OSSet * IOGUIDPartitionScheme::scan(SInt32 * score)
{
    //
    // Scan the provider media for a GUID partition map.    Returns the set
    // of media objects representing each of the partitions (the retain for
    // the set is passed to the caller), or null should no partition map be
    // found.  The default probe score can be adjusted up or down, based on
    // the confidence of the scan.
    //

    IOBufferMemoryDescriptor * buffer         = 0;
    IOByteCount                bufferSize     = 0;
    UInt32                     fdiskID        = 0;
    disk_blk0 *                fdiskMap       = 0;
    UInt64                     gptBlock       = 0;
    UInt32                     gptCheck       = 0;
    UInt32                     gptCount       = 0;
    UInt32                     gptID          = 0;
    gpt_ent *                  gptMap         = 0;
    UInt32                     gptSize        = 0;
    UInt32                     headerCheck    = 0;
    gpt_hdr *                  headerMap      = 0;
    UInt32                     headerSize     = 0;
    IOMedia *                  media          = getProvider();
    UInt64                     mediaBlockSize = media->getPreferredBlockSize();
    bool                       mediaIsOpen    = false;
    OSSet *                    partitions     = 0;
    IOReturn                   status         = kIOReturnError;

    // Determine whether this media is formatted.

    if ( media->isFormatted() == false )  goto scanErr;

    // Determine whether this media has an appropriate block size.

    if ( (mediaBlockSize % sizeof(disk_blk0)) )  goto scanErr;

    // Allocate a buffer large enough to hold one map, rounded to a media block.

    bufferSize = IORound(sizeof(disk_blk0), mediaBlockSize);
    buffer     = IOBufferMemoryDescriptor::withCapacity(
                                           /* capacity      */ bufferSize,
                                           /* withDirection */ kIODirectionIn );
    if ( buffer == 0 )  goto scanErr;

    // Allocate a set to hold the set of media objects representing partitions.

    partitions = OSSet::withCapacity(8);
    if ( partitions == 0 )  goto scanErr;

    // Open the media with read access.

    mediaIsOpen = open(this, 0, kIOStorageAccessReader);
    if ( mediaIsOpen == false )  goto scanErr;

    // Read the protective map into our buffer.

    status = media->read(this, 0, buffer);
    if ( status != kIOReturnSuccess )  goto scanErr;

    fdiskMap = (disk_blk0 *) buffer->getBytesNoCopy();

    // Determine whether the protective map signature is present.

    if ( OSSwapLittleToHostInt16(fdiskMap->signature) != DISK_SIGNATURE )
    {
         goto scanErr;
    }

    // Scan for valid partition entries in the protective map.

    for ( unsigned index = 0; index < DISK_NPART; index++ )
    {
        if ( fdiskMap->parts[index].systid )
        {
            if ( fdiskMap->parts[index].systid == 0xEE )
            {
                if ( fdiskID )  goto scanErr;

                fdiskID = index + 1;
            }
        }
    }

    if ( fdiskID == 0 )  goto scanErr;

    // Read the partition header into our buffer.

    status = media->read(this, mediaBlockSize, buffer);
    if ( status != kIOReturnSuccess )  goto scanErr;

    headerMap = (gpt_hdr *) buffer->getBytesNoCopy();

    // Determine whether the partition header signature is present.

    if ( memcmp(headerMap->hdr_sig, GPT_HDR_SIG, strlen(GPT_HDR_SIG)) )
    {
        goto scanErr;
    }

    // Determine whether the partition header size is valid.

    headerCheck = OSSwapLittleToHostInt32(headerMap->hdr_crc_self);
    headerSize  = OSSwapLittleToHostInt32(headerMap->hdr_size);

    if ( headerSize < offsetof(gpt_hdr, padding) )
    {
        goto scanErr;
    }

    if ( headerSize > mediaBlockSize )
    {
        goto scanErr;
    }

    // Determine whether the partition header checksum is valid.

    headerMap->hdr_crc_self = 0;

    if ( crc32(0, headerMap, headerSize) != headerCheck )
    {
        goto scanErr;
    }

