--- /dev/null
+/**
+ * eCryptfs: Linux filesystem encryption layer
+ *
+ * Copyright (C) 1997-2003 Erez Zadok
+ * Copyright (C) 2001-2003 Stony Brook University
+ * Copyright (C) 2004-2007 International Business Machines Corp.
+ * Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
+ * Michael C. Thompson <mcthomps@us.ibm.com>
+ * Tyler Hicks <tyhicks@ou.edu>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+#include <linux/dcache.h>
+#include <linux/file.h>
+#include <linux/module.h>
+#include <linux/namei.h>
+#include <linux/skbuff.h>
+#include <linux/crypto.h>
+#include <linux/mount.h>
+#include <linux/pagemap.h>
+#include <linux/key.h>
+#include <linux/parser.h>
+#include <linux/fs_stack.h>
+#include <linux/slab.h>
+#include <linux/magic.h>
+#include "ecryptfs_kernel.h"
+
+/**
+ * Module parameter that defines the ecryptfs_verbosity level.
+ */
+int ecryptfs_verbosity = 0;
+
+module_param(ecryptfs_verbosity, int, 0);
+MODULE_PARM_DESC(ecryptfs_verbosity,
+ "Initial verbosity level (0 or 1; defaults to "
+ "0, which is Quiet)");
+
+/**
+ * Module parameter that defines the number of message buffer elements
+ */
+unsigned int ecryptfs_message_buf_len = ECRYPTFS_DEFAULT_MSG_CTX_ELEMS;
+
+module_param(ecryptfs_message_buf_len, uint, 0);
+MODULE_PARM_DESC(ecryptfs_message_buf_len,
+ "Number of message buffer elements");
+
+/**
+ * Module parameter that defines the maximum guaranteed amount of time to wait
+ * for a response from ecryptfsd. The actual sleep time will be, more than
+ * likely, a small amount greater than this specified value, but only less if
+ * the message successfully arrives.
+ */
+signed long ecryptfs_message_wait_timeout = ECRYPTFS_MAX_MSG_CTX_TTL / HZ;
+
+module_param(ecryptfs_message_wait_timeout, long, 0);
+MODULE_PARM_DESC(ecryptfs_message_wait_timeout,
+ "Maximum number of seconds that an operation will "
+ "sleep while waiting for a message response from "
+ "userspace");
+
+/**
+ * Module parameter that is an estimate of the maximum number of users
+ * that will be concurrently using eCryptfs. Set this to the right
+ * value to balance performance and memory use.
+ */
+unsigned int ecryptfs_number_of_users = ECRYPTFS_DEFAULT_NUM_USERS;
+
+module_param(ecryptfs_number_of_users, uint, 0);
+MODULE_PARM_DESC(ecryptfs_number_of_users, "An estimate of the number of "
+ "concurrent users of eCryptfs");
+
+void __ecryptfs_printk(const char *fmt, ...)
+{
+ va_list args;
+ va_start(args, fmt);
+ if (fmt[1] == '7') { /* KERN_DEBUG */
+ if (ecryptfs_verbosity >= 1)
+ vprintk(fmt, args);
+ } else
+ vprintk(fmt, args);
+ va_end(args);
+}
+
+/**
+ * ecryptfs_init_lower_file
+ * @ecryptfs_dentry: Fully initialized eCryptfs dentry object, with
+ * the lower dentry and the lower mount set
+ *
+ * eCryptfs only ever keeps a single open file for every lower
+ * inode. All I/O operations to the lower inode occur through that
+ * file. When the first eCryptfs dentry that interposes with the first
+ * lower dentry for that inode is created, this function creates the
+ * lower file struct and associates it with the eCryptfs
+ * inode. When all eCryptfs files associated with the inode are released, the
+ * file is closed.
+ *
+ * The lower file will be opened with read/write permissions, if
+ * possible. Otherwise, it is opened read-only.
+ *
+ * This function does nothing if a lower file is already
+ * associated with the eCryptfs inode.
