18 Dec, 2007
1 commit
-
This was introduced in 4af8e944c22d8af92a7548354a9567250cc1a782
Signed-off-by: Uwe Kleine-König
Cc: David Woodhouse
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
28 Nov, 2007
1 commit
-
Enable expensive bitmap scanning only if DEBUG option is enabled.
The bitmap scanning quite loads the CPU and on my machine the write
throughput of dd if=/dev/zero of=/ocfs2/file bs=1M count=500 conv=sync
improves from 37 MB/s to 45.4 MB/s in local mode...Signed-off-by: Jan Kara
Signed-off-by: Mark Fasheh
13 Nov, 2007
1 commit
-
* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6: (21 commits)
[CIFS] fix oops on second mount to same server when null auth is used
[CIFS] Fix stale mode after readdir when cifsacl specified
[CIFS] add mode to acl conversion helper function
[CIFS] Fix incorrect mode when ACL had deny access control entries
[CIFS] Add uid to key description so krb can handle user mounts
[CIFS] Fix walking out end of cifs dacl
[CIFS] Add upcall files for cifs to use spnego/kerberos
[CIFS] add OIDs for KRB5 and MSKRB5 to ASN1 parsing routines
[CIFS] Register and unregister cifs_spnego_key_type on module init/exit
[CIFS] implement upcalls for SPNEGO blob via keyctl API
[CIFS] allow cifs_calc_signature2 to deal with a zero length iovec
[CIFS] If no Access Control Entries, set mode perm bits to zero
[CIFS] when mount helper missing fix slash wrong direction in share
[CIFS] Don't request too much permission when reading an ACL
[CIFS] enable get mode from ACL when cifsacl mount option specified
[CIFS] ACL support part 8
[CIFS] acl support part 7
[CIFS] acl support part 6
[CIFS] acl support part 6
[CIFS] remove unused funtion compile warning when experimental off
...
03 Nov, 2007
1 commit
-
Add routines to handle upcalls to userspace via keyctl for the purpose
of getting a SPNEGO blob for a particular uid and server combination.Clean up the Makefile a bit and set it up to only compile cifs_spnego
if CONFIG_CIFS_UPCALL is set. Also change CONFIG_CIFS_UPCALL to depend
on CONFIG_KEYS rather than CONFIG_CONNECTOR.cifs_spnego.h defines the communications between kernel and userspace
and is intended to be shared with userspace programs.Signed-off-by: Jeff Layton
Signed-off-by: Steve French
31 Oct, 2007
1 commit
-
Fix links to files in Documentation/* in various Kconfig files
Signed-off-by: Dirk Hohndel
Signed-off-by: Linus Torvalds
20 Oct, 2007
1 commit
-
The jbd-debug file used to be located in /proc/sys/fs/jbd-debug, but
create_proc_entry() does not do lookups on file names that are more that
one directory deep. This causes the entry creation to fail and hence, no
proc file is created.Instead of fixing this on procfs might as well move the jbd2-debug file to
debugfs which would be the preferred location for this kind of tunable.
The new location is now /sys/kernel/debug/jbd/jbd-debug.[akpm@linux-foundation.org: zillions of cleanups]
Signed-off-by: Jose R. Santos
Acked-by: Jan Kara
Cc:
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
18 Oct, 2007
1 commit
-
In pass1 of e2fsck, every inode table in the fileystem is scanned and checked,
regardless of whether it is in use. This is this the most time consuming part
of the filesystem check. The unintialized block group feature can greatly
reduce e2fsck time by eliminating checking of uninitialized inodes.With this feature, there is a a high water mark of used inodes for each block
group. Block and inode bitmaps can be uninitialized on disk via a flag in the
group descriptor to avoid reading or scanning them at e2fsck time. A checksum
of each group descriptor is used to ensure that corruption in the group
descriptor's bit flags does not cause incorrect operation.The feature is enabled through a mkfs option
mke2fs /dev/ -O uninit_groups
A patch adding support for uninitialized block groups to e2fsprogs tools has
been posted to the linux-ext4 mailing list.The patches have been stress tested with fsstress and fsx. In performance
tests testing e2fsck time, we have seen that e2fsck time on ext3 grows
linearly with the total number of inodes in the filesytem. In ext4 with the
uninitialized block groups feature, the e2fsck time is constant, based
solely on the number of used inodes rather than the total inode count.
