# 2004 August 30
#
# 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.
#
# This file implements tests to make sure SQLite does not crash or
# segfault if it sees a corrupt database file.
#
# $Id: corrupt2.test,v 1.20 2009/04/06 17:50:03 danielk1977 Exp $

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix corrupt2

# Do not use a codec for tests in this file, as the database file is
# manipulated directly using tcl scripts (using the [hexio_write] command).
#
do_not_use_codec

# These tests deal with corrupt database files
#
database_may_be_corrupt

set presql ""
catch { set presql "$::G(perm:presql);" }
unset -nocomplain ::G(perm:presql)

# The following tests - corrupt2-1.* - create some databases corrupted in
# specific ways and ensure that SQLite detects them as corrupt.
#
do_test corrupt2-1.1 {
  execsql {
    PRAGMA auto_vacuum=0;
    PRAGMA page_size=1024;
    CREATE TABLE abc(a, b, c);
  }
} {}

do_test corrupt2-1.2 {

  # Corrupt the 16 byte magic string at the start of the file
  forcedelete corrupt.db
  forcedelete corrupt.db-journal
  forcecopy test.db corrupt.db
  set f [open corrupt.db RDWR]
  seek $f 8 start
  puts $f blah
  close $f

  sqlite3 db2 corrupt.db
  catchsql "
    $::presql
    SELECT * FROM sqlite_master;
  " db2
} {1 {file is not a database}}

do_test corrupt2-1.3 {
  db2 close

  # Corrupt the page-size (bytes 16 and 17 of page 1).
  forcedelete corrupt.db
  forcedelete corrupt.db-journal
  forcecopy test.db corrupt.db
  set f [open corrupt.db RDWR]
  fconfigure $f -encoding binary
  seek $f 16 start
  puts -nonewline $f "\x00\xFF"
  close $f

  sqlite3 db2 corrupt.db
  catchsql "
    $::presql
    SELECT * FROM sqlite_master;
  " db2
} {1 {file is not a database}}

do_test corrupt2-1.4 {
  db2 close

  # Corrupt the free-block list on page 1.
  forcedelete corrupt.db
  forcedelete corrupt.db-journal
  forcecopy test.db corrupt.db
  set f [open corrupt.db RDWR]
  fconfigure $f -encoding binary
  seek $f 101 start
  puts -nonewline $f "\xFF\xFF"
  close $f

  sqlite3 db2 corrupt.db
  # Note: This test is no longer meaningful due to the deferred computation
  # of MemPage.nFree 
  catchsql {PRAGMA quick_check} db2
} {0 {{*** in database main ***
Tree 1 page 1: free space corruption}}}

do_test corrupt2-1.5 {
  db2 close

  # Corrupt the free-block list on page 1.
  forcedelete corrupt.db
  forcedelete corrupt.db-journal
  forcecopy test.db corrupt.db
  set f [open corrupt.db RDWR]
  fconfigure $f -encoding binary
  seek $f 101 start
  puts -nonewline $f "\x00\xC8"
  seek $f 200 start
  puts -nonewline $f "\x00\x00"
  puts -nonewline $f "\x10\x00"
  close $f

  sqlite3 db2 corrupt.db
  catchsql {PRAGMA quick_check} db2
} {0 {{*** in database main ***
Tree 1 page 1: free space corruption}}}
db2 close

# Corrupt a database by having 2 indices of the same name:
do_test corrupt2-2.1 {

  forcedelete corrupt.db
  forcedelete corrupt.db-journal
  forcecopy test.db corrupt.db

  sqlite3 db2 corrupt.db 
  sqlite3_db_config db2 DEFENSIVE 0
  execsql "
    $::presql
    CREATE INDEX a1 ON abc(a);
    CREATE INDEX a2 ON abc(b);
    PRAGMA writable_schema = 1;
    UPDATE sqlite_master 
      SET name = 'a3', sql = 'CREATE INDEX a3' || substr(sql, 16, 10000)
      WHERE type = 'index';
    PRAGMA writable_schema = 0;
  " db2

  db2 close
  sqlite3 db2 corrupt.db 
  catchsql "
    $::presql
    SELECT * FROM sqlite_master;
  " db2
} {1 {malformed database schema (a3) - index a3 already exists}}

db2 close

do_test corrupt2-3.1 {
  forcedelete corrupt.db
  forcedelete corrupt.db-journal
  sqlite3 db2 corrupt.db 