    // Determine whether the partition entry size is valid.

    gptCheck = OSSwapLittleToHostInt32(headerMap->hdr_crc_table);
    gptSize  = OSSwapLittleToHostInt32(headerMap->hdr_entsz);

    if ( gptSize < sizeof(gpt_ent) )
    {
        goto scanErr;
    }

    if ( gptSize > UINT16_MAX )
    {
        goto scanErr;
    }

    // Determine whether the partition entry count is valid.

    gptBlock = OSSwapLittleToHostInt64(headerMap->hdr_lba_table);
    gptCount = OSSwapLittleToHostInt32(headerMap->hdr_entries);

    if ( gptCount > UINT16_MAX )
    {
        goto scanErr;
    }

    // Allocate a buffer large enough to hold one map, rounded to a media block.

    buffer->release();

    bufferSize = IORound(gptCount * gptSize, mediaBlockSize);
    buffer     = IOBufferMemoryDescriptor::withCapacity(
                                           /* capacity      */ bufferSize,
                                           /* withDirection */ kIODirectionIn );
    if ( buffer == 0 )  goto scanErr;

    // Read the partition header into our buffer.

    status = media->read(this, gptBlock * mediaBlockSize, buffer);
    if ( status != kIOReturnSuccess )  goto scanErr;

    gptMap = (gpt_ent *) buffer->getBytesNoCopy();

    // Determine whether the partition entry checksum is valid.

    if ( crc32(0, gptMap, gptCount * gptSize) != gptCheck )
    {
        goto scanErr;
    }

    // Scan for valid partition entries in the partition map.

    for ( gptID = 1; gptID <= gptCount; gptID++ )
    {
        gptMap = (gpt_ent *) ( ((UInt8 *) buffer->getBytesNoCopy()) +
                               (gptID * gptSize) - gptSize );

        uuid_unswap( gptMap->ent_type );
        uuid_unswap( gptMap->ent_uuid );
 
        if ( isPartitionUsed( gptMap ) )
        {
            // Determine whether the partition is corrupt (fatal).

            if ( isPartitionCorrupt( gptMap, gptID ) )
            {
                goto scanErr;
            }

            // Determine whether the partition is invalid (skipped).

            if ( isPartitionInvalid( gptMap, gptID ) )
            {
                continue;
            }

            // Create a media object to represent this partition.

            IOMedia * newMedia = instantiateMediaObject( gptMap, gptID );

            if ( newMedia )
            {
                partitions->setObject(newMedia);
                newMedia->release();
            }
        }
    }

    // Release our resources.

    close(this);
    buffer->release();

    return partitions;

scanErr:

    // Release our resources.

    if ( mediaIsOpen )  close(this);
    if ( partitions )  partitions->release();
    if ( buffer )  buffer->release();

    return 0;
}
Пример #2
0
bool
AppleFileSystemDriver::mediaNotificationHandler(
												void * target, void * ref,
												IOService * service,
												IONotifier * notifier)
{
    AppleFileSystemDriver *    fs;
    IOMedia *                  media;
    IOReturn                   status         = kIOReturnError;
    OSString *                 contentHint;
    const char *               contentStr;
    VolumeUUID	               volumeUUID;
    OSString *                 uuidProperty;
    uuid_t                     uuid;
    bool                       matched        = false;

    DEBUG_LOG("%s[%p]::%s -> '%s'\n", kClassName, target, __func__, service->getName());

    do {
        fs = OSDynamicCast( AppleFileSystemDriver, (IOService *)target );
        if (fs == 0) break;
		
        media = OSDynamicCast( IOMedia, service );
        if (media == 0) break;
		
        // i.e. does it know how big it is / have a block size
        if ( media->isFormatted() == false )  break;

        // If the media already has a UUID property, try that first.
        uuidProperty = OSDynamicCast( OSString, media->getProperty("UUID") );
        if (uuidProperty != NULL) {
            if (fs->_uuidString && uuidProperty->isEqualTo(fs->_uuidString)) {
		VERBOSE_LOG("existing UUID property matched\n");
                matched = true;
                break;
            }
        }
        
