bsd/hfs/hfscommon/Misc/BTreeWrapper.c

   1 /*
   2  * Copyright (c) 2000, 2002, 2005-2008 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28
  29 #include "../headers/BTreesPrivate.h"
  30
  31
  32 // local routines
  33 static OSErr    CheckBTreeKey(const BTreeKey *key, const BTreeControlBlock *btcb);
  34 static Boolean  ValidHFSRecord(const void *record, const BTreeControlBlock *btcb, u_int16_t recordSize);
  35
  36
  37 OSErr ReplaceBTreeRecord(FileReference refNum, const void* key, u_int32_t hint, void *newData, u_int16_t dataSize, u_int32_t *newHint)
  38 {
  39         FSBufferDescriptor      btRecord;
  40         BTreeIterator           iterator;
  41         FCB                                     *fcb;
  42         BTreeControlBlock       *btcb;
  43         OSStatus                        result;
  44
  45
  46         fcb = GetFileControlBlock(refNum);
  47         btcb = (BTreeControlBlock*) fcb->fcbBTCBPtr;
  48
  49         btRecord.bufferAddress = newData;
  50         btRecord.itemSize = dataSize;
  51         btRecord.itemCount = 1;
  52
  53         iterator.hint.nodeNum = hint;
  54
  55         result = CheckBTreeKey((const BTreeKey *) key, btcb);
  56         ExitOnError(result);
  57
  58         BlockMoveData(key, &iterator.key, CalcKeySize(btcb, (const BTreeKey *) key));           //\80\80 should we range check against maxkeylen?
  59
  60         if ( DEBUG_BUILD && !ValidHFSRecord(newData, btcb, dataSize) )
  61                 DebugStr("ReplaceBTreeRecord: bad record?");
  62
  63         result = BTReplaceRecord( fcb, &iterator, &btRecord, dataSize );
  64
  65         *newHint = iterator.hint.nodeNum;
  66
  67         //\80\80 do we need to invalidate the iterator?
  68
  69 ErrorExit:
  70
  71         return result;
  72 }
  73
  74
  75
  76 static OSErr CheckBTreeKey(const BTreeKey *key, const BTreeControlBlock *btcb)
  77 {
  78         u_int16_t       keyLen;
  79
  80         if ( btcb->attributes & kBTBigKeysMask )
  81                 keyLen = key->length16;
  82         else
  83                 keyLen = key->length8;
  84
  85         if ( (keyLen < 6) || (keyLen > btcb->maxKeyLength) )
  86         {
  87                 if ( DEBUG_BUILD )
  88                         DebugStr("CheckBTreeKey: bad key length!");
  89                 return fsBTInvalidKeyLengthErr;
  90         }
  91
  92         return noErr;
  93 }
  94
  95
  96 static Boolean ValidHFSRecord(const void *record, const BTreeControlBlock *btcb, u_int16_t recordSize)
  97 {
  98         u_int32_t                       cNodeID;
  99
 100         if ( btcb->maxKeyLength == kHFSExtentKeyMaximumLength )
 101         {
 102                 return ( recordSize == sizeof(HFSExtentRecord) );
 103         }
 104         else if (btcb->maxKeyLength == kHFSPlusExtentKeyMaximumLength )
 105         {
 106                 return ( recordSize == sizeof(HFSPlusExtentRecord) );
 107         }
 108         else // Catalog record
 109         {
 110                 const CatalogRecord *catalogRecord = (const CatalogRecord*) record;
 111
 112                 switch(catalogRecord->recordType)
 113                 {
 114                         case kHFSFolderRecord:
 115                         {
 116                                 if ( recordSize != sizeof(HFSCatalogFolder) )
 117                                         return false;
 118                                 if ( catalogRecord->hfsFolder.flags != 0 )
 119                                         return false;
 120                                 if ( catalogRecord->hfsFolder.valence > 0x7FFF )
 121                                         return false;
 122
 123                                 cNodeID = catalogRecord->hfsFolder.folderID;
 124
 125                                 if ( (cNodeID == 0) || (cNodeID < 16 && cNodeID > 2) )
 126                                         return false;
 127                         }
 128                         break;
 129
 130                         case kHFSPlusFolderRecord:
 131                         {
 132                                 if ( recordSize != sizeof(HFSPlusCatalogFolder) )
 133                                         return false;
 134                                 if ( catalogRecord->hfsPlusFolder.flags != 0 )
 135                                         return false;
 136                                 if ( catalogRecord->hfsPlusFolder.valence > 0x7FFF )
 137                                         return false;
 138
 139                                 cNodeID = catalogRecord->hfsPlusFolder.folderID;
 140
 141                                 if ( (cNodeID == 0) || (cNodeID < 16 && cNodeID > 2) )
 142                                         return false;
 143                         }
 144                         break;
 145
 146                         case kHFSFileRecord:
 147                         {
 148 //                              u_int16_t                                       i;
 149                                 HFSExtentDescriptor     *dataExtent;
 150                                 HFSExtentDescriptor     *rsrcExtent;
 151
 152                                 if ( recordSize != sizeof(HFSCatalogFile) )
 153                                         return false;
 154                                 if ( (catalogRecord->hfsFile.flags & ~(0x83)) != 0 )
 155                                         return false;
 156
 157                                 cNodeID = catalogRecord->hfsFile.fileID;
