test/exptest.c:161: error: BUFFER_OVERRUN_L3
  Offset: [8, +oo] (⇐ [8, +oo] + [0, +oo]) Size: [0, 8388607] by call to `BN_mod_exp_mont`.
Showing all 23 steps of the trace


test/exptest.c:149:5: Call
147.       RAND_bytes(&c, 1);
148.       c = (c % BN_BITS) - BN_BITS2;
149.       BN_rand(a, NUM_BITS + c, BN_RAND_TOP_ONE, BN_RAND_BOTTOM_ANY);
           ^
150.   
151.       RAND_bytes(&c, 1);

crypto/bn/bn_rand.c:97:1: Parameter `*rnd->d`
  95.   }
  96.   
  97. > int BN_rand(BIGNUM *rnd, int bits, int top, int bottom)
  98.   {
  99.       return bnrand(NORMAL, rnd, bits, top, bottom);

crypto/bn/bn_rand.c:99:12: Call
  97.   int BN_rand(BIGNUM *rnd, int bits, int top, int bottom)
  98.   {
  99.       return bnrand(NORMAL, rnd, bits, top, bottom);
                    ^
  100.   }
  101.   

crypto/bn/bn_rand.c:21:1: Parameter `*rnd->d`
    19.   } BNRAND_FLAG;
    20.   
    21. > static int bnrand(BNRAND_FLAG flag, BIGNUM *rnd, int bits, int top, int bottom)
    22.   {
    23.       unsigned char *buf = NULL;

test/exptest.c:161:13: Call
159.       if (!TEST_true(BN_mod(a, a, m, ctx))
160.           || !TEST_true(BN_mod(b, b, m, ctx))
161.           || !TEST_true(BN_mod_exp_mont(r_mont, a, b, m, ctx, NULL))
                   ^
162.           || !TEST_true(BN_mod_exp_recp(r_recp, a, b, m, ctx))
163.           || !TEST_true(BN_mod_exp_simple(r_simple, a, b, m, ctx))

crypto/bn/bn_exp.c:296:1: Parameter `*a->d`
  294.   }
  295.   
  296. > int BN_mod_exp_mont(BIGNUM *rr, const BIGNUM *a, const BIGNUM *p,
  297.                       const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *in_mont)
  298.   {

crypto/bn/bn_exp.c:364:10: Call
  362.           goto err;
  363.       }
  364.       if (!bn_to_mont_fixed_top(val[0], aa, mont, ctx))
                  ^
  365.           goto err;               /* 1 */
  366.   

crypto/bn/bn_mont.c:210:1: Parameter `*a->d`
    208.   }
    209.   
    210. > int bn_to_mont_fixed_top(BIGNUM *r, const BIGNUM *a, BN_MONT_CTX *mont,
    211.                            BN_CTX *ctx)
    212.   {

crypto/bn/bn_mont.c:213:12: Call
    211.                            BN_CTX *ctx)
    212.   {
    213.       return bn_mul_mont_fixed_top(r, a, &(mont->RR), mont, ctx);
                      ^
    214.   }
    215.   

crypto/bn/bn_mont.c:37:1: Parameter `*a->d`
      35.   }
      36.   
      37. > int bn_mul_mont_fixed_top(BIGNUM *r, const BIGNUM *a, const BIGNUM *b,
      38.                             BN_MONT_CTX *mont, BN_CTX *ctx)
      39.   {

crypto/bn/bn_mont.c:70:14: Call
      68.               goto err;
      69.       } else {
      70.           if (!BN_mul(tmp, a, b, ctx))
                         ^
      71.               goto err;
      72.       }

crypto/bn/bn_mul.c:497:1: Parameter `*a->d`
        495.   #endif                          /* BN_RECURSION */
        496.   
        497. > int BN_mul(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, BN_CTX *ctx)
        498.   {
        499.       int ret = 0;

crypto/bn/bn_mul.c:577:17: Call
        575.                   if (bn_wexpand(rr, k * 4) == NULL)
        576.                       goto err;
        577.                   bn_mul_part_recursive(rr->d, a->d, b->d,
                               ^
        578.                                         j, al - j, bl - j, t->d);
        579.               } else {            /* al <= j || bl <= j */

