crypto/dsa/dsa_ossl.c:384: error: INTEGER_OVERFLOW_L2
  ([0, +oo] - 1):unsigned32 by call to `BN_mod_inverse`.
Showing all 20 steps of the trace


crypto/dsa/dsa_ossl.c:384:10: Call
382.        * Calculate W = inv(S) mod Q save W in u2
383.        */
384.       if ((BN_mod_inverse(u2, sig->s, dsa->q, ctx)) == NULL)
                ^
385.           goto err;
386.   

crypto/bn/bn_gcd.c:226:1: Parameter `ctx->stack.depth`
  224.                                           BN_CTX *ctx);
  225.   
  226. > BIGNUM *BN_mod_inverse(BIGNUM *in,
  227.                          const BIGNUM *a, const BIGNUM *n, BN_CTX *ctx)
  228.   {

crypto/bn/bn_gcd.c:231:10: Call
  229.       BIGNUM *rv;
  230.       int noinv;
  231.       rv = int_bn_mod_inverse(in, a, n, ctx, &noinv);
                  ^
  232.       if (noinv)
  233.           BNerr(BN_F_BN_MOD_INVERSE, BN_R_NO_INVERSE);

crypto/bn/bn_gcd.c:237:1: Parameter `ctx->stack.depth`
    235.   }
    236.   
    237. > BIGNUM *int_bn_mod_inverse(BIGNUM *in,
    238.                              const BIGNUM *a, const BIGNUM *n, BN_CTX *ctx,
    239.                              int *pnoinv)

crypto/bn/bn_gcd.c:250:16: Call
    248.       if ((BN_get_flags(a, BN_FLG_CONSTTIME) != 0)
    249.           || (BN_get_flags(n, BN_FLG_CONSTTIME) != 0)) {
    250.           return BN_mod_inverse_no_branch(in, a, n, ctx);
                          ^
    251.       }
    252.   

crypto/bn/bn_gcd.c:557:1: Parameter `ctx->stack.depth`
      555.    * not contain branches that may leak sensitive information.
      556.    */
      557. > static BIGNUM *BN_mod_inverse_no_branch(BIGNUM *in,
      558.                                           const BIGNUM *a, const BIGNUM *n,
      559.                                           BN_CTX *ctx)

crypto/bn/bn_gcd.c:570:5: Call
      568.       bn_check_top(n);
      569.   
      570.       BN_CTX_start(ctx);
                 ^
      571.       A = BN_CTX_get(ctx);
      572.       B = BN_CTX_get(ctx);

crypto/bn/bn_ctx.c:253:1: Parameter `ctx->stack.depth`
        251.   }
        252.   
        253. > void BN_CTX_start(BN_CTX *ctx)
        254.   {
        255.       CTXDBG_ENTRY("BN_CTX_start", ctx);

crypto/bn/bn_gcd.c:603:14: Call
      601.           pB = &local_B;
      602.           BN_with_flags(pB, B, BN_FLG_CONSTTIME);
      603.           if (!BN_nnmod(B, pB, A, ctx))
                          ^
      604.               goto err;
      605.       }

crypto/bn/bn_mod.c:127:1: Parameter `ctx->stack.depth`
        125.   #endif
        126.   
        127. > int BN_nnmod(BIGNUM *r, const BIGNUM *m, const BIGNUM *d, BN_CTX *ctx)
        128.   {
        129.       /*

crypto/bn/bn_mod.c:134:11: Call
        132.        */
        133.   
        134.       if (!(BN_mod(r, m, d, ctx)))
                         ^
        135.           return 0;
        136.       if (!r->neg)

crypto/bn/bn_div.c:189:1: Parameter `ctx->stack.depth`
          187.    * If 'dv' or 'rm' is NULL, the respective value is not returned.
          188.    */
          189. > int BN_div(BIGNUM *dv, BIGNUM *rm, const BIGNUM *num, const BIGNUM *divisor,
          190.              BN_CTX *ctx)
          191.   {

