""

Makefile

@@ -65,11 +65,9 @@ tags :
 	etags *.c *.h
 
 depend: $(SRCS)
-	$(CPP) -MM $(SRCS) > depend
+	$(CPP) $(CFLAGS)  -MM $(SRCS) > depend
 
 nodepend:
 	rm -f depend
-
+        
 include depend
- 
-

iftop.8

@@ -11,7 +11,7 @@ iftop - display bandwidth usage on an interface by host
 
 .SH SYNOPSIS
 \fBiftop\fP \fB-h\fP |
-[\fB-d\fP] [\fB-p\fP] [\fB-i\fP \fIinterface\fP] [\fB-f\fP \fIfilter code\fP]
+[\fB-d\fP] [\fB-p\fP] [\fB-i\fP \fIinterface\fP] [\fB-f\fP \fIfilter code\fP] [\fB-n\fP \fInet\fP/\fImask\fP]
 
 .SH DESCRIPTION
 \fBiftop\fP listens to network traffic on a named \fIinterface\fP, or \fBeth0\fP
@@ -68,7 +68,7 @@ Listen to packets on \fIinterface\fP.
 Use \fIfilter code\fP to select the packets to count. Only IP packets are ever
 counted, so the specified code is evaluated as \fB(\fP\fIfilter code\fP\fB) and ip\fP.
 .TP
-\fB-n\fP \fInet/mask\fP
+\fB-n\fP \fInet\fP/\fImask\fP
 Specifies a network for traffic analysis.  If specified, iftop will only
 include packets flowing in to or out of the given network, and packet direction
 is determined relative to the network boundary, rather than to the interface.

iftop.c

@@ -15,6 +15,7 @@
 #include <curses.h>
 #include <signal.h>
 #include <string.h>
+#include <unistd.h>
 
 #include "iftop.h"
 #include "addr_hash.h"

options.c

@@ -7,6 +7,7 @@
 #include <stdlib.h>
 #include <unistd.h>
 #include <stdio.h>
+#include <stdint.h>
 #include <string.h>
 #include "options.h"
 
@@ -35,18 +36,27 @@ void die(char *msg) {
 void set_net_filter(char* arg) {
     char* mask;
 
-    mask = strstr(arg, "/");
-    if(mask == NULL) {
+    mask = strchr(arg, '/');
+    if (mask == NULL) {
         die("Could not parse net/mask\n");
     }
     *mask = '\0';
     mask++;
-    if(inet_aton(arg, &options.netfilternet) == 0) {
+    if (inet_aton(arg, &options.netfilternet) == 0)
         die("Invalid network address\n");
-    }
-    if(inet_aton(mask, &options.netfiltermask) == 0) {
-        die("Invalid network mask\n");
-    }
+    /* Accept a netmask like /24 or /255.255.255.0. */
+    if (!mask[strspn(mask, "0123456789")]) {
+        int n;
+        n = atoi(mask);
+        if (n > 32)
+            die("Invalid netmask");
+        else {
+            uint32_t mm = 0xffffffffl;
+            mm >>= n;
+            options.netfiltermask.s_addr = htonl(~mm);
+        }
+    } else if (inet_aton(mask, &options.netfiltermask) == 0)
+        die("Invalid netmask\n");
 
     options.netfilter = 1;
 
@@ -58,7 +68,7 @@ void usage(FILE *fp) {
     fprintf(fp,
 "iftop: display bandwidth usage on an interface by host\n"
 "\n"
-"Synopsis: iftop -h | [-d] [-p] [-i interface] [-f filter code]\n"
+"Synopsis: iftop -h | [-d] [-p] [-i interface] [-f filter code] [-n net/mask]\n"
 "\n"
 "   -h                  display this message\n"
 "   -d                  don't do hostname lookups\n"
@@ -69,7 +79,7 @@ void usage(FILE *fp) {
 "                       (default: none, but only IP packets are counted)\n"
 "   -n network/netmask  show traffic flows in/out of network\n"
 "\n"
-"iftop, version " IFTOP_VERSION "copyright (c) 2002 Paul Warren <pdw@ex-parrot.com>\n"
+"iftop, version " IFTOP_VERSION " copyright (c) 2002 Paul Warren <pdw@ex-parrot.com>\n"
             );
 }