From: Jeff Layton <jlayton@kernel.org>
To: ceph-devel@vger.kernel.org
Cc: xiubli@redhat.com, idryomov@gmail.com, lhenriques@suse.de,
linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
Eric Biggers <ebiggers@google.com>
Subject: [PATCH v12 03/54] fscrypt: export fscrypt_fname_encrypt and fscrypt_fname_encrypted_size
Date: Thu, 31 Mar 2022 11:30:39 -0400 [thread overview]
Message-ID: <20220331153130.41287-4-jlayton@kernel.org> (raw)
In-Reply-To: <20220331153130.41287-1-jlayton@kernel.org>
For ceph, we want to use our own scheme for handling filenames that are
are longer than NAME_MAX after encryption and Base64 encoding. This
allows us to have a consistent view of the encrypted filenames for
clients that don't support fscrypt and clients that do but that don't
have the key.
Currently, fs/crypto only supports encrypting filenames using
fscrypt_setup_filename, but that also handles encoding nokey names. Ceph
can't use that because it handles nokey names in a different way.
Export fscrypt_fname_encrypt. Rename fscrypt_fname_encrypted_size to
__fscrypt_fname_encrypted_size and add a new wrapper called
fscrypt_fname_encrypted_size that takes an inode argument rather than a
pointer to a fscrypt_policy union.
Acked-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
---
fs/crypto/fname.c | 36 ++++++++++++++++++++++++++++++------
fs/crypto/fscrypt_private.h | 9 +++------
fs/crypto/hooks.c | 6 +++---
include/linux/fscrypt.h | 4 ++++
4 files changed, 40 insertions(+), 15 deletions(-)
diff --git a/fs/crypto/fname.c b/fs/crypto/fname.c
index 1e4233c95005..77d38188a168 100644
--- a/fs/crypto/fname.c
+++ b/fs/crypto/fname.c
@@ -79,7 +79,8 @@ static inline bool fscrypt_is_dot_dotdot(const struct qstr *str)
/**
* fscrypt_fname_encrypt() - encrypt a filename
* @inode: inode of the parent directory (for regular filenames)
- * or of the symlink (for symlink targets)
+ * or of the symlink (for symlink targets). Key must already be
+ * set up.
* @iname: the filename to encrypt
* @out: (output) the encrypted filename
* @olen: size of the encrypted filename. It must be at least @iname->len.
@@ -130,6 +131,7 @@ int fscrypt_fname_encrypt(const struct inode *inode, const struct qstr *iname,
return 0;
}
+EXPORT_SYMBOL_GPL(fscrypt_fname_encrypt);
/**
* fname_decrypt() - decrypt a filename
@@ -257,9 +259,9 @@ int fscrypt_base64url_decode(const char *src, int srclen, u8 *dst)
}
EXPORT_SYMBOL_GPL(fscrypt_base64url_decode);
-bool fscrypt_fname_encrypted_size(const union fscrypt_policy *policy,
- u32 orig_len, u32 max_len,
- u32 *encrypted_len_ret)
+bool __fscrypt_fname_encrypted_size(const union fscrypt_policy *policy,
+ u32 orig_len, u32 max_len,
+ u32 *encrypted_len_ret)
{
int padding = 4 << (fscrypt_policy_flags(policy) &
FSCRYPT_POLICY_FLAGS_PAD_MASK);
@@ -273,6 +275,29 @@ bool fscrypt_fname_encrypted_size(const union fscrypt_policy *policy,
return true;
}
+/**
+ * fscrypt_fname_encrypted_size() - calculate length of encrypted filename
+ * @inode: parent inode of dentry name being encrypted. Key must
+ * already be set up.
+ * @orig_len: length of the original filename
+ * @max_len: maximum length to return
+ * @encrypted_len_ret: where calculated length should be returned (on success)
+ *
+ * Filenames that are shorter than the maximum length may have their lengths
+ * increased slightly by encryption, due to padding that is applied.
