1 files changed, 344 insertions, 33 deletions

diff --git a/src/lib/libcrypto/bn/bn_mont.c b/src/lib/libcrypto/bn/bn_mont.c
index 726d5f2b1b..4799b152dd 100644
--- a/src/lib/libcrypto/bn/bn_mont.c
+++ b/src/lib/libcrypto/bn/bn_mont.c
@@ -55,6 +55,59 @@
  * copied and put under another distribution licence
  * [including the GNU Public Licence.]
  */
+/* ====================================================================
+ * Copyright (c) 1998-2006 The OpenSSL Project.  All rights reserved.
+ *
+ * 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 above 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 acknowledgment:
+ *    "This product includes software developed by the OpenSSL Project
+ *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
+ *
+ * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
+ *    endorse or promote products derived from this software without
+ *    prior written permission. For written permission, please contact
+ *    openssl-core@openssl.org.
+ *
+ * 5. Products derived from this software may not be called "OpenSSL"
+ *    nor may "OpenSSL" appear in their names without prior written
+ *    permission of the OpenSSL Project.
+ *
+ * 6. Redistributions of any form whatsoever must retain the following
+ *    acknowledgment:
+ *    "This product includes software developed by the OpenSSL Project
+ *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
+ * EXPRESSED 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 OpenSSL PROJECT OR
+ * ITS 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.
+ * ====================================================================
+ *
+ * This product includes cryptographic software written by Eric Young
+ * (eay@cryptsoft.com).  This product includes software written by Tim
+ * Hudson (tjh@cryptsoft.com).
+ *
+ */
 
 /*
  * Details about Montgomery multiplication algorithms can be found at
@@ -69,11 +122,50 @@
 
 #define MONT_WORD /* use the faster word-based algorithm */
 
+#if defined(MONT_WORD) && defined(OPENSSL_BN_ASM_MONT) && (BN_BITS2<=32)
+/* This condition means we have a specific non-default build:
+ * In the 0.9.8 branch, OPENSSL_BN_ASM_MONT is normally not set for any
+ * BN_BITS2<=32 platform; an explicit "enable-montasm" is required.
+ * I.e., if we are here, the user intentionally deviates from the
+ * normal stable build to get better Montgomery performance from
+ * the 0.9.9-dev backport.
+ *
+ * In this case only, we also enable BN_from_montgomery_word()
+ * (another non-stable feature from 0.9.9-dev).
+ */
+#define MONT_FROM_WORD___NON_DEFAULT_0_9_8_BUILD
+#endif
+
+#ifdef MONT_FROM_WORD___NON_DEFAULT_0_9_8_BUILD
+static int BN_from_montgomery_word(BIGNUM *ret, BIGNUM *r, BN_MONT_CTX *mont);
+#endif
+
+
+
 int BN_mod_mul_montgomery(BIGNUM *r, const BIGNUM *a, const BIGNUM *b,
                           BN_MONT_CTX *mont, BN_CTX *ctx)
         {
         BIGNUM *tmp;
         int ret=0;
+#if defined(OPENSSL_BN_ASM_MONT) && defined(MONT_WORD)
+        int num = mont->N.top;
+
+        if (num>1 && a->top==num && b->top==num)
+                {
+                if (bn_wexpand(r,num) == NULL) return(0);
+#if 0 /* for OpenSSL 0.9.9 mont->n0 */
+                if (bn_mul_mont(r->d,a->d,b->d,mont->N.d,mont->n0,num))
+#else
+                if (bn_mul_mont(r->d,a->d,b->d,mont->N.d,&mont->n0,num))
+#endif
+                        {
+                        r->neg = a->neg^b->neg;
+                        r->top = num;
+                        bn_correct_top(r);
+                        return(1);
+                        }
+                }
+#endif
 
         BN_CTX_start(ctx);
         tmp = BN_CTX_get(ctx);
@@ -89,13 +181,162 @@ int BN_mod_mul_montgomery(BIGNUM *r, const BIGNUM *a, const BIGNUM *b,
                 if (!BN_mul(tmp,a,b,ctx)) goto err;
                 }
         /* reduce from aRR to aR */
+#ifdef MONT_FROM_WORD___NON_DEFAULT_0_9_8_BUILD
+        if (!BN_from_montgomery_word(r,tmp,mont)) goto err;
+#else
         if (!BN_from_montgomery(r,tmp,mont,ctx)) goto err;
+#endif
+        bn_check_top(r);
         ret=1;
 err:
         BN_CTX_end(ctx);
         return(ret);
         }
 
