+++ /dev/null
-/* -*-c-*-
- *
- * $Id: counter.h,v 1.4 2004/04/08 01:36:15 mdw Exp $
- *
- * Block cipher counter mode (or long cycle mode)
- *
- * (c) 2000 Straylight/Edgeware
- */
-
-/*----- Licensing notice --------------------------------------------------*
- *
- * This file is part of Catacomb.
- *
- * Catacomb is free software; you can redistribute it and/or modify
- * it under the terms of the GNU Library General Public License as
- * published by the Free Software Foundation; either version 2 of the
- * License, or (at your option) any later version.
- *
- * Catacomb is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU Library General Public License for more details.
- *
- * You should have received a copy of the GNU Library General Public
- * License along with Catacomb; if not, write to the Free
- * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
- * MA 02111-1307, USA.
- */
-
-#ifndef CATACOMB_COUNTER_H
-#define CATACOMB_COUNTER_H
-
-#ifdef __cplusplus
- extern "C" {
-#endif
-
-/*----- Header files ------------------------------------------------------*/
-
-#include <stddef.h>
-
-#include <mLib/bits.h>
-
-#ifndef CATACOMB_GCIPHER_H
-# include "gcipher.h"
-#endif
-
-#ifndef CATACOMB_GRAND_H
-# include "grand.h"
-#endif
-
-/*----- Macros ------------------------------------------------------------*/
-
-/* --- @COUNTER_DECL@ --- *
- *
- * Arguments: @PRE@, @pre@ = prefixes for block cipher definitions
- *
- * Use: Makes declarations for counter mode.
- */
-
-#define COUNTER_DECL(PRE, pre) \
- \
-/* --- Counter mode context --- */ \
- \
-typedef struct pre##_counterctx { \
- pre##_ctx ctx; /* Underlying cipher context */ \
- unsigned off; /* Current offset in buffer */ \
- octet buf[PRE##_BLKSZ]; /* Output buffer */ \
- uint32 n[PRE##_BLKSZ / 4]; /* Counter */ \
-} pre##_counterctx; \
- \
-/* --- @pre_countergetiv@ --- * \
- * \
- * Arguments: @const pre_counterctx *ctx@ = pointer to counter \
- * context \
- * @void *iv@ = pointer to output data block \
- * \
- * Returns: --- \
- * \
- * Use: Reads the currently set IV. Reading and setting an IV \
- * is not transparent to the cipher. It will add a `step' \
- * which must be matched by a similar operation during \
- * decryption. \
- */ \
- \
-extern void pre##_countergetiv(const pre##_counterctx */*ctx*/, \
- void */*iv*/); \
- \
-/* --- @pre_countersetiv@ --- * \
- * \
- * Arguments: @pre_counterctx *ctx@ = pointer to counter context \
- * @cnost void *iv@ = pointer to IV to set \
- * \
- * Returns: --- \
- * \
- * Use: Sets the IV to use for subsequent encryption. \
- */ \
- \
-extern void pre##_countersetiv(pre##_counterctx */*ctx*/, \
- const void */*iv*/); \
- \
-/* --- @pre_counterbdry@ --- * \
- * \
- * Arguments: @pre_counterctx *ctx@ = pointer to counter context \
- * \
- * Returns: --- \
- * \
- * Use: Inserts a boundary during encryption. Successful \
- * decryption must place a similar boundary. \
- */ \
- \
-extern void pre##_counterbdry(pre##_counterctx */*ctx*/); \
- \
-/* --- @pre_countersetkey@ --- * \
- * \
- * Arguments: @pre_counterctx *ctx@ = pointer to counter context \
- * @const pre_ctx *k@ = pointer to cipher context \
- * \
- * Returns: --- \
- * \
- * Use: Sets the counter context to use a different cipher key. \
- */ \
- \
-extern void pre##_countersetkey(pre##_counterctx */*ctx*/, \
- const pre##_ctx */*k*/); \
- \
-/* --- @pre_counterinit@ --- * \
- * \
- * Arguments: @pre_counterctx *ctx@ = pointer to cipher context \
- * @const void *key@ = pointer to the key buffer \
- * @size_t sz@ = size of the key \
- * @const void *iv@ = pointer to initialization vector \
- * \
- * Returns: --- \
- * \
- * Use: Initializes a counter context ready for use. You \
- * should ensure that the IV chosen is unique: reusing an \
- * IV will compromise the security of the entire \
- * plaintext. This is equivalent to calls to @pre_init@, \
- * @pre_countersetkey@ and @pre_countersetiv@. \
- */ \
- \
-extern void pre##_counterinit(pre##_counterctx */*ctx*/, \
- const void */*key*/, size_t /*sz*/, \
- const void */*iv*/); \
- \
-/* --- @pre_counterencrypt@ --- * \
- * \
- * Arguments: @pre_counterctx *ctx@ = pointer to counter context \
- * @const void *src@ = pointer to source data \
- * @void *dest@ = pointer to destination data \
- * @size_t sz@ = size of block to be encrypted \
- * \
- * Returns: --- \
- * \
- * Use: Encrypts or decrypts a block with a block cipher in \
- * counter mode: encryption and decryption are the same in \
- * counter. The destination may be null to just churn the \
- * feedback round for a bit. The source may be null to \
- * use the cipher as a random data generator. \
- */ \
- \
-extern void pre##_counterencrypt(pre##_counterctx */*ctx*/, \
- const void */*src*/, void */*dest*/, \
- size_t /*sz*/); \
- \
-/* --- @pre_counterrand@ --- * \
- * \
- * Arguments: @const void *k@ = pointer to key material \
- * @size_t sz@ = size of key material \
- * \
- * Returns: Pointer to generic random number generator interface. \
- * \
- * Use: Creates a random number interface wrapper around an \
- * counter-mode block cipher. \
- */ \
- \
-extern grand *pre##_counterrand(const void */*k*/, size_t /*sz*/); \
- \
-/* --- Generic cipher interface --- */ \
- \
-extern const gccipher pre##_counter;
-
-/*----- That's all, folks -------------------------------------------------*/
-
-#ifdef __cplusplus
- }
-#endif
-
-#endif
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