diff --git a/Documentation/filesystems/fscrypt.rst b/Documentation/filesystems/fscrypt.rst
index 776ddc655f7980224d3af3e256e090dedd5240d3..cfbc18f0d9c985a16f6ff9dcd665f6e8d017a067 100644
--- a/Documentation/filesystems/fscrypt.rst
+++ b/Documentation/filesystems/fscrypt.rst
@@ -448,8 +448,14 @@ astute users may notice some differences in behavior:
- The st_size of an encrypted symlink will not necessarily give the
length of the symlink target as required by POSIX. It will actually
- give the length of the ciphertext, which may be slightly longer than
- the plaintext due to the NUL-padding.
+ give the length of the ciphertext, which will be slightly longer
+ than the plaintext due to NUL-padding and an extra 2-byte overhead.
+
+- The maximum length of an encrypted symlink is 2 bytes shorter than
+ the maximum length of an unencrypted symlink. For example, on an
+ EXT4 filesystem with a 4K block size, unencrypted symlinks can be up
+ to 4095 bytes long, while encrypted symlinks can only be up to 4093
+ bytes long (both lengths excluding the terminating null).
Note that mmap *is* supported. This is possible because the pagecache
for an encrypted file contains the plaintext, not the ciphertext.
diff --git a/fs/crypto/crypto.c b/fs/crypto/crypto.c
index 732a786cce9deabe490410ee6dfb15c72fc8f048..ce654526c0fb0d48750be1f2ab306c5be4cc8dd1 100644
--- a/fs/crypto/crypto.c
+++ b/fs/crypto/crypto.c
@@ -27,6 +27,7 @@
#include <linux/dcache.h>
#include <linux/namei.h>
#include <crypto/aes.h>
+#include <crypto/skcipher.h>
#include "fscrypt_private.h"
static unsigned int num_prealloc_crypto_pages = 32;
diff --git a/fs/crypto/fname.c b/fs/crypto/fname.c
index 305541bcd108389695c5c20e37350d76936abb2d..e33f3d3c5ade8ce6e647e6b5021f7e51f00a96c1 100644
--- a/fs/crypto/fname.c
+++ b/fs/crypto/fname.c
@@ -13,42 +13,46 @@
#include <linux/scatterlist.h>
#include <linux/ratelimit.h>
+#include <crypto/skcipher.h>
#include "fscrypt_private.h"
+static inline bool fscrypt_is_dot_dotdot(const struct qstr *str)
+{
+ if (str->len == 1 && str->name[0] == '.')
+ return true;
+
+ if (str->len == 2 && str->name[0] == '.' && str->name[1] == '.')
+ return true;
+
+ return false;
+}
+
/**
* fname_encrypt() - encrypt a filename
*
- * The caller must have allocated sufficient memory for the @oname string.
+ * The output buffer must be at least as large as the input buffer.
+ * Any extra space is filled with NUL padding before encryption.
*
* Return: 0 on success, -errno on failure
*/
-static int fname_encrypt(struct inode *inode,
- const struct qstr *iname, struct fscrypt_str *oname)
+int fname_encrypt(struct inode *inode, const struct qstr *iname,
+ u8 *out, unsigned int olen)
{
struct skcipher_request *req = NULL;
DECLARE_CRYPTO_WAIT(wait);
- struct fscrypt_info *ci = inode->i_crypt_info;
- struct crypto_skcipher *tfm = ci->ci_ctfm;
+ struct crypto_skcipher *tfm = inode->i_crypt_info->ci_ctfm;
int res = 0;
char iv[FS_CRYPTO_BLOCK_SIZE];
struct scatterlist sg;
- int padding = 4 << (ci->ci_flags & FS_POLICY_FLAGS_PAD_MASK);
- unsigned int lim;
- unsigned int cryptlen;
-
- lim = inode->i_sb->s_cop->max_namelen(inode);
- if (iname->len <= 0 || iname->len > lim)
- return -EIO;
/*
* Copy the filename to the output buffer for encrypting in-place and
* pad it with the needed number of NUL bytes.
*/
- cryptlen = max_t(unsigned int, iname->len, FS_CRYPTO_BLOCK_SIZE);
- cryptlen = round_up(cryptlen, padding);
- cryptlen = min(cryptlen, lim);
- memcpy(oname->name, iname->name, iname->len);
- memset(oname->name + iname->len, 0, cryptlen - iname->len);
+ if (WARN_ON(olen < iname->len))
+ return -ENOBUFS;
+ memcpy(out, iname->name, iname->len);
+ memset(out + iname->len, 0, olen - iname->len);
/* Initialize the IV */
memset(iv, 0, FS_CRYPTO_BLOCK_SIZE);
@@ -63,8 +67,8 @@ static int fname_encrypt(struct inode *inode,
skcipher_request_set_callback(req,
CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
crypto_req_done, &wait);
- sg_init_one(&sg, oname->name, cryptlen);
- skcipher_request_set_crypt(req, &sg, &sg, cryptlen, iv);
+ sg_init_one(&sg, out, olen);
+ skcipher_request_set_crypt(req, &sg, &sg, olen, iv);
/* Do the encryption */
res = crypto_wait_req(crypto_skcipher_encrypt(req), &wait);
@@ -75,7 +79,6 @@ static int fname_encrypt(struct inode *inode,
return res;
}
- oname->len = cryptlen;
return 0;
}
@@ -188,50 +191,52 @@ static int digest_decode(const char *src, int len, char *dst)
return cp - dst;
}
-u32 fscrypt_fname_encrypted_size(const struct inode *inode, u32 ilen)
+bool fscrypt_fname_encrypted_size(const struct inode *inode, u32 orig_len,
+ u32 max_len, u32 *encrypted_len_ret)
{
- int padding = 32;
- struct fscrypt_info *ci = inode->i_crypt_info;
-
- if (ci)
- padding = 4 << (ci->ci_flags & FS_POLICY_FLAGS_PAD_MASK);
- ilen = max(ilen, (u32)FS_CRYPTO_BLOCK_SIZE);
- return round_up(ilen, padding);
+ int padding = 4 << (inode->i_crypt_info->ci_flags &
+ FS_POLICY_FLAGS_PAD_MASK);
+ u32 encrypted_len;
+
+ if (orig_len > max_len)
+ return false;
+ encrypted_len = max(orig_len, (u32)FS_CRYPTO_BLOCK_SIZE);
+ encrypted_len = round_up(encrypted_len, padding);
+ *encrypted_len_ret = min(encrypted_len, max_len);
+ return true;
}
-EXPORT_SYMBOL(fscrypt_fname_encrypted_size);
/**
- * fscrypt_fname_crypto_alloc_obuff() -
+ * fscrypt_fname_alloc_buffer - allocate a buffer for presented filenames
+ *
+ * Allocate a buffer that is large enough to hold any decrypted or encoded
+ * filename (null-terminated), for the given maximum encrypted filename length.
*
- * Allocates an output buffer that is sufficient for the crypto operation
- * specified by the context and the direction.
