/*

 * Copyright 2015-2018 The OpenSSL Project Authors. All Rights Reserved.

 *

 * Licensed under the OpenSSL license (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

 */

/*

 * This is the OSSLTEST engine. It provides deliberately crippled digest

 * implementations for test purposes. It is highly insecure and must NOT be

 * used for any purpose except testing

 */

#include <stdio.h>

#include <string.h>

#include <openssl/engine.h>

#include <openssl/sha.h>

#include <openssl/md5.h>

#include <openssl/rsa.h>

#include <openssl/evp.h>

#include <openssl/modes.h>

#include <openssl/aes.h>

#include <openssl/rand.h>

#include <openssl/crypto.h>

#include "e_ossltest_err.c"

/* Engine Id and Name */

static const char *engine_ossltest_id = "ossltest";

static const char *engine_ossltest_name = "OpenSSL Test engine support";

/* Engine Lifetime functions */

static int ossltest_destroy(ENGINE *e);

static int ossltest_init(ENGINE *e);

static int ossltest_finish(ENGINE *e);

void ENGINE_load_ossltest(void);

/* Set up digests */

static int ossltest_digests(ENGINE *e, const EVP_MD **digest,

                          const int **nids, int nid);

static const RAND_METHOD *ossltest_rand_method(void);

/* MD5 */

static int digest_md5_init(EVP_MD_CTX *ctx);

static int digest_md5_update(EVP_MD_CTX *ctx, const void *data,

                             size_t count);

static int digest_md5_final(EVP_MD_CTX *ctx, unsigned char *md);

static EVP_MD *_hidden_md5_md = NULL;

static const EVP_MD *digest_md5(void)

{

    if (_hidden_md5_md == NULL) {

        EVP_MD *md;

        if ((md = EVP_MD_meth_new(NID_md5, NID_md5WithRSAEncryption)) == NULL

            || !EVP_MD_meth_set_result_size(md, MD5_DIGEST_LENGTH)

            || !EVP_MD_meth_set_input_blocksize(md, MD5_CBLOCK)

            || !EVP_MD_meth_set_app_datasize(md,

                                             sizeof(EVP_MD *) + sizeof(MD5_CTX))

            || !EVP_MD_meth_set_flags(md, 0)

            || !EVP_MD_meth_set_init(md, digest_md5_init)

            || !EVP_MD_meth_set_update(md, digest_md5_update)

            || !EVP_MD_meth_set_final(md, digest_md5_final)) {

            EVP_MD_meth_free(md);

            md = NULL;

        }

        _hidden_md5_md = md;

    }

    return _hidden_md5_md;

}

/* SHA1 */

static int digest_sha1_init(EVP_MD_CTX *ctx);

static int digest_sha1_update(EVP_MD_CTX *ctx, const void *data,

                              size_t count);

static int digest_sha1_final(EVP_MD_CTX *ctx, unsigned char *md);

static EVP_MD *_hidden_sha1_md = NULL;

static const EVP_MD *digest_sha1(void)

{

    if (_hidden_sha1_md == NULL) {

        EVP_MD *md;

        if ((md = EVP_MD_meth_new(NID_sha1, NID_sha1WithRSAEncryption)) == NULL

            || !EVP_MD_meth_set_result_size(md, SHA_DIGEST_LENGTH)

            || !EVP_MD_meth_set_input_blocksize(md, SHA_CBLOCK)

            || !EVP_MD_meth_set_app_datasize(md,

                                             sizeof(EVP_MD *) + sizeof(SHA_CTX))

            || !EVP_MD_meth_set_flags(md, EVP_MD_FLAG_DIGALGID_ABSENT)

            || !EVP_MD_meth_set_init(md, digest_sha1_init)

            || !EVP_MD_meth_set_update(md, digest_sha1_update)

            || !EVP_MD_meth_set_final(md, digest_sha1_final)) {

            EVP_MD_meth_free(md);

            md = NULL;

        }

        _hidden_sha1_md = md;

    }

    return _hidden_sha1_md;