+#ifdef MONT_FROM_WORD___NON_DEFAULT_0_9_8_BUILD
+static int BN_from_montgomery_word(BIGNUM *ret, BIGNUM *r, BN_MONT_CTX *mont)
+        {
+        BIGNUM *n;
+        BN_ULONG *ap,*np,*rp,n0,v,*nrp;
+        int al,nl,max,i,x,ri;
+
+        n= &(mont->N);
+        /* mont->ri is the size of mont->N in bits (rounded up
+           to the word size) */
+        al=ri=mont->ri/BN_BITS2;
+
+        nl=n->top;
+        if ((al == 0) || (nl == 0)) { ret->top=0; return(1); }
+
+        max=(nl+al+1); /* allow for overflow (no?) XXX */
+        if (bn_wexpand(r,max) == NULL) return(0);
+
+        r->neg^=n->neg;
+        np=n->d;
+        rp=r->d;
+        nrp= &(r->d[nl]);
+
+        /* clear the top words of T */
+        for (i=r->top; i<max; i++) /* memset? XXX */
+                r->d[i]=0;
+
+        r->top=max;
+#if 0 /* for OpenSSL 0.9.9 mont->n0 */
+        n0=mont->n0[0];
+#else
+        n0=mont->n0;
+#endif
+
+#ifdef BN_COUNT
+        fprintf(stderr,"word BN_from_montgomery_word %d * %d\n",nl,nl);
+#endif
+        for (i=0; i<nl; i++)
+                {
+#ifdef __TANDEM
+                {
+                   long long t1;
+                   long long t2;
+                   long long t3;
+                   t1 = rp[0] * (n0 & 0177777);
+                   t2 = 037777600000l;
+                   t2 = n0 & t2;
+                   t3 = rp[0] & 0177777;
+                   t2 = (t3 * t2) & BN_MASK2;
+                   t1 = t1 + t2;
+                   v=bn_mul_add_words(rp,np,nl,(BN_ULONG) t1);
+                }
+#else
+                v=bn_mul_add_words(rp,np,nl,(rp[0]*n0)&BN_MASK2);
+#endif
+                nrp++;
+                rp++;
+                if (((nrp[-1]+=v)&BN_MASK2) >= v)
+                        continue;
+                else
+                        {
+                        if (((++nrp[0])&BN_MASK2) != 0) continue;
+                        if (((++nrp[1])&BN_MASK2) != 0) continue;
+                        for (x=2; (((++nrp[x])&BN_MASK2) == 0); x++) ;
+                        }
+                }
+        bn_correct_top(r);
+
+        /* mont->ri will be a multiple of the word size and below code
+         * is kind of BN_rshift(ret,r,mont->ri) equivalent */
+        if (r->top <= ri)
+                {
+                ret->top=0;
+                return(1);
+                }
+        al=r->top-ri;
+
+        if (bn_wexpand(ret,ri) == NULL) return(0);
+        x=0-(((al-ri)>>(sizeof(al)*8-1))&1);
+        ret->top=x=(ri&~x)|(al&x);      /* min(ri,al) */
+        ret->neg=r->neg;
+
+        rp=ret->d;
+        ap=&(r->d[ri]);
+
+        {
+        size_t m1,m2;
+
+        v=bn_sub_words(rp,ap,np,ri);
+        /* this ----------------^^ works even in al<ri case
+         * thanks to zealous zeroing of top of the vector in the
+         * beginning. */
+
+        /* if (al==ri && !v) || al>ri) nrp=rp; else nrp=ap; */
+        /* in other words if subtraction result is real, then
+         * trick unconditional memcpy below to perform in-place
+         * "refresh" instead of actual copy. */
+        m1=0-(size_t)(((al-ri)>>(sizeof(al)*8-1))&1);   /* al<ri */
+        m2=0-(size_t)(((ri-al)>>(sizeof(al)*8-1))&1);   /* al>ri */
+        m1|=m2;                 /* (al!=ri) */
+        m1|=(0-(size_t)v);      /* (al!=ri || v) */
+        m1&=~m2;                /* (al!=ri || v) && !al>ri */
+        nrp=(BN_ULONG *)(((size_t)rp&~m1)|((size_t)ap&m1));
+        }
+
+        /* 'i<ri' is chosen to eliminate dependency on input data, even
+         * though it results in redundant copy in al<ri case. */
+        for (i=0,ri-=4; i<ri; i+=4)
+                {
+                BN_ULONG t1,t2,t3,t4;
+                
+                t1=nrp[i+0];
+                t2=nrp[i+1];
+                t3=nrp[i+2];    ap[i+0]=0;
+                t4=nrp[i+3];    ap[i+1]=0;
+                rp[i+0]=t1;     ap[i+2]=0;
+                rp[i+1]=t2;     ap[i+3]=0;
+                rp[i+2]=t3;
+                rp[i+3]=t4;
+                }
+        for (ri+=4; i<ri; i++)
+                rp[i]=nrp[i], ap[i]=0;
+        bn_correct_top(r);
+        bn_correct_top(ret);
+        bn_check_top(ret);
+
+        return(1);
+        }
+
+int BN_from_montgomery(BIGNUM *ret, const BIGNUM *a, BN_MONT_CTX *mont,
+             BN_CTX *ctx)
+        {
+        int retn=0;
+        BIGNUM *t;
+
+        BN_CTX_start(ctx);
+        if ((t = BN_CTX_get(ctx)) && BN_copy(t,a))
+                retn = BN_from_montgomery_word(ret,t,mont);
+        BN_CTX_end(ctx);
+        return retn;
+        }
+
+#else /* !MONT_FROM_WORD___NON_DEFAULT_0_9_8_BUILD */
+
 int BN_from_montgomery(BIGNUM *ret, const BIGNUM *a, BN_MONT_CTX *mont,
              BN_CTX *ctx)
         {
@@ -171,7 +412,7 @@ int BN_from_montgomery(BIGNUM *ret, const BIGNUM *a, BN_MONT_CTX *mont,
                         for (x=2; (((++nrp[x])&BN_MASK2) == 0); x++) ;
                         }
                 }
-        bn_fix_top(r);
+        bn_correct_top(r);
         