+ * Return: 0 on success, -errno on failure
*/
int fscrypt_fname_alloc_buffer(const struct inode *inode,
- u32 ilen, struct fscrypt_str *crypto_str)
+ u32 max_encrypted_len,
+ struct fscrypt_str *crypto_str)
{
- u32 olen = fscrypt_fname_encrypted_size(inode, ilen);
const u32 max_encoded_len =
max_t(u32, BASE64_CHARS(FSCRYPT_FNAME_MAX_UNDIGESTED_SIZE),
1 + BASE64_CHARS(sizeof(struct fscrypt_digested_name)));
+ u32 max_presented_len;
- crypto_str->len = olen;
- olen = max(olen, max_encoded_len);
+ max_presented_len = max(max_encoded_len, max_encrypted_len);
- /*
- * Allocated buffer can hold one more character to null-terminate the
- * string
- */
- crypto_str->name = kmalloc(olen + 1, GFP_NOFS);
- if (!(crypto_str->name))
+ crypto_str->name = kmalloc(max_presented_len + 1, GFP_NOFS);
+ if (!crypto_str->name)
return -ENOMEM;
+ crypto_str->len = max_presented_len;
return 0;
}
EXPORT_SYMBOL(fscrypt_fname_alloc_buffer);
/**
- * fscrypt_fname_crypto_free_buffer() -
+ * fscrypt_fname_free_buffer - free the buffer for presented filenames
*
- * Frees the buffer allocated for crypto operation.
+ * Free the buffer allocated by fscrypt_fname_alloc_buffer().
*/
void fscrypt_fname_free_buffer(struct fscrypt_str *crypto_str)
{
@@ -297,35 +302,6 @@ int fscrypt_fname_disk_to_usr(struct inode *inode,
}
EXPORT_SYMBOL(fscrypt_fname_disk_to_usr);
-/**
- * fscrypt_fname_usr_to_disk() - converts a filename from user space to disk
- * space
- *
- * The caller must have allocated sufficient memory for the @oname string.
- *
- * Return: 0 on success, -errno on failure
- */
-int fscrypt_fname_usr_to_disk(struct inode *inode,
- const struct qstr *iname,
- struct fscrypt_str *oname)
-{
- if (fscrypt_is_dot_dotdot(iname)) {
- oname->name[0] = '.';
- oname->name[iname->len - 1] = '.';
- oname->len = iname->len;
- return 0;
- }
- if (inode->i_crypt_info)
- return fname_encrypt(inode, iname, oname);
- /*
- * Without a proper key, a user is not allowed to modify the filenames
- * in a directory. Consequently, a user space name cannot be mapped to
- * a disk-space name
- */
- return -ENOKEY;
-}
-EXPORT_SYMBOL(fscrypt_fname_usr_to_disk);
-
/**
* fscrypt_setup_filename() - prepare to search a possibly encrypted directory
* @dir: the directory that will be searched
@@ -369,11 +345,17 @@ int fscrypt_setup_filename(struct inode *dir, const struct qstr *iname,
return ret;
if (dir->i_crypt_info) {
- ret = fscrypt_fname_alloc_buffer(dir, iname->len,
- &fname->crypto_buf);
- if (ret)
- return ret;
- ret = fname_encrypt(dir, iname, &fname->crypto_buf);
+ if (!fscrypt_fname_encrypted_size(dir, iname->len,
+ dir->i_sb->s_cop->max_namelen(dir),
+ &fname->crypto_buf.len))
+ return -ENAMETOOLONG;
+ fname->crypto_buf.name = kmalloc(fname->crypto_buf.len,
+ GFP_NOFS);
+ if (!fname->crypto_buf.name)
+ return -ENOMEM;
+
+ ret = fname_encrypt(dir, iname, fname->crypto_buf.name,
+ fname->crypto_buf.len);
if (ret)
goto errout;
fname->disk_name.name = fname->crypto_buf.name;
@@ -425,7 +407,7 @@ int fscrypt_setup_filename(struct inode *dir, const struct qstr *iname,
return 0;
errout:
- fscrypt_fname_free_buffer(&fname->crypto_buf);
+ kfree(fname->crypto_buf.name);
return ret;
}
EXPORT_SYMBOL(fscrypt_setup_filename);
diff --git a/fs/crypto/fscrypt_private.h b/fs/crypto/fscrypt_private.h
index c0b4f5597e1a3ee772d1c6ecba8f3b73033b74ba..ad6722bae8b7499b8128224cef436898043afc3d 100644
--- a/fs/crypto/fscrypt_private.h
+++ b/fs/crypto/fscrypt_private.h
@@ -50,6 +50,15 @@ struct fscrypt_context {
#define FS_ENCRYPTION_CONTEXT_FORMAT_V1 1
+/**
+ * For encrypted symlinks, the ciphertext length is stored at the beginning
+ * of the string in little-endian format.
+ */
+struct fscrypt_symlink_data {
+ __le16 len;
+ char encrypted_path[1];
+} __packed;
+
/*
* A pointer to this structure is stored in the file system's in-core
* representation of an inode.
@@ -71,7 +80,22 @@ typedef enum {
#define FS_CTX_REQUIRES_FREE_ENCRYPT_FL 0x00000001
#define FS_CTX_HAS_BOUNCE_BUFFER_FL 0x00000002
+static inline bool fscrypt_valid_enc_modes(u32 contents_mode,
+ u32 filenames_mode)
+{
+ if (contents_mode == FS_ENCRYPTION_MODE_AES_128_CBC &&
+ filenames_mode == FS_ENCRYPTION_MODE_AES_128_CTS)
+ return true;
+
+ if (contents_mode == FS_ENCRYPTION_MODE_AES_256_XTS &&
+ filenames_mode == FS_ENCRYPTION_MODE_AES_256_CTS)
+ return true;
+
+ return false;
+}
+
/* crypto.c */
+extern struct kmem_cache *fscrypt_info_cachep;
extern int fscrypt_initialize(unsigned int cop_flags);
extern struct workqueue_struct *fscrypt_read_workqueue;
extern int fscrypt_do_page_crypto(const struct inode *inode,
@@ -83,6 +107,13 @@ extern int fscrypt_do_page_crypto(const struct inode *inode,
extern struct page *fscrypt_alloc_bounce_page(struct fscrypt_ctx *ctx,
gfp_t gfp_flags);
+/* fname.c */
+extern int fname_encrypt(struct inode *inode, const struct qstr *iname,
+ u8 *out, unsigned int olen);
+extern bool fscrypt_fname_encrypted_size(const struct inode *inode,
+ u32 orig_len, u32 max_len,
+ u32 *encrypted_len_ret);
+
/* keyinfo.c */
extern void __exit fscrypt_essiv_cleanup(void);
diff --git a/fs/crypto/hooks.c b/fs/crypto/hooks.c
index 9f5fb2eb9cf7dcd19f47c96295f9a33ac3021192..bec06490fb13be7802cc9c9e830dd7dec27774ab 100644
--- a/fs/crypto/hooks.c
+++ b/fs/crypto/hooks.c
@@ -110,3 +110,161 @@ int __fscrypt_prepare_lookup(struct inode *dir, struct dentry *dentry)
return 0;
}
EXPORT_SYMBOL_GPL(__fscrypt_prepare_lookup);
+
+int __fscrypt_prepare_symlink(struct inode *dir, unsigned int len,
+ unsigned int max_len,
+ struct fscrypt_str *disk_link)
+{
+ int err;
+
+ /*
+ * To calculate the size of the encrypted symlink target we need to know
+ * the amount of NUL padding, which is determined by the flags set in
+ * the encryption policy which will be inherited from the directory.
