1 files changed, 353 insertions, 0 deletions

diff --git a/usr.sbin/timed/timed/measure.c b/usr.sbin/timed/timed/measure.c
new file mode 100644
index 0000000..4066d10
--- /dev/null
+++ b/usr.sbin/timed/timed/measure.c
@@ -0,0 +1,353 @@
+/*-
+ * Copyright (c) 1985, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef lint
+static char sccsid[] = "@(#)measure.c	8.1 (Berkeley) 6/6/93";
+#endif /* not lint */
+
+#ifdef sgi
+#ident "$Revision: 1.8 $"
+#endif
+
+#include "globals.h"
+#include <netinet/in_systm.h>
+#include <netinet/ip.h>
+#include <netinet/ip_icmp.h>
+
+#define MSEC_DAY	(SECDAY*1000)
+
+#define PACKET_IN	1024
+
+#define MSGS		5		/* timestamps to average */
+#define TRIALS		10		/* max # of timestamps sent */
+
+extern int sock_raw;
+
+int measure_delta;
+
+static n_short seqno = 0;
+
+/*
+ * Measures the differences between machines' clocks using
+ * ICMP timestamp messages.
+ */
+int					/* status val defined in globals.h */
+measure(maxmsec, wmsec, hname, addr, print)
+	u_long maxmsec;			/* wait this many msec at most */
+	u_long wmsec;			/* msec to wait for an answer */
+	char *hname;
+	struct sockaddr_in *addr;
+	int print;			/* print complaints on stderr */
+{
+	int length;
+	int measure_status;
+	int rcvcount, trials;
+	int cc, count;
+	fd_set ready;
+	long sendtime, recvtime, histime1, histime2;
+	long idelta, odelta, total;
+	long min_idelta, min_odelta;
+	struct timeval tdone, tcur, ttrans, twait, tout;
+	u_char packet[PACKET_IN], opacket[64];
+	register struct icmp *icp = (struct icmp *) packet;
+	register struct icmp *oicp = (struct icmp *) opacket;
+	struct ip *ip = (struct ip *) packet;
+
+	min_idelta = min_odelta = 0x7fffffff;
+	measure_status = HOSTDOWN;
+	measure_delta = HOSTDOWN;
+	errno = 0;
+
+	/* open raw socket used to measure time differences */
+	if (sock_raw < 0) {
+		sock_raw = socket(AF_INET, SOCK_RAW, IPPROTO_ICMP);
+		if (sock_raw < 0)  {
+			syslog(LOG_ERR, "opening raw socket: %m");
+			goto quit;
+		}
+	}
+	    
+
+	/*
+	 * empty the icmp input queue
+	 */
+	FD_ZERO(&ready);
+	for (;;) {
+		tout.tv_sec = tout.tv_usec = 0;
+		FD_SET(sock_raw, &ready);
+		if (select(sock_raw+1, &ready, 0,0, &tout)) {
+			length = sizeof(struct sockaddr_in);
+			cc = recvfrom(sock_raw, (char *)packet, PACKET_IN, 0,
+				      0,&length);
+			if (cc < 0)
+				goto quit;
+			continue;
+		}
+		break;
+	}
+
+	/*
+	 * Choose the smallest transmission time in each of the two
+	 * directions. Use these two latter quantities to compute the delta
+	 * between the two clocks.
+	 */
+
+	oicp->icmp_type = ICMP_TSTAMP;
+	oicp->icmp_code = 0;
+	oicp->icmp_id = getpid();
+	oicp->icmp_rtime = 0;
+	oicp->icmp_ttime = 0;
+	oicp->icmp_seq = seqno;
+
+	FD_ZERO(&ready);
+
+#ifdef sgi
+	sginap(1);			/* start at a clock tick */
+#endif /* sgi */
+
+	(void)gettimeofday(&tdone, 0);
+	mstotvround(&tout, maxmsec);
+	timevaladd(&tdone, &tout);		/* when we give up */
+
+	mstotvround(&twait, wmsec);
+
+	rcvcount = 0;
+	trials = 0;
+	while (rcvcount < MSGS) {
+		(void)gettimeofday(&tcur, 0);
+
+		/*
+		 * keep sending until we have sent the max
+		 */
+		if (trials < TRIALS) {
+			trials++;
+			oicp->icmp_otime = ((tcur.tv_sec % SECDAY) * 1000
+					    + tcur.tv_usec / 1000);
+			oicp->icmp_cksum = 0;
+			oicp->icmp_cksum = in_cksum((u_short*)oicp,
+						    sizeof(*oicp));
+
+			count = sendto(sock_raw, opacket, sizeof(*oicp), 0,
+				       (struct sockaddr*)addr,
+				       sizeof(struct sockaddr));
+			if (count < 0) {
+				if (measure_status == HOSTDOWN)
+					measure_status = UNREACHABLE;
+				goto quit;
+			}
+			++oicp->icmp_seq;
+
+			ttrans = tcur;
+			timevaladd(&ttrans, &twait);
+		} else {
+			ttrans = tdone;
+		}
+
+		while (rcvcount < trials) {
+			timevalsub(&tout, &ttrans, &tcur);
+			if (tout.tv_sec < 0)
+				tout.tv_sec = 0;
+
+			FD_SET(sock_raw, &ready);
+			count = select(sock_raw+1, &ready, (fd_set *)0,
+				       (fd_set *)0, &tout);
+			(void)gettimeofday(&tcur, (struct timezone *)0);
+			if (count <= 0)
+				break;
+
+			length = sizeof(struct sockaddr_in);
+			cc = recvfrom(sock_raw, (char *)packet, PACKET_IN, 0,
+				      0,&length);
+			if (cc < 0)
+				goto quit;
+
+			/* 
+			 * got something.  See if it is ours
+			 */
+			icp = (struct icmp *)(packet + (ip->ip_hl << 2));
+			if (cc < sizeof(*ip)
+			    || icp->icmp_type != ICMP_TSTAMPREPLY
+			    || icp->icmp_id != oicp->icmp_id
+			    || icp->icmp_seq < seqno
+			    || icp->icmp_seq >= oicp->icmp_seq)
+				continue;
+
+
+			sendtime = ntohl(icp->icmp_otime);
+			recvtime = ((tcur.tv_sec % SECDAY) * 1000 +
+				    tcur.tv_usec / 1000);
+
+			total = recvtime-sendtime;
+			if (total < 0)	/* do not hassle midnight */
+				continue;
+
+			rcvcount++;
+			histime1 = ntohl(icp->icmp_rtime);
+			histime2 = ntohl(icp->icmp_ttime);
+			/*
+			 * a host using a time format different from
+			 * msec. since midnight UT (as per RFC792) should
+			 * set the high order bit of the 32-bit time
+			 * value it transmits.