crypto/bn/bn_div.c:242:5: Call
          240.       }
          241.   
          242.       BN_CTX_start(ctx);
                     ^
          243.       tmp = BN_CTX_get(ctx);
          244.       snum = BN_CTX_get(ctx);

crypto/bn/bn_ctx.c:253:1: Parameter `ctx->stack.depth`
            251.   }
            252.   
            253. > void BN_CTX_start(BN_CTX *ctx)
            254.   {
            255.       CTXDBG_ENTRY("BN_CTX_start", ctx);

crypto/bn/bn_div.c:469:5: Call
          467.       if (no_branch)
          468.           bn_correct_top(res);
          469.       BN_CTX_end(ctx);
                     ^
          470.       return (1);
          471.    err:

crypto/bn/bn_ctx.c:267:1: Parameter `ctx->stack.depth`
            265.   }
            266.   
            267. > void BN_CTX_end(BN_CTX *ctx)
            268.   {
            269.       CTXDBG_ENTRY("BN_CTX_end", ctx);

crypto/bn/bn_ctx.c:273:27: Call
            271.           ctx->err_stack--;
            272.       else {
            273.           unsigned int fp = BN_STACK_pop(&ctx->stack);
                                             ^
            274.           /* Does this stack frame have anything to release? */
            275.           if (fp < ctx->used)

crypto/bn/bn_ctx.c:351:1: <LHS trace>
349.   }
350.   
351. > static unsigned int BN_STACK_pop(BN_STACK *st)
352.   {
353.       return st->indexes[--(st->depth)];

crypto/bn/bn_ctx.c:351:1: Parameter `st->depth`
              349.   }
              350.   
              351. > static unsigned int BN_STACK_pop(BN_STACK *st)
              352.   {
              353.       return st->indexes[--(st->depth)];

crypto/bn/bn_ctx.c:353:12: Binary operation: ([0, +oo] - 1):unsigned32 by call to `BN_mod_inverse` 
              351.   static unsigned int BN_STACK_pop(BN_STACK *st)
              352.   {
              353.       return st->indexes[--(st->depth)];
                                ^
              354.   }
              355.   

