Add helper functions for buffer management and for decrypting filenames
returned by the MDS. Wire those into the readdir codepaths.
Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
---
fs/ceph/crypto.c | 76 ++++++++++++++++++++++++++++++++++++++++++++++++
fs/ceph/crypto.h | 41 ++++++++++++++++++++++++++
fs/ceph/dir.c | 62 +++++++++++++++++++++++++++++++--------
fs/ceph/inode.c | 38 ++++++++++++++++++++++--
4 files changed, 202 insertions(+), 15 deletions(-)
diff --git a/fs/ceph/crypto.c b/fs/ceph/crypto.c
index f037a4939026..7ddd434c5baf 100644
--- a/fs/ceph/crypto.c
+++ b/fs/ceph/crypto.c
@@ -107,3 +107,79 @@ int ceph_fscrypt_prepare_context(struct inode *dir, struct inode *inode,
ceph_pagelist_release(pagelist);
return ret;
}
+
+/**
+ * ceph_fname_to_usr - convert a filename for userland presentation
+ * @fname: ceph_fname to be converted
+ * @tname: temporary name buffer to use for conversion (may be NULL)
+ * @oname: where converted name should be placed
+ * @is_nokey: set to true if key wasn't available during conversion (may be NULL)
+ *
+ * Given a filename (usually from the MDS), format it for presentation to
+ * userland. If @parent is not encrypted, just pass it back as-is.
+ *
+ * Otherwise, base64 decode the string, and then ask fscrypt to format it
+ * for userland presentation.
+ *
+ * Returns 0 on success or negative error code on error.
+ */
+int ceph_fname_to_usr(const struct ceph_fname *fname, struct fscrypt_str *tname,
+ struct fscrypt_str *oname, bool *is_nokey)
+{
+ int ret;
+ struct fscrypt_str _tname = FSTR_INIT(NULL, 0);
+ struct fscrypt_str iname;
+
+ if (!IS_ENCRYPTED(fname->dir)) {
+ oname->name = fname->name;
+ oname->len = fname->name_len;
+ return 0;
+ }
+
+ /* Sanity check that the resulting name will fit in the buffer */
+ if (fname->name_len > FSCRYPT_BASE64_CHARS(NAME_MAX))
+ return -EIO;
+
+ ret = __fscrypt_prepare_readdir(fname->dir);
+ if (ret)
+ return ret;
+
+ /*
+ * Use the raw dentry name as sent by the MDS instead of
+ * generating a nokey name via fscrypt.
+ */
+ if (!fscrypt_has_encryption_key(fname->dir)) {
+ oname->name = kmemdup(fname->name, fname->name_len, GFP_KERNEL);
+ oname->len = fname->name_len;
+ if (is_nokey)
+ *is_nokey = true;
+ return 0;
+ }
+
+ if (fname->ctext_len == 0) {
+ int declen;
+
+ if (!tname) {
+ ret = fscrypt_fname_alloc_buffer(NAME_MAX, &_tname);
+ if (ret)
+ return ret;
+ tname = &_tname;
+ }
+
+ declen = fscrypt_base64_decode(fname->name, fname->name_len, tname->name);
+ if (declen <= 0) {
+ ret = -EIO;
+ goto out;
+ }
+ iname.name = tname->name;
+ iname.len = declen;
+ } else {
+ iname.name = fname->ctext;
+ iname.len = fname->ctext_len;
+ }
+
+ ret = fscrypt_fname_disk_to_usr(fname->dir, 0, 0, &iname, oname);
+out:
+ fscrypt_fname_free_buffer(&_tname);
+ return ret;
+}
diff --git a/fs/ceph/crypto.h b/fs/ceph/crypto.h
index 331b9c8da7fb..5a3fb68eb814 100644
--- a/fs/ceph/crypto.h
+++ b/fs/ceph/crypto.h
@@ -11,6 +11,14 @@
#define CEPH_XATTR_NAME_ENCRYPTION_CONTEXT "encryption.ctx"