  execsql "
    $::presql
    PRAGMA auto_vacuum = 1;
    PRAGMA page_size = 1024;
    CREATE TABLE t1(a, b, c);
    CREATE TABLE t2(a, b, c);
    INSERT INTO t2 VALUES(randomblob(100), randomblob(100), randomblob(100));
    INSERT INTO t2 SELECT * FROM t2;
    INSERT INTO t2 SELECT * FROM t2;
    INSERT INTO t2 SELECT * FROM t2;
    INSERT INTO t2 SELECT * FROM t2;
  " db2

  db2 close

  # On the root page of table t2 (page 4), set one of the child page-numbers
  # to 0. This corruption will be detected when SQLite attempts to update
  # the pointer-map after moving the content of page 4 to page 3 as part
  # of the DROP TABLE operation below.
  #
  set fd [open corrupt.db r+]
  fconfigure $fd -encoding binary -translation binary
  seek $fd [expr 1024*3 + 12]
  set zCelloffset [read $fd 2]
  binary scan $zCelloffset S iCelloffset
  seek $fd [expr 1024*3 + $iCelloffset]
  puts -nonewline $fd "\00\00\00\00" 
  close $fd

  sqlite3 db2 corrupt.db 
  catchsql "
    $::presql
    DROP TABLE t1;
  " db2
} {1 {database disk image is malformed}}

do_test corrupt2-4.1 {
  catchsql {
    SELECT * FROM t2;
  } db2
} {1 {database disk image is malformed}}

db2 close

unset -nocomplain result
do_test corrupt2-5.1 {
  forcedelete corrupt.db
  forcedelete corrupt.db-journal
  sqlite3 db2 corrupt.db 

  execsql "
    $::presql
    PRAGMA auto_vacuum = 0;
    PRAGMA page_size = 1024;
    CREATE TABLE t1(a, b, c);
    CREATE TABLE t2(a, b, c);
    INSERT INTO t2 VALUES(randomblob(100), randomblob(100), randomblob(100));
    INSERT INTO t2 SELECT * FROM t2;
    INSERT INTO t2 SELECT * FROM t2;
    INSERT INTO t2 SELECT * FROM t2;
    INSERT INTO t2 SELECT * FROM t2;
    INSERT INTO t1 SELECT * FROM t2;
  " db2

  db2 close

  # This block links a page from table t2 into the t1 table structure.
  #
  set fd [open corrupt.db r+]
  fconfigure $fd -encoding binary -translation binary
  seek $fd [expr 1024 + 12]
  set zCelloffset [read $fd 2]
  binary scan $zCelloffset S iCelloffset
  seek $fd [expr 1024 + $iCelloffset]
  set zChildPage [read $fd 4]
  seek $fd [expr 2*1024 + 12]
  set zCelloffset [read $fd 2]
  binary scan $zCelloffset S iCelloffset
  seek $fd [expr 2*1024 + $iCelloffset]
  puts -nonewline $fd $zChildPage
  close $fd

  sqlite3 db2 corrupt.db 
  db2 eval $::presql
  db2 eval {SELECT rowid FROM t1} {
    set result [db2 eval {pragma integrity_check}]
    break
  }
  set result
} {{*** in database main ***
Tree 2 page 2 cell 0: 2nd reference to page 10
Page 4: never used}}

db2 close

proc corruption_test {args} {
  set A(-corrupt) {}
  set A(-sqlprep) {}
  set A(-tclprep) {}
  array set A $args

  catch {db close}
  forcedelete corrupt.db
  forcedelete corrupt.db-journal

  sqlite3 db corrupt.db 
  sqlite3_db_config db DEFENSIVE 0
  db eval $::presql
  eval $A(-tclprep)
  db eval $A(-sqlprep)
  db close

  eval $A(-corrupt)

  sqlite3 db corrupt.db
  eval $A(-test)
}

ifcapable autovacuum {
  # The tests within this block - corrupt2-6.* - aim to test corruption
  # detection within an incremental-vacuum. When an incremental-vacuum
  # step is executed, the last non-free page of the database file is 
  # moved into a free space in the body of the file. After doing so,
  # the page reference in the parent page must be updated to refer
  # to the new location. These tests test the outcome of corrupting
  # that page reference before performing the incremental vacuum.
  #

  # The last page in the database page is the second page 
  # in an overflow chain.
  #
  corruption_test -sqlprep {
    PRAGMA auto_vacuum = incremental;
    PRAGMA page_size = 1024;
    CREATE TABLE t1(a, b);
    INSERT INTO t1 VALUES(1, randomblob(2500));
    INSERT INTO t1 VALUES(2, randomblob(2500));
    DELETE FROM t1 WHERE a = 1;
  } -corrupt {
    hexio_write corrupt.db [expr 1024*5] 00000008
  } -test {
    do_test corrupt2-6.1 {
      catchsql " $::presql pragma incremental_vacuum = 1 "
    } {1 {database disk image is malformed}}
  }