 158
 159                                 if ( cNodeID < 16 )
 160                                         return false;
 161
 162                                 // make sure 0 ¾ LEOF ¾ PEOF for both forks
 163
 164                                 if ( catalogRecord->hfsFile.dataLogicalSize < 0 )
 165                                         return false;
 166                                 if ( catalogRecord->hfsFile.dataPhysicalSize < catalogRecord->hfsFile.dataLogicalSize )
 167                                         return false;
 168                                 if ( catalogRecord->hfsFile.rsrcLogicalSize < 0 )
 169                                         return false;
 170                                 if ( catalogRecord->hfsFile.rsrcPhysicalSize < catalogRecord->hfsFile.rsrcLogicalSize )
 171                                         return false;
 172
 173                                 dataExtent = (HFSExtentDescriptor*) &catalogRecord->hfsFile.dataExtents;
 174                                 rsrcExtent = (HFSExtentDescriptor*) &catalogRecord->hfsFile.rsrcExtents;
 175
 176 #if 0
 177                                 for (i = 0; i < kHFSExtentDensity; ++i)
 178                                 {
 179                                         if ( (dataExtent[i].blockCount > 0) && (dataExtent[i].startBlock == 0) )
 180                                                 return false;
 181                                         if ( (rsrcExtent[i].blockCount > 0) && (rsrcExtent[i].startBlock == 0) )
 182                                                 return false;
 183                                 }
 184 #endif
 185                         }
 186                         break;
 187
 188                         case kHFSPlusFileRecord:
 189                         {
 190 //                              u_int16_t                                       i;
 191                                 HFSPlusExtentDescriptor *dataExtent;
 192                                 HFSPlusExtentDescriptor *rsrcExtent;
 193
 194                                 if ( recordSize != sizeof(HFSPlusCatalogFile) )
 195                                         return false;
 196                                 if ( (catalogRecord->hfsPlusFile.flags & ~(0x83)) != 0 )
 197                                         return false;
 198
 199                                 cNodeID = catalogRecord->hfsPlusFile.fileID;
 200
 201                                 if ( cNodeID < 16 )
 202                                         return false;
 203
 204                                 // make sure 0 ¾ LEOF ¾ PEOF for both forks
 205
 206                                 dataExtent = (HFSPlusExtentDescriptor*) &catalogRecord->hfsPlusFile.dataFork.extents;
 207                                 rsrcExtent = (HFSPlusExtentDescriptor*) &catalogRecord->hfsPlusFile.resourceFork.extents;
 208
 209 #if 0
 210                                 for (i = 0; i < kHFSPlusExtentDensity; ++i)
 211                                 {
 212                                         if ( (dataExtent[i].blockCount > 0) && (dataExtent[i].startBlock == 0) )
 213                                                 return false;
 214                                         if ( (rsrcExtent[i].blockCount > 0) && (rsrcExtent[i].startBlock == 0) )
 215                                                 return false;
 216                                 }
 217 #endif
 218                         }
 219                         break;
 220
 221                         case kHFSFolderThreadRecord:
 222                         case kHFSFileThreadRecord:
 223                         {
 224                                 if ( recordSize != sizeof(HFSCatalogThread) )
 225                                         return false;
 226
 227                                 cNodeID = catalogRecord->hfsThread.parentID;
 228                                 if ( (cNodeID == 0) || (cNodeID < 16 && cNodeID > 2) )
 229                                         return false;
 230
 231                                 if ( (catalogRecord->hfsThread.nodeName[0] == 0) ||
 232                                          (catalogRecord->hfsThread.nodeName[0] > 31) )
 233                                         return false;
 234                         }
 235                         break;
 236
 237                         case kHFSPlusFolderThreadRecord:
 238                         case kHFSPlusFileThreadRecord:
 239                         {
 240                                 if ( recordSize > sizeof(HFSPlusCatalogThread) || recordSize < (sizeof(HFSPlusCatalogThread) - sizeof(HFSUniStr255)))
 241                                         return false;
 242
 243                                 cNodeID = catalogRecord->hfsPlusThread.parentID;
 244                                 if ( (cNodeID == 0) || (cNodeID < 16 && cNodeID > 2) )
 245                                         return false;
 246
 247                                 if ( (catalogRecord->hfsPlusThread.nodeName.length == 0) ||
 248                                          (catalogRecord->hfsPlusThread.nodeName.length > 255) )
 249                                         return false;
 250                         }
 251                         break;
 252
 253                         default:
 254                                 return false;
 255                 }
 256         }
 257
 258         return true;    // record appears to be OK
 259 }