forked from luck/tmp_suning_uos_patched
a7550b30ab
This patch removes the most parts of internal crypto codes. And then, it modifies and adds some ext4-specific crypt codes to use the generic facility. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
118 lines
2.8 KiB
C
118 lines
2.8 KiB
C
/*
|
|
* linux/fs/ext4/symlink.c
|
|
*
|
|
* Only fast symlinks left here - the rest is done by generic code. AV, 1999
|
|
*
|
|
* Copyright (C) 1992, 1993, 1994, 1995
|
|
* Remy Card (card@masi.ibp.fr)
|
|
* Laboratoire MASI - Institut Blaise Pascal
|
|
* Universite Pierre et Marie Curie (Paris VI)
|
|
*
|
|
* from
|
|
*
|
|
* linux/fs/minix/symlink.c
|
|
*
|
|
* Copyright (C) 1991, 1992 Linus Torvalds
|
|
*
|
|
* ext4 symlink handling code
|
|
*/
|
|
|
|
#include <linux/fs.h>
|
|
#include <linux/namei.h>
|
|
#include "ext4.h"
|
|
#include "xattr.h"
|
|
|
|
static const char *ext4_encrypted_get_link(struct dentry *dentry,
|
|
struct inode *inode,
|
|
struct delayed_call *done)
|
|
{
|
|
struct page *cpage = NULL;
|
|
char *caddr, *paddr = NULL;
|
|
struct fscrypt_str cstr, pstr;
|
|
struct fscrypt_symlink_data *sd;
|
|
loff_t size = min_t(loff_t, i_size_read(inode), PAGE_SIZE - 1);
|
|
int res;
|
|
u32 max_size = inode->i_sb->s_blocksize;
|
|
|
|
if (!dentry)
|
|
return ERR_PTR(-ECHILD);
|
|
|
|
res = fscrypt_get_encryption_info(inode);
|
|
if (res)
|
|
return ERR_PTR(res);
|
|
|
|
if (ext4_inode_is_fast_symlink(inode)) {
|
|
caddr = (char *) EXT4_I(inode)->i_data;
|
|
max_size = sizeof(EXT4_I(inode)->i_data);
|
|
} else {
|
|
cpage = read_mapping_page(inode->i_mapping, 0, NULL);
|
|
if (IS_ERR(cpage))
|
|
return ERR_CAST(cpage);
|
|
caddr = page_address(cpage);
|
|
caddr[size] = 0;
|
|
}
|
|
|
|
/* Symlink is encrypted */
|
|
sd = (struct fscrypt_symlink_data *)caddr;
|
|
cstr.name = sd->encrypted_path;
|
|
cstr.len = le16_to_cpu(sd->len);
|
|
if ((cstr.len + sizeof(struct fscrypt_symlink_data) - 1) > max_size) {
|
|
/* Symlink data on the disk is corrupted */
|
|
res = -EFSCORRUPTED;
|
|
goto errout;
|
|
}
|
|
|
|
res = fscrypt_fname_alloc_buffer(inode, cstr.len, &pstr);
|
|
if (res)
|
|
goto errout;
|
|
|
|
res = fscrypt_fname_disk_to_usr(inode, 0, 0, &cstr, &pstr);
|
|
if (res < 0)
|
|
goto errout;
|
|
|
|
paddr = pstr.name;
|
|
|
|
/* Null-terminate the name */
|
|
if (res <= pstr.len)
|
|
paddr[res] = '\0';
|
|
if (cpage)
|
|
put_page(cpage);
|
|
set_delayed_call(done, kfree_link, paddr);
|
|
return paddr;
|
|
errout:
|
|
if (cpage)
|
|
put_page(cpage);
|
|
kfree(paddr);
|
|
return ERR_PTR(res);
|
|
}
|
|
|
|
const struct inode_operations ext4_encrypted_symlink_inode_operations = {
|
|
.readlink = generic_readlink,
|
|
.get_link = ext4_encrypted_get_link,
|
|
.setattr = ext4_setattr,
|
|
.setxattr = generic_setxattr,
|
|
.getxattr = generic_getxattr,
|
|
.listxattr = ext4_listxattr,
|
|
.removexattr = generic_removexattr,
|
|
};
|
|
|
|
const struct inode_operations ext4_symlink_inode_operations = {
|
|
.readlink = generic_readlink,
|
|
.get_link = page_get_link,
|
|
.setattr = ext4_setattr,
|
|
.setxattr = generic_setxattr,
|
|
.getxattr = generic_getxattr,
|
|
.listxattr = ext4_listxattr,
|
|
.removexattr = generic_removexattr,
|
|
};
|
|
|
|
const struct inode_operations ext4_fast_symlink_inode_operations = {
|
|
.readlink = generic_readlink,
|
|
.get_link = simple_get_link,
|
|
.setattr = ext4_setattr,
|
|
.setxattr = generic_setxattr,
|
|
.getxattr = generic_getxattr,
|
|
.listxattr = ext4_listxattr,
|
|
.removexattr = generic_removexattr,
|
|
};
|