--- /dev/null
-#include <linux/crypto.h>
-#include <linux/ecryptfs.h>
+ /*
+ * This contains encryption functions for per-file encryption.
+ *
+ * Copyright (C) 2015, Google, Inc.
+ * Copyright (C) 2015, Motorola Mobility
+ *
+ * Written by Michael Halcrow, 2014.
+ *
+ * Filename encryption additions
+ * Uday Savagaonkar, 2014
+ * Encryption policy handling additions
+ * Ildar Muslukhov, 2014
+ * Add fscrypt_pullback_bio_page()
+ * Jaegeuk Kim, 2015.
+ *
+ * This has not yet undergone a rigorous security audit.
+ *
+ * The usage of AES-XTS should conform to recommendations in NIST
+ * Special Publication 800-38E and IEEE P1619/D16.
+ */
+
- struct ablkcipher_request *req = NULL;
+ #include <linux/pagemap.h>
+ #include <linux/mempool.h>
+ #include <linux/module.h>
+ #include <linux/scatterlist.h>
+ #include <linux/ratelimit.h>
+ #include <linux/bio.h>
+ #include <linux/dcache.h>
+ #include <linux/fscrypto.h>
++#include <linux/ecryptfs.h>
+
+ static unsigned int num_prealloc_crypto_pages = 32;
+ static unsigned int num_prealloc_crypto_ctxs = 128;
+
+ module_param(num_prealloc_crypto_pages, uint, 0444);
+ MODULE_PARM_DESC(num_prealloc_crypto_pages,
+ "Number of crypto pages to preallocate");
+ module_param(num_prealloc_crypto_ctxs, uint, 0444);
+ MODULE_PARM_DESC(num_prealloc_crypto_ctxs,
+ "Number of crypto contexts to preallocate");
+
+ static mempool_t *fscrypt_bounce_page_pool = NULL;
+
+ static LIST_HEAD(fscrypt_free_ctxs);
+ static DEFINE_SPINLOCK(fscrypt_ctx_lock);
+
+ static struct workqueue_struct *fscrypt_read_workqueue;
+ static DEFINE_MUTEX(fscrypt_init_mutex);
+
+ static struct kmem_cache *fscrypt_ctx_cachep;
+ struct kmem_cache *fscrypt_info_cachep;
+
+ /**
+ * fscrypt_release_ctx() - Releases an encryption context
+ * @ctx: The encryption context to release.
+ *
+ * If the encryption context was allocated from the pre-allocated pool, returns
+ * it to that pool. Else, frees it.
+ *
+ * If there's a bounce page in the context, this frees that.
+ */
+ void fscrypt_release_ctx(struct fscrypt_ctx *ctx)
+ {
+ unsigned long flags;
+
+ if (ctx->flags & FS_WRITE_PATH_FL && ctx->w.bounce_page) {
+ mempool_free(ctx->w.bounce_page, fscrypt_bounce_page_pool);
+ ctx->w.bounce_page = NULL;
+ }
+ ctx->w.control_page = NULL;
+ if (ctx->flags & FS_CTX_REQUIRES_FREE_ENCRYPT_FL) {
+ kmem_cache_free(fscrypt_ctx_cachep, ctx);
+ } else {
+ spin_lock_irqsave(&fscrypt_ctx_lock, flags);
+ list_add(&ctx->free_list, &fscrypt_free_ctxs);
+ spin_unlock_irqrestore(&fscrypt_ctx_lock, flags);
+ }
+ }
+ EXPORT_SYMBOL(fscrypt_release_ctx);
+
+ /**
+ * fscrypt_get_ctx() - Gets an encryption context
+ * @inode: The inode for which we are doing the crypto
+ *
+ * Allocates and initializes an encryption context.
+ *
+ * Return: An allocated and initialized encryption context on success; error
+ * value or NULL otherwise.
+ */
+ struct fscrypt_ctx *fscrypt_get_ctx(struct inode *inode)
+ {
+ struct fscrypt_ctx *ctx = NULL;
+ struct fscrypt_info *ci = inode->i_crypt_info;
+ unsigned long flags;
+
+ if (ci == NULL)
+ return ERR_PTR(-ENOKEY);
+
+ /*
+ * We first try getting the ctx from a free list because in
+ * the common case the ctx will have an allocated and
+ * initialized crypto tfm, so it's probably a worthwhile
+ * optimization. For the bounce page, we first try getting it
+ * from the kernel allocator because that's just about as fast
+ * as getting it from a list and because a cache of free pages
+ * should generally be a "last resort" option for a filesystem
+ * to be able to do its job.
+ */
+ spin_lock_irqsave(&fscrypt_ctx_lock, flags);
+ ctx = list_first_entry_or_null(&fscrypt_free_ctxs,
+ struct fscrypt_ctx, free_list);
+ if (ctx)
+ list_del(&ctx->free_list);
+ spin_unlock_irqrestore(&fscrypt_ctx_lock, flags);
+ if (!ctx) {
+ ctx = kmem_cache_zalloc(fscrypt_ctx_cachep, GFP_NOFS);
+ if (!ctx)
+ return ERR_PTR(-ENOMEM);
+ ctx->flags |= FS_CTX_REQUIRES_FREE_ENCRYPT_FL;
+ } else {
+ ctx->flags &= ~FS_CTX_REQUIRES_FREE_ENCRYPT_FL;
+ }
+ ctx->flags &= ~FS_WRITE_PATH_FL;
+ return ctx;
+ }
+ EXPORT_SYMBOL(fscrypt_get_ctx);
+
+ /**
+ * fscrypt_complete() - The completion callback for page encryption
+ * @req: The asynchronous encryption request context
+ * @res: The result of the encryption operation
+ */
+ static void fscrypt_complete(struct crypto_async_request *req, int res)
+ {
+ struct fscrypt_completion_result *ecr = req->data;
+
+ if (res == -EINPROGRESS)
+ return;
+ ecr->res = res;
+ complete(&ecr->completion);
+ }
+
+ typedef enum {
+ FS_DECRYPT = 0,
+ FS_ENCRYPT,
+ } fscrypt_direction_t;
+
+ static int do_page_crypto(struct inode *inode,
+ fscrypt_direction_t rw, pgoff_t index,
+ struct page *src_page, struct page *dest_page)
+ {
+ u8 xts_tweak[FS_XTS_TWEAK_SIZE];
- struct crypto_ablkcipher *tfm = ci->ci_ctfm;
++ struct skcipher_request *req = NULL;
+ DECLARE_FS_COMPLETION_RESULT(ecr);
+ struct scatterlist dst, src;
+ struct fscrypt_info *ci = inode->i_crypt_info;
- req = ablkcipher_request_alloc(tfm, GFP_NOFS);
++ struct crypto_skcipher *tfm = ci->ci_ctfm;
+ int res = 0;
+
- ablkcipher_request_set_callback(
++ req = skcipher_request_alloc(tfm, GFP_NOFS);
+ if (!req) {
+ printk_ratelimited(KERN_ERR
+ "%s: crypto_request_alloc() failed\n",
+ __func__);
+ return -ENOMEM;
+ }
+
- ablkcipher_request_set_crypt(req, &src, &dst, PAGE_CACHE_SIZE,
++ skcipher_request_set_callback(
+ req, CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
+ fscrypt_complete, &ecr);
+
+ BUILD_BUG_ON(FS_XTS_TWEAK_SIZE < sizeof(index));
+ memcpy(xts_tweak, &inode->i_ino, sizeof(index));
+ memset(&xts_tweak[sizeof(index)], 0,
+ FS_XTS_TWEAK_SIZE - sizeof(index));
+
+ sg_init_table(&dst, 1);
+ sg_set_page(&dst, dest_page, PAGE_CACHE_SIZE, 0);
+ sg_init_table(&src, 1);
+ sg_set_page(&src, src_page, PAGE_CACHE_SIZE, 0);
- res = crypto_ablkcipher_decrypt(req);
++ skcipher_request_set_crypt(req, &src, &dst, PAGE_CACHE_SIZE,
+ xts_tweak);
+ if (rw == FS_DECRYPT)
- res = crypto_ablkcipher_encrypt(req);
++ res = crypto_skcipher_decrypt(req);
+ else
- ablkcipher_request_free(req);
++ res = crypto_skcipher_encrypt(req);
+ if (res == -EINPROGRESS || res == -EBUSY) {
+ BUG_ON(req->base.data != &ecr);
+ wait_for_completion(&ecr.completion);
+ res = ecr.res;
+ }
- "%s: crypto_ablkcipher_encrypt() returned %d\n",
++ skcipher_request_free(req);
+ if (res) {
+ printk_ratelimited(KERN_ERR
++ "%s: crypto_skcipher_encrypt() returned %d\n",
+ __func__, res);
+ return res;
+ }
+ return 0;
+ }
+
+ static struct page *alloc_bounce_page(struct fscrypt_ctx *ctx)
+ {
+ ctx->w.bounce_page = mempool_alloc(fscrypt_bounce_page_pool,
+ GFP_NOWAIT);
+ if (ctx->w.bounce_page == NULL)
+ return ERR_PTR(-ENOMEM);
+ ctx->flags |= FS_WRITE_PATH_FL;
+ return ctx->w.bounce_page;
+ }
+
+ /**
+ * fscypt_encrypt_page() - Encrypts a page
+ * @inode: The inode for which the encryption should take place
+ * @plaintext_page: The page to encrypt. Must be locked.