  # The last page in the database page is a non-root b-tree page.
  #
  corruption_test -sqlprep {
    PRAGMA auto_vacuum = incremental;
    PRAGMA page_size = 1024;
    CREATE TABLE t1(a INTEGER PRIMARY KEY, b);
    INSERT INTO t1 VALUES(1, randomblob(2500));
    INSERT INTO t1 VALUES(2, randomblob(50));
    INSERT INTO t1 SELECT NULL, randomblob(50) FROM t1;
    INSERT INTO t1 SELECT NULL, randomblob(50) FROM t1;
    INSERT INTO t1 SELECT NULL, randomblob(50) FROM t1;
    INSERT INTO t1 SELECT NULL, randomblob(50) FROM t1;
    DELETE FROM t1 WHERE a = 1;
  } -corrupt {
    hexio_write corrupt.db [expr 1024*2 + 8] 00000009
  } -test {
    do_test corrupt2-6.2 {
      catchsql " $::presql pragma incremental_vacuum = 1 "
    } {1 {database disk image is malformed}}
  }

  # Set up a pointer-map entry so that the last page of the database
  # file appears to be a b-tree root page. This should be detected
  # as corruption.
  #
  corruption_test -sqlprep {
    PRAGMA auto_vacuum = incremental;
    PRAGMA page_size = 1024;
    CREATE TABLE t1(a INTEGER PRIMARY KEY, b);
    INSERT INTO t1 VALUES(1, randomblob(2500));
    INSERT INTO t1 VALUES(2, randomblob(2500));
    INSERT INTO t1 VALUES(3, randomblob(2500));
    DELETE FROM t1 WHERE a = 1;
  } -corrupt {
    set nPage [expr [file size corrupt.db] / 1024]
    hexio_write corrupt.db [expr 1024 + ($nPage-3)*5] 010000000
  } -test {
    do_test corrupt2-6.3 {
      catchsql " $::presql pragma incremental_vacuum = 1 "
    } {1 {database disk image is malformed}}
  }

  if {![nonzero_reserved_bytes]} {
    corruption_test -sqlprep {
      PRAGMA auto_vacuum = 1;
      PRAGMA page_size = 1024;
      CREATE TABLE t1(a INTEGER PRIMARY KEY, b);
      INSERT INTO t1 VALUES(1, randomblob(2500));
      DELETE FROM t1 WHERE a = 1;
    } -corrupt {
      set nAppend [expr 1024*207 - [file size corrupt.db]]
      set fd [open corrupt.db r+]
      seek $fd 0 end
      puts -nonewline $fd [string repeat x $nAppend]
      close $fd
      hexio_write corrupt.db 28 00000000
    } -test {
      do_test corrupt2-6.4 {
        catchsql " 
          $::presql 
          BEGIN EXCLUSIVE;
          COMMIT;
        "
      } {1 {database disk image is malformed}}
    }
  }
}


set sqlprep {
  PRAGMA auto_vacuum = 0;
  PRAGMA page_size = 1024;
  CREATE TABLE t1(a INTEGER PRIMARY KEY, b);
  CREATE INDEX i1 ON t1(b);
  INSERT INTO t1 VALUES(1, randomblob(50));
  INSERT INTO t1 SELECT NULL, randomblob(50) FROM t1;
  INSERT INTO t1 SELECT NULL, randomblob(50) FROM t1;
  INSERT INTO t1 SELECT NULL, randomblob(50) FROM t1;
  INSERT INTO t1 SELECT NULL, randomblob(50) FROM t1;
  INSERT INTO t1 SELECT NULL, randomblob(50) FROM t1;
  INSERT INTO t1 SELECT NULL, randomblob(50) FROM t1;
}

corruption_test -sqlprep $sqlprep -corrupt {
  # Set the page-flags of one of the leaf pages of the index B-Tree to
  # 0x0D (interpreted by SQLite as "leaf page of a table B-Tree").
  #
  set fd [open corrupt.db r+]
  fconfigure $fd -translation binary -encoding binary
  seek $fd [expr 1024*2 + 8] 
  set zRightChild [read $fd 4]
  binary scan $zRightChild I iRightChild
  seek $fd [expr 1024*($iRightChild-1)]
  puts -nonewline $fd "\x0D"
  close $fd
} -test {
  do_test corrupt2-7.1 {
    catchsql " $::presql SELECT b FROM t1 ORDER BY b ASC "
  } {1 {database disk image is malformed}}
}