+			 */
+			if ((histime1 & 0x80000000) != 0) {
+				measure_status = NONSTDTIME;
+				goto quit;
+			}
+			measure_status = GOOD;
+
+			idelta = recvtime-histime2;
+			odelta = histime1-sendtime;
+
+			/* do not be confused by midnight */
+			if (idelta < -MSEC_DAY/2) idelta += MSEC_DAY;
+			else if (idelta > MSEC_DAY/2) idelta -= MSEC_DAY;
+
+			if (odelta < -MSEC_DAY/2) odelta += MSEC_DAY;
+			else if (odelta > MSEC_DAY/2) odelta -= MSEC_DAY;
+
+			/* save the quantization error so that we can get a
+			 * measurement finer than our system clock.
+			 */
+			if (total < MIN_ROUND) {
+				measure_delta = (odelta - idelta)/2;
+				goto quit;
+			}
+
+			if (idelta < min_idelta)
+				min_idelta = idelta;
+			if (odelta < min_odelta)
+				min_odelta = odelta;
+
+			measure_delta = (min_odelta - min_idelta)/2;
+		}
+
+		if (tcur.tv_sec > tdone.tv_sec
+		    || (tcur.tv_sec == tdone.tv_sec
+			&& tcur.tv_usec >= tdone.tv_usec))
+			break;
+	}
+
+quit:
+	seqno += TRIALS;		/* allocate our sequence numbers */
+
+	/*
+	 * If no answer is received for TRIALS consecutive times,
+	 * the machine is assumed to be down
+	 */
+	if (measure_status == GOOD) {
+		if (trace) {
+			fprintf(fd,
+				"measured delta %4d, %d trials to %-15s %s\n",
+			   	measure_delta, trials,
+				inet_ntoa(addr->sin_addr), hname);
+		}
+	} else if (print) {
+		if (errno != 0)
+			fprintf(stderr, "measure %s: %s\n", hname,
+				strerror(errno));
+	} else {
+		if (errno != 0) {
+			syslog(LOG_ERR, "measure %s: %m", hname);
+		} else {
+			syslog(LOG_ERR, "measure: %s did not respond", hname);
+		}
+		if (trace) {
+			fprintf(fd,
+				"measure: %s failed after %d trials\n",
+				hname, trials);
+			(void)fflush(fd);
+		}
+	}
+
+	return(measure_status);
+}
+
+
+
+
+
+/*
+ * round a number of milliseconds into a struct timeval
+ */
+void
+mstotvround(res, x)
+	struct timeval *res;
+	long x;
+{
+#ifndef sgi
+	if (x < 0)
+		x = -((-x + 3)/5);
+	else
+		x = (x+3)/5;
+	x *= 5;
+#endif /* sgi */
+	res->tv_sec = x/1000;
+	res->tv_usec = (x-res->tv_sec*1000)*1000;
+	if (res->tv_usec < 0) {
+		res->tv_usec += 1000000;
+		res->tv_sec--;
+	}
+}
+
+void
+timevaladd(tv1, tv2)
+	struct timeval *tv1, *tv2;
+{
+	tv1->tv_sec += tv2->tv_sec;
+	tv1->tv_usec += tv2->tv_usec;
+	if (tv1->tv_usec >= 1000000) {
+		tv1->tv_sec++;
+		tv1->tv_usec -= 1000000;
+	}
+	if (tv1->tv_usec < 0) {
+		tv1->tv_sec--;
+		tv1->tv_usec += 1000000;
+	}
+}
+
+void
+timevalsub(res, tv1, tv2)
+	struct timeval *res, *tv1, *tv2;
+{
+	res->tv_sec = tv1->tv_sec - tv2->tv_sec;
+	res->tv_usec = tv1->tv_usec - tv2->tv_usec;
+	if (res->tv_usec >= 1000000) {
+		res->tv_sec++;
+		res->tv_usec -= 1000000;
+	}
+	if (res->tv_usec < 0) {
+		res->tv_sec--;
+		res->tv_usec += 1000000;
+	}
+}