+ *
+ * Return: false if the orig_len is greater than max_len. Otherwise, true and
+ * fill out encrypted_len_ret with the length (up to max_len).
+ */
+bool fscrypt_fname_encrypted_size(const struct inode *inode, u32 orig_len,
+ u32 max_len, u32 *encrypted_len_ret)
+{
+ return __fscrypt_fname_encrypted_size(&inode->i_crypt_info->ci_policy,
+ orig_len, max_len,
+ encrypted_len_ret);
+}
+EXPORT_SYMBOL_GPL(fscrypt_fname_encrypted_size);
+
/**
* fscrypt_fname_alloc_buffer() - allocate a buffer for presented filenames
* @max_encrypted_len: maximum length of encrypted filenames the buffer will be
@@ -428,8 +453,7 @@ int fscrypt_setup_filename(struct inode *dir, const struct qstr *iname,
return ret;
if (fscrypt_has_encryption_key(dir)) {
- if (!fscrypt_fname_encrypted_size(&dir->i_crypt_info->ci_policy,
- iname->len, NAME_MAX,
+ if (!fscrypt_fname_encrypted_size(dir, iname->len, NAME_MAX,
&fname->crypto_buf.len))
return -ENAMETOOLONG;
fname->crypto_buf.name = kmalloc(fname->crypto_buf.len,
diff --git a/fs/crypto/fscrypt_private.h b/fs/crypto/fscrypt_private.h
index 5b0a9e6478b5..f3e6e566daff 100644
--- a/fs/crypto/fscrypt_private.h
+++ b/fs/crypto/fscrypt_private.h
@@ -297,14 +297,11 @@ void fscrypt_generate_iv(union fscrypt_iv *iv, u64 lblk_num,
const struct fscrypt_info *ci);
/* fname.c */
-int fscrypt_fname_encrypt(const struct inode *inode, const struct qstr *iname,
- u8 *out, unsigned int olen);
-bool fscrypt_fname_encrypted_size(const union fscrypt_policy *policy,
- u32 orig_len, u32 max_len,
- u32 *encrypted_len_ret);
+bool __fscrypt_fname_encrypted_size(const union fscrypt_policy *policy,
+ u32 orig_len, u32 max_len,
+ u32 *encrypted_len_ret);
/* hkdf.c */
-
struct fscrypt_hkdf {
struct crypto_shash *hmac_tfm;
};
diff --git a/fs/crypto/hooks.c b/fs/crypto/hooks.c
index af74599ae1cf..7c01025879b3 100644
--- a/fs/crypto/hooks.c
+++ b/fs/crypto/hooks.c
@@ -228,9 +228,9 @@ int fscrypt_prepare_symlink(struct inode *dir, const char *target,
* counting it (even though it is meaningless for ciphertext) is simpler
* for now since filesystems will assume it is there and subtract it.
*/
- if (!fscrypt_fname_encrypted_size(policy, len,
- max_len - sizeof(struct fscrypt_symlink_data),
- &disk_link->len))
+ if (!__fscrypt_fname_encrypted_size(policy, len,
+ max_len - sizeof(struct fscrypt_symlink_data),
+ &disk_link->len))
return -ENAMETOOLONG;
disk_link->len += sizeof(struct fscrypt_symlink_data);
diff --git a/include/linux/fscrypt.h b/include/linux/fscrypt.h
index 671181d196a8..c90e176b5843 100644
--- a/include/linux/fscrypt.h
+++ b/include/linux/fscrypt.h
@@ -308,8 +308,12 @@ void fscrypt_free_inode(struct inode *inode);
int fscrypt_drop_inode(struct inode *inode);
/* fname.c */
+int fscrypt_fname_encrypt(const struct inode *inode, const struct qstr *iname,
+ u8 *out, unsigned int olen);
int fscrypt_base64url_encode(const u8 *src, int len, char *dst);
int fscrypt_base64url_decode(const char *src, int len, u8 *dst);
+bool fscrypt_fname_encrypted_size(const struct inode *inode, u32 orig_len,
