netdev - [PATCH] iputils ping,ping6: use monotonic clock to schedule pings

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <alpine.DEB.1.10.1009051453090.13886@red.crap.retrofitta.se>
Date:	Sun, 5 Sep 2010 14:58:24 +0200 (CEST)
From:	Thomas Habets <thomas@...ets.pp.se>
To:	netdev@...r.kernel.org
Subject: [PATCH] iputils ping,ping6: use monotonic clock to schedule pings


This fixes the problem where when time is set backwards 'ping' appears
to freeze until the walltime catches up with the previously set time.

Adds dependency on librt.

diff --git a/Makefile b/Makefile
index 42f8475..a6812a3 100644
--- a/Makefile
+++ b/Makefile
@@ -28,8 +28,8 @@ all: $(TARGETS)

  tftpd: tftpd.o tftpsubs.o
  arping: arping.o -lsysfs
-ping: ping.o ping_common.o
-ping6: ping6.o ping_common.o -lresolv -lcrypto
+ping: ping.o ping_common.o -lrt
+ping6: ping6.o ping_common.o -lresolv -lcrypto -lrt
  ping.o ping6.o ping_common.o: ping_common.h
  tftpd.o tftpsubs.o: tftp.h

diff --git a/ping_common.c b/ping_common.c
index e0edf39..5883e63 100644
--- a/ping_common.c
+++ b/ping_common.c
@@ -304,6 +304,20 @@ void print_timestamp(void)
         }
  }

+int
+getclock(struct timeval *tv)
+{
+#ifdef CLOCK_MONOTONIC
+       struct timespec ts;
+       if (!clock_gettime(CLOCK_MONOTONIC, &ts)) {
+               tv->tv_sec = ts.tv_sec;
+               tv->tv_usec = ts.tv_nsec / 1000;
+               return;
+       }
+#endif
+       return gettimeofday(tv, NULL);
+}
+
  /*
   * pinger --
   *     Compose and transmit an ICMP ECHO REQUEST packet.  The IP packet
@@ -324,13 +338,13 @@ int pinger(void)

         /* Check that packets < rate*time + preload */
         if (cur_time.tv_sec == 0) {
-               gettimeofday(&cur_time, NULL);
+               getclock(&cur_time);
                 tokens = interval*(preload-1);
         } else {
                 long ntokens;
                 struct timeval tv;

-               gettimeofday(&tv, NULL);
+               getclock(&tv);
                 ntokens = (tv.tv_sec - cur_time.tv_sec)*1000 +
                         (tv.tv_usec-cur_time.tv_usec)/1000;
                 if (!interval) {
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html