static unsigned int BN_STACK_pop(BN_STACK *st)
{
    return st->indexes[--(st->depth)];
}
['int dsa_builtin_paramgen2(DSA *ret, size_t L, size_t N,\n                          const EVP_MD *evpmd, const unsigned char *seed_in,\n                          size_t seed_len, int idx, unsigned char *seed_out,\n                          int *counter_ret, unsigned long *h_ret,\n                          BN_GENCB *cb)\n{\n    int ok = -1;\n    unsigned char *seed = NULL, *seed_tmp = NULL;\n    unsigned char md[EVP_MAX_MD_SIZE];\n    int mdsize;\n    BIGNUM *r0, *W, *X, *c, *test;\n    BIGNUM *g = NULL, *q = NULL, *p = NULL;\n    BN_MONT_CTX *mont = NULL;\n    int i, k, n = 0, m = 0, qsize = N >> 3;\n    int counter = 0;\n    int r = 0;\n    BN_CTX *ctx = NULL;\n    EVP_MD_CTX *mctx = EVP_MD_CTX_new();\n    unsigned int h = 2;\n    if (mctx == NULL)\n        goto err;\n    if (L <= N) {\n        DSAerr(DSA_F_DSA_BUILTIN_PARAMGEN2, DSA_R_INVALID_PARAMETERS);\n        goto err;\n    }\n    if (evpmd == NULL) {\n        if (N == 160)\n            evpmd = EVP_sha1();\n        else if (N == 224)\n            evpmd = EVP_sha224();\n        else\n            evpmd = EVP_sha256();\n    }\n    mdsize = EVP_MD_size(evpmd);\n    if (!ret->p || !ret->q || idx >= 0) {\n        if (seed_len == 0)\n            seed_len = mdsize;\n        seed = OPENSSL_malloc(seed_len);\n        if (seed_out)\n            seed_tmp = seed_out;\n        else\n            seed_tmp = OPENSSL_malloc(seed_len);\n        if (seed == NULL || seed_tmp == NULL)\n            goto err;\n        if (seed_in)\n            memcpy(seed, seed_in, seed_len);\n    }\n    if ((ctx = BN_CTX_new()) == NULL)\n        goto err;\n    if ((mont = BN_MONT_CTX_new()) == NULL)\n        goto err;\n    BN_CTX_start(ctx);\n    r0 = BN_CTX_get(ctx);\n    g = BN_CTX_get(ctx);\n    W = BN_CTX_get(ctx);\n    X = BN_CTX_get(ctx);\n    c = BN_CTX_get(ctx);\n    test = BN_CTX_get(ctx);\n    if (test == NULL)\n        goto err;\n    if (ret->p && ret->q) {\n        p = ret->p;\n        q = ret->q;\n        if (idx >= 0)\n            memcpy(seed_tmp, seed, seed_len);\n        goto g_only;\n    } else {\n        p = BN_CTX_get(ctx);\n        q = BN_CTX_get(ctx);\n        if (q == NULL)\n            goto err;\n    }\n    if (!BN_lshift(test, BN_value_one(), L - 1))\n        goto err;\n    for (;;) {\n        for (;;) {\n            unsigned char *pmd;\n            if (!BN_GENCB_call(cb, 0, m++))\n                goto err;\n            if (!seed_in) {\n                if (RAND_bytes(seed, seed_len) <= 0)\n                    goto err;\n            }\n            if (!EVP_Digest(seed, seed_len, md, NULL, evpmd, NULL))\n                goto err;\n            if (mdsize > qsize)\n                pmd = md + mdsize - qsize;\n            else\n                pmd = md;\n            if (mdsize < qsize)\n                memset(md + mdsize, 0, qsize - mdsize);\n            pmd[0] |= 0x80;\n            pmd[qsize - 1] |= 0x01;\n            if (!BN_bin2bn(pmd, qsize, q))\n                goto err;\n            r = BN_is_prime_fasttest_ex(q, DSS_prime_checks, ctx,\n                                        seed_in ? 1 : 0, cb);\n            if (r > 0)\n                break;\n            if (r != 0)\n                goto err;\n            if (seed_in) {\n                ok = 0;\n                DSAerr(DSA_F_DSA_BUILTIN_PARAMGEN2, DSA_R_Q_NOT_PRIME);\n                goto err;\n            }\n        }\n        if (seed_out)\n            memcpy(seed_out, seed, seed_len);\n        if (!BN_GENCB_call(cb, 2, 0))\n            goto err;\n        if (!BN_GENCB_call(cb, 3, 0))\n            goto err;\n        counter = 0;\n        n = (L - 1) / (mdsize << 3);\n        for (;;) {\n            if ((counter != 0) && !BN_GENCB_call(cb, 0, counter))\n                goto err;\n            BN_zero(W);\n            