}

/* SHA256 */

static int digest_sha256_init(EVP_MD_CTX *ctx);

static int digest_sha256_update(EVP_MD_CTX *ctx, const void *data,

                                size_t count);

static int digest_sha256_final(EVP_MD_CTX *ctx, unsigned char *md);

static EVP_MD *_hidden_sha256_md = NULL;

static const EVP_MD *digest_sha256(void)

{

    if (_hidden_sha256_md == NULL) {

        EVP_MD *md;

        if ((md = EVP_MD_meth_new(NID_sha256, NID_sha256WithRSAEncryption)) == NULL

            || !EVP_MD_meth_set_result_size(md, SHA256_DIGEST_LENGTH)

            || !EVP_MD_meth_set_input_blocksize(md, SHA256_CBLOCK)

            || !EVP_MD_meth_set_app_datasize(md,

                                             sizeof(EVP_MD *) + sizeof(SHA256_CTX))

            || !EVP_MD_meth_set_flags(md, EVP_MD_FLAG_DIGALGID_ABSENT)

            || !EVP_MD_meth_set_init(md, digest_sha256_init)

            || !EVP_MD_meth_set_update(md, digest_sha256_update)

            || !EVP_MD_meth_set_final(md, digest_sha256_final)) {

            EVP_MD_meth_free(md);

            md = NULL;

        }

        _hidden_sha256_md = md;

    }

    return _hidden_sha256_md;

}

/* SHA384/SHA512 */

static int digest_sha384_init(EVP_MD_CTX *ctx);

static int digest_sha512_init(EVP_MD_CTX *ctx);

static int digest_sha512_update(EVP_MD_CTX *ctx, const void *data,

                                size_t count);

static int digest_sha384_final(EVP_MD_CTX *ctx, unsigned char *md);

static int digest_sha512_final(EVP_MD_CTX *ctx, unsigned char *md);

static EVP_MD *_hidden_sha384_md = NULL;

static const EVP_MD *digest_sha384(void)

{

    if (_hidden_sha384_md == NULL) {

        EVP_MD *md;

        if ((md = EVP_MD_meth_new(NID_sha384, NID_sha384WithRSAEncryption)) == NULL

            || !EVP_MD_meth_set_result_size(md, SHA384_DIGEST_LENGTH)

            || !EVP_MD_meth_set_input_blocksize(md, SHA512_CBLOCK)

            || !EVP_MD_meth_set_app_datasize(md,

                                             sizeof(EVP_MD *) + sizeof(SHA512_CTX))

            || !EVP_MD_meth_set_flags(md, EVP_MD_FLAG_DIGALGID_ABSENT)

            || !EVP_MD_meth_set_init(md, digest_sha384_init)

            || !EVP_MD_meth_set_update(md, digest_sha512_update)

            || !EVP_MD_meth_set_final(md, digest_sha384_final)) {

            EVP_MD_meth_free(md);

            md = NULL;

        }

        _hidden_sha384_md = md;

    }

    return _hidden_sha384_md;

}

static EVP_MD *_hidden_sha512_md = NULL;

static const EVP_MD *digest_sha512(void)

{

    if (_hidden_sha512_md == NULL) {

        EVP_MD *md;

        if ((md = EVP_MD_meth_new(NID_sha512, NID_sha512WithRSAEncryption)) == NULL

            || !EVP_MD_meth_set_result_size(md, SHA512_DIGEST_LENGTH)

            || !EVP_MD_meth_set_input_blocksize(md, SHA512_CBLOCK)

            || !EVP_MD_meth_set_app_datasize(md,

                                             sizeof(EVP_MD *) + sizeof(SHA512_CTX))

            || !EVP_MD_meth_set_flags(md, EVP_MD_FLAG_DIGALGID_ABSENT)

            || !EVP_MD_meth_set_init(md, digest_sha512_init)

            || !EVP_MD_meth_set_update(md, digest_sha512_update)

            || !EVP_MD_meth_set_final(md, digest_sha512_final)) {

            EVP_MD_meth_free(md);

            md = NULL;

        }

        _hidden_sha512_md = md;

    }

    return _hidden_sha512_md;

}

static void destroy_digests(void)

{

    EVP_MD_meth_free(_hidden_md5_md);

