| /* |
| * Asynchronous Cryptographic Hash operations. |
| * |
| * This is the asynchronous version of hash.c with notification of |
| * completion via a callback. |
| * |
| * Copyright (c) 2008 Loc Ho <lho@amcc.com> |
| * |
| * This program is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License as published by the Free |
| * Software Foundation; either version 2 of the License, or (at your option) |
| * any later version. |
| * |
| */ |
| |
| #include <crypto/internal/hash.h> |
| #include <crypto/scatterwalk.h> |
| #include <linux/err.h> |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/sched.h> |
| #include <linux/slab.h> |
| #include <linux/seq_file.h> |
| |
| #include "internal.h" |
| |
| static inline struct ahash_alg *crypto_ahash_alg(struct crypto_ahash *hash) |
| { |
| return container_of(crypto_hash_alg_common(hash), struct ahash_alg, |
| halg); |
| } |
| |
| 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 = crypto_kmap(walk->pg, 0); |
| walk->data += offset; |
| |
| if (offset & alignmask) |
| nbytes = alignmask + 1 - (offset & alignmask); |
| |
| walk->entrylen -= nbytes; |
| return nbytes; |
| } |
| |
| static int hash_walk_new_entry(struct crypto_hash_walk *walk) |
| { |
| struct scatterlist *sg; |
| |
| sg = walk->sg; |
| walk->pg = sg_page(sg); |
| walk->offset = sg->offset; |
| walk->entrylen = sg->length; |
| |
| if (walk->entrylen > walk->total) |
| walk->entrylen = walk->total; |
| walk->total -= walk->entrylen; |
| |
| return hash_walk_next(walk); |
| } |
| |
| int crypto_hash_walk_done(struct crypto_hash_walk *walk, int err) |
| { |
| unsigned int alignmask = walk->alignmask; |
| unsigned int nbytes = walk->entrylen; |
| |
| walk->data -= walk->offset; |
| |
| if (nbytes && walk->offset & alignmask && !err) { |
| walk->offset += alignmask - 1; |
| walk->offset = ALIGN(walk->offset, alignmask + 1); |
| walk->data += walk->offset; |
| |
| nbytes = min(nbytes, |
| ((unsigned int)(PAGE_SIZE)) - walk->offset); |
| walk->entrylen -= nbytes; |
| |
| return nbytes; |
| } |
| |
| crypto_kunmap(walk->data, 0); |
| crypto_yield(walk->flags); |
| |
| if (err) |
| return err; |
| |
| if (nbytes) { |
| walk->offset = 0; |
| walk->pg++; |
| return hash_walk_next(walk); |
| } |
| |
| if (!walk->total) |
| return 0; |
| |
| walk->sg = scatterwalk_sg_next(walk->sg); |
| |
| return hash_walk_new_entry(walk); |
| } |
| EXPORT_SYMBOL_GPL(crypto_hash_walk_done); |
| |
| int crypto_hash_walk_first(struct ahash_request *req, |
| struct crypto_hash_walk *walk) |
| { |
| walk->total = req->nbytes; |
| |
| if (!walk->total) |
| return 0; |
| |
| walk->alignmask = crypto_ahash_alignmask(crypto_ahash_reqtfm(req)); |
| walk->sg = req->src; |
| walk->flags = req->base.flags; |
| |
| return hash_walk_new_entry(walk); |
| } |
| EXPORT_SYMBOL_GPL(crypto_hash_walk_first); |
| |
| int crypto_hash_walk_first_compat(struct hash_desc *hdesc, |
| struct crypto_hash_walk *walk, |
| struct scatterlist *sg, unsigned int len) |
| { |
| walk->total = len; |
| |
| if (!walk->total) |
| return 0; |
| |
| walk->alignmask = crypto_hash_alignmask(hdesc->tfm); |
| walk->sg = sg; |
| walk->flags = hdesc->flags; |
| |
| return hash_walk_new_entry(walk); |
| } |
| |
| static int ahash_setkey_unaligned(struct crypto_ahash *tfm, const u8 *key, |
| unsigned int keylen) |
| { |
| struct ahash_alg *ahash = crypto_ahash_alg(tfm); |
| 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 = ahash->setkey(tfm, alignbuffer, keylen); |
| kzfree(buffer); |
| return ret; |
| } |
| |
| static int ahash_setkey(struct crypto_ahash *tfm, const u8 *key, |
| unsigned int keylen) |
| { |
| struct ahash_alg *ahash = crypto_ahash_alg(tfm); |
| unsigned long alignmask = crypto_ahash_alignmask(tfm); |
| |
| if ((unsigned long)key & alignmask) |
| return ahash_setkey_unaligned(tfm, key, keylen); |
| |
| return ahash->setkey(tfm, key, keylen); |
| } |
| |
| static int ahash_nosetkey(struct crypto_ahash *tfm, const u8 *key, |
