// SPDX-License-Identifier: GPL-2.0-or-later

  /*
   * Synchronous Cryptographic Hash operations.
   *
   * Copyright (c) 2008 Herbert Xu <herbert@gondor.apana.org.au>

   */

  #include <crypto/scatterwalk.h>

  #include <crypto/internal/hash.h>
  #include <linux/err.h>
  #include <linux/kernel.h>
  #include <linux/module.h>
  #include <linux/slab.h>
  #include <linux/seq_file.h>

  #include <linux/cryptouser.h>
  #include <net/netlink.h>

  #include <linux/compiler.h>

  #include "internal.h"

  static const struct crypto_type crypto_shash_type;

  int shash_no_setkey(struct crypto_shash *tfm, const u8 *key,
  		    unsigned int keylen)

  {
  	return -ENOSYS;
  }

  EXPORT_SYMBOL_GPL(shash_no_setkey);

  static int shash_setkey_unaligned(struct crypto_shash *tfm, const u8 *key,
  				  unsigned int keylen)
  {
  	struct shash_alg *shash = crypto_shash_alg(tfm);
  	unsigned long alignmask = crypto_shash_alignmask(tfm);
  	unsigned long absize;
  	u8 *buffer, *alignbuffer;
  	int err;

  	absize = keylen + (alignmask & ~(crypto_tfm_ctx_alignment() - 1));

  	buffer = kmalloc(absize, GFP_ATOMIC);

  	if (!buffer)
  		return -ENOMEM;
  
  	alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
  	memcpy(alignbuffer, key, keylen);
  	err = shash->setkey(tfm, alignbuffer, keylen);

  	kfree_sensitive(buffer);

  	return err;
  }

  static void shash_set_needkey(struct crypto_shash *tfm, struct shash_alg *alg)
  {

  	if (crypto_shash_alg_needs_key(alg))

  		crypto_shash_set_flags(tfm, CRYPTO_TFM_NEED_KEY);
  }

  int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key,
  			unsigned int keylen)
  {
  	struct shash_alg *shash = crypto_shash_alg(tfm);
  	unsigned long alignmask = crypto_shash_alignmask(tfm);

  	int err;

  
  	if ((unsigned long)key & alignmask)

  		err = shash_setkey_unaligned(tfm, key, keylen);
  	else
  		err = shash->setkey(tfm, key, keylen);

  	if (unlikely(err)) {
  		shash_set_needkey(tfm, shash);

  		return err;

  	}

  	crypto_shash_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
  	return 0;

  }
  EXPORT_SYMBOL_GPL(crypto_shash_setkey);

  static int shash_update_unaligned(struct shash_desc *desc, const u8 *data,
  				  unsigned int len)
  {
  	struct crypto_shash *tfm = desc->tfm;
  	struct shash_alg *shash = crypto_shash_alg(tfm);
  	unsigned long alignmask = crypto_shash_alignmask(tfm);
  	unsigned int unaligned_len = alignmask + 1 -
  				     ((unsigned long)data & alignmask);

  	/*
  	 * We cannot count on __aligned() working for large values:
  	 * https://patchwork.kernel.org/patch/9507697/
  	 */
  	u8 ubuf[MAX_ALGAPI_ALIGNMASK * 2];

  	u8 *buf = PTR_ALIGN(&ubuf[0], alignmask + 1);

  	int err;

  	if (WARN_ON(buf + unaligned_len > ubuf + sizeof(ubuf)))
  		return -EINVAL;

  	if (unaligned_len > len)
  		unaligned_len = len;

  	memcpy(buf, data, unaligned_len);

  	err = shash->update(desc, buf, unaligned_len);
  	memset(buf, 0, unaligned_len);

  	return err ?:

  	       shash->update(desc, data + unaligned_len, len - unaligned_len);
  }
  
  int crypto_shash_update(struct shash_desc *desc, const u8 *data,
  			unsigned int len)
  {
  	struct crypto_shash *tfm = desc->tfm;
  	struct shash_alg *shash = crypto_shash_alg(tfm);
  	unsigned long alignmask = crypto_shash_alignmask(tfm);
  
  	if ((unsigned long)data & alignmask)
  		return shash_update_unaligned(desc, data, len);
  
  	return shash->update(desc, data, len);
  }
  EXPORT_SYMBOL_GPL(crypto_shash_update);
  
  static int shash_final_unaligned(struct shash_desc *desc, u8 *out)
  {
  	struct crypto_shash *tfm = desc->tfm;
  	unsigned long alignmask = crypto_shash_alignmask(tfm);
  	struct shash_alg *shash = crypto_shash_alg(tfm);
  	unsigned int ds = crypto_shash_digestsize(tfm);

