fs/crypto/hooks.c

201  * fscrypt_prepare_symlink() - prepare to create a possibly-encrypted symlink
202  * @dir: directory in which the symlink is being created
203  * @target: plaintext symlink target
205  * @max_len: space the filesystem has available to store the symlink target
206  * @disk_link: (out) the on-disk symlink target being prepared
208  * This function computes the size the symlink target will require on-disk,
210  * encrypted symlink may be longer than the original.
212  * Additionally, @disk_link->name is set to @target if the symlink will be
213  * unencrypted, but left NULL if the symlink will be encrypted.  For encrypted
216  * filesystems need to know the size of the symlink target before creating the
217  * inode, e.g. to determine whether it will be a "fast" or "slow" symlink.)
219  * Return: 0 on success, -ENAMETOOLONG if the symlink target is too long,
230 	 * To calculate the size of the encrypted symlink target we need to know  in fscrypt_prepare_symlink()
247 	 * Calculate the size of the encrypted symlink and verify it won't  in fscrypt_prepare_symlink()
248 	 * exceed max_len.  Note that for historical reasons, encrypted symlink  in fscrypt_prepare_symlink()
251 	 * longest symlink target we can accept.  in fscrypt_prepare_symlink()
278 	 * symlink inode's encryption key.  We don't wait until now to do it,  in __fscrypt_encrypt_symlink()
307 	/* Cache the plaintext symlink target for later use by get_link() */  in __fscrypt_encrypt_symlink()
325  * fscrypt_get_symlink() - get the target of an encrypted symlink
326  * @inode: the symlink inode
327  * @caddr: the on-disk contents of the symlink
331  * If the symlink's encryption key is available, we decrypt its target.
336  * Return: the presentable symlink target or an ERR_PTR()
357 	 * Try to set up the symlink's encryption key, but we can continue  in fscrypt_get_symlink()
366 	 * For historical reasons, encrypted symlink targets are prefixed with  in fscrypt_get_symlink()
397 	 * Cache decrypted symlink targets in i_link for later use.  Don't cache  in fscrypt_get_symlink()
398 	 * symlink targets encoded without the key, since those become outdated  in fscrypt_get_symlink()
416  * @path: the path for the encrypted symlink being queried
417  * @stat: the struct being filled with the symlink's attributes
420  * symlink target (or the no-key encoded symlink target, if the key is
421  * unavailable) rather than the length of the encrypted symlink target.  This is
422  * necessary for st_size to match the symlink target that userspace actually
425  * This requires reading the symlink target from disk if needed, setting up the
427  * symlink target.  This makes lstat() more heavyweight than is normally the
428  * case.  However, decrypted symlink targets will be cached in ->i_link, so
429  * usually the symlink won't have to be read and decrypted again later if/when
442 	 * To get the symlink target that userspace will see (whether it's the  in fscrypt_symlink_getattr()