crypto/bn/bn_mul.c:322:1: Parameter `n`
          320.    */
          321.   /* tnX may not be negative but less than n */
          322. > void bn_mul_part_recursive(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n,
          323.                              int tna, int tnb, BN_ULONG *t)
          324.   {

crypto/bn/bn_mul.c:335:10: Call
          333.   
          334.       /* r=(a[0]-a[1])*(b[1]-b[0]) */
          335.       c1 = bn_cmp_part_words(a, &(a[n]), tna, n - tna);
                          ^
          336.       c2 = bn_cmp_part_words(&(b[n]), b, tnb, tnb - n);
          337.       neg = 0;

crypto/bn/bn_lib.c:707:1: Parameter `cl`
            705.    */
            706.   
            707. > int bn_cmp_part_words(const BN_ULONG *a, const BN_ULONG *b, int cl, int dl)
            708.   {
            709.       int n, i;

crypto/bn/bn_lib.c:724:12: Call
            722.           }
            723.       }
            724.       return bn_cmp_words(a, b, cl);
                              ^
            725.   }
            726.   

crypto/bn/bn_lib.c:680:1: <Offset trace>
678.   }
679.   
680. > int bn_cmp_words(const BN_ULONG *a, const BN_ULONG *b, int n)
681.   {
682.       int i;

crypto/bn/bn_lib.c:680:1: Parameter `n`
              678.   }
              679.   
              680. > int bn_cmp_words(const BN_ULONG *a, const BN_ULONG *b, int n)
              681.   {
              682.       int i;

crypto/bn/bn_lib.c:689:10: Assignment
              687.       if (aa != bb)
              688.           return ((aa > bb) ? 1 : -1);
              689.       for (i = n - 2; i >= 0; i--) {
                              ^
              690.           aa = a[i];
              691.           bb = b[i];

crypto/bn/bn_lib.c:680:1: <Length trace>
678.   }
679.   
680. > int bn_cmp_words(const BN_ULONG *a, const BN_ULONG *b, int n)
681.   {
682.       int i;

crypto/bn/bn_lib.c:680:1: Parameter `*b`
              678.   }
              679.   
              680. > int bn_cmp_words(const BN_ULONG *a, const BN_ULONG *b, int n)
              681.   {
              682.       int i;

crypto/bn/bn_lib.c:691:14: Array access: Offset: [8, +oo] (⇐ [8, +oo] + [0, +oo]) Size: [0, 8388607] by call to `BN_mod_exp_mont` 
              689.       for (i = n - 2; i >= 0; i--) {
              690.           aa = a[i];
              691.           bb = b[i];
                                  ^
              692.           if (aa != bb)
              693.               return ((aa > bb) ? 1 : -1);

