1 files changed, 203 insertions, 0 deletions

diff --git a/src/lib/libcrypto/bn/bn_gcd.c b/src/lib/libcrypto/bn/bn_gcd.c
new file mode 100644
index 0000000000..071bba3b4b
--- /dev/null
+++ b/src/lib/libcrypto/bn/bn_gcd.c
@@ -0,0 +1,203 @@
+/* crypto/bn/bn_gcd.c */
+/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
+ * All rights reserved.
+ *
+ * This package is an SSL implementation written
+ * by Eric Young (eay@cryptsoft.com).
+ * The implementation was written so as to conform with Netscapes SSL.
+ * 
+ * This library is free for commercial and non-commercial use as long as
+ * the following conditions are aheared to.  The following conditions
+ * apply to all code found in this distribution, be it the RC4, RSA,
+ * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
+ * included with this distribution is covered by the same copyright terms
+ * except that the holder is Tim Hudson (tjh@cryptsoft.com).
+ * 
+ * Copyright remains Eric Young's, and as such any Copyright notices in
+ * the code are not to be removed.
+ * If this package is used in a product, Eric Young should be given attribution
+ * as the author of the parts of the library used.
+ * This can be in the form of a textual message at program startup or
+ * in documentation (online or textual) provided with the package.
+ * 
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *    "This product includes cryptographic software written by
+ *     Eric Young (eay@cryptsoft.com)"
+ *    The word 'cryptographic' can be left out if the rouines from the library
+ *    being used are not cryptographic related :-).
+ * 4. If you include any Windows specific code (or a derivative thereof) from 
+ *    the apps directory (application code) you must include an acknowledgement:
+ *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
+ * 
+ * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * 
+ * The licence and distribution terms for any publically available version or
+ * derivative of this code cannot be changed.  i.e. this code cannot simply be
+ * copied and put under another distribution licence
+ * [including the GNU Public Licence.]
+ */
+
+#include <stdio.h>
+#include "cryptlib.h"
+#include "bn_lcl.h"
+
+#ifndef NOPROTO
+static BIGNUM *euclid(BIGNUM *a, BIGNUM *b);
+#else
+static BIGNUM *euclid();
+#endif
+
+int BN_gcd(r,in_a,in_b,ctx)
+BIGNUM *r,*in_a,*in_b;
+BN_CTX *ctx;
+        {
+        BIGNUM *a,*b,*t;
+        int ret=0;
+
+        a=ctx->bn[ctx->tos];
+        b=ctx->bn[ctx->tos+1];
+
+        if (BN_copy(a,in_a) == NULL) goto err;
+        if (BN_copy(b,in_b) == NULL) goto err;
+
+        if (BN_cmp(a,b) < 0) { t=a; a=b; b=t; }
+        t=euclid(a,b);
+        if (t == NULL) goto err;
+
+        if (BN_copy(r,t) == NULL) goto err;
+        ret=1;
+err:
+        return(ret);
+        }
+
+static BIGNUM *euclid(a,b)
+BIGNUM *a,*b;
+        {
+        BIGNUM *t;
+        int shifts=0;
+
+        for (;;)
+                {
+                if (BN_is_zero(b))
+                        break;
+
+                if (BN_is_odd(a))
+                        {
+                        if (BN_is_odd(b))
+                                {
+                                if (!BN_sub(a,a,b)) goto err;
+                                if (!BN_rshift1(a,a)) goto err;
+                                if (BN_cmp(a,b) < 0)
+                                        { t=a; a=b; b=t; }
+                                }
+                        else            /* a odd - b even */
+                                {
+                                if (!BN_rshift1(b,b)) goto err;
+                                if (BN_cmp(a,b) < 0)
+                                        { t=a; a=b; b=t; }
+                                }
+                        }
+                else                    /* a is even */
+                        {
+                        if (BN_is_odd(b))
+                                {
+                                if (!BN_rshift1(a,a)) goto err;
+                                if (BN_cmp(a,b) < 0)
+                                        { t=a; a=b; b=t; }
+                                }
+                        else            /* a even - b even */
+                                {
+                                if (!BN_rshift1(a,a)) goto err;
+                                if (!BN_rshift1(b,b)) goto err;
+                                shifts++;
+                                }
+                        }
+                }
+        if (shifts)
+                {
+                if (!BN_lshift(a,a,shifts)) goto err;
+                }
+        return(a);
+err:
+        return(NULL);
+        }
+
+/* solves ax == 1 (mod n) */
+BIGNUM *BN_mod_inverse(a, n, ctx)
+BIGNUM *a;
+BIGNUM *n;
+BN_CTX *ctx;
+        {
+        BIGNUM *A,*B,*X,*Y,*M,*D,*R;
+        BIGNUM *ret=NULL,*T;
+        int sign;
+
+        A=ctx->bn[ctx->tos];
+        B=ctx->bn[ctx->tos+1];
+        X=ctx->bn[ctx->tos+2];
+        D=ctx->bn[ctx->tos+3];
+        M=ctx->bn[ctx->tos+4];
+        Y=ctx->bn[ctx->tos+5];
+        ctx->tos+=6;
+        R=BN_new();
+        if (R == NULL) goto err;
+
+        BN_zero(X);
+        BN_one(Y);
+        if (BN_copy(A,a) == NULL) goto err;
+        if (BN_copy(B,n) == NULL) goto err;
+        sign=1;
+
+        while (!BN_is_zero(B))
+                {
+                if (!BN_div(D,M,A,B,ctx)) goto err;
+                T=A;
+                A=B;
+                B=M;
+                /* T has a struct, M does not */
+
+                if (!BN_mul(T,D,X)) goto err;
+                if (!BN_add(T,T,Y)) goto err;
+                M=Y;
+                Y=X;
+                X=T;
+                sign= -sign;
+                }
+        if (sign < 0)
+                {
+                if (!BN_sub(Y,n,Y)) goto err;
+                }
+
+        if (BN_is_one(A))
+                { if (!BN_mod(R,Y,n,ctx)) goto err; }
+        else
+                {
+                BNerr(BN_F_BN_MOD_INVERSE,BN_R_NO_INVERSE);
+                goto err;
+                }
+        ret=R;
+err:
+        if ((ret == NULL) && (R != NULL)) BN_free(R);
+        ctx->tos-=6;
+        return(ret);
+        }
+