From: Michael Halcrow Subject: Re: [PATCH 6/6] fscrypt: for v2 policies, support "fscrypt:" key prefix only Date: Mon, 17 Jul 2017 10:54:52 -0700 Message-ID: <20170717175452.GB32282@google.com> References: <20170712210035.51534-1-ebiggers3@gmail.com> <20170712210035.51534-7-ebiggers3@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-fscrypt@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-mtd@lists.infradead.org, linux-crypto@vger.kernel.org, "Theodore Y . Ts'o" , Jaegeuk Kim , Alex Cope , Eric Biggers To: Eric Biggers Return-path: Content-Disposition: inline In-Reply-To: <20170712210035.51534-7-ebiggers3@gmail.com> Sender: linux-crypto-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org On Wed, Jul 12, 2017 at 02:00:35PM -0700, Eric Biggers wrote: > From: Eric Biggers > > 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 Reviewed-by: Michael Halcrow > --- > 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 >