2022-04-19 16:53:02

by Luis Henriques

[permalink] [raw]
Subject: [PATCH v5 1/5] 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/inode.c | 31 +++++++++++++++++++++++++++----
1 file changed, 27 insertions(+), 4 deletions(-)

diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index fa0d3018d981..8e97efa2b1a7 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -91,9 +91,15 @@ struct inode *ceph_new_inode(struct inode *dir, struct dentry *dentry,
if (err < 0)
goto out_err;

- err = ceph_fscrypt_prepare_context(dir, inode, as_ctx);
- if (err)
- goto out_err;
+ /*
+ * We'll skip setting fscrypt context for snapshots, leaving that for
+ * the handle_reply().
+ */
+ if (ceph_snap(dir) != CEPH_SNAPDIR) {
+ err = ceph_fscrypt_prepare_context(dir, inode, as_ctx);
+ if (err)
+ goto out_err;
+ }

return inode;
out_err:
@@ -157,6 +163,7 @@ struct inode *ceph_get_snapdir(struct inode *parent)
};
struct inode *inode = ceph_get_inode(parent->i_sb, vino, NULL);
struct ceph_inode_info *ci = ceph_inode(inode);
+ int ret = -ENOTDIR;

if (IS_ERR(inode))
return inode;
@@ -182,6 +189,22 @@ 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 snapdir fscrypt_auth\n");
+ ret = -ENOMEM;
+ goto err;
+ }
+ }
if (inode->i_state & I_NEW) {
inode->i_op = &ceph_snapdir_iops;
inode->i_fop = &ceph_snapdir_fops;
@@ -195,7 +218,7 @@ struct inode *ceph_get_snapdir(struct inode *parent)
discard_new_inode(inode);
else
iput(inode);
- return ERR_PTR(-ENOTDIR);
+ return ERR_PTR(ret);
}

const struct inode_operations ceph_file_iops = {