+ *
+ * Allocates a ciphertext page and encrypts plaintext_page into it using the ctx
+ * encryption context.
+ *
+ * Called on the page write path. The caller must call
+ * fscrypt_restore_control_page() on the returned ciphertext page to
+ * release the bounce buffer and the encryption context.
+ *
+ * Return: An allocated page with the encrypted content on success. Else, an
+ * error value or NULL.
+ */
+ struct page *fscrypt_encrypt_page(struct inode *inode,
+ struct page *plaintext_page)
+ {
+ struct fscrypt_ctx *ctx;
+ struct page *ciphertext_page = NULL;
+ int err;
+
+ BUG_ON(!PageLocked(plaintext_page));
+
+ ctx = fscrypt_get_ctx(inode);
+ if (IS_ERR(ctx))
+ return (struct page *)ctx;
+
+ /* The encryption operation will require a bounce page. */
+ ciphertext_page = alloc_bounce_page(ctx);
+ if (IS_ERR(ciphertext_page))
+ goto errout;
+
+ ctx->w.control_page = plaintext_page;
+ err = do_page_crypto(inode, FS_ENCRYPT, plaintext_page->index,
+ plaintext_page, ciphertext_page);
+ if (err) {
+ ciphertext_page = ERR_PTR(err);
+ goto errout;
+ }
+ SetPagePrivate(ciphertext_page);
+ set_page_private(ciphertext_page, (unsigned long)ctx);
+ lock_page(ciphertext_page);
+ return ciphertext_page;
+
+ errout:
+ fscrypt_release_ctx(ctx);
+ return ciphertext_page;
+ }
+ EXPORT_SYMBOL(fscrypt_encrypt_page);
+
+ /**
+ * f2crypt_decrypt_page() - Decrypts a page in-place
+ * @page: The page to decrypt. Must be locked.
+ *
+ * Decrypts page in-place using the ctx encryption context.
+ *
+ * Called from the read completion callback.
+ *
+ * Return: Zero on success, non-zero otherwise.
+ */
+ int fscrypt_decrypt_page(struct page *page)
+ {
+ BUG_ON(!PageLocked(page));
+
+ return do_page_crypto(page->mapping->host,
+ FS_DECRYPT, page->index, page, page);
+ }
+ EXPORT_SYMBOL(fscrypt_decrypt_page);
+
+ int fscrypt_zeroout_range(struct inode *inode, pgoff_t lblk,
+ sector_t pblk, unsigned int len)
+ {
+ struct fscrypt_ctx *ctx;
+ struct page *ciphertext_page = NULL;
+ struct bio *bio;
+ int ret, err = 0;
+
+ BUG_ON(inode->i_sb->s_blocksize != PAGE_CACHE_SIZE);
+
+ ctx = fscrypt_get_ctx(inode);
+ if (IS_ERR(ctx))
+ return PTR_ERR(ctx);
+
+ ciphertext_page = alloc_bounce_page(ctx);
+ if (IS_ERR(ciphertext_page)) {
+ err = PTR_ERR(ciphertext_page);
+ goto errout;
+ }
+
+ while (len--) {
+ err = do_page_crypto(inode, FS_ENCRYPT, lblk,
+ ZERO_PAGE(0), ciphertext_page);
+ if (err)
+ goto errout;
+
+ bio = bio_alloc(GFP_KERNEL, 1);
+ if (!bio) {
+ err = -ENOMEM;
+ goto errout;
+ }
+ bio->bi_bdev = inode->i_sb->s_bdev;
+ bio->bi_iter.bi_sector =
+ pblk << (inode->i_sb->s_blocksize_bits - 9);
+ ret = bio_add_page(bio, ciphertext_page,
+ inode->i_sb->s_blocksize, 0);
+ if (ret != inode->i_sb->s_blocksize) {
+ /* should never happen! */
+ WARN_ON(1);
+ bio_put(bio);
+ err = -EIO;
+ goto errout;
+ }
+ err = submit_bio_wait(WRITE, bio);
+ if ((err == 0) && bio->bi_error)
+ err = -EIO;
+ bio_put(bio);
+ if (err)
+ goto errout;
+ lblk++;
+ pblk++;
+ }
+ err = 0;
+ errout:
+ fscrypt_release_ctx(ctx);
+ return err;
+ }
+ EXPORT_SYMBOL(fscrypt_zeroout_range);
+
+ /*
+ * Validate dentries for encrypted directories to make sure we aren't
+ * potentially caching stale data after a key has been added or
+ * removed.
+ */
+ static int fscrypt_d_revalidate(struct dentry *dentry, unsigned int flags)
+ {
+ struct inode *dir = d_inode(dentry->d_parent);
+ struct fscrypt_info *ci = dir->i_crypt_info;
+ int dir_has_key, cached_with_key;
+
+ if (!dir->i_sb->s_cop->is_encrypted(dir))
+ return 0;
+
+ if (ci && ci->ci_keyring_key &&
+ (ci->ci_keyring_key->flags & ((1 << KEY_FLAG_INVALIDATED) |
+ (1 << KEY_FLAG_REVOKED) |
+ (1 << KEY_FLAG_DEAD))))
+ ci = NULL;
+
+ /* this should eventually be an flag in d_flags */
+ spin_lock(&dentry->d_lock);
+ cached_with_key = dentry->d_flags & DCACHE_ENCRYPTED_WITH_KEY;
+ spin_unlock(&dentry->d_lock);
+ dir_has_key = (ci != NULL);
+
+ /*
+ * If the dentry was cached without the key, and it is a
+ * negative dentry, it might be a valid name. We can't check
+ * if the key has since been made available due to locking
+ * reasons, so we fail the validation so ext4_lookup() can do
+ * this check.
+ *
+ * We also fail the validation if the dentry was created with
+ * the key present, but we no longer have the key, or vice versa.
+ */
+ if ((!cached_with_key && d_is_negative(dentry)) ||
+ (!cached_with_key && dir_has_key) ||
+ (cached_with_key && !dir_has_key))
+ return 0;
+ return 1;
+ }
+
+ const struct dentry_operations fscrypt_d_ops = {
+ .d_revalidate = fscrypt_d_revalidate,
+ };
+ EXPORT_SYMBOL(fscrypt_d_ops);
+
+ /*
+ * Call fscrypt_decrypt_page on every single page, reusing the encryption
+ * context.
