# 2007 May 10 # # The author disclaims copyright to this source code. In place of # a legal notice, here is a blessing: # # May you do good and not evil. # May you find forgiveness for yourself and forgive others. # May you share freely, never taking more than you give. # #*********************************************************************** # This file implements regression tests for SQLite library. The focus # of this file is checking the libraries response to subtly corrupting # the database file by changing the values of pseudo-randomly selected # bytes. # # $Id: fuzz3.test,v 1.3 2009/01/05 17:19:03 drh Exp $ set testdir [file dirname $argv0] source $testdir/tester.tcl # These tests deal with corrupt database files # database_may_be_corrupt test_set_config_pagecache 0 0 expr srand(123) proc rstring {n} { set str s while {[string length $str] < $n} { append str [expr rand()] } return [string range $str 0 $n] } # Return a randomly generated SQL literal. # proc rvalue {} { switch -- [expr int(rand()*5)] { 0 { # SQL NULL value. return NULL } 1 { # Integer value. return [expr int(rand()*1024)] } 2 { # Real value. return [expr rand()] } 3 { # String value. set n [expr int(rand()*2500)] return "'[rstring $n]'" } 4 { # Blob value. set n [expr int(rand()*2500)] return "CAST('[rstring $n]' AS BLOB)" } } } proc db_checksum {} { set cksum [execsql { SELECT md5sum(a, b, c) FROM t1 }] append cksum [execsql { SELECT md5sum(d, e, f) FROM t2 }] set cksum } # Modify a single byte in the file 'test.db' using tcl IO commands. The # argument value, which must be an integer, determines both the offset of # the byte that is modified, and the value that it is set to. The lower # 8 bits of iMod determine the new byte value. The offset of the byte # modified is the value of ($iMod >> 8). # # The return value is the iMod value required to restore the file # to its original state. The command: # # modify_database [modify_database $x] # # leaves the file in the same state as it was in at the start of the # command (assuming that the file is at least ($x>>8) bytes in size). # proc modify_database {iMod} { set blob [binary format c [expr {$iMod&0xFF}]] set offset [expr {$iMod>>8}] set fd [open test.db r+] fconfigure $fd -encoding binary -translation binary seek $fd $offset set old_blob [read $fd 1] seek $fd $offset puts -nonewline $fd $blob close $fd binary scan $old_blob c iOld return [expr {($offset<<8) + ($iOld&0xFF)}] } proc purge_pcache {} { ifcapable !memorymanage { db close sqlite3 db test.db } else { sqlite3_release_memory 10000000 } if {[lindex [pcache_stats] 1] != 0} { error "purge_pcache failed: [pcache_stats]" } } # This block creates a database to work with. # do_test fuzz3-1 { execsql { BEGIN; CREATE TABLE t1(a, b, c); CREATE TABLE t2(d, e, f); CREATE INDEX i1 ON t1(a, b, c); CREATE INDEX i2 ON t2(d, e, f); } for {set i 0} {$i < 50} {incr i} { execsql "INSERT INTO t1 VALUES([rvalue], [rvalue], [rvalue])" execsql "INSERT INTO t2 VALUES([rvalue], [rvalue], [rvalue])" } execsql COMMIT } {} set ::cksum [db_checksum] do_test fuzz3-2 { db_checksum } $::cksum for {set ii 0} {$ii < 5000} {incr ii} { purge_pcache # Randomly modify a single byte of the database file somewhere within # the first 100KB of the file. set iNew [expr int(rand()*5*1024*256)] set iOld [modify_database $iNew] set iTest 0 foreach sql { {SELECT * FROM t2 ORDER BY d} {SELECT * FROM t1} {SELECT * FROM t2} {SELECT * FROM t1 ORDER BY a} {SELECT * FROM t1 WHERE a = (SELECT a FROM t1 WHERE rowid=25)} {SELECT * FROM t2 WHERE d = (SELECT d FROM t2 WHERE rowid=1)} {SELECT * FROM t2 WHERE d = (SELECT d FROM t2 WHERE rowid=50)} {PRAGMA integrity_check} } { do_test fuzz3-$ii.$iNew.[incr iTest] { foreach {rc msg} [catchsql $sql] {} if {$rc == 0 || $msg eq "database or disk is full" || $msg eq "database disk image is malformed" || $msg eq "file is encrypted or is not a database" || [string match "malformed database schema*" $msg] } { set msg ok } set msg } {ok} } # Restore the original database file content. Test that the correct # checksum is now returned. # purge_pcache modify_database $iOld do_test fuzz3-$ii.$iNew.[incr iTest] { db_checksum } $::cksum } test_restore_config_pagecache finish_test