+struct ceph_fname {
+ struct inode *dir;
+ char *name; // b64 encoded, possibly hashed
+ unsigned char *ctext; // binary crypttext (if any)
+ u32 name_len; // length of name buffer
+ u32 ctext_len; // length of crypttext
+};
+
#ifdef CONFIG_FS_ENCRYPTION
/*
@@ -37,6 +45,22 @@ static inline void ceph_fscrypt_free_dummy_policy(struct ceph_fs_client *fsc)
int ceph_fscrypt_prepare_context(struct inode *dir, struct inode *inode,
struct ceph_acl_sec_ctx *as);
+static inline int ceph_fname_alloc_buffer(struct inode *parent, struct fscrypt_str *fname)
+{
+ if (!IS_ENCRYPTED(parent))
+ return 0;
+ return fscrypt_fname_alloc_buffer(NAME_MAX, fname);
+}
+
+static inline void ceph_fname_free_buffer(struct inode *parent, struct fscrypt_str *fname)
+{
+ if (IS_ENCRYPTED(parent))
+ fscrypt_fname_free_buffer(fname);
+}
+
+int ceph_fname_to_usr(const struct ceph_fname *fname, struct fscrypt_str *tname,
+ struct fscrypt_str *oname, bool *is_nokey);
+
#else /* CONFIG_FS_ENCRYPTION */
static inline void ceph_fscrypt_set_ops(struct super_block *sb)
@@ -55,6 +79,23 @@ static inline int ceph_fscrypt_prepare_context(struct inode *dir, struct inode *
return 0;
}
+static inline int ceph_fname_alloc_buffer(struct inode *parent, struct fscrypt_str *fname)
+{
+ return 0;
+}
+
+static inline void ceph_fname_free_buffer(struct inode *parent, struct fscrypt_str *fname)
+{
+}
+
+static inline int ceph_fname_to_usr(const struct ceph_fname *fname, struct fscrypt_str *tname,
+ struct fscrypt_str *oname, bool *is_nokey)
+{
+ oname->name = fname->name;
+ oname->len = fname->name_len;
+ return 0;
+}
+
#endif /* CONFIG_FS_ENCRYPTION */
#endif
diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c
index 20943769438c..236c381ab6bd 100644
--- a/fs/ceph/dir.c
+++ b/fs/ceph/dir.c
@@ -9,6 +9,7 @@
#include "super.h"
#include "mds_client.h"
+#include "crypto.h"
/*
* Directory operations: readdir, lookup, create, link, unlink,
@@ -241,7 +242,9 @@ static int __dcache_readdir(struct file *file, struct dir_context *ctx,
di = ceph_dentry(dentry);
if (d_unhashed(dentry) ||
d_really_is_negative(dentry) ||
- di->lease_shared_gen != shared_gen) {
+ di->lease_shared_gen != shared_gen ||
+ ((dentry->d_flags & DCACHE_NOKEY_NAME) &&
+ fscrypt_has_encryption_key(dir))) {
spin_unlock(&dentry->d_lock);
dput(dentry);
err = -EAGAIN;
@@ -313,6 +316,8 @@ static int ceph_readdir(struct file *file, struct dir_context *ctx)
int err;
unsigned frag = -1;
struct ceph_mds_reply_info_parsed *rinfo;
+ struct fscrypt_str tname = FSTR_INIT(NULL, 0);
+ struct fscrypt_str oname = FSTR_INIT(NULL, 0);
dout("readdir %p file %p pos %llx\n", inode, file, ctx->pos);
if (dfi->file_info.flags & CEPH_F_ATEND)
@@ -340,6 +345,10 @@ static int ceph_readdir(struct file *file, struct dir_context *ctx)
ctx->pos = 2;
}
+ err = fscrypt_prepare_readdir(inode);
+ if (err)
+ goto out;
+
spin_lock(&ci->i_ceph_lock);
/* request Fx cap. if have Fx, we don't need to release Fs cap
* for later create/unlink. */