+ */
+ static void completion_pages(struct work_struct *work)
+ {
+ struct fscrypt_ctx *ctx =
+ container_of(work, struct fscrypt_ctx, r.work);
+ struct bio *bio = ctx->r.bio;
+ struct bio_vec *bv;
+ int i;
+
+ bio_for_each_segment_all(bv, bio, i) {
+ struct page *page = bv->bv_page;
+ int ret = fscrypt_decrypt_page(page);
+
+ if (ret) {
+ WARN_ON_ONCE(1);
+ SetPageError(page);
+ } else {
+ SetPageUptodate(page);
+ }
+ unlock_page(page);
+ }
+ fscrypt_release_ctx(ctx);
+ bio_put(bio);
+ }
+
+ void fscrypt_decrypt_bio_pages(struct fscrypt_ctx *ctx, struct bio *bio)
+ {
+ INIT_WORK(&ctx->r.work, completion_pages);
+ ctx->r.bio = bio;
+ queue_work(fscrypt_read_workqueue, &ctx->r.work);
+ }
+ EXPORT_SYMBOL(fscrypt_decrypt_bio_pages);
+
+ void fscrypt_pullback_bio_page(struct page **page, bool restore)
+ {
+ struct fscrypt_ctx *ctx;
+ struct page *bounce_page;
+
+ /* The bounce data pages are unmapped. */
+ if ((*page)->mapping)
+ return;
+
+ /* The bounce data page is unmapped. */
+ bounce_page = *page;
+ ctx = (struct fscrypt_ctx *)page_private(bounce_page);
+
+ /* restore control page */
+ *page = ctx->w.control_page;
+
+ if (restore)
+ fscrypt_restore_control_page(bounce_page);
+ }
+ EXPORT_SYMBOL(fscrypt_pullback_bio_page);
+
+ void fscrypt_restore_control_page(struct page *page)
+ {
+ struct fscrypt_ctx *ctx;
+
+ ctx = (struct fscrypt_ctx *)page_private(page);
+ set_page_private(page, (unsigned long)NULL);
+ ClearPagePrivate(page);
+ unlock_page(page);
+ fscrypt_release_ctx(ctx);
+ }
+ EXPORT_SYMBOL(fscrypt_restore_control_page);
+
+ static void fscrypt_destroy(void)
+ {
+ struct fscrypt_ctx *pos, *n;
+
+ list_for_each_entry_safe(pos, n, &fscrypt_free_ctxs, free_list)
+ kmem_cache_free(fscrypt_ctx_cachep, pos);
+ INIT_LIST_HEAD(&fscrypt_free_ctxs);
+ mempool_destroy(fscrypt_bounce_page_pool);
+ fscrypt_bounce_page_pool = NULL;
+ }
+
+ /**
+ * fscrypt_initialize() - allocate major buffers for fs encryption.
+ *
+ * We only call this when we start accessing encrypted files, since it
+ * results in memory getting allocated that wouldn't otherwise be used.
+ *
+ * Return: Zero on success, non-zero otherwise.
+ */
+ int fscrypt_initialize(void)
+ {
+ int i, res = -ENOMEM;
+
+ if (fscrypt_bounce_page_pool)
+ return 0;
+
+ mutex_lock(&fscrypt_init_mutex);
+ if (fscrypt_bounce_page_pool)
+ goto already_initialized;
+
+ for (i = 0; i < num_prealloc_crypto_ctxs; i++) {
+ struct fscrypt_ctx *ctx;
+
+ ctx = kmem_cache_zalloc(fscrypt_ctx_cachep, GFP_NOFS);
+ if (!ctx)
+ goto fail;
+ list_add(&ctx->free_list, &fscrypt_free_ctxs);
+ }
+
+ fscrypt_bounce_page_pool =
+ mempool_create_page_pool(num_prealloc_crypto_pages, 0);
+ if (!fscrypt_bounce_page_pool)
+ goto fail;
+
+ already_initialized:
+ mutex_unlock(&fscrypt_init_mutex);
+ return 0;
+ fail:
+ fscrypt_destroy();
+ mutex_unlock(&fscrypt_init_mutex);
+ return res;
+ }
+ EXPORT_SYMBOL(fscrypt_initialize);
+
+ /**
+ * fscrypt_init() - Set up for fs encryption.
+ */
+ static int __init fscrypt_init(void)
+ {
+ fscrypt_read_workqueue = alloc_workqueue("fscrypt_read_queue",
+ WQ_HIGHPRI, 0);
+ if (!fscrypt_read_workqueue)
+ goto fail;
+
+ fscrypt_ctx_cachep = KMEM_CACHE(fscrypt_ctx, SLAB_RECLAIM_ACCOUNT);
+ if (!fscrypt_ctx_cachep)
+ goto fail_free_queue;
+
+ fscrypt_info_cachep = KMEM_CACHE(fscrypt_info, SLAB_RECLAIM_ACCOUNT);
+ if (!fscrypt_info_cachep)
+ goto fail_free_ctx;
+
+ return 0;
+
+ fail_free_ctx:
+ kmem_cache_destroy(fscrypt_ctx_cachep);
+ fail_free_queue:
+ destroy_workqueue(fscrypt_read_workqueue);
+ fail:
+ return -ENOMEM;
+ }
+ module_init(fscrypt_init)
+
+ /**
+ * fscrypt_exit() - Shutdown the fs encryption system
+ */
+ static void __exit fscrypt_exit(void)
+ {
+ fscrypt_destroy();
+
+ if (fscrypt_read_workqueue)
+ destroy_workqueue(fscrypt_read_workqueue);
+ kmem_cache_destroy(fscrypt_ctx_cachep);
+ kmem_cache_destroy(fscrypt_info_cachep);
+ }
+ module_exit(fscrypt_exit);
+
+ MODULE_LICENSE("GPL");
--- /dev/null
-#include <crypto/hash.h>
-#include <crypto/sha.h>
+ /*
+ * This contains functions for filename crypto management
+ *
+ * Copyright (C) 2015, Google, Inc.
+ * Copyright (C) 2015, Motorola Mobility
+ *
+ * Written by Uday Savagaonkar, 2014.
+ * Modified by Jaegeuk Kim, 2015.
+ *
+ * This has not yet undergone a rigorous security audit.
+ */
+
-#include <linux/crypto.h>
+ #include <keys/encrypted-type.h>
+ #include <keys/user-type.h>
- struct ablkcipher_request *req = NULL;
+ #include <linux/scatterlist.h>
+ #include <linux/ratelimit.h>
+ #include <linux/fscrypto.h>
+
+ static u32 size_round_up(size_t size, size_t blksize)
+ {
+ return ((size + blksize - 1) / blksize) * blksize;
+ }
+
+ /**
+ * dir_crypt_complete() -
+ */
+ static void dir_crypt_complete(struct crypto_async_request *req, int res)
+ {
+ struct fscrypt_completion_result *ecr = req->data;
+
+ if (res == -EINPROGRESS)
+ return;
+ ecr->res = res;
+ complete(&ecr->completion);
+ }
+
+ /**
+ * fname_encrypt() -
+ *
+ * This function encrypts the input filename, and returns the length of the
+ * ciphertext. Errors are returned as negative numbers. We trust the caller to
+ * allocate sufficient memory to oname string.
+ */
+ static int fname_encrypt(struct inode *inode,
+ const struct qstr *iname, struct fscrypt_str *oname)
+ {
+ u32 ciphertext_len;
- struct crypto_ablkcipher *tfm = ci->ci_ctfm;
++ struct skcipher_request *req = NULL;
+ DECLARE_FS_COMPLETION_RESULT(ecr);
+ struct fscrypt_info *ci = inode->i_crypt_info;
- req = ablkcipher_request_alloc(tfm, GFP_NOFS);
++ struct crypto_skcipher *tfm = ci->ci_ctfm;
+ int res = 0;
+ char iv[FS_CRYPTO_BLOCK_SIZE];
+ struct scatterlist src_sg, dst_sg;
+ int padding = 4 << (ci->ci_flags & FS_POLICY_FLAGS_PAD_MASK);
+ char *workbuf, buf[32], *alloc_buf = NULL;
+ unsigned lim;
+
+ lim = inode->i_sb->s_cop->max_namelen(inode);
+ if (iname->len <= 0 || iname->len > lim)
+ return -EIO;
+
+ ciphertext_len = (iname->len < FS_CRYPTO_BLOCK_SIZE) ?
