Adjust various bignum functions to use BN_CTX for variables instead of
[openssl.git] / crypto / bn / bn_exp.c
index c11e5af..d6bb2b4 100644 (file)
@@ -231,9 +231,10 @@ int BN_mod_exp_recp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
                    const BIGNUM *m, BN_CTX *ctx)
        {
        int i,j,bits,ret=0,wstart,wend,window,wvalue;
-       int start=1,ts=0;
+       int start=1;
        BIGNUM *aa;
-       BIGNUM val[TABLE_SIZE];
+       /* Table of variables obtained from 'ctx' */
+       BIGNUM *val[TABLE_SIZE];
        BN_RECP_CTX recp;
 
        bits=BN_num_bits(p);
@@ -245,7 +246,9 @@ int BN_mod_exp_recp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
                }
 
        BN_CTX_start(ctx);
-       if ((aa = BN_CTX_get(ctx)) == NULL) goto err;
+       aa = BN_CTX_get(ctx);
+       val[0] = BN_CTX_get(ctx);
+       if(!aa || !val[0]) goto err;
 
        BN_RECP_CTX_init(&recp);
        if (m->neg)
@@ -260,11 +263,8 @@ int BN_mod_exp_recp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
                if (BN_RECP_CTX_set(&recp,m,ctx) <= 0) goto err;
                }
 
-       BN_init(&(val[0]));
-       ts=1;
-
-       if (!BN_nnmod(&(val[0]),a,m,ctx)) goto err;             /* 1 */
-       if (BN_is_zero(&(val[0])))
+       if (!BN_nnmod(val[0],a,m,ctx)) goto err;                /* 1 */
+       if (BN_is_zero(val[0]))
                {
                BN_zero(r);
                ret = 1;
@@ -274,16 +274,16 @@ int BN_mod_exp_recp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
        window = BN_window_bits_for_exponent_size(bits);
        if (window > 1)
                {
-               if (!BN_mod_mul_reciprocal(aa,&(val[0]),&(val[0]),&recp,ctx))
+               if (!BN_mod_mul_reciprocal(aa,val[0],val[0],&recp,ctx))
                        goto err;                               /* 2 */
                j=1<<(window-1);
                for (i=1; i<j; i++)
                        {
-                       BN_init(&val[i]);
-                       if (!BN_mod_mul_reciprocal(&(val[i]),&(val[i-1]),aa,&recp,ctx))
+                       if(((val[i] = BN_CTX_get(ctx)) == NULL) ||
+                                       !BN_mod_mul_reciprocal(val[i],val[i-1],
+                                               aa,&recp,ctx))
                                goto err;
                        }
-               ts=i;
                }
                
        start=1;        /* This is used to avoid multiplication etc
@@ -335,7 +335,7 @@ int BN_mod_exp_recp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
                                }
                
                /* wvalue will be an odd number < 2^window */
-               if (!BN_mod_mul_reciprocal(r,r,&(val[wvalue>>1]),&recp,ctx))
+               if (!BN_mod_mul_reciprocal(r,r,val[wvalue>>1],&recp,ctx))
                        goto err;
 
                /* move the 'window' down further */
@@ -347,8 +347,6 @@ int BN_mod_exp_recp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
        ret=1;
 err:
        BN_CTX_end(ctx);
-       for (i=0; i<ts; i++)
-               BN_clear_free(&(val[i]));
        BN_RECP_CTX_free(&recp);
        bn_check_top(r);
        return(ret);
@@ -359,11 +357,11 @@ int BN_mod_exp_mont(BIGNUM *rr, const BIGNUM *a, const BIGNUM *p,
                    const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *in_mont)
        {
        int i,j,bits,ret=0,wstart,wend,window,wvalue;
-       int start=1,ts=0;
+       int start=1;
        BIGNUM *d,*r;
        const BIGNUM *aa;
-       /* TODO: BN_CTX??? */
-       BIGNUM val[TABLE_SIZE];
+       /* Table of variables obtained from 'ctx' */
+       BIGNUM *val[TABLE_SIZE];
        BN_MONT_CTX *mont=NULL;
 
        bn_check_top(a);
@@ -385,7 +383,8 @@ int BN_mod_exp_mont(BIGNUM *rr, const BIGNUM *a, const BIGNUM *p,
        BN_CTX_start(ctx);
        d = BN_CTX_get(ctx);
        r = BN_CTX_get(ctx);
-       if (d == NULL || r == NULL) goto err;
+       val[0] = BN_CTX_get(ctx);
+       if (!d || !r || !val[0]) goto err;
 
        /* If this is not done, things will break in the montgomery
         * part */
@@ -398,13 +397,11 @@ int BN_mod_exp_mont(BIGNUM *rr, const BIGNUM *a, const BIGNUM *p,
                if (!BN_MONT_CTX_set(mont,m,ctx)) goto err;
                }
 