    _hidden_md5_md = NULL;

    EVP_MD_meth_free(_hidden_sha1_md);

    _hidden_sha1_md = NULL;

    EVP_MD_meth_free(_hidden_sha256_md);

    _hidden_sha256_md = NULL;

    EVP_MD_meth_free(_hidden_sha384_md);

    _hidden_sha384_md = NULL;

    EVP_MD_meth_free(_hidden_sha512_md);

    _hidden_sha512_md = NULL;

}

static int ossltest_digest_nids(const int **nids)

{

    static int digest_nids[6] = { 0, 0, 0, 0, 0, 0 };

    static int pos = 0;

    static int init = 0;

    if (!init) {

        const EVP_MD *md;

        if ((md = digest_md5()) != NULL)

            digest_nids[pos++] = EVP_MD_type(md);

        if ((md = digest_sha1()) != NULL)

            digest_nids[pos++] = EVP_MD_type(md);

        if ((md = digest_sha256()) != NULL)

            digest_nids[pos++] = EVP_MD_type(md);

        if ((md = digest_sha384()) != NULL)

            digest_nids[pos++] = EVP_MD_type(md);

        if ((md = digest_sha512()) != NULL)

            digest_nids[pos++] = EVP_MD_type(md);

        digest_nids[pos] = 0;

        init = 1;

    }

    *nids = digest_nids;

    return pos;

}

/* Setup ciphers */

static int ossltest_ciphers(ENGINE *, const EVP_CIPHER **,

                            const int **, int);

static int ossltest_cipher_nids[] = {

    NID_aes_128_cbc, NID_aes_128_gcm, 0

};

/* AES128 */

int ossltest_aes128_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key,

                             const unsigned char *iv, int enc);

int ossltest_aes128_cbc_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,

                               const unsigned char *in, size_t inl);

int ossltest_aes128_gcm_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key,

                             const unsigned char *iv, int enc);

int ossltest_aes128_gcm_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,

                               const unsigned char *in, size_t inl);

static int ossltest_aes128_gcm_ctrl(EVP_CIPHER_CTX *ctx, int type, int arg,

                                    void *ptr);

static EVP_CIPHER *_hidden_aes_128_cbc = NULL;

static const EVP_CIPHER *ossltest_aes_128_cbc(void)

{

    if (_hidden_aes_128_cbc == NULL

        && ((_hidden_aes_128_cbc = EVP_CIPHER_meth_new(NID_aes_128_cbc,

                                                       16 /* block size */,

                                                       16 /* key len */)) == NULL

            || !EVP_CIPHER_meth_set_iv_length(_hidden_aes_128_cbc,16)

            || !EVP_CIPHER_meth_set_flags(_hidden_aes_128_cbc,

                                          EVP_CIPH_FLAG_DEFAULT_ASN1

                                          | EVP_CIPH_CBC_MODE)

            || !EVP_CIPHER_meth_set_init(_hidden_aes_128_cbc,

                                         ossltest_aes128_init_key)

            || !EVP_CIPHER_meth_set_do_cipher(_hidden_aes_128_cbc,

                                              ossltest_aes128_cbc_cipher)

            || !EVP_CIPHER_meth_set_impl_ctx_size(_hidden_aes_128_cbc,

                                                  EVP_CIPHER_impl_ctx_size(EVP_aes_128_cbc())))) {

        EVP_CIPHER_meth_free(_hidden_aes_128_cbc);

        _hidden_aes_128_cbc = NULL;

    }

    return _hidden_aes_128_cbc;

}

static EVP_CIPHER *_hidden_aes_128_gcm = NULL;

#define AES_GCM_FLAGS   (EVP_CIPH_FLAG_DEFAULT_ASN1 \

                | EVP_CIPH_CUSTOM_IV | EVP_CIPH_FLAG_CUSTOM_CIPHER \

                | EVP_CIPH_ALWAYS_CALL_INIT | EVP_CIPH_CTRL_INIT \

                | EVP_CIPH_CUSTOM_COPY |EVP_CIPH_FLAG_AEAD_CIPHER \

                | EVP_CIPH_GCM_MODE)

static const EVP_CIPHER *ossltest_aes_128_gcm(void)

