linux-toradex.git/fs/ecryptfs/ecryptfs_kernel.h, branch v2.6.27.42

eCryptfs: Make all persistent file opens delayed

2008-07-24T17:47:31+00:00

There is no good reason to immediately open the lower file, and that can
cause problems with files that the user does not intend to immediately
open, such as device nodes.

This patch removes the persistent file open from the interpose step and
pushes that to the locations where eCryptfs really does need the lower
persistent file, such as just before reading or writing the metadata
stored in the lower file header.

Two functions are jumping to out_dput when they should just be jumping to
out on error paths.  This patch also fixes these.

Signed-off-by: Michael Halcrow 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

eCryptfs: do not try to open device files on mknod

2008-07-24T17:47:31+00:00

When creating device nodes, eCryptfs needs to delay actually opening the lower
persistent file until an application tries to open.  Device handles may not be
backed by anything when they first come into existence.

[Valdis.Kletnieks@vt.edu: build fix]
Signed-off-by: Michael Halcrow 
Cc: 
Signed-off-by: Linus Torvalds

eCryptfs: Privileged kthread for lower file opens

2008-07-24T17:47:30+00:00

eCryptfs would really like to have read-write access to all files in the
lower filesystem.  Right now, the persistent lower file may be opened
read-only if the attempt to open it read-write fails.  One way to keep
from having to do that is to have a privileged kthread that can open the
lower persistent file on behalf of the user opening the eCryptfs file;
this patch implements this functionality.

This patch will properly allow a less-privileged user to open the eCryptfs
file, followed by a more-privileged user opening the eCryptfs file, with
the first user only being able to read and the second user being able to
both read and write.  eCryptfs currently does this wrong; it will wind up
calling vfs_write() on a file that was opened read-only.  This is fixed in
this patch.

Signed-off-by: Michael Halcrow 
Cc: Dave Kleikamp 
Cc: Serge Hallyn 
Cc: Eric Sandeen 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

eCryptfs: remove unnecessary page decrypt call

2008-06-06T18:29:09+00:00

The page decrypt calls in ecryptfs_write() are both pointless and buggy.
Pointless because ecryptfs_get_locked_page() has already brought the page
up to date, and buggy because prior mmap writes will just be blown away by
the decrypt call.

This patch also removes the declaration of a now-nonexistent function
ecryptfs_write_zeros().

Thanks to Eric Sandeen and David Kleikamp for helping to track this
down.

Eric said:

   fsx w/ mmap dies quickly ( < 100 ops) without this, and survives
   nicely (to millions of ops+) with it in place.

Signed-off-by: Michael Halcrow 
Cc: Eric Sandeen 
Cc: Dave Kleikamp 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

eCryptfs: make key module subsystem respect namespaces

2008-04-29T15:06:07+00:00

Make eCryptfs key module subsystem respect namespaces.

Since I will be removing the netlink interface in a future patch, I just made
changes to the netlink.c code so that it will not break the build.  With my
recent patches, the kernel module currently defaults to the device handle
interface rather than the netlink interface.

[akpm@linux-foundation.org: export free_user_ns()]
Signed-off-by: Michael Halcrow 
Acked-by: Serge Hallyn 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

eCryptfs: integrate eCryptfs device handle into the module.

2008-04-29T15:06:07+00:00

Update the versioning information.  Make the message types generic.  Add an
outgoing message queue to the daemon struct.  Make the functions to parse
and write the packet lengths available to the rest of the module.  Add
functions to create and destroy the daemon structs.  Clean up some of the
comments and make the code a little more consistent with itself.

[akpm@linux-foundation.org: printk fixes]
Signed-off-by: Michael Halcrow 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

ecryptfs: replace remaining FUNCTION occurrences

2008-04-29T15:06:06+00:00

__FUNCTION__ is gcc-specific, use __func__

Signed-off-by: Harvey Harrison 
Cc: Michael Halcrow 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

ecryptfs: check for existing key_tfm at mount time

2008-02-06T18:41:13+00:00

Jeff Moyer pointed out that a mount; umount loop of ecryptfs, with the same
cipher & other mount options, created a new ecryptfs_key_tfm_cache item
each time, and the cache could grow quite large this way.

Looking at this with mhalcrow, we saw that ecryptfs_parse_options()
unconditionally called ecryptfs_add_new_key_tfm(), which is what was adding
these items.

Refactor ecryptfs_get_tfm_and_mutex_for_cipher_name() to create a new
helper function, ecryptfs_tfm_exists(), which checks for the cipher on the
cached key_tfm_list, and sets a pointer to it if it exists.  This can then
be called from ecryptfs_parse_options(), and new key_tfm's can be added
only when a cached one is not found.

With list locking changes suggested by akpm.

Signed-off-by: Eric Sandeen 
Cc: Michael Halcrow 
Cc: Jeff Moyer 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

eCryptfs: change the type of cipher_code from u16 to u8