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| author | Michael Halcrow <mhalcrow@google.com> | 2015-04-12 07:43:56 +0300 |
|---|---|---|
| committer | Theodore Ts'o <tytso@mit.edu> | 2015-04-12 07:43:56 +0300 |
| commit | b30ab0e03407d2aa2d9316cba199c757e4bfc8ad (patch) | |
| tree | 900754eb3fe069f90bb5ea2c1df1ed88cf701eb5 /fs/ext4/crypto_policy.c | |
| parent | 9bd8212f981ea6375911fe055382ad7529be5b28 (diff) | |
| download | linux-b30ab0e03407d2aa2d9316cba199c757e4bfc8ad.tar.xz | |
ext4 crypto: add ext4 encryption facilities
On encrypt, we will re-assign the buffer_heads to point to a bounce
page rather than the control_page (which is the original page to write
that contains the plaintext). The block I/O occurs against the bounce
page. On write completion, we re-assign the buffer_heads to the
original plaintext page.
On decrypt, we will attach a read completion callback to the bio
struct. This read completion will decrypt the read contents in-place
prior to setting the page up-to-date.
The current encryption mode, AES-256-XTS, lacks cryptographic
integrity. AES-256-GCM is in-plan, but we will need to devise a
mechanism for handling the integrity data.
Signed-off-by: Michael Halcrow <mhalcrow@google.com>
Signed-off-by: Ildar Muslukhov <ildarm@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Diffstat (limited to 'fs/ext4/crypto_policy.c')
| -rw-r--r-- | fs/ext4/crypto_policy.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/fs/ext4/crypto_policy.c b/fs/ext4/crypto_policy.c index 532b69c0afab..a4bf762b3ba9 100644 --- a/fs/ext4/crypto_policy.c +++ b/fs/ext4/crypto_policy.c @@ -52,6 +52,13 @@ static int ext4_create_encryption_context_from_policy( ctx.format = EXT4_ENCRYPTION_CONTEXT_FORMAT_V1; memcpy(ctx.master_key_descriptor, policy->master_key_descriptor, EXT4_KEY_DESCRIPTOR_SIZE); + if (!ext4_valid_contents_enc_mode(policy->contents_encryption_mode)) { + printk(KERN_WARNING + "%s: Invalid contents encryption mode %d\n", __func__, + policy->contents_encryption_mode); + res = -EINVAL; + goto out; + } ctx.contents_encryption_mode = policy->contents_encryption_mode; ctx.filenames_encryption_mode = policy->filenames_encryption_mode; BUILD_BUG_ON(sizeof(ctx.nonce) != EXT4_KEY_DERIVATION_NONCE_SIZE); @@ -60,6 +67,7 @@ static int ext4_create_encryption_context_from_policy( res = ext4_xattr_set(inode, EXT4_XATTR_INDEX_ENCRYPTION, EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, &ctx, sizeof(ctx), 0); +out: if (!res) ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT); return res; |