         /* mont->ri will be a multiple of the word size and below code
          * is kind of BN_rshift(ret,r,mont->ri) equivalent */
@@ -230,6 +471,8 @@ int BN_from_montgomery(BIGNUM *ret, const BIGNUM *a, BN_MONT_CTX *mont,
                 }
         for (ri+=4; i<ri; i++)
                 rp[i]=nrp[i], ap[i]=0;
+        bn_correct_top(r);
+        bn_correct_top(ret);
 # else
         if (bn_wexpand(ret,al) == NULL) goto err;
         ret->top=al;
@@ -281,10 +524,12 @@ int BN_from_montgomery(BIGNUM *ret, const BIGNUM *a, BN_MONT_CTX *mont,
                 }
 #endif
         retn=1;
+        bn_check_top(ret);
  err:
         BN_CTX_end(ctx);
         return(retn);
         }
+#endif /* MONT_FROM_WORD___NON_DEFAULT_0_9_8_BUILD */
 
 BN_MONT_CTX *BN_MONT_CTX_new(void)
         {
@@ -304,6 +549,11 @@ void BN_MONT_CTX_init(BN_MONT_CTX *ctx)
         BN_init(&(ctx->RR));
         BN_init(&(ctx->N));
         BN_init(&(ctx->Ni));
+#if 0 /* for OpenSSL 0.9.9 mont->n0 */
+        ctx->n0[0] = ctx->n0[1] = 0;
+#else
+        ctx->n0 = 0;
+#endif
         ctx->flags=0;
         }
 
@@ -321,9 +571,11 @@ void BN_MONT_CTX_free(BN_MONT_CTX *mont)
 
 int BN_MONT_CTX_set(BN_MONT_CTX *mont, const BIGNUM *mod, BN_CTX *ctx)
         {
-        BIGNUM Ri,*R;
+        int ret = 0;
+        BIGNUM *Ri,*R;
 
