On Wed, Jul 12, 2017 at 02:00:35PM -0700, Eric Biggers wrote:
> From: Eric Biggers <ebigg...@google.com>
>
> Since v2 encryption policies are opt-in, take the opportunity to also
> drop support for the legacy filesystem-specific key description prefixes
> "ext4:", "f2fs:", and "ubifs:", instead requiring the generic prefix
> "fscrypt:". The generic prefix is preferred since it works for all
> filesystems. Also there is a performance benefit from not having to
> search the keyrings twice.
>
> The old prefixes remain supported for v1 encryption policies.
>
> Signed-off-by: Eric Biggers <ebigg...@google.com>
Reviewed-by: Michael Halcrow <mhalc...@google.com>
> ---
> fs/crypto/fscrypt_private.h | 3 +--
> fs/crypto/keyinfo.c | 16 ++++------------
> fs/crypto/policy.c | 2 +-
> 3 files changed, 6 insertions(+), 15 deletions(-)
>
> diff --git a/fs/crypto/fscrypt_private.h b/fs/crypto/fscrypt_private.h
> index 4b158717a8c3..201906ff7033 100644
> --- a/fs/crypto/fscrypt_private.h
> +++ b/fs/crypto/fscrypt_private.h
> @@ -167,8 +167,7 @@ extern struct page *fscrypt_alloc_bounce_page(struct
> fscrypt_ctx *ctx,
> gfp_t gfp_flags);
>
> /* keyinfo.c */
> -extern int fscrypt_compute_key_hash(const struct inode *inode,
> - const struct fscrypt_policy *policy,
> +extern int fscrypt_compute_key_hash(const struct fscrypt_policy *policy,
> u8 hash[FSCRYPT_KEY_HASH_SIZE]);
> extern void __exit fscrypt_essiv_cleanup(void);
>
> diff --git a/fs/crypto/keyinfo.c b/fs/crypto/keyinfo.c
> index bf60e76f9599..e20b5e85c1b3 100644
> --- a/fs/crypto/keyinfo.c
> +++ b/fs/crypto/keyinfo.c
> @@ -385,8 +385,7 @@ find_and_lock_keyring_key(const char *prefix,
> }
>
> static struct fscrypt_master_key *
> -load_master_key_from_keyring(const struct inode *inode,
> - const u8 descriptor[FS_KEY_DESCRIPTOR_SIZE],
> +load_master_key_from_keyring(const u8 descriptor[FS_KEY_DESCRIPTOR_SIZE],
> unsigned int min_keysize)
> {
> struct key *keyring_key;
> @@ -395,11 +394,6 @@ load_master_key_from_keyring(const struct inode *inode,
>
> keyring_key = find_and_lock_keyring_key(FS_KEY_DESC_PREFIX, descriptor,
> min_keysize, &payload);
> - if (keyring_key == ERR_PTR(-ENOKEY) && inode->i_sb->s_cop->key_prefix) {
> - keyring_key = find_and_lock_keyring_key(
> - inode->i_sb->s_cop->key_prefix,
> - descriptor, min_keysize, &payload);
> - }
> if (IS_ERR(keyring_key))
> return ERR_CAST(keyring_key);
>
> @@ -441,8 +435,7 @@ find_or_create_master_key(const struct inode *inode,
> /*
> * The needed master key isn't in memory yet. Load it from the keyring.
> */
> - master_key = load_master_key_from_keyring(inode,
> - ctx->master_key_descriptor,
> + master_key = load_master_key_from_keyring(ctx->master_key_descriptor,
> min_keysize);
> if (IS_ERR(master_key))
> return master_key;
> @@ -676,8 +669,7 @@ void __exit fscrypt_essiv_cleanup(void)
> crypto_free_shash(essiv_hash_tfm);
> }
>
> -int fscrypt_compute_key_hash(const struct inode *inode,
> - const struct fscrypt_policy *policy,
> +int fscrypt_compute_key_hash(const struct fscrypt_policy *policy,
> u8 hash[FSCRYPT_KEY_HASH_SIZE])
> {
> struct fscrypt_master_key *k;
> @@ -691,7 +683,7 @@ int fscrypt_compute_key_hash(const struct inode *inode,
> max(available_modes[policy->contents_encryption_mode].keysize,
> available_modes[policy->filenames_encryption_mode].keysize);
>
> - k = load_master_key_from_keyring(inode, policy->master_key_descriptor,
> + k = load_master_key_from_keyring(policy->master_key_descriptor,
> min_keysize);
> if (IS_ERR(k))
> return PTR_ERR(k);
> diff --git a/fs/crypto/policy.c b/fs/crypto/policy.c
> index 7661c66a3533..cd8c9c7cc9a9 100644
> --- a/fs/crypto/policy.c
> +++ b/fs/crypto/policy.c
> @@ -117,7 +117,7 @@ int fscrypt_ioctl_set_policy(struct file *filp, const
> void __user *arg)
> pr_warn_once("%s (pid %d) is setting less secure v0 encryption
> policy; recommend upgrading to v2.\n",
> current->comm, current->pid);
> } else {
> - ret = fscrypt_compute_key_hash(inode, &policy, key_hash);
> + ret = fscrypt_compute_key_hash(&policy, key_hash);
> if (ret)
> return ret;
> }
> --
> 2.13.2.932.g7449e964c-goog
>