+ FS_CRYPTO_BLOCK_SIZE : iname->len;
+ ciphertext_len = size_round_up(ciphertext_len, padding);
+ ciphertext_len = (ciphertext_len > lim) ? lim : ciphertext_len;
+
+ if (ciphertext_len <= sizeof(buf)) {
+ workbuf = buf;
+ } else {
+ alloc_buf = kmalloc(ciphertext_len, GFP_NOFS);
+ if (!alloc_buf)
+ return -ENOMEM;
+ workbuf = alloc_buf;
+ }
+
+ /* Allocate request */
- ablkcipher_request_set_callback(req,
++ req = skcipher_request_alloc(tfm, GFP_NOFS);
+ if (!req) {
+ printk_ratelimited(KERN_ERR
+ "%s: crypto_request_alloc() failed\n", __func__);
+ kfree(alloc_buf);
+ return -ENOMEM;
+ }
- ablkcipher_request_set_crypt(req, &src_sg, &dst_sg, ciphertext_len, iv);
- res = crypto_ablkcipher_encrypt(req);
++ skcipher_request_set_callback(req,
+ CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
+ dir_crypt_complete, &ecr);
+
+ /* Copy the input */
+ memcpy(workbuf, iname->name, iname->len);
+ if (iname->len < ciphertext_len)
+ memset(workbuf + iname->len, 0, ciphertext_len - iname->len);
+
+ /* Initialize IV */
+ memset(iv, 0, FS_CRYPTO_BLOCK_SIZE);
+
+ /* Create encryption request */
+ sg_init_one(&src_sg, workbuf, ciphertext_len);
+ sg_init_one(&dst_sg, oname->name, ciphertext_len);
- ablkcipher_request_free(req);
++ skcipher_request_set_crypt(req, &src_sg, &dst_sg, ciphertext_len, iv);
++ res = crypto_skcipher_encrypt(req);
+ if (res == -EINPROGRESS || res == -EBUSY) {
+ wait_for_completion(&ecr.completion);
+ res = ecr.res;
+ }
+ kfree(alloc_buf);
- struct ablkcipher_request *req = NULL;
++ skcipher_request_free(req);
+ if (res < 0)
+ printk_ratelimited(KERN_ERR
+ "%s: Error (error code %d)\n", __func__, res);
+
+ oname->len = ciphertext_len;
+ return res;
+ }
+
+ /*
+ * fname_decrypt()
+ * This function decrypts the input filename, and returns
+ * the length of the plaintext.
+ * Errors are returned as negative numbers.
+ * We trust the caller to allocate sufficient memory to oname string.
+ */
+ static int fname_decrypt(struct inode *inode,
+ const struct fscrypt_str *iname,
+ struct fscrypt_str *oname)
+ {
- struct crypto_ablkcipher *tfm = ci->ci_ctfm;
++ struct skcipher_request *req = NULL;
+ DECLARE_FS_COMPLETION_RESULT(ecr);
+ struct scatterlist src_sg, dst_sg;
+ struct fscrypt_info *ci = inode->i_crypt_info;
- req = ablkcipher_request_alloc(tfm, GFP_NOFS);
++ struct crypto_skcipher *tfm = ci->ci_ctfm;
+ int res = 0;
+ char iv[FS_CRYPTO_BLOCK_SIZE];
+ unsigned lim;
+
+ lim = inode->i_sb->s_cop->max_namelen(inode);
+ if (iname->len <= 0 || iname->len > lim)
+ return -EIO;
+
+ /* Allocate request */
- ablkcipher_request_set_callback(req,
++ req = skcipher_request_alloc(tfm, GFP_NOFS);
+ if (!req) {
+ printk_ratelimited(KERN_ERR
+ "%s: crypto_request_alloc() failed\n", __func__);
+ return -ENOMEM;
+ }
- ablkcipher_request_set_crypt(req, &src_sg, &dst_sg, iname->len, iv);
- res = crypto_ablkcipher_decrypt(req);
++ skcipher_request_set_callback(req,
+ CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
+ dir_crypt_complete, &ecr);
+
+ /* Initialize IV */
+ memset(iv, 0, FS_CRYPTO_BLOCK_SIZE);
+
+ /* Create decryption request */
+ sg_init_one(&src_sg, iname->name, iname->len);
+ sg_init_one(&dst_sg, oname->name, oname->len);
- ablkcipher_request_free(req);
++ skcipher_request_set_crypt(req, &src_sg, &dst_sg, iname->len, iv);
++ res = crypto_skcipher_decrypt(req);
+ if (res == -EINPROGRESS || res == -EBUSY) {
+ wait_for_completion(&ecr.completion);
+ res = ecr.res;
+ }
++ skcipher_request_free(req);
+ if (res < 0) {
+ printk_ratelimited(KERN_ERR
+ "%s: Error (error code %d)\n", __func__, res);
+ return res;
+ }
+
+ oname->len = strnlen(oname->name, iname->len);
+ return oname->len;
+ }
+
+ static const char *lookup_table =
+ "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+,";
+
+ /**
+ * digest_encode() -
+ *
+ * Encodes the input digest using characters from the set [a-zA-Z0-9_+].
+ * The encoded string is roughly 4/3 times the size of the input string.
+ */
+ static int digest_encode(const char *src, int len, char *dst)
+ {
+ int i = 0, bits = 0, ac = 0;
+ char *cp = dst;
+
+ while (i < len) {
+ ac += (((unsigned char) src[i]) << bits);
+ bits += 8;
+ do {
+ *cp++ = lookup_table[ac & 0x3f];
+ ac >>= 6;
+ bits -= 6;
+ } while (bits >= 6);
+ i++;
+ }
+ if (bits)
+ *cp++ = lookup_table[ac & 0x3f];
+ return cp - dst;
+ }
+
+ static int digest_decode(const char *src, int len, char *dst)
+ {
+ int i = 0, bits = 0, ac = 0;
+ const char *p;
+ char *cp = dst;
+
+ while (i < len) {
+ p = strchr(lookup_table, src[i]);
+ if (p == NULL || src[i] == 0)
+ return -2;
+ ac += (p - lookup_table) << bits;
+ bits += 6;
+ if (bits >= 8) {
+ *cp++ = ac & 0xff;
+ ac >>= 8;
+ bits -= 8;
+ }
+ i++;
+ }
+ if (ac)
+ return -1;
+ return cp - dst;
+ }
+
+ u32 fscrypt_fname_encrypted_size(struct inode *inode, u32 ilen)
+ {
+ int padding = 32;
+ struct fscrypt_info *ci = inode->i_crypt_info;
+
+ if (ci)
+ padding = 4 << (ci->ci_flags & FS_POLICY_FLAGS_PAD_MASK);
+ if (ilen < FS_CRYPTO_BLOCK_SIZE)
+ ilen = FS_CRYPTO_BLOCK_SIZE;
+ return size_round_up(ilen, padding);
+ }
+ EXPORT_SYMBOL(fscrypt_fname_encrypted_size);
+
+ /**
+ * fscrypt_fname_crypto_alloc_obuff() -
+ *
+ * Allocates an output buffer that is sufficient for the crypto operation
+ * specified by the context and the direction.
+ */
+ int fscrypt_fname_alloc_buffer(struct inode *inode,
+ u32 ilen, struct fscrypt_str *crypto_str)
+ {
+ unsigned int olen = fscrypt_fname_encrypted_size(inode, ilen);
+
+ crypto_str->len = olen;
+ if (olen < FS_FNAME_CRYPTO_DIGEST_SIZE * 2)
+ olen = FS_FNAME_CRYPTO_DIGEST_SIZE * 2;
+ /*
+ * Allocated buffer can hold one more character to null-terminate the
+ * string
+ */
+ crypto_str->name = kmalloc(olen + 1, GFP_NOFS);
+ if (!(crypto_str->name))
+ return -ENOMEM;
+ return 0;
+ }
+ EXPORT_SYMBOL(fscrypt_fname_alloc_buffer);
+
+ /**
+ * fscrypt_fname_crypto_free_buffer() -
+ *
+ * Frees the buffer allocated for crypto operation.
