diff -drupN a/fs/crypto/crypto.c b/fs/crypto/crypto.c --- a/fs/crypto/crypto.c 2018-08-06 17:23:04.000000000 +0300 +++ b/fs/crypto/crypto.c 2022-06-12 05:28:14.000000000 +0300 @@ -24,10 +24,11 @@ #include #include #include -#include #include #include -#include +#include +#include +#include "fscrypt_private.h" static unsigned int num_prealloc_crypto_pages = 32; static unsigned int num_prealloc_crypto_ctxs = 128; @@ -50,6 +51,12 @@ static DEFINE_MUTEX(fscrypt_init_mutex); static struct kmem_cache *fscrypt_ctx_cachep; struct kmem_cache *fscrypt_info_cachep; +void fscrypt_enqueue_decrypt_work(struct work_struct *work) +{ + queue_work(fscrypt_read_workqueue, work); +} +EXPORT_SYMBOL(fscrypt_enqueue_decrypt_work); + /** * fscrypt_release_ctx() - Releases an encryption context * @ctx: The encryption context to release. @@ -63,7 +70,7 @@ void fscrypt_release_ctx(struct fscrypt_ { unsigned long flags; - if (ctx->flags & FS_WRITE_PATH_FL && ctx->w.bounce_page) { + if (ctx->flags & FS_CTX_HAS_BOUNCE_BUFFER_FL && ctx->w.bounce_page) { mempool_free(ctx->w.bounce_page, fscrypt_bounce_page_pool); ctx->w.bounce_page = NULL; } @@ -88,7 +95,7 @@ EXPORT_SYMBOL(fscrypt_release_ctx); * Return: An allocated and initialized encryption context on success; error * value or NULL otherwise. */ -struct fscrypt_ctx *fscrypt_get_ctx(struct inode *inode, gfp_t gfp_flags) +struct fscrypt_ctx *fscrypt_get_ctx(const struct inode *inode, gfp_t gfp_flags) { struct fscrypt_ctx *ctx = NULL; struct fscrypt_info *ci = inode->i_crypt_info; @@ -121,47 +128,39 @@ struct fscrypt_ctx *fscrypt_get_ctx(stru } else { ctx->flags &= ~FS_CTX_REQUIRES_FREE_ENCRYPT_FL; } - ctx->flags &= ~FS_WRITE_PATH_FL; + ctx->flags &= ~FS_CTX_HAS_BOUNCE_BUFFER_FL; return ctx; } EXPORT_SYMBOL(fscrypt_get_ctx); -/** - * page_crypt_complete() - completion callback for page crypto - * @req: The asynchronous cipher request context - * @res: The result of the cipher operation - */ -static void page_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); -} - -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, - gfp_t gfp_flags) +int fscrypt_do_page_crypto(const struct inode *inode, fscrypt_direction_t rw, + u64 lblk_num, struct page *src_page, + struct page *dest_page, unsigned int len, + unsigned int offs, gfp_t gfp_flags) { struct { __le64 index; - u8 padding[FS_XTS_TWEAK_SIZE - sizeof(__le64)]; - } xts_tweak; + u8 padding[FS_IV_SIZE - sizeof(__le64)]; + } iv; struct skcipher_request *req = NULL; - DECLARE_FS_COMPLETION_RESULT(ecr); + DECLARE_CRYPTO_WAIT(wait); struct scatterlist dst, src; struct fscrypt_info *ci = inode->i_crypt_info; struct crypto_skcipher *tfm = ci->ci_ctfm; int res = 0; + BUG_ON(len == 0); + + BUILD_BUG_ON(sizeof(iv) != FS_IV_SIZE); + BUILD_BUG_ON(AES_BLOCK_SIZE != FS_IV_SIZE); + iv.index = cpu_to_le64(lblk_num); + memset(iv.padding, 0, sizeof(iv.padding)); + + if (ci->ci_essiv_tfm != NULL) { + crypto_cipher_encrypt_one(ci->ci_essiv_tfm, (u8 *)&iv, + (u8 *)&iv); + } + req = skcipher_request_alloc(tfm, gfp_flags); if (!req) { printk_ratelimited(KERN_ERR @@ -172,26 +171,17 @@ static int do_page_crypto(struct inode * skcipher_request_set_callback( req, CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP, - page_crypt_complete, &ecr); - - BUILD_BUG_ON(sizeof(xts_tweak) != FS_XTS_TWEAK_SIZE); - xts_tweak.index = cpu_to_le64(index); - memset(xts_tweak.padding, 0, sizeof(xts_tweak.padding)); + crypto_req_done, &wait); sg_init_table(&dst, 