From 0216f7f7921759211e48e8b940eae29f0fe43902 Mon Sep 17 00:00:00 2001 From: Michael Halcrow Date: Tue, 16 Oct 2007 01:28:08 -0700 Subject: eCryptfs: replace encrypt, decrypt, and inode size write Replace page encryption and decryption routines and inode size write routine with versions that utilize the read_write.c functions. Signed-off-by: Michael Halcrow Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/ecryptfs/mmap.c | 131 +++++++++++++++++------------------------------------ 1 file changed, 41 insertions(+), 90 deletions(-) (limited to 'fs/ecryptfs/mmap.c') diff --git a/fs/ecryptfs/mmap.c b/fs/ecryptfs/mmap.c index 0c53320b9eb..9b621108d5c 100644 --- a/fs/ecryptfs/mmap.c +++ b/fs/ecryptfs/mmap.c @@ -171,13 +171,9 @@ out: */ static int ecryptfs_writepage(struct page *page, struct writeback_control *wbc) { - struct ecryptfs_page_crypt_context ctx; int rc; - ctx.page = page; - ctx.mode = ECRYPTFS_WRITEPAGE_MODE; - ctx.param.wbc = wbc; - rc = ecryptfs_encrypt_page(&ctx); + rc = ecryptfs_encrypt_page(page); if (rc) { ecryptfs_printk(KERN_WARNING, "Error encrypting " "page (upper index [0x%.16x])\n", page->index); @@ -341,7 +337,7 @@ static int ecryptfs_readpage(struct file *file, struct page *page) } } } else { - rc = ecryptfs_decrypt_page(file, page); + rc = ecryptfs_decrypt_page(page); if (rc) { ecryptfs_printk(KERN_ERR, "Error decrypting page; " "rc = [%d]\n", rc); @@ -459,58 +455,48 @@ static void ecryptfs_release_lower_page(struct page *lower_page) * * Returns zero on success; non-zero on error. */ -static int ecryptfs_write_inode_size_to_header(struct file *lower_file, - struct inode *lower_inode, - struct inode *inode) +static int ecryptfs_write_inode_size_to_header(struct inode *ecryptfs_inode) { - int rc = 0; - struct page *header_page; - char *header_virt; - const struct address_space_operations *lower_a_ops; u64 file_size; + char *file_size_virt; + int rc; - header_page = grab_cache_page(lower_inode->i_mapping, 0); - if (!header_page) { - ecryptfs_printk(KERN_ERR, "grab_cache_page for " - "lower_page_index 0 failed\n"); - rc = -EINVAL; - goto out; - } - lower_a_ops = lower_inode->i_mapping->a_ops; - rc = lower_a_ops->prepare_write(lower_file, header_page, 0, 8); - if (rc) { - ecryptfs_release_lower_page(header_page); + file_size_virt = kmalloc(sizeof(u64), GFP_KERNEL); + if (!file_size_virt) { + rc = -ENOMEM; goto out; } - file_size = (u64)i_size_read(inode); - ecryptfs_printk(KERN_DEBUG, "Writing size: [0x%.16x]\n", file_size); + file_size = (u64)i_size_read(ecryptfs_inode); file_size = cpu_to_be64(file_size); - header_virt = kmap_atomic(header_page, KM_USER0); - memcpy(header_virt, &file_size, sizeof(u64)); - kunmap_atomic(header_virt, KM_USER0); - flush_dcache_page(header_page); - rc = lower_a_ops->commit_write(lower_file, header_page, 0, 8); - if (rc < 0) - ecryptfs_printk(KERN_ERR, "Error commiting header page " - "write\n"); - ecryptfs_release_lower_page(header_page); - lower_inode->i_mtime = lower_inode->i_ctime = CURRENT_TIME; - mark_inode_dirty_sync(inode); + memcpy(file_size_virt, &file_size, sizeof(u64)); + rc = ecryptfs_write_lower(ecryptfs_inode, file_size_virt, 0, + sizeof(u64)); + kfree(file_size_virt); + if (rc) + printk(KERN_ERR "%s: Error writing file size to header; " + "rc = [%d]\n", __FUNCTION__, rc); out: return rc; } -static int ecryptfs_write_inode_size_to_xattr(struct inode *lower_inode, - struct inode *inode, - struct dentry *ecryptfs_dentry, - int lower_i_mutex_held) +struct kmem_cache *ecryptfs_xattr_cache; + +static int ecryptfs_write_inode_size_to_xattr(struct inode *ecryptfs_inode) { ssize_t size; void *xattr_virt; - struct dentry *lower_dentry; + struct dentry *lower_dentry = + ecryptfs_inode_to_private(ecryptfs_inode)->lower_file->f_dentry; + struct inode *lower_inode = lower_dentry->d_inode; u64 file_size; int rc; + if (!lower_inode->i_op->getxattr || !lower_inode->i_op->setxattr) { + printk(KERN_WARNING + "No support for