break;
case 'A':
pp->disp = .01;
break;
case 'B':
pp->disp = .1;
break;
case 'C':
pp->disp = .5;
break;
case 'D':
pp->disp = MAXDISPERSE;
break;
default:
pp->disp = MAXDISPERSE;
refclock_report(peer, CEVNT_BADREPLY);
break;
}
if (syncchar != ' ')
pp->leap = LEAP_NOTINSYNC;
else if (leapchar == 'L')
pp->leap = LEAP_ADDSECOND;
else
pp->leap = LEAP_NOWARNING;
/*
* Process the new sample in the median filter and determine the
* timecode timestamp, but only if the PPS is not in control.
*/
#ifdef HAVE_PPSAPI
up->tcount++;
if (peer->flags & FLAG_PPS)
return;
#endif /* HAVE_PPSAPI */
if (!refclock_process_f(pp, pp->fudgetime2))
refclock_report(peer, CEVNT_BADTIME);
}
/*
** Check if it's data for us and whether it's useable or not.
**
** If not, return a failure code so we can delete this server from our list
** and continue with another one.
*/
int
process_pkt (
struct pkt *rpkt,
sockaddr_u *sender,
int pkt_len,
int mode,
struct pkt *spkt,
const char * func_name
)
{
u_int key_id;
struct key * pkt_key;
int is_authentic;
int mac_size;
u_int exten_len;
u_int32 * exten_end;
u_int32 * packet_end;
l_fp sent_xmt;
l_fp resp_org;
// key_id = 0;
pkt_key = NULL;
is_authentic = (HAVE_OPT(AUTHENTICATION)) ? 0 : -1;
/*
* Parse the extension field if present. We figure out whether
* an extension field is present by measuring the MAC size. If
* the number of words following the packet header is 0, no MAC
* is present and the packet is not authenticated. If 1, the
* packet is a crypto-NAK; if 3, the packet is authenticated
* with DES; if 5, the packet is authenticated with MD5; if 6,
* the packet is authenticated with SHA. If 2 or 4, the packet
* is a runt and discarded forthwith. If greater than 6, an
* extension field is present, so we subtract the length of the
* field and go around again.
*/
if (pkt_len < (int)LEN_PKT_NOMAC || (pkt_len & 3) != 0) {
msyslog(LOG_ERR,
"%s: Incredible packet length: %d. Discarding.",
func_name, pkt_len);
return PACKET_UNUSEABLE;
}
/* HMS: the following needs a bit of work */
/* Note: pkt_len must be a multiple of 4 at this point! */
packet_end = (void*)((char*)rpkt + pkt_len);
exten_end = skip_efields(rpkt->exten, packet_end);
if (NULL == exten_end) {
msyslog(LOG_ERR,
"%s: Missing extension field. Discarding.",
func_name);
return PACKET_UNUSEABLE;
}
/* get size of MAC in cells; can be zero */
exten_len = (u_int)(packet_end - exten_end);
/* deduce action required from remaining length */
switch (exten_len) {
case 0: /* no Legacy MAC */
break;
case 1: /* crypto NAK */
/* Only if the keyID is 0 and there were no EFs */
key_id = ntohl(*exten_end);
printf("Crypto NAK = 0x%08x from %s\n", key_id, stoa(sender));
break;
case 3: /* key ID + 3DES MAC -- unsupported! */
msyslog(LOG_ERR,
"%s: Key ID + 3DES MAC is unsupported. Discarding.",
func_name);
return PACKET_UNUSEABLE;
case 5: /* key ID + MD5 MAC */
case 6: /* key ID + SHA MAC */
/*
** Look for the key used by the server in the specified
** keyfile and if existent, fetch it or else leave the
** pointer untouched
*/
key_id = ntohl(*exten_end);
get_key(key_id, &pkt_key);
if (!pkt_key) {
printf("unrecognized key ID = 0x%08x\n", key_id);
break;
}
/*
** Seems like we've got a key with matching keyid.
**
** Generate a md5sum of the packet with the key from our
** keyfile and compare those md5sums.
*/
mac_size = exten_len << 2;
if (!auth_md5(rpkt, pkt_len - mac_size,
mac_size - 4, pkt_key)) {
is_authentic = FALSE;
break;
}
/* Yay! Things worked out! */
is_authentic = TRUE;
TRACE(1, ("sntp %s: packet from %s authenticated using key id %d.\n",
func_name, stoa(sender), key_id));
break;
default:
msyslog(LOG_ERR,
"%s: Unexpected extension length: %d. Discarding.",
func_name, exten_len);
return PACKET_UNUSEABLE;
}
switch (is_authentic) {
case -1: /* unknown */
break;
case 0: /* not authentic */
return SERVER_AUTH_FAIL;
break;
case 1: /* authentic */
break;
default: /* error */
break;
}
/* Check for server's ntp version */
if (PKT_VERSION(rpkt->li_vn_mode) < NTP_OLDVERSION ||
PKT_VERSION(rpkt->li_vn_mode) > NTP_VERSION) {
msyslog(LOG_ERR,
"%s: Packet shows wrong version (%d)",
func_name, PKT_VERSION(rpkt->li_vn_mode));
return SERVER_UNUSEABLE;
}
/* We want a server to sync with */
if (PKT_MODE(rpkt->li_vn_mode) != mode &&
PKT_MODE(rpkt->li_vn_mode) != MODE_PASSIVE) {
msyslog(LOG_ERR,
"%s: mode %d stratum %d", func_name,
PKT_MODE(rpkt->li_vn_mode), rpkt->stratum);
return SERVER_UNUSEABLE;
}
/* Stratum is unspecified (0) check what's going on */
if (STRATUM_PKT_UNSPEC == rpkt->stratum) {
char *ref_char;
TRACE(1, ("%s: Stratum unspecified, going to check for KOD (stratum: %d)\n",
func_name, rpkt->stratum));
ref_char = (char *) &rpkt->refid;
TRACE(1, ("%s: Packet refid: %c%c%c%c\n", func_name,
ref_char[0], ref_char[1], ref_char[2], ref_char[3]));
/* If it's a KOD packet we'll just use the KOD information */
if (ref_char[0] != 'X') {
if (strncmp(ref_char, "DENY", 4) == 0)
return KOD_DEMOBILIZE;
if (strncmp(ref_char, "RSTR", 4) == 0)
return KOD_DEMOBILIZE;
if (strncmp(ref_char, "RATE", 4) == 0)
return KOD_RATE;
/*
** There are other interesting kiss codes which
** might be interesting for authentication.
*/
}
}
/* If the server is not synced it's not really useable for us */
if (LEAP_NOTINSYNC == PKT_LEAP(rpkt->li_vn_mode)) {
msyslog(LOG_ERR,
"%s: %s not in sync, skipping this server",
func_name, stoa(sender));
return SERVER_UNUSEABLE;
}
/*
* Decode the org timestamp and make sure we're getting a response
* to our last request, but only if we're not in broadcast mode.
*/
if (MODE_BROADCAST == mode)
return pkt_len;
if (!L_ISEQU(&rpkt->org, &spkt->xmt)) {
NTOHL_FP(&rpkt->org, &resp_org);
NTOHL_FP(&spkt->xmt, &sent_xmt);
msyslog(LOG_ERR,
"%s response org expected to match sent xmt",
stoa(sender));
msyslog(LOG_ERR, "resp org: %s", prettydate(&resp_org));
msyslog(LOG_ERR, "sent xmt: %s", prettydate(&sent_xmt));
return PACKET_UNUSEABLE;
}
return pkt_len;
}