  	/*
  	 * We cannot count on __aligned() working for large values:
  	 * https://patchwork.kernel.org/patch/9507697/
  	 */
  	u8 ubuf[MAX_ALGAPI_ALIGNMASK + HASH_MAX_DIGESTSIZE];

  	u8 *buf = PTR_ALIGN(&ubuf[0], alignmask + 1);

  	int err;

  	if (WARN_ON(buf + ds > ubuf + sizeof(ubuf)))
  		return -EINVAL;

  	err = shash->final(desc, buf);

  	if (err)
  		goto out;

  	memcpy(out, buf, ds);

  
  out:
  	memset(buf, 0, ds);

  	return err;
  }
  
  int crypto_shash_final(struct shash_desc *desc, u8 *out)
  {
  	struct crypto_shash *tfm = desc->tfm;
  	struct shash_alg *shash = crypto_shash_alg(tfm);
  	unsigned long alignmask = crypto_shash_alignmask(tfm);
  
  	if ((unsigned long)out & alignmask)
  		return shash_final_unaligned(desc, out);
  
  	return shash->final(desc, out);
  }
  EXPORT_SYMBOL_GPL(crypto_shash_final);
  
  static int shash_finup_unaligned(struct shash_desc *desc, const u8 *data,
  				 unsigned int len, u8 *out)
  {
  	return crypto_shash_update(desc, data, len) ?:
  	       crypto_shash_final(desc, out);
  }
  
  int crypto_shash_finup(struct shash_desc *desc, const u8 *data,
  		       unsigned int len, u8 *out)
  {
  	struct crypto_shash *tfm = desc->tfm;
  	struct shash_alg *shash = crypto_shash_alg(tfm);
  	unsigned long alignmask = crypto_shash_alignmask(tfm);

  	if (((unsigned long)data | (unsigned long)out) & alignmask)

  		return shash_finup_unaligned(desc, data, len, out);
  
  	return shash->finup(desc, data, len, out);
  }
  EXPORT_SYMBOL_GPL(crypto_shash_finup);
  
  static int shash_digest_unaligned(struct shash_desc *desc, const u8 *data,
  				  unsigned int len, u8 *out)
  {
  	return crypto_shash_init(desc) ?:

  	       crypto_shash_finup(desc, data, len, out);

  }
  
  int crypto_shash_digest(struct shash_desc *desc, const u8 *data,
  			unsigned int len, u8 *out)
  {
  	struct crypto_shash *tfm = desc->tfm;
  	struct shash_alg *shash = crypto_shash_alg(tfm);
  	unsigned long alignmask = crypto_shash_alignmask(tfm);

  	if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
  		return -ENOKEY;

  	if (((unsigned long)data | (unsigned long)out) & alignmask)

  		return shash_digest_unaligned(desc, data, len, out);
  
  	return shash->digest(desc, data, len, out);
  }
  EXPORT_SYMBOL_GPL(crypto_shash_digest);

  int crypto_shash_tfm_digest(struct crypto_shash *tfm, const u8 *data,
  			    unsigned int len, u8 *out)
  {
  	SHASH_DESC_ON_STACK(desc, tfm);
  	int err;
  
  	desc->tfm = tfm;
  
  	err = crypto_shash_digest(desc, data, len, out);
  
  	shash_desc_zero(desc);
  
  	return err;
  }
  EXPORT_SYMBOL_GPL(crypto_shash_tfm_digest);

  static int shash_default_export(struct shash_desc *desc, void *out)

  {

  	memcpy(out, shash_desc_ctx(desc), crypto_shash_descsize(desc->tfm));
  	return 0;

  }

  static int shash_default_import(struct shash_desc *desc, const void *in)

