/*

 * Copyright 2006-2016 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 <stdio.h>

#include <stdlib.h>

#include <openssl/objects.h>

#include <openssl/evp.h>

#include "internal/cryptlib.h"

#include "crypto/evp.h"

#include "internal/provider.h"

#include "evp_local.h"

static EVP_SIGNATURE *evp_signature_new(OSSL_PROVIDER *prov)

{

    EVP_SIGNATURE *signature = OPENSSL_zalloc(sizeof(EVP_SIGNATURE));

    if (signature == NULL) {

        ERR_raise(ERR_LIB_EVP, ERR_R_MALLOC_FAILURE);

        return NULL;

    }

    signature->lock = CRYPTO_THREAD_lock_new();

    if (signature->lock == NULL) {

        ERR_raise(ERR_LIB_EVP, ERR_R_MALLOC_FAILURE);

        OPENSSL_free(signature);

        return NULL;

    }

    signature->prov = prov;

    ossl_provider_up_ref(prov);

    signature->refcnt = 1;

    return signature;

}

static void *evp_signature_from_dispatch(int name_id,

                                         const OSSL_DISPATCH *fns,

                                         OSSL_PROVIDER *prov)

{

    EVP_SIGNATURE *signature = NULL;

    int ctxfncnt = 0, signfncnt = 0, verifyfncnt = 0, verifyrecfncnt = 0;

    int digsignfncnt = 0, digverifyfncnt = 0;

    int gparamfncnt = 0, sparamfncnt = 0, gmdparamfncnt = 0, smdparamfncnt = 0;

    if ((signature = evp_signature_new(prov)) == NULL) {

        ERR_raise(ERR_LIB_EVP, ERR_R_MALLOC_FAILURE);

        goto err;

    }

    signature->name_id = name_id;

    for (; fns->function_id != 0; fns++) {

        switch (fns->function_id) {

        case OSSL_FUNC_SIGNATURE_NEWCTX:

            if (signature->newctx != NULL)

                break;

            signature->newctx = OSSL_get_OP_signature_newctx(fns);

            ctxfncnt++;

            break;

        case OSSL_FUNC_SIGNATURE_SIGN_INIT:

            if (signature->sign_init != NULL)

                break;

            signature->sign_init = OSSL_get_OP_signature_sign_init(fns);

            signfncnt++;

            break;

        case OSSL_FUNC_SIGNATURE_SIGN:

            if (signature->sign != NULL)

                break;

            signature->sign = OSSL_get_OP_signature_sign(fns);

            signfncnt++;

            break;

        case OSSL_FUNC_SIGNATURE_VERIFY_INIT:

            if (signature->verify_init != NULL)

                break;

            signature->verify_init = OSSL_get_OP_signature_verify_init(fns);

            verifyfncnt++;

            break;

        case OSSL_FUNC_SIGNATURE_VERIFY:

            if (signature->verify != NULL)

                break;

            signature->verify = OSSL_get_OP_signature_verify(fns);

            verifyfncnt++;

            break;

        case OSSL_FUNC_SIGNATURE_VERIFY_RECOVER_INIT:

            if (signature->verify_recover_init != NULL)

                break;

            signature->verify_recover_init

                = OSSL_get_OP_signature_verify_recover_init(fns);

            verifyrecfncnt++;

            break;

        case OSSL_FUNC_SIGNATURE_VERIFY_RECOVER:

            if (signature->verify_recover != NULL)

                break;

            signature->verify_recover

                = OSSL_get_OP_signature_verify_recover(fns);

            verifyrecfncnt++;

            break;

        case OSSL_FUNC_SIGNATURE_DIGEST_SIGN_INIT:

            if (signature->digest_sign_init != NULL)

                break;

            signature->digest_sign_init

                = OSSL_get_OP_signature_digest_sign_init(fns);

            digsignfncnt++;

            break;

        case OSSL_FUNC_SIGNATURE_DIGEST_SIGN_UPDATE:

            if (signature->digest_sign_update != NULL)

                break;

            signature->digest_sign_update

                = OSSL_get_OP_signature_digest_sign_update(fns);

            digsignfncnt++;

            break;

        case OSSL_FUNC_SIGNATURE_DIGEST_SIGN_FINAL:

            if (signature->digest_sign_final != NULL)

