crypto/dsa/dsa_key.c:58: error: INTEGER_OVERFLOW_L2
  ([0, +oo] - 1):unsigned32 by call to `BN_mod_exp`.
Showing all 32 steps of the trace


crypto/dsa/dsa_key.c:58:14: Call
56.           BN_with_flags(prk, priv_key, BN_FLG_CONSTTIME);
57.   
58.           if (!BN_mod_exp(pub_key, dsa->g, prk, dsa->p, ctx)) {
                   ^
59.               BN_free(prk);
60.               goto err;

crypto/bn/bn_exp.c:89:1: Parameter `ctx->stack.depth`
  87.   }
  88.   
  89. > int BN_mod_exp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p, const BIGNUM *m,
  90.                  BN_CTX *ctx)
  91.   {

crypto/bn/bn_exp.c:141:19: Call
  139.               && (BN_get_flags(m, BN_FLG_CONSTTIME) == 0)) {
  140.               BN_ULONG A = a->d[0];
  141.               ret = BN_mod_exp_mont_word(r, A, p, m, ctx, NULL);
                           ^
  142.           } else
  143.   # endif

crypto/bn/bn_exp.c:1129:1: Parameter `ctx->stack.depth`
    1127.   }
    1128.   
    1129. > int BN_mod_exp_mont_word(BIGNUM *rr, BN_ULONG a, const BIGNUM *p,
    1130.                            const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *in_mont)
    1131.   {

crypto/bn/bn_exp.c:1189:5: Call
    1187.       }
    1188.   
    1189.       BN_CTX_start(ctx);
                ^
    1190.       r = BN_CTX_get(ctx);
    1191.       t = 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_exp.c:1200:14: Call
    1198.           if ((mont = BN_MONT_CTX_new()) == NULL)
    1199.               goto err;
    1200.           if (!BN_MONT_CTX_set(mont, m, ctx))
                         ^
    1201.               goto err;
    1202.       }

crypto/bn/bn_mont.c:263:1: Parameter `ctx->stack.depth`
      261.   }
      262.   
      263. > int BN_MONT_CTX_set(BN_MONT_CTX *mont, const BIGNUM *mod, BN_CTX *ctx)
      264.   {
      265.       int i, ret = 0;

crypto/bn/bn_mont.c:271:5: Call
      269.           return 0;
      270.   
      271.       BN_CTX_start(ctx);
                 ^
      272.       if ((Ri = BN_CTX_get(ctx)) == NULL)
      273.           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/bn/bn_mont.c:351:19: Call
      349.           if (BN_is_one(&tmod))
      350.               BN_zero(Ri);
      351.           else if ((BN_mod_inverse(Ri, R, &tmod, ctx)) == NULL)
                               ^
      352.               goto err;
      353.           if (!BN_lshift(Ri, Ri, BN_BITS2))

