diff --git a/Documentation/crypto/devel-algos.rst b/Documentation/crypto/devel-algos.rst index 3506899ef83e..9b7782f4f6e0 100644 --- a/Documentation/crypto/devel-algos.rst +++ b/Documentation/crypto/devel-algos.rst @@ -235,6 +235,4 @@ Specifics Of Asynchronous HASH Transformation Some of the drivers will want to use the Generic ScatterWalk in case the implementation needs to be fed separate chunks of the scatterlist which -contains the input data. The buffer containing the resulting hash will -always be properly aligned to .cra_alignmask so there is no need to -worry about this. +contains the input data. diff --git a/crypto/ahash.c b/crypto/ahash.c index 213bb3e9f245..744fd3b8ea25 100644 --- a/crypto/ahash.c +++ b/crypto/ahash.c @@ -35,21 +35,12 @@ struct ahash_request_priv { static int hash_walk_next(struct crypto_hash_walk *walk) { - unsigned int alignmask = walk->alignmask; unsigned int offset = walk->offset; unsigned int nbytes = min(walk->entrylen, ((unsigned int)(PAGE_SIZE)) - offset); walk->data = kmap_local_page(walk->pg); walk->data += offset; - - if (offset & alignmask) { - unsigned int unaligned = alignmask + 1 - (offset & alignmask); - - if (nbytes > unaligned) - nbytes = unaligned; - } - walk->entrylen -= nbytes; return nbytes; } @@ -73,23 +64,8 @@ static int hash_walk_new_entry(struct crypto_hash_walk *walk) int crypto_hash_walk_done(struct crypto_hash_walk *walk, int err) { - unsigned int alignmask = walk->alignmask; - walk->data -= walk->offset; - if (walk->entrylen && (walk->offset & alignmask) && !err) { - unsigned int nbytes; - - walk->offset = ALIGN(walk->offset, alignmask + 1); - nbytes = min(walk->entrylen, - (unsigned int)(PAGE_SIZE - walk->offset)); - if (nbytes) { - walk->entrylen -= nbytes; - walk->data += walk->offset; - return nbytes; - } - } - kunmap_local(walk->data); crypto_yield(walk->flags); @@ -121,7 +97,6 @@ int crypto_hash_walk_first(struct ahash_request *req, return 0; } - walk->alignmask = crypto_ahash_alignmask(crypto_ahash_reqtfm(req)); walk->sg = req->src; walk->flags = req->base.flags; @@ -129,26 +104,6 @@ int crypto_hash_walk_first(struct ahash_request *req, } EXPORT_SYMBOL_GPL(crypto_hash_walk_first); -static int ahash_setkey_unaligned(struct crypto_ahash *tfm, const u8 *key, - unsigned int keylen) -{ - unsigned long alignmask = crypto_ahash_alignmask(tfm); - int ret; - u8 *buffer, *alignbuffer; - unsigned long absize; - - absize = keylen + alignmask; - buffer = kmalloc(absize, GFP_KERNEL); - if (!buffer) - return -ENOMEM; - - alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1); - memcpy(alignbuffer, key, keylen); - ret = tfm->setkey(tfm, alignbuffer, keylen); - kfree_sensitive(buffer); - return ret; -} - static int ahash_nosetkey(struct crypto_ahash *tfm, const u8 *key, unsigned int keylen) { @@ -167,13 +122,7 @@ static void ahash_set_needkey(struct crypto_ahash *tfm) int crypto_ahash_setkey(struct crypto_ahash *tfm, const u8 *key, unsigned int keylen) { - unsigned long alignmask = crypto_ahash_alignmask(tfm); - int err; - - if ((unsigned long)key & alignmask) - err = ahash_setkey_unaligned(tfm, key, keylen); - else - err = tfm->setkey(tfm, key, keylen); + int err = tfm->setkey(tfm, key, keylen); if (unlikely(err)) { ahash_set_needkey(tfm); @@ -189,7 +138,6 @@ static int ahash_save_req(struct ahash_request *req, crypto_completion_t cplt, bool has_state) { struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); - unsigned long alignmask = crypto_ahash_alignmask(tfm); unsigned int ds = crypto_ahash_digestsize(tfm); struct