                break;

            signature->digest_sign_final

                = OSSL_get_OP_signature_digest_sign_final(fns);

            digsignfncnt++;

            break;

        case OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_INIT:

            if (signature->digest_verify_init != NULL)

                break;

            signature->digest_verify_init

                = OSSL_get_OP_signature_digest_verify_init(fns);

            digverifyfncnt++;

            break;

        case OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_UPDATE:

            if (signature->digest_verify_update != NULL)

                break;

            signature->digest_verify_update

                = OSSL_get_OP_signature_digest_verify_update(fns);

            digverifyfncnt++;

            break;

        case OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_FINAL:

            if (signature->digest_verify_final != NULL)

                break;

            signature->digest_verify_final

                = OSSL_get_OP_signature_digest_verify_final(fns);

            digverifyfncnt++;

            break;

        case OSSL_FUNC_SIGNATURE_FREECTX:

            if (signature->freectx != NULL)

                break;

            signature->freectx = OSSL_get_OP_signature_freectx(fns);

            ctxfncnt++;

            break;

        case OSSL_FUNC_SIGNATURE_DUPCTX:

            if (signature->dupctx != NULL)

                break;

            signature->dupctx = OSSL_get_OP_signature_dupctx(fns);

            break;

        case OSSL_FUNC_SIGNATURE_GET_CTX_PARAMS:

            if (signature->get_ctx_params != NULL)

                break;

            signature->get_ctx_params

                = OSSL_get_OP_signature_get_ctx_params(fns);

            gparamfncnt++;

            break;

        case OSSL_FUNC_SIGNATURE_GETTABLE_CTX_PARAMS:

            if (signature->gettable_ctx_params != NULL)

                break;

            signature->gettable_ctx_params

                = OSSL_get_OP_signature_gettable_ctx_params(fns);

            gparamfncnt++;

            break;

        case OSSL_FUNC_SIGNATURE_SET_CTX_PARAMS:

            if (signature->set_ctx_params != NULL)

                break;

            signature->set_ctx_params

                = OSSL_get_OP_signature_set_ctx_params(fns);

            sparamfncnt++;

            break;

        case OSSL_FUNC_SIGNATURE_SETTABLE_CTX_PARAMS:

            if (signature->settable_ctx_params != NULL)

                break;

            signature->settable_ctx_params

                = OSSL_get_OP_signature_settable_ctx_params(fns);

            sparamfncnt++;

            break;

        case OSSL_FUNC_SIGNATURE_GET_CTX_MD_PARAMS:

            if (signature->get_ctx_md_params != NULL)

                break;

            signature->get_ctx_md_params

                = OSSL_get_OP_signature_get_ctx_md_params(fns);

            gmdparamfncnt++;

            break;

        case OSSL_FUNC_SIGNATURE_GETTABLE_CTX_MD_PARAMS:

            if (signature->gettable_ctx_md_params != NULL)

                break;

            signature->gettable_ctx_md_params

                = OSSL_get_OP_signature_gettable_ctx_md_params(fns);

            gmdparamfncnt++;

            break;

        case OSSL_FUNC_SIGNATURE_SET_CTX_MD_PARAMS:

            if (signature->set_ctx_md_params != NULL)

                break;

            signature->set_ctx_md_params

                = OSSL_get_OP_signature_set_ctx_md_params(fns);

            smdparamfncnt++;

            break;

        case OSSL_FUNC_SIGNATURE_SETTABLE_CTX_MD_PARAMS:

            if (signature->settable_ctx_md_params != NULL)

                break;

            signature->settable_ctx_md_params

                = OSSL_get_OP_signature_settable_ctx_md_params(fns);

            smdparamfncnt++;

            break;

        }

    }

    if (ctxfncnt != 2

        || (signfncnt == 0

            && verifyfncnt == 0

            && verifyrecfncnt == 0

            && digsignfncnt == 0

            && digverifyfncnt == 0)

        || (signfncnt != 0 && signfncnt != 2)

        || (verifyfncnt != 0 && verifyfncnt != 2)

        || (verifyrecfncnt != 0 && verifyrecfncnt != 2)

        || (digsignfncnt != 0 && digsignfncnt != 3)

        || (digverifyfncnt != 0 && digverifyfncnt != 3)

        || (gparamfncnt != 0 && gparamfncnt != 2)

        || (sparamfncnt != 0 && sparamfncnt != 2)

        || (gmdparamfncnt != 0 && gmdparamfncnt != 2)

        || (smdparamfncnt != 0 && smdparamfncnt != 2)) {

        /*

         * In order to be a consistent set of functions we must have at least

         * a set of context functions (newctx and freectx) as well as a set of

         * "signature" functions:

         *  (sign_init, sign) or

         *  (verify_init verify) or

         *  (verify_recover_init, verify_recover) or

         *  (digest_sign_init, digest_sign_update, digest_sign_final) or

         *  (digest_verify_init, digest_verify_update, digest_verify_final).

         *

         * set_ctx_params and settable_ctx_params are optional, but if one of

         * them is present then the other one must also be present. The same

         * applies to get_ctx_params and gettable_ctx_params. The same rules

         * apply to the "md_params" functions. The dupctx function is optional.

         */

        ERR_raise(ERR_LIB_EVP, EVP_R_INVALID_PROVIDER_FUNCTIONS);

        goto err;

    }

    return signature;

 err:

    EVP_SIGNATURE_free(signature);

    return NULL;

}

void EVP_SIGNATURE_free(EVP_SIGNATURE *signature)

{

    if (signature != NULL) {

        int i;

        CRYPTO_DOWN_REF(&signature->refcnt, &i, signature->lock);

        if (i > 0)

            return;

        ossl_provider_free(signature->prov);

        CRYPTO_THREAD_lock_free(signature->lock);

        OPENSSL_free(signature);

    }

}

int EVP_SIGNATURE_up_ref(EVP_SIGNATURE *signature)

{

    int ref = 0;

    CRYPTO_UP_REF(&signature->refcnt, &ref, signature->lock);

    return 1;

}

OSSL_PROVIDER *EVP_SIGNATURE_provider(const EVP_SIGNATURE *signature)

{

    return signature->prov;

}

EVP_SIGNATURE *EVP_SIGNATURE_fetch(OPENSSL_CTX *ctx, const char *algorithm,

                                   const char *properties)

{

    return evp_generic_fetch(ctx, OSSL_OP_SIGNATURE, algorithm, properties,

                             evp_signature_from_dispatch,

                             (int (*)(void *))EVP_SIGNATURE_up_ref,

                             (void (*)(void *))EVP_SIGNATURE_free);

}

int EVP_SIGNATURE_is_a(const EVP_SIGNATURE *signature, const char *name)

{

    return evp_is_a(signature->prov, signature->name_id, NULL, name);

}

int EVP_SIGNATURE_number(const EVP_SIGNATURE *signature)

{

    return signature->name_id;

}

void EVP_SIGNATURE_do_all_provided(OPENSSL_CTX *libctx,

                                   void (*fn)(EVP_SIGNATURE *signature,

                                              void *arg),

                                   void *arg)

{

    evp_generic_do_all(libctx, OSSL_OP_SIGNATURE,

                       (void (*)(void *, void *))fn, arg,

                       evp_signature_from_dispatch,

                       (void (*)(void *))EVP_SIGNATURE_free);

}

void EVP_SIGNATURE_names_do_all(const EVP_SIGNATURE *signature,

                                void (*fn)(const char *name, void *data),

                                void *data)

{

    if (signature->prov != NULL)

        evp_names_do_all(signature->prov, signature->name_id, fn, data);

}

static int evp_pkey_signature_init(EVP_PKEY_CTX *ctx, int operation)

{

    int ret = 0;

    void *provkey = NULL;

    EVP_SIGNATURE *signature = NULL;

    EVP_KEYMGMT *tmp_keymgmt = NULL;

    const char *supported_sig = NULL;

    if (ctx == NULL) {

        EVPerr(0, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);

        return -2;

    }

    evp_pkey_ctx_free_old_ops(ctx);

    ctx->operation = operation;

    /*

     * TODO when we stop falling back to legacy, this and the ERR_pop_to_mark()

     * calls can be removed.