static unsigned int BN_STACK_pop(BN_STACK *st)
{
    return st->indexes[--(st->depth)];
}
['static int dsa_do_verify(const unsigned char *dgst, int dgst_len,\n                         DSA_SIG *sig, DSA *dsa)\n{\n    BN_CTX *ctx;\n    BIGNUM *u1, *u2, *t1;\n    BN_MONT_CTX *mont = NULL;\n    int ret = -1, i;\n    if (!dsa->p || !dsa->q || !dsa->g) {\n        DSAerr(DSA_F_DSA_DO_VERIFY, DSA_R_MISSING_PARAMETERS);\n        return -1;\n    }\n    i = BN_num_bits(dsa->q);\n    if (i != 160 && i != 224 && i != 256) {\n        DSAerr(DSA_F_DSA_DO_VERIFY, DSA_R_BAD_Q_VALUE);\n        return -1;\n    }\n    if (BN_num_bits(dsa->p) > OPENSSL_DSA_MAX_MODULUS_BITS) {\n        DSAerr(DSA_F_DSA_DO_VERIFY, DSA_R_MODULUS_TOO_LARGE);\n        return -1;\n    }\n    u1 = BN_new();\n    u2 = BN_new();\n    t1 = BN_new();\n    ctx = BN_CTX_new();\n    if (!u1 || !u2 || !t1 || !ctx)\n        goto err;\n    if (BN_is_zero(sig->r) || BN_is_negative(sig->r) ||\n        BN_ucmp(sig->r, dsa->q) >= 0) {\n        ret = 0;\n        goto err;\n    }\n    if (BN_is_zero(sig->s) || BN_is_negative(sig->s) ||\n        BN_ucmp(sig->s, dsa->q) >= 0) {\n        ret = 0;\n        goto err;\n    }\n    if ((BN_mod_inverse(u2, sig->s, dsa->q, ctx)) == NULL)\n        goto err;\n    if (dgst_len > (i >> 3))\n        dgst_len = (i >> 3);\n    if (BN_bin2bn(dgst, dgst_len, u1) == NULL)\n        goto err;\n    if (!BN_mod_mul(u1, u1, u2, dsa->q, ctx))\n        goto err;\n    if (!BN_mod_mul(u2, sig->r, u2, dsa->q, ctx))\n        goto err;\n    if (dsa->flags & DSA_FLAG_CACHE_MONT_P) {\n        mont = BN_MONT_CTX_set_locked(&dsa->method_mont_p,\n                                      CRYPTO_LOCK_DSA, dsa->p, ctx);\n        if (!mont)\n            goto err;\n    }\n    DSA_MOD_EXP(goto err, dsa, t1, dsa->g, u1, dsa->pub_key, u2, dsa->p, ctx,\n                mont);\n    if (!BN_mod(u1, t1, dsa->q, ctx))\n        goto err;\n    ret = (BN_ucmp(u1, sig->r) == 0);\n err:\n    if (ret < 0)\n        DSAerr(DSA_F_DSA_DO_VERIFY, ERR_R_BN_LIB);\n    if (ctx != NULL)\n        BN_CTX_free(ctx);\n    if (u1)\n        BN_free(u1);\n    if (u2)\n        BN_free(u2);\n    if (t1)\n        BN_free(t1);\n    return (ret);\n}', 'BIGNUM *BN_mod_inverse(BIGNUM *in,\n                       const BIGNUM *a, const BIGNUM *n, BN_CTX *ctx)\n{\n    BIGNUM *rv;\n    int noinv;\n    rv = int_bn_mod_inverse(in, a, n, ctx, &noinv);\n    if (noinv)\n        BNerr(BN_F_BN_MOD_INVERSE, BN_R_NO_INVERSE);\n    return rv;\n}', 'BIGNUM *int_bn_mod_inverse(BIGNUM *in,\n                           const BIGNUM *a, const BIGNUM *n, BN_CTX *ctx,\n                           int *pnoinv)\n{\n    BIGNUM *A, *B, *X, *Y, *M, *D, *T, *R = NULL;\n    BIGNUM *ret = NULL;\n    int sign;\n    if (pnoinv)\n        *pnoinv = 0;\n    if ((BN_get_flags(a, BN_FLG_CONSTTIME) != 0)\n        || (BN_get_flags(n, BN_FLG_CONSTTIME) != 0)) {\n        return BN_mod_inverse_no_branch(in, a, n, ctx);\n    }\n    bn_check_top(a);\n    bn_check_top(n);\n    BN_CTX_start(ctx);\n    A = BN_CTX_get(ctx);\n    B = BN_CTX_get(ctx);\n    X = BN_CTX_get(ctx);\n    D = BN_CTX_get(ctx);\n    M = BN_CTX_get(ctx);\n    Y = BN_CTX_get(ctx);\n    T = BN_CTX_get(ctx);\n    if (T == NULL)\n        goto err;\n    if (in == NULL)\n        R = BN_new();\n    else\n        R = in;\n    if (R == NULL)\n        goto err;\n    BN_one(X);\n    BN_zero(Y);\n    if (BN_copy(B, a) == NULL)\n        goto err;\n    if (BN_copy(A, n) == NULL)\n        goto err;\n    A->neg = 0;\n    if (B->neg || (BN_ucmp(B, A) >= 0)) {\n        if (!BN_nnmod(B, B, A, ctx))\n            goto err;\n    }\n    sign = -1;\n    if (BN_is_odd(n) && (BN_num_bits(n) <= (BN_BITS <= 32 ? 