+ * The easiest way to get access to this is to just load the directory's
+ * fscrypt_info, since we'll need it to create the dir_entry anyway.
+ *
+ * Note: in test_dummy_encryption mode, @dir may be unencrypted.
+ */
+ err = fscrypt_get_encryption_info(dir);
+ if (err)
+ return err;
+ if (!fscrypt_has_encryption_key(dir))
+ return -ENOKEY;
+
+ /*
+ * Calculate the size of the encrypted symlink and verify it won't
+ * exceed max_len. Note that for historical reasons, encrypted symlink
+ * targets are prefixed with the ciphertext length, despite this
+ * actually being redundant with i_size. This decreases by 2 bytes the
+ * longest symlink target we can accept.
+ *
+ * We could recover 1 byte by not counting a null terminator, but
+ * counting it (even though it is meaningless for ciphertext) is simpler
+ * for now since filesystems will assume it is there and subtract it.
+ */
+ if (!fscrypt_fname_encrypted_size(dir, len,
+ max_len - sizeof(struct fscrypt_symlink_data),
+ &disk_link->len))
+ return -ENAMETOOLONG;
+ disk_link->len += sizeof(struct fscrypt_symlink_data);
+
+ disk_link->name = NULL;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(__fscrypt_prepare_symlink);
+
+int __fscrypt_encrypt_symlink(struct inode *inode, const char *target,
+ unsigned int len, struct fscrypt_str *disk_link)
+{
+ int err;
+ struct qstr iname = QSTR_INIT(target, len);
+ struct fscrypt_symlink_data *sd;
+ unsigned int ciphertext_len;
+
+ err = fscrypt_require_key(inode);
+ if (err)
+ return err;
+
+ if (disk_link->name) {
+ /* filesystem-provided buffer */
+ sd = (struct fscrypt_symlink_data *)disk_link->name;
+ } else {
+ sd = kmalloc(disk_link->len, GFP_NOFS);
+ if (!sd)
+ return -ENOMEM;
+ }
+ ciphertext_len = disk_link->len - sizeof(*sd);
+ sd->len = cpu_to_le16(ciphertext_len);
+
+ err = fname_encrypt(inode, &iname, sd->encrypted_path, ciphertext_len);
+ if (err) {
+ if (!disk_link->name)
+ kfree(sd);
+ return err;
+ }
+ /*
+ * Null-terminating the ciphertext doesn't make sense, but we still
+ * count the null terminator in the length, so we might as well
+ * initialize it just in case the filesystem writes it out.
+ */
+ sd->encrypted_path[ciphertext_len] = '\0';
+
+ if (!disk_link->name)
+ disk_link->name = (unsigned char *)sd;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(__fscrypt_encrypt_symlink);
+
+/**
+ * fscrypt_get_symlink - get the target of an encrypted symlink
+ * @inode: the symlink inode
+ * @caddr: the on-disk contents of the symlink
+ * @max_size: size of @caddr buffer
+ * @done: if successful, will be set up to free the returned target
+ *
+ * If the symlink's encryption key is available, we decrypt its target.
+ * Otherwise, we encode its target for presentation.
+ *
+ * This may sleep, so the filesystem must have dropped out of RCU mode already.
+ *
+ * Return: the presentable symlink target or an ERR_PTR()
+ */
+const char *fscrypt_get_symlink(struct inode *inode, const void *caddr,
+ unsigned int max_size,
+ struct delayed_call *done)
+{
+ const struct fscrypt_symlink_data *sd;
+ struct fscrypt_str cstr, pstr;
+ int err;
+
+ /* This is for encrypted symlinks only */
+ if (WARN_ON(!IS_ENCRYPTED(inode)))
+ return ERR_PTR(-EINVAL);
+
+ /*
+ * Try to set up the symlink's encryption key, but we can continue
+ * regardless of whether the key is available or not.
+ */
+ err = fscrypt_get_encryption_info(inode);
+ if (err)
+ return ERR_PTR(err);
+
+ /*
+ * For historical reasons, encrypted symlink targets are prefixed with
+ * the ciphertext length, even though this is redundant with i_size.
+ */
+
+ if (max_size < sizeof(*sd))
+ return ERR_PTR(-EUCLEAN);
+ sd = caddr;
+ cstr.name = (unsigned char *)sd->encrypted_path;
+ cstr.len = le16_to_cpu(sd->len);
+
+ if (cstr.len == 0)
+ return ERR_PTR(-EUCLEAN);
+
+ if (cstr.len + sizeof(*sd) - 1 > max_size)
+ return ERR_PTR(-EUCLEAN);
+
+ err = fscrypt_fname_alloc_buffer(inode, cstr.len, &pstr);
+ if (err)
+ return ERR_PTR(err);
+
+ err = fscrypt_fname_disk_to_usr(inode, 0, 0, &cstr, &pstr);
+ if (err)
+ goto err_kfree;
+
+ err = -EUCLEAN;
+ if (pstr.name[0] == '\0')
+ goto err_kfree;
+
+ pstr.name[pstr.len] = '\0';
+ set_delayed_call(done, kfree_link, pstr.name);
+ return pstr.name;
+
+err_kfree:
+ kfree(pstr.name);
+ return ERR_PTR(err);
+}
+EXPORT_SYMBOL_GPL(fscrypt_get_symlink);
diff --git a/fs/crypto/keyinfo.c b/fs/crypto/keyinfo.c
index 5e6e846f5a24dde322846fe54f642a40fbdc2f3c..05f5ee1f07057ab6484c84c4dc4b66d0f3a1e934 100644
--- a/fs/crypto/keyinfo.c
+++ b/fs/crypto/keyinfo.c
@@ -14,6 +14,7 @@
#include <linux/ratelimit.h>
#include <crypto/aes.h>
#include <crypto/sha.h>
+#include <crypto/skcipher.h>
#include "fscrypt_private.h"
static struct crypto_shash *essiv_hash_tfm;
@@ -354,19 +355,9 @@ int fscrypt_get_encryption_info(struct inode *inode)
}
EXPORT_SYMBOL(fscrypt_get_encryption_info);
-void fscrypt_put_encryption_info(struct inode *inode, struct fscrypt_info *ci)
+void fscrypt_put_encryption_info(struct inode *inode)
{
- struct fscrypt_info *prev;
-
- if (ci == NULL)
- ci = READ_ONCE(inode->i_crypt_info);
- if (ci == NULL)
- return;
-
- prev = cmpxchg(&inode->i_crypt_info, ci, NULL);
- if (prev != ci)
- return;
-
- put_crypt_info(ci);
+ put_crypt_info(inode->i_crypt_info);
+ inode->i_crypt_info = NULL;
}
EXPORT_SYMBOL(fscrypt_put_encryption_info);