-        BN_init(&Ri);
+        BN_CTX_start(ctx);
+        if((Ri = BN_CTX_get(ctx)) == NULL) goto err;
         R= &(mont->RR);                                 /* grab RR as a temp */
         if (!BN_copy(&(mont->N),mod)) goto err;         /* Set N */
         mont->N.neg = 0;
@@ -334,57 +586,99 @@ int BN_MONT_CTX_set(BN_MONT_CTX *mont, const BIGNUM *mod, BN_CTX *ctx)
                 BN_ULONG buf[2];
 
                 mont->ri=(BN_num_bits(mod)+(BN_BITS2-1))/BN_BITS2*BN_BITS2;
-                if (!(BN_zero(R))) goto err;
+                BN_zero(R);
+#if 0 /* for OpenSSL 0.9.9 mont->n0, would be "#if defined(OPENSSL_BN_ASM_MONT) && (BN_BITS2<=32)",
+         only certain BN_BITS2<=32 platforms actually need this */
+                if (!(BN_set_bit(R,2*BN_BITS2))) goto err;      /* R */
+#else
                 if (!(BN_set_bit(R,BN_BITS2))) goto err;        /* R */
+#endif
 
                 buf[0]=mod->d[0]; /* tmod = N mod word size */
                 buf[1]=0;
+
+                BN_init(&tmod);
                 tmod.d=buf;
-                tmod.top=1;
+                tmod.top = buf[0] != 0 ? 1 : 0;
                 tmod.dmax=2;
                 tmod.neg=0;
+
+#if 0 /* for OpenSSL 0.9.9 mont->n0, would be "#if defined(OPENSSL_BN_ASM_MONT) && (BN_BITS2<=32)";
+         only certain BN_BITS2<=32 platforms actually need this */
+                                                                tmod.top=0;
+                if ((buf[0] = mod->d[0]))                       tmod.top=1;
+                if ((buf[1] = mod->top>1 ? mod->d[1] : 0))      tmod.top=2;
+
+                if ((BN_mod_inverse(Ri,R,&tmod,ctx)) == NULL)
+                        goto err;
+                if (!BN_lshift(Ri,Ri,2*BN_BITS2)) goto err; /* R*Ri */
+                if (!BN_is_zero(Ri))
+                        {
+                        if (!BN_sub_word(Ri,1)) goto err;
+                        }
+                else /* if N mod word size == 1 */
+                        {
+                        if (bn_expand(Ri,(int)sizeof(BN_ULONG)*2) == NULL)
+                                goto err;
+                        /* Ri-- (mod double word size) */
+                        Ri->neg=0;
+                        Ri->d[0]=BN_MASK2;
+                        Ri->d[1]=BN_MASK2;
+                        Ri->top=2;
+                        }
+                if (!BN_div(Ri,NULL,Ri,&tmod,ctx)) goto err;
+                /* Ni = (R*Ri-1)/N,
+                 * keep only couple of least significant words: */
+                mont->n0[0] = (Ri->top > 0) ? Ri->d[0] : 0;
+                mont->n0[1] = (Ri->top > 1) ? Ri->d[1] : 0;
+#else
                                                         /* Ri = R^-1 mod N*/
-                if ((BN_mod_inverse(&Ri,R,&tmod,ctx)) == NULL)
+                if ((BN_mod_inverse(Ri,R,&tmod,ctx)) == NULL)
                         goto err;
-                if (!BN_lshift(&Ri,&Ri,BN_BITS2)) goto err; /* R*Ri */
-                if (!BN_is_zero(&Ri))
+                if (!BN_lshift(Ri,Ri,BN_BITS2)) goto err; /* R*Ri */
+                if (!BN_is_zero(Ri))
                         {
-                        if (!BN_sub_word(&Ri,1)) goto err;
+                        if (!BN_sub_word(Ri,1)) goto err;
                         }
                 else /* if N mod word size == 1 */
                         {
-                        if (!BN_set_word(&Ri,BN_MASK2)) goto err;  /* Ri-- (mod word size) */
+                        if (!BN_set_word(Ri,BN_MASK2)) goto err;  /* Ri-- (mod word size) */
                         }
-                if (!BN_div(&Ri,NULL,&Ri,&tmod,ctx)) goto err;
+                if (!BN_div(Ri,NULL,Ri,&tmod,ctx)) goto err;
                 /* Ni = (R*Ri-1)/N,
                  * keep only least significant word: */
-                mont->n0 = (Ri.top > 0) ? Ri.d[0] : 0;
-                BN_free(&Ri);
+# if 0 /* for OpenSSL 0.9.9 mont->n0 */
+                mont->n0[0] = (Ri->top > 0) ? Ri->d[0] : 0;
+                mont->n0[1] = 0;
+# else
+                mont->n0 = (Ri->top > 0) ? Ri->d[0] : 0;
+# endif
+#endif
                 }
 #else /* !MONT_WORD */
                 { /* bignum version */
                 mont->ri=BN_num_bits(&mont->N);
-                if (!BN_zero(R)) goto err;
+                BN_zero(R);
                 if (!BN_set_bit(R,mont->ri)) goto err;  /* R = 2^ri */
                                                         /* Ri = R^-1 mod N*/
-                if ((BN_mod_inverse(&Ri,R,&mont->N,ctx)) == NULL)
+                if ((BN_mod_inverse(Ri,R,&mont->N,ctx)) == NULL)
                         goto err;
-                if (!BN_lshift(&Ri,&Ri,mont->ri)) goto err; /* R*Ri */
-                if (!BN_sub_word(&Ri,1)) goto err;
+                if (!BN_lshift(Ri,Ri,mont->ri)) goto err; /* R*Ri */
+                if (!BN_sub_word(Ri,1)) goto err;
                                                         /* Ni = (R*Ri-1) / N */
-                if (!BN_div(&(mont->Ni),NULL,&Ri,&mont->N,ctx)) goto err;
-                BN_free(&Ri);
+                if (!BN_div(&(mont->Ni),NULL,Ri,&mont->N,ctx)) goto err;
                 }
 #endif
 
