New function BN_bntest_rand() to detect more BN library bugs.

The bn_cmp_part_words bug was only caught in the BN_mod_mul() test,
not in the BN_mul() test, so apparently the choice of parameters in
some cases is bad.

diff --git a/crypto/bn/bn.h b/crypto/bn/bn.h
index b55ac956428799195e93bed7ce0a7d55feff43a7..3d5c91adb94b9127d3644c4063a1a5f545eb4913 100644 (file)
--- a/crypto/bn/bn.h
+++ b/crypto/bn/bn.h
@@ -495,6 +495,8 @@ void bn_dump1(FILE *o, const char *a, const BN_ULONG *b,int n);
 # define bn_dump(a,b)
 #endif
 
+int BN_bntest_rand(BIGNUM *rnd, int bits, int top,int bottom);
+
 /* BEGIN ERROR CODES */
 /* The following lines are auto generated by the script mkerr.pl. Any changes
  * made after this point may be overwritten when the script is next run.

diff --git a/crypto/bn/bn_rand.c b/crypto/bn/bn_rand.c
index 21ecbc04ed0aa53e88a22a8f0e5b9935b4704b13..bab4510345090374089fd7d66d1313b88a29b6ed 100644 (file)
--- a/crypto/bn/bn_rand.c
+++ b/crypto/bn/bn_rand.c
@@ -100,6 +100,27 @@ static int bnrand(int pseudorand, BIGNUM *rnd, int bits, int top, int bottom)
                        goto err;
                }
 
+#if 1
+       if (pseudorand == 2)
+               {
+               /* generate patterns that are more likely to trigger BN
+                  library bugs */
+               int i;
+               unsigned char c;
+
+               for (i = 0; i < bytes; i++)
+                       {
+                       RAND_pseudo_bytes(&c, 1);
+                       if (c >= 128 && i > 0)
+                               buf[i] = buf[i-1];
+                       else if (c < 42)
+                               buf[i] = 0;
+                       else if (c < 84)
+                               buf[i] = 255;
+                       }
+               }
+#endif
+
        if (top)
                {
                if (bit == 0)
@@ -140,3 +161,10 @@ int     BN_pseudo_rand(BIGNUM *rnd, int bits, int top, int bottom)
        {
        return bnrand(1, rnd, bits, top, bottom);
        }
+
+#if 1
+int     BN_bntest_rand(BIGNUM *rnd, int bits, int top, int bottom)
+       {
+       return bnrand(2, rnd, bits, top, bottom);
+       }
+#endif

diff --git a/crypto/bn/bntest.c b/crypto/bn/bntest.c
index 2df0d29b1a3bf3cb45cb9ebd29451a3c518cad48..7c9e5b419617921979e99bbfa412a9cee71a53e9 100644 (file)
--- a/crypto/bn/bntest.c
+++ b/crypto/bn/bntest.c
@@ -124,9 +124,7 @@ int main(int argc, char *argv[])
 
        results = 0;
 
-       RAND_seed(rnd_seed, sizeof rnd_seed); /* or BN_rand may fail, and we don't
-                                              * even check its return value
-                                              * (which we should) */
+       RAND_seed(rnd_seed, sizeof rnd_seed); /* or BN_generate_prime may fail */
 
        argc--;
        argv++;
@@ -263,10 +261,10 @@ int test_add(BIO *bp)
        BN_init(&b);
        BN_init(&c);
 