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index 9aa1deb1a5256daf58dddf15b9c269b6c0969a9b..b1f21e3a076327df20e5218451ff1feec7e3a13f 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -3057,39 +3057,19 @@ static int ext4_symlink(struct inode *dir,
struct inode *inode;
int err, len = strlen(symname);
int credits;
- bool encryption_required;
struct fscrypt_str disk_link;
- struct fscrypt_symlink_data *sd = NULL;
if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb))))
return -EIO;
- disk_link.len = len + 1;
- disk_link.name = (char *) symname;
-
- encryption_required = (ext4_encrypted_inode(dir) ||
- DUMMY_ENCRYPTION_ENABLED(EXT4_SB(dir->i_sb)));
- if (encryption_required) {
- err = fscrypt_get_encryption_info(dir);
- if (err)
- return err;
- if (!fscrypt_has_encryption_key(dir))
- return -ENOKEY;
- disk_link.len = (fscrypt_fname_encrypted_size(dir, len) +
- sizeof(struct fscrypt_symlink_data));
- sd = kzalloc(disk_link.len, GFP_KERNEL);
- if (!sd)
- return -ENOMEM;
- }
-
- if (disk_link.len > dir->i_sb->s_blocksize) {
- err = -ENAMETOOLONG;
- goto err_free_sd;
- }
+ err = fscrypt_prepare_symlink(dir, symname, len, dir->i_sb->s_blocksize,
+ &disk_link);
+ if (err)
+ return err;
err = dquot_initialize(dir);
if (err)
- goto err_free_sd;
+ return err;
if ((disk_link.len > EXT4_N_BLOCKS * 4)) {
/*
@@ -3118,27 +3098,18 @@ static int ext4_symlink(struct inode *dir,
if (IS_ERR(inode)) {
if (handle)
ext4_journal_stop(handle);
- err = PTR_ERR(inode);
- goto err_free_sd;
+ return PTR_ERR(inode);
}
- if (encryption_required) {
- struct qstr istr;
- struct fscrypt_str ostr =
- FSTR_INIT(sd->encrypted_path, disk_link.len);
-
- istr.name = (const unsigned char *) symname;
- istr.len = len;
- err = fscrypt_fname_usr_to_disk(inode, &istr, &ostr);
+ if (IS_ENCRYPTED(inode)) {
+ err = fscrypt_encrypt_symlink(inode, symname, len, &disk_link);
if (err)
goto err_drop_inode;
- sd->len = cpu_to_le16(ostr.len);
- disk_link.name = (char *) sd;
inode->i_op = &ext4_encrypted_symlink_inode_operations;
}
if ((disk_link.len > EXT4_N_BLOCKS * 4)) {
- if (!encryption_required)
+ if (!IS_ENCRYPTED(inode))
inode->i_op = &ext4_symlink_inode_operations;
inode_nohighmem(inode);
ext4_set_aops(inode);
@@ -3180,7 +3151,7 @@ static int ext4_symlink(struct inode *dir,
} else {
/* clear the extent format for fast symlink */
ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS);
- if (!encryption_required) {
+ if (!IS_ENCRYPTED(inode)) {
inode->i_op = &ext4_fast_symlink_inode_operations;
inode->i_link = (char *)&EXT4_I(inode)->i_data;
}
@@ -3195,16 +3166,17 @@ static int ext4_symlink(struct inode *dir,
if (handle)
ext4_journal_stop(handle);
- kfree(sd);
- return err;
+ goto out_free_encrypted_link;
+
err_drop_inode:
if (handle)
ext4_journal_stop(handle);
clear_nlink(inode);
unlock_new_inode(inode);
iput(inode);
-err_free_sd:
- kfree(sd);
+out_free_encrypted_link:
+ if (disk_link.name != (unsigned char *)symname)
+ kfree(disk_link.name);
return err;
}
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 899e6faf33815ac297ebaa6522ecbd6703464659..421222ec350956ae3e0925d481b0c978b3b37b59 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1073,9 +1073,7 @@ void ext4_clear_inode(struct inode *inode)
jbd2_free_inode(EXT4_I(inode)->jinode);
EXT4_I(inode)->jinode = NULL;
}
-#ifdef CONFIG_EXT4_FS_ENCRYPTION
- fscrypt_put_encryption_info(inode, NULL);
-#endif
+ fscrypt_put_encryption_info(inode);
}
static struct inode *ext4_nfs_get_inode(struct super_block *sb,
diff --git a/fs/ext4/symlink.c b/fs/ext4/symlink.c
index a2006c9af1d968980b0c758ddd3babc8cea5d24f..dd05af983092d6585237e47c440f146a9ab2ee21 100644
--- a/fs/ext4/symlink.c
+++ b/fs/ext4/symlink.c
@@ -28,59 +28,28 @@ static const char *ext4_encrypted_get_link(struct dentry *dentry,
struct delayed_call *done)
{
struct page *cpage = NULL;
- char *caddr, *paddr = NULL;
- struct fscrypt_str cstr, pstr;
- struct fscrypt_symlink_data *sd;
- int res;
- u32 max_size = inode->i_sb->s_blocksize;
+ const void *caddr;
+ unsigned int max_size;
+ const char *paddr;
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;
+ caddr = 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);
+ max_size = inode->i_sb->s_blocksize;
}
- /* 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;
- paddr = pstr.name;
-
- res = fscrypt_fname_disk_to_usr(inode, 0, 0, &cstr, &pstr);
- if (res)
- goto errout;
-
- /* Null-terminate the name */
- paddr[pstr.len] = '\0';
+ paddr = fscrypt_get_symlink(inode, caddr, max_size, done);
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 = {
diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c
index 89c838bfb06789a8c7ba339b1968b5e8adb0bcca..205add3d0f3a0538751cb0281083e52c8ddd4ef2 100644
--- a/fs/f2fs/inode.c
+++ b/fs/f2fs/inode.c
@@ -585,7 +585,7 @@ void f2fs_evict_inode(struct inode *inode)
!exist_written_data(sbi, inode->i_ino, ORPHAN_INO));
}
out_clear:
- fscrypt_put_encryption_info(inode, NULL);
+ fscrypt_put_encryption_info(inode);
clear_inode(inode);
}
diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c
index c4c94c7e9f4fb332a6684d4d46b1efb232d27742..b68e7b03959f5b7cc67d2b6f9b94715d517fac14 100644
--- a/fs/f2fs/namei.c
+++ b/fs/f2fs/namei.c
@@ -486,27 +486,16 @@ static int f2fs_symlink(struct inode *dir, struct dentry *dentry,
struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
struct inode *inode;
