Revert "lib/mpi: Extend the MPI library"

This partially reverts commit a8ea8bdd9df92a0e5db5b43900abb7a288b8a53e.

Most of it is no longer needed since sm2 has been removed.  However,
the following functions have been kept as they have developed other
uses:

mpi_copy

mpi_mod

mpi_test_bit
mpi_set_bit
mpi_rshift

mpi_add
mpi_sub
mpi_addm
mpi_subm

mpi_mul
mpi_mulm

mpi_tdiv_r
mpi_fdiv_r

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 0 insertions, 144 deletions

diff --git a/lib/crypto/mpi/mpi-mod.c b/lib/crypto/mpi/mpi-mod.c
index 54fcc01564d9..691bbdc52fc6 100644
--- a/lib/crypto/mpi/mpi-mod.c
+++ b/lib/crypto/mpi/mpi-mod.c
@@ -5,153 +5,9 @@
  * This file is part of Libgcrypt.
  */
 
-
 #include "mpi-internal.h"
-#include "longlong.h"
-
-/* Context used with Barrett reduction.  */
-struct barrett_ctx_s {
-	MPI m;   /* The modulus - may not be modified. */
-	int m_copied;   /* If true, M needs to be released.  */
-	int k;
-	MPI y;
-	MPI r1;  /* Helper MPI. */
-	MPI r2;  /* Helper MPI. */
-	MPI r3;  /* Helper MPI allocated on demand. */
-};
-
-
 
 void mpi_mod(MPI rem, MPI dividend, MPI divisor)
 {
 	mpi_fdiv_r(rem, dividend, divisor);
 }
-
-/* This function returns a new context for Barrett based operations on
- * the modulus M.  This context needs to be released using
- * _gcry_mpi_barrett_free.  If COPY is true M will be transferred to
- * the context and the user may change M.  If COPY is false, M may not
- * be changed until gcry_mpi_barrett_free has been called.
- */
-mpi_barrett_t mpi_barrett_init(MPI m, int copy)
-{
-	mpi_barrett_t ctx;
-	MPI tmp;
-
-	mpi_normalize(m);
-	ctx = kcalloc(1, sizeof(*ctx), GFP_KERNEL);
-	if (!ctx)
-		return NULL;
-
-	if (copy) {
-		ctx->m = mpi_copy(m);
-		ctx->m_copied = 1;
-	} else
-		ctx->m = m;
-
-	ctx->k = mpi_get_nlimbs(m);
-	tmp = mpi_alloc(ctx->k + 1);
-
-	/* Barrett precalculation: y = floor(b^(2k) / m). */
-	mpi_set_ui(tmp, 1);
-	mpi_lshift_limbs(tmp, 2 * ctx->k);
-	mpi_fdiv_q(tmp, tmp, m);
-
-	ctx->y  = tmp;
-	ctx->r1 = mpi_alloc(2 * ctx->k + 1);
-	ctx->r2 = mpi_alloc(2 * ctx->k + 1);
-
-	return ctx;
-}
-
-void mpi_barrett_free(mpi_barrett_t ctx)
-{
-	if (ctx) {
-		mpi_free(ctx->y);
-		mpi_free(ctx->r1);
-		mpi_free(ctx->r2);
-		if (ctx->r3)
-			mpi_free(ctx->r3);
-		if (ctx->m_copied)
-			mpi_free(ctx->m);
-		kfree(ctx);
-	}
-}
-
-
-/* R = X mod M
- *
- * Using Barrett reduction.  Before using this function
- * _gcry_mpi_barrett_init must have been called to do the
- * precalculations.  CTX is the context created by this precalculation
- * and also conveys M.  If the Barret reduction could no be done a
- * straightforward reduction method is used.
- *
- * We assume that these conditions are met:
- * Input:  x =(x_2k-1 ...x_0)_b
- *     m =(m_k-1 ....m_0)_b	  with m_k-1 != 0
- * Output: r = x mod m
- */
-void mpi_mod_barrett(MPI r, MPI x, mpi_barrett_t ctx)
-{
-	MPI m = ctx->m;
-	int k = ctx->k;
-	MPI y = ctx->y;
-	MPI r1 = ctx->r1;
-	MPI r2 = ctx->r2;
-	int sign;
-
-	mpi_normalize(x);
-	if (mpi_get_nlimbs(x) > 2*k) {
-		mpi_mod(r, x, m);
-		return;
-	}
-
-	sign = x->sign;
-	x->sign = 0;
-
-	/* 1. q1 = floor( x / b^k-1)
-	 *    q2 = q1 * y
-	 *    q3 = floor( q2 / b^k+1 )
-	 * Actually, we don't need qx, we can work direct on r2
-	 */
-	mpi_set(r2, x);
-	mpi_rshift_limbs(r2, k-1);
-	mpi_mul(r2, r2, y);
-	mpi_rshift_limbs(r2, k+1);
-
-	/* 2. r1 = x mod b^k+1
-	 *	r2 = q3 * m mod b^k+1
-	 *	r  = r1 - r2
-	 * 3. if r < 0 then  r = r + b^k+1
-	 */
-	mpi_set(r1, x);
-	if (r1->nlimbs > k+1) /* Quick modulo operation.  */
-		r1->nlimbs = k+1;
-	mpi_mul(r2, r2, m);
-	if (r2->nlimbs > k+1) /* Quick modulo operation. */
-		r2->nlimbs = k+1;
-	mpi_sub(r, r1, r2);
-
-	if (mpi_has_sign(r)) {
-		if (!ctx->r3) {
-			ctx->r3 = mpi_alloc(k + 2);
-			mpi_set_ui(ctx->r3, 1);
-			mpi_lshift_limbs(ctx->r3, k + 1);
-		}
-		mpi_add(r, r, ctx->r3);
-	}
-
-	/* 4. while r >= m do r = r - m */
-	while (mpi_cmp(r, m) >= 0)
-		mpi_sub(r, r, m);
-
-	x->sign = sign;
-}
-
-
-void mpi_mul_barrett(MPI w, MPI u, MPI v, mpi_barrett_t ctx)
-{
-	mpi_mul(w, u, v);
-	mpi_mod_barrett(w, w, ctx);
-}