  {

  	memcpy(shash_desc_ctx(desc), in, crypto_shash_descsize(desc->tfm));
  	return 0;

  }

  static int shash_async_setkey(struct crypto_ahash *tfm, const u8 *key,
  			      unsigned int keylen)
  {
  	struct crypto_shash **ctx = crypto_ahash_ctx(tfm);
  
  	return crypto_shash_setkey(*ctx, key, keylen);
  }
  
  static int shash_async_init(struct ahash_request *req)
  {
  	struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
  	struct shash_desc *desc = ahash_request_ctx(req);
  
  	desc->tfm = *ctx;

  
  	return crypto_shash_init(desc);
  }

  int shash_ahash_update(struct ahash_request *req, struct shash_desc *desc)

  {

  	struct crypto_hash_walk walk;
  	int nbytes;
  
  	for (nbytes = crypto_hash_walk_first(req, &walk); nbytes > 0;
  	     nbytes = crypto_hash_walk_done(&walk, nbytes))
  		nbytes = crypto_shash_update(desc, walk.data, nbytes);
  
  	return nbytes;
  }

  EXPORT_SYMBOL_GPL(shash_ahash_update);
  
  static int shash_async_update(struct ahash_request *req)
  {
  	return shash_ahash_update(req, ahash_request_ctx(req));
  }

  
  static int shash_async_final(struct ahash_request *req)
  {
  	return crypto_shash_final(ahash_request_ctx(req), req->result);
  }

  int shash_ahash_finup(struct ahash_request *req, struct shash_desc *desc)
  {
  	struct crypto_hash_walk walk;
  	int nbytes;

  	nbytes = crypto_hash_walk_first(req, &walk);
  	if (!nbytes)
  		return crypto_shash_final(desc, req->result);
  
  	do {

  		nbytes = crypto_hash_walk_last(&walk) ?
  			 crypto_shash_finup(desc, walk.data, nbytes,
  					    req->result) :
  			 crypto_shash_update(desc, walk.data, nbytes);

  		nbytes = crypto_hash_walk_done(&walk, nbytes);
  	} while (nbytes > 0);

  
  	return nbytes;
  }
  EXPORT_SYMBOL_GPL(shash_ahash_finup);
  
  static int shash_async_finup(struct ahash_request *req)
  {
  	struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
  	struct shash_desc *desc = ahash_request_ctx(req);
  
  	desc->tfm = *ctx;

  
  	return shash_ahash_finup(req, desc);
  }

  int shash_ahash_digest(struct ahash_request *req, struct shash_desc *desc)

  {

  	unsigned int nbytes = req->nbytes;

  	struct scatterlist *sg;
  	unsigned int offset;

  	int err;

  	if (nbytes &&
  	    (sg = req->src, offset = sg->offset,

  	     nbytes <= min(sg->length, ((unsigned int)(PAGE_SIZE)) - offset))) {

  		void *data;

  		data = kmap_atomic(sg_page(sg));

  		err = crypto_shash_digest(desc, data + offset, nbytes,
  					  req->result);

  		kunmap_atomic(data);

  	} else
  		err = crypto_shash_init(desc) ?:

  		      shash_ahash_finup(req, desc);

  	return err;
  }
  EXPORT_SYMBOL_GPL(shash_ahash_digest);

  static int shash_async_digest(struct ahash_request *req)
  {
  	struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
  	struct shash_desc *desc = ahash_request_ctx(req);

  	desc->tfm = *ctx;

  	return shash_ahash_digest(req, desc);

  }

  static int shash_async_export(struct ahash_request *req, void *out)
  {
  	return crypto_shash_export(ahash_request_ctx(req), out);
  }
  
  static int shash_async_import(struct ahash_request *req, const void *in)
  {

  	struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
  	struct shash_desc *desc = ahash_request_ctx(req);
  
  	desc->tfm = *ctx;

  
  	return crypto_shash_import(desc, in);

  }

  static void crypto_exit_shash_ops_async(struct crypto_tfm *tfm)
  {
  	struct crypto_shash **ctx = crypto_tfm_ctx(tfm);
  
  	crypto_free_shash(*ctx);
  }

  int crypto_init_shash_ops_async(struct crypto_tfm *tfm)