Since typical ext4 filesystems only use 1-10% of their inodes, this feature can
greatly reduce e2fsck time for users. With performance improvement of 2-20
times, depending on how full the filesystem is.The attached graph shows the major improvements in e2fsck times in filesystems
with a large total inode count, but few inodes in use.In each group descriptor if we have
EXT4_BG_INODE_UNINIT set in bg_flags:
Inode table is not initialized/used in this group. So we can skip
the consistency check during fsck.
EXT4_BG_BLOCK_UNINIT set in bg_flags:
No block in the group is used. So we can skip the block bitmap
verification for this group.We also add two new fields to group descriptor as a part of
uninitialized group patch.__le16 bg_itable_unused; /* Unused inodes count */
__le16 bg_checksum; /* crc16(sb_uuid+group+desc) */bg_itable_unused:
If we have EXT4_BG_INODE_UNINIT not set in bg_flags
then bg_itable_unused will give the offset within
the inode table till the inodes are used. This can be
used by fsck to skip list of inodes that are marked unused.bg_checksum:
Now that we depend on bg_flags and bg_itable_unused to determine
the block and inode usage, we need to make sure group descriptor
is not corrupt. We add checksum to group descriptor to
detect corruption. If the descriptor is found to be corrupt, we
mark all the blocks and inodes in the group used.Signed-off-by: Avantika Mathur
Signed-off-by: Andreas Dilger
Signed-off-by: Mingming Cao
Signed-off-by: Aneesh Kumar K.V
17 Oct, 2007
4 commits
-
Turn Network File Systems into a menuconfig so that it can be disabled at
once.(Note: I added a "default y". If you do not like that, speak up.)
Signed-off-by: Jan Engelhardt
Cc: Trond Myklebust
Cc: "J. Bruce Fields"
Cc: Steven French
Cc: David Howells
Cc: Eric Van Hensbergen
Cc: Neil Brown
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Implement sending of quota messages via netlink interface. The advantage
is that in userspace we can better decide what to do with the message - for
example display a dialogue in your X session or just write the message to
the console. As a bonus, we can get rid of problems with console locking
deep inside filesystem code once we remove the old printing mechanism.Signed-off-by: Jan Kara
Cc: Randy Dunlap
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Since CONFIG_RAMFS is currently hard-selected to "y", and since
Documentation/filesystems/ramfs-rootfs-initramfs.txt reads as follows:"The amount of code required to implement ramfs is tiny, because all the
work is done by the existing Linux caching infrastructure. Basically,
you're mounting the disk cache as a filesystem. Because of this, ramfs is
not an optional component removable via menuconfig, since there would be
negligible space savings."It seems pointless to leave this as a Kconfig entry.
Signed-off-by: Robert P. J. Day
Cc: Al Viro
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Allow disabling DNOTIFY with CONFIG_EMBEDDED=n.
I'm currently running a kernel with dnotify disabled and I haven't run into
any problem. Is there any popular application left that breaks without
dnotify support in the kernel?Note that this patch does not remove dnotify support, it still defaults to
"y", and the help text recommends enabling it.Signed-off-by: Adrian Bunk
Acked-by: Stephen Rothwell
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
16 Oct, 2007
1 commit
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* git://git.linux-nfs.org/pub/linux/nfs-2.6: (131 commits)
NFSv4: Fix a typo in nfs_inode_reclaim_delegation
NFS: Add a boot parameter to disable 64 bit inode numbers
NFS: nfs_refresh_inode should clear cache_validity flags on success
NFS: Fix a connectathon regression in NFSv3 and NFSv4
NFS: Use nfs_refresh_inode() in ops that aren't expected to change the inode
SUNRPC: Don't call xprt_release in call refresh
SUNRPC: Don't call xprt_release() if call_allocate fails
SUNRPC: Fix buggy UDP transmission
[23/37] Clean up duplicate includes in
[2.6 patch] net/sunrpc/rpcb_clnt.c: make struct rpcb_program static
SUNRPC: Use correct type in buffer length calculations
SUNRPC: Fix default hostname created in rpc_create()
nfs: add server port to rpc_pipe info file