int bn_cmp_words(const BN_ULONG *a, const BN_ULONG *b, int n)
{
    int i;
    BN_ULONG aa, bb;
    aa = a[n - 1];
    bb = b[n - 1];
    if (aa != bb)
        return ((aa > bb) ? 1 : -1);
    for (i = n - 2; i >= 0; i--) {
        aa = a[i];
        bb = b[i];
        if (aa != bb)
            return ((aa > bb) ? 1 : -1);
    }
    return 0;
}
['static int test_mod_exp(int round)\n{\n    BN_CTX *ctx;\n    unsigned char c;\n    int ret = 0;\n    BIGNUM *r_mont = NULL;\n    BIGNUM *r_mont_const = NULL;\n    BIGNUM *r_recp = NULL;\n    BIGNUM *r_simple = NULL;\n    BIGNUM *a = NULL;\n    BIGNUM *b = NULL;\n    BIGNUM *m = NULL;\n    if (!TEST_ptr(ctx = BN_CTX_new()))\n        goto err;\n    if (!TEST_ptr(r_mont = BN_new())\n        || !TEST_ptr(r_mont_const = BN_new())\n        || !TEST_ptr(r_recp = BN_new())\n        || !TEST_ptr(r_simple = BN_new())\n        || !TEST_ptr(a = BN_new())\n        || !TEST_ptr(b = BN_new())\n        || !TEST_ptr(m = BN_new()))\n        goto err;\n    RAND_bytes(&c, 1);\n    c = (c % BN_BITS) - BN_BITS2;\n    BN_rand(a, NUM_BITS + c, BN_RAND_TOP_ONE, BN_RAND_BOTTOM_ANY);\n    RAND_bytes(&c, 1);\n    c = (c % BN_BITS) - BN_BITS2;\n    BN_rand(b, NUM_BITS + c, BN_RAND_TOP_ONE, BN_RAND_BOTTOM_ANY);\n    RAND_bytes(&c, 1);\n    c = (c % BN_BITS) - BN_BITS2;\n    BN_rand(m, NUM_BITS + c, BN_RAND_TOP_ONE, BN_RAND_BOTTOM_ODD);\n    if (!TEST_true(BN_mod(a, a, m, ctx))\n        || !TEST_true(BN_mod(b, b, m, ctx))\n        || !TEST_true(BN_mod_exp_mont(r_mont, a, b, m, ctx, NULL))\n        || !TEST_true(BN_mod_exp_recp(r_recp, a, b, m, ctx))\n        || !TEST_true(BN_mod_exp_simple(r_simple, a, b, m, ctx))\n        || !TEST_true(BN_mod_exp_mont_consttime(r_mont_const, a, b, m, ctx, NULL)))\n        goto err;\n    if (!TEST_BN_eq(r_simple, r_mont)\n        || !TEST_BN_eq(r_simple, r_recp)\n        || !TEST_BN_eq(r_simple, r_mont_const)) {\n        if (BN_cmp(r_simple, r_mont) != 0)\n            TEST_info("simple and mont results differ");\n        if (BN_cmp(r_simple, r_mont_const) != 0)\n            TEST_info("simple and mont const time results differ");\n        if (BN_cmp(r_simple, r_recp) != 0)\n            TEST_info("simple and recp results differ");\n        BN_print_var(a);\n        BN_print_var(b);\n        BN_print_var(m);\n        BN_print_var(r_simple);\n        BN_print_var(r_recp);\n        BN_print_var(r_mont);\n        BN_print_var(r_mont_const);\n        goto err;\n    }\n    ret = 1;\n err:\n    BN_free(r_mont);\n    BN_free(r_mont_const);\n    BN_free(r_recp);\n    BN_free(r_simple);\n    BN_free(a);\n    BN_free(b);\n    BN_free(m);\n    BN_CTX_free(ctx);\n    return ret;\n}', 'int BN_rand(BIGNUM *rnd, int bits, int top, int bottom)\n{\n    return bnrand(NORMAL, rnd, bits, top, bottom);\n}', 'static int bnrand(BNRAND_FLAG flag, BIGNUM *rnd, int bits, int top, int bottom)\n{\n    unsigned char *buf = NULL;\n    int b, ret = 0, bit, bytes, mask;\n    if (bits == 0) {\n        if (top != BN_RAND_TOP_ANY || bottom != BN_RAND_BOTTOM_ANY)\n            goto toosmall;\n        BN_zero(rnd);\n        return 1;\n    }\n    if (bits < 0 || (bits == 1 && top > 0))\n        goto toosmall;\n    bytes = (bits + 7) / 8;\n    bit = (bits - 1) % 8;\n    mask = 0xff << (bit + 1);\n    buf = OPENSSL_malloc(bytes);\n    if (buf == NULL) {\n        BNerr(BN_F_BNRAND, ERR_R_MALLOC_FAILURE);\n        goto err;\n    }\n    b = flag == NORMAL ? RAND_bytes(buf, bytes) : RAND_priv_bytes(buf, bytes);\n    if (b <= 0)\n        goto