2022-03-04 17:22:00

by Luis Henriques

Subject: [PATCH 3/3] ceph: add support for encrypted snapshot names

Since filenames in encrypted directories are already encrypted and shown
as a base64-encoded string when the directory is locked, snapshot names
should show a similar behaviour.

Signed-off-by: Luís Henriques <[email protected]>
---
fs/ceph/dir.c | 9 +++++++++
fs/ceph/inode.c | 13 +++++++++++++
2 files changed, 22 insertions(+)

diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c
index 934402f5e9e6..17d2f18a1fd1 100644
--- a/fs/ceph/dir.c
+++ b/fs/ceph/dir.c
@@ -1069,6 +1069,15 @@ static int ceph_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
op = CEPH_MDS_OP_MKSNAP;
dout("mksnap dir %p snap '%pd' dn %p\n", dir,
dentry, dentry);
+ /*
+ * Encrypted snapshots require d_revalidate to force a
+ * LOOKUPSNAP to cleanup dcache
+ */
+ if (IS_ENCRYPTED(dir)) {
+ spin_lock(&dentry->d_lock);
+ dentry->d_flags |= DCACHE_NOKEY_NAME;
+ spin_unlock(&dentry->d_lock);
+ }
} else if (ceph_snap(dir) == CEPH_NOSNAP) {
dout("mkdir dir %p dn %p mode 0%ho\n", dir, dentry, mode);
op = CEPH_MDS_OP_MKDIR;
diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index 8b0832271fdf..357335a11384 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -182,6 +182,19 @@ struct inode *ceph_get_snapdir(struct inode *parent)
ci->i_rbytes = 0;
ci->i_btime = ceph_inode(parent)->i_btime;

+ /* if encrypted, just borrow fscrypt_auth from parent */
+ if (IS_ENCRYPTED(parent)) {
+ struct ceph_inode_info *pci = ceph_inode(parent);
+
+ ci->fscrypt_auth = kmemdup(pci->fscrypt_auth,
+ pci->fscrypt_auth_len,
+ GFP_KERNEL);
+ if (ci->fscrypt_auth) {
+ inode->i_flags |= S_ENCRYPTED;
+ ci->fscrypt_auth_len = pci->fscrypt_auth_len;
+ } else
+ dout("Failed to alloc memory for fscrypt_auth in snapdir\n");
+ }
if (inode->i_state & I_NEW) {
inode->i_op = &ceph_snapdir_iops;
inode->i_fop = &ceph_snapdir_fops;

2022-03-04 20:32:43

by Jeff Layton

Subject: Re: [PATCH 3/3] ceph: add support for encrypted snapshot names

On Fri, 2022-03-04 at 16:14 +0000, Lu?s Henriques wrote:
> Since filenames in encrypted directories are already encrypted and shown
> as a base64-encoded string when the directory is locked, snapshot names
> should show a similar behaviour.
>
> Signed-off-by: Lu?s Henriques <[email protected]>
> ---
> fs/ceph/dir.c | 9 +++++++++
> fs/ceph/inode.c | 13 +++++++++++++
> 2 files changed, 22 insertions(+)
>
> diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c
> index 934402f5e9e6..17d2f18a1fd1 100644
> --- a/fs/ceph/dir.c
> +++ b/fs/ceph/dir.c
> @@ -1069,6 +1069,15 @@ static int ceph_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
> op = CEPH_MDS_OP_MKSNAP;
> dout("mksnap dir %p snap '%pd' dn %p\n", dir,
> dentry, dentry);
> + /*
> + * Encrypted snapshots require d_revalidate to force a
> + * LOOKUPSNAP to cleanup dcache
> + */
> + if (IS_ENCRYPTED(dir)) {
> + spin_lock(&dentry->d_lock);
> + dentry->d_flags |= DCACHE_NOKEY_NAME;
> + spin_unlock(&dentry->d_lock);
> + }
> } else if (ceph_snap(dir) == CEPH_NOSNAP) {
> dout("mkdir dir %p dn %p mode 0%ho\n", dir, dentry, mode);
> op = CEPH_MDS_OP_MKDIR;
> diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
> index 8b0832271fdf..357335a11384 100644
> --- a/fs/ceph/inode.c
> +++ b/fs/ceph/inode.c
> @@ -182,6 +182,19 @@ struct inode *ceph_get_snapdir(struct inode *parent)
> ci->i_rbytes = 0;
> ci->i_btime = ceph_inode(parent)->i_btime;
>
> + /* if encrypted, just borrow fscrypt_auth from parent */
> + if (IS_ENCRYPTED(parent)) {
> + struct ceph_inode_info *pci = ceph_inode(parent);
> +
> + ci->fscrypt_auth = kmemdup(pci->fscrypt_auth,
> + pci->fscrypt_auth_len,
> + GFP_KERNEL);
> + if (ci->fscrypt_auth) {
> + inode->i_flags |= S_ENCRYPTED;
> + ci->fscrypt_auth_len = pci->fscrypt_auth_len;
> + } else
> + dout("Failed to alloc memory for fscrypt_auth in snapdir\n");

Should we return an error in this case?