NFS: Get rid of some obsolete macros
NFS: Simplify filehandle revalidation
NFS: Ensure that nfs_link() returns a hashed dentry
NFS: Be strict about dentry revalidation when doing exclusive create
NFS: Don't zap the readdir caches upon error
NFS: Remove the redundant nfs_reval_fsid()
NFSv3: Always use directory post-op attributes in nfs3_proc_lookup
...Fix up trivial conflict due to sock_owned_by_user() cleanup manually in
net/sunrpc/xprtsock.c
13 Oct, 2007
1 commit
10 Oct, 2007
2 commits
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Add a dependency on RDMA before enabling SUNRPC_XPRT_RDMA
Yes, "INFINIBAND" also turns on iWARP and other RDMA support.Signed-off-by: Tom Talpey
Signed-off-by: Trond Myklebust -
This file implements the configuration target, protocol template and
constants for the rpcrdma transport framing, for use by the xprtrdma
rpc transport implementation.Signed-off-by: Tom Talpey
Signed-off-by: Trond Myklebust
12 Sep, 2007
1 commit
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Update documentation listing ocfs2 features to reflect the current state of
the file system. Add missing descriptions for some mount options which ocfs2
supports.Signed-off-by: Mark Fasheh
02 Aug, 2007
1 commit
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Signed-off-by: David Woodhouse
23 Jul, 2007
1 commit
20 Jul, 2007
1 commit
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Bruce's patch broke the ability to compile RPCSEC_GSS as a module.
Signed-off-by: Trond Myklebust
18 Jul, 2007
2 commits
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The jbd2-debug file used to be located in /proc/sys/fs/jbd2-debug, but it
incorrectly used create_proc_entry() instead of the sysctl routines, and
no proc entry was ever created.Instead of fixing this we might as well move the jbd2-debug file to
debugfs which would be the preferred location for this kind of tunable.
The new location is now /sys/kernel/debug/jbd2/jbd2-debug.Signed-off-by: Jose R. Santos
Signed-off-by: "Theodore Ts'o" -
Select rpcsec_gss support whenever asked for NFSv4 support. The rfc actually
requires gss, and gss is also the main reason to migrate to v4. We already do
this on the client side.Signed-off-by: "J. Bruce Fields"
Signed-off-by: Neil Brown
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
17 Jul, 2007
1 commit
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* master.kernel.org:/pub/scm/linux/kernel/git/lethal/sh-2.6: (68 commits)
sh: sh-rtc support for SH7709.
sh: Revert __xdiv64_32 size change.
sh: Update r7785rp defconfig.
sh: Export div symbols for GCC 4.2 and ST GCC.
sh: fix race in parallel out-of-tree build
sh: Kill off dead mach.c for hp6xx.
sh: hd64461.h cleanup and added comments.
sh: Update the alignment when 4K stacks are used.
sh: Add a .bss.page_aligned section for 4K stacks.
sh: Don't let SH-4A clobber SH-4 CFLAGS.
sh: Add parport stub for SuperIO ports.
sh: Drop -Wa,-dsp for DSP tuning.
sh: Update dreamcast defconfig.
fb: pvr2fb: A few more __devinit annotations for PCI.
fb: pvr2fb: Fix up section mismatch warnings.
sh: Select IPR-IRQ for SH7091.
sh: Correct __xdiv64_32/div64_32 return value size.
sh: Fix timer-tmu build for SH-3.
sh: Add cpu and mach links to CLEAN_FILES.
sh: Preliminary support for the SH-X3 CPU.
...
15 Jul, 2007
1 commit
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This patchset moves non-filesystem interfaces of v9fs from fs/9p to net/9p.
It moves the transport, packet marshalling and connection layers to net/9p
leaving only the VFS related files in fs/9p. This work is being done in
preparation for in-kernel 9p servers as well as alternate 9p clients (other
than VFS).Signed-off-by: Latchesar Ionkov
Signed-off-by: Eric Van Hensbergen
11 Jul, 2007
3 commits
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Add a "favourlzo" compression mode to jffs2 which tries to
optimise by size but gives lzo an advantage when comparing sizes.
This means the faster lzo algorithm can be preferred when there
isn't much difference in compressed size (the exact threshold can
be changed).Signed-off-by: Richard Purdie
Signed-off-by: David Woodhouse -
Add LZO1X compression/decompression support to jffs2.