@@ -360,6 +369,14 @@ static int ceph_readdir(struct file *file, struct dir_context *ctx)
spin_unlock(&ci->i_ceph_lock);
}
+ err = ceph_fname_alloc_buffer(inode, &tname);
+ if (err < 0)
+ goto out;
+
+ err = ceph_fname_alloc_buffer(inode, &oname);
+ if (err < 0)
+ goto out;
+
/* proceed with a normal readdir */
more:
/* do we have the correct frag content buffered? */
@@ -387,12 +404,14 @@ static int ceph_readdir(struct file *file, struct dir_context *ctx)
dout("readdir fetching %llx.%llx frag %x offset '%s'\n",
ceph_vinop(inode), frag, dfi->last_name);
req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
- if (IS_ERR(req))
- return PTR_ERR(req);
+ if (IS_ERR(req)) {
+ err = PTR_ERR(req);
+ goto out;
+ }
err = ceph_alloc_readdir_reply_buffer(req, inode);
if (err) {
ceph_mdsc_put_request(req);
- return err;
+ goto out;
}
/* hints to request -> mds selection code */
req->r_direct_mode = USE_AUTH_MDS;
@@ -405,7 +424,8 @@ static int ceph_readdir(struct file *file, struct dir_context *ctx)
req->r_path2 = kstrdup(dfi->last_name, GFP_KERNEL);
if (!req->r_path2) {
ceph_mdsc_put_request(req);
- return -ENOMEM;
+ err = -ENOMEM;
+ goto out;
}
} else if (is_hash_order(ctx->pos)) {
req->r_args.readdir.offset_hash =
@@ -426,7 +446,7 @@ static int ceph_readdir(struct file *file, struct dir_context *ctx)
err = ceph_mdsc_do_request(mdsc, NULL, req);
if (err < 0) {
ceph_mdsc_put_request(req);
- return err;
+ goto out;
}
dout("readdir got and parsed readdir result=%d on "
"frag %x, end=%d, complete=%d, hash_order=%d\n",
@@ -479,7 +499,7 @@ static int ceph_readdir(struct file *file, struct dir_context *ctx)
err = note_last_dentry(dfi, rde->name, rde->name_len,
next_offset);
if (err)
- return err;
+ goto out;
} else if (req->r_reply_info.dir_end) {
dfi->next_offset = 2;
/* keep last name */
@@ -507,22 +527,37 @@ static int ceph_readdir(struct file *file, struct dir_context *ctx)
}
for (; i < rinfo->dir_nr; i++) {
struct ceph_mds_reply_dir_entry *rde = rinfo->dir_entries + i;
+ struct ceph_fname fname = { .dir = inode,
+ .name = rde->name,
+ .name_len = rde->name_len,
+ .ctext = rde->altname,
+ .ctext_len = rde->altname_len };
+ u32 olen = oname.len;
BUG_ON(rde->offset < ctx->pos);
+ BUG_ON(!rde->inode.in);
ctx->pos = rde->offset;
dout("readdir (%d/%d) -> %llx '%.*s' %p\n",
i, rinfo->dir_nr, ctx->pos,
rde->name_len, rde->name, &rde->inode.in);
- BUG_ON(!rde->inode.in);
+ err = ceph_fname_to_usr(&fname, &tname, &oname, NULL);
+ if (err) {
+ dout("Unable to decode %.*s. Skipping it.\n", rde->name_len, rde->name);
+ continue;
+ }
- if (!dir_emit(ctx, rde->name, rde->name_len,
+ if (!dir_emit(ctx, oname.name, oname.len,
ceph_present_ino(inode->i_sb, le64_to_cpu(rde->inode.in->ino)),
le32_to_cpu(rde->inode.in->mode) >> 12)) {
dout("filldir stopping us...\n");
- return 0;
+ err = 0;
+ goto out;
}
+
+ /* Reset the lengths to their original allocated vals */
+ oname.len = olen;
ctx->pos++;
}
@@ -577,9 +612,12 @@ static int ceph_readdir(struct file *file, struct dir_context *ctx)