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+static int ecryptfs_init_lower_file(struct dentry *dentry,
+ struct file **lower_file)
+{
+ const struct cred *cred = current_cred();
+ struct path *path = ecryptfs_dentry_to_lower_path(dentry);
+ int rc;
+
+ rc = ecryptfs_privileged_open(lower_file, path->dentry, path->mnt,
+ cred);
+ if (rc) {
+ printk(KERN_ERR "Error opening lower file "
+ "for lower_dentry [0x%p] and lower_mnt [0x%p]; "
+ "rc = [%d]\n", path->dentry, path->mnt, rc);
+ (*lower_file) = NULL;
+ }
+ return rc;
+}
+
+int ecryptfs_get_lower_file(struct dentry *dentry, struct inode *inode)
+{
+ struct ecryptfs_inode_info *inode_info;
+ int count, rc = 0;
+
+ inode_info = ecryptfs_inode_to_private(inode);
+ mutex_lock(&inode_info->lower_file_mutex);
+ count = atomic_inc_return(&inode_info->lower_file_count);
+ if (WARN_ON_ONCE(count < 1))
+ rc = -EINVAL;
+ else if (count == 1) {
+ rc = ecryptfs_init_lower_file(dentry,
+ &inode_info->lower_file);
+ if (rc)
+ atomic_set(&inode_info->lower_file_count, 0);
+ }
+ mutex_unlock(&inode_info->lower_file_mutex);
+ return rc;
+}
+
+void ecryptfs_put_lower_file(struct inode *inode)
+{
+ struct ecryptfs_inode_info *inode_info;
+
+ inode_info = ecryptfs_inode_to_private(inode);
+ if (atomic_dec_and_mutex_lock(&inode_info->lower_file_count,
+ &inode_info->lower_file_mutex)) {
+ filemap_write_and_wait(inode->i_mapping);
+ fput(inode_info->lower_file);
+ inode_info->lower_file = NULL;
+ mutex_unlock(&inode_info->lower_file_mutex);
+ }
+}
+
+enum { ecryptfs_opt_sig, ecryptfs_opt_ecryptfs_sig,
+ ecryptfs_opt_cipher, ecryptfs_opt_ecryptfs_cipher,
+ ecryptfs_opt_ecryptfs_key_bytes,
+ ecryptfs_opt_passthrough, ecryptfs_opt_xattr_metadata,
+ ecryptfs_opt_encrypted_view, ecryptfs_opt_fnek_sig,
+ ecryptfs_opt_fn_cipher, ecryptfs_opt_fn_cipher_key_bytes,
+ ecryptfs_opt_unlink_sigs, ecryptfs_opt_mount_auth_tok_only,
+ ecryptfs_opt_check_dev_ruid,
+ ecryptfs_opt_err };
+
+static const match_table_t tokens = {
+ {ecryptfs_opt_sig, "sig=%s"},
+ {ecryptfs_opt_ecryptfs_sig, "ecryptfs_sig=%s"},
+ {ecryptfs_opt_cipher, "cipher=%s"},
+ {ecryptfs_opt_ecryptfs_cipher, "ecryptfs_cipher=%s"},
+ {ecryptfs_opt_ecryptfs_key_bytes, "ecryptfs_key_bytes=%u"},
+ {ecryptfs_opt_passthrough, "ecryptfs_passthrough"},
+ {ecryptfs_opt_xattr_metadata, "ecryptfs_xattr_metadata"},
+ {ecryptfs_opt_encrypted_view, "ecryptfs_encrypted_view"},
+ {ecryptfs_opt_fnek_sig, "ecryptfs_fnek_sig=%s"},
+ {ecryptfs_opt_fn_cipher, "ecryptfs_fn_cipher=%s"},
+ {ecryptfs_opt_fn_cipher_key_bytes, "ecryptfs_fn_key_bytes=%u"},
+ {ecryptfs_opt_unlink_sigs, "ecryptfs_unlink_sigs"},
+ {ecryptfs_opt_mount_auth_tok_only, "ecryptfs_mount_auth_tok_only"},
+ {ecryptfs_opt_check_dev_ruid, "ecryptfs_check_dev_ruid"},
+ {ecryptfs_opt_err, NULL}
+};
+
+static int ecryptfs_init_global_auth_toks(
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat)
+{
+ struct ecryptfs_global_auth_tok *global_auth_tok;
+ struct ecryptfs_auth_tok *auth_tok;
+ int rc = 0;
+
+ list_for_each_entry(global_auth_tok,
+ &mount_crypt_stat->global_auth_tok_list,
+ mount_crypt_stat_list) {
+ rc = ecryptfs_keyring_auth_tok_for_sig(
+ &global_auth_tok->global_auth_tok_key, &auth_tok,
+ global_auth_tok->sig);
+ if (rc) {
+ printk(KERN_ERR "Could not find valid key in user "
+ "session keyring for sig specified in mount "
+ "option: [%s]\n", global_auth_tok->sig);