> + }
> if (inode->i_state & I_NEW) {
> inode->i_op = &ceph_snapdir_iops;
> inode->i_fop = &ceph_snapdir_fops;

Seems simple and straightforward at first glance.
--
Jeff Layton <[email protected]>

2022-03-05 14:35:04

by Xiubo Li

Subject: Re: [PATCH 3/3] ceph: add support for encrypted snapshot names

On 3/5/22 12:14 AM, Luís Henriques wrote:
> Since filenames in encrypted directories are already encrypted and shown
> as a base64-encoded string when the directory is locked, snapshot names
> should show a similar behaviour.
>
> Signed-off-by: Luís Henriques <[email protected]>
> ---
> fs/ceph/dir.c | 9 +++++++++
> fs/ceph/inode.c | 13 +++++++++++++
> 2 files changed, 22 insertions(+)
>
> diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c
> index 934402f5e9e6..17d2f18a1fd1 100644
> --- a/fs/ceph/dir.c
> +++ b/fs/ceph/dir.c
> @@ -1069,6 +1069,15 @@ static int ceph_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
> op = CEPH_MDS_OP_MKSNAP;
> dout("mksnap dir %p snap '%pd' dn %p\n", dir,
> dentry, dentry);
> + /*
> + * Encrypted snapshots require d_revalidate to force a
> + * LOOKUPSNAP to cleanup dcache
> + */
> + if (IS_ENCRYPTED(dir)) {
> + spin_lock(&dentry->d_lock);
> + dentry->d_flags |= DCACHE_NOKEY_NAME;
> + spin_unlock(&dentry->d_lock);
> + }

Yeah, this fix looks cool.


> } else if (ceph_snap(dir) == CEPH_NOSNAP) {
> dout("mkdir dir %p dn %p mode 0%ho\n", dir, dentry, mode);
> op = CEPH_MDS_OP_MKDIR;
> diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
> index 8b0832271fdf..357335a11384 100644
> --- a/fs/ceph/inode.c
> +++ b/fs/ceph/inode.c
> @@ -182,6 +182,19 @@ struct inode *ceph_get_snapdir(struct inode *parent)
> ci->i_rbytes = 0;
> ci->i_btime = ceph_inode(parent)->i_btime;
>
> + /* if encrypted, just borrow fscrypt_auth from parent */
> + if (IS_ENCRYPTED(parent)) {
> + struct ceph_inode_info *pci = ceph_inode(parent);
> +
> + ci->fscrypt_auth = kmemdup(pci->fscrypt_auth,
> + pci->fscrypt_auth_len,
> + GFP_KERNEL);
> + if (ci->fscrypt_auth) {
> + inode->i_flags |= S_ENCRYPTED;
> + ci->fscrypt_auth_len = pci->fscrypt_auth_len;
> + } else
> + dout("Failed to alloc memory for fscrypt_auth in snapdir\n");
> + }
> if (inode->i_state & I_NEW) {
> inode->i_op = &ceph_snapdir_iops;
> inode->i_fop = &ceph_snapdir_fops;
>

2022-03-05 15:09:27

by Luis Henriques

Subject: Re: [PATCH 3/3] ceph: add support for encrypted snapshot names

Jeff Layton <[email protected]> writes:

> On Fri, 2022-03-04 at 16:14 +0000, Luís Henriques wrote:
>> Since filenames in encrypted directories are already encrypted and shown
>> as a base64-encoded string when the directory is locked, snapshot names
>> should show a similar behaviour.
>>
>> Signed-off-by: Luís Henriques <[email protected]>
>> ---
>> fs/ceph/dir.c | 9 +++++++++
>> fs/ceph/inode.c | 13 +++++++++++++
>> 2 files changed, 22 insertions(+)
>>
>> diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c
>> index 934402f5e9e6..17d2f18a1fd1 100644
>> --- a/fs/ceph/dir.c
>> +++ b/fs/ceph/dir.c
>> @@ -1069,6 +1069,15 @@ static int ceph_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
>> op = CEPH_MDS_OP_MKSNAP;
>> dout("mksnap dir %p snap '%pd' dn %p\n", dir,
>> dentry, dentry);
>> + /*
>> + * Encrypted snapshots require d_revalidate to force a
>> + * LOOKUPSNAP to cleanup dcache
>> + */
>> + if (IS_ENCRYPTED(dir)) {
>> + spin_lock(&dentry->d_lock);
>> + dentry->d_flags |= DCACHE_NOKEY_NAME;
>> + spin_unlock(&dentry->d_lock);
>> + }
>> } else if (ceph_snap(dir) == CEPH_NOSNAP) {
>> dout("mkdir dir %p dn %p mode 0%ho\n", dir, dentry, mode);
>> op = CEPH_MDS_OP_MKDIR;
>> diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
>> index 8b0832271fdf..357335a11384 100644
>> --- a/fs/ceph/inode.c
>> +++ b/fs/ceph/inode.c
>> @@ -182,6 +182,19 @@ struct inode *ceph_get_snapdir(struct inode *parent)
>> ci->i_rbytes = 0;
>> ci->i_btime = ceph_inode(parent)->i_btime;
>>
>> + /* if encrypted, just borrow fscrypt_auth from parent */
>> + if (IS_ENCRYPTED(parent)) {
>> + struct ceph_inode_info *pci = ceph_inode(parent);
>> +
>> + ci->fscrypt_auth = kmemdup(pci->fscrypt_auth,
>> + pci->fscrypt_auth_len,
>> + GFP_KERNEL);
>> + if (ci->fscrypt_auth) {
>> + inode->i_flags |= S_ENCRYPTED;
>> + ci->fscrypt_auth_len = pci->fscrypt_auth_len;
>> + } else
>> + dout("Failed to alloc memory for fscrypt_auth in snapdir\n");
>
> Should we return an error in this case?

Yeah, definitely. I'll add that and send out v2. Thanks.

Cheers,
--
Luís


>
>> + }
>> if (inode->i_state & I_NEW) {
>> inode->i_op = &ceph_snapdir_iops;
>> inode->i_fop = &ceph_snapdir_fops;
>
> Seems simple and straightforward at first glance.
> --
> Jeff Layton <[email protected]>