C++ DH_generate_parameters_ex函數代碼示例

void openssl_dh_crypt()
{
	BIO *b;
	DH *d1, *d2;
	int i, len1, len2;
	unsigned char skey1[COMM_LEN], skey2[COMM_LEN];

	d1 = DH_new();
	d2 = DH_new();
	DH_generate_parameters_ex(d1, 64, DH_GENERATOR_2, NULL);
	DH_check(d1, &i);
	printf("\nDH key size: %d\n", DH_size(d1));
	DH_generate_key(d1);

	d2->p = BN_dup(d1->p);
	d2->g = BN_dup(d1->g);
	DH_generate_key(d2);
	DH_check_pub_key(d1, d1->pub_key, &i);
	len1 = DH_compute_key(skey1, d2->pub_key, d1);
	len2 = DH_compute_key(skey2, d1->pub_key, d2);
	if ((len1 != len2) || (memcmp(skey1, skey2, len1) != 0)) {
		printf("DH_compute_key err!\n");
		DH_free(d1);
		DH_free(d2);
		return;
	}

	b = BIO_new(BIO_s_file());
	BIO_set_fp(b, stdout, BIO_NOCLOSE);
	DHparams_print(b, d1);

	BIO_free(b);
	DH_free(d1);
	DH_free(d2);
}

DH * dif_hel_setup()
{
    DH * new_dh = DH_new();
    if ( !new_dh )
    {
	printf("%s \n","Error:Creating new dh");
	error();
    }
    if ( !DH_generate_parameters_ex(new_dh,2,DH_GENERATOR_2,0))
    {
	printf("%s \n","Error:Generating paramters");
	error();
    }
    int dh_code = 0;
    if( !DH_check(new_dh,&dh_code))
    {
	printf("%s \n", "Error:Dh_check failed");
	error();
    }
    if(!DH_generate_key(new_dh))
    {
	printf("%s \n", "Error:Generating key failed");
	error();
    }
    return new_dh;
}

/**
  Generates DH parameter.

  Given generator g, and length of prime number p in bits, this function generates p,
  and sets DH context according to value of g and p.

  Before this function can be invoked, pseudorandom number generator must be correctly
  initialized by RandomSeed().

  If DhContext is NULL, then return FALSE.
  If Prime is NULL, then return FALSE.

  @param[in, out]  DhContext    Pointer to the DH context.
  @param[in]       Generator    Value of generator.
  @param[in]       PrimeLength  Length in bits of prime to be generated.
  @param[out]      Prime        Pointer to the buffer to receive the generated prime number.

  @retval TRUE   DH parameter generation succeeded.
  @retval FALSE  Value of Generator is not supported.
  @retval FALSE  PRNG fails to generate random prime number with PrimeLength.

**/
BOOLEAN
EFIAPI
DhGenerateParameter (
  IN OUT  VOID   *DhContext,
  IN      UINTN  Generator,
  IN      UINTN  PrimeLength,
  OUT     UINT8  *Prime
  )
{
  BOOLEAN RetVal;
  BIGNUM  *BnP;

  //
  // Check input parameters.
  //
  if (DhContext == NULL || Prime == NULL || PrimeLength > INT_MAX) {
    return FALSE;
  }

  if (Generator != DH_GENERATOR_2 && Generator != DH_GENERATOR_5) {
    return FALSE;
  }

  RetVal = (BOOLEAN) DH_generate_parameters_ex (DhContext, (UINT32) PrimeLength, (UINT32) Generator, NULL);
  if (!RetVal) {
    return FALSE;
  }

  DH_get0_pqg (DhContext, (const BIGNUM **)&BnP, NULL, NULL);
  BN_bn2bin (BnP, Prime);

  return TRUE;
}

static void *
dh_blocking_gen(void *arg)
{
    struct dh_blocking_gen_arg *gen = (struct dh_blocking_gen_arg *)arg;
    gen->result = DH_generate_parameters_ex(gen->dh, gen->size, gen->gen, gen->cb);
    return 0;
}

int main(int arc, char *argv[])
{ 
	DH *dh = DH_new();