+ global_auth_tok->flags |= ECRYPTFS_AUTH_TOK_INVALID;
+ goto out;
+ } else {
+ global_auth_tok->flags &= ~ECRYPTFS_AUTH_TOK_INVALID;
+ up_write(&(global_auth_tok->global_auth_tok_key)->sem);
+ }
+ }
+out:
+ return rc;
+}
+
+static void ecryptfs_init_mount_crypt_stat(
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat)
+{
+ memset((void *)mount_crypt_stat, 0,
+ sizeof(struct ecryptfs_mount_crypt_stat));
+ INIT_LIST_HEAD(&mount_crypt_stat->global_auth_tok_list);
+ mutex_init(&mount_crypt_stat->global_auth_tok_list_mutex);
+ mount_crypt_stat->flags |= ECRYPTFS_MOUNT_CRYPT_STAT_INITIALIZED;
+}
+
+/**
+ * ecryptfs_parse_options
+ * @sb: The ecryptfs super block
+ * @options: The options passed to the kernel
+ * @check_ruid: set to 1 if device uid should be checked against the ruid
+ *
+ * Parse mount options:
+ * debug=N - ecryptfs_verbosity level for debug output
+ * sig=XXX - description(signature) of the key to use
+ *
+ * Returns the dentry object of the lower-level (lower/interposed)
+ * directory; We want to mount our stackable file system on top of
+ * that lower directory.
+ *
+ * The signature of the key to use must be the description of a key
+ * already in the keyring. Mounting will fail if the key can not be
+ * found.
+ *
+ * Returns zero on success; non-zero on error
+ */
+static int ecryptfs_parse_options(struct ecryptfs_sb_info *sbi, char *options,
+ uid_t *check_ruid)
+{
+ char *p;
+ int rc = 0;
+ int sig_set = 0;
+ int cipher_name_set = 0;
+ int fn_cipher_name_set = 0;
+ int cipher_key_bytes;
+ int cipher_key_bytes_set = 0;
+ int fn_cipher_key_bytes;
+ int fn_cipher_key_bytes_set = 0;
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat =
+ &sbi->mount_crypt_stat;
+ substring_t args[MAX_OPT_ARGS];
+ int token;
+ char *sig_src;
+ char *cipher_name_dst;
+ char *cipher_name_src;
+ char *fn_cipher_name_dst;
+ char *fn_cipher_name_src;
+ char *fnek_dst;
+ char *fnek_src;
+ char *cipher_key_bytes_src;
+ char *fn_cipher_key_bytes_src;
+ u8 cipher_code;
+
+ *check_ruid = 0;
+
+ if (!options) {
+ rc = -EINVAL;
+ goto out;
+ }
+ ecryptfs_init_mount_crypt_stat(mount_crypt_stat);
+ while ((p = strsep(&options, ",")) != NULL) {
+ if (!*p)
+ continue;
+ token = match_token(p, tokens, args);
+ switch (token) {
+ case ecryptfs_opt_sig:
+ case ecryptfs_opt_ecryptfs_sig:
+ sig_src = args[0].from;
+ rc = ecryptfs_add_global_auth_tok(mount_crypt_stat,
+ sig_src, 0);
+ if (rc) {
+ printk(KERN_ERR "Error attempting to register "
+ "global sig; rc = [%d]\n", rc);
+ goto out;
+ }
+ sig_set = 1;
+ break;
+ case ecryptfs_opt_cipher:
+ case ecryptfs_opt_ecryptfs_cipher:
+ cipher_name_src = args[0].from;
+ cipher_name_dst =
+ mount_crypt_stat->
+ global_default_cipher_name;
+ strncpy(cipher_name_dst, cipher_name_src,
+ ECRYPTFS_MAX_CIPHER_NAME_SIZE);
+ cipher_name_dst[ECRYPTFS_MAX_CIPHER_NAME_SIZE] = '\0';
+ cipher_name_set = 1;
+ break;
+ case ecryptfs_opt_ecryptfs_key_bytes:
+ cipher_key_bytes_src = args[0].from;
+ cipher_key_bytes =
+ (int)simple_strtol(cipher_key_bytes_src,
+ &cipher_key_bytes_src, 0);
+ mount_crypt_stat->global_default_cipher_key_size =
+ cipher_key_bytes;
+ cipher_key_bytes_set = 1;
+ break;
+ case ecryptfs_opt_passthrough:
+ mount_crypt_stat->flags |=
+ ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED;
+ break;
+ case ecryptfs_opt_xattr_metadata:
+ mount_crypt_stat->flags |=
+ ECRYPTFS_XATTR_METADATA_ENABLED;