| unsigned int keylen) |
| { |
| return -ENOSYS; |
| } |
| |
| static int crypto_ahash_init_tfm(struct crypto_tfm *tfm) |
| { |
| struct crypto_ahash *hash = __crypto_ahash_cast(tfm); |
| struct ahash_alg *alg = crypto_ahash_alg(hash); |
| |
| if (tfm->__crt_alg->cra_type != &crypto_ahash_type) |
| return crypto_init_shash_ops_async(tfm); |
| |
| hash->init = alg->init; |
| hash->update = alg->update; |
| hash->final = alg->final; |
| hash->digest = alg->digest; |
| hash->setkey = alg->setkey ? ahash_setkey : ahash_nosetkey; |
| |
| return 0; |
| } |
| |
| static unsigned int crypto_ahash_extsize(struct crypto_alg *alg) |
| { |
| if (alg->cra_type == &crypto_ahash_type) |
| return alg->cra_ctxsize; |
| |
| return sizeof(struct crypto_shash *); |
| } |
| |
| static void crypto_ahash_show(struct seq_file *m, struct crypto_alg *alg) |
| __attribute__ ((unused)); |
| static void crypto_ahash_show(struct seq_file *m, struct crypto_alg *alg) |
| { |
| seq_printf(m, "type : ahash\n"); |
| seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ? |
| "yes" : "no"); |
| seq_printf(m, "blocksize : %u\n", alg->cra_blocksize); |
| seq_printf(m, "digestsize : %u\n", |
| __crypto_hash_alg_common(alg)->digestsize); |
| } |
| |
| const struct crypto_type crypto_ahash_type = { |
| .extsize = crypto_ahash_extsize, |
| .init_tfm = crypto_ahash_init_tfm, |
| #ifdef CONFIG_PROC_FS |
| .show = crypto_ahash_show, |
| #endif |
| .maskclear = ~CRYPTO_ALG_TYPE_MASK, |
| .maskset = CRYPTO_ALG_TYPE_AHASH_MASK, |
| .type = CRYPTO_ALG_TYPE_AHASH, |
| .tfmsize = offsetof(struct crypto_ahash, base), |
| }; |
| EXPORT_SYMBOL_GPL(crypto_ahash_type); |
| |
| struct crypto_ahash *crypto_alloc_ahash(const char *alg_name, u32 type, |
| u32 mask) |
| { |
| return crypto_alloc_tfm(alg_name, &crypto_ahash_type, type, mask); |
| } |
| EXPORT_SYMBOL_GPL(crypto_alloc_ahash); |
| |
| static int ahash_prepare_alg(struct ahash_alg *alg) |
| { |
| struct crypto_alg *base = &alg->halg.base; |
| |
| if (alg->halg.digestsize > PAGE_SIZE / 8 || |
| alg->halg.statesize > PAGE_SIZE / 8) |
| return -EINVAL; |
| |
| base->cra_type = &crypto_ahash_type; |
| base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK; |
| base->cra_flags |= CRYPTO_ALG_TYPE_AHASH; |
| |
| return 0; |
| } |
| |
| int crypto_register_ahash(struct ahash_alg *alg) |
| { |
| struct crypto_alg *base = &alg->halg.base; |
| int err; |
| |
| err = ahash_prepare_alg(alg); |
| if (err) |
| return err; |
| |
| return crypto_register_alg(base); |
| } |
| EXPORT_SYMBOL_GPL(crypto_register_ahash); |
| |
| int crypto_unregister_ahash(struct ahash_alg *alg) |
| { |
| return crypto_unregister_alg(&alg->halg.base); |
| } |
| EXPORT_SYMBOL_GPL(crypto_unregister_ahash); |
| |
| int ahash_register_instance(struct crypto_template *tmpl, |
| struct ahash_instance *inst) |
| { |
| int err; |
| |
| err = ahash_prepare_alg(&inst->alg); |
| if (err) |
| return err; |
| |
| return crypto_register_instance(tmpl, ahash_crypto_instance(inst)); |
| } |
| EXPORT_SYMBOL_GPL(ahash_register_instance); |
| |
| void ahash_free_instance(struct crypto_instance *inst) |
| { |
| crypto_drop_spawn(crypto_instance_ctx(inst)); |
| kfree(ahash_instance(inst)); |
| } |
| EXPORT_SYMBOL_GPL(ahash_free_instance); |
| |
| int crypto_init_ahash_spawn(struct crypto_ahash_spawn *spawn, |
| struct hash_alg_common *alg, |
| struct crypto_instance *inst) |
| { |
| return crypto_init_spawn2(&spawn->base, &alg->base, inst, |
| &crypto_ahash_type); |
| } |
| EXPORT_SYMBOL_GPL(crypto_init_ahash_spawn); |
| |
| struct hash_alg_common *ahash_attr_alg(struct rtattr *rta, u32 type, u32 mask) |
| { |
| struct crypto_alg *alg; |
| |
| alg = crypto_attr_alg2(rta, &crypto_ahash_type, type, mask); |
| return IS_ERR(alg) ? ERR_CAST(alg) : __crypto_hash_alg_common(alg); |
| } |
| EXPORT_SYMBOL_GPL(ahash_attr_alg); |
| |
| MODULE_LICENSE("GPL"); |
| MODULE_DESCRIPTION("Asynchronous cryptographic hash type"); |