crypto/ec/ecp_smpl.c:1401: error: INTEGER_OVERFLOW_L2
  ([0, +oo] - 1):unsigned32 by call to `BN_mod_inverse`.
Showing all 45 steps of the trace


crypto/ec/ecp_smpl.c:1378:1: Parameter `ctx->stack.depth`
1376.    * Since we don't have a Mont structure here, SCA hardening is with blinding.
1377.    */
1378. > int ec_GFp_simple_field_inv(const EC_GROUP *group, BIGNUM *r, const BIGNUM *a,
1379.                               BN_CTX *ctx)
1380.   {

crypto/ec/ecp_smpl.c:1388:5: Call
1386.           return 0;
1387.   
1388.       BN_CTX_start(ctx);
            ^
1389.       if ((e = BN_CTX_get(ctx)) == NULL)
1390.           goto err;

crypto/bn/bn_ctx.c:171:1: Parameter `ctx->stack.depth`
  169.   }
  170.   
  171. > void BN_CTX_start(BN_CTX *ctx)
  172.   {
  173.       CTXDBG("ENTER BN_CTX_start()", ctx);

crypto/ec/ecp_smpl.c:1401:10: Call
1399.           goto err;
1400.       /* r := 1/(a * e) */
1401.       if (!BN_mod_inverse(r, r, group->field, ctx)) {
                 ^
1402.           ECerr(EC_F_EC_GFP_SIMPLE_FIELD_INV, EC_R_CANNOT_INVERT);
1403.           goto err;

crypto/bn/bn_gcd.c:124:1: Parameter `ctx->stack.depth`
  122.                                           BN_CTX *ctx);
  123.   
  124. > BIGNUM *BN_mod_inverse(BIGNUM *in,
  125.                          const BIGNUM *a, const BIGNUM *n, BN_CTX *ctx)
  126.   {

crypto/bn/bn_gcd.c:129:10: Call
  127.       BIGNUM *rv;
  128.       int noinv;
  129.       rv = int_bn_mod_inverse(in, a, n, ctx, &noinv);
                  ^
  130.       if (noinv)
  131.           BNerr(BN_F_BN_MOD_INVERSE, BN_R_NO_INVERSE);

crypto/bn/bn_gcd.c:135:1: Parameter `ctx->stack.depth`
    133.   }
    134.   
    135. > BIGNUM *int_bn_mod_inverse(BIGNUM *in,
    136.                              const BIGNUM *a, const BIGNUM *n, BN_CTX *ctx,
    137.                              int *pnoinv)

crypto/bn/bn_gcd.c:155:16: Call
    153.       if ((BN_get_flags(a, BN_FLG_CONSTTIME) != 0)
    154.           || (BN_get_flags(n, BN_FLG_CONSTTIME) != 0)) {
    155.           return BN_mod_inverse_no_branch(in, a, n, ctx);
                          ^
    156.       }
    157.   

crypto/bn/bn_gcd.c:458:1: Parameter `ctx->stack.depth`
      456.    * not contain branches that may leak sensitive information.
      457.    */
      458. > static BIGNUM *BN_mod_inverse_no_branch(BIGNUM *in,
      459.                                           const BIGNUM *a, const BIGNUM *n,
      460.                                           BN_CTX *ctx)

crypto/bn/bn_gcd.c:469:5: Call
      467.       bn_check_top(n);
      468.   
      469.       BN_CTX_start(ctx);
                 ^
      470.       A = BN_CTX_get(ctx);
      471.       B = BN_CTX_get(ctx);

crypto/bn/bn_ctx.c:171:1: Parameter `ctx->stack.depth`
        169.   }
        170.   
        171. > void BN_CTX_start(BN_CTX *ctx)
        172.   {
        173.       CTXDBG("ENTER BN_CTX_start()", ctx);

crypto/bn/bn_gcd.c:470:9: Call
      468.   
      469.       BN_CTX_start(ctx);
      470.       A = BN_CTX_get(ctx);
                     ^
      471.       B = BN_CTX_get(ctx);
      472.       X = BN_CTX_get(ctx);

crypto/bn/bn_ctx.c:202:1: Parameter `ctx->stack.depth`
        200.   }
        201.   
        202. > BIGNUM *BN_CTX_get(BN_CTX *ctx)
        203.   {
        204.       BIGNUM *ret;