        // only IOMedia's with content hints are interesting
        contentHint = OSDynamicCast( OSString, media->getProperty(kIOMediaContentHintKey) );
        if (contentHint == NULL)  break;
        contentStr = contentHint->getCStringNoCopy();
        if (contentStr == NULL)  break;
        
        // probe based on content hint
        if ( strcmp(contentStr, "Apple_HFS" ) == 0 ||
             strcmp(contentStr, "Apple_HFSX" ) == 0 ||
             strcmp(contentStr, "Apple_Boot" ) == 0 ||
             strcmp(contentStr, "Apple_Recovery" ) == 0 ||
             strcmp(contentStr, "48465300-0000-11AA-AA11-00306543ECAC" ) == 0 ||  /* APPLE_HFS_UUID */
             strcmp(contentStr, "426F6F74-0000-11AA-AA11-00306543ECAC" ) == 0 ||  /* APPLE_BOOT_UUID */
             strcmp(contentStr, "5265636F-7665-11AA-AA11-00306543ECAC" ) == 0 ) { /* APPLE_RECOVERY_UUID */
            status = readHFSUUID( media, (void **)&volumeUUID );
        } else {
            DEBUG_LOG("contentStr %s\n", contentStr);
            break;
        }
        
        if (status != kIOReturnSuccess) {
            break;
        }
		
        if (createUUIDFromName( kFSUUIDNamespaceSHA1,
                                volumeUUID.bytes, kVolumeUUIDValueLength,
                                uuid ) != kIOReturnSuccess) {
            break;
        }
        
#if VERBOSE
        OSString *str = createStringFromUUID(uuid);
	OSString *bsdn = OSDynamicCast(OSString,media->getProperty("BSD Name"));
        if (str) {
            IOLog("  UUID %s found on volume '%s' (%s)\n", str->getCStringNoCopy(),
		    media->getName(), bsdn ? bsdn->getCStringNoCopy():"");
            str->release();
        }
#endif
        
        if (fs->_uuid) {
            if ( uuid_compare(uuid, fs->_uuid) == 0 ) {
                VERBOSE_LOG("  UUID matched on volume %s\n", media->getName());
                matched = true;
            }
        }
		
    } while (false);

    if (matched) {
			
        // prevent more notifications, if notifier is available
        if (fs->_notifier != NULL) {
            fs->_notifier->remove();
            fs->_notifier = NULL;
        }
			
        DEBUG_LOG("%s::%s publishing boot-uuid-media '%s'\n", kClassName, __func__, media->getName());
        IOService::publishResource( kBootUUIDMediaKey, media );

        // Now that our job is done, get rid of the matching property
        // and kill the driver.
        fs->getResourceService()->removeProperty( kBootUUIDKey );
        fs->terminate( kIOServiceRequired );

        // Drop the retain for asynchronous notification
        fs->release( );

        VERBOSE_LOG("%s[%p]::%s returning TRUE\n", kClassName, target, __func__);
            
        return true;
    }
    
    DEBUG_LOG("%s[%p]::%s returning false\n", kClassName, target, __func__);
#if DEBUG
//IOSleep(5000);
#endif
    return false;
}
OSSet * IOFDiskPartitionScheme::scan(SInt32 * score)
{
    //
    // Scan the provider media for an FDisk partition map.  Returns the set
    // of media objects representing each of the partitions (the retain for
    // the set is passed to the caller), or null should no partition map be
    // found.  The default probe score can be adjusted up or down, based on
    // the confidence of the scan.
    //

    IOBufferMemoryDescriptor * buffer         = 0;
    UInt32                     bufferSize     = 0;
    UInt32                     fdiskBlock     = 0;
    UInt32                     fdiskBlockExtn = 0;
    UInt32                     fdiskBlockNext = 0;
    UInt32                     fdiskID        = 0;
    disk_blk0 *                fdiskMap       = 0;
    IOMedia *                  media          = getProvider();
    UInt64                     mediaBlockSize = media->getPreferredBlockSize();
    bool                       mediaIsOpen    = false;
    OSSet *                    partitions     = 0;
    IOReturn                   status         = kIOReturnError;