1); - sg_set_page(&dst, dest_page, PAGE_SIZE, 0); + sg_set_page(&dst, dest_page, len, offs); sg_init_table(&src, 1); - sg_set_page(&src, src_page, PAGE_SIZE, 0); - skcipher_request_set_crypt(req, &src, &dst, PAGE_SIZE, &xts_tweak); + sg_set_page(&src, src_page, len, offs); + skcipher_request_set_crypt(req, &src, &dst, len, &iv); if (rw == FS_DECRYPT) - res = crypto_skcipher_decrypt(req); + res = crypto_wait_req(crypto_skcipher_decrypt(req), &wait); else - res = crypto_skcipher_encrypt(req); - if (res == -EINPROGRESS || res == -EBUSY) { - BUG_ON(req->base.data != &ecr); - wait_for_completion(&ecr.completion); - res = ecr.res; - } + res = crypto_wait_req(crypto_skcipher_encrypt(req), &wait); skcipher_request_free(req); if (res) { printk_ratelimited(KERN_ERR @@ -202,53 +192,86 @@ static int do_page_crypto(struct inode * return 0; } -static struct page *alloc_bounce_page(struct fscrypt_ctx *ctx, gfp_t gfp_flags) +struct page *fscrypt_alloc_bounce_page(struct fscrypt_ctx *ctx, + gfp_t gfp_flags) { ctx->w.bounce_page = mempool_alloc(fscrypt_bounce_page_pool, gfp_flags); if (ctx->w.bounce_page == NULL) return ERR_PTR(-ENOMEM); - ctx->flags |= FS_WRITE_PATH_FL; + ctx->flags |= FS_CTX_HAS_BOUNCE_BUFFER_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. - * @gfp_flags: The gfp flag for memory allocation + * @inode: The inode for which the encryption should take place + * @page: The page to encrypt. Must be locked for bounce-page + * encryption. + * @len: Length of data to encrypt in @page and encrypted + * data in returned page. + * @offs: Offset of data within @page and returned + * page holding encrypted data. + * @lblk_num: Logical block number. This must be unique for multiple + * calls with same inode, except when overwriting + * previously written data. + * @gfp_flags: The gfp flag for memory allocation * - * Allocates a ciphertext page and encrypts plaintext_page into it using the ctx - * encryption context. + * Encrypts @page using the ctx encryption context. Performs encryption + * either in-place or into a newly allocated bounce page. + * Called on the page write path. * - * Called on the page write path. The caller must call + * Bounce page allocation is the default. + * In this case, the contents of @page are encrypted and stored in an + * allocated bounce page. @page has to be locked and 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 + * In-place encryption is used by setting the FS_CFLG_OWN_PAGES flag in + * fscrypt_operations. Here, the input-page is returned with its content + * encrypted. + * + * Return: A 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, gfp_t gfp_flags) +struct page *fscrypt_encrypt_page(const struct inode *inode, + struct page *page, + unsigned int len, + unsigned int offs, + u64 lblk_num, gfp_t gfp_flags) + { struct fscrypt_ctx *ctx; - struct page *ciphertext_page = NULL; + struct page *ciphertext_page = page; int err; - BUG_ON(!PageLocked(plaintext_page)); + BUG_ON(len % FS_CRYPTO_BLOCK_SIZE != 0); + + if (inode->i_sb->s_cop->flags & FS_CFLG_OWN_PAGES) { + /* with inplace-encryption we just encrypt the page */ + err = fscrypt_do_page_crypto(inode, FS_ENCRYPT, lblk_num, page, + ciphertext_page, len, offs, + gfp_flags); + if (err) + return ERR_PTR(err); + + return ciphertext_page; + } + + BUG_ON(!PageLocked(page)); ctx = fscrypt_get_ctx(inode, gfp_flags); if (IS_ERR(ctx)) return (struct