  {
  	struct crypto_alg *calg = tfm->__crt_alg;

  	struct shash_alg *alg = __crypto_shash_alg(calg);

  	struct crypto_ahash *crt = __crypto_ahash_cast(tfm);

  	struct crypto_shash **ctx = crypto_tfm_ctx(tfm);
  	struct crypto_shash *shash;
  
  	if (!crypto_mod_get(calg))
  		return -EAGAIN;

  	shash = crypto_create_tfm(calg, &crypto_shash_type);

  	if (IS_ERR(shash)) {
  		crypto_mod_put(calg);
  		return PTR_ERR(shash);
  	}
  
  	*ctx = shash;
  	tfm->exit = crypto_exit_shash_ops_async;
  
  	crt->init = shash_async_init;
  	crt->update = shash_async_update;

  	crt->final = shash_async_final;
  	crt->finup = shash_async_finup;

  	crt->digest = shash_async_digest;

  	if (crypto_shash_alg_has_setkey(alg))
  		crt->setkey = shash_async_setkey;

  	crypto_ahash_set_flags(crt, crypto_shash_get_flags(shash) &
  				    CRYPTO_TFM_NEED_KEY);

  	crt->export = shash_async_export;
  	crt->import = shash_async_import;

  	crt->reqsize = sizeof(struct shash_desc) + crypto_shash_descsize(shash);
  
  	return 0;
  }

  static void crypto_shash_exit_tfm(struct crypto_tfm *tfm)
  {
  	struct crypto_shash *hash = __crypto_shash_cast(tfm);
  	struct shash_alg *alg = crypto_shash_alg(hash);
  
  	alg->exit_tfm(hash);
  }

  static int crypto_shash_init_tfm(struct crypto_tfm *tfm)

  {

  	struct crypto_shash *hash = __crypto_shash_cast(tfm);

  	struct shash_alg *alg = crypto_shash_alg(hash);

  	int err;

  
  	hash->descsize = alg->descsize;

  	shash_set_needkey(hash, alg);

  	if (alg->exit_tfm)
  		tfm->exit = crypto_shash_exit_tfm;
  
  	if (!alg->init_tfm)
  		return 0;
  
  	err = alg->init_tfm(hash);
  	if (err)
  		return err;
  
  	/* ->init_tfm() may have increased the descsize. */
  	if (WARN_ON_ONCE(hash->descsize > HASH_MAX_DESCSIZE)) {
  		if (alg->exit_tfm)
  			alg->exit_tfm(hash);
  		return -EINVAL;
  	}

  	return 0;
  }

  static void crypto_shash_free_instance(struct crypto_instance *inst)
  {
  	struct shash_instance *shash = shash_instance(inst);

  	shash->free(shash);
  }

  #ifdef CONFIG_NET

  static int crypto_shash_report(struct sk_buff *skb, struct crypto_alg *alg)
  {
  	struct crypto_report_hash rhash;
  	struct shash_alg *salg = __crypto_shash_alg(alg);

  	memset(&rhash, 0, sizeof(rhash));
  
  	strscpy(rhash.type, "shash", sizeof(rhash.type));

  	rhash.blocksize = alg->cra_blocksize;
  	rhash.digestsize = salg->digestsize;

  	return nla_put(skb, CRYPTOCFGA_REPORT_HASH, sizeof(rhash), &rhash);

  }

  #else
  static int crypto_shash_report(struct sk_buff *skb, struct crypto_alg *alg)
  {
  	return -ENOSYS;
  }
  #endif

  static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg)

  	__maybe_unused;

  static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg)
  {
  	struct shash_alg *salg = __crypto_shash_alg(alg);
  
  	seq_printf(m, "type         : shash
  ");
  	seq_printf(m, "blocksize    : %u
  ", alg->cra_blocksize);
  	seq_printf(m, "digestsize   : %u
  ", salg->digestsize);