+ break;
+ case ecryptfs_opt_encrypted_view:
+ mount_crypt_stat->flags |=
+ ECRYPTFS_XATTR_METADATA_ENABLED;
+ mount_crypt_stat->flags |=
+ ECRYPTFS_ENCRYPTED_VIEW_ENABLED;
+ break;
+ case ecryptfs_opt_fnek_sig:
+ fnek_src = args[0].from;
+ fnek_dst =
+ mount_crypt_stat->global_default_fnek_sig;
+ strncpy(fnek_dst, fnek_src, ECRYPTFS_SIG_SIZE_HEX);
+ mount_crypt_stat->global_default_fnek_sig[
+ ECRYPTFS_SIG_SIZE_HEX] = '\0';
+ rc = ecryptfs_add_global_auth_tok(
+ mount_crypt_stat,
+ mount_crypt_stat->global_default_fnek_sig,
+ ECRYPTFS_AUTH_TOK_FNEK);
+ if (rc) {
+ printk(KERN_ERR "Error attempting to register "
+ "global fnek sig [%s]; rc = [%d]\n",
+ mount_crypt_stat->global_default_fnek_sig,
+ rc);
+ goto out;
+ }
+ mount_crypt_stat->flags |=
+ (ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES
+ | ECRYPTFS_GLOBAL_ENCFN_USE_MOUNT_FNEK);
+ break;
+ case ecryptfs_opt_fn_cipher:
+ fn_cipher_name_src = args[0].from;
+ fn_cipher_name_dst =
+ mount_crypt_stat->global_default_fn_cipher_name;
+ strncpy(fn_cipher_name_dst, fn_cipher_name_src,
+ ECRYPTFS_MAX_CIPHER_NAME_SIZE);
+ mount_crypt_stat->global_default_fn_cipher_name[
+ ECRYPTFS_MAX_CIPHER_NAME_SIZE] = '\0';
+ fn_cipher_name_set = 1;
+ break;
+ case ecryptfs_opt_fn_cipher_key_bytes:
+ fn_cipher_key_bytes_src = args[0].from;
+ fn_cipher_key_bytes =
+ (int)simple_strtol(fn_cipher_key_bytes_src,
+ &fn_cipher_key_bytes_src, 0);
+ mount_crypt_stat->global_default_fn_cipher_key_bytes =
+ fn_cipher_key_bytes;
+ fn_cipher_key_bytes_set = 1;
+ break;
+ case ecryptfs_opt_unlink_sigs:
+ mount_crypt_stat->flags |= ECRYPTFS_UNLINK_SIGS;
+ break;
+ case ecryptfs_opt_mount_auth_tok_only:
+ mount_crypt_stat->flags |=
+ ECRYPTFS_GLOBAL_MOUNT_AUTH_TOK_ONLY;
+ break;
+ case ecryptfs_opt_check_dev_ruid:
+ *check_ruid = 1;
+ break;
+ case ecryptfs_opt_err:
+ default:
+ printk(KERN_WARNING
+ "%s: eCryptfs: unrecognized option [%s]\n",
+ __func__, p);
+ }
+ }
+ if (!sig_set) {
+ rc = -EINVAL;
+ ecryptfs_printk(KERN_ERR, "You must supply at least one valid "
+ "auth tok signature as a mount "
+ "parameter; see the eCryptfs README\n");
+ goto out;
+ }
+ if (!cipher_name_set) {
+ int cipher_name_len = strlen(ECRYPTFS_DEFAULT_CIPHER);
+
+ BUG_ON(cipher_name_len > ECRYPTFS_MAX_CIPHER_NAME_SIZE);
+ strcpy(mount_crypt_stat->global_default_cipher_name,
+ ECRYPTFS_DEFAULT_CIPHER);
+ }
+ if ((mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES)
+ && !fn_cipher_name_set)
+ strcpy(mount_crypt_stat->global_default_fn_cipher_name,
+ mount_crypt_stat->global_default_cipher_name);
+ if (!cipher_key_bytes_set)
+ mount_crypt_stat->global_default_cipher_key_size = 0;
+ if ((mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES)
+ && !fn_cipher_key_bytes_set)
+ mount_crypt_stat->global_default_fn_cipher_key_bytes =
+ mount_crypt_stat->global_default_cipher_key_size;
+
+ cipher_code = ecryptfs_code_for_cipher_string(
+ mount_crypt_stat->global_default_cipher_name,
+ mount_crypt_stat->global_default_cipher_key_size);
+ if (!cipher_code) {
+ ecryptfs_printk(KERN_ERR,
+ "eCryptfs doesn't support cipher: %s",
+ mount_crypt_stat->global_default_cipher_name);
+ rc = -EINVAL;
+ goto out;
+ }
+
+ mutex_lock(&key_tfm_list_mutex);
+ if (!ecryptfs_tfm_exists(mount_crypt_stat->global_default_cipher_name,
+ NULL)) {
+ rc = ecryptfs_add_new_key_tfm(
+ NULL, mount_crypt_stat->global_default_cipher_name,
