From 6edbe8452cc4a5eb0e5cd6aa92039bb17d8fc9ef Mon Sep 17 00:00:00 2001
From: Evan Hunt <each@isc.org>
Date: Sun, 8 May 2022 17:17:29 -0700
Subject: [PATCH] Add lower bound checks to fetchlimit test

Check that the recursing client count is above a reasonable
minimum, as well as below a maximum, so that we can detect
bugs that cause recursion to fail too early or too often.

(cherry picked from commit 8834c44683f76b3e9fff795eb3d9ec52bc063b6a)
Conflict: NA
Reference: https://gitlab.isc.org/isc-projects/bind9/-/commit/6edbe8452cc4a5eb0e5cd6aa92039bb17d8fc9ef
---
 bin/tests/system/fetchlimit/tests.sh | 41 +++++++++++++++-------------
 1 file changed, 22 insertions(+), 19 deletions(-)

diff --git a/bin/tests/system/fetchlimit/tests.sh b/bin/tests/system/fetchlimit/tests.sh
index e7df552af0..55f4bf6a48 100644
--- a/bin/tests/system/fetchlimit/tests.sh
+++ b/bin/tests/system/fetchlimit/tests.sh
@@ -21,7 +21,7 @@ burst() {
     num=${3:-20}
     rm -f burst.input.$$
     while [ $num -gt 0 ]; do
-        num=`expr $num - 1`
+        num=$((num-1))
         echo "${num}${1}${2}.lamesub.example A" >> burst.input.$$
     done
     $PERL ../ditch.pl -p ${PORT} -s 10.53.0.3 burst.input.$$
@@ -33,7 +33,9 @@ stat() {
             sed 's;.*: \([^/][^/]*\)/.*;\1;'`
     echo_i "clients: $clients"
     [ "$clients" = "" ] && return 1
-    [ "$clients" -le $1 ]
+    [ "$clients" -ge $1 ] || return 1
+    [ "$clients" -le $2 ] || return 1
+    return 0
 }
 
 status=0
@@ -47,13 +49,14 @@ for try in 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20; do
     burst a $try
     # fetches-per-server is at 400, but at 20qps against a lame server,
     # we'll reach 200 at the tenth second, and the quota should have been
-    # tuned to less than that by then
-    stat 200 || ret=1
+    # tuned to less than that by then.
+    [ $try -le 5 ] && low=$((try*10))
+    stat 20 200 || ret=1
     [ $ret -eq 1 ] && break
     sleep 1
 done
 if [ $ret != 0 ]; then echo_i "failed"; fi
-status=`expr $status + $ret`
+status=$((status+ret))
 
 echo_i "dumping ADB data"
 $RNDCCMD dumpdb -adb
@@ -77,14 +80,14 @@ fails=`grep 'queries resulted in SERVFAIL' ns3/named.stats | sed 's/\([0-9][0-9]
 [ -z "$fails" ] && fails=0
 [ "$fails" -ge "$sspill" ] || ret=1
 if [ $ret != 0 ]; then echo_i "failed"; fi
-status=`expr $status + $ret`
+status=$((status+ret))
 
 echo_i "checking lame server recovery"
 ret=0
 rm -f ans4/norespond
 for try in 1 2 3 4 5; do
     burst b $try
-    stat 200 || ret=1
+    stat 0 200 || ret=1
     [ $ret -eq 1 ] && break
     sleep 1
 done
@@ -99,7 +102,7 @@ quota=$5
 
 for try in 1 2 3 4 5 6 7 8 9 10; do
     burst c $try
-    stat 20 || ret=1
+    stat 0 20 || ret=1
     [ $ret -eq 1 ] && break
     sleep 1
 done
@@ -112,7 +115,7 @@ set -- $info
 [ ${5:-${quota}} -gt $quota ] || ret=1
 quota=$5
 if [ $ret != 0 ]; then echo_i "failed"; fi
-status=`expr $status + $ret`
+status=$((status+ret))
 
 copy_setports ns3/named2.conf.in ns3/named.conf
 rndc_reconfig ns3 10.53.0.3
@@ -126,17 +129,17 @@ for try in 1 2 3 4 5; do
     burst b $try 300
     $DIGCMD a ${try}.example > dig.out.ns3.$try
     grep "status: NOERROR" dig.out.ns3.$try > /dev/null 2>&1 && \
-            success=`expr $success + 1`
+            success=$((success+1))
     grep "status: SERVFAIL" dig.out.ns3.$try > /dev/null 2>&1 && \
-            fail=`expr $fail + 1`
-    stat 50 || ret=1
+            fail=$(($fail+1))
+    stat 30 50 || ret=1
     [ $ret -eq 1 ] && break
     $RNDCCMD recursing 2>&1 | sed 's/^/ns3 /' | cat_i
     sleep 1
 done
 echo_i "$success successful valid queries, $fail SERVFAIL"
 if [ $ret != 0 ]; then echo_i "failed"; fi
-status=`expr $status + $ret`
+status=$((status+ret))
 
 echo_i "checking drop statistics"
 rm -f ns3/named.stats
@@ -151,7 +154,7 @@ drops=`grep 'queries dropped' ns3/named.stats | sed 's/\([0-9][0-9]*\) queries.*
 [ -z "$drops" ] && drops=0
 [ "$drops" -ge "$zspill" ] || ret=1
 if [ $ret != 0 ]; then echo_i "failed"; fi
-status=`expr $status + $ret`
+status=$((status+ret))
 
 copy_setports ns3/named3.conf.in ns3/named.conf
 rndc_reconfig ns3 10.53.0.3
@@ -165,11 +168,11 @@ touch ans4/norespond
 for try in 1 2 3 4 5; do
     burst b $try 400
     $DIGCMD +time=2 a ${try}.example > dig.out.ns3.$try
-    stat 400 || exceeded=`expr $exceeded + 1`
+    stat 100 400 || exceeded=$((exceeded + 1))
     grep "status: NOERROR" dig.out.ns3.$try > /dev/null 2>&1 && \
-            success=`expr $success + 1`
+            success=$((success+1))
     grep "status: SERVFAIL" dig.out.ns3.$try > /dev/null 2>&1 && \
-            fail=`expr $fail + 1`
+            fail=$(($fail+1))
     sleep 1
 done
 echo_i "$success successful valid queries (expected 5)"
@@ -179,7 +182,7 @@ echo_i "$fail SERVFAIL responses (expected 0)"
 echo_i "clients count exceeded 400 on $exceeded trials (expected 0)"
 [ "$exceeded" -eq 0 ] || { echo_i "failed"; ret=1; }
 if [ $ret != 0 ]; then echo_i "failed"; fi
-status=`expr $status + $ret`
+status=$((status+ret))
 
 echo_i "checking drop statistics"
 rm -f ns3/named.stats
@@ -191,7 +194,7 @@ done
 drops=`grep 'queries dropped due to recursive client limit' ns3/named.stats | sed 's/\([0-9][0-9]*\) queries.*/\1/'`
 [ "${drops:-0}" -ne 0 ] || ret=1
 if [ $ret != 0 ]; then echo_i "failed"; fi
-status=`expr $status + $ret`
+status=$((status+ret))
 
 echo_i "exit status: $status"
 [ $status -eq 0 ] || exit 1
-- 
2.23.0