{

    if (_hidden_aes_128_gcm == NULL

        && ((_hidden_aes_128_gcm = EVP_CIPHER_meth_new(NID_aes_128_gcm,

                                                       1 /* block size */,

                                                       16 /* key len */)) == NULL

            || !EVP_CIPHER_meth_set_iv_length(_hidden_aes_128_gcm,12)

            || !EVP_CIPHER_meth_set_flags(_hidden_aes_128_gcm, AES_GCM_FLAGS)

            || !EVP_CIPHER_meth_set_init(_hidden_aes_128_gcm,

                                         ossltest_aes128_gcm_init_key)

            || !EVP_CIPHER_meth_set_do_cipher(_hidden_aes_128_gcm,

                                              ossltest_aes128_gcm_cipher)

            || !EVP_CIPHER_meth_set_ctrl(_hidden_aes_128_gcm,

                                              ossltest_aes128_gcm_ctrl)

            || !EVP_CIPHER_meth_set_impl_ctx_size(_hidden_aes_128_gcm,

                              EVP_CIPHER_impl_ctx_size(EVP_aes_128_gcm())))) {

        EVP_CIPHER_meth_free(_hidden_aes_128_gcm);

        _hidden_aes_128_gcm = NULL;

    }

    return _hidden_aes_128_gcm;

}

static void destroy_ciphers(void)

{

    EVP_CIPHER_meth_free(_hidden_aes_128_cbc);

    EVP_CIPHER_meth_free(_hidden_aes_128_gcm);

    _hidden_aes_128_cbc = NULL;

}

static int bind_ossltest(ENGINE *e)

{

    /* Ensure the ossltest error handling is set up */

    ERR_load_OSSLTEST_strings();

    if (!ENGINE_set_id(e, engine_ossltest_id)

        || !ENGINE_set_name(e, engine_ossltest_name)

        || !ENGINE_set_digests(e, ossltest_digests)

        || !ENGINE_set_ciphers(e, ossltest_ciphers)

        || !ENGINE_set_RAND(e, ossltest_rand_method())

        || !ENGINE_set_destroy_function(e, ossltest_destroy)

        || !ENGINE_set_init_function(e, ossltest_init)

        || !ENGINE_set_finish_function(e, ossltest_finish)) {

        OSSLTESTerr(OSSLTEST_F_BIND_OSSLTEST, OSSLTEST_R_INIT_FAILED);

        return 0;

    }

    return 1;

}

#ifndef OPENSSL_NO_DYNAMIC_ENGINE

static int bind_helper(ENGINE *e, const char *id)

{

    if (id && (strcmp(id, engine_ossltest_id) != 0))

        return 0;

    if (!bind_ossltest(e))

        return 0;

    return 1;

}

IMPLEMENT_DYNAMIC_CHECK_FN()

    IMPLEMENT_DYNAMIC_BIND_FN(bind_helper)

#endif

static ENGINE *engine_ossltest(void)

{

    ENGINE *ret = ENGINE_new();

    if (ret == NULL)

        return NULL;

    if (!bind_ossltest(ret)) {

        ENGINE_free(ret);

        return NULL;

    }

    return ret;

}

void ENGINE_load_ossltest(void)

{

    /* Copied from eng_[openssl|dyn].c */

    ENGINE *toadd = engine_ossltest();

    if (!toadd)

        return;

    ENGINE_add(toadd);

    ENGINE_free(toadd);

    ERR_clear_error();

}

static int ossltest_init(ENGINE *e)

{

    return 1;

}

static int ossltest_finish(ENGINE *e)

{

    return 1;

}

static int ossltest_destroy(ENGINE *e)

{

    destroy_digests();

    destroy_ciphers();

    ERR_unload_OSSLTEST_strings();

    return 1;

}

static int ossltest_digests(ENGINE *e, const EVP_MD **digest,

                          const int **nids, int nid)

{

    int ok = 1;

    if (!digest) {

        /* We are returning a list of supported nids */

        return ossltest_digest_nids(nids);

    }

    /* We are being asked for a specific digest */

    switch (nid) {

    case NID_md5:

        *digest = digest_md5();

        break;

    case NID_sha1:

        *digest = digest_sha1();

        break;

    case NID_sha256:

        *digest = digest_sha256();

        break;

    case NID_sha384:

        *digest = digest_sha384();

        break;

    case NID_sha512:

        *digest = digest_sha512();

        break;

    default:

        ok = 0;

        *digest = NULL;

        break;

    }

    return ok;

}

static int ossltest_ciphers(ENGINE *e, const EVP_CIPHER **cipher,

                          const int **nids, int nid)

{

    int ok = 1;

    if (!cipher) {

        /* We are returning a list of supported nids */

        *nids = ossltest_cipher_nids;

        return (sizeof(ossltest_cipher_nids) - 1)

               / sizeof(ossltest_cipher_nids[0]);

    }

    /* We are being asked for a specific cipher */

    switch (nid) {

    case NID_aes_128_cbc:

        *cipher = ossltest_aes_128_cbc();

        break;

    case NID_aes_128_gcm:

        *cipher = ossltest_aes_128_gcm();

        break;

    default:

        ok = 0;

        *cipher = NULL;

        break;

    }

    return ok;

}

static void fill_known_data(unsigned char *md, unsigned int len)

{

    unsigned int i;

    for (i=0; i

        md[i] = (unsigned char)(i & 0xff);

    }

}

/*

 * MD5 implementation. We go through the motions of doing MD5 by deferring to

 * the standard implementation. Then we overwrite the result with a will defined

 * value, so that all "MD5" digests using the test engine always end up with

 * the same value.

 */

#undef data

#define data(ctx) ((MD5_CTX *)EVP_MD_CTX_md_data(ctx))

static int digest_md5_init(EVP_MD_CTX *ctx)

{

    return MD5_Init(data(ctx));

}

static int digest_md5_update(EVP_MD_CTX *ctx, const void *data,

                             size_t count)

{

    return MD5_Update(data(ctx), data, (size_t)count);

}

static int digest_md5_final(EVP_MD_CTX *ctx, unsigned char *md)

{

    int ret;

    ret = MD5_Final(md, data(ctx));

    if (ret > 0) {

        fill_known_data(md, MD5_DIGEST_LENGTH);

    }

    return ret;

}

/*

 * SHA1 implementation.

 */

#undef data

#define data(ctx) ((SHA_CTX *)EVP_MD_CTX_md_data(ctx))

static int digest_sha1_init(EVP_MD_CTX *ctx)

{

    return SHA1_Init(data(ctx));

}

static int digest_sha1_update(EVP_MD_CTX *ctx, const void *data,

                              size_t count)

{

    return SHA1_Update(data(ctx), data, (size_t)count);

}

static int digest_sha1_final(EVP_MD_CTX *ctx, unsigned char *md)

{

    int ret;

    ret = SHA1_Final(md, data(ctx));

    if (ret > 0) {

        fill_known_data(md, SHA_DIGEST_LENGTH);

    }

    return ret;

}

/*

 * SHA256 implementation.

 */

#undef data

#define data(ctx) ((SHA256_CTX *)EVP_MD_CTX_md_data(ctx))

static int digest_sha256_init(EVP_MD_CTX *ctx)

{

    return SHA256_Init(data(ctx));

}

static int digest_sha256_update(EVP_MD_CTX *ctx, const void *data,

                                size_t count)

{

    return SHA256_Update(data(ctx), data, (size_t)count);

}

static int digest_sha256_final(EVP_MD_CTX *ctx, unsigned char *md)

{

    int ret;

    ret = SHA256_Final(md, data(ctx));

    if (ret > 0) {

        fill_known_data(md, SHA256_DIGEST_LENGTH);

    }

    return ret;

}

/*

 * SHA384/512 implementation.