LZO's interface doesn't entirely match that required by jffs2 so a
buffer and memcpy is unavoidable.Signed-off-by: Richard Purdie
Signed-off-by: David Woodhouse -
We've seen some evil corruption issues, where the corruption seems to be
introduced after the JFFS2 crc32 is calculated but before the NAND
controller calculates the ECC. So it's in RAM or in the PCI DMA
transfer; not on the flash. Attempt to catch it earlier by (optionally)
reading back from the flash immediately after writing it.Signed-off-by: David Woodhouse
10 Jul, 2007
1 commit
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Convert many spaces to tabs; one or two other minor cosmetic fixes.
Signed-off-by: David Woodhouse
11 Jun, 2007
1 commit
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SH can turn CONFIG_MMU on and off, don't let us get to a state
where hugetlbfs/hugetlbpage gets built when building for nommu.Signed-off-by: Paul Mundt
09 May, 2007
2 commits
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The text removed by the following patch refers to functionality that never
worked, to non-existing documentation file, and to mount options marked as
obsolete in the module.Signed-off-by: Alexander E. Patrakov
Signed-off-by: Adrian Bunk -
REISER_FS /proc option needs to depend on PROC_FS.
fs/reiserfs/procfs.c: In function 'show_super':
fs/reiserfs/procfs.c:134: error: 'reiserfs_proc_info_data_t' has no member named 'max_hash_collisions'
fs/reiserfs/procfs.c:134: error: 'reiserfs_proc_info_data_t' has no member named 'breads'
fs/reiserfs/procfs.c:135: error: 'reiserfs_proc_info_data_t' has no member named 'bread_miss'
fs/reiserfs/procfs.c:135: error: 'reiserfs_proc_info_data_t' has no member named 'search_by_key'
fs/reiserfs/procfs.c:136: error: 'reiserfs_proc_info_data_t' has no member named 'search_by_key_fs_changed'
fs/reiserfs/procfs.c:136: error: 'reiserfs_proc_info_data_t' has no member named 'search_by_key_restarted'
fs/reiserfs/procfs.c:137: error: 'reiserfs_proc_info_data_t' has no member named 'insert_item_restarted'
fs/reiserfs/procfs.c:137: error: 'reiserfs_proc_info_data_t' has no member named 'paste_into_item_restarted'
fs/reiserfs/procfs.c:138: error: 'reiserfs_proc_info_data_t' has no member named 'cut_from_item_restarted'
fs/reiserfs/procfs.c:139: error: 'reiserfs_proc_info_data_t' has no member named 'delete_solid_item_restarted'
fs/reiserfs/procfs.c:139: error: 'reiserfs_proc_info_data_t' has no member named 'delete_item_restarted'
fs/reiserfs/procfs.c:140: error: 'reiserfs_proc_info_data_t' has no member named 'leaked_oid'
fs/reiserfs/procfs.c:140: error: 'reiserfs_proc_info_data_t' has no member named 'leaves_removable'
fs/reiserfs/procfs.c: In function 'show_per_level':
fs/reiserfs/procfs.c:184: error: 'reiserfs_proc_info_data_t' has no member named 'balance_at'
fs/reiserfs/procfs.c:185: error: 'reiserfs_proc_info_data_t' has no member named 'sbk_read_at'
fs/reiserfs/procfs.c:186: error: 'reiserfs_proc_info_data_t' has no member named 'sbk_fs_changed'
fs/reiserfs/procfs.c:187: error: 'reiserfs_proc_info_data_t' has no member named 'sbk_restarted'
fs/reiserfs/procfs.c:188: error: 'reiserfs_proc_info_data_t' has no member named 'free_at'
fs/reiserfs/procfs.c:189: error: 'reiserfs_proc_info_data_t' has no member named 'items_at'
fs/reiserfs/procfs.c:190: error: 'reiserfs_proc_info_data_t' has no member named 'can_node_be_removed'
fs/reiserfs/procfs.c:191: error: 'reiserfs_proc_info_data_t' has no member named 'lnum'
fs/reiserfs/procfs.c:192: error: 'reiserfs_proc_info_data_t' has no member named 'rnum'
fs/reiserfs/procfs.c:193: error: 'reiserfs_proc_info_data_t' has no member named 'lbytes'