err;\n    if (flag == TESTING) {\n        int i;\n        unsigned char c;\n        for (i = 0; i < bytes; i++) {\n            if (RAND_bytes(&c, 1) <= 0)\n                goto err;\n            if (c >= 128 && i > 0)\n                buf[i] = buf[i - 1];\n            else if (c < 42)\n                buf[i] = 0;\n            else if (c < 84)\n                buf[i] = 255;\n        }\n    }\n    if (top >= 0) {\n        if (top) {\n            if (bit == 0) {\n                buf[0] = 1;\n                buf[1] |= 0x80;\n            } else {\n                buf[0] |= (3 << (bit - 1));\n            }\n        } else {\n            buf[0] |= (1 << bit);\n        }\n    }\n    buf[0] &= ~mask;\n    if (bottom)\n        buf[bytes - 1] |= 1;\n    if (!BN_bin2bn(buf, bytes, rnd))\n        goto err;\n    ret = 1;\n err:\n    OPENSSL_clear_free(buf, bytes);\n    bn_check_top(rnd);\n    return ret;\ntoosmall:\n    BNerr(BN_F_BNRAND, BN_R_BITS_TOO_SMALL);\n    return 0;\n}', 'int BN_mod_exp_mont(BIGNUM *rr, const BIGNUM *a, const BIGNUM *p,\n                    const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *in_mont)\n{\n    int i, j, bits, ret = 0, wstart, wend, window, wvalue;\n    int start = 1;\n    BIGNUM *d, *r;\n    const BIGNUM *aa;\n    BIGNUM *val[TABLE_SIZE];\n    BN_MONT_CTX *mont = NULL;\n    if (BN_get_flags(p, BN_FLG_CONSTTIME) != 0\n            || BN_get_flags(a, BN_FLG_CONSTTIME) != 0\n            || BN_get_flags(m, BN_FLG_CONSTTIME) != 0) {\n        return BN_mod_exp_mont_consttime(rr, a, p, m, ctx, in_mont);\n    }\n    bn_check_top(a);\n    bn_check_top(p);\n    bn_check_top(m);\n    if (!BN_is_odd(m)) {\n        BNerr(BN_F_BN_MOD_EXP_MONT, BN_R_CALLED_WITH_EVEN_MODULUS);\n        return 0;\n    }\n    bits = BN_num_bits(p);\n    if (bits == 0) {\n        if (BN_abs_is_word(m, 1)) {\n            ret = 1;\n            BN_zero(rr);\n        } else {\n            ret = BN_one(rr);\n        }\n        return ret;\n    }\n    BN_CTX_start(ctx);\n    d = BN_CTX_get(ctx);\n    r = BN_CTX_get(ctx);\n    val[0] = BN_CTX_get(ctx);\n    if (val[0] == NULL)\n        goto err;\n    if (in_mont != NULL)\n        mont = in_mont;\n    else {\n        if ((mont = BN_MONT_CTX_new()) == NULL)\n            goto err;\n        if (!BN_MONT_CTX_set(mont, m, ctx))\n            goto err;\n    }\n    if (a->neg || BN_ucmp(a, m) >= 0) {\n        if (!BN_nnmod(val[0], a, m, ctx))\n            goto err;\n        aa = val[0];\n    } else\n        aa = a;\n    if (BN_is_zero(aa)) {\n        BN_zero(rr);\n        ret = 1;\n        goto err;\n    }\n    if (!bn_to_mont_fixed_top(val[0], aa, mont, ctx))\n        goto err;\n    window = BN_window_bits_for_exponent_size(bits);\n    if (window > 1) {\n        if (!bn_mul_mont_fixed_top(d, val[0], val[0], mont, ctx))\n            goto err;\n        j = 1 << (window - 1);\n        for (i = 1; i < j; i++) {\n            if (((val[i] = BN_CTX_get(ctx)) == NULL) ||\n                !bn_mul_mont_fixed_top(val[i], val[i - 1], d, mont, ctx))\n                goto err;\n        }\n    }\n    start = 1;\n    wvalue = 0;\n    wstart = bits - 1;\n    wend = 0;\n#if 1\n    j = m->top;\n    if (m->d[j - 1] & (((BN_ULONG)1) << (BN_BITS2 - 1))) {\n        if (bn_wexpand(r, j) == NULL)\n            goto err;\n        r->d[0] = (0 - m->d[0]) & BN_MASK2;\n        for (i = 1; i < j; i++)\n            r->d[i] = (~m->d[i]) & BN_MASK2;\n        r->top = j;\n        r->flags |= BN_FLG_FIXED_TOP;\n    } else\n#endif\n    if (!bn_to_mont_fixed_top(r, BN_value_one(), mont, ctx))\n        goto err;\n    for (;;) {\n        if (BN_is_bit_set(p, wstart) == 0) {\n            if (!start) {\n                if (!bn_mul_mont_fixed_top(r, r, r, mont, ctx))\n                    goto err;\n            }\n            if (wstart == 0)\n                break;\n            wstart--;\n            continue;\n        }\n        j = wstart;\n        wvalue = 1;\n        wend = 0;\n        for (i = 1; i < window; i++) {\n            if (wstart - i < 0)\n                break;\n            if (BN_is_bit_set(p, wstart - i)) {\n                wvalue <<= (i - wend);\n                wvalue |= 1;\n                wend = i;\n            }\n        }\n        j = wend + 1;\n        if (!start)\n            for (i = 0; i < j; i++) {\n                if (!bn_mul_mont_fixed_top(r, r, r, mont, ctx))\n                    goto err;\n            }\n        if (!bn_mul_mont_fixed_top(r, r, val[wvalue >> 1], mont, ctx))\n            goto err;\n        wstart -= wend + 1;\n        wvalue = 0;\n        start = 0;\n        if (wstart < 0)\n            break;\n    }\n#if defined(SPARC_T4_MONT)\n    if (OPENSSL_sparcv9cap_P[0] & (SPARCV9_VIS3 | SPARCV9_PREFER_FPU)) {\n        j = mont->N.top;\n        val[0]->d[0] = 1;\n        for (i = 1; i < j; i++)\n            val[0]->d[i] = 0;\n        val[0]->top = j;\n        if (!BN_mod_mul_montgomery(rr, r, val[0], mont, ctx))\n            goto err;\n    } else\n#endif\n    if (!BN_from_montgomery(rr, r, mont, ctx))\n        goto err;\n    ret = 1;\n err:\n    if (in_mont == NULL)\n        BN_MONT_CTX_free(mont);\n    BN_CTX_end(ctx);\n    bn_check_top(rr);\n    return ret;\n}', 'int bn_to_mont_fixed_top(BIGNUM *r, const BIGNUM *a, BN_MONT_CTX *mont,\n                         BN_CTX *ctx)\n{\n    return bn_mul_mont_fixed_top(r, a, &(mont->RR), mont, ctx);\n}', 'int bn_mul_mont_fixed_top(BIGNUM *r, const BIGNUM *a, const BIGNUM *b,\n                          BN_MONT_CTX *mont, BN_CTX *ctx)\n{\n    BIGNUM *tmp;\n    int ret = 0;\n    int num = mont->N.top;\n#if defined(OPENSSL_BN_ASM_MONT) && defined(MONT_WORD)\n    if (num > 1 && a->top == num && b->top == num) {\n        if (bn_wexpand(r, num) == NULL)\n            return 0;\n        if (bn_mul_mont(r->d, a->d, b->d, mont->N.d, mont->n0, num)) {\n            r->neg = a->neg ^ b->neg;\n            r->top = num;\n            r->flags |= BN_FLG_FIXED_TOP;\n            return 1;\n        }\n    }\n#endif\n    if ((a->top + b->top) > 2 * num)\n        return 0;\n    BN_CTX_start(ctx);\n    tmp = BN_CTX_get(ctx);\n    if (tmp == NULL)\n        goto err;\n    bn_check_top(tmp);\n    if (a == b) {\n        if (!BN_sqr(tmp, a, ctx))\n            goto err;\n    } else {\n        if (!BN_mul(tmp, a, b, ctx))\n            goto err;\n    }\n#ifdef MONT_WORD\n    if (!bn_from_montgomery_word(r, tmp, mont))\n        goto err;\n#else\n    if (!BN_from_montgomery(r, tmp, mont, ctx))\n        goto err;\n#endif\n    ret = 1;\n err:\n    BN_CTX_end(ctx);\n    return ret;\n}', 'int BN_mul(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, BN_CTX *ctx)\n{\n    int ret = 0;\n    int top, al, bl;\n    BIGNUM *rr;\n#if defined(BN_MUL_COMBA) || defined(BN_RECURSION)\n    int i;\n#endif\n#ifdef BN_RECURSION\n    BIGNUM *t = NULL;\n    int j = 0, k;\n#endif\n    bn_check_top(a);\n    bn_check_top(b);\n    bn_check_top(r);\n    al = a->top;\n    bl = b->top;\n    if ((al == 0) || (bl == 0)) {\n        BN_zero(r);\n        return 1;\n    }\n    top = al + bl;\n    BN_CTX_start(ctx);\n    if ((r == a) || (r == b)) {\n        if ((rr = BN_CTX_get(ctx)) == NULL)\n            goto err;\n    } else\n        rr = r;\n#if defined(BN_MUL_COMBA) || defined(BN_RECURSION)\n    i = al - bl;\n#endif\n#ifdef BN_MUL_COMBA\n    if (i == 0) {\n# if 0\n        if (al == 4) {\n            if (bn_wexpand(rr, 8) == NULL)\n                goto err;\n            rr->top = 8;\n            bn_mul_comba4(rr->d, a->d, b->d);\n            goto end;\n        }\n# endif\n        if (al == 8) {\n            if (bn_wexpand(rr, 16) == NULL)\n                goto err;\n            rr->top = 16;\n            bn_mul_comba8(rr->d, a->d, b->d);\n            goto end;\n        }\n    }\n#endif\n#ifdef BN_RECURSION\n    if ((al >= BN_MULL_SIZE_NORMAL) && (bl >= BN_MULL_SIZE_NORMAL)) {\n        if (i >= -1 && i <= 1) {\n            if (i >= 0) {\n                j = BN_num_bits_word((BN_ULONG)al);\n            }\n            if (i == -1) {\n                j = BN_num_bits_word((BN_ULONG)bl);\n            }\n            j = 1 << (j - 1);\n            assert(j <= al || j <= bl);\n            k = j + j;\n            t = BN_CTX_get(ctx);\n            if (t == NULL)\n                goto err;\n            if (al > j || bl > j) {\n                if (bn_wexpand(t, k * 4) == NULL)\n                    goto err;\n                if (bn_wexpand(rr, k * 4) == NULL)\n                    goto err;\n                bn_mul_part_recursive(rr->d, a->d, b->d,\n                                      j, al - j, bl - j, t->d);\n            } else {\n                if (bn_wexpand(t, k * 2) == NULL)\n                    goto err;\n                if (bn_wexpand(rr, k * 2) == NULL)\n                    goto err;\n                bn_mul_recursive(rr->d, a->d, b->d, j, al - j, bl - j, t->d);\n            }\n            rr->top = top;\n            goto end;\n        }\n    }\n#endif\n    if (bn_wexpand(rr, top) == NULL)\n        goto err;\n    rr->top = top;\n    bn_mul_normal(rr->d, a->d, al, b->d, bl);\n#if defined(BN_MUL_COMBA) || defined(BN_RECURSION)\n end:\n#endif\n    rr->neg = a->neg ^ b->neg;\n    bn_correct_top(rr);\n    if (r != rr && BN_copy(r, rr) == NULL)\n        goto err;\n    ret = 1;\n err:\n    bn_check_top(r);\n    BN_CTX_end(ctx);\n    return ret;\n}', 'void bn_mul_part_recursive(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n,\n                           int tna, int tnb, BN_ULONG *t)\n{\n    int i, j, n2 = n * 2;\n    int c1, c2, neg;\n    BN_ULONG ln, lo, *p;\n    if (n < 8) {\n        bn_mul_normal(r, a, n + tna, b, n + tnb);\n        return;\n    }\n    c1 = bn_cmp_part_words(a, &(a[n]), tna, n - tna);\n    c2 = bn_cmp_part_words(&(b[n]), b, tnb, tnb - n);\n    neg = 0;\n    switch (c1 * 3 + c2) {\n    case -4:\n        bn_sub_part_words(t, &(a[n]), a, tna, tna - n);\n        bn_sub_part_words(&(t[n]), b, &(b[n]), tnb, n - tnb);\n        break;\n    case -3:\n    case -2:\n        bn_sub_part_words(t, &(a[n]), a, tna, tna - n);\n        bn_sub_part_words(&(t[n]), &(b[n]), b, tnb, tnb - n);\n        neg = 1;\n        break;\n    case -1:\n    case 0:\n    case 1:\n    case 2:\n        bn_sub_part_words(t, a, &(a[n]), tna, n - tna);\n        bn_sub_part_words(&(t[n]), b, &(b[n]), tnb, n - tnb);\n        neg = 1;\n        break;\n    case 3:\n    case 4:\n        bn_sub_part_words(t, a, &(a[n]), tna, n - tna);\n        bn_sub_part_words(&(t[n]), &(b[n]), b, tnb, tnb - n);\n        break;\n    }\n# if 0\n    if (n == 4) {\n        