/*

 * Copyright 2019-2020 The OpenSSL Project Authors. All Rights Reserved.

 *

 * Licensed under the Apache License 2.0 (the "License").  You may not use

 * this file except in compliance with the License.  You can obtain a copy

 * in the file LICENSE in the source distribution or at

 * https://www.openssl.org/source/license.html

 */

#include <string.h>

#include <openssl/trace.h>

#include <openssl/err.h>

#include <openssl/conf.h>

#include <openssl/safestack.h>

#include "internal/provider.h"

DEFINE_STACK_OF(OSSL_PROVIDER)

DEFINE_STACK_OF(CONF_VALUE)

/* PROVIDER config module */

static STACK_OF(OSSL_PROVIDER) *activated_providers = NULL;

static const char *skip_dot(const char *name)

{

    const char *p = strchr(name, '.');

    if (p != NULL)

        return p + 1;

    return name;

}

static int provider_conf_params(OSSL_PROVIDER *prov,

                                const char *name, const char *value,

                                const CONF *cnf)

{

    STACK_OF(CONF_VALUE) *sect;

    int ok = 1;

    sect = NCONF_get_section(cnf, value);

    if (sect != NULL) {

        int i;

        char buffer[512];

        size_t buffer_len = 0;

        OSSL_TRACE1(CONF, "Provider params: start section %s\n", value);

        if (name != NULL) {

            OPENSSL_strlcpy(buffer, name, sizeof(buffer));

            OPENSSL_strlcat(buffer, ".", sizeof(buffer));

            buffer_len = strlen(buffer);

        }

        for (i = 0; i < sk_CONF_VALUE_num(sect); i++) {

            CONF_VALUE *sectconf = sk_CONF_VALUE_value(sect, i);

            if (buffer_len + strlen(sectconf->name) >= sizeof(buffer))

                return 0;

            buffer[buffer_len] = '\0';

            OPENSSL_strlcat(buffer, sectconf->name, sizeof(buffer));

            if (!provider_conf_params(prov, buffer, sectconf->value, cnf))

                return 0;

        }

        OSSL_TRACE1(CONF, "Provider params: finish section %s\n", value);

    } else {

        OSSL_TRACE2(CONF, "Provider params: %s = %s\n", name, value);

        ok = ossl_provider_add_parameter(prov, name, value);

    }

    return ok;

}

static int provider_conf_load(OPENSSL_CTX *libctx, const char *name,

                              const char *value, const CONF *cnf)

{

    int i;

    STACK_OF(CONF_VALUE) *ecmds;

    int soft = 0;

    OSSL_PROVIDER *prov = NULL;

    const char *path = NULL;

    long activate = 0;

    int ok = 0;

    name = skip_dot(name);

    OSSL_TRACE1(CONF, "Configuring provider %s\n", name);

    /* Value is a section containing PROVIDER commands */

    ecmds = NCONF_get_section(cnf, value);

    if (!ecmds) {

        CRYPTOerr(CRYPTO_F_PROVIDER_CONF_LOAD, CRYPTO_R_PROVIDER_SECTION_ERROR);

        return 0;

    }

    /* Find the needed data first */

    for (i = 0; i < sk_CONF_VALUE_num(ecmds); i++) {

        CONF_VALUE *ecmd = sk_CONF_VALUE_value(ecmds, i);

        const char *confname = skip_dot(ecmd->name);

        const char *confvalue = ecmd->value;

        OSSL_TRACE2(CONF, "Provider command: %s = %s\n",

                    confname, confvalue);

        /* First handle some special pseudo confs */

        /* Override provider name to use */

        if (strcmp(confname, "identity") == 0)

            name = confvalue;

        else if (strcmp(confname, "soft_load") == 0)

            soft = 1;

        /* Load a dynamic PROVIDER */

        else if (strcmp(confname, "module") == 0)

            path = confvalue;

        else if (strcmp(confname, "activate") == 0)

            activate = 1;

    }

    prov = ossl_provider_find(libctx, name, 1);

    if (prov == NULL)

        prov = ossl_provider_new(libctx, name, NULL, 1);

    if (prov == NULL) {

        if (soft)

            ERR_clear_error();

        return 0;

    }

    if (path != NULL)

        ossl_provider_set_module_path(prov, path);

    ok = provider_conf_params(prov, NULL, value, cnf);

    if (ok && activate) {

        if (!ossl_provider_activate(prov)) {

            ok = 0;

        } else {

            if (activated_providers == NULL)

                activated_providers = sk_OSSL_PROVIDER_new_null();

            sk_OSSL_PROVIDER_push(activated_providers, prov);

            ok = 1;

        }

    }

    if (!(activate && ok))

        ossl_provider_free(prov);

    return ok;

}

static int provider_conf_init(CONF_IMODULE *md, const CONF *cnf)

{

    STACK_OF(CONF_VALUE) *elist;

    CONF_VALUE *cval;

    int i;

    OSSL_TRACE1(CONF, "Loading providers module: section %s\n",

                CONF_imodule_get_value(md));

    /* Value is a section containing PROVIDERs to configure */

    elist = NCONF_get_section(cnf, CONF_imodule_get_value(md));

    if (!elist) {

        CRYPTOerr(CRYPTO_F_PROVIDER_CONF_INIT,

                  CRYPTO_R_PROVIDER_SECTION_ERROR);

        return 0;

    }

    for (i = 0; i < sk_CONF_VALUE_num(elist); i++) {

        cval = sk_CONF_VALUE_value(elist, i);

        if (!provider_conf_load(cnf->libctx, cval->name, cval->value, cnf))

            return 0;

    }

    return 1;

}

static void provider_conf_deinit(CONF_IMODULE *md)

{

    sk_OSSL_PROVIDER_pop_free(activated_providers, ossl_provider_free);

    activated_providers = NULL;

    OSSL_TRACE(CONF, "Cleaned up providers\n");

}

void ossl_provider_add_conf_module(void)

{

    OSSL_TRACE(CONF, "Adding config module 'providers'\n");

    CONF_module_add("providers", provider_conf_init, provider_conf_deinit);

}