fs/reiserfs/procfs.c:194: error: 'reiserfs_proc_info_data_t' has no member named 'rbytes'
fs/reiserfs/procfs.c:195: error: 'reiserfs_proc_info_data_t' has no member named 'get_neighbors'
fs/reiserfs/procfs.c:196: error: 'reiserfs_proc_info_data_t' has no member named 'get_neighbors_restart'
fs/reiserfs/procfs.c:197: error: 'reiserfs_proc_info_data_t' has no member named 'need_l_neighbor'
fs/reiserfs/procfs.c:197: error: 'reiserfs_proc_info_data_t' has no member named 'need_r_neighbor'
fs/reiserfs/procfs.c: In function 'show_bitmap':
fs/reiserfs/procfs.c:224: error: 'reiserfs_proc_info_data_t' has no member named 'free_block'
fs/reiserfs/procfs.c:225: error: 'reiserfs_proc_info_data_t' has no member named 'scan_bitmap'
fs/reiserfs/procfs.c:226: error: 'reiserfs_proc_info_data_t' has no member named 'scan_bitmap'
fs/reiserfs/procfs.c:227: error: 'reiserfs_proc_info_data_t' has no member named 'scan_bitmap'
fs/reiserfs/procfs.c:228: error: 'reiserfs_proc_info_data_t' has no member named 'scan_bitmap'
fs/reiserfs/procfs.c:229: error: 'reiserfs_proc_info_data_t' has no member named 'scan_bitmap'
fs/reiserfs/procfs.c:230: error: 'reiserfs_proc_info_data_t' has no member named 'scan_bitmap'
fs/reiserfs/procfs.c:230: error: 'reiserfs_proc_info_data_t' has no member named 'scan_bitmap'
fs/reiserfs/procfs.c: In function 'show_journal':
fs/reiserfs/procfs.c:384: error: 'reiserfs_proc_info_data_t' has no member named 'journal'
fs/reiserfs/procfs.c:385: error: 'reiserfs_proc_info_data_t' has no member named 'journal'
fs/reiserfs/procfs.c:386: error: 'reiserfs_proc_info_data_t' has no member named 'journal'
fs/reiserfs/procfs.c:387: error: 'reiserfs_proc_info_data_t' has no member named 'journal'
fs/reiserfs/procfs.c:388: error: 'reiserfs_proc_info_data_t' has no member named 'journal'
fs/reiserfs/procfs.c:389: error: 'reiserfs_proc_info_data_t' has no member named 'journal'
fs/reiserfs/procfs.c:390: error: 'reiserfs_proc_info_data_t' has no member named 'journal'
fs/reiserfs/procfs.c:391: error: 'reiserfs_proc_info_data_t' has no member named 'journal'
fs/reiserfs/procfs.c:392: error: 'reiserfs_proc_info_data_t' has no member named 'journal'
fs/reiserfs/procfs.c:393: error: 'reiserfs_proc_info_data_t' has no member named 'journal'
fs/reiserfs/procfs.c:394: error: 'reiserfs_proc_info_data_t' has no member named 'journal'
fs/reiserfs/procfs.c:395: error: 'reiserfs_proc_info_data_t' has no member named 'journal'
fs/reiserfs/procfs.c:395: error: 'reiserfs_proc_info_data_t' has no member named 'journal'
fs/reiserfs/procfs.c:395: error: 'reiserfs_proc_info_data_t' has no member named 'journal'
fs/reiserfs/procfs.c: In function 'reiserfs_proc_info_init':
fs/reiserfs/procfs.c:504: warning: implicit declaration of function '__PINFO'
fs/reiserfs/procfs.c:504: error: request for member 'lock' in something not a structure or union
fs/reiserfs/procfs.c: In function 'reiserfs_proc_info_done':
fs/reiserfs/procfs.c:544: error: request for member 'lock' in something not a structure or union
fs/reiserfs/procfs.c:545: error: request for member 'exiting' in something not a structure or union
fs/reiserfs/procfs.c:546: error: request for member 'lock' in something not a structure or unionSigned-off-by: Randy Dunlap
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
05 May, 2007
1 commit
-
* git://git.linux-nfs.org/pub/linux/nfs-2.6: (28 commits)
NFS: Fix a compile glitch on 64-bit systems
NFS: Clean up nfs_create_request comments
spkm3: initialize hash
spkm3: remove bad kfree, unnecessary export
spkm3: fix spkm3's use of hmac
NFS4: invalidate cached acl on setacl
NFS: Fix directory caching problem - with test case and patch.
