Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754475AbYKDVmk (ORCPT ); Tue, 4 Nov 2008 16:42:40 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754368AbYKDVm2 (ORCPT ); Tue, 4 Nov 2008 16:42:28 -0500 Received: from e38.co.us.ibm.com ([32.97.110.159]:38238 "EHLO e38.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754267AbYKDVm1 (ORCPT ); Tue, 4 Nov 2008 16:42:27 -0500 Date: Tue, 4 Nov 2008 15:42:23 -0600 From: Michael Halcrow To: Andrew Morton Cc: LKML , Dustin Kirkland , Eric Sandeen , Tyler Hicks , David Kleikamp Subject: [PATCH 4/5] eCryptfs: Filename Encryption: filldir, lookup, and readlink Message-ID: <20081104214223.GD6677@halcrowt61p.austin.ibm.com> Reply-To: Michael Halcrow References: <20081104213754.GC6675@halcrowt61p.austin.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20081104213754.GC6675@halcrowt61p.austin.ibm.com> User-Agent: Mutt/1.5.16 (2007-06-09) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 23270 Lines: 660 Make the requisite modifications to ecryptfs_filldir(), ecryptfs_lookup(), and ecryptfs_readlink() to call out to filename encryption functions. Propagate filename encryption policy flags from mount-wide crypt_stat to inode crypt_stat. Signed-off-by: Michael Halcrow --- fs/ecryptfs/crypto.c | 107 ++------------- fs/ecryptfs/ecryptfs_kernel.h | 6 - fs/ecryptfs/file.c | 30 ++-- fs/ecryptfs/inode.c | 294 +++++++++++++++++++++++------------------ 4 files changed, 195 insertions(+), 242 deletions(-) diff --git a/fs/ecryptfs/crypto.c b/fs/ecryptfs/crypto.c index 18c78ab..ea2afd2 100644 --- a/fs/ecryptfs/crypto.c +++ b/fs/ecryptfs/crypto.c @@ -924,6 +924,15 @@ static void ecryptfs_copy_mount_wide_flags_to_inode_flags( crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR; if (mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED) crypt_stat->flags |= ECRYPTFS_VIEW_AS_ENCRYPTED; + if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) { + crypt_stat->flags |= ECRYPTFS_ENCRYPT_FILENAMES; + if (mount_crypt_stat->flags + & ECRYPTFS_GLOBAL_ENCFN_USE_MOUNT_FNEK) + crypt_stat->flags |= ECRYPTFS_ENCFN_USE_MOUNT_FNEK; + else if (mount_crypt_stat->flags + & ECRYPTFS_GLOBAL_ENCFN_USE_FEK) + crypt_stat->flags |= ECRYPTFS_ENCFN_USE_FEK; + } } static int ecryptfs_copy_mount_wide_sigs_to_inode_sigs( @@ -1060,7 +1069,8 @@ struct ecryptfs_flag_map_elem { static struct ecryptfs_flag_map_elem ecryptfs_flag_map[] = { {0x00000001, ECRYPTFS_ENABLE_HMAC}, {0x00000002, ECRYPTFS_ENCRYPTED}, - {0x00000004, ECRYPTFS_METADATA_IN_XATTR} + {0x00000004, ECRYPTFS_METADATA_IN_XATTR}, + {0x00000008, ECRYPTFS_ENCRYPT_FILENAMES} }; /** @@ -1213,6 +1223,8 @@ int ecryptfs_read_and_validate_header_region(char *data, &(ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat); int rc; + if (crypt_stat->extent_size == 0) + crypt_stat->extent_size = ECRYPTFS_DEFAULT_EXTENT_SIZE; rc = ecryptfs_read_lower(data, 0, crypt_stat->extent_size, ecryptfs_inode); if (rc) { @@ -1222,7 +1234,6 @@ int ecryptfs_read_and_validate_header_region(char *data, } if (!contains_ecryptfs_marker(data + ECRYPTFS_FILE_SIZE_BYTES)) { rc = -EINVAL; - ecryptfs_printk(KERN_DEBUG, "Valid marker not found\n"); } out: return rc; @@ -1629,98 +1640,6 @@ out: } /** - * ecryptfs_encode_filename - converts a plaintext file name to cipher text - * @crypt_stat: The crypt_stat struct associated with the file anem to encode - * @name: The plaintext name - * @length: The length of the plaintext - * @encoded_name: The encypted name - * - * Encrypts and encodes a filename into something that constitutes a - * valid filename for a filesystem, with printable characters. - * - * We assume that we have a properly initialized crypto context, - * pointed to by crypt_stat->tfm. - * - * TODO: Implement filename decoding and decryption here, in place of - * memcpy. We are keeping the framework around for now to (1) - * facilitate testing of the components needed to implement filename - * encryption and (2) to provide a code base from which other - * developers in the community can easily implement this feature. - * - * Returns the length of encoded filename; negative if error - */ -int -ecryptfs_encode_filename(struct ecryptfs_crypt_stat *crypt_stat, - const char *name, int length, char **encoded_name) -{ - int error = 0; - - (*encoded_name) = kmalloc(length + 2, GFP_KERNEL); - if (!(*encoded_name)) { - error = -ENOMEM; - goto out; - } - /* TODO: Filename encryption is a scheduled feature for a - * future version of eCryptfs. This function is here only for - * the purpose of providing a framework for other developers - * to easily implement filename encryption. Hint: Replace this - * memcpy() with a call to encrypt and encode the - * filename, the set the length accordingly. */ - memcpy((void *)(*encoded_name), (void *)name, length); - (*encoded_name)[length] = '\0'; - error = length + 1; -out: - return error; -} - -/** - * ecryptfs_decode_filename - converts the cipher text name to plaintext - * @crypt_stat: The crypt_stat struct associated with the file - * @name: The filename in cipher text - * @length: The length of the cipher text name - * @decrypted_name: The plaintext name - * - * Decodes and decrypts the filename. - * - * We assume that we have a properly initialized crypto context, - * pointed to by crypt_stat->tfm. - * - * TODO: Implement filename decoding and decryption here, in place of - * memcpy. We are keeping the framework around for now to (1) - * facilitate testing of the components needed to implement filename - * encryption and (2) to provide a code base from which other - * developers in the community can easily implement this feature. - * - * Returns the length of decoded filename; negative if error - */ -int -ecryptfs_decode_filename(struct ecryptfs_crypt_stat *crypt_stat, - const char *name, int length, char **decrypted_name) -{ - int error = 0; - - (*decrypted_name) = kmalloc(length + 2, GFP_KERNEL); - if (!(*decrypted_name)) { - error = -ENOMEM; - goto out; - } - /* TODO: Filename encryption is a scheduled feature for a - * future version of eCryptfs. This function is here only for - * the purpose of providing a framework for other developers - * to easily implement filename encryption. Hint: Replace this - * memcpy() with a call to decode and decrypt the - * filename, the set the length accordingly. */ - memcpy((void *)(*decrypted_name), (void *)name, length); - (*decrypted_name)[length + 1] = '\0'; /* Only for convenience - * in printing out the - * string in debug - * messages */ - error = length; -out: - return error; -} - -/** * ecryptfs_encrypt_filename - encrypt filename * * CBC-encrypts the filename. We do not want to encrypt the same diff --git a/fs/ecryptfs/ecryptfs_kernel.h b/fs/ecryptfs/ecryptfs_kernel.h index b648175..c11fc95 100644 --- a/fs/ecryptfs/ecryptfs_kernel.h +++ b/fs/ecryptfs/ecryptfs_kernel.h @@ -627,12 +627,6 @@ int ecryptfs_decode_and_decrypt_filename(char **decrypted_name, struct dentry *ecryptfs_dentry, const char *name, size_t name_size); int ecryptfs_fill_zeros(struct file *file, loff_t new_length); -int ecryptfs_decode_filename(struct ecryptfs_crypt_stat *crypt_stat, - const char *name, int length, - char **decrypted_name); -int ecryptfs_encode_filename(struct ecryptfs_crypt_stat *crypt_stat, - const char *name, int length, - char **encoded_name); int ecryptfs_encrypt_and_encode_filename( char **encoded_name, size_t *encoded_name_size, diff --git a/fs/ecryptfs/file.c b/fs/ecryptfs/file.c index eb3dc4c..6b0a99d 100644 --- a/fs/ecryptfs/file.c +++ b/fs/ecryptfs/file.c @@ -77,27 +77,27 @@ struct ecryptfs_getdents_callback { /* Inspired by generic filldir in fs/readdir.c */ static int -ecryptfs_filldir(void *dirent, const char *name, int namelen, loff_t offset, - u64 ino, unsigned int d_type) +ecryptfs_filldir(void *dirent, const char *lower_name, int lower_namelen, + loff_t offset, u64 ino, unsigned int d_type) { - struct ecryptfs_crypt_stat *crypt_stat; struct ecryptfs_getdents_callback *buf = (struct ecryptfs_getdents_callback *)dirent; + int name_size; + char *name; int rc; - int decoded_length; - char *decoded_name; - crypt_stat = ecryptfs_dentry_to_private(buf->dentry)->crypt_stat; buf->filldir_called++; - decoded_length = ecryptfs_decode_filename(crypt_stat, name, namelen, - &decoded_name); - if (decoded_length < 0) { - rc = decoded_length; + rc = ecryptfs_decode_and_decrypt_filename(&name, &name_size, + buf->dentry, lower_name, + lower_namelen); + if (rc) { + printk(KERN_ERR "%s: Error attempting to decode and decrypt " + "filename [%s]; rc = [%d]\n", __func__, lower_name, + rc); goto out; } - rc = buf->filldir(buf->dirent, decoded_name, decoded_length, offset, - ino, d_type); - kfree(decoded_name); + rc = buf->filldir(buf->dirent, name, name_size, offset, ino, d_type); + kfree(name); if (rc >= 0) buf->entries_written++; out: @@ -106,8 +106,8 @@ out: /** * ecryptfs_readdir - * @file: The ecryptfs file struct - * @dirent: Directory entry + * @file: The eCryptfs directory file + * @dirent: Directory entry handle * @filldir: The filldir callback function */ static int ecryptfs_readdir(struct file *file, void *dirent, filldir_t filldir) diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c index 89209f0..cf50729 100644 --- a/fs/ecryptfs/inode.c +++ b/fs/ecryptfs/inode.c @@ -228,8 +228,7 @@ ecryptfs_create(struct inode *directory_inode, struct dentry *ecryptfs_dentry, { int rc; - /* ecryptfs_do_create() calls ecryptfs_interpose(), which opens - * the crypt_stat->lower_file (persistent file) */ + /* ecryptfs_do_create() calls ecryptfs_interpose() */ rc = ecryptfs_do_create(directory_inode, ecryptfs_dentry, mode, nd); if (unlikely(rc)) { ecryptfs_printk(KERN_WARNING, "Failed to create file in" @@ -244,141 +243,91 @@ out: } /** - * ecryptfs_lookup - * @dir: inode - * @dentry: The dentry - * @nd: nameidata, may be NULL - * - * Find a file on disk. If the file does not exist, then we'll add it to the - * dentry cache and continue on to read it from the disk. + * ecryptfs_lookup_and_interpose_lower - Perform a lookup */ -static struct dentry *ecryptfs_lookup(struct inode *dir, struct dentry *dentry, - struct nameidata *nd) +int ecryptfs_lookup_and_interpose_lower(struct dentry *ecryptfs_dentry, + struct dentry *lower_dentry, + struct ecryptfs_crypt_stat *crypt_stat, + struct inode *ecryptfs_dir_inode, + struct nameidata *ecryptfs_nd) { - int rc = 0; struct dentry *lower_dir_dentry; - struct dentry *lower_dentry; struct vfsmount *lower_mnt; - char *encoded_name; - int encoded_namelen; - struct ecryptfs_crypt_stat *crypt_stat = NULL; + struct inode *lower_inode; struct ecryptfs_mount_crypt_stat *mount_crypt_stat; char *page_virt = NULL; - struct inode *lower_inode; u64 file_size; + int rc = 0; - lower_dir_dentry = ecryptfs_dentry_to_lower(dentry->d_parent); - dentry->d_op = &ecryptfs_dops; - if ((dentry->d_name.len == 1 && !strcmp(dentry->d_name.name, ".")) - || (dentry->d_name.len == 2 - && !strcmp(dentry->d_name.name, ".."))) { - d_drop(dentry); - goto out; - } - encoded_namelen = ecryptfs_encode_filename(crypt_stat, - dentry->d_name.name, - dentry->d_name.len, - &encoded_name); - if (encoded_namelen < 0) { - rc = encoded_namelen; - d_drop(dentry); - goto out; - } - ecryptfs_printk(KERN_DEBUG, "encoded_name = [%s]; encoded_namelen " - "= [%d]\n", encoded_name, encoded_namelen); - lower_dentry = lookup_one_len(encoded_name, lower_dir_dentry, - encoded_namelen - 1); - kfree(encoded_name); - if (IS_ERR(lower_dentry)) { - ecryptfs_printk(KERN_ERR, "ERR from lower_dentry\n"); - rc = PTR_ERR(lower_dentry); - d_drop(dentry); - goto out; - } - lower_mnt = mntget(ecryptfs_dentry_to_lower_mnt(dentry->d_parent)); - ecryptfs_printk(KERN_DEBUG, "lower_dentry = [%p]; lower_dentry->" - "d_name.name = [%s]\n", lower_dentry, - lower_dentry->d_name.name); + lower_dir_dentry = lower_dentry->d_parent; + lower_mnt = mntget(ecryptfs_dentry_to_lower_mnt( + ecryptfs_dentry->d_parent)); lower_inode = lower_dentry->d_inode; - fsstack_copy_attr_atime(dir, lower_dir_dentry->d_inode); + fsstack_copy_attr_atime(ecryptfs_dir_inode, lower_dir_dentry->d_inode); BUG_ON(!atomic_read(&lower_dentry->d_count)); - ecryptfs_set_dentry_private(dentry, + ecryptfs_set_dentry_private(ecryptfs_dentry, kmem_cache_alloc(ecryptfs_dentry_info_cache, GFP_KERNEL)); - if (!ecryptfs_dentry_to_private(dentry)) { + if (!ecryptfs_dentry_to_private(ecryptfs_dentry)) { rc = -ENOMEM; - ecryptfs_printk(KERN_ERR, "Out of memory whilst attempting " - "to allocate ecryptfs_dentry_info struct\n"); + printk(KERN_ERR "%s: Out of memory whilst attempting " + "to allocate ecryptfs_dentry_info struct\n", + __func__); goto out_dput; } - ecryptfs_set_dentry_lower(dentry, lower_dentry); - ecryptfs_set_dentry_lower_mnt(dentry, lower_mnt); + ecryptfs_set_dentry_lower(ecryptfs_dentry, lower_dentry); + ecryptfs_set_dentry_lower_mnt(ecryptfs_dentry, lower_mnt); if (!lower_dentry->d_inode) { /* We want to add because we couldn't find in lower */ - d_add(dentry, NULL); + d_add(ecryptfs_dentry, NULL); goto out; } - rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, - ECRYPTFS_INTERPOSE_FLAG_D_ADD); + rc = ecryptfs_interpose(lower_dentry, ecryptfs_dentry, + ecryptfs_dir_inode->i_sb, 1); if (rc) { - ecryptfs_printk(KERN_ERR, "Error interposing\n"); + printk(KERN_ERR "%s: Error interposing; rc = [%d]\n", + __func__, rc); goto out; } - if (S_ISDIR(lower_inode->i_mode)) { - ecryptfs_printk(KERN_DEBUG, "Is a directory; returning\n"); + if (S_ISDIR(lower_inode->i_mode)) goto out; - } - if (S_ISLNK(lower_inode->i_mode)) { - ecryptfs_printk(KERN_DEBUG, "Is a symlink; returning\n"); + if (S_ISLNK(lower_inode->i_mode)) goto out; - } - if (special_file(lower_inode->i_mode)) { - ecryptfs_printk(KERN_DEBUG, "Is a special file; returning\n"); + if (special_file(lower_inode->i_mode)) goto out; - } - if (!nd) { - ecryptfs_printk(KERN_DEBUG, "We have a NULL nd, just leave" - "as we *think* we are about to unlink\n"); + if (!ecryptfs_nd) goto out; - } /* Released in this function */ - page_virt = kmem_cache_zalloc(ecryptfs_header_cache_2, - GFP_USER); + page_virt = kmem_cache_zalloc(ecryptfs_header_cache_2, GFP_USER); if (!page_virt) { + printk(KERN_ERR "%s: Cannot kmem_cache_zalloc() a page\n", + __func__); rc = -ENOMEM; - ecryptfs_printk(KERN_ERR, - "Cannot ecryptfs_kmalloc a page\n"); goto out; } - crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat; - if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)) - ecryptfs_set_default_sizes(crypt_stat); - if (!ecryptfs_inode_to_private(dentry->d_inode)->lower_file) { - rc = ecryptfs_init_persistent_file(dentry); + if (!ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->lower_file) { + rc = ecryptfs_init_persistent_file(ecryptfs_dentry); if (rc) { printk(KERN_ERR "%s: Error attempting to initialize " "the persistent file for the dentry with name " "[%s]; rc = [%d]\n", __func__, - dentry->d_name.name, rc); - goto out; + ecryptfs_dentry->d_name.name, rc); + goto out_free_kmem; } } rc = ecryptfs_read_and_validate_header_region(page_virt, - dentry->d_inode); + ecryptfs_dentry->d_inode); if (rc) { - rc = ecryptfs_read_and_validate_xattr_region(page_virt, dentry); + rc = ecryptfs_read_and_validate_xattr_region(page_virt, + ecryptfs_dentry); if (rc) { - printk(KERN_DEBUG "Valid metadata not found in header " - "region or xattr region; treating file as " - "unencrypted\n"); rc = 0; - kmem_cache_free(ecryptfs_header_cache_2, page_virt); - goto out; + goto out_free_kmem; } crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR; } mount_crypt_stat = &ecryptfs_superblock_to_private( - dentry->d_sb)->mount_crypt_stat; + ecryptfs_dentry->d_sb)->mount_crypt_stat; if (mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED) { if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR) file_size = (crypt_stat->num_header_bytes_at_front @@ -388,14 +337,103 @@ static struct dentry *ecryptfs_lookup(struct inode *dir, struct dentry *dentry, } else { file_size = get_unaligned_be64(page_virt); } - i_size_write(dentry->d_inode, (loff_t)file_size); + i_size_write(ecryptfs_dentry->d_inode, (loff_t)file_size); +out_free_kmem: kmem_cache_free(ecryptfs_header_cache_2, page_virt); goto out; - out_dput: dput(lower_dentry); - d_drop(dentry); + d_drop(ecryptfs_dentry); out: + return rc; +} + +/** + * ecryptfs_lookup + * @ecryptfs_dir_inode: The eCryptfs directory inode + * @ecryptfs_dentry: The eCryptfs dentry that