size_t len = strlen(symname);
- struct fscrypt_str disk_link = FSTR_INIT((char *)symname, len + 1);
- struct fscrypt_symlink_data *sd = NULL;
+ struct fscrypt_str disk_link;
int err;
if (unlikely(f2fs_cp_error(sbi)))
return -EIO;
- if (f2fs_encrypted_inode(dir)) {
- err = fscrypt_get_encryption_info(dir);
- if (err)
- return err;
-
- if (!fscrypt_has_encryption_key(dir))
- return -ENOKEY;
-
- disk_link.len = (fscrypt_fname_encrypted_size(dir, len) +
- sizeof(struct fscrypt_symlink_data));
- }
-
- if (disk_link.len > dir->i_sb->s_blocksize)
- return -ENAMETOOLONG;
+ err = fscrypt_prepare_symlink(dir, symname, len, dir->i_sb->s_blocksize,
+ &disk_link);
+ if (err)
+ return err;
err = dquot_initialize(dir);
if (err)
@@ -516,7 +505,7 @@ static int f2fs_symlink(struct inode *dir, struct dentry *dentry,
if (IS_ERR(inode))
return PTR_ERR(inode);
- if (f2fs_encrypted_inode(inode))
+ if (IS_ENCRYPTED(inode))
inode->i_op = &f2fs_encrypted_symlink_inode_operations;
else
inode->i_op = &f2fs_symlink_inode_operations;
@@ -526,38 +515,13 @@ static int f2fs_symlink(struct inode *dir, struct dentry *dentry,
f2fs_lock_op(sbi);
err = f2fs_add_link(dentry, inode);
if (err)
- goto out;
+ goto out_handle_failed_inode;
f2fs_unlock_op(sbi);
alloc_nid_done(sbi, inode->i_ino);
- if (f2fs_encrypted_inode(inode)) {
- struct qstr istr = QSTR_INIT(symname, len);
- struct fscrypt_str ostr;
-
- sd = f2fs_kzalloc(sbi, disk_link.len, GFP_NOFS);
- if (!sd) {
- err = -ENOMEM;
- goto err_out;
- }
-
- err = fscrypt_get_encryption_info(inode);
- if (err)
- goto err_out;
-
- if (!fscrypt_has_encryption_key(inode)) {
- err = -ENOKEY;
- goto err_out;
- }
-
- ostr.name = sd->encrypted_path;
- ostr.len = disk_link.len;
- err = fscrypt_fname_usr_to_disk(inode, &istr, &ostr);
- if (err)
- goto err_out;
-
- sd->len = cpu_to_le16(ostr.len);
- disk_link.name = (char *)sd;
- }
+ err = fscrypt_encrypt_symlink(inode, symname, len, &disk_link);
+ if (err)
+ goto err_out;
err = page_symlink(inode, disk_link.name, disk_link.len);
@@ -584,12 +548,14 @@ static int f2fs_symlink(struct inode *dir, struct dentry *dentry,
f2fs_unlink(dir, dentry);
}
- kfree(sd);
-
f2fs_balance_fs(sbi, true);
- return err;
-out:
+ goto out_free_encrypted_link;
+
+out_handle_failed_inode:
handle_failed_inode(inode);
+out_free_encrypted_link:
+ if (disk_link.name != (unsigned char *)symname)
+ kfree(disk_link.name);
return err;
}
@@ -1148,68 +1114,20 @@ static const char *f2fs_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 = FSTR_INIT(NULL, 0);
- struct fscrypt_str pstr = FSTR_INIT(NULL, 0);
- struct fscrypt_symlink_data *sd;
- u32 max_size = inode->i_sb->s_blocksize;
- int res;
+ struct page *page;
+ const char *target;
if (!dentry)
return ERR_PTR(-ECHILD);
- res = fscrypt_get_encryption_info(inode);
- if (res)
- return ERR_PTR(res);
-
- cpage = read_mapping_page(inode->i_mapping, 0, NULL);
- if (IS_ERR(cpage))
- return ERR_CAST(cpage);
- caddr = page_address(cpage);
-
- /* Symlink is encrypted */
- sd = (struct fscrypt_symlink_data *)caddr;
- cstr.name = sd->encrypted_path;
- cstr.len = le16_to_cpu(sd->len);
-
- /* this is broken symlink case */
- if (unlikely(cstr.len == 0)) {
- res = -ENOENT;
- goto errout;
- }
-
- if ((cstr.len + sizeof(struct fscrypt_symlink_data) - 1) > max_size) {
- /* Symlink data on the disk is corrupted */
- res = -EIO;
- 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)
- goto errout;
-
- /* this is broken symlink case */
- if (unlikely(pstr.name[0] == 0)) {
- res = -ENOENT;
- goto errout;
- }
-
- paddr = pstr.name;
-
- /* Null-terminate the name */
- paddr[pstr.len] = '\0';
+ page = read_mapping_page(inode->i_mapping, 0, NULL);
+ if (IS_ERR(page))
+ return ERR_CAST(page);
- put_page(cpage);
- set_delayed_call(done, kfree_link, paddr);
- return paddr;
-errout:
- fscrypt_fname_free_buffer(&pstr);
- put_page(cpage);
- return ERR_PTR(res);
+ target = fscrypt_get_symlink(inode, page_address(page),
+ inode->i_sb->s_blocksize, done);
+ put_page(page);
+ return target;
}
const struct inode_operations f2fs_encrypted_symlink_inode_operations = {
diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c
index a2ea4856e67b127e97b56d505f2b694df1f57d1a..9d7fb88e172e3d2f17acff5a72f432a8d3e5bddd 100644
--- a/fs/ubifs/dir.c
+++ b/fs/ubifs/dir.c
@@ -1138,38 +1138,24 @@ static int ubifs_symlink(struct inode *dir, struct dentry *dentry,
struct ubifs_info *c = dir->i_sb->s_fs_info;
int err, len = strlen(symname);
int sz_change = CALC_DENT_SIZE(len);
- struct fscrypt_str disk_link = FSTR_INIT((char *)symname, len + 1);
- struct fscrypt_symlink_data *sd = NULL;
+ struct fscrypt_str disk_link;
struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
.new_ino_d = ALIGN(len, 8),
.dirtied_ino = 1 };
struct fscrypt_name nm;
- if (ubifs_crypt_is_encrypted(dir)) {
- err = fscrypt_get_encryption_info(dir);
- if (err)
- goto out_budg;
-
- if (!fscrypt_has_encryption_key(dir)) {
- err = -EPERM;
- goto out_budg;
- }
+ dbg_gen("dent '%pd', target '%s' in dir ino %lu", dentry,
+ symname, dir->i_ino);
- disk_link.len = (fscrypt_fname_encrypted_size(dir, len) +
- sizeof(struct fscrypt_symlink_data));
- }
+ err = fscrypt_prepare_symlink(dir, symname, len, UBIFS_MAX_INO_DATA,
+ &disk_link);
+ if (err)
+ return err;
/*
* Budget request settings: new inode, new direntry and changing parent
* directory inode.