+ */
+ void fscrypt_fname_free_buffer(struct fscrypt_str *crypto_str)
+ {
+ if (!crypto_str)
+ return;
+ kfree(crypto_str->name);
+ crypto_str->name = NULL;
+ }
+ EXPORT_SYMBOL(fscrypt_fname_free_buffer);
+
+ /**
+ * fscrypt_fname_disk_to_usr() - converts a filename from disk space to user
+ * space
+ */
+ int fscrypt_fname_disk_to_usr(struct inode *inode,
+ u32 hash, u32 minor_hash,
+ const struct fscrypt_str *iname,
+ struct fscrypt_str *oname)
+ {
+ const struct qstr qname = FSTR_TO_QSTR(iname);
+ char buf[24];
+ int ret;
+
+ if (fscrypt_is_dot_dotdot(&qname)) {
+ oname->name[0] = '.';
+ oname->name[iname->len - 1] = '.';
+ oname->len = iname->len;
+ return oname->len;
+ }
+
+ if (iname->len < FS_CRYPTO_BLOCK_SIZE)
+ return -EUCLEAN;
+
+ if (inode->i_crypt_info)
+ return fname_decrypt(inode, iname, oname);
+
+ if (iname->len <= FS_FNAME_CRYPTO_DIGEST_SIZE) {
+ ret = digest_encode(iname->name, iname->len, oname->name);
+ oname->len = ret;
+ return ret;
+ }
+ if (hash) {
+ memcpy(buf, &hash, 4);
+ memcpy(buf + 4, &minor_hash, 4);
+ } else {
+ memset(buf, 0, 8);
+ }
+ memcpy(buf + 8, iname->name + iname->len - 16, 16);
+ oname->name[0] = '_';
+ ret = digest_encode(buf, 24, oname->name + 1);
+ oname->len = ret + 1;
+ return ret + 1;
+ }
+ EXPORT_SYMBOL(fscrypt_fname_disk_to_usr);
+
+ /**
+ * fscrypt_fname_usr_to_disk() - converts a filename from user space to disk
+ * space
+ */
+ 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 oname->len;
+ }
+ 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 -EACCES;
+ }
+ EXPORT_SYMBOL(fscrypt_fname_usr_to_disk);
+
+ int fscrypt_setup_filename(struct inode *dir, const struct qstr *iname,
+ int lookup, struct fscrypt_name *fname)
+ {
+ int ret = 0, bigname = 0;
+
+ memset(fname, 0, sizeof(struct fscrypt_name));
+ fname->usr_fname = iname;
+
+ if (!dir->i_sb->s_cop->is_encrypted(dir) ||
+ fscrypt_is_dot_dotdot(iname)) {
+ fname->disk_name.name = (unsigned char *)iname->name;
+ fname->disk_name.len = iname->len;
+ return 0;
+ }
+ ret = get_crypt_info(dir);
+ if (ret && ret != -EOPNOTSUPP)
+ return ret;
+
+ if (dir->i_crypt_info) {
+ ret = fscrypt_fname_alloc_buffer(dir, iname->len,
+ &fname->crypto_buf);
+ if (ret < 0)
+ return ret;
+ ret = fname_encrypt(dir, iname, &fname->crypto_buf);
+ if (ret < 0)
+ goto errout;
+ fname->disk_name.name = fname->crypto_buf.name;
+ fname->disk_name.len = fname->crypto_buf.len;
+ return 0;
+ }
+ if (!lookup)
+ return -EACCES;
+
+ /*
+ * We don't have the key and we are doing a lookup; decode the
+ * user-supplied name
+ */
+ if (iname->name[0] == '_')
+ bigname = 1;
+ if ((bigname && (iname->len != 33)) || (!bigname && (iname->len > 43)))
+ return -ENOENT;
+
+ fname->crypto_buf.name = kmalloc(32, GFP_KERNEL);
+ if (fname->crypto_buf.name == NULL)
+ return -ENOMEM;
+
+ ret = digest_decode(iname->name + bigname, iname->len - bigname,
+ fname->crypto_buf.name);
+ if (ret < 0) {
+ ret = -ENOENT;
+ goto errout;
+ }
+ fname->crypto_buf.len = ret;
+ if (bigname) {
+ memcpy(&fname->hash, fname->crypto_buf.name, 4);
+ memcpy(&fname->minor_hash, fname->crypto_buf.name + 4, 4);
+ } else {
+ fname->disk_name.name = fname->crypto_buf.name;
+ fname->disk_name.len = fname->crypto_buf.len;
+ }
+ return 0;
+
+ errout:
+ fscrypt_fname_free_buffer(&fname->crypto_buf);
+ return ret;
+ }
+ EXPORT_SYMBOL(fscrypt_setup_filename);
+
+ void fscrypt_free_filename(struct fscrypt_name *fname)
+ {
+ kfree(fname->crypto_buf.name);
+ fname->crypto_buf.name = NULL;
+ fname->usr_fname = NULL;
+ fname->disk_name.name = NULL;
+ }
+ EXPORT_SYMBOL(fscrypt_free_filename);
--- /dev/null
-#include <crypto/hash.h>
+ /*
+ * key management facility for FS encryption support.
+ *
+ * Copyright (C) 2015, Google, Inc.
+ *
+ * This contains encryption key functions.
+ *
+ * Written by Michael Halcrow, Ildar Muslukhov, and Uday Savagaonkar, 2015.
+ */
+
+ #include <keys/encrypted-type.h>
+ #include <keys/user-type.h>
+ #include <linux/random.h>
+ #include <linux/scatterlist.h>
+ #include <uapi/linux/keyctl.h>
- struct ablkcipher_request *req = NULL;
+ #include <linux/fscrypto.h>
+
+ static void derive_crypt_complete(struct crypto_async_request *req, int rc)
+ {
+ struct fscrypt_completion_result *ecr = req->data;
+
+ if (rc == -EINPROGRESS)
+ return;
+
+ ecr->res = rc;
+ complete(&ecr->completion);
+ }
+
+ /**
+ * derive_key_aes() - Derive a key using AES-128-ECB
+ * @deriving_key: Encryption key used for derivation.
+ * @source_key: Source key to which to apply derivation.
+ * @derived_key: Derived key.
+ *
+ * Return: Zero on success; non-zero otherwise.