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: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: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_exp` 
                      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)];
}
['static int dsa_builtin_keygen(DSA *dsa)\n{\n    int ok = 0;\n    BN_CTX *ctx = NULL;\n    BIGNUM *pub_key = NULL, *priv_key = NULL;\n    if ((ctx = BN_CTX_new()) == NULL)\n        goto err;\n    if (dsa->priv_key == NULL) {\n        if ((priv_key = BN_secure_new()) == NULL)\n            goto err;\n    } else\n        priv_key = dsa->priv_key;\n    do\n        if (!BN_priv_rand_range(priv_key, dsa->q))\n            goto err;\n    while (BN_is_zero(priv_key)) ;\n    if (dsa->pub_key == NULL) {\n        if ((pub_key = BN_new()) == NULL)\n            goto err;\n    } else\n        pub_key = dsa->pub_key;\n    {\n        BIGNUM *prk = BN_new();\n        if (prk == NULL)\n            goto err;\n        BN_with_flags(prk, priv_key, BN_FLG_CONSTTIME);\n        if (!BN_mod_exp(pub_key, dsa->g, prk, dsa->p, ctx)) {\n            BN_free(prk);\n            goto err;\n        }\n        BN_free(prk);\n    }\n    dsa->priv_key = priv_key;\n    dsa->pub_key = pub_key;\n    ok = 1;\n err:\n    if (pub_key != dsa->pub_key)\n        BN_free(pub_key);\n    if (priv_key != dsa->priv_key)\n        BN_free(priv_key);\n    BN_CTX_free(ctx);\n    return ok;\n}', 'int BN_mod_exp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p, const BIGNUM *m,\n               BN_CTX *ctx)\n{\n    int ret;\n    bn_check_top(a);\n    bn_check_top(p);\n    bn_check_top(m);\n#define MONT_MUL_MOD\n#define MONT_EXP_WORD\n#define RECP_MUL_MOD\n#ifdef MONT_MUL_MOD\n    if (BN_is_odd(m)) {\n# ifdef MONT_EXP_WORD\n        if (a->top == 1 && !a->neg\n            && (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            BN_ULONG A = a->d[0];\n            ret = BN_mod_exp_mont_word(r, A, p, m, ctx, NULL);\n        } else\n# endif\n            ret = BN_mod_exp_mont(r, a, p, m, ctx, NULL);\n    } else\n#endif\n#ifdef RECP_MUL_MOD\n    {\n        ret = BN_mod_exp_recp(r, a, p, m, ctx);\n    }\n#else\n    {\n        ret = BN_mod_exp_simple(r, a, p, m, ctx);\n    }\n#endif\n    bn_check_top(r);\n    return ret;\n}', 'int BN_mod_exp_mont_word(BIGNUM *rr, BN_ULONG a, const BIGNUM *p,\n                         const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *in_mont)\n{\n    BN_MONT_CTX *mont = NULL;\n    int b, bits, ret = 0;\n    int r_is_one;\n    BN_ULONG w, next_w;\n    BIGNUM *r, *t;\n    BIGNUM *swap_tmp;\n#define BN_MOD_MUL_WORD(r, w, m) \\\n                (BN_mul_word(r, (w)) && \\\n                (   \\\n                        (BN_mod(t, r, m, ctx) && (swap_tmp = r, r = t, t = swap_tmp, 1))))\n#define BN_TO_MONTGOMERY_WORD(r, w, mont) \\\n                (BN_set_word(r, (w)) && BN_to_montgomery(r, r, (mont), ctx))\n    if (BN_get_flags(p, BN_FLG_CONSTTIME) != 0\n            || BN_get_flags(m, BN_FLG_CONSTTIME) != 0) {\n        BNerr(BN_F_BN_MOD_EXP_MONT_WORD, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);\n        return 0;\n    }\n    bn_check_top(p);\n    bn_check_top(m);\n    if (!BN_is_odd(m)) {\n        BNerr(BN_F_BN_MOD_EXP_MONT_WORD, BN_R_CALLED_WITH_EVEN_MODULUS);\n        return 0;\n    }\n    if (m->top == 1)\n        a %= m->d[0];\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    if (a == 0) {\n        BN_zero(rr);\n        ret = 1;\n        return ret;\n    }\n    BN_CTX_start(ctx);\n    r = BN_CTX_get(ctx);\n    t = BN_CTX_get(ctx);\n    if (t == 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    r_is_one = 1;\n    w = a;\n    for (b = bits - 2; b >= 0; b--) {\n        next_w = w * w;\n        if ((next_w / w) != w) {\n            if (r_is_one) {\n                if (!BN_TO_MONTGOMERY_WORD(r, w, mont))\n                    goto err;\n                r_is_one = 0;\n            } else {\n                if (!BN_MOD_MUL_WORD(r, w, m))\n                    goto err;\n            }\n            next_w = 1;\n        }\n        w = next_w;\n        if (!r_is_one) {\n            if (!BN_mod_mul_montgomery(r, r, r, mont, ctx))\n                goto err;\n        }\n        if (BN_is_bit_set(p, b)) {\n            next_w = w * a;\n            if ((next_w / a) != w) {\n                if (r_is_one) {\n                    if (!BN_TO_MONTGOMERY_WORD(r, w, mont))\n                        