+ mount_crypt_stat->global_default_cipher_key_size);
+ if (rc) {
+ printk(KERN_ERR "Error attempting to initialize "
+ "cipher with name = [%s] and key size = [%td]; "
+ "rc = [%d]\n",
+ mount_crypt_stat->global_default_cipher_name,
+ mount_crypt_stat->global_default_cipher_key_size,
+ rc);
+ rc = -EINVAL;
+ mutex_unlock(&key_tfm_list_mutex);
+ goto out;
+ }
+ }
+ if ((mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES)
+ && !ecryptfs_tfm_exists(
+ mount_crypt_stat->global_default_fn_cipher_name, NULL)) {
+ rc = ecryptfs_add_new_key_tfm(
+ NULL, mount_crypt_stat->global_default_fn_cipher_name,
+ mount_crypt_stat->global_default_fn_cipher_key_bytes);
+ if (rc) {
+ printk(KERN_ERR "Error attempting to initialize "
+ "cipher with name = [%s] and key size = [%td]; "
+ "rc = [%d]\n",
+ mount_crypt_stat->global_default_fn_cipher_name,
+ mount_crypt_stat->global_default_fn_cipher_key_bytes,
+ rc);
+ rc = -EINVAL;
+ mutex_unlock(&key_tfm_list_mutex);
+ goto out;
+ }
+ }
+ mutex_unlock(&key_tfm_list_mutex);
+ rc = ecryptfs_init_global_auth_toks(mount_crypt_stat);
+ if (rc)
+ printk(KERN_WARNING "One or more global auth toks could not "
+ "properly register; rc = [%d]\n", rc);
+out:
+ return rc;
+}
+
+struct kmem_cache *ecryptfs_sb_info_cache;
+static struct file_system_type ecryptfs_fs_type;
+
+/**
+ * ecryptfs_get_sb
+ * @fs_type
+ * @flags
+ * @dev_name: The path to mount over
+ * @raw_data: The options passed into the kernel
+ */
+static struct dentry *ecryptfs_mount(struct file_system_type *fs_type, int flags,
+ const char *dev_name, void *raw_data)
+{
+ struct super_block *s;
+ struct ecryptfs_sb_info *sbi;
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
+ struct ecryptfs_dentry_info *root_info;
+ const char *err = "Getting sb failed";
+ struct inode *inode;
+ struct path path;
+ uid_t check_ruid;
+ int rc;
+
+ sbi = kmem_cache_zalloc(ecryptfs_sb_info_cache, GFP_KERNEL);
+ if (!sbi) {
+ rc = -ENOMEM;
+ goto out;
+ }
+
+ rc = ecryptfs_parse_options(sbi, raw_data, &check_ruid);
+ if (rc) {
+ err = "Error parsing options";
+ goto out;
+ }
+ mount_crypt_stat = &sbi->mount_crypt_stat;
+
+ s = sget(fs_type, NULL, set_anon_super, flags, NULL);
+ if (IS_ERR(s)) {
+ rc = PTR_ERR(s);
+ goto out;
+ }
+
+ rc = bdi_setup_and_register(&sbi->bdi, "ecryptfs");
+ if (rc)
+ goto out1;
+
+ ecryptfs_set_superblock_private(s, sbi);
+ s->s_bdi = &sbi->bdi;
+
+ /* ->kill_sb() will take care of sbi after that point */
+ sbi = NULL;
+ s->s_op = &ecryptfs_sops;
+ s->s_d_op = &ecryptfs_dops;
+
+ err = "Reading sb failed";
+ rc = kern_path(dev_name, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path);
+ if (rc) {
+ ecryptfs_printk(KERN_WARNING, "kern_path() failed\n");
+ goto out1;
+ }
+ if (path.dentry->d_sb->s_type == &ecryptfs_fs_type) {
+ rc = -EINVAL;
+ printk(KERN_ERR "Mount on filesystem of type "
+ "eCryptfs explicitly disallowed due to "
+ "known incompatibilities\n");
+ goto out_free;
+ }
+
+ if (check_ruid && !uid_eq(d_inode(path.dentry)->i_uid, current_uid())) {
+ rc = -EPERM;
+ printk(KERN_ERR "Mount of device (uid: %d) not owned by "
+ "requested user (uid: %d)\n",
+ i_uid_read(d_inode(path.dentry)),
+ from_kuid(&init_user_ns, current_uid()));
+ goto out_free;
+ }
+
+ ecryptfs_set_superblock_lower(s, path.dentry->d_sb);
+
+ /**
+ * Set the POSIX ACL flag based on whether they're enabled in the lower
+ * mount.