ahash_request *subreq; unsigned int subreq_size; @@ -203,7 +151,6 @@ static int ahash_save_req(struct ahash_request *req, crypto_completion_t cplt, reqsize = ALIGN(reqsize, crypto_tfm_ctx_alignment()); subreq_size += reqsize; subreq_size += ds; - subreq_size += alignmask & ~(crypto_tfm_ctx_alignment() - 1); flags = ahash_request_flags(req); gfp = (flags & CRYPTO_TFM_REQ_MAY_SLEEP) ? GFP_KERNEL : GFP_ATOMIC; @@ -215,7 +162,6 @@ static int ahash_save_req(struct ahash_request *req, crypto_completion_t cplt, ahash_request_set_callback(subreq, flags, cplt, req); result = (u8 *)(subreq + 1) + reqsize; - result = PTR_ALIGN(result, alignmask + 1); ahash_request_set_crypt(subreq, req->src, result, req->nbytes); @@ -251,56 +197,6 @@ static void ahash_restore_req(struct ahash_request *req, int err) kfree_sensitive(subreq); } -static void ahash_op_unaligned_done(void *data, int err) -{ - struct ahash_request *areq = data; - - if (err == -EINPROGRESS) - goto out; - - /* First copy req->result into req->priv.result */ - ahash_restore_req(areq, err); - -out: - /* Complete the ORIGINAL request. */ - ahash_request_complete(areq, err); -} - -static int ahash_op_unaligned(struct ahash_request *req, - int (*op)(struct ahash_request *), - bool has_state) -{ - int err; - - err = ahash_save_req(req, ahash_op_unaligned_done, has_state); - if (err) - return err; - - err = op(req->priv); - if (err == -EINPROGRESS || err == -EBUSY) - return err; - - ahash_restore_req(req, err); - - return err; -} - -static int crypto_ahash_op(struct ahash_request *req, - int (*op)(struct ahash_request *), - bool has_state) -{ - struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); - unsigned long alignmask = crypto_ahash_alignmask(tfm); - int err; - - if ((unsigned long)req->result & alignmask) - err = ahash_op_unaligned(req, op, has_state); - else - err = op(req); - - return crypto_hash_errstat(crypto_hash_alg_common(tfm), err); -} - int crypto_ahash_final(struct ahash_request *req) { struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); @@ -309,7 +205,7 @@ int crypto_ahash_final(struct ahash_request *req) if (IS_ENABLED(CONFIG_CRYPTO_STATS)) atomic64_inc(&hash_get_stat(alg)->hash_cnt); - return crypto_ahash_op(req, tfm->final, true); + return crypto_hash_errstat(alg, tfm->final(req)); } EXPORT_SYMBOL_GPL(crypto_ahash_final); @@ -325,7 +221,7 @@ int crypto_ahash_finup(struct ahash_request *req) atomic64_add(req->nbytes, &istat->hash_tlen); } - return crypto_ahash_op(req, tfm->finup, true); + return crypto_hash_errstat(alg, tfm->finup(req)); } EXPORT_SYMBOL_GPL(crypto_ahash_finup); @@ -333,6 +229,7 @@ int crypto_ahash_digest(struct ahash_request *req) { struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); struct hash_alg_common *alg = crypto_hash_alg_common(tfm); + int err; if (IS_ENABLED(CONFIG_CRYPTO_STATS)) { struct crypto_istat_hash *istat = hash_get_stat(alg); @@ -342,9 +239,11 @@ int crypto_ahash_digest(struct ahash_request *req) } if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) - return crypto_hash_errstat(alg, -ENOKEY); + err = -ENOKEY; + else + err = tfm->digest(req); - return crypto_ahash_op(req, tfm->digest, false); + return crypto_hash_errstat(alg, err); } EXPORT_SYMBOL_GPL(crypto_ahash_digest); diff --git a/crypto/shash.c b/crypto/shash.c index 409b33f9c97c..359702c2cd02 100644 --- a/crypto/shash.c +++ b/crypto/shash.c @@ -541,6 +541,10 @@ int hash_prepare_alg(struct hash_alg_common *alg) if (alg->digestsize > HASH_MAX_DIGESTSIZE) return -EINVAL; + /* alignmask is