NFS: Set meaningful value for fattr->time_start in readdirplus results.
NFS: Added support to turn off the NFSv3 READDIRPLUS RPC.
SUNRPC: RPC client should retry with different versions of rpcbind
SUNRPC: remove old portmapper
NFS: switch NFSROOT to use new rpcbind client
SUNRPC: switch the RPC server to use the new rpcbind registration API
SUNRPC: switch socket-based RPC transports to use rpcbind
SUNRPC: introduce rpcbind: replacement for in-kernel portmapper
SUNRPC: Eliminate side effects from rpc_malloc
SUNRPC: RPC buffer size estimates are too large
NLM: Shrink the maximum request size of NLM4 requests
NFS: Use pgoff_t in structures and functions that pass page cache offsets
NFS: Clean up nfs_sync_mapping_wait()
...
03 May, 2007
1 commit
-
Make miscellaneous fixes to AFS and AF_RXRPC:
(*) Make AF_RXRPC select KEYS rather than RXKAD or AFS_FS in Kconfig.
(*) Don't use FS_BINARY_MOUNTDATA.
(*) Remove a done 'TODO' item in a comemnt on afs_get_sb().
(*) Don't pass a void * as the page pointer argument of kmap_atomic() as this
breaks on m68k. Patch from Geert Uytterhoeven .(*) Use match_*() functions rather than doing my own parsing.
Signed-off-by: David Howells
Signed-off-by: David S. Miller
01 May, 2007
1 commit
-
Signed-off-by: Chuck Lever
Signed-off-by: Trond Myklebust
28 Apr, 2007
1 commit
-
Fixes for various arch compilation problems:
(*) Missing module exports.
(*) Variable name collision when rxkad and af_rxrpc both built in
(rxrpc_debug).(*) Large constant representation problem (AFS_UUID_TO_UNIX_TIME).
(*) Configuration dependencies.
(*) printk() format warnings.
Signed-off-by: David Howells
Signed-off-by: David S. Miller
27 Apr, 2007
2 commits
-
Delete the old RxRPC code as it's now no longer used.
Signed-off-by: David Howells
Signed-off-by: David S. Miller -
Make the in-kernel AFS filesystem use AF_RXRPC instead of the old RxRPC code.
Signed-off-by: David Howells
Signed-off-by: David S. Miller
18 Feb, 2007
1 commit
-
Unmaintained for years, few if any users.
Signed-off-by: Jeff Garzik
14 Feb, 2007
2 commits
-
* master.kernel.org:/pub/scm/linux/kernel/git/sfrench/cifs-2.6:
[CIFS] on reconnect to Samba - reset the unix capabilities
[CIFS] Allow update of EOF on remote extend of file
[CIFS] POSIX CIFS Extensions (continued) - POSIX Open
[CIFS] Additional POSIX CIFS Extensions infolevels -
After temporary server or network failure and reconneciton, we were not
resending the unix capabilities via SetFSInfo - which confused Samba posix
byte range locking code.Discovered by jra
Signed-off-by: Steve French
13 Feb, 2007
1 commit
-
This is the transport code for public key functionality in eCryptfs. It
manages encryption/decryption request queues with a transport mechanism.
Currently, netlink is the only implemented transport.Each inode has a unique File Encryption Key (FEK). Under passphrase, a File
Encryption Key Encryption Key (FEKEK) is generated from a salt/passphrase
combo on mount. This FEKEK encrypts each FEK and writes it into the header of
each file using the packet format specified in RFC 2440. This is all
symmetric key encryption, so it can all be done via the kernel crypto API.These new patches introduce public key encryption of the FEK. There is no
asymmetric key encryption support in the kernel crypto API, so eCryptfs pushes
the FEK encryption and decryption out to a userspace daemon. After
considering our requirements and determining the complexity of using various
transport mechanisms, we settled on netlink for this communication.eCryptfs stores authentication tokens into the kernel keyring. These tokens
correlate with individual keys. For passphrase mode of operation, the
authentication token contains the symmetric FEKEK. For public key, the
authentication token contains a PKI type and an opaque data blob managed by
individual PKI modules in userspace.Each user who opens a file under an eCryptfs partition mounted in public key
mode must be running a daemon. That daemon has the user's credentials and has
access to all of the keys to which the user should have access. The daemon,
when started, initializes the pluggable PKI modules available on the system
and registers itself with the eCryptfs kernel module. Userspace utilities
register public key authentication tokens into the user session keyring.