450 : 2048))) {\n        int shift;\n        while (!BN_is_zero(B)) {\n            shift = 0;\n            while (!BN_is_bit_set(B, shift)) {\n                shift++;\n                if (BN_is_odd(X)) {\n                    if (!BN_uadd(X, X, n))\n                        goto err;\n                }\n                if (!BN_rshift1(X, X))\n                    goto err;\n            }\n            if (shift > 0) {\n                if (!BN_rshift(B, B, shift))\n                    goto err;\n            }\n            shift = 0;\n            while (!BN_is_bit_set(A, shift)) {\n                shift++;\n                if (BN_is_odd(Y)) {\n                    if (!BN_uadd(Y, Y, n))\n                        goto err;\n                }\n                if (!BN_rshift1(Y, Y))\n                    goto err;\n            }\n            if (shift > 0) {\n                if (!BN_rshift(A, A, shift))\n                    goto err;\n            }\n            if (BN_ucmp(B, A) >= 0) {\n                if (!BN_uadd(X, X, Y))\n                    goto err;\n                if (!BN_usub(B, B, A))\n                    goto err;\n            } else {\n                if (!BN_uadd(Y, Y, X))\n                    goto err;\n                if (!BN_usub(A, A, B))\n                    goto err;\n            }\n        }\n    } else {\n        while (!BN_is_zero(B)) {\n            BIGNUM *tmp;\n            if (BN_num_bits(A) == BN_num_bits(B)) {\n                if (!BN_one(D))\n                    goto err;\n                if (!BN_sub(M, A, B))\n                    goto err;\n            } else if (BN_num_bits(A) == BN_num_bits(B) + 1) {\n                if (!BN_lshift1(T, B))\n                    goto err;\n                if (BN_ucmp(A, T) < 0) {\n                    if (!BN_one(D))\n                        goto err;\n                    if (!BN_sub(M, A, B))\n                        goto err;\n                } else {\n                    if (!BN_sub(M, A, T))\n                        goto err;\n                    if (!BN_add(D, T, B))\n                        goto err;\n                    if (BN_ucmp(A, D) < 0) {\n                        if (!BN_set_word(D, 2))\n                            goto err;\n                    } else {\n                        if (!BN_set_word(D, 3))\n                            goto err;\n                        if (!BN_sub(M, M, B))\n                            goto err;\n                    }\n                }\n            } else {\n                if (!BN_div(D, M, A, B, ctx))\n                    goto err;\n            }\n            tmp = A;\n            A = B;\n            B = M;\n            if (BN_is_one(D)) {\n                if (!BN_add(tmp, X, Y))\n                    goto err;\n            } else {\n                if (BN_is_word(D, 2)) {\n                    if (!BN_lshift1(tmp, X))\n                        goto err;\n                } else if (BN_is_word(D, 4)) {\n                    if (!BN_lshift(tmp, X, 2))\n                        goto err;\n                } else