+ */
+ s->s_flags = flags & ~MS_POSIXACL;
+ s->s_flags |= path.dentry->d_sb->s_flags & MS_POSIXACL;
+
+ /**
+ * Force a read-only eCryptfs mount when:
+ * 1) The lower mount is ro
+ * 2) The ecryptfs_encrypted_view mount option is specified
+ */
+ if (path.dentry->d_sb->s_flags & MS_RDONLY ||
+ mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED)
+ s->s_flags |= MS_RDONLY;
+
+ s->s_maxbytes = path.dentry->d_sb->s_maxbytes;
+ s->s_blocksize = path.dentry->d_sb->s_blocksize;
+ s->s_magic = ECRYPTFS_SUPER_MAGIC;
+ s->s_stack_depth = path.dentry->d_sb->s_stack_depth + 1;
+
+ rc = -EINVAL;
+ if (s->s_stack_depth > FILESYSTEM_MAX_STACK_DEPTH) {
+ pr_err("eCryptfs: maximum fs stacking depth exceeded\n");
+ goto out_free;
+ }
+
+ inode = ecryptfs_get_inode(d_inode(path.dentry), s);
+ rc = PTR_ERR(inode);
+ if (IS_ERR(inode))
+ goto out_free;
+
+ s->s_root = d_make_root(inode);
+ if (!s->s_root) {
+ rc = -ENOMEM;
+ goto out_free;
+ }
+
+ rc = -ENOMEM;
+ root_info = kmem_cache_zalloc(ecryptfs_dentry_info_cache, GFP_KERNEL);
+ if (!root_info)
+ goto out_free;
+
+ /* ->kill_sb() will take care of root_info */
+ ecryptfs_set_dentry_private(s->s_root, root_info);
+ root_info->lower_path = path;
+
+ s->s_flags |= MS_ACTIVE;
+ return dget(s->s_root);
+
+out_free:
+ path_put(&path);
+out1:
+ deactivate_locked_super(s);
+out:
+ if (sbi) {
+ ecryptfs_destroy_mount_crypt_stat(&sbi->mount_crypt_stat);
+ kmem_cache_free(ecryptfs_sb_info_cache, sbi);
+ }
+ printk(KERN_ERR "%s; rc = [%d]\n", err, rc);
+ return ERR_PTR(rc);
+}
+
+/**
+ * ecryptfs_kill_block_super
+ * @sb: The ecryptfs super block
+ *
+ * Used to bring the superblock down and free the private data.