     */

    ERR_set_mark();

    if (ctx->keytype == NULL)

        goto legacy;

    /* Ensure that the key is provided.  If not, go legacy */

    tmp_keymgmt = ctx->keymgmt;

    provkey = evp_pkey_make_provided(ctx->pkey, ctx->libctx,

                                     &tmp_keymgmt, ctx->propquery);

    if (provkey == NULL)

        goto legacy;

    if (!EVP_KEYMGMT_up_ref(tmp_keymgmt)) {

        ERR_clear_last_mark();

        ERR_raise(ERR_LIB_EVP, EVP_R_INITIALIZATION_ERROR);

        goto err;

    }

    EVP_KEYMGMT_free(ctx->keymgmt);

    ctx->keymgmt = tmp_keymgmt;

    if (ctx->keymgmt->query_operation_name != NULL)

        supported_sig = ctx->keymgmt->query_operation_name(OSSL_OP_SIGNATURE);

    /*

     * If we didn't get a supported sig, assume there is one with the

     * same name as the key type.

     */

    if (supported_sig == NULL)

        supported_sig = ctx->keytype;

    /*

     * Because we cleared out old ops, we shouldn't need to worry about

     * checking if signature is already there.

     */

    signature =

        EVP_SIGNATURE_fetch(ctx->libctx, supported_sig, ctx->propquery);

    if (signature == NULL

        || (EVP_KEYMGMT_provider(ctx->keymgmt)

            != EVP_SIGNATURE_provider(signature))) {

        /*

         * We don't need to free ctx->keymgmt here, as it's not necessarily

         * tied to this operation.  It will be freed by EVP_PKEY_CTX_free().

         */

        EVP_SIGNATURE_free(signature);

        goto legacy;

    }

    /*

     * TODO remove this when legacy is gone

     * If we don't have the full support we need with provided methods,

     * let's go see if legacy does.

     */

    ERR_pop_to_mark();

    /* No more legacy from here down to legacy: */

    ctx->op.sig.signature = signature;

    ctx->op.sig.sigprovctx = signature->newctx(ossl_provider_ctx(signature->prov));

    if (ctx->op.sig.sigprovctx == NULL) {

        /* The provider key can stay in the cache */

        EVPerr(0, EVP_R_INITIALIZATION_ERROR);

        goto err;

    }

    switch (operation) {

    case EVP_PKEY_OP_SIGN:

        if (signature->sign_init == NULL) {

            EVPerr(0, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);

            ret = -2;

            goto err;

        }

        ret = signature->sign_init(ctx->op.sig.sigprovctx, provkey);

        break;

    case EVP_PKEY_OP_VERIFY:

        if (signature->verify_init == NULL) {

            EVPerr(0, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);

            ret = -2;

            goto err;

        }

        ret = signature->verify_init(ctx->op.sig.sigprovctx, provkey);

        break;

    case EVP_PKEY_OP_VERIFYRECOVER:

        if (signature->verify_recover_init == NULL) {

            EVPerr(0, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);

            ret = -2;

            goto err;

        }

        ret = signature->verify_recover_init(ctx->op.sig.sigprovctx, provkey);

        break;

    default:

        EVPerr(0, EVP_R_INITIALIZATION_ERROR);

        goto err;

    }

    if (ret <= 0) {

        signature->freectx(ctx->op.sig.sigprovctx);

        ctx->op.sig.sigprovctx = NULL;

        goto err;

    }

    return 1;

 legacy:

    /*

     * TODO remove this when legacy is gone

     * If we don't have the full support we need with provided methods,

     * let's go see if legacy does.

     */

    ERR_pop_to_mark();

    if (ctx->pmeth == NULL

            || (operation == EVP_PKEY_OP_SIGN && ctx->pmeth->sign == NULL)

            || (operation == EVP_PKEY_OP_VERIFY && ctx->pmeth->verify == NULL)

            || (operation == EVP_PKEY_OP_VERIFYRECOVER

                && ctx->pmeth->verify_recover == NULL)) {

        EVPerr(0, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);

        return -2;

    }

    switch (operation) {

    case EVP_PKEY_OP_SIGN:

        if (ctx->pmeth->sign_init == NULL)

            return 1;

        ret = ctx->pmeth->sign_init(ctx);

        break;

    case EVP_PKEY_OP_VERIFY:

        if (ctx->pmeth->verify_init == NULL)

            return 1;

        ret = ctx->pmeth->verify_init(ctx);

        break;

    case EVP_PKEY_OP_VERIFYRECOVER:

        if (ctx->pmeth->verify_recover_init == NULL)

            return 1;

        ret = ctx->pmeth->verify_recover_init(ctx);

        break;

    default:

        EVPerr(0, EVP_R_INITIALIZATION_ERROR);

        goto err;

    }

    if (ret <= 0)

        goto err;

    return ret;

 err:

    ctx->operation = EVP_PKEY_OP_UNDEFINED;

    return ret;

}

int EVP_PKEY_sign_init(EVP_PKEY_CTX *ctx)

{

    return evp_pkey_signature_init(ctx, EVP_PKEY_OP_SIGN);

}

int EVP_PKEY_sign(EVP_PKEY_CTX *ctx,

                  unsigned char *sig, size_t *siglen,

                  const unsigned char *tbs, size_t tbslen)

{

    int ret;

    if (ctx == NULL) {

        EVPerr(0, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);

        return -2;

    }

    if (ctx->operation != EVP_PKEY_OP_SIGN) {

        EVPerr(0, EVP_R_OPERATON_NOT_INITIALIZED);

        return -1;

    }

    if (ctx->op.sig.sigprovctx == NULL)

        goto legacy;

    ret = ctx->op.sig.signature->sign(ctx->op.sig.sigprovctx, sig, siglen,

                                      SIZE_MAX, tbs, tbslen);

    return ret;

 legacy:

    if (ctx->pmeth == NULL || ctx->pmeth->sign == NULL) {

        EVPerr(0, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);

        return -2;

    }

    M_check_autoarg(ctx, sig, siglen, EVP_F_EVP_PKEY_SIGN)

        return ctx->pmeth->sign(ctx, sig, siglen, tbs, tbslen);

}

int EVP_PKEY_verify_init(EVP_PKEY_CTX *ctx)

{

    return evp_pkey_signature_init(ctx, EVP_PKEY_OP_VERIFY);

}

int EVP_PKEY_verify(EVP_PKEY_CTX *ctx,

                    const unsigned char *sig, size_t siglen,

                    const unsigned char *tbs, size_t tbslen)

{

    int ret;

    if (ctx == NULL) {

        EVPerr(0, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);

        return -2;

    }

    if (ctx->operation != EVP_PKEY_OP_VERIFY) {

        EVPerr(0, EVP_R_OPERATON_NOT_INITIALIZED);

        return -1;

    }

    if (ctx->op.sig.sigprovctx == NULL)

        goto legacy;

    ret = ctx->op.sig.signature->verify(ctx->op.sig.sigprovctx, sig, siglen,

                                        tbs, tbslen);

    return ret;

 legacy:

    if (ctx->pmeth == NULL || ctx->pmeth->verify == NULL) {

        EVPerr(0, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);

        return -2;

    }

    return ctx->pmeth->verify(ctx, sig, siglen, tbs, tbslen);

}

int EVP_PKEY_verify_recover_init(EVP_PKEY_CTX *ctx)

{

    return evp_pkey_signature_init(ctx, EVP_PKEY_OP_VERIFYRECOVER);

}

int EVP_PKEY_verify_recover(EVP_PKEY_CTX *ctx,

                            unsigned char *rout, size_t *routlen,

                            const unsigned char *sig, size_t siglen)

{

    int ret;

    if (ctx == NULL) {

        EVPerr(0, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);

        return -2;

    }

    if (ctx->operation != EVP_PKEY_OP_VERIFYRECOVER) {

        EVPerr(0, EVP_R_OPERATON_NOT_INITIALIZED);

        return -1;

    }

    if (ctx->op.sig.sigprovctx == NULL)

        goto legacy;

    ret = ctx->op.sig.signature->verify_recover(ctx->op.sig.sigprovctx, rout,

                                                routlen,

                                                (rout == NULL ? 0 : *routlen),

                                                sig, siglen);

    return ret;

 legacy:

    if (ctx->pmeth == NULL || ctx->pmeth->verify_recover == NULL) {

        EVPerr(0, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);

        return -2;

    }

    M_check_autoarg(ctx, rout, routlen, EVP_F_EVP_PKEY_VERIFY_RECOVER)

        return ctx->pmeth->verify_recover(ctx, rout, routlen, sig, siglen);

}