*/
-
- dbg_gen("dent '%pd', target '%s' in dir ino %lu", dentry,
- symname, dir->i_ino);
-
- if (disk_link.len > UBIFS_MAX_INO_DATA)
- return -ENAMETOOLONG;
-
err = ubifs_budget_space(c, &req);
if (err)
return err;
@@ -1191,38 +1177,20 @@ static int ubifs_symlink(struct inode *dir, struct dentry *dentry,
goto out_inode;
}
- if (ubifs_crypt_is_encrypted(dir)) {
- struct qstr istr = QSTR_INIT(symname, len);
- struct fscrypt_str ostr;
-
- sd = kzalloc(disk_link.len, GFP_NOFS);
- if (!sd) {
- err = -ENOMEM;
- goto out_inode;
- }
-
- ostr.name = sd->encrypted_path;
- ostr.len = disk_link.len;
-
- err = fscrypt_fname_usr_to_disk(inode, &istr, &ostr);
- if (err) {
- kfree(sd);
+ if (IS_ENCRYPTED(inode)) {
+ disk_link.name = ui->data; /* encrypt directly into ui->data */
+ err = fscrypt_encrypt_symlink(inode, symname, len, &disk_link);
+ if (err)
goto out_inode;
- }
-
- sd->len = cpu_to_le16(ostr.len);
- disk_link.name = (char *)sd;
} else {
+ memcpy(ui->data, disk_link.name, disk_link.len);
inode->i_link = ui->data;
}
- memcpy(ui->data, disk_link.name, disk_link.len);
- ((char *)ui->data)[disk_link.len - 1] = '\0';
-
/*
* The terminating zero byte is not written to the flash media and it
* is put just to make later in-memory string processing simpler. Thus,
- * data length is @len, not @len + %1.
+ * data length is @disk_link.len - 1, not @disk_link.len.
*/
ui->data_len = disk_link.len - 1;
inode->i_size = ubifs_inode(inode)->ui_size = disk_link.len - 1;
@@ -1240,11 +1208,10 @@ static int ubifs_symlink(struct inode *dir, struct dentry *dentry,
goto out_cancel;
mutex_unlock(&dir_ui->ui_mutex);
- ubifs_release_budget(c, &req);
insert_inode_hash(inode);
d_instantiate(dentry, inode);
- fscrypt_free_filename(&nm);
- return 0;
+ err = 0;
+ goto out_fname;
out_cancel:
dir->i_size -= sz_change;
diff --git a/fs/ubifs/file.c b/fs/ubifs/file.c
index 9fe194a4fa9ba5a80aa36ff3b37fa4ec78452544..cf348ba9923858927d6f19a92b65985184285dc3 100644
--- a/fs/ubifs/file.c
+++ b/fs/ubifs/file.c
@@ -1629,49 +1629,17 @@ static const char *ubifs_get_link(struct dentry *dentry,
struct inode *inode,
struct delayed_call *done)
{
- int err;
- struct fscrypt_symlink_data *sd;
struct ubifs_inode *ui = ubifs_inode(inode);
- struct fscrypt_str cstr;
- struct fscrypt_str pstr;
- if (!ubifs_crypt_is_encrypted(inode))
+ if (!IS_ENCRYPTED(inode))
return ui->data;
if (!dentry)
return ERR_PTR(-ECHILD);
- err = fscrypt_get_encryption_info(inode);
- if (err)
- return ERR_PTR(err);
-
- sd = (struct fscrypt_symlink_data *)ui->data;
- cstr.name = sd->encrypted_path;
- cstr.len = le16_to_cpu(sd->len);
-
- if (cstr.len == 0)
- return ERR_PTR(-ENOENT);
-
- if ((cstr.len + sizeof(struct fscrypt_symlink_data) - 1) > ui->data_len)
- return ERR_PTR(-EIO);
-
- err = fscrypt_fname_alloc_buffer(inode, cstr.len, &pstr);
- if (err)
- return ERR_PTR(err);
-
- err = fscrypt_fname_disk_to_usr(inode, 0, 0, &cstr, &pstr);
- if (err) {
- fscrypt_fname_free_buffer(&pstr);
- return ERR_PTR(err);
- }
-
- pstr.name[pstr.len] = '\0';
-
- set_delayed_call(done, kfree_link, pstr.name);
- return pstr.name;
+ return fscrypt_get_symlink(inode, ui->data, ui->data_len, done);
}
-
const struct address_space_operations ubifs_file_address_operations = {
.readpage = ubifs_readpage,
.writepage = ubifs_writepage,
diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index 0beb285b143da6cfe9cc238ede64313f8f75a604..b16ef162344ab382143578d277248c88f2fdc067 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -379,9 +379,7 @@ static void ubifs_evict_inode(struct inode *inode)
}
done:
clear_inode(inode);
-#ifdef CONFIG_UBIFS_FS_ENCRYPTION
- fscrypt_put_encryption_info(inode, NULL);
-#endif
+ fscrypt_put_encryption_info(inode);
}
static void ubifs_dirty_inode(struct inode *inode, int flags)
diff --git a/include/linux/fscrypt.h b/include/linux/fscrypt.h
index 08b4b40c5aa83ac265f0d5dadbb06cde79641323..952ab97af325ea32b537cf32f32a2afd30648cdd 100644
--- a/include/linux/fscrypt.h
+++ b/include/linux/fscrypt.h
@@ -14,42 +14,13 @@
#ifndef _LINUX_FSCRYPT_H
#define _LINUX_FSCRYPT_H
-#include <linux/key.h>
#include <linux/fs.h>
-#include <linux/mm.h>
-#include <linux/bio.h>
-#include <linux/dcache.h>
-#include <crypto/skcipher.h>
-#include <uapi/linux/fs.h>
#define FS_CRYPTO_BLOCK_SIZE 16
+struct fscrypt_ctx;
struct fscrypt_info;
-struct fscrypt_ctx {
- union {
- struct {
- struct page *bounce_page; /* Ciphertext page */
- struct page *control_page; /* Original page */
- } w;
- struct {
- struct bio *bio;
- struct work_struct work;
- } r;
- struct list_head free_list; /* Free list */
- };
- u8 flags; /* Flags */
-};
-
-/**
- * For encrypted symlinks, the ciphertext length is stored at the beginning
- * of the string in little-endian format.
