1# 2007 May 10 2# 3# The author disclaims copyright to this source code. In place of 4# a legal notice, here is a blessing: 5# 6# May you do good and not evil. 7# May you find forgiveness for yourself and forgive others. 8# May you share freely, never taking more than you give. 9# 10#*********************************************************************** 11# This file implements regression tests for SQLite library. The focus 12# of this file is checking the libraries response to subtly corrupting 13# the database file by changing the values of pseudo-randomly selected 14# bytes. 15# 16# $Id: fuzz3.test,v 1.3 2009/01/05 17:19:03 drh Exp $ 17 18set testdir [file dirname $argv0] 19source $testdir/tester.tcl 20 21 22expr srand(123) 23 24proc rstring {n} { 25 set str s 26 while {[string length $str] < $n} { 27 append str [expr rand()] 28 } 29 return [string range $str 0 $n] 30} 31 32# Return a randomly generated SQL literal. 33# 34proc rvalue {} { 35 switch -- [expr int(rand()*5)] { 36 0 { # SQL NULL value. 37 return NULL 38 } 39 1 { # Integer value. 40 return [expr int(rand()*1024)] 41 } 42 2 { # Real value. 43 return [expr rand()] 44 } 45 3 { # String value. 46 set n [expr int(rand()*2500)] 47 return "'[rstring $n]'" 48 } 49 4 { # Blob value. 50 set n [expr int(rand()*2500)] 51 return "CAST('[rstring $n]' AS BLOB)" 52 } 53 } 54} 55 56proc db_checksum {} { 57 set cksum [execsql { SELECT md5sum(a, b, c) FROM t1 }] 58 append cksum [execsql { SELECT md5sum(d, e, f) FROM t2 }] 59 set cksum 60} 61 62# Modify a single byte in the file 'test.db' using tcl IO commands. The 63# argument value, which must be an integer, determines both the offset of 64# the byte that is modified, and the value that it is set to. The lower 65# 8 bits of iMod determine the new byte value. The offset of the byte 66# modified is the value of ($iMod >> 8). 67# 68# The return value is the iMod value required to restore the file 69# to its original state. The command: 70# 71# modify_database [modify_database $x] 72# 73# leaves the file in the same state as it was in at the start of the 74# command (assuming that the file is at least ($x>>8) bytes in size). 75# 76proc modify_database {iMod} { 77 set blob [binary format c [expr {$iMod&0xFF}]] 78 set offset [expr {$iMod>>8}] 79 80 set fd [open test.db r+] 81 fconfigure $fd -encoding binary -translation binary 82 seek $fd $offset 83 set old_blob [read $fd 1] 84 seek $fd $offset 85 puts -nonewline $fd $blob 86 close $fd 87 88 binary scan $old_blob c iOld 89 return [expr {($offset<<8) + ($iOld&0xFF)}] 90} 91 92proc purge_pcache {} { 93 ifcapable !memorymanage { 94 db close 95 sqlite3 db test.db 96 } else { 97 sqlite3_release_memory 10000000 98 } 99 if {[lindex [pcache_stats] 1] != 0} { 100 error "purge_pcache failed: [pcache_stats]" 101 } 102} 103 104# This block creates a database to work with. 105# 106do_test fuzz3-1 { 107 execsql { 108 BEGIN; 109 CREATE TABLE t1(a, b, c); 110 CREATE TABLE t2(d, e, f); 111 CREATE INDEX i1 ON t1(a, b, c); 112 CREATE INDEX i2 ON t2(d, e, f); 113 } 114 for {set i 0} {$i < 50} {incr i} { 115 execsql "INSERT INTO t1 VALUES([rvalue], [rvalue], [rvalue])" 116 execsql "INSERT INTO t2 VALUES([rvalue], [rvalue], [rvalue])" 117 } 118 execsql COMMIT 119} {} 120 121set ::cksum [db_checksum] 122do_test fuzz3-2 { 123 db_checksum 124} $::cksum 125 126for {set ii 0} {$ii < 5000} {incr ii} { 127 purge_pcache 128 129 # Randomly modify a single byte of the database file somewhere within 130 # the first 100KB of the file. 131 set iNew [expr int(rand()*5*1024*256)] 132 set iOld [modify_database $iNew] 133 134 set iTest 0 135 foreach sql { 136 {SELECT * FROM t2 ORDER BY d} 137 {SELECT * FROM t1} 138 {SELECT * FROM t2} 139 {SELECT * FROM t1 ORDER BY a} 140 {SELECT * FROM t1 WHERE a = (SELECT a FROM t1 WHERE rowid=25)} 141 {SELECT * FROM t2 WHERE d = (SELECT d FROM t2 WHERE rowid=1)} 142 {SELECT * FROM t2 WHERE d = (SELECT d FROM t2 WHERE rowid=50)} 143 {PRAGMA integrity_check} 144 } { 145 do_test fuzz3-$ii.$iNew.[incr iTest] { 146 foreach {rc msg} [catchsql $sql] {} 147 if {$rc == 0 148 || $msg eq "database or disk is full" 149 || $msg eq "database disk image is malformed" 150 || $msg eq "file is encrypted or is not a database" 151 || [string match "malformed database schema*" $msg] 152 } { 153 set msg ok 154 } 155 set msg 156 } {ok} 157 } 158 159 # Restore the original database file content. Test that the correct 160 # checksum is now returned. 161 # 162 purge_pcache 163 modify_database $iOld 164 do_test fuzz3-$ii.$iNew.[incr iTest] { 165 db_checksum 166 } $::cksum 167} 168 169finish_test 170