+ */
+ static int derive_key_aes(u8 deriving_key[FS_AES_128_ECB_KEY_SIZE],
+ u8 source_key[FS_AES_256_XTS_KEY_SIZE],
+ u8 derived_key[FS_AES_256_XTS_KEY_SIZE])
+ {
+ int res = 0;
- struct crypto_ablkcipher *tfm = crypto_alloc_ablkcipher("ecb(aes)", 0,
- 0);
++ struct skcipher_request *req = NULL;
+ DECLARE_FS_COMPLETION_RESULT(ecr);
+ struct scatterlist src_sg, dst_sg;
- crypto_ablkcipher_set_flags(tfm, CRYPTO_TFM_REQ_WEAK_KEY);
- req = ablkcipher_request_alloc(tfm, GFP_NOFS);
++ struct crypto_skcipher *tfm = crypto_alloc_skcipher("ecb(aes)", 0, 0);
+
+ if (IS_ERR(tfm)) {
+ res = PTR_ERR(tfm);
+ tfm = NULL;
+ goto out;
+ }
- ablkcipher_request_set_callback(req,
++ crypto_skcipher_set_flags(tfm, CRYPTO_TFM_REQ_WEAK_KEY);
++ req = skcipher_request_alloc(tfm, GFP_NOFS);
+ if (!req) {
+ res = -ENOMEM;
+ goto out;
+ }
- res = crypto_ablkcipher_setkey(tfm, deriving_key,
++ skcipher_request_set_callback(req,
+ CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
+ derive_crypt_complete, &ecr);
- ablkcipher_request_set_crypt(req, &src_sg, &dst_sg,
++ res = crypto_skcipher_setkey(tfm, deriving_key,
+ FS_AES_128_ECB_KEY_SIZE);
+ if (res < 0)
+ goto out;
+
+ sg_init_one(&src_sg, source_key, FS_AES_256_XTS_KEY_SIZE);
+ sg_init_one(&dst_sg, derived_key, FS_AES_256_XTS_KEY_SIZE);
- res = crypto_ablkcipher_encrypt(req);
++ skcipher_request_set_crypt(req, &src_sg, &dst_sg,
+ FS_AES_256_XTS_KEY_SIZE, NULL);
- if (req)
- ablkcipher_request_free(req);
- if (tfm)
- crypto_free_ablkcipher(tfm);
++ res = crypto_skcipher_encrypt(req);
+ if (res == -EINPROGRESS || res == -EBUSY) {
+ wait_for_completion(&ecr.completion);
+ res = ecr.res;
+ }
+ out:
- if (ci->ci_keyring_key)
- key_put(ci->ci_keyring_key);
- crypto_free_ablkcipher(ci->ci_ctfm);
++ skcipher_request_free(req);
++ crypto_free_skcipher(tfm);
+ return res;
+ }
+
+ static void put_crypt_info(struct fscrypt_info *ci)
+ {
+ if (!ci)
+ return;
+
- struct crypto_ablkcipher *ctfm;
++ key_put(ci->ci_keyring_key);
++ crypto_free_skcipher(ci->ci_ctfm);
+ kmem_cache_free(fscrypt_info_cachep, ci);
+ }
+
+ int get_crypt_info(struct inode *inode)
+ {
+ struct fscrypt_info *crypt_info;
+ u8 full_key_descriptor[FS_KEY_DESC_PREFIX_SIZE +
+ (FS_KEY_DESCRIPTOR_SIZE * 2) + 1];
+ struct key *keyring_key = NULL;
+ struct fscrypt_key *master_key;
+ struct fscrypt_context ctx;
+ const struct user_key_payload *ukp;
- ctfm = crypto_alloc_ablkcipher(cipher_str, 0, 0);
++ struct crypto_skcipher *ctfm;
+ const char *cipher_str;
+ u8 raw_key[FS_MAX_KEY_SIZE];
+ u8 mode;
+ int res;
+
+ res = fscrypt_initialize();
+ if (res)
+ return res;
+
+ if (!inode->i_sb->s_cop->get_context)
+ return -EOPNOTSUPP;
+ retry:
+ crypt_info = ACCESS_ONCE(inode->i_crypt_info);
+ if (crypt_info) {
+ if (!crypt_info->ci_keyring_key ||
+ key_validate(crypt_info->ci_keyring_key) == 0)
+ return 0;
+ fscrypt_put_encryption_info(inode, crypt_info);
+ goto retry;
+ }
+
+ res = inode->i_sb->s_cop->get_context(inode, &ctx, sizeof(ctx));
+ if (res < 0) {
+ if (!fscrypt_dummy_context_enabled(inode))
+ return res;
+ ctx.contents_encryption_mode = FS_ENCRYPTION_MODE_AES_256_XTS;
+ ctx.filenames_encryption_mode = FS_ENCRYPTION_MODE_AES_256_CTS;
+ ctx.flags = 0;
+ } else if (res != sizeof(ctx)) {
+ return -EINVAL;
+ }
+ res = 0;
+
+ crypt_info = kmem_cache_alloc(fscrypt_info_cachep, GFP_NOFS);
+ if (!crypt_info)
+ return -ENOMEM;
+
+ crypt_info->ci_flags = ctx.flags;
+ crypt_info->ci_data_mode = ctx.contents_encryption_mode;
+ crypt_info->ci_filename_mode = ctx.filenames_encryption_mode;
+ crypt_info->ci_ctfm = NULL;
+ crypt_info->ci_keyring_key = NULL;
+ memcpy(crypt_info->ci_master_key, ctx.master_key_descriptor,
+ sizeof(crypt_info->ci_master_key));
+ if (S_ISREG(inode->i_mode))
+ mode = crypt_info->ci_data_mode;
+ else if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))
+ mode = crypt_info->ci_filename_mode;
+ else
+ BUG();
+
+ switch (mode) {
+ case FS_ENCRYPTION_MODE_AES_256_XTS:
+ cipher_str = "xts(aes)";
+ break;
+ case FS_ENCRYPTION_MODE_AES_256_CTS:
+ cipher_str = "cts(cbc(aes))";
+ break;
+ default:
+ printk_once(KERN_WARNING
+ "%s: unsupported key mode %d (ino %u)\n",
+ __func__, mode, (unsigned) inode->i_ino);
+ res = -ENOKEY;
+ goto out;
+ }
+ if (fscrypt_dummy_context_enabled(inode)) {
+ memset(raw_key, 0x42, FS_AES_256_XTS_KEY_SIZE);
+ goto got_key;
+ }
+ memcpy(full_key_descriptor, FS_KEY_DESC_PREFIX,
+ FS_KEY_DESC_PREFIX_SIZE);
+ sprintf(full_key_descriptor + FS_KEY_DESC_PREFIX_SIZE,
+ "%*phN", FS_KEY_DESCRIPTOR_SIZE,
+ ctx.master_key_descriptor);
+ full_key_descriptor[FS_KEY_DESC_PREFIX_SIZE +
+ (2 * FS_KEY_DESCRIPTOR_SIZE)] = '\0';
+ keyring_key = request_key(&key_type_logon, full_key_descriptor, NULL);
+ if (IS_ERR(keyring_key)) {
+ res = PTR_ERR(keyring_key);
+ keyring_key = NULL;
+ goto out;
+ }
+ crypt_info->ci_keyring_key = keyring_key;
+ if (keyring_key->type != &key_type_logon) {
+ printk_once(KERN_WARNING
+ "%s: key type must be logon\n", __func__);
+ res = -ENOKEY;
+ goto out;
+ }
+ down_read(&keyring_key->sem);
+ ukp = user_key_payload(keyring_key);
+ if (ukp->datalen != sizeof(struct fscrypt_key)) {
+ res = -EINVAL;
+ up_read(&keyring_key->sem);
+ goto out;
+ }
+ master_key = (struct fscrypt_key *)ukp->data;
+ BUILD_BUG_ON(FS_AES_128_ECB_KEY_SIZE != FS_KEY_DERIVATION_NONCE_SIZE);
+
+ if (master_key->size != FS_AES_256_XTS_KEY_SIZE) {
+ printk_once(KERN_WARNING
+ "%s: key size incorrect: %d\n",
+ __func__, master_key->size);
+ res = -ENOKEY;
+ up_read(&keyring_key->sem);
+ goto out;
+ }
+ res = derive_key_aes(ctx.nonce, master_key->raw, raw_key);
+ up_read(&keyring_key->sem);
+ if (res)
+ goto out;
+ got_key:
- crypto_ablkcipher_clear_flags(ctfm, ~0);
- crypto_tfm_set_flags(crypto_ablkcipher_tfm(ctfm),
- CRYPTO_TFM_REQ_WEAK_KEY);
- res = crypto_ablkcipher_setkey(ctfm, raw_key, fscrypt_key_size(mode));
++ ctfm = crypto_alloc_skcipher(cipher_str, 0, 0);
+ if (!ctfm || IS_ERR(ctfm)) {
+ res = ctfm ? PTR_ERR(ctfm) : -ENOMEM;
+ printk(KERN_DEBUG
+ "%s: error %d (inode %u) allocating crypto tfm\n",
+ __func__, res, (unsigned) inode->i_ino);
+ goto out;
+ }
+ crypt_info->ci_ctfm = ctfm;
++ crypto_skcipher_clear_flags(ctfm, ~0);
++ crypto_skcipher_set_flags(ctfm, CRYPTO_TFM_REQ_WEAK_KEY);
++ res = crypto_skcipher_setkey(ctfm, raw_key, fscrypt_key_size(mode));
+ if (res)
+ goto out;
+
+ memzero_explicit(raw_key, sizeof(raw_key));
+ if (cmpxchg(&inode->i_crypt_info, NULL, crypt_info) != NULL) {
+ put_crypt_info(crypt_info);
+ goto retry;
+ }
+ return 0;
+
+ out:
+ if (res == -ENOKEY)
+ res = 0;
+ put_crypt_info(crypt_info);
+ memzero_explicit(raw_key, sizeof(raw_key));
+ return res;
+ }
+
+ void fscrypt_put_encryption_info(struct inode *inode, struct fscrypt_info *ci)
+ {
+ struct fscrypt_info *prev;
+
+ if (ci == NULL)
+ ci = ACCESS_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);
+ }
+ EXPORT_SYMBOL(fscrypt_put_encryption_info);
+
+ int fscrypt_get_encryption_info(struct inode *inode)
+ {
+ struct fscrypt_info *ci = inode->i_crypt_info;
+
+ if (!ci ||
+ (ci->ci_keyring_key &&
+ (ci->ci_keyring_key->flags & ((1 << KEY_FLAG_INVALIDATED) |
+ (1 << KEY_FLAG_REVOKED) |
+ (1 << KEY_FLAG_DEAD)))))
+ return get_crypt_info(inode);
+ return 0;
+ }
+ EXPORT_SYMBOL(fscrypt_get_encryption_info);
--- /dev/null
- struct crypto_ablkcipher *ci_ctfm;
+ /*
+ * General per-file encryption definition
+ *
+ * Copyright (C) 2015, Google, Inc.