-       BN_rand(&a,512,0,0);
+       BN_bntest_rand(&a,512,0,0);
        for (i=0; i<num0; i++)
                {
-               BN_rand(&b,450+i,0,0);
+               BN_bntest_rand(&b,450+i,0,0);
                a.neg=rand_neg();
                b.neg=rand_neg();
                if (bp == NULL)
@@ -315,14 +313,14 @@ int test_sub(BIO *bp)
                {
                if (i < num1)
                        {
-                       BN_rand(&a,512,0,0);
+                       BN_bntest_rand(&a,512,0,0);
                        BN_copy(&b,&a);
                        if (BN_set_bit(&a,i)==0) return(0);
                        BN_add_word(&b,i);
                        }
                else
                        {
-                       BN_rand(&b,400+i-num1,0,0);
+                       BN_bntest_rand(&b,400+i-num1,0,0);
                        a.neg=rand_neg();
                        b.neg=rand_neg();
                        }
@@ -372,13 +370,13 @@ int test_div(BIO *bp, BN_CTX *ctx)
                {
                if (i < num1)
                        {
-                       BN_rand(&a,400,0,0);
+                       BN_bntest_rand(&a,400,0,0);
                        BN_copy(&b,&a);
                        BN_lshift(&a,&a,i);
                        BN_add_word(&a,i);
                        }
                else
-                       BN_rand(&b,50+3*(i-num1),0,0);
+                       BN_bntest_rand(&b,50+3*(i-num1),0,0);
                a.neg=rand_neg();
                b.neg=rand_neg();
                if (bp == NULL)
@@ -442,13 +440,13 @@ int test_div_recp(BIO *bp, BN_CTX *ctx)
                {
                if (i < num1)
                        {
-                       BN_rand(&a,400,0,0);
+                       BN_bntest_rand(&a,400,0,0);
                        BN_copy(&b,&a);
                        BN_lshift(&a,&a,i);
                        BN_add_word(&a,i);
                        }
                else
-                       BN_rand(&b,50+3*(i-num1),0,0);
+                       BN_bntest_rand(&b,50+3*(i-num1),0,0);
                a.neg=rand_neg();
                b.neg=rand_neg();
                BN_RECP_CTX_set(&recp,&b,ctx);
@@ -519,11 +517,11 @@ int test_mul(BIO *bp)
                {
                if (i <= num1)
                        {
-                       BN_rand(&a,100,0,0);
-                       BN_rand(&b,100,0,0);
+                       BN_bntest_rand(&a,100,0,0);
+                       BN_bntest_rand(&b,100,0,0);
                        }
                else
-                       BN_rand(&b,i-num1,0,0);
+                       BN_bntest_rand(&b,i-num1,0,0);
                a.neg=rand_neg();
                b.neg=rand_neg();
                if (bp == NULL)
@@ -572,7 +570,7 @@ int test_sqr(BIO *bp, BN_CTX *ctx)
 
        for (i=0; i<num0; i++)
                {
-               BN_rand(&a,40+i*10,0,0);
+               BN_bntest_rand(&a,40+i*10,0,0);
                a.neg=rand_neg();
                if (bp == NULL)
                        for (j=0; j<100; j++)
@@ -623,15 +621,15 @@ int test_mont(BIO *bp, BN_CTX *ctx)
 
        mont=BN_MONT_CTX_new();
 
-       BN_rand(&a,100,0,0); /**/
-       BN_rand(&b,100,0,0); /**/
+       BN_bntest_rand(&a,100,0,0); /**/
+       BN_bntest_rand(&b,100,0,0); /**/
        for (i=0; i<num2; i++)
                {
                int bits = (200*(i+1))/num2;
 
                if (bits == 0)
                        continue;
-               BN_rand(&n,bits,0,1);
+               BN_bntest_rand(&n,bits,0,1);
                BN_MONT_CTX_set(mont,&n,ctx);
 
                BN_nnmod(&a,&a,&n,ctx);
@@ -696,10 +694,10 @@ int test_mod(BIO *bp, BN_CTX *ctx)
        d=BN_new();
        e=BN_new();
 
-       BN_rand(a,1024,0,0); /**/
+       BN_bntest_rand(a,1024,0,0); /**/
        for (i=0; i<num0; i++)
                {
-               BN_rand(b,450+i*10,0,0); /**/
+               BN_bntest_rand(b,450+i*10,0,0); /**/
                a->neg=rand_neg();
                b->neg=rand_neg();
                if (bp == NULL)
@@ -745,11 +743,11 @@ int test_mod_mul(BIO *bp, BN_CTX *ctx)
        d=BN_new();
        e=BN_new();
 