for (k = 0; k <= n; k++) {\n                for (i = seed_len - 1; i >= 0; i--) {\n                    seed[i]++;\n                    if (seed[i] != 0)\n                        break;\n                }\n                if (!EVP_Digest(seed, seed_len, md, NULL, evpmd, NULL))\n                    goto err;\n                if (!BN_bin2bn(md, mdsize, r0))\n                    goto err;\n                if (!BN_lshift(r0, r0, (mdsize << 3) * k))\n                    goto err;\n                if (!BN_add(W, W, r0))\n                    goto err;\n            }\n            if (!BN_mask_bits(W, L - 1))\n                goto err;\n            if (!BN_copy(X, W))\n                goto err;\n            if (!BN_add(X, X, test))\n                goto err;\n            if (!BN_lshift1(r0, q))\n                goto err;\n            if (!BN_mod(c, X, r0, ctx))\n                goto err;\n            if (!BN_sub(r0, c, BN_value_one()))\n                goto err;\n            if (!BN_sub(p, X, r0))\n                goto err;\n            if (BN_cmp(p, test) >= 0) {\n                r = BN_is_prime_fasttest_ex(p, DSS_prime_checks, ctx, 1, cb);\n                if (r > 0)\n                    goto end;\n                if (r != 0)\n                    goto err;\n            }\n            counter++;\n            if (counter >= (int)(4 * L))\n                break;\n        }\n        if (seed_in) {\n            ok = 0;\n            DSAerr(DSA_F_DSA_BUILTIN_PARAMGEN2, DSA_R_INVALID_PARAMETERS);\n            goto err;\n        }\n    }\n end:\n    if (!BN_GENCB_call(cb, 2, 1))\n        goto err;\n g_only:\n    if (!BN_sub(test, p, BN_value_one()))\n        goto err;\n    if (!BN_div(r0, NULL, test, q, ctx))\n        goto err;\n    if (idx < 0) {\n        if (!BN_set_word(test, h))\n            goto err;\n    } else\n        h = 1;\n    if (!BN_MONT_CTX_set(mont, p, ctx))\n        goto err;\n    for (;;) {\n        static const unsigned char ggen[4] = { 0x67, 0x67, 0x65, 0x6e };\n        if (idx >= 0) {\n            md[0] = idx & 0xff;\n            md[1] = (h >> 8) & 0xff;\n            md[2] = h & 0xff;\n            if (!EVP_DigestInit_ex(mctx, evpmd, NULL))\n                goto err;\n            if (!EVP_DigestUpdate(mctx, seed_tmp, seed_len))\n                goto err;\n            if (!EVP_DigestUpdate(mctx, ggen, sizeof(ggen)))\n                goto err;\n            if (!EVP_DigestUpdate(mctx, md, 3))\n                goto err;\n            if (!EVP_DigestFinal_ex(mctx, md, NULL))\n                goto err;\n            if (!BN_bin2bn(md, mdsize, test))\n                goto err;\n        }\n        if (!BN_mod_exp_mont(g, test, r0, p, ctx, mont))\n            goto err;\n        if (!BN_is_one(g))\n            break;\n        if (idx < 0 && !BN_add(test, test, BN_value_one()))\n            goto err;\n        h++;\n        if (idx >= 0 && h > 0xffff)\n            goto err;\n    }\n    if (!BN_GENCB_call(cb, 3, 1))\n        goto err;\n    ok = 1;\n err:\n    if (ok == 1) {\n        if (p != ret->p) {\n            BN_free(ret->p);\n            ret->p = BN_dup(p);\n        }\n        if (q != ret->q) {\n            BN_free(ret->q);\n            ret->q = BN_dup(q);\n        }\n        BN_free(ret->g);\n        ret->g = BN_dup(g);\n        if (ret->p == NULL || ret->q == NULL || ret->g == NULL) {\n            ok = -1;\n            goto err;\n        }\n        if (counter_ret != NULL)\n            *counter_ret = counter;\n        if (h_ret != NULL)\n            *h_ret = h;\n    }\n    OPENSSL_free(seed);\n    if (seed_out != seed_tmp)\n        OPENSSL_free(seed_tmp);\n    if (ctx)\n        BN_CTX_end(ctx);\n    BN_CTX_free(ctx);\n    BN_MONT_CTX_free(mont);\n    EVP_MD_CTX_free(mctx);\n    return ok;\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_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}']