if (D->top == 1) {\n                    if (!BN_copy(tmp, X))\n                        goto err;\n                    if (!BN_mul_word(tmp, D->d[0]))\n                        goto err;\n                } else {\n                    if (!BN_mul(tmp, D, X, ctx))\n                        goto err;\n                }\n                if (!BN_add(tmp, tmp, Y))\n                    goto err;\n            }\n            M = Y;\n            Y = X;\n            X = tmp;\n            sign = -sign;\n        }\n    }\n    if (sign < 0) {\n        if (!BN_sub(Y, n, Y))\n            goto err;\n    }\n    if (BN_is_one(A)) {\n        if (!Y->neg && BN_ucmp(Y, n) < 0) {\n            if (!BN_copy(R, Y))\n                goto err;\n        } else {\n            if (!BN_nnmod(R, Y, n, ctx))\n                goto err;\n        }\n    } else {\n        if (pnoinv)\n            *pnoinv = 1;\n        goto err;\n    }\n    ret = R;\n err:\n    if ((ret == NULL) && (in == NULL))\n        BN_free(R);\n    BN_CTX_end(ctx);\n    bn_check_top(ret);\n    return (ret);\n}', 'static BIGNUM *BN_mod_inverse_no_branch(BIGNUM *in,\n                                        const BIGNUM *a, const BIGNUM *n,\n                                        BN_CTX *ctx)\n{\n    BIGNUM *A, *B, *X, *Y, *M, *D, *T, *R = NULL;\n    BIGNUM local_A, local_B;\n    BIGNUM *pA, *pB;\n    BIGNUM *ret = NULL;\n    int sign;\n    bn_check_top(a);\n    bn_check_top(n);\n    BN_CTX_start(ctx);\n    A = BN_CTX_get(ctx);\n    B = BN_CTX_get(ctx);\n    X = BN_CTX_get(ctx);\n    D = BN_CTX_get(ctx);\n    M = BN_CTX_get(ctx);\n    Y = BN_CTX_get(ctx);\n    T = BN_CTX_get(ctx);\n    if (T == NULL)\n        goto err;\n    if (in == NULL)\n        R = BN_new();\n    else\n        R = in;\n    if (R == NULL)\n        goto err;\n    BN_one(X);\n    BN_zero(Y);\n    if (BN_copy(B, a) == NULL)\n        goto err;\n    if (BN_copy(A, n) == NULL)\n        goto err;\n    A->neg = 0;\n    if (B->neg || (BN_ucmp(B, A) >= 0)) {\n        pB = &local_B;\n        BN_with_flags(pB, B, BN_FLG_CONSTTIME);\n        if (!BN_nnmod(B, pB, A, ctx))\n            goto err;\n    }\n    sign = -1;\n    while (!BN_is_zero(B)) {\n        BIGNUM *tmp;\n        pA = &local_A;\n        BN_with_flags(pA, A, BN_FLG_CONSTTIME);\n        if (!BN_div(D, M, pA, B, ctx))\n            goto err;\n        tmp = A;\n        A = B;\n        B = M;\n        if (!BN_mul(tmp, D, X, ctx))\n            goto err;\n        if (!BN_add(tmp, tmp, Y))\n            goto err;\n        M = Y;\n        Y = X;\n        X = tmp;\n        sign = -sign;\n    }\n    if (sign < 0) {\n        if (!BN_sub(Y, n, Y))\n            goto err;\n    }\n    if (BN_is_one(A)) {\n        if (!Y->neg && BN_ucmp(Y, n) < 0) {\n            if (!BN_copy(R, Y))\n                goto err;\n        } else {\n            if (!BN_nnmod(R, Y, n, ctx))\n                goto err;\n        }\n    } else {\n        BNerr(BN_F_BN_MOD_INVERSE_NO_BRANCH, BN_R_NO_INVERSE);\n        goto err;\n    }\n    ret = R;\n err:\n    if ((ret == NULL) && (in == NULL))\n        BN_free(R);\n    BN_CTX_end(ctx);\n    bn_check_top(ret);\n    return (ret);\n}', 'void BN_CTX_start(BN_CTX *ctx)\n{\n    CTXDBG_ENTRY("BN_CTX_start", ctx);\n    if (ctx->err_stack || ctx->too_many)\n        ctx->err_stack++;\n    else if (!BN_STACK_push(&ctx->stack, ctx->used)) {\n        BNerr(BN_F_BN_CTX_START, BN_R_TOO_MANY_TEMPORARY_VARIABLES);\n        ctx->err_stack++;\n    }\n    CTXDBG_EXIT(ctx);\n}', 'int BN_nnmod(BIGNUM *r, const BIGNUM *m, const BIGNUM *d, BN_CTX *ctx)\n{\n    if (!