Moved to `rsa-priv.c'.

diff --git a/rsa-decrypt.c b/rsa-decrypt.c
deleted file mode 100644 (file)
index cbeed03..0000000
--- a/rsa-decrypt.c
+++ /dev/null
@@ -1,209 +0,0 @@
-/* -*-c-*-
- *
- * $Id: rsa-decrypt.c,v 1.2 2000/06/17 11:57:56 mdw Exp $
- *
- * RSA decryption
- *
- * (c) 1999 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.
- */
-
-/*----- Revision history --------------------------------------------------* 
- *
- * $Log: rsa-decrypt.c,v $
- * Revision 1.2  2000/06/17 11:57:56  mdw
- * Improve bulk performance by making better use of Montgomery
- * multiplication and separating out initialization and finalization from
- * the main code.
- *
- * Revision 1.1  1999/12/22 15:50:45  mdw
- * Initial RSA support.
- *
- */
-
-/*----- Header files ------------------------------------------------------*/
-
-#include "mp.h"
-#include "mpmont.h"
-#include "mprand.h"
-#include "rsa.h"
-
-/*----- Main code ---------------------------------------------------------*/
-
-/* --- @rsa_deccreate@ --- *
- *
- * Arguments:  @rsa_decctx *rd@ = pointer to an RSA decryption context
- *             @rsa_priv *rp@ = pointer to RSA private key
- *             @grand *r@ = pointer to random number source for blinding
- *
- * Returns:    ---
- *
- * Use:                Initializes an RSA decryption context.  Keeping a context
- *             for several decryption or signing operations provides a minor
- *             performance benefit.
- *
- *             The random number source may be null if blinding is not
- *             desired.  This improves decryption speed, at the risk of
- *             permitting timing attacks.
- */
-
-void rsa_deccreate(rsa_decctx *rd, rsa_param *rp, grand *r)
-{
-  rd->rp = rp;
-  rd->r = r;
-  if (r)
-    mpmont_create(&rd->nm, rp->n);
-  mpmont_create(&rd->pm, rp->p);
-  mpmont_create(&rd->qm, rp->q);
-}
-
-/* --- @rsa_decdestroy@ --- *
- *
- * Arguments:  @rsa_decctx *rd@ = pointer to an RSA decryption context
- *
- * Returns:    ---
- *
- * Use:                Destroys an RSA decryption context.
- */
-
-void rsa_decdestroy(rsa_decctx *rd)
-{
-  if (rd->r)
-    mpmont_destroy(&rd->nm);
-  mpmont_destroy(&rd->pm);
-  mpmont_destroy(&rd->qm);
-}
-
-/* --- @rsa_dec@ --- *
- *
- * Arguments:  @rsa_decctx *rd@ = pointer to RSA decryption context
- *             @mp *d@ = destination
- *             @mp *c@ = ciphertext message
- *
- * Returns:    The recovered plaintext message.
- *
- * Use:                Performs RSA decryption.  This function takes advantage of
- *             knowledge of the key factors in order to speed up
- *             decryption.  It also blinds the ciphertext prior to
- *             decryption and unblinds it afterwards to thwart timing
- *             attacks.
- */
-
-mp *rsa_dec(rsa_decctx *rd, mp *d, mp *c)
-{
-  mp *ki = MP_NEW;
-  rsa_param *rp = rd->rp;
-
-  /* --- If so desired, set up a blinding constant --- *
-   *
-   * Choose a constant %$k$% relatively prime to the modulus %$m$%.  Compute
-   * %$c' = c k^e \bmod n$%, and %$k^{-1} \bmod n$%.  Don't bother with the
-   * CRT stuff here because %$e$% is chosen to be small.
-   */
-
-  c = MP_COPY(c);
-  if (rd->r) {
-    mp *k = MP_NEWSEC, *g = MP_NEW;
-
-    do {
-      k = mprand_range(k, rp->n, rd->r, 0);
-      mp_gcd(&g, 0, &ki, rp->n, k);
-    } while (MP_CMP(g, !=, MP_ONE));
-    k = mpmont_expr(&rd->nm, k, k, rp->e);
-    c = mpmont_mul(&rd->nm, c, c, k);
-    mp_drop(k);
-    mp_drop(g);
-  }
-
-  /* --- Do the actual modular exponentiation --- *
-   *
-   * Use a slightly hacked version of the Chinese Remainder Theorem stuff.
-   *
-   * Let %$q' = q^{-1} \bmod p$%.  Then note that
-   * %$c^d \equiv q (q'(c_p^{d_p} - c_q^{d_q}) \bmod p) + c_q^{d_q} \pmod n$%
-   */
-
-  {
-    mp *cp = MP_NEW, *cq = MP_NEW;
-
-    /* --- Work out the two halves of the result --- */
-
-    mp_div(0, &cp, c, rp->p);
-    cp = mpmont_exp(&rd->pm, cp, cp, rp->dp);
-
-    mp_div(0, &cq, c, rp->q);
-    cq = mpmont_exp(&rd->qm, cq, cq, rp->dq);
-
-    /* --- Combine the halves using the result above --- */
-
-    d = mp_sub(d, cp, cq);
-    mp_div(0, &d, d, rp->p);
-    d = mpmont_mul(&rd->pm, d, d, rp->q_inv);
-    d = mpmont_mul(&rd->pm, d, d, rd->pm.r2);
-
-    d = mp_mul(d, d, rp->q);
-    d = mp_add(d, d, cq);
-    if (MP_CMP(d, >=, rp->n))
-      d = mp_sub(d, d, rp->n);
-
-    /* --- Tidy away temporary variables --- */
-
-    mp_drop(cp);
-    mp_drop(cq);
-  }
-
-  /* --- Finally, possibly remove the blinding factor --- */
-
-  if (ki) {
-    d = mpmont_mul(&rd->nm, d, d, ki);
-    d = mpmont_mul(&rd->nm, d, d, rd->nm.r2);
-    mp_drop(ki);
-  }
-
-  /* --- Done --- */
-
-  mp_drop(c);
-  return (d);
-}
-
-/* --- @rsa_decrypt@ --- *
- *
- * Arguments:  @rsa_param *rp@ = pointer to RSA parameters
- *             @mp *d@ = destination
- *             @mp *c@ = ciphertext message
- *             @grand *r@ = pointer to random number source for blinding
- *
- * Returns:    Correctly decrypted message.
- *
- * Use:                Performs RSA decryption, very carefully.
- */
-
-mp *rsa_decrypt(rsa_param *rp, mp *d, mp *c, grand *r)
-{
-  rsa_decctx rd;
-  rsa_deccreate(&rd, rp, r);
-  d = rsa_dec(&rd, d, c);
-  rsa_decdestroy(&rd);
-  return (d);
-}
-
-/*----- That's all, folks -------------------------------------------------*/