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| author | Eric Biggers <ebiggers@google.com> | 2020-05-06 14:15:07 -0700 |
|---|---|---|
| committer | Eric Biggers <ebiggers@google.com> | 2020-05-14 11:44:58 -0700 |
| commit | 6be68d89b4d524dde1476be8f895a69cc08237ee (patch) | |
| tree | 330325437da0ba1e193b23584b7673ff33b1a573 | |
| parent | 8711e464f7dfcd3c18cbbbfa95127bc8868e0430 (diff) | |
| download | hikey-linaro-6be68d89b4d524dde1476be8f895a69cc08237ee.tar.gz | |
ANDROID: fscrypt: set dun_bytes more precisely
Make fscrypt set dun_bytes to only what it actually needs, so that it
can make use of inline crypto hardware in more cases.
Bug: 144046242
Bug: 153512828
Change-Id: I36f90ea6b64ef51a9d58ffb069d2cba74965c239
Signed-off-by: Eric Biggers <ebiggers@google.com>
| -rw-r--r-- | fs/crypto/inline_crypt.c | 17 |
1 files changed, 12 insertions, 5 deletions
diff --git a/fs/crypto/inline_crypt.c b/fs/crypto/inline_crypt.c index 976617112d52..f96e2972a003 100644 --- a/fs/crypto/inline_crypt.c +++ b/fs/crypto/inline_crypt.c @@ -44,13 +44,20 @@ static void fscrypt_get_devices(struct super_block *sb, int num_devs, static unsigned int fscrypt_get_dun_bytes(const struct fscrypt_info *ci) { - unsigned int dun_bytes = 8; + struct super_block *sb = ci->ci_inode->i_sb; + unsigned int flags = fscrypt_policy_flags(&ci->ci_policy); + int ino_bits = 64, lblk_bits = 64; - if (fscrypt_policy_flags(&ci->ci_policy) & - FSCRYPT_POLICY_FLAG_DIRECT_KEY) - dun_bytes += FS_KEY_DERIVATION_NONCE_SIZE; + if (flags & FSCRYPT_POLICY_FLAG_DIRECT_KEY) + return offsetofend(union fscrypt_iv, nonce); - return dun_bytes; + if (flags & FSCRYPT_POLICY_FLAG_IV_INO_LBLK_64) + return sizeof(__le64); + + /* Default case: IVs are just the file logical block number */ + if (sb->s_cop->get_ino_and_lblk_bits) + sb->s_cop->get_ino_and_lblk_bits(sb, &ino_bits, &lblk_bits); + return DIV_ROUND_UP(lblk_bits, 8); } /* Enable inline encryption for this file if supported. */ |