- */
-struct fscrypt_symlink_data {
- __le16 len;
- char encrypted_path[1];
-} __packed;
-
struct fscrypt_str {
unsigned char *name;
u32 len;
@@ -68,89 +39,14 @@ struct fscrypt_name {
#define fname_name(p) ((p)->disk_name.name)
#define fname_len(p) ((p)->disk_name.len)
-/*
- * fscrypt superblock flags
- */
-#define FS_CFLG_OWN_PAGES (1U << 1)
-
-/*
- * crypto opertions for filesystems
- */
-struct fscrypt_operations {
- unsigned int flags;
- const char *key_prefix;
- int (*get_context)(struct inode *, void *, size_t);
- int (*set_context)(struct inode *, const void *, size_t, void *);
- bool (*dummy_context)(struct inode *);
- bool (*empty_dir)(struct inode *);
- unsigned (*max_namelen)(struct inode *);
-};
-
/* Maximum value for the third parameter of fscrypt_operations.set_context(). */
#define FSCRYPT_SET_CONTEXT_MAX_SIZE 28
-static inline bool fscrypt_dummy_context_enabled(struct inode *inode)
-{
- if (inode->i_sb->s_cop->dummy_context &&
- inode->i_sb->s_cop->dummy_context(inode))
- return true;
- return false;
-}
-
-static inline bool fscrypt_valid_enc_modes(u32 contents_mode,
- u32 filenames_mode)
-{
- if (contents_mode == FS_ENCRYPTION_MODE_AES_128_CBC &&
- filenames_mode == FS_ENCRYPTION_MODE_AES_128_CTS)
- return true;
-
- if (contents_mode == FS_ENCRYPTION_MODE_AES_256_XTS &&
- filenames_mode == FS_ENCRYPTION_MODE_AES_256_CTS)
- return true;
-
- return false;
-}
-
-static inline bool fscrypt_is_dot_dotdot(const struct qstr *str)
-{
- if (str->len == 1 && str->name[0] == '.')
- return true;
-
- if (str->len == 2 && str->name[0] == '.' && str->name[1] == '.')
- return true;
-
- return false;
-}
-
#if __FS_HAS_ENCRYPTION
-
-static inline struct page *fscrypt_control_page(struct page *page)
-{
- return ((struct fscrypt_ctx *)page_private(page))->w.control_page;
-}
-
-static inline bool fscrypt_has_encryption_key(const struct inode *inode)
-{
- return (inode->i_crypt_info != NULL);
-}
-
#include <linux/fscrypt_supp.h>
-
-#else /* !__FS_HAS_ENCRYPTION */
-
-static inline struct page *fscrypt_control_page(struct page *page)
-{
- WARN_ON_ONCE(1);
- return ERR_PTR(-EINVAL);
-}
-
-static inline bool fscrypt_has_encryption_key(const struct inode *inode)
-{
- return 0;
-}
-
+#else
#include <linux/fscrypt_notsupp.h>
-#endif /* __FS_HAS_ENCRYPTION */
+#endif
/**
* fscrypt_require_key - require an inode's encryption key
@@ -291,4 +187,68 @@ static inline int fscrypt_prepare_setattr(struct dentry *dentry,
return 0;
}
+/**
+ * fscrypt_prepare_symlink - prepare to create a possibly-encrypted symlink
+ * @dir: directory in which the symlink is being created
+ * @target: plaintext symlink target
+ * @len: length of @target excluding null terminator
+ * @max_len: space the filesystem has available to store the symlink target
+ * @disk_link: (out) the on-disk symlink target being prepared
+ *
+ * This function computes the size the symlink target will require on-disk,
+ * stores it in @disk_link->len, and validates it against @max_len. An
+ * encrypted symlink may be longer than the original.
+ *
+ * Additionally, @disk_link->name is set to @target if the symlink will be
+ * unencrypted, but left NULL if the symlink will be encrypted. For encrypted
+ * symlinks, the filesystem must call fscrypt_encrypt_symlink() to create the
+ * on-disk target later. (The reason for the two-step process is that some
+ * filesystems need to know the size of the symlink target before creating the
+ * inode, e.g. to determine whether it will be a "fast" or "slow" symlink.)
+ *
+ * Return: 0 on success, -ENAMETOOLONG if the symlink target is too long,
+ * -ENOKEY if the encryption key is missing, or another -errno code if a problem
+ * occurred while setting up the encryption key.
+ */
+static inline int fscrypt_prepare_symlink(struct inode *dir,
+ const char *target,
+ unsigned int len,
+ unsigned int max_len,
+ struct fscrypt_str *disk_link)
+{
+ if (IS_ENCRYPTED(dir) || fscrypt_dummy_context_enabled(dir))
+ return __fscrypt_prepare_symlink(dir, len, max_len, disk_link);
+
+ disk_link->name = (unsigned char *)target;
+ disk_link->len = len + 1;
+ if (disk_link->len > max_len)
+ return -ENAMETOOLONG;
+ return 0;
+}
+
+/**
+ * fscrypt_encrypt_symlink - encrypt the symlink target if needed
+ * @inode: symlink inode
+ * @target: plaintext symlink target
+ * @len: length of @target excluding null terminator
+ * @disk_link: (in/out) the on-disk symlink target being prepared
+ *
+ * If the symlink target needs to be encrypted, then this function encrypts it
+ * into @disk_link->name. fscrypt_prepare_symlink() must have been called
+ * previously to compute @disk_link->len. If the filesystem did not allocate a
+ * buffer for @disk_link->name after calling fscrypt_prepare_link(), then one
+ * will be kmalloc()'ed and the filesystem will be responsible for freeing it.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static inline int fscrypt_encrypt_symlink(struct inode *inode,
+ const char *target,
+ unsigned int len,
+ struct fscrypt_str *disk_link)
+{
+ if (IS_ENCRYPTED(inode))
+ return __fscrypt_encrypt_symlink(inode, target, len, disk_link);
+ return 0;
+}
+
#endif /* _LINUX_FSCRYPT_H */
diff --git a/include/linux/fscrypt_notsupp.h b/include/linux/fscrypt_notsupp.h
index 63e58808519aaeb60aea66287b40963668a8c6bc..44b50c04bae9a3ad31cb319635c683dfa1899c6b 100644
--- a/include/linux/fscrypt_notsupp.h
+++ b/include/linux/fscrypt_notsupp.h
@@ -14,6 +14,16 @@
#ifndef _LINUX_FSCRYPT_NOTSUPP_H
#define _LINUX_FSCRYPT_NOTSUPP_H
+static inline bool fscrypt_has_encryption_key(const struct inode *inode)
+{
+ return false;
+}
+
+static inline bool fscrypt_dummy_context_enabled(struct inode *inode)
+{
+ return false;
+}
+
/* crypto.c */
static inline struct fscrypt_ctx *fscrypt_get_ctx(const struct inode *inode,
gfp_t gfp_flags)