    // Determine whether this media is formatted.

    if ( media->isFormatted() == false )  goto scanErr;

    // Determine whether this media has an appropriate block size.

    if ( (mediaBlockSize % sizeof(disk_blk0)) )  goto scanErr;

    // Allocate a buffer large enough to hold one map, rounded to a media block.

    bufferSize = IORound(sizeof(disk_blk0), mediaBlockSize);
    buffer     = IOBufferMemoryDescriptor::withCapacity(
                                           /* capacity      */ bufferSize,
                                           /* withDirection */ kIODirectionIn );
    if ( buffer == 0 )  goto scanErr;

    // Allocate a set to hold the set of media objects representing partitions.

    partitions = OSSet::withCapacity(4);
    if ( partitions == 0 )  goto scanErr;

    // Open the media with read access.

    mediaIsOpen = open(this, 0, kIOStorageAccessReader);
    if ( mediaIsOpen == false )  goto scanErr;

    // Scan the media for FDisk partition map(s).

    do
    {
        // Read the next FDisk map into our buffer.

        status = media->read(this, fdiskBlock * mediaBlockSize, buffer);
        if ( status != kIOReturnSuccess )  goto scanErr;

        fdiskMap = (disk_blk0 *) buffer->getBytesNoCopy();

        // Determine whether the partition map signature is present.

        if ( OSSwapLittleToHostInt16(fdiskMap->signature) != DISK_SIGNATURE )
        {
            goto scanErr;
        }

        // Scan for valid partition entries in the partition map.

        fdiskBlockNext = 0;

        for ( unsigned index = 0; index < DISK_NPART; index++ )
        {
            // Determine whether this is an extended (vs. data) partition.

            if ( isPartitionExtended(fdiskMap->parts + index) )    // (extended)
            {
                // If peer extended partitions exist, we accept only the first.

                if ( fdiskBlockNext == 0 )      // (no peer extended partition)
                {
                    fdiskBlockNext = fdiskBlockExtn +
                                     OSSwapLittleToHostInt32(
                                    /* data */ fdiskMap->parts[index].relsect );

                    if ( fdiskBlockNext * mediaBlockSize >= media->getSize() )
                    {
                        fdiskBlockNext = 0;       // (exceeds confines of media)
                    }
                }
            }
            else if ( isPartitionUsed(fdiskMap->parts + index) )       // (data)
            {
                // Prepare this partition's ID.

                fdiskID = ( fdiskBlock == 0 ) ? (index + 1) : (fdiskID + 1);

                // Determine whether the partition is corrupt (fatal).

                if ( isPartitionCorrupt(
                                   /* partition   */ fdiskMap->parts + index,
                                   /* partitionID */ fdiskID,
                                   /* fdiskBlock  */ fdiskBlock ) )
                {
                    goto scanErr;
                }

                // Determine whether the partition is invalid (skipped).

                if ( isPartitionInvalid(
                                   /* partition   */ fdiskMap->parts + index,
                                   /* partitionID */ fdiskID,
                                   /* fdiskBlock  */ fdiskBlock ) )
                {
                    continue;
                }

                // Create a media object to represent this partition.

                IOMedia * newMedia = instantiateMediaObject(
                                   /* partition   */ fdiskMap->parts + index,
                                   /* partitionID */ fdiskID,
                                   /* fdiskBlock  */ fdiskBlock );

                if ( newMedia )
                {
                    partitions->setObject(newMedia);
                    newMedia->release();
                }
            }
        }

        // Prepare for first extended partition, if any.

        if ( fdiskBlock == 0 )
        {
            fdiskID        = DISK_NPART;
            fdiskBlockExtn = fdiskBlockNext;
        }

    } while ( (fdiskBlock = fdiskBlockNext) );

    // Release our resources.

    close(this);
    buffer->release();

    return partitions;

scanErr:

    // Release our resources.

    if ( mediaIsOpen )  close(this);
    if ( partitions )  partitions->release();
    if ( buffer )  buffer->release();

    return 0;
}