Print NTP refid as hexadecimal number.

In NTPv4 (RFC 5905) the refid field for stratum > 1 is an IPv4 address
or first 32 bits of MD5 sum of an IPv6 address. It's not possible to
tell which of the two it actually is. Print the field as a hexadecimal
number in order to not confuse refids generated from IPv6 addresses with
IPv4 addresses.

diff --git a/print-ntp.c b/print-ntp.c
index 1593ca6bdb061d536f554d3d0d748e0d1507d91c..63e69d5c2cfcae5b5d8b63595d903ab23df46520 100644 (file)
--- a/print-ntp.c
+++ b/print-ntp.c
@@ -279,7 +279,9 @@ ntp_print(netdissect_options *ndo,
                return;
 
        default:
-               ND_PRINT((ndo, "%s", ipaddr_string(ndo, &(bp->refid))));
+               /* In NTPv4 (RFC 5905) refid is an IPv4 address or first 32 bits of
+                  MD5 sum of IPv6 address */
+               ND_PRINT((ndo, "%08x", EXTRACT_32BITS(&bp->refid)));
                break;
        }