crypto/bn/bn_gcd.c:471:9: Call
      469.       BN_CTX_start(ctx);
      470.       A = BN_CTX_get(ctx);
      471.       B = BN_CTX_get(ctx);
                     ^
      472.       X = BN_CTX_get(ctx);
      473.       D = BN_CTX_get(ctx);

crypto/bn/bn_ctx.c:202:1: Parameter `ctx->stack.depth`
        200.   }
        201.   
        202. > BIGNUM *BN_CTX_get(BN_CTX *ctx)
        203.   {
        204.       BIGNUM *ret;

crypto/bn/bn_gcd.c:472:9: Call
      470.       A = BN_CTX_get(ctx);
      471.       B = BN_CTX_get(ctx);
      472.       X = BN_CTX_get(ctx);
                     ^
      473.       D = BN_CTX_get(ctx);
      474.       M = BN_CTX_get(ctx);

crypto/bn/bn_ctx.c:202:1: Parameter `ctx->stack.depth`
        200.   }
        201.   
        202. > BIGNUM *BN_CTX_get(BN_CTX *ctx)
        203.   {
        204.       BIGNUM *ret;

crypto/bn/bn_gcd.c:473:9: Call
      471.       B = BN_CTX_get(ctx);
      472.       X = BN_CTX_get(ctx);
      473.       D = BN_CTX_get(ctx);
                     ^
      474.       M = BN_CTX_get(ctx);
      475.       Y = BN_CTX_get(ctx);

crypto/bn/bn_ctx.c:202:1: Parameter `ctx->stack.depth`
        200.   }
        201.   
        202. > BIGNUM *BN_CTX_get(BN_CTX *ctx)
        203.   {
        204.       BIGNUM *ret;

crypto/bn/bn_gcd.c:474:9: Call
      472.       X = BN_CTX_get(ctx);
      473.       D = BN_CTX_get(ctx);
      474.       M = BN_CTX_get(ctx);
                     ^
      475.       Y = BN_CTX_get(ctx);
      476.       T = BN_CTX_get(ctx);

crypto/bn/bn_ctx.c:202:1: Parameter `ctx->stack.depth`
        200.   }
        201.   
        202. > BIGNUM *BN_CTX_get(BN_CTX *ctx)
        203.   {
        204.       BIGNUM *ret;

crypto/bn/bn_gcd.c:475:9: Call
      473.       D = BN_CTX_get(ctx);
      474.       M = BN_CTX_get(ctx);
      475.       Y = BN_CTX_get(ctx);
                     ^
      476.       T = BN_CTX_get(ctx);
      477.       if (T == NULL)

crypto/bn/bn_ctx.c:202:1: Parameter `ctx->stack.depth`
        200.   }
        201.   
        202. > BIGNUM *BN_CTX_get(BN_CTX *ctx)
        203.   {
        204.       BIGNUM *ret;

crypto/bn/bn_gcd.c:476:9: Call
      474.       M = BN_CTX_get(ctx);
      475.       Y = BN_CTX_get(ctx);
      476.       T = BN_CTX_get(ctx);
                     ^
      477.       if (T == NULL)
      478.           goto err;

crypto/bn/bn_ctx.c:202:1: Parameter `ctx->stack.depth`
        200.   }
        201.   
        202. > BIGNUM *BN_CTX_get(BN_CTX *ctx)
        203.   {
        204.       BIGNUM *ret;

crypto/bn/bn_gcd.c:504:18: Call
      502.               bn_init(&local_B);
      503.               BN_with_flags(&local_B, B, BN_FLG_CONSTTIME);
      504.               if (!BN_nnmod(B, &local_B, A, ctx))
                              ^
      505.                   goto err;
      506.               /* Ensure local_B goes out of scope before any further use of B */

crypto/bn/bn_mod.c:13:1: Parameter `ctx->stack.depth`
        11.   #include "bn_lcl.h"
        12.   
        13. > int BN_nnmod(BIGNUM *r, const BIGNUM *m, const BIGNUM *d, BN_CTX *ctx)
        14.   {
        15.       /*