corruption_test -sqlprep $sqlprep -corrupt {
  # Mess up the page-header of one of the leaf pages of the index B-Tree.
  # The corruption is detected as part of an OP_Prev opcode.
  #
  set fd [open corrupt.db r+]
  fconfigure $fd -translation binary -encoding binary
  seek $fd [expr 1024*2 + 12] 
  set zCellOffset [read $fd 2]
  binary scan $zCellOffset S iCellOffset
  seek $fd [expr 1024*2 + $iCellOffset]
  set zChild [read $fd 4]
  binary scan $zChild I iChild
  seek $fd [expr 1024*($iChild-1)+3]
  puts -nonewline $fd "\xFFFF"
  close $fd
} -test {
  do_test corrupt2-7.1 {
    catchsql " $::presql SELECT b FROM t1 ORDER BY b DESC "
  } {1 {database disk image is malformed}}
}

corruption_test -sqlprep $sqlprep -corrupt {
  # Set the page-flags of one of the leaf pages of the table B-Tree to
  # 0x0A (interpreted by SQLite as "leaf page of an index B-Tree").
  #
  set fd [open corrupt.db r+]
  fconfigure $fd -translation binary -encoding binary
  seek $fd [expr 1024*1 + 8] 
  set zRightChild [read $fd 4]
  binary scan $zRightChild I iRightChild
  seek $fd [expr 1024*($iRightChild-1)]
  puts -nonewline $fd "\x0A"
  close $fd
} -test {
  do_test corrupt2-8.1 {
    catchsql " $::presql SELECT * FROM t1 WHERE rowid=1000 "
  } {1 {database disk image is malformed}}
}

corruption_test -sqlprep {
  CREATE TABLE t1(a, b, c); CREATE TABLE t8(a, b, c); CREATE TABLE tE(a, b, c);
  CREATE TABLE t2(a, b, c); CREATE TABLE t9(a, b, c); CREATE TABLE tF(a, b, c);
  CREATE TABLE t3(a, b, c); CREATE TABLE tA(a, b, c); CREATE TABLE tG(a, b, c);
  CREATE TABLE t4(a, b, c); CREATE TABLE tB(a, b, c); CREATE TABLE tH(a, b, c);
  CREATE TABLE t5(a, b, c); CREATE TABLE tC(a, b, c); CREATE TABLE tI(a, b, c);
  CREATE TABLE t6(a, b, c); CREATE TABLE tD(a, b, c); CREATE TABLE tJ(a, b, c);
  CREATE TABLE x1(a, b, c); CREATE TABLE x8(a, b, c); CREATE TABLE xE(a, b, c);
  CREATE TABLE x2(a, b, c); CREATE TABLE x9(a, b, c); CREATE TABLE xF(a, b, c);
  CREATE TABLE x3(a, b, c); CREATE TABLE xA(a, b, c); CREATE TABLE xG(a, b, c);
  CREATE TABLE x4(a, b, c); CREATE TABLE xB(a, b, c); CREATE TABLE xH(a, b, c);
  CREATE TABLE x5(a, b, c); CREATE TABLE xC(a, b, c); CREATE TABLE xI(a, b, c);
  CREATE TABLE x6(a, b, c); CREATE TABLE xD(a, b, c); CREATE TABLE xJ(a, b, c);
} -corrupt {
  set fd [open corrupt.db r+]
  fconfigure $fd -translation binary -encoding binary
  seek $fd 108
  set zRightChild [read $fd 4]
  binary scan $zRightChild I iRightChild
  seek $fd [expr 1024*($iRightChild-1)+3]
  puts -nonewline $fd "\x00\x00"
  close $fd
} -test {
  do_test corrupt2-9.1 {
    catchsql " $::presql SELECT sql FROM sqlite_master "
  } {1 {database disk image is malformed}}
}

corruption_test -sqlprep {
  CREATE TABLE t1(a, b, c);
  CREATE TABLE t2(a, b, c);
  PRAGMA writable_schema = 1;
  UPDATE sqlite_master SET rootpage = NULL WHERE name = 't2';
} -test {
  do_test corrupt2-10.1 {
    catchsql " $::presql SELECT * FROM t2 "
  } {1 {malformed database schema (t2)}}
  do_test corrupt2-10.2 {
    sqlite3_errcode db
  } {SQLITE_CORRUPT}
}