-       BN_init(&val[0]);
-       ts=1;
        if (a->neg || BN_ucmp(a,m) >= 0)
                {
-               if (!BN_nnmod(&(val[0]),a,m,ctx))
+               if (!BN_nnmod(val[0],a,m,ctx))
                        goto err;
-               aa= &(val[0]);
+               aa= val[0];
                }
        else
                aa=a;
@@ -414,20 +411,20 @@ int BN_mod_exp_mont(BIGNUM *rr, const BIGNUM *a, const BIGNUM *p,
                ret = 1;
                goto err;
                }
-       if (!BN_to_montgomery(&(val[0]),aa,mont,ctx)) goto err; /* 1 */
+       if (!BN_to_montgomery(val[0],aa,mont,ctx)) goto err; /* 1 */
 
        window = BN_window_bits_for_exponent_size(bits);
        if (window > 1)
                {
-               if (!BN_mod_mul_montgomery(d,&(val[0]),&(val[0]),mont,ctx)) goto err; /* 2 */
+               if (!BN_mod_mul_montgomery(d,val[0],val[0],mont,ctx)) goto err; /* 2 */
                j=1<<(window-1);
                for (i=1; i<j; i++)
                        {
-                       BN_init(&(val[i]));
-                       if (!BN_mod_mul_montgomery(&(val[i]),&(val[i-1]),d,mont,ctx))
+                       if(((val[i] = BN_CTX_get(ctx)) == NULL) ||
+                                       !BN_mod_mul_montgomery(val[i],val[i-1],
+                                               d,mont,ctx))
                                goto err;
                        }
-               ts=i;
                }
 
        start=1;        /* This is used to avoid multiplication etc
@@ -480,7 +477,7 @@ int BN_mod_exp_mont(BIGNUM *rr, const BIGNUM *a, const BIGNUM *p,
                                }
                
                /* wvalue will be an odd number < 2^window */
-               if (!BN_mod_mul_montgomery(r,r,&(val[wvalue>>1]),mont,ctx))
+               if (!BN_mod_mul_montgomery(r,r,val[wvalue>>1],mont,ctx))
                        goto err;
 
                /* move the 'window' down further */
@@ -494,8 +491,6 @@ int BN_mod_exp_mont(BIGNUM *rr, const BIGNUM *a, const BIGNUM *p,
 err:
        if ((in_mont == NULL) && (mont != NULL)) BN_MONT_CTX_free(mont);
        BN_CTX_end(ctx);
-       for (i=0; i<ts; i++)
-               BN_clear_free(&(val[i]));
        bn_check_top(rr);
        return(ret);
        }
@@ -647,11 +642,11 @@ err:
 int BN_mod_exp_simple(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
                const BIGNUM *m, BN_CTX *ctx)
        {
-       int i,j,bits,ret=0,wstart,wend,window,wvalue,ts=0;
+       int i,j,bits,ret=0,wstart,wend,window,wvalue;
        int start=1;
        BIGNUM *d;
-       /* TODO: BN_CTX?? */
-       BIGNUM val[TABLE_SIZE];
+       /* Table of variables obtained from 'ctx' */
+       BIGNUM *val[TABLE_SIZE];
 
        bits=BN_num_bits(p);
 
@@ -662,12 +657,12 @@ int BN_mod_exp_simple(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
                }
 
        BN_CTX_start(ctx);
-       if ((d = BN_CTX_get(ctx)) == NULL) goto err;
+       d = BN_CTX_get(ctx);
+       val[0] = BN_CTX_get(ctx);
+       if(!d || !val[0]) goto err;
 
-       BN_init(&(val[0]));
-       ts=1;
-       if (!BN_nnmod(&(val[0]),a,m,ctx)) goto err;             /* 1 */
-       if (BN_is_zero(&(val[0])))
+       if (!BN_nnmod(val[0],a,m,ctx)) goto err;                /* 1 */
+       if (BN_is_zero(val[0]))
                {
                BN_zero(r);
                ret = 1;
@@ -677,16 +672,15 @@ int BN_mod_exp_simple(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
        window = BN_window_bits_for_exponent_size(bits);
        if (window > 1)
                {
-               if (!BN_mod_mul(d,&(val[0]),&(val[0]),m,ctx))
+               if (!BN_mod_mul(d,val[0],val[0],m,ctx))
                        goto err;                               /* 2 */
                j=1<<(window-1);
                for (i=1; i<j; i++)
                        {
-                       BN_init(&(val[i]));
-                       if (!BN_mod_mul(&(val[i]),&(val[i-1]),d,m,ctx))
+                       if(((val[i] = BN_CTX_get(ctx)) == NULL) ||
+                                       !BN_mod_mul(val[i],val[i-1],d,m,ctx))
                                goto err;
                        }
-               ts=i;
                }
 
        start=1;        /* This is used to avoid multiplication etc
@@ -738,7 +732,7 @@ int BN_mod_exp_simple(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
                                }
                
                /* wvalue will be an odd number < 2^window */
-               if (!BN_mod_mul(r,r,&(val[wvalue>>1]),m,ctx))
+               if (!BN_mod_mul(r,r,val[wvalue>>1],m,ctx))
                        goto err;
 
                /* move the 'window' down further */
@@ -750,8 +744,6 @@ int BN_mod_exp_simple(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
        ret=1;
 err:
        BN_CTX_end(ctx);
-       for (i=0; i<ts; i++)
-               BN_clear_free(&(val[i]));
        bn_check_top(r);
        return(ret);
        }