setting xattr in lower filesystem\n"); + rc = -ENOSYS; + goto out; + } xattr_virt = kmem_cache_alloc(ecryptfs_xattr_cache, GFP_KERNEL); if (!xattr_virt) { printk(KERN_ERR "Out of memory whilst attempting to write " @@ -518,35 +504,17 @@ static int ecryptfs_write_inode_size_to_xattr(struct inode *lower_inode, rc = -ENOMEM; goto out; } - lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry); - if (!lower_dentry->d_inode->i_op->getxattr || - !lower_dentry->d_inode->i_op->setxattr) { - printk(KERN_WARNING - "No support for setting xattr in lower filesystem\n"); - rc = -ENOSYS; - kmem_cache_free(ecryptfs_xattr_cache, xattr_virt); - goto out; - } - if (!lower_i_mutex_held) - mutex_lock(&lower_dentry->d_inode->i_mutex); - size = lower_dentry->d_inode->i_op->getxattr(lower_dentry, - ECRYPTFS_XATTR_NAME, - xattr_virt, - PAGE_CACHE_SIZE); - if (!lower_i_mutex_held) - mutex_unlock(&lower_dentry->d_inode->i_mutex); + mutex_lock(&lower_inode->i_mutex); + size = lower_inode->i_op->getxattr(lower_dentry, ECRYPTFS_XATTR_NAME, + xattr_virt, PAGE_CACHE_SIZE); if (size < 0) size = 8; - file_size = (u64)i_size_read(inode); + file_size = (u64)i_size_read(ecryptfs_inode); file_size = cpu_to_be64(file_size); memcpy(xattr_virt, &file_size, sizeof(u64)); - if (!lower_i_mutex_held) - mutex_lock(&lower_dentry->d_inode->i_mutex); - rc = lower_dentry->d_inode->i_op->setxattr(lower_dentry, - ECRYPTFS_XATTR_NAME, - xattr_virt, size, 0); - if (!lower_i_mutex_held) - mutex_unlock(&lower_dentry->d_inode->i_mutex); + rc = lower_inode->i_op->setxattr(lower_dentry, ECRYPTFS_XATTR_NAME, + xattr_virt, size, 0); + mutex_unlock(&lower_inode->i_mutex); if (rc) printk(KERN_ERR "Error whilst attempting to write inode size " "to lower file xattr; rc = [%d]\n", rc); @@ -555,24 +523,15 @@ out: return rc; } -int -ecryptfs_write_inode_size_to_metadata(struct file *lower_file, - struct inode *lower_inode, - struct inode *inode, - struct dentry *ecryptfs_dentry, - int lower_i_mutex_held) +int ecryptfs_write_inode_size_to_metadata(struct inode *ecryptfs_inode) { struct ecryptfs_crypt_stat *crypt_stat; - crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat; + crypt_stat = &ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat; if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR) - return ecryptfs_write_inode_size_to_xattr(lower_inode, inode, - ecryptfs_dentry, - lower_i_mutex_held); + return ecryptfs_write_inode_size_to_xattr(ecryptfs_inode); else - return ecryptfs_write_inode_size_to_header(lower_file, - lower_inode, - inode); + return ecryptfs_write_inode_size_to_header(ecryptfs_inode); } int ecryptfs_get_lower_page(struct page **lower_page, struct inode *lower_inode, @@ -659,8 +618,6 @@ out: return rc; } -struct kmem_cache *ecryptfs_xattr_cache; - /** * ecryptfs_commit_write * @file: The eCryptfs file object @@ -675,7 +632,6 @@ struct kmem_cache *ecryptfs_xattr_cache; static int ecryptfs_commit_write(struct file *file, struct page *page, unsigned from, unsigned to) { - struct ecryptfs_page_crypt_context ctx; loff_t pos; struct inode *inode; struct inode *lower_inode; @@ -705,10 +661,7 @@ static int ecryptfs_commit_write(struct file *file, struct page *page, page->index); goto out; } - ctx.page = page; - ctx.mode = ECRYPTFS_PREPARE_COMMIT_MODE; - ctx.param.lower_file = lower_file; - rc = ecryptfs_encrypt_page(&ctx); + rc = ecryptfs_encrypt_page(page); if (rc) { ecryptfs_printk(KERN_WARNING, "Error encrypting page (upper " "index [0x%.16x])\n", page->index); @@ -721,9 +674,7 @@ static int ecryptfs_commit_write(struct file *file, struct page *page, ecryptfs_printk(KERN_DEBUG, "Expanded file size to " "[0x%.16x]\n", i_size_read(inode)); } - rc = ecryptfs_write_inode_size_to_metadata(lower_file, lower_inode, - inode, file->f_dentry, - ECRYPTFS_LOWER_I_MUTEX_HELD); + rc = ecryptfs_write_inode_size_to_metadata(inode); if (rc) printk(KERN_ERR "Error writing inode size to metadata; " "rc = [%d]\n", rc); -- cgit