(BN_mod(r, m, d, ctx)))\n        return 0;\n    if (!r->neg)\n        return 1;\n    return (d->neg ? BN_sub : BN_add) (r, r, d);\n}', 'int BN_div(BIGNUM *dv, BIGNUM *rm, const BIGNUM *num, const BIGNUM *divisor,\n           BN_CTX *ctx)\n{\n    int norm_shift, i, loop;\n    BIGNUM *tmp, wnum, *snum, *sdiv, *res;\n    BN_ULONG *resp, *wnump;\n    BN_ULONG d0, d1;\n    int num_n, div_n;\n    int no_branch = 0;\n    if ((num->top > 0 && num->d[num->top - 1] == 0) ||\n        (divisor->top > 0 && divisor->d[divisor->top - 1] == 0)) {\n        BNerr(BN_F_BN_DIV, BN_R_NOT_INITIALIZED);\n        return 0;\n    }\n    bn_check_top(num);\n    bn_check_top(divisor);\n    if ((BN_get_flags(num, BN_FLG_CONSTTIME) != 0)\n        || (BN_get_flags(divisor, BN_FLG_CONSTTIME) != 0)) {\n        no_branch = 1;\n    }\n    bn_check_top(dv);\n    bn_check_top(rm);\n    if (BN_is_zero(divisor)) {\n        BNerr(BN_F_BN_DIV, BN_R_DIV_BY_ZERO);\n        return (0);\n    }\n    if (!no_branch && BN_ucmp(num, divisor) < 0) {\n        if (rm != NULL) {\n            if (BN_copy(rm, num) == NULL)\n                return (0);\n        }\n        if (dv != NULL)\n            BN_zero(dv);\n        return (1);\n    }\n    BN_CTX_start(ctx);\n    tmp = BN_CTX_get(ctx);\n    snum = BN_CTX_get(ctx);\n    sdiv = BN_CTX_get(ctx);\n    if (dv == NULL)\n        res = BN_CTX_get(ctx);\n    else\n        res = dv;\n    if (sdiv == NULL || res == NULL || tmp == NULL || snum == NULL)\n        goto err;\n    norm_shift = BN_BITS2 - ((BN_num_bits(divisor)) % BN_BITS2);\n    if (!(BN_lshift(sdiv, divisor, norm_shift)))\n        goto err;\n    sdiv->neg = 0;\n    norm_shift += BN_BITS2;\n    if (!(BN_lshift(snum, num, norm_shift)))\n        goto err;\n    snum->neg = 0;\n    if (no_branch) {\n        if (snum->top <= sdiv->top + 1) {\n            if (bn_wexpand(snum, sdiv->top + 2) == NULL)\n                goto err;\n            for (i = snum->top; i < sdiv->top + 2; i++)\n                snum->d[i] = 0;\n            snum->top = sdiv->top + 2;\n        } else {\n            if (bn_wexpand(snum, snum->top + 1) == NULL)\n                goto err;\n            snum->d[snum->top] = 0;\n            snum->top++;\n        }\n    }\n    div_n = sdiv->top;\n    num_n = snum->top;\n    loop = num_n - div_n;\n    wnum.neg = 0;\n    wnum.d = &(snum->d[loop]);\n    wnum.top = div_n;\n    wnum.dmax = snum->dmax - loop;\n    d0 = sdiv->d[div_n - 1];\n    d1 = (div_n == 1) ? 0 : sdiv->d[div_n - 2];\n    wnump = &(snum->d[num_n - 1]);\n    res->neg = (num->neg ^ divisor->neg);\n    if (!bn_wexpand(res, (loop + 1)))\n        goto err;\n    res->top = loop - no_branch;\n    resp = &(res->d[loop - 1]);\n    if (!bn_wexpand(tmp, (div_n + 1)))\n        goto err;\n    if (!no_branch) {\n        if (BN_ucmp(&wnum, sdiv) >= 0) {\n            bn_clear_top2max(&wnum);\n            bn_sub_words(wnum.d, wnum.d, sdiv->d, div_n);\n            *resp = 1;\n        } else\n            res->top--;\n    }\n    if (res->top == 0)\n        res->neg = 0;\n    else\n        resp--;\n    for (i = 0; i < loop - 1; i++, wnump--, resp--) {\n        BN_ULONG q, l0;\n# if defined(BN_DIV3W) && !defined(OPENSSL_NO_ASM)\n        