we are looking up + * @ecryptfs_nd: nameidata; may be NULL + * + * Find a file on disk. If the file does not exist, then we'll add it to the + * dentry cache and continue on to read it from the disk. + */ +static struct dentry *ecryptfs_lookup(struct inode *ecryptfs_dir_inode, + struct dentry *ecryptfs_dentry, + struct nameidata *ecryptfs_nd) +{ + char *encrypted_and_encoded_name = NULL; + int encrypted_and_encoded_name_size; + struct ecryptfs_crypt_stat *crypt_stat = NULL; + struct ecryptfs_mount_crypt_stat *mount_crypt_stat = NULL; + struct ecryptfs_inode_info *inode_info; + struct dentry *lower_dir_dentry, *lower_dentry; + int rc = 0; + + ecryptfs_dentry->d_op = &ecryptfs_dops; + if ((ecryptfs_dentry->d_name.len == 1 + && !strcmp(ecryptfs_dentry->d_name.name, ".")) + || (ecryptfs_dentry->d_name.len == 2 + && !strcmp(ecryptfs_dentry->d_name.name, ".."))) { + goto out_d_drop; + } + lower_dir_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry->d_parent); + lower_dentry = lookup_one_len(ecryptfs_dentry->d_name.name, + lower_dir_dentry, + ecryptfs_dentry->d_name.len); + if (IS_ERR(lower_dentry)) { + rc = PTR_ERR(lower_dentry); + printk(KERN_ERR "%s: lookup_one_len() returned [%d] on " + "lower_dentry = [%s]\n", __func__, rc, + ecryptfs_dentry->d_name.name); + goto out_d_drop; + } + if (lower_dentry->d_inode) + goto lookup_and_interpose; + inode_info = ecryptfs_inode_to_private(ecryptfs_dentry->d_inode); + if (inode_info) { + crypt_stat = &inode_info->crypt_stat; + /* TODO: lock for crypt_stat comparison */ + if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)) + ecryptfs_set_default_sizes(crypt_stat); + } + if (crypt_stat) + mount_crypt_stat = crypt_stat->mount_crypt_stat; + else + mount_crypt_stat = &ecryptfs_superblock_to_private( + ecryptfs_dentry->d_sb)->mount_crypt_stat; + if (!(crypt_stat && (crypt_stat->flags & ECRYPTFS_ENCRYPT_FILENAMES)) + && !(mount_crypt_stat && (mount_crypt_stat->flags + & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES))) + goto lookup_and_interpose; + dput(lower_dentry); + rc = ecryptfs_encrypt_and_encode_filename( + &encrypted_and_encoded_name, &encrypted_and_encoded_name_size, + crypt_stat, mount_crypt_stat, ecryptfs_dentry->d_name.name, + ecryptfs_dentry->d_name.len); + if (rc) { + printk(KERN_ERR "%s: Error attempting to encrypt and encode " + "filename; rc = [%d]\n", __func__, rc); + goto out_d_drop; + } + lower_dentry = lookup_one_len(encrypted_and_encoded_name, + lower_dir_dentry, + encrypted_and_encoded_name_size - 1); + if (IS_ERR(lower_dentry)) { + rc = PTR_ERR(lower_dentry); + printk(KERN_ERR "%s: lookup_one_len() returned [%d] on " + "lower_dentry = [%s]\n", __func__, rc, + encrypted_and_encoded_name); + goto out_d_drop; + } +lookup_and_interpose: + rc = ecryptfs_lookup_and_interpose_lower(ecryptfs_dentry, lower_dentry, + crypt_stat, ecryptfs_dir_inode, + ecryptfs_nd); + goto out; +out_d_drop: + d_drop(ecryptfs_dentry); +out: + kfree(encrypted_and_encoded_name); return ERR_PTR(rc); } @@ -466,19 +504,21 @@ static int ecryptfs_symlink(struct inode *dir, struct dentry *dentry, struct dentry *lower_dentry; struct dentry *lower_dir_dentry; char *encoded_symname; - int encoded_symlen; - struct ecryptfs_crypt_stat *crypt_stat = NULL; + size_t encoded_symlen; + struct