+ u32 max_len, u32 *encrypted_len_ret);
int fscrypt_setup_filename(struct inode *inode, const struct qstr *iname,
int lookup, struct fscrypt_name *fname);
--
2.35.1
next prev parent reply other threads:[~2022-03-31 15:31 UTC|newest]
Thread overview: 63+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-03-31 15:30 [PATCH v12 00/54] ceph+fscrypt: fully-working prototype Jeff Layton
2022-03-31 15:30 ` [PATCH v12 01/54] vfs: export new_inode_pseudo Jeff Layton
2022-03-31 19:50 ` Al Viro
2022-03-31 22:23 ` Jeff Layton
2022-03-31 15:30 ` [PATCH v12 02/54] fscrypt: export fscrypt_base64url_encode and fscrypt_base64url_decode Jeff Layton
2022-03-31 15:30 ` Jeff Layton [this message]
2022-03-31 15:30 ` [PATCH v12 04/54] fscrypt: add fscrypt_context_for_new_inode Jeff Layton
2022-03-31 15:30 ` [PATCH v12 05/54] ceph: preallocate inode for ops that may create one Jeff Layton
2022-03-31 15:30 ` [PATCH v12 06/54] ceph: crypto context handling for ceph Jeff Layton
2022-03-31 15:30 ` [PATCH v12 07/54] ceph: support legacy v1 encryption policy keysetup Jeff Layton
2022-03-31 20:16 ` Eric Biggers
2022-04-01 10:22 ` Luís Henriques
2022-03-31 15:30 ` [PATCH v12 08/54] ceph: add a has_stable_inodes operation for ceph Jeff Layton
2022-03-31 20:03 ` Eric Biggers
2022-04-01 10:37 ` Jeff Layton
2022-04-01 18:16 ` Eric Biggers
2022-04-01 18:51 ` Jeff Layton
2022-03-31 15:30 ` [PATCH v12 09/54] ceph: ensure that we accept a new context from MDS for new inodes Jeff Layton
2022-03-31 15:30 ` [PATCH v12 10/54] ceph: add support for fscrypt_auth/fscrypt_file to cap messages Jeff Layton
2022-03-31 15:30 ` [PATCH v12 11/54] ceph: add ability to set fscrypt_auth via setattr Jeff Layton
2022-03-31 15:30 ` [PATCH v12 12/54] ceph: implement -o test_dummy_encryption mount option Jeff Layton
2022-03-31 15:30 ` [PATCH v12 13/54] ceph: decode alternate_name in lease info Jeff Layton
2022-03-31 15:30 ` [PATCH v12 14/54] ceph: add fscrypt ioctls Jeff Layton
2022-03-31 15:30 ` [PATCH v12 15/54] ceph: make the ioctl cmd more readable in debug log Jeff Layton
2022-03-31 15:30 ` [PATCH v12 16/54] ceph: make ceph_msdc_build_path use ref-walk Jeff Layton
2022-03-31 15:30 ` [PATCH v12 17/54] ceph: add encrypted fname handling to ceph_mdsc_build_path Jeff Layton
2022-03-31 15:30 ` [PATCH v12 18/54] ceph: send altname in MClientRequest Jeff Layton
2022-03-31 15:30 ` [PATCH v12 19/54] ceph: encode encrypted name in dentry release Jeff Layton
2022-03-31 15:30 ` [PATCH v12 20/54] ceph: properly set DCACHE_NOKEY_NAME flag in lookup Jeff Layton
2022-03-31 15:30 ` [PATCH v12 21/54] ceph: set DCACHE_NOKEY_NAME in atomic open Jeff Layton
2022-03-31 15:30 ` [PATCH v12 22/54] ceph: make d_revalidate call fscrypt revalidator for encrypted dentries Jeff Layton
2022-03-31 15:30 ` [PATCH v12 23/54] ceph: add helpers for converting names for userland presentation Jeff Layton
2022-03-31 15:31 ` [PATCH v12 24/54] ceph: fix base64 encoded name's length check in ceph_fname_to_usr() Jeff Layton