+ */
+static void ecryptfs_kill_block_super(struct super_block *sb)
+{
+ struct ecryptfs_sb_info *sb_info = ecryptfs_superblock_to_private(sb);
+ kill_anon_super(sb);
+ if (!sb_info)
+ return;
+ ecryptfs_destroy_mount_crypt_stat(&sb_info->mount_crypt_stat);
+ bdi_destroy(&sb_info->bdi);
+ kmem_cache_free(ecryptfs_sb_info_cache, sb_info);
+}
+
+static struct file_system_type ecryptfs_fs_type = {
+ .owner = THIS_MODULE,
+ .name = "ecryptfs",
+ .mount = ecryptfs_mount,
+ .kill_sb = ecryptfs_kill_block_super,
+ .fs_flags = 0
+};
+MODULE_ALIAS_FS("ecryptfs");
+
+/**
+ * inode_info_init_once
+ *
+ * Initializes the ecryptfs_inode_info_cache when it is created
+ */
+static void
+inode_info_init_once(void *vptr)
+{
+ struct ecryptfs_inode_info *ei = (struct ecryptfs_inode_info *)vptr;
+
+ inode_init_once(&ei->vfs_inode);
+}
+
+static struct ecryptfs_cache_info {
+ struct kmem_cache **cache;
+ const char *name;
+ size_t size;
+ void (*ctor)(void *obj);
+} ecryptfs_cache_infos[] = {
+ {
+ .cache = &ecryptfs_auth_tok_list_item_cache,
+ .name = "ecryptfs_auth_tok_list_item",
+ .size = sizeof(struct ecryptfs_auth_tok_list_item),
+ },
+ {
+ .cache = &ecryptfs_file_info_cache,
+ .name = "ecryptfs_file_cache",
+ .size = sizeof(struct ecryptfs_file_info),
+ },
+ {
+ .cache = &ecryptfs_dentry_info_cache,
+ .name = "ecryptfs_dentry_info_cache",
+ .size = sizeof(struct ecryptfs_dentry_info),
+ },
+ {
+ .cache = &ecryptfs_inode_info_cache,
+ .name = "ecryptfs_inode_cache",
+ .size = sizeof(struct ecryptfs_inode_info),
+ .ctor = inode_info_init_once,
+ },
+ {
+ .cache = &ecryptfs_sb_info_cache,
+ .name = "ecryptfs_sb_cache",
+ .size = sizeof(struct ecryptfs_sb_info),
+ },
+ {
+ .cache = &ecryptfs_header_cache,
+ .name = "ecryptfs_headers",
+ .size = PAGE_CACHE_SIZE,
+ },
+ {
+ .cache = &ecryptfs_xattr_cache,
+ .name = "ecryptfs_xattr_cache",
+ .size = PAGE_CACHE_SIZE,
+ },
+ {
+ .cache = &ecryptfs_key_record_cache,
+ .name = "ecryptfs_key_record_cache",
+ .size = sizeof(struct ecryptfs_key_record),
+ },
+ {
+ .cache = &ecryptfs_key_sig_cache,
+ .name = "ecryptfs_key_sig_cache",
+ .size = sizeof(struct ecryptfs_key_sig),
+ },
+ {
+ .cache = &ecryptfs_global_auth_tok_cache,
+ .name = "ecryptfs_global_auth_tok_cache",
+ .size = sizeof(struct ecryptfs_global_auth_tok),
+ },
+ {
+ .cache = &ecryptfs_key_tfm_cache,
+ .name = "ecryptfs_key_tfm_cache",
+ .size = sizeof(struct ecryptfs_key_tfm),
+ },
+};
+
+static void ecryptfs_free_kmem_caches(void)
+{
+ int i;
+
+ /*
+ * Make sure all delayed rcu free inodes are flushed before we
+ * destroy cache.
+ */
+ rcu_barrier();
+
+ for (i = 0; i < ARRAY_SIZE(ecryptfs_cache_infos); i++) {
+ struct ecryptfs_cache_info *info;
+
+ info = &ecryptfs_cache_infos[i];
+ if (*(info->cache))
+ kmem_cache_destroy(*(info->cache));
+ }
+}
+
+/**
+ * ecryptfs_init_kmem_caches
+ *
+ * Returns zero on success; non-zero otherwise
+ */
+static int ecryptfs_init_kmem_caches(void)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(ecryptfs_cache_infos); i++) {
+ struct ecryptfs_cache_info *info;
+
+ info = &ecryptfs_cache_infos[i];
+ *(info->cache) = kmem_cache_create(info->name, info->size,
+ 0, SLAB_HWCACHE_ALIGN, info->ctor);
+ if (!*(info->cache)) {
+ ecryptfs_free_kmem_caches();
+ ecryptfs_printk(KERN_WARNING, "%s: "
+ "kmem_cache_create failed\n",
+ info->name);
+ return -ENOMEM;
+ }
+ }
+ return 0;
+}
+
+static struct kobject *ecryptfs_kobj;
