eCryptfs: update metadata read/write functions
Update the metadata read/write functions and grow_file() to use the
read_write.c routines. Do not open another lower file; use the persistent
lower file instead. Provide a separate function for
crypto.c::ecryptfs_read_xattr_region() to get to the lower xattr without
having to go through the eCryptfs getxattr.
Signed-off-by: Michael Halcrow <mhalcrow@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/ecryptfs/crypto.c b/fs/ecryptfs/crypto.c
index 7f788ea..55110ff 100644
--- a/fs/ecryptfs/crypto.c
+++ b/fs/ecryptfs/crypto.c
@@ -1342,21 +1342,28 @@
return rc;
}
-int ecryptfs_read_and_validate_header_region(char *data, struct dentry *dentry,
- struct vfsmount *mnt)
+int ecryptfs_read_and_validate_header_region(char *data,
+ struct inode *ecryptfs_inode)
{
+ struct ecryptfs_crypt_stat *crypt_stat =
+ &(ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat);
int rc;
- rc = ecryptfs_read_header_region(data, dentry, mnt);
- if (rc)
+ rc = ecryptfs_read_lower(data, 0, crypt_stat->extent_size,
+ ecryptfs_inode);
+ if (rc) {
+ printk(KERN_ERR "%s: Error reading header region; rc = [%d]\n",
+ __FUNCTION__, rc);
goto out;
- if (!contains_ecryptfs_marker(data + ECRYPTFS_FILE_SIZE_BYTES))
+ }
+ if (!contains_ecryptfs_marker(data + ECRYPTFS_FILE_SIZE_BYTES)) {
rc = -EINVAL;
+ ecryptfs_printk(KERN_DEBUG, "Valid marker not found\n");
+ }
out:
return rc;
}
-
void
ecryptfs_write_header_metadata(char *virt,
struct ecryptfs_crypt_stat *crypt_stat,
@@ -1441,24 +1448,19 @@
static int
ecryptfs_write_metadata_to_contents(struct ecryptfs_crypt_stat *crypt_stat,
- struct file *lower_file, char *page_virt)
+ struct dentry *ecryptfs_dentry,
+ char *page_virt)
{
- mm_segment_t oldfs;
int current_header_page;
int header_pages;
- ssize_t size;
- int rc = 0;
+ int rc;
- lower_file->f_pos = 0;
- oldfs = get_fs();
- set_fs(get_ds());
- size = vfs_write(lower_file, (char __user *)page_virt, PAGE_CACHE_SIZE,
- &lower_file->f_pos);
- if (size < 0) {
- rc = (int)size;
- printk(KERN_ERR "Error attempting to write lower page; "
- "rc = [%d]\n", rc);
- set_fs(oldfs);
+ rc = ecryptfs_write_lower(ecryptfs_dentry->d_inode, page_virt,
+ 0, PAGE_CACHE_SIZE);
+ if (rc) {
+ printk(KERN_ERR "%s: Error attempting to write header "
+ "information to lower file; rc = [%d]\n", __FUNCTION__,
+ rc);
goto out;
}
header_pages = ((crypt_stat->extent_size
@@ -1467,18 +1469,19 @@
memset(page_virt, 0, PAGE_CACHE_SIZE);
current_header_page = 1;
while (current_header_page < header_pages) {
- size = vfs_write(lower_file, (char __user *)page_virt,
- PAGE_CACHE_SIZE, &lower_file->f_pos);
- if (size < 0) {
- rc = (int)size;
- printk(KERN_ERR "Error attempting to write lower page; "
- "rc = [%d]\n", rc);
- set_fs(oldfs);
+ loff_t offset;
+
+ offset = (current_header_page << PAGE_CACHE_SHIFT);
+ if ((rc = ecryptfs_write_lower(ecryptfs_dentry->d_inode,
+ page_virt, offset,
+ PAGE_CACHE_SIZE))) {
+ printk(KERN_ERR "%s: Error attempting to write header "
+ "information to lower file; rc = [%d]\n",
+ __FUNCTION__, rc);
goto out;
}
current_header_page++;
}
- set_fs(oldfs);
out:
return rc;
}
@@ -1498,7 +1501,6 @@
/**
* ecryptfs_write_metadata
* @ecryptfs_dentry: The eCryptfs dentry
- * @lower_file: The lower file struct, which was returned from dentry_open
*
* Write the file headers out. This will likely involve a userspace
* callout, in which the session key is encrypted with one or more
@@ -1506,22 +1508,21 @@
* retrieved via a prompt. Exactly what happens at this point should
* be policy-dependent.