ecryptfs_mount_crypt_stat *mount_crypt_stat = NULL; lower_dentry = ecryptfs_dentry_to_lower(dentry); dget(lower_dentry); lower_dir_dentry = lock_parent(lower_dentry); - encoded_symlen = ecryptfs_encode_filename(crypt_stat, symname, - strlen(symname), - &encoded_symname); - if (encoded_symlen < 0) { - rc = encoded_symlen; + mount_crypt_stat = &ecryptfs_superblock_to_private( + dir->i_sb)->mount_crypt_stat; + rc = ecryptfs_encrypt_and_encode_filename(&encoded_symname, + &encoded_symlen, + NULL, + mount_crypt_stat, symname, + strlen(symname)); + if (rc) goto out_lock; - } rc = vfs_symlink(lower_dir_dentry->d_inode, lower_dentry, encoded_symname); kfree(encoded_symname); @@ -602,14 +642,15 @@ out_lock: } static int -ecryptfs_readlink(struct dentry *dentry, char __user * buf, int bufsiz) +ecryptfs_readlink(struct dentry *dentry, char __user *buf, int bufsiz) { - int rc; - struct dentry *lower_dentry; - char *decoded_name; char *lower_buf; - mm_segment_t old_fs; + struct dentry *lower_dentry; struct ecryptfs_crypt_stat *crypt_stat; + char *plaintext_name; + size_t plaintext_name_size; + mm_segment_t old_fs; + int rc; lower_dentry = ecryptfs_dentry_to_lower(dentry); if (!lower_dentry->d_inode->i_op || @@ -617,38 +658,39 @@ ecryptfs_readlink(struct dentry *dentry, char __user * buf, int bufsiz) rc = -EINVAL; goto out; } + crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat; /* Released in this function */ lower_buf = kmalloc(bufsiz, GFP_KERNEL); if (lower_buf == NULL) { - ecryptfs_printk(KERN_ERR, "Out of memory\n"); + printk(KERN_ERR "%s: Out of memory whilst attempting to " + "kmalloc [%d] bytes\n", __func__, bufsiz); rc = -ENOMEM; goto out; } old_fs = get_fs(); set_fs(get_ds()); - ecryptfs_printk(KERN_DEBUG, "Calling readlink w/ " - "lower_dentry->d_name.name = [%s]\n", - lower_dentry->d_name.name); rc = lower_dentry->d_inode->i_op->readlink(lower_dentry, (char __user *)lower_buf, bufsiz); set_fs(old_fs); if (rc >= 0) { - crypt_stat = NULL; - rc = ecryptfs_decode_filename(crypt_stat, lower_buf, rc, - &decoded_name); - if (rc == -ENOMEM) + rc = ecryptfs_decode_and_decrypt_filename(&plaintext_name, + &plaintext_name_size, + dentry, lower_buf, + rc); + if (rc) { + printk(KERN_ERR "%s: Error attempting to decode and " + "decrypt filename; rc = [%d]\n", __func__, + rc); goto out_free_lower_buf; - if (rc > 0) { - ecryptfs_printk(KERN_DEBUG, "Copying [%d] bytes " - "to userspace: [%*s]\n", rc, - decoded_name); - if (copy_to_user(buf, decoded_name, rc)) - rc = -EFAULT; } - kfree(decoded_name); - fsstack_copy_attr_atime(dentry->d_inode, - lower_dentry->d_inode); + rc = copy_to_user(buf, plaintext_name, plaintext_name_size); + if (rc) + rc = -EFAULT; + else + rc = plaintext_name_size; + kfree(plaintext_name); + fsstack_copy_attr_atime(dentry->d_inode, lower_dentry->d_inode); } out_free_lower_buf: kfree(lower_buf); @@ -670,8 +712,6 @@ static void *ecryptfs_follow_link(struct dentry *dentry, struct nameidata *nd) } old_fs = get_fs(); set_fs(get_ds()); - ecryptfs_printk(KERN_DEBUG, "Calling readlink w/ " - "dentry->d_name.name = [%s]\n", dentry->d_name.name); rc = dentry->d_inode->i_op->readlink(dentry, (char __user *)buf, len); buf[rc] = '\0'; set_fs(old_fs); -- 1.5.3.6 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/