	BN_GENCB *(*cb)(BN_GENCB *, int, int);	
	cb = &callback;

	char buf[400];
	char *bufPtr = &buf[0];

	/* Load the human readable error strings for libcrypto */
	ERR_load_crypto_strings();
	/* Load all digest and cipher algorithms */
	OpenSSL_add_all_algorithms();
	/* Load config file, and other important initialisation */
	OPENSSL_config(NULL);

	/*
		use special PRNG if possible:
			* /dev/random
			* /dev/hwrng
			* ...
	*/

	/*
 		----------------------------	PARAMATER GEN	------------------------
	*/

	printf("start generation\n");
	DH_generate_parameters_ex(dh, 256, 2, NULL);
	printf("paramters DONE\n");

	if(dh->pub_key == NULL)
		printf("pubkey init to NULL\n");

	DH_generate_key(dh);
	printf("key DONE\n");
	bufPtr = BN_bn2hex(dh->p);
	printf ("prime    : %s\n", bufPtr);
	bufPtr = BN_bn2hex(dh->g);
	printf ("generator: %s\n", bufPtr);
	bufPtr = BN_bn2hex(dh->pub_key);
	printf ("pubkey   : %s\n", bufPtr);
	bufPtr = BN_bn2hex(dh->priv_key);
	printf ("privkey  : %s\n", bufPtr);

  /* Clean up */

  /* Removes all digests and ciphers */
  EVP_cleanup();

  /* if you omit the next, a small leak may be left when you make use of the BIO (low level API) for e.g. base64 transformations */
  CRYPTO_cleanup_all_ex_data();

  /* Remove error strings */
  ERR_free_strings();

  return 0;
}

static int pkey_dh_paramgen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey)
{
    DH *dh = NULL;
    DH_PKEY_CTX *dctx = ctx->data;
    BN_GENCB *pcb, cb;
    int ret;
    if (dctx->rfc5114_param) {
        switch (dctx->rfc5114_param) {
        case 1:
            dh = DH_get_1024_160();
            break;

        case 2:
            dh = DH_get_2048_224();
            break;

        case 3:
            dh = DH_get_2048_256();
            break;

        default:
            return -2;
        }
        EVP_PKEY_assign(pkey, EVP_PKEY_DHX, dh);
        return 1;
    }

    if (ctx->pkey_gencb) {
        pcb = &cb;
        evp_pkey_set_cb_translate(pcb, ctx);
    } else
        pcb = NULL;
#ifndef OPENSSL_NO_DSA
    if (dctx->use_dsa) {
        DSA *dsa_dh;
        dsa_dh = dsa_dh_generate(dctx, pcb);
        if (!dsa_dh)
            return 0;
        dh = DSA_dup_DH(dsa_dh);
        DSA_free(dsa_dh);
        if (!dh)
            return 0;
        EVP_PKEY_assign(pkey, EVP_PKEY_DHX, dh);
        return 1;
    }
#endif
    dh = DH_new();
    if (!dh)
        return 0;
    ret = DH_generate_parameters_ex(dh,
                                    dctx->prime_len, dctx->generator, pcb);

    if (ret)
        EVP_PKEY_assign_DH(pkey, dh);
    else
        DH_free(dh);
    return ret;
}

void OpenSSLGenerateDHParams()
{
	CachedDH = DH_new();
	if(CachedDH)
	{
		OpenSSLReseedRandom();
		DH_generate_parameters_ex(CachedDH, 512, DH_GENERATOR_5, 0); 
		//DH_check(CachedDH, &codes); 
	}
}

static int ctx_set_dh(SSL_CTX *ctx, const char *dh_file,
                      const char *dh_special)
{
    DH *dh = NULL;
    FILE *fp = NULL;