+ *
+ * Written by Michael Halcrow, 2015.
+ * Modified by Jaegeuk Kim, 2015.
+ */
+
+ #ifndef _LINUX_FSCRYPTO_H
+ #define _LINUX_FSCRYPTO_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_KEY_DERIVATION_NONCE_SIZE 16
+ #define FS_ENCRYPTION_CONTEXT_FORMAT_V1 1
+
+ #define FS_POLICY_FLAGS_PAD_4 0x00
+ #define FS_POLICY_FLAGS_PAD_8 0x01
+ #define FS_POLICY_FLAGS_PAD_16 0x02
+ #define FS_POLICY_FLAGS_PAD_32 0x03
+ #define FS_POLICY_FLAGS_PAD_MASK 0x03
+ #define FS_POLICY_FLAGS_VALID 0x03
+
+ /* Encryption algorithms */
+ #define FS_ENCRYPTION_MODE_INVALID 0
+ #define FS_ENCRYPTION_MODE_AES_256_XTS 1
+ #define FS_ENCRYPTION_MODE_AES_256_GCM 2
+ #define FS_ENCRYPTION_MODE_AES_256_CBC 3
+ #define FS_ENCRYPTION_MODE_AES_256_CTS 4
+
+ /**
+ * Encryption context for inode
+ *
+ * Protector format:
+ * 1 byte: Protector format (1 = this version)
+ * 1 byte: File contents encryption mode
+ * 1 byte: File names encryption mode
+ * 1 byte: Flags
+ * 8 bytes: Master Key descriptor
+ * 16 bytes: Encryption Key derivation nonce
+ */
+ struct fscrypt_context {
+ u8 format;
+ u8 contents_encryption_mode;
+ u8 filenames_encryption_mode;
+ u8 flags;
+ u8 master_key_descriptor[FS_KEY_DESCRIPTOR_SIZE];
+ u8 nonce[FS_KEY_DERIVATION_NONCE_SIZE];
+ } __packed;
+
+ /* Encryption parameters */
+ #define FS_XTS_TWEAK_SIZE 16
+ #define FS_AES_128_ECB_KEY_SIZE 16
+ #define FS_AES_256_GCM_KEY_SIZE 32
+ #define FS_AES_256_CBC_KEY_SIZE 32
+ #define FS_AES_256_CTS_KEY_SIZE 32
+ #define FS_AES_256_XTS_KEY_SIZE 64
+ #define FS_MAX_KEY_SIZE 64
+
+ #define FS_KEY_DESC_PREFIX "fscrypt:"
+ #define FS_KEY_DESC_PREFIX_SIZE 8
+
+ /* This is passed in from userspace into the kernel keyring */
+ struct fscrypt_key {
+ u32 mode;
+ u8 raw[FS_MAX_KEY_SIZE];
+ u32 size;
+ } __packed;
+
+ struct fscrypt_info {
+ u8 ci_data_mode;
+ u8 ci_filename_mode;
+ u8 ci_flags;
++ struct crypto_skcipher *ci_ctfm;
+ struct key *ci_keyring_key;
+ u8 ci_master_key[FS_KEY_DESCRIPTOR_SIZE];
+ };
+
+ #define FS_CTX_REQUIRES_FREE_ENCRYPT_FL 0x00000001
+ #define FS_WRITE_PATH_FL 0x00000002
+
+ 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 */
+ u8 mode; /* Encryption mode for tfm */
+ };
+
+ struct fscrypt_completion_result {
+ struct completion completion;
+ int res;
+ };
+
+ #define DECLARE_FS_COMPLETION_RESULT(ecr) \
+ struct fscrypt_completion_result ecr = { \
+ COMPLETION_INITIALIZER((ecr).completion), 0 }
+
+ static inline int fscrypt_key_size(int mode)
+ {
+ switch (mode) {
+ case FS_ENCRYPTION_MODE_AES_256_XTS:
+ return FS_AES_256_XTS_KEY_SIZE;
+ case FS_ENCRYPTION_MODE_AES_256_GCM:
+ return FS_AES_256_GCM_KEY_SIZE;
+ case FS_ENCRYPTION_MODE_AES_256_CBC:
+ return FS_AES_256_CBC_KEY_SIZE;
+ case FS_ENCRYPTION_MODE_AES_256_CTS:
+ return FS_AES_256_CTS_KEY_SIZE;
+ default:
+ BUG();
+ }
+ return 0;
+ }
+
+ #define FS_FNAME_NUM_SCATTER_ENTRIES 4
+ #define FS_CRYPTO_BLOCK_SIZE 16
+ #define FS_FNAME_CRYPTO_DIGEST_SIZE 32
+
+ /**
+ * 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;
+
+ /**
+ * This function is used to calculate the disk space required to
+ * store a filename of length l in encrypted symlink format.
