bin/60368: performance problem /usr/sbin/ppp

[D. Rock]

>Number:         60368
>Category:       bin
>Synopsis:       performance problem /usr/sbin/ppp
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          change-request
>Submitter-Id:   current-users
>Arrival-Date:   Thu Dec 18 07:20:15 PST 2003
>Closed-Date:
>Last-Modified:
>Originator:     D. Rock
>Release:        FreeBSD 5.2-CURRENT i386
>Organization:
>Environment:
System: FreeBSD gate.rock.net 5.2-CURRENT FreeBSD 5.2-CURRENT #832: Mon Dec 8 10:46:30 CET 2003 root at gate.rock.net:/export/common/src/sys/i386/compile/ROCK i386
>Description:
With filtering rules active user-PPP (/usr/sbin/ppp) consumes high CPU load
while filtering packets.
Caused by calling getprotobynumber() for each packet filtered, regardless
if there will be any logging output or not.
>How-To-Repeat:
Define filtering rules in your /etc/ppp/ppp.conf
do some performance tests on the PPP link
>Fix:
see patch below

--- ppp.diff begins here ---
Index: usr.sbin/ppp/ip.c
===================================================================
RCS file: /export/cvs/src/usr.sbin/ppp/ip.c,v
retrieving revision 1.100
diff -u -r1.100 ip.c
--- usr.sbin/ppp/ip.c	26 Mar 2003 02:27:32 -0000	1.100
+++ usr.sbin/ppp/ip.c	11 Dec 2003 22:20:27 -0000
@@ -161,6 +161,18 @@
   }
 }
 
+static char *toprototxt(int cproto)
+{
+  static char prototxt[16];
+  struct protoent *pe;
+
+  if ((pe = getprotobynumber(cproto)) == NULL)
+    snprintf(prototxt, sizeof prototxt, "%d", cproto);
+  else
+    snprintf(prototxt, sizeof prototxt, "%s", pe->p_name);
+  return prototxt;
+}
+
 /*
  * Check a packet against the given filter
  * Returns 0 to accept the packet, non-zero to drop the packet.
@@ -187,8 +199,7 @@
   int match;			/* true if condition matched */
   int mindata;			/* minimum data size or zero */
   const struct filterent *fp = filter->rule;
-  char dbuff[100], dstip[16], prototxt[16];
-  struct protoent *pe;
+  char dbuff[100], dstip[16];
   struct ncpaddr srcaddr, dstaddr;
   const char *payload;		/* IP payload */
   int datalen;			/* IP datagram length */
@@ -239,10 +250,6 @@
     cproto = pip->ip_p;
   }
 
-  if ((pe = getprotobynumber(cproto)) == NULL)
-    snprintf(prototxt, sizeof prototxt, "%d", cproto);
-  else
-    snprintf(prototxt, sizeof prototxt, "%s", pe->p_name);
   gotinfo = estab = syn = finrst = didname = 0;
   sport = dport = 0;
 
@@ -356,7 +363,7 @@
 
           if (datalen < mindata) {
             log_Printf(LogFILTER, " error: proto %s must be at least"
-                       " %d octets\n", prototxt, mindata);
+                       " %d octets\n", toprototxt(cproto), mindata);
             return 1;
           }
 
@@ -367,7 +374,8 @@
                        ", estab = %d, syn = %d, finrst = %d",
                        estab, syn, finrst);
             }
-            log_Printf(LogDEBUG, " Filter: proto = %s, %s\n", prototxt, dbuff);
+            log_Printf(LogDEBUG, " Filter: proto = %s, %s\n",
+                       toprototxt(cproto), dbuff);
           }
           gotinfo = 1;
         }
@@ -424,7 +432,8 @@
             if (log_IsKept(LogFILTER)) {
               snprintf(dstip, sizeof dstip, "%s", ncpaddr_ntoa(&dstaddr));
               log_Printf(LogFILTER, "%sbound rule = %d accept %s "
-                         "src = %s:%d dst = %s:%d\n", filter->name, n, prototxt,
+                         "src = %s:%d dst = %s:%d\n", filter->name, n,
+                         toprototxt(cproto),
                          ncpaddr_ntoa(&srcaddr), sport, dstip, dport);
             }
           }
@@ -434,7 +443,7 @@
             snprintf(dstip, sizeof dstip, "%s", ncpaddr_ntoa(&dstaddr));
             log_Printf(LogFILTER,
                        "%sbound rule = %d deny %s src = %s/%d dst = %s/%d\n",
-                       filter->name, n, prototxt,
+                       filter->name, n, toprototxt(cproto),
                        ncpaddr_ntoa(&srcaddr), sport, dstip, dport);
           }
           return 1;
@@ -450,7 +459,7 @@
     snprintf(dstip, sizeof dstip, "%s", ncpaddr_ntoa(&dstaddr));
     log_Printf(LogFILTER,
                "%sbound rule = implicit deny %s src = %s/%d dst = %s/%d\n",
-               filter->name, prototxt, ncpaddr_ntoa(&srcaddr), sport,
+               filter->name, toprototxt(cproto), ncpaddr_ntoa(&srcaddr), sport,
                dstip, dport);
   }
 
--- ppp.diff ends here ---


>Release-Note:
>Audit-Trail:
>Unformatted: