/* * 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/crypto.h>#include <linux/mm.h>#include <linux/errno.h>#include <linux/highmem.h>#include <asm/scatterlist.h>#include "internal.h" static void init(struct crypto_tfm *tfm){	tfm->__crt_alg->cra_digest.dia_init(crypto_tfm_ctx(tfm));} static void update(struct crypto_tfm *tfm,                   struct scatterlist *sg, unsigned int nsg){	unsigned int i; 	for (i = 0; i < nsg; i++) { 		struct page *pg = sg[i].page;		unsigned int offset = sg[i].offset;		unsigned int l = sg[i].length; 		do {			unsigned int bytes_from_page = min(l, ((unsigned int)							   (PAGE_SIZE)) - 							   offset);			char *p = crypto_kmap(pg, 0) + offset; 			tfm->__crt_alg->cra_digest.dia_update					(crypto_tfm_ctx(tfm), p,					 bytes_from_page);			crypto_kunmap(p, 0);			crypto_yield(tfm);			offset = 0;			pg++;			l -= bytes_from_page;		} while (l > 0);	}} static void final(struct crypto_tfm *tfm, u8 *out){	tfm->__crt_alg->cra_digest.dia_final(crypto_tfm_ctx(tfm), out);} static int setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen){	u32 flags;	if (tfm->__crt_alg->cra_digest.dia_setkey == NULL)		return -ENOSYS;	return tfm->__crt_alg->cra_digest.dia_setkey(crypto_tfm_ctx(tfm),						     key, keylen, &flags);} static void digest(struct crypto_tfm *tfm,                   struct scatterlist *sg, unsigned int nsg, u8 *out){	unsigned int i; 	tfm->crt_digest.dit_init(tfm);			for (i = 0; i < nsg; i++) {		char *p = crypto_kmap(sg[i].page, 0) + sg[i].offset;		tfm->__crt_alg->cra_digest.dia_update(crypto_tfm_ctx(tfm),		                                      p, sg[i].length);		crypto_kunmap(p, 0);		crypto_yield(tfm);	}	crypto_digest_final(tfm, out);} int crypto_init_digest_flags(struct crypto_tfm *tfm, u32 flags){	return flags ? -EINVAL : 0;} int crypto_init_digest_ops(struct crypto_tfm *tfm){	struct digest_tfm *ops = &tfm->crt_digest;		ops->dit_init	= init;	ops->dit_update	= update;	ops->dit_final	= final;	ops->dit_digest	= digest;	ops->dit_setkey	= setkey;		return crypto_alloc_hmac_block(tfm);} void crypto_exit_digest_ops(struct crypto_tfm *tfm){	crypto_free_hmac_block(tfm);}