-       BN_rand(c,1024,0,0); /**/
+       BN_bntest_rand(c,1024,0,0); /**/
        for (i=0; i<num0; i++)
                {
-               BN_rand(a,475+i*10,0,0); /**/
-               BN_rand(b,425+i*11,0,0); /**/
+               BN_bntest_rand(a,475+i*10,0,0); /**/
+               BN_bntest_rand(b,425+i*11,0,0); /**/
                a->neg=rand_neg();
                b->neg=rand_neg();
        /*      if (bp == NULL)
@@ -818,11 +816,11 @@ int test_mod_exp(BIO *bp, BN_CTX *ctx)
        d=BN_new();
        e=BN_new();
 
-       BN_rand(c,30,0,1); /* must be odd for montgomery */
+       BN_bntest_rand(c,30,0,1); /* must be odd for montgomery */
        for (i=0; i<num2; i++)
                {
-               BN_rand(a,20+i*5,0,0); /**/
-               BN_rand(b,2+i,0,0); /**/
+               BN_bntest_rand(a,20+i*5,0,0); /**/
+               BN_bntest_rand(b,2+i,0,0); /**/
 
                if (!BN_mod_exp(d,a,b,c,ctx))
                        return(00);
@@ -872,8 +870,8 @@ int test_exp(BIO *bp, BN_CTX *ctx)
 
        for (i=0; i<num2; i++)
                {
-               BN_rand(a,20+i*5,0,0); /**/
-               BN_rand(b,2+i,0,0); /**/
+               BN_bntest_rand(a,20+i*5,0,0); /**/
+               BN_bntest_rand(b,2+i,0,0); /**/
 
                if (!BN_exp(d,a,b,ctx))
                        return(00);
@@ -949,7 +947,7 @@ int test_kron(BIO *bp, BN_CTX *ctx)
 
        for (i = 0; i < num0; i++)
                {
-               if (!BN_rand(a, 512, 0, 0)) goto err;
+               if (!BN_bntest_rand(a, 512, 0, 0)) goto err;
                a->neg = rand_neg();
 
                /* t := (b-1)/2  (note that b is odd) */
@@ -1034,10 +1032,10 @@ int test_sqrt(BIO *bp, BN_CTX *ctx)
                        {
                        /* construct 'a' such that it is a square modulo p,
                         * but in general not a proper square and not reduced modulo p */
-                       if (!BN_rand(r, 256, 0, 3)) goto err;
+                       if (!BN_bntest_rand(r, 256, 0, 3)) goto err;
                        if (!BN_nnmod(r, r, p, ctx)) goto err;
                        if (!BN_mod_sqr(r, r, p, ctx)) goto err;
-                       if (!BN_rand(a, 256, 0, 3)) goto err;
+                       if (!BN_bntest_rand(a, 256, 0, 3)) goto err;
                        if (!BN_nnmod(a, a, p, ctx)) goto err;
                        if (!BN_mod_sqr(a, a, p, ctx)) goto err;
                        if (!BN_mul(a, a, r, ctx)) goto err;
@@ -1089,7 +1087,7 @@ int test_lshift(BIO *bp,BN_CTX *ctx,BIGNUM *a_)
        else
            {
            a=BN_new();
-           BN_rand(a,200,0,0); /**/
+           BN_bntest_rand(a,200,0,0); /**/
            a->neg=rand_neg();
            }
        for (i=0; i<num0; i++)
@@ -1141,7 +1139,7 @@ int test_lshift1(BIO *bp)
        b=BN_new();
        c=BN_new();
 
-       BN_rand(a,200,0,0); /**/
+       BN_bntest_rand(a,200,0,0); /**/
        a->neg=rand_neg();
        for (i=0; i<num0; i++)
                {
@@ -1185,7 +1183,7 @@ int test_rshift(BIO *bp,BN_CTX *ctx)
        e=BN_new();
        BN_one(c);
 
-       BN_rand(a,200,0,0); /**/
+       BN_bntest_rand(a,200,0,0); /**/
        a->neg=rand_neg();
        for (i=0; i<num0; i++)
                {
@@ -1228,7 +1226,7 @@ int test_rshift1(BIO *bp)
        b=BN_new();
        c=BN_new();
 
-       BN_rand(a,200,0,0); /**/
+       BN_bntest_rand(a,200,0,0); /**/
        a->neg=rand_neg();
        for (i=0; i<num0; i++)
                {