page *)ctx; /* The encryption operation will require a bounce page. */ - ciphertext_page = alloc_bounce_page(ctx, gfp_flags); + ciphertext_page = fscrypt_alloc_bounce_page(ctx, gfp_flags); 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, - gfp_flags); + ctx->w.control_page = page; + err = fscrypt_do_page_crypto(inode, FS_ENCRYPT, lblk_num, + page, ciphertext_page, len, offs, + gfp_flags); if (err) { ciphertext_page = ERR_PTR(err); goto errout; @@ -265,8 +288,13 @@ errout: EXPORT_SYMBOL(fscrypt_encrypt_page); /** - * f2crypt_decrypt_page() - Decrypts a page in-place - * @page: The page to decrypt. Must be locked. + * fscrypt_decrypt_page() - Decrypts a page in-place + * @inode: The corresponding inode for the page to decrypt. + * @page: The page to decrypt. Must be locked in case + * it is a writeback page (FS_CFLG_OWN_PAGES unset). + * @len: Number of bytes in @page to be decrypted. + * @offs: Start of data in @page. + * @lblk_num: Logical block number. * * Decrypts page in-place using the ctx encryption context. * @@ -274,76 +302,17 @@ EXPORT_SYMBOL(fscrypt_encrypt_page); * * Return: Zero on success, non-zero otherwise. */ -int fscrypt_decrypt_page(struct page *page) +int fscrypt_decrypt_page(const struct inode *inode, struct page *page, + unsigned int len, unsigned int offs, u64 lblk_num) { - BUG_ON(!PageLocked(page)); + if (!(inode->i_sb->s_cop->flags & FS_CFLG_OWN_PAGES)) + BUG_ON(!PageLocked(page)); - return do_page_crypto(page->mapping->host, - FS_DECRYPT, page->index, page, page, GFP_NOFS); + return fscrypt_do_page_crypto(inode, FS_DECRYPT, lblk_num, page, page, + len, offs, GFP_NOFS); } 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_SIZE); - - ctx = fscrypt_get_ctx(inode, GFP_NOFS); - if (IS_ERR(ctx)) - return PTR_ERR(ctx); - - ciphertext_page = alloc_bounce_page(ctx, GFP_NOWAIT); - 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, - GFP_NOFS); - if (err) - goto errout; - - bio = bio_alloc(GFP_NOWAIT, 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); - bio_set_op_attrs(bio, REQ_OP_WRITE, 0); - 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(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 @@ -358,7 +327,7 @@ static int fscrypt_d_revalidate(struct d return -ECHILD; dir = dget_parent(dentry); - if (!d_inode(dir)->i_sb->s_cop->is_encrypted(d_inode(dir))) { + if (!IS_ENCRYPTED(d_inode(dir))) { dput(dir); return 0; } @@ -392,63 +361,6 @@ const struct dentry_operations fscrypt_d }; 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; @@ -474,16 +386,21 @@ static void fscrypt_destroy(void) /** * fscrypt_initialize() - allocate major buffers for fs encryption. + * @cop_flags: fscrypt operations flags * * 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 fscrypt_initialize(unsigned int cop_flags) { int i, res = -ENOMEM; + /* No need to allocate a bounce page pool if this FS won't use it. */ + if (cop_flags & FS_CFLG_OWN_PAGES) + return 0; + mutex_lock(&fscrypt_init_mutex); if (fscrypt_bounce_page_pool) goto already_initialized; @@ -510,7 +427,6 @@ fail: mutex_unlock(&fscrypt_init_mutex); return res; } -EXPORT_SYMBOL(fscrypt_initialize); /** * fscrypt_init() - Set up for fs encryption. @@ -561,6 +477,8 @@ static void __exit fscrypt_exit(void) destroy_workqueue(fscrypt_read_workqueue); kmem_cache_destroy(fscrypt_ctx_cachep); kmem_cache_destroy(fscrypt_info_cachep); + + fscrypt_essiv_cleanup(); } module_exit(fscrypt_exit);