From c653dd118fce60a16f0d17e983fc4693bf1287bd Mon Sep 17 00:00:00 2001 From: rpm-build Date: Mon, 20 Oct 2014 13:26:38 +0200 Subject: [PATCH 7/7] Introduce -nn option This changes the semantics on -n option so only namelookups are skipped. Port numbers *are* translated to their string representations. Option -nn then has the same semantics as -n had originally. --- addrtoname.c | 4 ++-- tcpdump.1.in | 6 +++++- 2 files changed, 7 insertions(+), 3 deletions(-) diff --git a/addrtoname.c b/addrtoname.c index 277751d..ed8376b 100644 --- a/addrtoname.c +++ b/addrtoname.c @@ -787,7 +787,7 @@ init_servarray(netdissect_options *ndo) while (table->name) table = table->nxt; - if (ndo->ndo_nflag) { + if (ndo->ndo_nflag > 1) { (void)snprintf(buf, sizeof(buf), "%d", port); table->name = strdup(buf); } else @@ -1187,7 +1187,7 @@ init_addrtoname(netdissect_options *ndo, uint32_t localnet, uint32_t mask) f_localnet = localnet; f_netmask = mask; } - if (ndo->ndo_nflag) + if (ndo->ndo_nflag > 1) /* * Simplest way to suppress names. */ diff --git a/tcpdump.1.in b/tcpdump.1.in index e3a6ef4..a8e65c2 100644 --- a/tcpdump.1.in +++ b/tcpdump.1.in @@ -532,7 +532,11 @@ Use \fIsecret\fP as a shared secret for validating the digests found in TCP segments with the TCP-MD5 option (RFC 2385), if present. .TP .B \-n -Don't convert addresses (i.e., host addresses, port numbers, etc.) to names. +Don't convert host addresses to names. This can be used to avoid +DNS lookups. +.TP +.B \-nn +Don't convert protocol and port numbers etc. to names either. .TP .B \-N Don't print domain name qualification of host names. -- 1.8.3.1