corruption_test -sqlprep {
  PRAGMA auto_vacuum = incremental;
  CREATE TABLE t1(a INTEGER PRIMARY KEY, b);
  CREATE TABLE t2(a INTEGER PRIMARY KEY, b);
  INSERT INTO t1 VALUES(1, randstr(100,100));
  INSERT INTO t1 SELECT NULL, randstr(100,100) FROM t1;
  INSERT INTO t1 SELECT NULL, randstr(100,100) FROM t1;
  INSERT INTO t1 SELECT NULL, randstr(100,100) FROM t1;
  INSERT INTO t1 SELECT NULL, randstr(100,100) FROM t1;
  INSERT INTO t1 SELECT NULL, randstr(100,100) FROM t1;
  INSERT INTO t2 SELECT * FROM t1;
  DELETE FROM t1;
} -corrupt {
  set offset [expr [file size corrupt.db] - 1024]
  hexio_write corrupt.db $offset FF 
  hexio_write corrupt.db 24   12345678
} -test {
  do_test corrupt2-11.1 {
    catchsql " $::presql PRAGMA incremental_vacuum "
  } {1 {database disk image is malformed}}
}
corruption_test -sqlprep {
  PRAGMA auto_vacuum = incremental;
  CREATE TABLE t1(a INTEGER PRIMARY KEY, b);
  CREATE TABLE t2(a INTEGER PRIMARY KEY, b);
  INSERT INTO t1 VALUES(1, randstr(100,100));
  INSERT INTO t1 SELECT NULL, randstr(100,100) FROM t1;
  INSERT INTO t1 SELECT NULL, randstr(100,100) FROM t1;
  INSERT INTO t1 SELECT NULL, randstr(100,100) FROM t1;
  INSERT INTO t1 SELECT NULL, randstr(100,100) FROM t1;
  INSERT INTO t1 SELECT NULL, randstr(100,100) FROM t1;
  INSERT INTO t2 SELECT * FROM t1;
  DELETE FROM t1;
} -corrupt {
  set pgno [expr [file size corrupt.db] / 1024]
  hexio_write corrupt.db [expr 1024+5*($pgno-3)] 03 
  hexio_write corrupt.db 24   12345678
} -test {
  do_test corrupt2-12.1 {
    catchsql " $::presql PRAGMA incremental_vacuum "
  } {1 {database disk image is malformed}}
}

ifcapable autovacuum {
  # It is not possible for the last page in a database file to be the
  # pending-byte page (AKA the locking page). This test verifies that if
  # an attempt is made to commit a transaction to such an auto-vacuum 
  # database SQLITE_CORRUPT is returned.
  #
  corruption_test -tclprep {
    db eval { 
      PRAGMA auto_vacuum = full;
      PRAGMA page_size = 1024;
      CREATE TABLE t1(a INTEGER PRIMARY KEY, b);
      INSERT INTO t1 VALUES(NULL, randstr(50,50));
    }
    for {set ii 0} {$ii < 10} {incr ii} {
      db eval " $::presql INSERT INTO t1 SELECT NULL, randstr(50,50) FROM t1 "
    }
  } -corrupt {
    do_test corrupt2-13.1 {
      file size corrupt.db
    } $::sqlite_pending_byte
    hexio_write corrupt.db [expr $::sqlite_pending_byte+1023] 00
    hexio_write corrupt.db 28 00000000
  } -test {
    do_test corrupt2-13.2 {
      file size corrupt.db
    } [expr $::sqlite_pending_byte + 1024]
    do_test corrupt2-13.3 {
      catchsql { DELETE FROM t1 WHERE rowid < 30; }
    } {1 {database disk image is malformed}}
  }
}

#-------------------------------------------------------------------------
# Test that PRAGMA integrity_check detects cases where the freelist-count
# header field is smaller than the actual number of pages on the freelist.
#

reset_db
do_execsql_test 14.0 {
  PRAGMA auto_vacuum = 0;
  CREATE TABLE t1(x);
  INSERT INTO t1 VALUES(randomblob(3500));
  DELETE FROM t1;
}

do_execsql_test 14.1 {
  PRAGMA integrity_check;
  PRAGMA freelist_count;
} {ok 3}

# There are now 3 free pages. Modify the header-field so that it 
# (incorrectly) says that just 2 are free.
do_test 14.2 {
  db close
  hexio_write test.db 36 [hexio_render_int32 2]
  sqlite3 db test.db
  execsql { PRAGMA freelist_count }
} {2}

do_execsql_test 14.3 {
  PRAGMA integrity_check;
} {{*** in database main ***
Freelist: size is 3 but should be 2}}

# Use 2 of the free pages on the free-list.
#
do_execsql_test 14.4 {
  INSERT INTO t1 VALUES(randomblob(2500));
  PRAGMA freelist_count;
} {0}

do_execsql_test 14.5 {
  PRAGMA integrity_check;
} {{*** in database main ***
Freelist: size is 1 but should be 0}}


finish_test

finish_test