dfi->dir_ordered_count);
spin_unlock(&ci->i_ceph_lock);
}
-
+ err = 0;
dout("readdir %p file %p done.\n", inode, file);
- return 0;
+out:
+ ceph_fname_free_buffer(inode, &tname);
+ ceph_fname_free_buffer(inode, &oname);
+ return err;
}
static void reset_readdir(struct ceph_dir_file_info *dfi)
diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index 2854711e8988..9863a8818132 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -1659,7 +1659,8 @@ int ceph_readdir_prepopulate(struct ceph_mds_request *req,
struct ceph_mds_session *session)
{
struct dentry *parent = req->r_dentry;
- struct ceph_inode_info *ci = ceph_inode(d_inode(parent));
+ struct inode *inode = d_inode(parent);
+ struct ceph_inode_info *ci = ceph_inode(inode);
struct ceph_mds_reply_info_parsed *rinfo = &req->r_reply_info;
struct qstr dname;
struct dentry *dn;
@@ -1669,6 +1670,8 @@ int ceph_readdir_prepopulate(struct ceph_mds_request *req,
u32 last_hash = 0;
u32 fpos_offset;
struct ceph_readdir_cache_control cache_ctl = {};
+ struct fscrypt_str tname = FSTR_INIT(NULL, 0);
+ struct fscrypt_str oname = FSTR_INIT(NULL, 0);
if (test_bit(CEPH_MDS_R_ABORTED, &req->r_req_flags))
return readdir_prepopulate_inodes_only(req, session);
@@ -1720,14 +1723,36 @@ int ceph_readdir_prepopulate(struct ceph_mds_request *req,
cache_ctl.index = req->r_readdir_cache_idx;
fpos_offset = req->r_readdir_offset;
+ err = ceph_fname_alloc_buffer(inode, &tname);
+ if (err < 0)
+ goto out;
+
+ err = ceph_fname_alloc_buffer(inode, &oname);
+ if (err < 0)
+ goto out;
+
/* FIXME: release caps/leases if error occurs */
for (i = 0; i < rinfo->dir_nr; i++) {
+ bool is_nokey = false;
struct ceph_mds_reply_dir_entry *rde = rinfo->dir_entries + i;
struct ceph_vino tvino;
+ u32 olen = oname.len;
+ struct ceph_fname fname = { .dir = inode,
+ .name = rde->name,
+ .name_len = rde->name_len,
+ .ctext = rde->altname,
+ .ctext_len = rde->altname_len };
+
+ err = ceph_fname_to_usr(&fname, &tname, &oname, &is_nokey);
+ if (err) {
+ dout("Unable to decode %.*s. Skipping it.", rde->name_len, rde->name);
+ continue;
+ }
- dname.name = rde->name;
- dname.len = rde->name_len;
+ dname.name = oname.name;
+ dname.len = oname.len;
dname.hash = full_name_hash(parent, dname.name, dname.len);
+ oname.len = olen;
tvino.ino = le64_to_cpu(rde->inode.in->ino);
tvino.snap = le64_to_cpu(rde->inode.in->snapid);
@@ -1758,6 +1783,11 @@ int ceph_readdir_prepopulate(struct ceph_mds_request *req,
err = -ENOMEM;
goto out;
}
+ if (is_nokey) {
+ spin_lock(&dn->d_lock);
+ dn->d_flags |= DCACHE_NOKEY_NAME;
+ spin_unlock(&dn->d_lock);
+ }
} else if (d_really_is_positive(dn) &&
(ceph_ino(d_inode(dn)) != tvino.ino ||
ceph_snap(d_inode(dn)) != tvino.snap)) {
@@ -1848,6 +1878,8 @@ int ceph_readdir_prepopulate(struct ceph_mds_request *req,
req->r_readdir_cache_idx = cache_ctl.index;
}
ceph_readdir_cache_release(&cache_ctl);
+ ceph_fname_free_buffer(inode, &tname);
+ ceph_fname_free_buffer(inode, &oname);
dout("readdir_prepopulate done\n");
return err;
}
--
2.29.2