crypto/bn/bn_mod.c:20:11: Call
        18.        */
        19.   
        20.       if (!(BN_mod(r, m, d, ctx)))
                        ^
        21.           return 0;
        22.       if (!r->neg)

crypto/bn/bn_div.c:209:1: Parameter `ctx->stack.depth`
          207.    * If 'dv' or 'rm' is NULL, the respective value is not returned.
          208.    */
          209. > int BN_div(BIGNUM *dv, BIGNUM *rm, const BIGNUM *num, const BIGNUM *divisor,
          210.              BN_CTX *ctx)
          211.   {

crypto/bn/bn_div.c:229:11: Call
          227.       }
          228.   
          229.       ret = bn_div_fixed_top(dv, rm, num, divisor, ctx);
                           ^
          230.   
          231.       if (ret) {

crypto/bn/bn_div.c:264:1: Parameter `ctx->stack.depth`
            262.    *       divisor's length is considered public;
            263.    */
            264. > int bn_div_fixed_top(BIGNUM *dv, BIGNUM *rm, const BIGNUM *num,
            265.                        const BIGNUM *divisor, BN_CTX *ctx)
            266.   {

crypto/bn/bn_div.c:280:5: Call
            278.       bn_check_top(rm);
            279.   
            280.       BN_CTX_start(ctx);
                       ^
            281.       res = (dv == NULL) ? BN_CTX_get(ctx) : dv;
            282.       tmp = BN_CTX_get(ctx);

crypto/bn/bn_ctx.c:171:1: Parameter `ctx->stack.depth`
              169.   }
              170.   
              171. > void BN_CTX_start(BN_CTX *ctx)
              172.   {
              173.       CTXDBG("ENTER BN_CTX_start()", ctx);

crypto/bn/bn_div.c:282:11: Call
            280.       BN_CTX_start(ctx);
            281.       res = (dv == NULL) ? BN_CTX_get(ctx) : dv;
            282.       tmp = BN_CTX_get(ctx);
                             ^
            283.       snum = BN_CTX_get(ctx);
            284.       sdiv = BN_CTX_get(ctx);

crypto/bn/bn_ctx.c:202:1: Parameter `ctx->stack.depth`
              200.   }
              201.   
              202. > BIGNUM *BN_CTX_get(BN_CTX *ctx)
              203.   {
              204.       BIGNUM *ret;

crypto/bn/bn_div.c:283:12: Call
            281.       res = (dv == NULL) ? BN_CTX_get(ctx) : dv;
            282.       tmp = BN_CTX_get(ctx);
            283.       snum = BN_CTX_get(ctx);
                              ^
            284.       sdiv = BN_CTX_get(ctx);
            285.       if (sdiv == NULL)

crypto/bn/bn_ctx.c:202:1: Parameter `ctx->stack.depth`
              200.   }
              201.   
              202. > BIGNUM *BN_CTX_get(BN_CTX *ctx)
              203.   {
              204.       BIGNUM *ret;

crypto/bn/bn_div.c:284:12: Call
            282.       tmp = BN_CTX_get(ctx);
            283.       snum = BN_CTX_get(ctx);
            284.       sdiv = BN_CTX_get(ctx);
                              ^
            285.       if (sdiv == NULL)
            286.           goto err;

crypto/bn/bn_ctx.c:202:1: Parameter `ctx->stack.depth`
              200.   }
              201.   
              202. > BIGNUM *BN_CTX_get(BN_CTX *ctx)
              203.   {
              204.       BIGNUM *ret;

crypto/bn/bn_div.c:450:5: Call
            448.       if (rm != NULL)
            449.           bn_rshift_fixed_top(rm, snum, norm_shift);
            450.       BN_CTX_end(ctx);
                       ^
            451.       return 1;
            452.    err:

crypto/bn/bn_ctx.c:185:1: Parameter `ctx->stack.depth`
              183.   }
              184.   
              185. > void BN_CTX_end(BN_CTX *ctx)
              186.   {
              187.       CTXDBG("ENTER BN_CTX_end()", ctx);

crypto/bn/bn_ctx.c:191:27: Call
              189.           ctx->err_stack--;
              190.       else {
              191.           unsigned int fp = BN_STACK_pop(&ctx->stack);
                                               ^
              192.           /* Does this stack frame have anything to release? */
              193.           if (fp < ctx->used)