2022-03-31 15:31 ` [PATCH v12 25/54] ceph: add fscrypt support to ceph_fill_trace Jeff Layton
2022-03-31 15:31 ` [PATCH v12 26/54] ceph: pass the request to parse_reply_info_readdir() Jeff Layton
2022-03-31 15:31 ` [PATCH v12 27/54] ceph: add ceph_encode_encrypted_dname() helper Jeff Layton
2022-03-31 15:31 ` [PATCH v12 28/54] ceph: add support to readdir for encrypted filenames Jeff Layton
2022-03-31 15:31 ` [PATCH v12 29/54] ceph: create symlinks with encrypted and base64-encoded targets Jeff Layton
2022-03-31 15:31 ` [PATCH v12 30/54] ceph: make ceph_get_name decrypt filenames Jeff Layton
2022-03-31 15:31 ` [PATCH v12 31/54] ceph: add a new ceph.fscrypt.auth vxattr Jeff Layton
2022-03-31 15:31 ` [PATCH v12 32/54] ceph: add some fscrypt guardrails Jeff Layton
2022-03-31 15:31 ` [PATCH v12 33/54] ceph: don't allow changing layout on encrypted files/directories Jeff Layton
2022-03-31 15:31 ` [PATCH v12 34/54] libceph: add CEPH_OSD_OP_ASSERT_VER support Jeff Layton
2022-03-31 15:31 ` [PATCH v12 35/54] ceph: size handling for encrypted inodes in cap updates Jeff Layton
2022-03-31 15:31 ` [PATCH v12 36/54] ceph: fscrypt_file field handling in MClientRequest messages Jeff Layton
2022-03-31 15:31 ` [PATCH v12 37/54] ceph: get file size from fscrypt_file when present in inode traces Jeff Layton
2022-03-31 15:31 ` [PATCH v12 38/54] ceph: handle fscrypt fields in cap messages from MDS Jeff Layton
2022-03-31 15:31 ` [PATCH v12 39/54] ceph: add __ceph_get_caps helper support Jeff Layton
2022-03-31 15:31 ` [PATCH v12 40/54] ceph: add __ceph_sync_read " Jeff Layton
2022-03-31 15:31 ` [PATCH v12 41/54] ceph: add object version support for sync read Jeff Layton
2022-03-31 15:31 ` [PATCH v12 42/54] ceph: add infrastructure for file encryption and decryption Jeff Layton
2022-03-31 15:31 ` [PATCH v12 43/54] ceph: add truncate size handling support for fscrypt Jeff Layton
2022-03-31 15:31 ` [PATCH v12 44/54] libceph: allow ceph_osdc_new_request to accept a multi-op read Jeff Layton
2022-03-31 15:31 ` [PATCH v12 45/54] ceph: disable fallocate for encrypted inodes Jeff Layton
2022-03-31 15:31 ` [PATCH v12 46/54] ceph: disable copy offload on " Jeff Layton
2022-03-31 15:31 ` [PATCH v12 47/54] ceph: don't use special DIO path for " Jeff Layton
2022-03-31 15:31 ` [PATCH v12 48/54] ceph: align data in pages in ceph_sync_write Jeff Layton
2022-03-31 15:31 ` [PATCH v12 49/54] ceph: add read/modify/write to ceph_sync_write Jeff Layton
2022-03-31 15:31 ` [PATCH v12 50/54] ceph: plumb in decryption during sync reads Jeff Layton
2022-03-31 15:31 ` [PATCH v12 51/54] ceph: add fscrypt decryption support to ceph_netfs_issue_op Jeff Layton
2022-03-31 15:31 ` [PATCH v12 52/54] ceph: set i_blkbits to crypto block size for encrypted inodes Jeff Layton
2022-03-31 15:31 ` [PATCH v12 53/54] ceph: add encryption support to writepage Jeff Layton
2022-03-31 15:31 ` [PATCH v12 54/54] ceph: fscrypt support for writepages Jeff Layton
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