*
+ * TODO: Support header information spanning multiple pages
+ *
* Returns zero on success; non-zero on error
*/
-int ecryptfs_write_metadata(struct dentry *ecryptfs_dentry,
- struct file *lower_file)
+int ecryptfs_write_metadata(struct dentry *ecryptfs_dentry)
{
- struct ecryptfs_crypt_stat *crypt_stat;
+ struct ecryptfs_crypt_stat *crypt_stat =
+ &ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->crypt_stat;
char *page_virt;
- size_t size;
+ size_t size = 0;
int rc = 0;
- crypt_stat = &ecryptfs_inode_to_private(
- ecryptfs_dentry->d_inode)->crypt_stat;
if (likely(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) {
if (!(crypt_stat->flags & ECRYPTFS_KEY_VALID)) {
- ecryptfs_printk(KERN_DEBUG, "Key is "
- "invalid; bailing out\n");
+ printk(KERN_ERR "Key is invalid; bailing out\n");
rc = -EINVAL;
goto out;
}
@@ -1550,7 +1551,8 @@
crypt_stat, page_virt,
size);
else
- rc = ecryptfs_write_metadata_to_contents(crypt_stat, lower_file,
+ rc = ecryptfs_write_metadata_to_contents(crypt_stat,
+ ecryptfs_dentry,
page_virt);
if (rc) {
printk(KERN_ERR "Error writing metadata out to lower file; "
@@ -1678,15 +1680,17 @@
*
* Returns zero on success; non-zero on error
*/
-int ecryptfs_read_xattr_region(char *page_virt, struct dentry *ecryptfs_dentry)
+int ecryptfs_read_xattr_region(char *page_virt, struct inode *ecryptfs_inode)
{
+ struct dentry *lower_dentry =
+ ecryptfs_inode_to_private(ecryptfs_inode)->lower_file->f_dentry;
ssize_t size;
int rc = 0;
- size = ecryptfs_getxattr(ecryptfs_dentry, ECRYPTFS_XATTR_NAME,
- page_virt, ECRYPTFS_DEFAULT_EXTENT_SIZE);
+ size = ecryptfs_getxattr_lower(lower_dentry, ECRYPTFS_XATTR_NAME,
+ page_virt, ECRYPTFS_DEFAULT_EXTENT_SIZE);
if (size < 0) {
- printk(KERN_DEBUG "Error attempting to read the [%s] "
+ printk(KERN_ERR "Error attempting to read the [%s] "
"xattr from the lower file; return value = [%zd]\n",
ECRYPTFS_XATTR_NAME, size);
rc = -EINVAL;
@@ -1701,7 +1705,7 @@
{
int rc;
- rc = ecryptfs_read_xattr_region(page_virt, ecryptfs_dentry);
+ rc = ecryptfs_read_xattr_region(page_virt, ecryptfs_dentry->d_inode);
if (rc)
goto out;
if (!contains_ecryptfs_marker(page_virt + ECRYPTFS_FILE_SIZE_BYTES)) {
@@ -1715,8 +1719,6 @@
/**
* ecryptfs_read_metadata
- * @ecryptfs_dentry: The eCryptfs dentry
- * @lower_file: The lower file from which to read the metadata
*
* Common entry point for reading file metadata. From here, we could
* retrieve the header information from the header region of the file,
@@ -1727,15 +1729,13 @@
*
* Returns zero if valid headers found and parsed; non-zero otherwise
*/
-int ecryptfs_read_metadata(struct dentry *ecryptfs_dentry,
- struct file *lower_file)
+int ecryptfs_read_metadata(struct dentry *ecryptfs_dentry)
{
int rc = 0;
char *page_virt = NULL;
- mm_segment_t oldfs;
- ssize_t bytes_read;
+ struct inode *ecryptfs_inode = ecryptfs_dentry->d_inode;
struct ecryptfs_crypt_stat *crypt_stat =
- &ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->crypt_stat;
+ &ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat;
struct ecryptfs_mount_crypt_stat *mount_crypt_stat =
&ecryptfs_superblock_to_private(
ecryptfs_dentry->d_sb)->mount_crypt_stat;
@@ -1746,27 +1746,18 @@
page_virt = kmem_cache_alloc(ecryptfs_header_cache_1, GFP_USER);
if (!page_virt) {
rc = -ENOMEM;
- ecryptfs_printk(KERN_ERR, "Unable to allocate page_virt\n");
+ printk(KERN_ERR "%s: Unable to allocate page_virt\n",
+ __FUNCTION__);
goto out;
}
- lower_file->f_pos = 0;
- oldfs = get_fs();
- set_fs(get_ds());
- bytes_read = lower_file->f_op->read(lower_file,
- (char __user *)page_virt,
- ECRYPTFS_DEFAULT_EXTENT_SIZE,
- &lower_file->f_pos);
- set_fs(oldfs);
- if (bytes_read != ECRYPTFS_DEFAULT_EXTENT_SIZE) {
- rc = -EINVAL;
- goto out;
- }
- rc = ecryptfs_read_headers_virt(page_virt, crypt_stat,
- ecryptfs_dentry,
- ECRYPTFS_VALIDATE_HEADER_SIZE);
+ rc = ecryptfs_read_lower(page_virt, 0, crypt_stat->extent_size,
+ ecryptfs_inode);
+ if (!rc)
+ rc = ecryptfs_read_headers_virt(page_virt, crypt_stat,
+ ecryptfs_dentry,
+ ECRYPTFS_VALIDATE_HEADER_SIZE);
if (rc) {
- rc = ecryptfs_read_xattr_region(page_virt,
- ecryptfs_dentry);
+ rc = ecryptfs_read_xattr_region(page_virt, ecryptfs_inode);
if (rc) {
printk(KERN_DEBUG "Valid eCryptfs headers not found in "
"file header region or xattr region\n");