goto err;\n                    r_is_one = 0;\n                } else {\n                    if (!BN_MOD_MUL_WORD(r, w, m))\n                        goto err;\n                }\n                next_w = a;\n            }\n            w = next_w;\n        }\n    }\n    if (w != 1) {\n        if (r_is_one) {\n            if (!BN_TO_MONTGOMERY_WORD(r, w, mont))\n                goto err;\n            r_is_one = 0;\n        } else {\n            if (!BN_MOD_MUL_WORD(r, w, m))\n                goto err;\n        }\n    }\n    if (r_is_one) {\n        if (!BN_one(rr))\n            goto err;\n    } else {\n        if (!BN_from_montgomery(rr, r, mont, ctx))\n            goto err;\n    }\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}', '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}', 'int BN_MONT_CTX_set(BN_MONT_CTX *mont, const BIGNUM *mod, BN_CTX *ctx)\n{\n    int i, ret = 0;\n    BIGNUM *Ri, *R;\n    if (BN_is_zero(mod))\n        return 0;\n    BN_CTX_start(ctx);\n    if ((Ri = BN_CTX_get(ctx)) == NULL)\n        goto err;\n    R = &(mont->RR);\n    if (!BN_copy(&(mont->N), mod))\n        goto err;\n    if (BN_get_flags(mod, BN_FLG_CONSTTIME) != 0)\n        BN_set_flags(&(mont->N), BN_FLG_CONSTTIME);\n    mont->N.neg = 0;\n#ifdef MONT_WORD\n    {\n        BIGNUM tmod;\n        BN_ULONG buf[2];\n        bn_init(&tmod);\n        tmod.d = buf;\n        tmod.dmax = 2;\n        tmod.neg = 0;\n        if (BN_get_flags(mod, BN_FLG_CONSTTIME) != 0)\n            BN_set_flags(&tmod, BN_FLG_CONSTTIME);\n        mont->ri = (BN_num_bits(mod) + (BN_BITS2 - 1)) / BN_BITS2 * BN_BITS2;\n# if defined(OPENSSL_BN_ASM_MONT) && (BN_BITS2<=32)\n        BN_zero(R);\n        if (!(BN_set_bit(R, 2 * BN_BITS2)))\n            goto err;\n        tmod.top = 0;\n        if ((buf[0] = mod->d[0]))\n            tmod.top = 1;\n        if ((buf[1] = mod->top > 1 ? mod->d[1] : 0))\n            tmod.top = 2;\n        if (BN_is_one(&tmod))\n            BN_zero(Ri);\n        else if ((BN_mod_inverse(Ri, R, &tmod, ctx)) == NULL)\n            goto err;\n        if (!BN_lshift(Ri, Ri, 2 * BN_BITS2))\n            goto err;\n        if (!BN_is_zero(Ri)) {\n            if (!BN_sub_word(Ri, 1))\n                goto err;\n        } else {\n            if (bn_expand(Ri, (int)sizeof(BN_ULONG) * 2) == NULL)\n                goto err;\n            Ri->neg = 0;\n            Ri->d[0] = BN_MASK2;\n            Ri->d[1] = BN_MASK2;\n            Ri->top = 2;\n        }\n        if (!BN_div(Ri, NULL, Ri, &tmod, ctx))\n            goto err;\n        mont->n0[0] = (Ri->top > 0) ? Ri->d[0] : 0;\n        mont->n0[1] = (Ri->top > 1) ? Ri->d[1] : 0;\n# else\n        BN_zero(R);\n        if (!(BN_set_bit(R, BN_BITS2)))\n            goto err;\n        buf[0] = mod->d[0];\n        buf[1] = 0;\n        tmod.top = buf[0] != 0 ? 1 : 0;\n        if (BN_is_one(&tmod))\n            BN_zero(Ri);\n        else if ((BN_mod_inverse(Ri, R, &tmod, ctx)) == NULL)\n            goto err;\n        if (!BN_lshift(Ri, Ri, BN_BITS2))\n            goto err;\n        if (!BN_is_zero(Ri)) {\n            if (!BN_sub_word(Ri, 1))\n                goto err;\n        } else {\n            if (!BN_set_word(Ri, BN_MASK2))\n                goto err;\n        }\n        if (!BN_div(Ri, NULL, Ri, &tmod, ctx))\n            goto err;\n        mont->n0[0] = (Ri->top > 0) ? Ri->d[0] : 0;\n        mont->n0[1] = 0;\n# endif\n    }\n#else\n    {\n        mont->ri = BN_num_bits(&mont->N);\n        BN_zero(R);\n        if (!BN_set_bit(R, mont->ri))\n            goto err;\n        if ((BN_mod_inverse(Ri, R, &mont->N, ctx)) == NULL)\n            goto err;\n        if (!BN_lshift(Ri, Ri, mont->ri))\n            goto err;\n        if (!BN_sub_word(Ri, 1))\n            goto err;\n        if (!BN_div(&(mont->Ni), NULL, Ri, &mont->N, ctx))\n            goto err;\n    }\n#endif\n    BN_zero(&(mont->RR));\n    if (!BN_set_bit(&(mont->RR), mont->ri * 2))\n        goto err;\n    if (!BN_mod(&(mont->RR), &(mont->RR), &(mont->N), ctx))\n        goto err;\n    for (i = mont->RR.top, ret = mont->N.top; i < ret; i++)\n        mont->RR.d[i] = 0;\n    mont->RR.top = ret;\n    mont->RR.flags |= BN_FLG_FIXED_TOP;\n    ret = 1;\n err:\n    BN_CTX_end(ctx);\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 (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}', '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}']