not useful for hashes, so it is not supported. */ + if (base->cra_alignmask) + return -EINVAL; + base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK; if (IS_ENABLED(CONFIG_CRYPTO_STATS)) @@ -557,10 +561,6 @@ static int shash_prepare_alg(struct shash_alg *alg) if (alg->descsize > HASH_MAX_DESCSIZE) return -EINVAL; - /* alignmask is not useful for shash, so it is not supported. */ - if (base->cra_alignmask) - return -EINVAL; - if ((alg->export && !alg->import) || (alg->import && !alg->export)) return -EINVAL; diff --git a/include/crypto/internal/hash.h b/include/crypto/internal/hash.h index 8d0cd0c591a0..59c707e4dea4 100644 --- a/include/crypto/internal/hash.h +++ b/include/crypto/internal/hash.h @@ -18,15 +18,13 @@ struct crypto_hash_walk { char *data; unsigned int offset; - unsigned int alignmask; + unsigned int flags; struct page *pg; unsigned int entrylen; unsigned int total; struct scatterlist *sg; - - unsigned int flags; }; struct ahash_instance { diff --git a/include/linux/crypto.h b/include/linux/crypto.h index f3c3a3b27fac..b164da5e129e 100644 --- a/include/linux/crypto.h +++ b/include/linux/crypto.h @@ -110,7 +110,6 @@ * crypto_aead_walksize() (with the remainder going at the end), no chunk * can cross a page boundary or a scatterlist element boundary. * ahash: - * - The result buffer must be aligned to the algorithm's alignmask. * - crypto_ahash_finup() must not be used unless the algorithm implements * ->finup() natively. */ @@ -278,18 +277,20 @@ struct compress_alg { * @cra_ctxsize: Size of the operational context of the transformation. This * value informs the kernel crypto API about the memory size * needed to be allocated for the transformation context. - * @cra_alignmask: Alignment mask for the input and output data buffer. The data - * buffer containing the input data for the algorithm must be - * aligned to this alignment mask. The data buffer for the - * output data must be aligned to this alignment mask. Note that - * the Crypto API will do the re-alignment in software, but - * only under special conditions and there is a performance hit. - * The re-alignment happens at these occasions for different - * @cra_u types: cipher -- For both input data and output data - * buffer; ahash -- For output hash destination buf; shash -- - * For output hash destination buf. - * This is needed on hardware which is flawed by design and - * cannot pick data from arbitrary addresses. + * @cra_alignmask: For cipher, skcipher, lskcipher, and aead algorithms this is + * 1 less than the alignment, in bytes, that the algorithm + * implementation requires for input and output buffers. When + * the crypto API is invoked with buffers that are not aligned + * to this alignment, the crypto API automatically utilizes + * appropriately aligned temporary buffers to comply with what + * the algorithm needs. (For scatterlists this happens only if + * the algorithm uses the skcipher_walk helper functions.) This + * misalignment handling carries a performance penalty, so it is + * preferred that algorithms do not set a nonzero alignmask. + * Also, crypto API users may wish to allocate buffers aligned + * to the alignmask of the algorithm being used, in order to + * avoid the API having to realign them. Note: the alignmask is + * not supported for hash algorithms and is always 0 for them. * @cra_priority: Priority of this transformation implementation. In case * multiple transformations with same @cra_name are available to * the Crypto API, the kernel will use the one with highest