These authentication tokens correlate key signatures with PKI modules and PKI
blobs. The PKI blobs contain PKI-specific information necessary for the PKI
module to carry out asymmetric key encryption and decryption.When the eCryptfs module parses the header of an existing file and finds a Tag
1 (Public Key) packet (see RFC 2440), it reads in the public key identifier
(signature). The asymmetrically encrypted FEK is in the Tag 1 packet;
eCryptfs puts together a decrypt request packet containing the signature and
the encrypted FEK, then it passes it to the daemon registered for the
current->euid via a netlink unicast to the PID of the daemon, which was
registered at the time the daemon was started by the user.The daemon actually just makes calls to libecryptfs, which implements request
packet parsing and manages PKI modules. libecryptfs grabs the public key
authentication token for the given signature from the user session keyring.
This auth tok tells libecryptfs which PKI module should receive the request.
libecryptfs then makes a decrypt() call to the PKI module, and it passes along
the PKI block from the auth tok. The PKI uses the blob to figure out how it
should decrypt the data passed to it; it performs the decryption and passes
the decrypted data back to libecryptfs. libecryptfs then puts together a
reply packet with the decrypted FEK and passes that back to the eCryptfs
module.The eCryptfs module manages these request callouts to userspace code via
message context structs. The module maintains an array of message context
structs and places the elements of the array on two lists: a free and an
allocated list. When eCryptfs wants to make a request, it moves a msg ctx
from the free list to the allocated list, sets its state to pending, and fires
off the message to the user's registered daemon.When eCryptfs receives a netlink message (via the callback), it correlates the
msg ctx struct in the alloc list with the data in the message itself. The
msg->index contains the offset of the array of msg ctx structs. It verifies
that the registered daemon PID is the same as the PID of the process that sent
the message. It also validates a sequence number between the received packet
and the msg ctx. Then, it copies the contents of the message (the reply
packet) into the msg ctx struct, sets the state in the msg ctx to done, and
wakes up the process that was sleeping while waiting for the reply.The sleeping process was whatever was performing the sys_open(). This process
originally called ecryptfs_send_message(); it is now in
ecryptfs_wait_for_response(). When it wakes up and sees that the msg ctx
state was set to done, it returns a pointer to the message contents (the reply
packet) and returns. If all went well, this packet contains the decrypted
FEK, which is then copied into the crypt_stat struct, and life continues as
normal.The case for creation of a new file is very similar, only instead of a decrypt
request, eCryptfs sends out an encrypt request.> - We have a great clod of key mangement code in-kernel. Why is that
> not suitable (or growable) for public key management?eCryptfs uses Howells' keyring to store persistent key data and PKI state
information. It defers public key cryptographic transformations to userspace
code. The userspace data manipulation request really is orthogonal to key
management in and of itself. What eCryptfs basically needs is a secure way to
communicate with a particular daemon for a particular task doing a syscall,
based on the UID. Nothing running under another UID should be able to access
that channel of communication.> - Is it appropriate that new infrastructure for public key
> management be private to a particular fs?The messaging.c file contains a lot of code that, perhaps, could be extracted
into a separate kernel service. In essence, this would be a sort of
request/reply mechanism that would involve a userspace daemon. I am not aware
of anything that does quite what eCryptfs does, so I was not aware of any
existing tools to do just what we wanted.> What happens if one of these daemons exits without sending a quit
> message?There is a stale uidpid association in the hash table for that user. When
the user registers a new daemon, eCryptfs cleans up the old association and
generates a new one. See ecryptfs_process_helo().> - _why_ does it use netlink?
Netlink provides the transport mechanism that would minimize the complexity of
the implementation, given that we can have multiple daemons (one per user). I
explored the possibility of using relayfs, but that would involve having to
introduce control channels and a protocol for creating and tearing down
channels for the daemons. We do not have to worry about any of that with
netlink.Signed-off-by: Michael Halcrow
Cc: David Howells
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