  }
  
  static const struct crypto_type crypto_shash_type = {

  	.extsize = crypto_alg_extsize,

  	.init_tfm = crypto_shash_init_tfm,

  	.free = crypto_shash_free_instance,

  #ifdef CONFIG_PROC_FS
  	.show = crypto_shash_show,
  #endif

  	.report = crypto_shash_report,

  	.maskclear = ~CRYPTO_ALG_TYPE_MASK,
  	.maskset = CRYPTO_ALG_TYPE_MASK,
  	.type = CRYPTO_ALG_TYPE_SHASH,
  	.tfmsize = offsetof(struct crypto_shash, base),
  };

  int crypto_grab_shash(struct crypto_shash_spawn *spawn,
  		      struct crypto_instance *inst,
  		      const char *name, u32 type, u32 mask)
  {
  	spawn->base.frontend = &crypto_shash_type;
  	return crypto_grab_spawn(&spawn->base, inst, name, type, mask);
  }
  EXPORT_SYMBOL_GPL(crypto_grab_shash);

  struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type,
  					u32 mask)
  {

  	return crypto_alloc_tfm(alg_name, &crypto_shash_type, type, mask);

  }
  EXPORT_SYMBOL_GPL(crypto_alloc_shash);

  static int shash_prepare_alg(struct shash_alg *alg)

  {
  	struct crypto_alg *base = &alg->base;

  	if (alg->digestsize > HASH_MAX_DIGESTSIZE ||
  	    alg->descsize > HASH_MAX_DESCSIZE ||
  	    alg->statesize > HASH_MAX_STATESIZE)

  		return -EINVAL;

  	if ((alg->export && !alg->import) || (alg->import && !alg->export))
  		return -EINVAL;

  	base->cra_type = &crypto_shash_type;
  	base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
  	base->cra_flags |= CRYPTO_ALG_TYPE_SHASH;

  	if (!alg->finup)
  		alg->finup = shash_finup_unaligned;
  	if (!alg->digest)
  		alg->digest = shash_digest_unaligned;

  	if (!alg->export) {
  		alg->export = shash_default_export;
  		alg->import = shash_default_import;
  		alg->statesize = alg->descsize;
  	}

  	if (!alg->setkey)
  		alg->setkey = shash_no_setkey;

  	return 0;
  }
  
  int crypto_register_shash(struct shash_alg *alg)
  {
  	struct crypto_alg *base = &alg->base;
  	int err;
  
  	err = shash_prepare_alg(alg);
  	if (err)
  		return err;

  
  	return crypto_register_alg(base);
  }
  EXPORT_SYMBOL_GPL(crypto_register_shash);

  void crypto_unregister_shash(struct shash_alg *alg)

  {

  	crypto_unregister_alg(&alg->base);

  }
  EXPORT_SYMBOL_GPL(crypto_unregister_shash);

  int crypto_register_shashes(struct shash_alg *algs, int count)
  {
  	int i, ret;
  
  	for (i = 0; i < count; i++) {
  		ret = crypto_register_shash(&algs[i]);
  		if (ret)
  			goto err;
  	}
  
  	return 0;
  
  err:
  	for (--i; i >= 0; --i)
  		crypto_unregister_shash(&algs[i]);
  
  	return ret;
  }
  EXPORT_SYMBOL_GPL(crypto_register_shashes);

  void crypto_unregister_shashes(struct shash_alg *algs, int count)

  {

  	int i;

  	for (i = count - 1; i >= 0; --i)
  		crypto_unregister_shash(&algs[i]);

  }
  EXPORT_SYMBOL_GPL(crypto_unregister_shashes);

  int shash_register_instance(struct crypto_template *tmpl,
  			    struct shash_instance *inst)
  {
  	int err;

  	if (WARN_ON(!inst->free))
  		return -EINVAL;

  	err = shash_prepare_alg(&inst->alg);
  	if (err)
  		return err;
  
  	return crypto_register_instance(tmpl, shash_crypto_instance(inst));
  }
  EXPORT_SYMBOL_GPL(shash_register_instance);

  void shash_free_singlespawn_instance(struct shash_instance *inst)

  {

  	crypto_drop_spawn(shash_instance_ctx(inst));
  	kfree(inst);

  }

  EXPORT_SYMBOL_GPL(shash_free_singlespawn_instance);

  MODULE_LICENSE("GPL");
  MODULE_DESCRIPTION("Synchronous cryptographic hash type");