bn_mul_comba4(&(t[n2]), t, &(t[n]));\n        bn_mul_comba4(r, a, b);\n        bn_mul_normal(&(r[n2]), &(a[n]), tn, &(b[n]), tn);\n        memset(&r[n2 + tn * 2], 0, sizeof(*r) * (n2 - tn * 2));\n    } else\n# endif\n    if (n == 8) {\n        bn_mul_comba8(&(t[n2]), t, &(t[n]));\n        bn_mul_comba8(r, a, b);\n        bn_mul_normal(&(r[n2]), &(a[n]), tna, &(b[n]), tnb);\n        memset(&r[n2 + tna + tnb], 0, sizeof(*r) * (n2 - tna - tnb));\n    } else {\n        p = &(t[n2 * 2]);\n        bn_mul_recursive(&(t[n2]), t, &(t[n]), n, 0, 0, p);\n        bn_mul_recursive(r, a, b, n, 0, 0, p);\n        i = n / 2;\n        if (tna > tnb)\n            j = tna - i;\n        else\n            j = tnb - i;\n        if (j == 0) {\n            bn_mul_recursive(&(r[n2]), &(a[n]), &(b[n]),\n                             i, tna - i, tnb - i, p);\n            memset(&r[n2 + i * 2], 0, sizeof(*r) * (n2 - i * 2));\n        } else if (j > 0) {\n            bn_mul_part_recursive(&(r[n2]), &(a[n]), &(b[n]),\n                                  i, tna - i, tnb - i, p);\n            memset(&(r[n2 + tna + tnb]), 0,\n                   sizeof(BN_ULONG) * (n2 - tna - tnb));\n        } else {\n            memset(&r[n2], 0, sizeof(*r) * n2);\n            if (tna < BN_MUL_RECURSIVE_SIZE_NORMAL\n                && tnb < BN_MUL_RECURSIVE_SIZE_NORMAL) {\n                bn_mul_normal(&(r[n2]), &(a[n]), tna, &(b[n]), tnb);\n            } else {\n                for (;;) {\n                    i /= 2;\n                    if (i < tna || i < tnb) {\n                        bn_mul_part_recursive(&(r[n2]),\n                                              &(a[n]), &(b[n]),\n                                              i, tna - i, tnb - i, p);\n                        break;\n                    } else if (i == tna || i == tnb) {\n                        bn_mul_recursive(&(r[n2]),\n                                         &(a[n]), &(b[n]),\n                                         i, tna - i, tnb - i, p);\n                        break;\n                    }\n                }\n            }\n        }\n    }\n    c1 = (int)(bn_add_words(t, r, &(r[n2]), n2));\n    if (neg) {\n        c1 -= (int)(bn_sub_words(&(t[n2]), t, &(t[n2]), n2));\n    } else {\n        c1 += (int)(bn_add_words(&(t[n2]), &(t[n2]), t, n2));\n    }\n    c1 += (int)(bn_add_words(&(r[n]), &(r[n]), &(t[n2]), n2));\n    if (c1) {\n        p = &(r[n + n2]);\n        lo = *p;\n        ln = (lo + c1) & BN_MASK2;\n        *p = ln;\n        if (ln < (BN_ULONG)c1) {\n            do {\n                p++;\n                lo = *p;\n                ln = (lo + 1) & BN_MASK2;\n                *p = ln;\n            } while (ln == 0);\n        }\n    }\n}', 'int bn_cmp_part_words(const BN_ULONG *a, const BN_ULONG *b, int cl, int dl)\n{\n    int n, i;\n    n = cl - 1;\n    if (dl < 0) {\n        for (i = dl; i < 0; i++) {\n            if (b[n - i] != 0)\n                return -1;\n        }\n    }\n    if (dl > 0) {\n        for (i = dl; i > 0; i--) {\n            if (a[n + i] != 0)\n                return 1;\n        }\n    }\n    return bn_cmp_words(a, b, cl);\n}', 'int bn_cmp_words(const BN_ULONG *a, const BN_ULONG *b, int n)\n{\n    int i;\n    BN_ULONG aa, bb;\n    aa = a[n - 1];\n    bb = b[n - 1];\n    if (aa != bb)\n        return ((aa > bb) ? 1 : -1);\n    for (i = n - 2; i >= 0; i--) {\n        aa = a[i];\n        bb = b[i];\n        if (aa != bb)\n            return ((aa > bb) ? 1 : -1);\n    }\n    return 0;\n}']