@@ -43,6 +53,11 @@ static inline int fscrypt_decrypt_page(const struct inode *inode,
return -EOPNOTSUPP;
}
+static inline struct page *fscrypt_control_page(struct page *page)
+{
+ WARN_ON_ONCE(1);
+ return ERR_PTR(-EINVAL);
+}
static inline void fscrypt_restore_control_page(struct page *page)
{
@@ -90,8 +105,7 @@ static inline int fscrypt_get_encryption_info(struct inode *inode)
return -EOPNOTSUPP;
}
-static inline void fscrypt_put_encryption_info(struct inode *inode,
- struct fscrypt_info *ci)
+static inline void fscrypt_put_encryption_info(struct inode *inode)
{
return;
}
@@ -116,16 +130,8 @@ static inline void fscrypt_free_filename(struct fscrypt_name *fname)
return;
}
-static inline u32 fscrypt_fname_encrypted_size(const struct inode *inode,
- u32 ilen)
-{
- /* never happens */
- WARN_ON(1);
- return 0;
-}
-
static inline int fscrypt_fname_alloc_buffer(const struct inode *inode,
- u32 ilen,
+ u32 max_encrypted_len,
struct fscrypt_str *crypto_str)
{
return -EOPNOTSUPP;
@@ -144,13 +150,6 @@ static inline int fscrypt_fname_disk_to_usr(struct inode *inode,
return -EOPNOTSUPP;
}
-static inline int fscrypt_fname_usr_to_disk(struct inode *inode,
- const struct qstr *iname,
- struct fscrypt_str *oname)
-{
- return -EOPNOTSUPP;
-}
-
static inline bool fscrypt_match_name(const struct fscrypt_name *fname,
const u8 *de_name, u32 de_name_len)
{
@@ -208,4 +207,28 @@ static inline int __fscrypt_prepare_lookup(struct inode *dir,
return -EOPNOTSUPP;
}
+static inline int __fscrypt_prepare_symlink(struct inode *dir,
+ unsigned int len,
+ unsigned int max_len,
+ struct fscrypt_str *disk_link)
+{
+ return -EOPNOTSUPP;
+}
+
+static inline int __fscrypt_encrypt_symlink(struct inode *inode,
+ const char *target,
+ unsigned int len,
+ struct fscrypt_str *disk_link)
+{
+ return -EOPNOTSUPP;
+}
+
+static inline const char *fscrypt_get_symlink(struct inode *inode,
+ const void *caddr,
+ unsigned int max_size,
+ struct delayed_call *done)
+{
+ return ERR_PTR(-EOPNOTSUPP);
+}
+
#endif /* _LINUX_FSCRYPT_NOTSUPP_H */
diff --git a/include/linux/fscrypt_supp.h b/include/linux/fscrypt_supp.h
index cf9e9fc02f0afe7348404ca769927d587a63ec64..477a7a6504d214aa80b994106943d7ef6878ee34 100644
--- a/include/linux/fscrypt_supp.h
+++ b/include/linux/fscrypt_supp.h
@@ -11,8 +11,54 @@
#ifndef _LINUX_FSCRYPT_SUPP_H
#define _LINUX_FSCRYPT_SUPP_H
+#include <linux/mm.h>
+#include <linux/slab.h>
+
+/*
+ * fscrypt superblock flags
+ */
+#define FS_CFLG_OWN_PAGES (1U << 1)
+
+/*
+ * crypto operations for filesystems
+ */
+struct fscrypt_operations {
+ unsigned int flags;
+ const char *key_prefix;
+ int (*get_context)(struct inode *, void *, size_t);
+ int (*set_context)(struct inode *, const void *, size_t, void *);
+ bool (*dummy_context)(struct inode *);
+ bool (*empty_dir)(struct inode *);
+ unsigned (*max_namelen)(struct inode *);
+};
+
+struct fscrypt_ctx {
+ union {
+ struct {
+ struct page *bounce_page; /* Ciphertext page */
+ struct page *control_page; /* Original page */
+ } w;
+ struct {
+ struct bio *bio;
+ struct work_struct work;
+ } r;
+ struct list_head free_list; /* Free list */
+ };
+ u8 flags; /* Flags */
+};
+
+static inline bool fscrypt_has_encryption_key(const struct inode *inode)
+{
+ return (inode->i_crypt_info != NULL);
+}
+
+static inline bool fscrypt_dummy_context_enabled(struct inode *inode)
+{
+ return inode->i_sb->s_cop->dummy_context &&
+ inode->i_sb->s_cop->dummy_context(inode);
+}
+
/* crypto.c */
-extern struct kmem_cache *fscrypt_info_cachep;
extern struct fscrypt_ctx *fscrypt_get_ctx(const struct inode *, gfp_t);
extern void fscrypt_release_ctx(struct fscrypt_ctx *);
extern struct page *fscrypt_encrypt_page(const struct inode *, struct page *,
@@ -20,6 +66,12 @@ extern struct page *fscrypt_encrypt_page(const struct inode *, struct page *,
u64, gfp_t);
extern int fscrypt_decrypt_page(const struct inode *, struct page *, unsigned int,
unsigned int, u64);
+
+static inline struct page *fscrypt_control_page(struct page *page)
+{
+ return ((struct fscrypt_ctx *)page_private(page))->w.control_page;
+}
+
extern void fscrypt_restore_control_page(struct page *);
extern const struct dentry_operations fscrypt_d_ops;
@@ -44,7 +96,7 @@ extern int fscrypt_inherit_context(struct inode *, struct inode *,
void *, bool);
/* keyinfo.c */
extern int fscrypt_get_encryption_info(struct inode *);
-extern void fscrypt_put_encryption_info(struct inode *, struct fscrypt_info *);
+extern void fscrypt_put_encryption_info(struct inode *);
/* fname.c */
extern int fscrypt_setup_filename(struct inode *, const struct qstr *,
@@ -55,14 +107,11 @@ static inline void fscrypt_free_filename(struct fscrypt_name *fname)
kfree(fname->crypto_buf.name);
}
-extern u32 fscrypt_fname_encrypted_size(const struct inode *, u32);
extern int fscrypt_fname_alloc_buffer(const struct inode *, u32,
struct fscrypt_str *);
extern void fscrypt_fname_free_buffer(struct fscrypt_str *);
extern int fscrypt_fname_disk_to_usr(struct inode *, u32, u32,
const struct fscrypt_str *, struct fscrypt_str *);
-extern int fscrypt_fname_usr_to_disk(struct inode *, const struct qstr *,
- struct fscrypt_str *);
#define FSCRYPT_FNAME_MAX_UNDIGESTED_SIZE 32
@@ -153,5 +202,14 @@ extern int __fscrypt_prepare_rename(struct inode *old_dir,
struct dentry *new_dentry,
unsigned int flags);
extern int __fscrypt_prepare_lookup(struct inode *dir, struct dentry *dentry);
+extern int __fscrypt_prepare_symlink(struct inode *dir, unsigned int len,
+ unsigned int max_len,
+ struct fscrypt_str *disk_link);
+extern int __fscrypt_encrypt_symlink(struct inode *inode, const char *target,
+ unsigned int len,
+ struct fscrypt_str *disk_link);
+extern const char *fscrypt_get_symlink(struct inode *inode, const void *caddr,
+ unsigned int max_size,
+ struct delayed_call *done);
#endif /* _LINUX_FSCRYPT_SUPP_H */