/* * Cryptographic API. * * Digest operations. * * Copyright (c) 2002 James Morris <jmorris@intercode.com.au> * * 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 <linux/mm.h>#include <linux/errno.h>#include <linux/hardirq.h>#include <linux/highmem.h>#include <linux/kernel.h>#include <linux/module.h>#include <linux/scatterlist.h> #include "internal.h"#include "scatterwalk.h" static int init(struct hash_desc *desc){	struct crypto_tfm *tfm = crypto_hash_tfm(desc->tfm); 	tfm->__crt_alg->cra_digest.dia_init(tfm);	return 0;} static int update2(struct hash_desc *desc,		   struct scatterlist *sg, unsigned int nbytes){	struct crypto_tfm *tfm = crypto_hash_tfm(desc->tfm);	unsigned int alignmask = crypto_tfm_alg_alignmask(tfm); 	if (!nbytes)		return 0; 	for (;;) {		struct page *pg = sg->page;		unsigned int offset = sg->offset;		unsigned int l = sg->length; 		if (unlikely(l > nbytes))			l = nbytes;		nbytes -= l; 		do {			unsigned int bytes_from_page = min(l, ((unsigned int)							   (PAGE_SIZE)) - 							   offset);			char *src = crypto_kmap(pg, 0);			char *p = src + offset; 			if (unlikely(offset & alignmask)) {				unsigned int bytes =					alignmask + 1 - (offset & alignmask);				bytes = min(bytes, bytes_from_page);				tfm->__crt_alg->cra_digest.dia_update(tfm, p,								      bytes);				p += bytes;				bytes_from_page -= bytes;				l -= bytes;			}			tfm->__crt_alg->cra_digest.dia_update(tfm, p,							      bytes_from_page);			crypto_kunmap(src, 0);			crypto_yield(desc->flags);			offset = 0;			pg++;			l -= bytes_from_page;		} while (l > 0); 		if (!nbytes)			break;		sg = sg_next(sg);	} 	return 0;} static int update(struct hash_desc *desc,		  struct scatterlist *sg, unsigned int nbytes){	if (WARN_ON_ONCE(in_irq()))		return -EDEADLK;	return update2(desc, sg, nbytes);} static int final(struct hash_desc *desc, u8 *out){	struct crypto_tfm *tfm = crypto_hash_tfm(desc->tfm);	unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);	struct digest_alg *digest = &tfm->__crt_alg->cra_digest; 	if (unlikely((unsigned long)out & alignmask)) {		unsigned long align = alignmask + 1;		unsigned long addr = (unsigned long)crypto_tfm_ctx(tfm);		u8 *dst = (u8 *)ALIGN(addr, align) +			  ALIGN(tfm->__crt_alg->cra_ctxsize, align); 		digest->dia_final(tfm, dst);		memcpy(out, dst, digest->dia_digestsize);	} else		digest->dia_final(tfm, out); 	return 0;} static int nosetkey(struct crypto_hash *tfm, const u8 *key, unsigned int keylen){	crypto_hash_clear_flags(tfm, CRYPTO_TFM_RES_MASK);	return -ENOSYS;} static int setkey(struct crypto_hash *hash, const u8 *key, unsigned int keylen){	struct crypto_tfm *tfm = crypto_hash_tfm(hash); 	crypto_hash_clear_flags(hash, CRYPTO_TFM_RES_MASK);	return tfm->__crt_alg->cra_digest.dia_setkey(tfm, key, keylen);} static int digest(struct hash_desc *desc,		  struct scatterlist *sg, unsigned int nbytes, u8 *out){	if (WARN_ON_ONCE(in_irq()))		return -EDEADLK; 	init(desc);	update2(desc, sg, nbytes);	return final(desc, out);} int crypto_init_digest_ops(struct crypto_tfm *tfm){	struct hash_tfm *ops = &tfm->crt_hash;	struct digest_alg *dalg = &tfm->__crt_alg->cra_digest; 	if (dalg->dia_digestsize > crypto_tfm_alg_blocksize(tfm))		return -EINVAL;		ops->init	= init;	ops->update	= update;	ops->final	= final;	ops->digest	= digest;	ops->setkey	= dalg->dia_setkey ? setkey : nosetkey;	ops->digestsize	= dalg->dia_digestsize;		return 0;} void crypto_exit_digest_ops(struct crypto_tfm *tfm){}