Hi,
These series improve QEMU support for DMG image files:
- Images which are not multiples of a block size (512) are now properly
recognized ("properly detect the UDIF trailer").
- Block descriptors stored in the XML plist section rather than the Resource
Fork are now recognized ("process XML plists").
- The virtual (uncompressed) image size is now advertised ("set virtual size to
a non-zero value").
- Files which have a different data offsets are now properly handled ("fix
sector data offset calculation").
- bzip2-compressed chunks can now be read ("support bzip2 block entry types").
This adds a new --enable-bzip2 option.
- Files with a large all-zeroes data chunk do not trip an error anymore
("improve zeroes handling").
The XML plist patch depends on these refactorings (which add no new
functionality):
block/dmg: extract mish block decoding functionality
block/dmg: extract processing of resource forks
block/dmg: process a buffer instead of reading ints
Finally there is this patch which avoids a DoS (large memory allocation) due to
a missing check on untrusted data:
block/dmg: validate chunk size to avoid overflow
These patches were tested against disk images, but since DMG files are also used
for installers, I used those too. The following files pass these patches:
- filename + source; real size in bytes; publication date. (additional info:
whether BLXX is stored in XML plists or a resource fork; compression method)
- espgs-7.05.5-0.ppc.dmg[1] 5593786 2002-09 (rsrc fork, zlib, sector
offsets start at 0)
- Wireshark 1.12.2 Intel 64.dmg[2] 26375047 2014-11 (xml, zlib)
- tuxpaint-0.9.15-macosx.dmg[3] 9022458 2005-11 (rsrc fork, zlib)
- vlc-2.1.5.dmg[4] 33519849 2014-07 (xml, bzlib)
- OS X Yosemite.dmg 5189100314 2014-10 (xml, bzlib)
- InstallESD.dmg (in prev. image) 5164763151 2014-10 (xml, zlib; data offset
is non-zero)
For these above files, I executed `qemu-img info foo.dmg` to verify that there
is
no EINVAL error and `qemu-img convert -f dmg -O raw foo.dmg foo.raw` to check
whether reading works. The resulting `foo.raw` was then compared against
`foo.img` as generated by `dmg2img foo.dmg`.
This file was tested and 'qemu-img info' works properly, but conversion failed
because the Apple Data Compression (ADC) format is not supported[5].
- NetBoot9.dmg[6] 534884900 2003-09 (rsrc fork, adc)
These patches (rebased against current master) can be found at:
https://git.lekensteyn.nl/peter/qemu/log/?h=block-dmg-2.3
(development and testing was done against v2.2.0, branch block-dmg-2.2)
Kind regards,
Peter
[1]: http://sourceforge.net/projects/espgs/files/espgs/7.05.5/
[2]: https://www.wireshark.org/download/osx/
[3]: http://sourceforge.net/projects/tuxpaint/files/tuxpaint/0.9.15/
[4]: http://download.videolan.org/pub/videolan/vlc/2.1.5/macosx/
[5]: https://bugzilla.redhat.com/show_bug.cgi?id=1058132
[6]:
http://download.info.apple.com/Mac_OS_X/693-4445.20030912.gnr39/NetBoot9.dmg
--
Peter Wu (10):
block/dmg: properly detect the UDIF trailer
block/dmg: extract mish block decoding functionality
block/dmg: extract processing of resource forks
block/dmg: process a buffer instead of reading ints
block/dmg: validate chunk size to avoid overflow
block/dmg: process XML plists
block/dmg: set virtual size to a non-zero value
block/dmg: fix sector data offset calculation
block/dmg: support bzip2 block entry types
block/dmg: improve zeroes handling
block/dmg.c | 475 +++++++++++++++++++++++++++++++++++++++++++++---------------
configure | 31 ++++
2 files changed, 390 insertions(+), 116 deletions(-)
--
2.2.1