+
+static ssize_t version_show(struct kobject *kobj,
+ struct kobj_attribute *attr, char *buff)
+{
+ return snprintf(buff, PAGE_SIZE, "%d\n", ECRYPTFS_VERSIONING_MASK);
+}
+
+static struct kobj_attribute version_attr = __ATTR_RO(version);
+
+static struct attribute *attributes[] = {
+ &version_attr.attr,
+ NULL,
+};
+
+static struct attribute_group attr_group = {
+ .attrs = attributes,
+};
+
+static int do_sysfs_registration(void)
+{
+ int rc;
+
+ ecryptfs_kobj = kobject_create_and_add("ecryptfs", fs_kobj);
+ if (!ecryptfs_kobj) {
+ printk(KERN_ERR "Unable to create ecryptfs kset\n");
+ rc = -ENOMEM;
+ goto out;
+ }
+ rc = sysfs_create_group(ecryptfs_kobj, &attr_group);
+ if (rc) {
+ printk(KERN_ERR
+ "Unable to create ecryptfs version attributes\n");
+ kobject_put(ecryptfs_kobj);
+ }
+out:
+ return rc;
+}
+
+static void do_sysfs_unregistration(void)
+{
+ sysfs_remove_group(ecryptfs_kobj, &attr_group);
+ kobject_put(ecryptfs_kobj);
+}
+
+static int __init ecryptfs_init(void)
+{
+ int rc;
+
+ if (ECRYPTFS_DEFAULT_EXTENT_SIZE > PAGE_CACHE_SIZE) {
+ rc = -EINVAL;
+ ecryptfs_printk(KERN_ERR, "The eCryptfs extent size is "
+ "larger than the host's page size, and so "
+ "eCryptfs cannot run on this system. The "
+ "default eCryptfs extent size is [%u] bytes; "
+ "the page size is [%lu] bytes.\n",
+ ECRYPTFS_DEFAULT_EXTENT_SIZE,
+ (unsigned long)PAGE_CACHE_SIZE);
+ goto out;
+ }
+ rc = ecryptfs_init_kmem_caches();
+ if (rc) {
+ printk(KERN_ERR
+ "Failed to allocate one or more kmem_cache objects\n");
+ goto out;
+ }
+ rc = do_sysfs_registration();
+ if (rc) {
+ printk(KERN_ERR "sysfs registration failed\n");
+ goto out_free_kmem_caches;
+ }
+ rc = ecryptfs_init_kthread();
+ if (rc) {
+ printk(KERN_ERR "%s: kthread initialization failed; "
+ "rc = [%d]\n", __func__, rc);
+ goto out_do_sysfs_unregistration;
+ }
+ rc = ecryptfs_init_messaging();
+ if (rc) {
+ printk(KERN_ERR "Failure occurred while attempting to "
+ "initialize the communications channel to "
+ "ecryptfsd\n");
+ goto out_destroy_kthread;
+ }
+ rc = ecryptfs_init_crypto();
+ if (rc) {
+ printk(KERN_ERR "Failure whilst attempting to init crypto; "
+ "rc = [%d]\n", rc);
+ goto out_release_messaging;
+ }
+ rc = register_filesystem(&ecryptfs_fs_type);
+ if (rc) {
+ printk(KERN_ERR "Failed to register filesystem\n");
+ goto out_destroy_crypto;
+ }
+ if (ecryptfs_verbosity > 0)
+ printk(KERN_CRIT "eCryptfs verbosity set to %d. Secret values "
+ "will be written to the syslog!\n", ecryptfs_verbosity);
+
+ goto out;
+out_destroy_crypto:
+ ecryptfs_destroy_crypto();
+out_release_messaging:
+ ecryptfs_release_messaging();
+out_destroy_kthread:
+ ecryptfs_destroy_kthread();
+out_do_sysfs_unregistration:
+ do_sysfs_unregistration();
+out_free_kmem_caches:
+ ecryptfs_free_kmem_caches();
+out:
+ return rc;
+}
+
+static void __exit ecryptfs_exit(void)
+{
+ int rc;
+
+ rc = ecryptfs_destroy_crypto();
+ if (rc)
+ printk(KERN_ERR "Failure whilst attempting to destroy crypto; "
+ "rc = [%d]\n", rc);
+ ecryptfs_release_messaging();
+ ecryptfs_destroy_kthread();
+ do_sysfs_unregistration();
+ unregister_filesystem(&ecryptfs_fs_type);
+ ecryptfs_free_kmem_caches();
+}
+
+MODULE_AUTHOR("Michael A. Halcrow <mhalcrow@us.ibm.com>");
+MODULE_DESCRIPTION("eCryptfs");
+
+MODULE_LICENSE("GPL");
+
+module_init(ecryptfs_init)
+module_exit(ecryptfs_exit)
Code Review / kvmfornfv.git / blobdiff