crypto/bn/bn_ctx.c:266:1: <LHS trace>
264.   }
265.   
266. > static unsigned int BN_STACK_pop(BN_STACK *st)
267.   {
268.       return st->indexes[--(st->depth)];

crypto/bn/bn_ctx.c:266:1: Parameter `st->depth`
                264.   }
                265.   
                266. > static unsigned int BN_STACK_pop(BN_STACK *st)
                267.   {
                268.       return st->indexes[--(st->depth)];

crypto/bn/bn_ctx.c:268:12: Binary operation: ([0, +oo] - 1):unsigned32 by call to `BN_mod_inverse` 
                266.   static unsigned int BN_STACK_pop(BN_STACK *st)
                267.   {
                268.       return st->indexes[--(st->depth)];
                                  ^
                269.   }
                270.   

static unsigned int BN_STACK_pop(BN_STACK *st)
{
    return st->indexes[--(st->depth)];
}
['int ec_GFp_simple_field_inv(const EC_GROUP *group, BIGNUM *r, const BIGNUM *a,\n                            BN_CTX *ctx)\n{\n    BIGNUM *e = NULL;\n    BN_CTX *new_ctx = NULL;\n    int ret = 0;\n    if (ctx == NULL && (ctx = new_ctx = BN_CTX_secure_new()) == NULL)\n        return 0;\n    BN_CTX_start(ctx);\n    if ((e = BN_CTX_get(ctx)) == NULL)\n        goto err;\n    do {\n        if (!BN_priv_rand_range(e, group->field))\n        goto err;\n    } while (BN_is_zero(e));\n    if (!group->meth->field_mul(group, r, a, e, ctx))\n        goto err;\n    if (!BN_mod_inverse(r, r, group->field, ctx)) {\n        ECerr(EC_F_EC_GFP_SIMPLE_FIELD_INV, EC_R_CANNOT_INVERT);\n        goto err;\n    }\n    if (!group->meth->field_mul(group, r, r, e, ctx))\n        goto err;\n    ret = 1;\n err:\n    BN_CTX_end(ctx);\n    BN_CTX_free(new_ctx);\n    return ret;\n}', 'void BN_CTX_start(BN_CTX *ctx)\n{\n    CTXDBG("ENTER 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("LEAVE BN_CTX_start()", ctx);\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 (BN_abs_is_word(n, 1) || BN_is_zero(n)) {\n        if (pnoinv != NULL)\n            *pnoinv = 1;\n        return NULL;\n    }\n    if (pnoinv != NULL)\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) <= 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 *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         {\n            BIGNUM local_B;\n            bn_init(&local_B);\n            BN_with_flags(&local_B, B, BN_FLG_CONSTTIME);\n            if (!BN_nnmod(B, &local_B, A, ctx))\n                goto err;\n        }\n    }\n    sign = -1;\n    while (!BN_is_zero(B)) {\n        BIGNUM *tmp;\n        {\n            BIGNUM local_A;\n            bn_init(&local_A);\n            BN_with_flags(&local_A, A, BN_FLG_CONSTTIME);\n            if (!BN_div(D, M, &local_A, B, ctx))\n                goto err;\n        }\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}', 'BIGNUM *BN_CTX_get(BN_CTX *ctx)\n{\n    BIGNUM *ret;\n    CTXDBG("ENTER BN_CTX_get()", ctx);\n    if (ctx->err_stack || ctx->too_many)\n        return NULL;\n    if ((ret = BN_POOL_get(&ctx->pool, ctx->flags)) == NULL) {\n        ctx->too_many = 1;\n        BNerr(BN_F_BN_CTX_GET, BN_R_TOO_MANY_TEMPORARY_VARIABLES);\n        return NULL;\n    }\n    BN_zero(ret);\n    ret->flags &= (~BN_FLG_CONSTTIME);\n    ctx->used++;\n    CTXDBG("LEAVE BN_CTX_get()", ctx);\n    return ret;\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 ret;\n    if (BN_is_zero(divisor)) {\n        BNerr(BN_F_BN_DIV, BN_R_DIV_BY_ZERO);\n        return 0;\n    }\n    if (divisor->d[divisor->top - 1] == 0) {\n        BNerr(BN_F_BN_DIV, BN_R_NOT_INITIALIZED);\n        return 0;\n    }\n    ret = bn_div_fixed_top(dv, rm, num, divisor, ctx);\n    if (ret) {\n        if (dv != NULL)\n            bn_correct_top(dv);\n        if (rm != NULL)\n            bn_correct_top(rm);\n    }\n    return ret;\n}', 'int bn_div_fixed_top(BIGNUM *dv, BIGNUM *rm, const BIGNUM *num,\n                     const BIGNUM *divisor, BN_CTX *ctx)\n{\n    int norm_shift, i, j, loop;\n    BIGNUM *tmp, *snum, *sdiv, *res;\n    BN_ULONG *resp, *wnum, *wnumtop;\n    BN_ULONG d0, d1;\n    int num_n, div_n;\n    assert(divisor->top > 0 && divisor->d[divisor->top - 1] != 0);\n    bn_check_top(num);\n    bn_check_top(divisor);\n    bn_check_top(dv);\n    bn_check_top(rm);\n    BN_CTX_start(ctx);\n    res = (dv == NULL) ? BN_CTX_get(ctx) : dv;\n    tmp = BN_CTX_get(ctx);\n    snum = BN_CTX_get(ctx);\n    sdiv = BN_CTX_get(ctx);\n    if (sdiv == NULL)\n        goto err;\n    if (!BN_copy(sdiv, divisor))\n        goto err;\n    norm_shift = bn_left_align(sdiv);\n    sdiv->neg = 0;\n    if (!(bn_lshift_fixed_top(snum, num, norm_shift)))\n        goto err;\n    div_n = sdiv->top;\n    num_n = snum->top;\n    if (num_n <= div_n) {\n        if (bn_wexpand(snum, div_n + 1) == NULL)\n            goto err;\n        memset(&(snum->d[num_n]), 0, (div_n - num_n + 1) * sizeof(BN_ULONG));\n        snum->top = num_n = div_n + 1;\n    }\n    loop = num_n - div_n;\n    wnum = &(snum->d[loop]);\n    wnumtop = &(snum->d[num_n - 1]);\n    d0 = sdiv->d[div_n - 1];\n    d1 = (div_n == 1) ? 0 : sdiv->d[div_n - 2];\n    if (!bn_wexpand(res, loop))\n        goto err;\n    res->neg = (num->neg ^ divisor->neg);\n    res->top = loop;\n    res->flags |= BN_FLG_FIXED_TOP;\n    resp = &(res->d[loop]);\n    if (!bn_wexpand(tmp, (div_n + 1)))\n        goto err;\n    for (i = 0; i < loop; i++, wnumtop--) {\n        BN_ULONG q, l0;\n# if defined(BN_DIV3W)\n        q = bn_div_3_words(wnumtop, d1, d0);\n# else\n        BN_ULONG n0, n1, rem = 0;\n        n0 = wnumtop[0];\n        n1 = wnumtop[-1];\n        if (n0 == d0)\n            q = BN_MASK2;\n        else {\n            BN_ULONG n2 = (wnumtop == wnum) ? 0 : wnumtop[-2];\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#   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) | n2))\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#   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 <= n2)))\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--;\n        l0 = bn_sub_words(wnum, wnum, tmp->d, div_n + 1);\n        q -= l0;\n        for (l0 = 0 - l0, j = 0; j < div_n; j++)\n            tmp->d[j] = sdiv->d[j] & l0;\n        l0 = bn_add_words(wnum, wnum, tmp->d, div_n);\n        (*wnumtop) += l0;\n        assert((*wnumtop) == 0);\n        *--resp = q;\n    }\n    snum->neg = num->neg;\n    snum->top = div_n;\n    snum->flags |= BN_FLG_FIXED_TOP;\n    if (rm != NULL)\n        bn_rshift_fixed_top(rm, snum, norm_shift);\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("ENTER 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("LEAVE BN_CTX_end()", ctx);\n}', 'static unsigned int BN_STACK_pop(BN_STACK *st)\n{\n    return st->indexes[--(st->depth)];\n}']