         /* setup RR for conversions */
-        if (!BN_zero(&(mont->RR))) goto err;
+        BN_zero(&(mont->RR));
         if (!BN_set_bit(&(mont->RR),mont->ri*2)) goto err;
         if (!BN_mod(&(mont->RR),&(mont->RR),&(mont->N),ctx)) goto err;
 
-        return(1);
+        ret = 1;
 err:
-        return(0);
+        BN_CTX_end(ctx);
+        return ret;
         }
 
 BN_MONT_CTX *BN_MONT_CTX_copy(BN_MONT_CTX *to, BN_MONT_CTX *from)
@@ -395,27 +689,44 @@ BN_MONT_CTX *BN_MONT_CTX_copy(BN_MONT_CTX *to, BN_MONT_CTX *from)
         if (!BN_copy(&(to->N),&(from->N))) return NULL;
         if (!BN_copy(&(to->Ni),&(from->Ni))) return NULL;
         to->ri=from->ri;
+#if 0 /* for OpenSSL 0.9.9 mont->n0 */
+        to->n0[0]=from->n0[0];
+        to->n0[1]=from->n0[1];
+#else
         to->n0=from->n0;
+#endif
         return(to);
         }
 
 BN_MONT_CTX *BN_MONT_CTX_set_locked(BN_MONT_CTX **pmont, int lock,
                                         const BIGNUM *mod, BN_CTX *ctx)
         {
-        if (*pmont)
-                return *pmont;
-        CRYPTO_w_lock(lock);
+        int got_write_lock = 0;
+        BN_MONT_CTX *ret;
+
+        CRYPTO_r_lock(lock);
         if (!*pmont)
                 {
-                *pmont = BN_MONT_CTX_new();
-                if (*pmont && !BN_MONT_CTX_set(*pmont, mod, ctx))
+                CRYPTO_r_unlock(lock);
+                CRYPTO_w_lock(lock);
+                got_write_lock = 1;
+
+                if (!*pmont)
                         {
-                        BN_MONT_CTX_free(*pmont);
-                        *pmont = NULL;
+                        ret = BN_MONT_CTX_new();
+                        if (ret && !BN_MONT_CTX_set(ret, mod, ctx))
+                                BN_MONT_CTX_free(ret);
+                        else
+                                *pmont = ret;
                         }
                 }
-        CRYPTO_w_unlock(lock);
-        return *pmont;
-        }
+        
+        ret = *pmont;
+        
+        if (got_write_lock)
+                CRYPTO_w_unlock(lock);
+        else
+                CRYPTO_r_unlock(lock);
                 
-
+        return ret;
+        }