linux.git/fs/ecryptfs/ecryptfs_kernel.h, branch v2.6.39

eCryptfs: Handle failed metadata read in lookup

2011-04-25T23:45:06+00:00

When failing to read the lower file's crypto metadata during a lookup,
eCryptfs must continue on without throwing an error. For example, there
may be a plaintext file in the lower mount point that the user wants to
delete through the eCryptfs mount.

If an error is encountered while reading the metadata in lookup(), the
eCryptfs inode's size could be incorrect. We must be sure to reread the
plaintext inode size from the metadata when performing an open() or
setattr(). The metadata is already being read in those paths, so this
adds minimal performance overhead.

This patch introduces a flag which will track whether or not the
plaintext inode size has been read so that an incorrect i_size can be
fixed in the open() or setattr() paths.

https://bugs.launchpad.net/bugs/509180

Cc: 
Signed-off-by: Tyler Hicks

eCryptfs: Add reference counting to lower files

2011-04-25T23:32:37+00:00

For any given lower inode, eCryptfs keeps only one lower file open and
multiplexes all eCryptfs file operations through that lower file. The
lower file was considered "persistent" and stayed open from the first
lookup through the lifetime of the inode.

This patch keeps the notion of a single, per-inode lower file, but adds
reference counting around the lower file so that it is closed when not
currently in use. If the reference count is at 0 when an operation (such
as open, create, etc.) needs to use the lower file, a new lower file is
opened. Since the file is no longer persistent, all references to the
term persistent file are changed to lower file.

Locking is added around the sections of code that opens the lower file
and assign the pointer in the inode info, as well as the code the fputs
the lower file when all eCryptfs users are done with it.

This patch is needed to fix issues, when mounted on top of the NFSv3
client, where the lower file is left silly renamed until the eCryptfs
inode is destroyed.

Signed-off-by: Tyler Hicks

eCryptfs: verify authentication tokens before their use

2011-03-28T06:49:41+00:00

Authentication tokens content may change if another requestor calls the
update() method of the corresponding key. The new function
ecryptfs_verify_auth_tok_from_key() retrieves the authentication token from
the provided key and verifies if it is still valid before being used to
encrypt or decrypt an eCryptfs file.

Signed-off-by: Roberto Sassu 
[tyhicks: Minor formatting changes]
Signed-off-by: Tyler Hicks

eCryptfs: modified size of keysig in the ecryptfs_key_sig structure

2011-03-28T06:49:40+00:00

The size of the 'keysig' array is incremented of one byte in order to make
room for the NULL character. The 'keysig' variable is used, in the function
ecryptfs_generate_key_packet_set(), to find an authentication token with
the given signature and is printed a debug message if it cannot be
retrieved.

Signed-off-by: Roberto Sassu 
Signed-off-by: Tyler Hicks

eCryptfs: removed num_global_auth_toks from ecryptfs_mount_crypt_stat

2011-03-28T06:49:39+00:00

This patch removes the 'num_global_auth_toks' field of the
ecryptfs_mount_crypt_stat structure, used to count the number of items in
the 'global_auth_tok_list' list. This variable is not needed because there
are no checks based upon it.

Signed-off-by: Roberto Sassu 
Signed-off-by: Tyler Hicks

ecryptfs: modify write path to encrypt page in writepage

2011-03-28T06:47:45+00:00

Change the write path to encrypt the data only when the page is written to
disk in ecryptfs_writepage. Previously, ecryptfs encrypts the page in
ecryptfs_write_end which means that if there are multiple write requests to
the same page, ecryptfs ends up re-encrypting that page over and over again.
This patch minimizes the number of encryptions needed.

Signed-off-by: Thieu Le 
[tyhicks: Changed NULL .drop_inode sop pointer to generic_drop_inode]
Signed-off-by: Tyler Hicks

eCryptfs: Remove ECRYPTFS_NEW_FILE crypt stat flag

2011-03-28T06:47:44+00:00

Now that grow_file() is not called in the ecryptfs_create() path, the
ECRYPTFS_NEW_FILE flag is no longer needed. It helped
ecryptfs_readpage() know not to decrypt zeroes that were read from the
lower file in the grow_file() path.

Signed-off-by: Tyler Hicks

eCryptfs: Handle NULL nameidata pointers

2011-02-21T20:45:57+00:00

Allow for NULL nameidata pointers in eCryptfs create, lookup, and
d_revalidate functions.

Signed-off-by: Tyler Hicks

fs/ecryptfs: Add printf format/argument verification and fix fallout

2011-01-17T19:01:23+00:00

Add __attribute__((format... to __ecryptfs_printk
Make formats and arguments match.
Add casts to (unsigned long long) for %llu.

Signed-off-by: Joe Perches 
[tyhicks: 80 columns cleanup and fixed typo]
Signed-off-by: Tyler Hicks

ecryptfs: moved ECRYPTFS_SUPER_MAGIC definition to linux/magic.h

2011-01-17T16:44:31+00:00

The definition of ECRYPTFS_SUPER_MAGIC has been moved to the include
file 'linux/magic.h' to become available to other kernel subsystems.

Signed-off-by: Roberto Sassu 
Signed-off-by: Tyler Hicks