+ */
+ static inline u32 fscrypt_symlink_data_len(u32 l)
+ {
+ if (l < FS_CRYPTO_BLOCK_SIZE)
+ l = FS_CRYPTO_BLOCK_SIZE;
+ return (l + sizeof(struct fscrypt_symlink_data) - 1);
+ }
+
+ struct fscrypt_str {
+ unsigned char *name;
+ u32 len;
+ };
+
+ struct fscrypt_name {
+ const struct qstr *usr_fname;
+ struct fscrypt_str disk_name;
+ u32 hash;
+ u32 minor_hash;
+ struct fscrypt_str crypto_buf;
+ };
+
+ #define FSTR_INIT(n, l) { .name = n, .len = l }
+ #define FSTR_TO_QSTR(f) QSTR_INIT((f)->name, (f)->len)
+ #define fname_name(p) ((p)->disk_name.name)
+ #define fname_len(p) ((p)->disk_name.len)
+
+ /*
+ * crypto opertions for filesystems
+ */
+ struct fscrypt_operations {
+ int (*get_context)(struct inode *, void *, size_t);
+ int (*prepare_context)(struct inode *);
+ int (*set_context)(struct inode *, const void *, size_t, void *);
+ int (*dummy_context)(struct inode *);
+ bool (*is_encrypted)(struct inode *);
+ bool (*empty_dir)(struct inode *);
+ unsigned (*max_namelen)(struct inode *);
+ };
+
+ 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_contents_enc_mode(u32 mode)
+ {
+ return (mode == FS_ENCRYPTION_MODE_AES_256_XTS);
+ }
+
+ static inline bool fscrypt_valid_filenames_enc_mode(u32 mode)
+ {
+ return (mode == FS_ENCRYPTION_MODE_AES_256_CTS);
+ }
+
+ static inline u32 fscrypt_validate_encryption_key_size(u32 mode, u32 size)
+ {
+ if (size == fscrypt_key_size(mode))
+ return size;
+ return 0;
+ }
+
+ 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;
+ }
+
+ static inline struct page *fscrypt_control_page(struct page *page)
+ {
+ #if IS_ENABLED(CONFIG_FS_ENCRYPTION)
+ return ((struct fscrypt_ctx *)page_private(page))->w.control_page;
+ #else
+ WARN_ON_ONCE(1);
+ return ERR_PTR(-EINVAL);
+ #endif
+ }
+
+ static inline int fscrypt_has_encryption_key(struct inode *inode)
+ {
+ #if IS_ENABLED(CONFIG_FS_ENCRYPTION)
+ return (inode->i_crypt_info != NULL);
+ #else
+ return 0;
+ #endif
+ }
+
+ static inline void fscrypt_set_encrypted_dentry(struct dentry *dentry)
+ {
+ #if IS_ENABLED(CONFIG_FS_ENCRYPTION)
+ spin_lock(&dentry->d_lock);
+ dentry->d_flags |= DCACHE_ENCRYPTED_WITH_KEY;
+ spin_unlock(&dentry->d_lock);
+ #endif
+ }
+
+ #if IS_ENABLED(CONFIG_FS_ENCRYPTION)
+ extern const struct dentry_operations fscrypt_d_ops;
+ #endif
+
+ static inline void fscrypt_set_d_op(struct dentry *dentry)
+ {
+ #if IS_ENABLED(CONFIG_FS_ENCRYPTION)
+ d_set_d_op(dentry, &fscrypt_d_ops);
+ #endif
+ }
+
+ #if IS_ENABLED(CONFIG_FS_ENCRYPTION)
+ /* crypto.c */
+ extern struct kmem_cache *fscrypt_info_cachep;
+ int fscrypt_initialize(void);
+
+ extern struct fscrypt_ctx *fscrypt_get_ctx(struct inode *);
+ extern void fscrypt_release_ctx(struct fscrypt_ctx *);
+ extern struct page *fscrypt_encrypt_page(struct inode *, struct page *);
+ extern int fscrypt_decrypt_page(struct page *);
+ extern void fscrypt_decrypt_bio_pages(struct fscrypt_ctx *, struct bio *);
+ extern void fscrypt_pullback_bio_page(struct page **, bool);
+ extern void fscrypt_restore_control_page(struct page *);
+ extern int fscrypt_zeroout_range(struct inode *, pgoff_t, sector_t,
+ unsigned int);
+ /* policy.c */
+ extern int fscrypt_process_policy(struct inode *,
+ const struct fscrypt_policy *);
+ extern int fscrypt_get_policy(struct inode *, struct fscrypt_policy *);
+ extern int fscrypt_has_permitted_context(struct inode *, struct inode *);
+ extern int fscrypt_inherit_context(struct inode *, struct inode *,
+ void *, bool);
+ /* keyinfo.c */
+ extern int get_crypt_info(struct inode *);
+ extern int fscrypt_get_encryption_info(struct inode *);
+ extern void fscrypt_put_encryption_info(struct inode *, struct fscrypt_info *);
+
+ /* fname.c */
+ extern int fscrypt_setup_filename(struct inode *, const struct qstr *,
+ int lookup, struct fscrypt_name *);
+ extern void fscrypt_free_filename(struct fscrypt_name *);
+ extern u32 fscrypt_fname_encrypted_size(struct inode *, u32);
+ extern int fscrypt_fname_alloc_buffer(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 *);
+ #endif
+
+ /* crypto.c */
+ static inline struct fscrypt_ctx *fscrypt_notsupp_get_ctx(struct inode *i)
+ {
+ return ERR_PTR(-EOPNOTSUPP);
+ }
+
+ static inline void fscrypt_notsupp_release_ctx(struct fscrypt_ctx *c)
+ {
+ return;
+ }
+
+ static inline struct page *fscrypt_notsupp_encrypt_page(struct inode *i,
+ struct page *p)
+ {
+ return ERR_PTR(-EOPNOTSUPP);
+ }
+
+ static inline int fscrypt_notsupp_decrypt_page(struct page *p)
+ {
+ return -EOPNOTSUPP;
+ }
+
+ static inline void fscrypt_notsupp_decrypt_bio_pages(struct fscrypt_ctx *c,
+ struct bio *b)
+ {
+ return;
+ }
+
+ static inline void fscrypt_notsupp_pullback_bio_page(struct page **p, bool b)
+ {
+ return;
+ }
+
+ static inline void fscrypt_notsupp_restore_control_page(struct page *p)
+ {
+ return;
+ }
+
+ static inline int fscrypt_notsupp_zeroout_range(struct inode *i, pgoff_t p,
+ sector_t s, unsigned int f)
+ {
+ return -EOPNOTSUPP;
+ }
+
+ /* policy.c */
+ static inline int fscrypt_notsupp_process_policy(struct inode *i,
+ const struct fscrypt_policy *p)
+ {
+ return -EOPNOTSUPP;
+ }
+
+ static inline int fscrypt_notsupp_get_policy(struct inode *i,
+ struct fscrypt_policy *p)
+ {
+ return -EOPNOTSUPP;
+ }
+
+ static inline int fscrypt_notsupp_has_permitted_context(struct inode *p,
+ struct inode *i)
+ {
+ return 0;
+ }
+
+ static inline int fscrypt_notsupp_inherit_context(struct inode *p,
+ struct inode *i, void *v, bool b)
+ {
+ return -EOPNOTSUPP;
+ }
+
+ /* keyinfo.c */
+ static inline int fscrypt_notsupp_get_encryption_info(struct inode *i)
+ {
+ return -EOPNOTSUPP;
+ }
+
+ static inline void fscrypt_notsupp_put_encryption_info(struct inode *i,
+ struct fscrypt_info *f)
+ {
+ return;
+ }
+
+ /* fname.c */
+ static inline int fscrypt_notsupp_setup_filename(struct inode *dir,
+ const struct qstr *iname,
+ int lookup, struct fscrypt_name *fname)
+ {
+ if (dir->i_sb->s_cop->is_encrypted(dir))
+ return -EOPNOTSUPP;
+
+ memset(fname, 0, sizeof(struct fscrypt_name));
+ fname->usr_fname = iname;
+ fname->disk_name.name = (unsigned char *)iname->name;
+ fname->disk_name.len = iname->len;
+ return 0;
+ }
+
+ static inline void fscrypt_notsupp_free_filename(struct fscrypt_name *fname)
+ {
+ return;
+ }
+
+ static inline u32 fscrypt_notsupp_fname_encrypted_size(struct inode *i, u32 s)
+ {
+ /* never happens */
+ WARN_ON(1);
+ return 0;
+ }
+
+ static inline int fscrypt_notsupp_fname_alloc_buffer(struct inode *inode,
+ u32 ilen, struct fscrypt_str *crypto_str)
+ {
+ return -EOPNOTSUPP;
+ }
+
+ static inline void fscrypt_notsupp_fname_free_buffer(struct fscrypt_str *c)
+ {
+ return;
+ }
+
+ static inline int fscrypt_notsupp_fname_disk_to_usr(struct inode *inode,
+ u32 hash, u32 minor_hash,
+ const struct fscrypt_str *iname,
+ struct fscrypt_str *oname)
+ {
+ return -EOPNOTSUPP;
+ }
+
+ static inline int fscrypt_notsupp_fname_usr_to_disk(struct inode *inode,
+ const struct qstr *iname,
+ struct fscrypt_str *oname)
+ {
+ return -EOPNOTSUPP;
+ }
+ #endif /* _LINUX_FSCRYPTO_H */
projects / cascardo / linux.git / commitdiff