BN_ULONG bn_div_3_words(BN_ULONG *, BN_ULONG, BN_ULONG);\n        q = bn_div_3_words(wnump, d1, d0);\n# else\n        BN_ULONG n0, n1, rem = 0;\n        n0 = wnump[0];\n        n1 = wnump[-1];\n        if (n0 == d0)\n            q = BN_MASK2;\n        else {\n#  ifdef BN_LLONG\n            BN_ULLONG t2;\n#   if defined(BN_LLONG) && defined(BN_DIV2W) && !defined(bn_div_words)\n            q = (BN_ULONG)(((((BN_ULLONG) n0) << BN_BITS2) | n1) / d0);\n#   else\n            q = bn_div_words(n0, n1, d0);\n#    ifdef BN_DEBUG_LEVITTE\n            fprintf(stderr, "DEBUG: bn_div_words(0x%08X,0x%08X,0x%08\\\nX) -> 0x%08X\\n", n0, n1, d0, q);\n#    endif\n#   endif\n#   ifndef REMAINDER_IS_ALREADY_CALCULATED\n            rem = (n1 - q * d0) & BN_MASK2;\n#   endif\n            t2 = (BN_ULLONG) d1 *q;\n            for (;;) {\n                if (t2 <= ((((BN_ULLONG) rem) << BN_BITS2) | wnump[-2]))\n                    break;\n                q--;\n                rem += d0;\n                if (rem < d0)\n                    break;\n                t2 -= d1;\n            }\n#  else\n            BN_ULONG t2l, t2h;\n            q = bn_div_words(n0, n1, d0);\n#   ifdef BN_DEBUG_LEVITTE\n            fprintf(stderr, "DEBUG: bn_div_words(0x%08X,0x%08X,0x%08\\\nX) -> 0x%08X\\n", n0, n1, d0, q);\n#   endif\n#   ifndef REMAINDER_IS_ALREADY_CALCULATED\n            rem = (n1 - q * d0) & BN_MASK2;\n#   endif\n#   if defined(BN_UMULT_LOHI)\n            BN_UMULT_LOHI(t2l, t2h, d1, q);\n#   elif defined(BN_UMULT_HIGH)\n            t2l = d1 * q;\n            t2h = BN_UMULT_HIGH(d1, q);\n#   else\n            {\n                BN_ULONG ql, qh;\n                t2l = LBITS(d1);\n                t2h = HBITS(d1);\n                ql = LBITS(q);\n                qh = HBITS(q);\n                mul64(t2l, t2h, ql, qh);\n            }\n#   endif\n            for (;;) {\n                if ((t2h < rem) || ((t2h == rem) && (t2l <= wnump[-2])))\n                    break;\n                q--;\n                rem += d0;\n                if (rem < d0)\n                    break;\n                if (t2l < d1)\n                    t2h--;\n                t2l -= d1;\n            }\n#  endif\n        }\n# endif\n        l0 = bn_mul_words(tmp->d, sdiv->d, div_n, q);\n        tmp->d[div_n] = l0;\n        wnum.d--;\n        if (bn_sub_words(wnum.d, wnum.d, tmp->d, div_n + 1)) {\n            q--;\n            if (bn_add_words(wnum.d, wnum.d, sdiv->d, div_n))\n                (*wnump)++;\n        }\n        *resp = q;\n    }\n    bn_correct_top(snum);\n    if (rm != NULL) {\n        int neg = num->neg;\n        BN_rshift(rm, snum, norm_shift);\n        if (!BN_is_zero(rm))\n            rm->neg = neg;\n        bn_check_top(rm);\n    }\n    if (no_branch)\n        bn_correct_top(res);\n    BN_CTX_end(ctx);\n    return (1);\n err:\n    bn_check_top(rm);\n    BN_CTX_end(ctx);\n    return (0);\n}', 'void BN_CTX_end(BN_CTX *ctx)\n{\n    CTXDBG_ENTRY("BN_CTX_end", ctx);\n    if (ctx->err_stack)\n        ctx->err_stack--;\n    else {\n        unsigned int fp = BN_STACK_pop(&ctx->stack);\n        if (fp < ctx->used)\n            BN_POOL_release(&ctx->pool, ctx->used - fp);\n        ctx->used = fp;\n        ctx->too_many = 0;\n    }\n    CTXDBG_EXIT(ctx);\n}', 'static unsigned int BN_STACK_pop(BN_STACK *st)\n{\n    return st->indexes[--(st->depth)];\n}']