 */

#undef data

#define data(ctx) ((SHA512_CTX *)EVP_MD_CTX_md_data(ctx))

static int digest_sha384_init(EVP_MD_CTX *ctx)

{

    return SHA384_Init(data(ctx));

}

static int digest_sha512_init(EVP_MD_CTX *ctx)

{

    return SHA512_Init(data(ctx));

}

static int digest_sha512_update(EVP_MD_CTX *ctx, const void *data,

                                size_t count)

{

    return SHA512_Update(data(ctx), data, (size_t)count);

}

static int digest_sha384_final(EVP_MD_CTX *ctx, unsigned char *md)

{

    int ret;

    /* Actually uses SHA512_Final! */

    ret = SHA512_Final(md, data(ctx));

    if (ret > 0) {

        fill_known_data(md, SHA384_DIGEST_LENGTH);

    }

    return ret;

}

static int digest_sha512_final(EVP_MD_CTX *ctx, unsigned char *md)

{

    int ret;

    ret = SHA512_Final(md, data(ctx));

    if (ret > 0) {

        fill_known_data(md, SHA512_DIGEST_LENGTH);

    }

    return ret;

}

/*

 * AES128 Implementation

 */

int ossltest_aes128_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key,

                             const unsigned char *iv, int enc)

{

    return EVP_CIPHER_meth_get_init(EVP_aes_128_cbc()) (ctx, key, iv, enc);

}

int ossltest_aes128_cbc_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,

                               const unsigned char *in, size_t inl)

{

    unsigned char *tmpbuf;

    int ret;

    tmpbuf = OPENSSL_malloc(inl);

    /* OPENSSL_malloc will return NULL if inl == 0 */

    if (tmpbuf == NULL && inl > 0)

        return -1;

    /* Remember what we were asked to encrypt */

    if (tmpbuf != NULL)

        memcpy(tmpbuf, in, inl);

    /* Go through the motions of encrypting it */

    ret = EVP_CIPHER_meth_get_do_cipher(EVP_aes_128_cbc())(ctx, out, in, inl);

    /* Throw it all away and just use the plaintext as the output */

    if (tmpbuf != NULL)

        memcpy(out, tmpbuf, inl);

    OPENSSL_free(tmpbuf);

    return ret;

}

int ossltest_aes128_gcm_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key,

                             const unsigned char *iv, int enc)

{

    return EVP_CIPHER_meth_get_init(EVP_aes_128_gcm()) (ctx, key, iv, enc);

}

int ossltest_aes128_gcm_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,

                               const unsigned char *in, size_t inl)

{

    unsigned char *tmpbuf = OPENSSL_malloc(inl);

    /* OPENSSL_malloc will return NULL if inl == 0 */

    if (tmpbuf == NULL && inl > 0)

        return -1;

    /* Remember what we were asked to encrypt */

    if (tmpbuf != NULL)

        memcpy(tmpbuf, in, inl);

    /* Go through the motions of encrypting it */

    EVP_CIPHER_meth_get_do_cipher(EVP_aes_128_gcm())(ctx, out, in, inl);

    /* Throw it all away and just use the plaintext as the output */

    if (tmpbuf != NULL && out != NULL)

        memcpy(out, tmpbuf, inl);

    OPENSSL_free(tmpbuf);

    return inl;

}

static int ossltest_aes128_gcm_ctrl(EVP_CIPHER_CTX *ctx, int type, int arg,

                                    void *ptr)

{

    /* Pass the ctrl down */

    int ret = EVP_CIPHER_meth_get_ctrl(EVP_aes_128_gcm())(ctx, type, arg, ptr);

    if (ret <= 0)

        return ret;

    switch(type) {

    case EVP_CTRL_AEAD_GET_TAG:

        /* Always give the same tag */

        memset(ptr, 0, EVP_GCM_TLS_TAG_LEN);

        break;

    default:

        break;

    }

    return 1;

}

static int ossltest_rand_bytes(unsigned char *buf, int num)

{

    unsigned char val = 1;

    while (--num >= 0)

        *buf++ = val++;

    return 1;

}

static int ossltest_rand_status(void)

{

    return 1;

}

static const RAND_METHOD *ossltest_rand_method(void)

{

    static RAND_METHOD osslt_rand_meth = {

        NULL,

        ossltest_rand_bytes,

        NULL,

        NULL,

        ossltest_rand_bytes,

        ossltest_rand_status

    };

    return &osslt_rand_meth;

}