    if (dh_special) {
        if (strcmp(dh_special, "NULL") == 0)
            return 1;
        if (strcmp(dh_special, "standard") == 0) {
            if ((dh = get_dh512()) == NULL) {
                fprintf(stderr, "Error, can't parse 'standard'"
                        " DH parameters\n");
                return 0;
            }
            fprintf(stderr, "Info, using 'standard' DH parameters\n");
            goto do_it;
        }
        if (strcmp(dh_special, "generate") != 0)
            /*
             * This shouldn't happen - screening values is handled in main().
             */
            abort();
        fprintf(stderr, "Info, generating DH parameters ... ");
        fflush(stderr);
        if (!(dh = DH_new()) || !DH_generate_parameters_ex(dh, 512,
                                                           DH_GENERATOR_5,
                                                           NULL)) {
            fprintf(stderr, "error!\n");
            if (dh)
                DH_free(dh);
            return 0;
        }
        fprintf(stderr, "complete\n");
        goto do_it;
    }
    /* So, we're loading dh_file */
    if ((fp = fopen(dh_file, "r")) == NULL) {
        fprintf(stderr, "Error, couldn't open '%s' for DH parameters\n",
                dh_file);
        return 0;
    }
    dh = PEM_read_DHparams(fp, NULL, NULL, NULL);
    fclose(fp);
    if (dh == NULL) {
        fprintf(stderr, "Error, could not parse DH parameters from '%s'\n",
                dh_file);
        return 0;
    }
    fprintf(stderr, "Info, using DH parameters from file '%s'\n", dh_file);
 do_it:
    SSL_CTX_set_tmp_dh(ctx, dh);
    DH_free(dh);
    return 1;
}

/* DH: generate shared parameters
*/
static int dh_test()
{
    DH *dh;
    ERR_clear_error();
    dh = FIPS_dh_new();
    if (!dh)
        return 0;
    if (!DH_generate_parameters_ex(dh, 1024, 2, NULL))
        return 0;
    FIPS_dh_free(dh);
    return 1;
}

/*
 *	Generate DH parameters.
 *
 *	Last resort if we can't load precomputed nor hardcoded
 *	parameters.
 */
static DH  *
generate_dh_parameters(int prime_len, int generator)
{
	DH		   *dh;

	if ((dh = DH_new()) == NULL)
		return NULL;

	if (DH_generate_parameters_ex(dh, prime_len, generator, NULL))
		return dh;

	DH_free(dh);
	return NULL;
}

DH *DH_generate_parameters(int prime_len, int generator,
	     void (*callback)(int,int,void *), void *cb_arg)
	{
	BN_GENCB cb;
	DH *ret=NULL;

	if((ret=DH_new()) == NULL)
		return NULL;

	BN_GENCB_set_old(&cb, callback, cb_arg);

	if(DH_generate_parameters_ex(ret, prime_len, generator, &cb))
		return ret;
	DH_free(ret);
	return NULL;
	}

std::string avjackif::async_client_hello(boost::asio::yield_context yield_context)
{
	proto::client_hello client_hello;
	client_hello.set_client("avim");
	client_hello.set_version(0001);

	unsigned char to[512];

	auto dh = DH_new();
	DH_generate_parameters_ex(dh,64,DH_GENERATOR_5,NULL);
	DH_generate_key(dh);

	// 把 g,p, pubkey 傳過去
	client_hello.set_random_g((const void*)to, BN_bn2bin(dh->g, to));
	client_hello.set_random_p((const void*)to, BN_bn2bin(dh->p, to));
	client_hello.set_random_pub_key((const void*)to, BN_bn2bin(dh->pub_key, to));

	auto tobesend = av_router::encode(client_hello);

	boost::asio::async_write(*m_sock, boost::asio::buffer(tobesend), yield_context);

	// 解碼
	std::unique_ptr<proto::server_hello> server_hello(
		(proto::server_hello*)async_read_protobuf_message(*m_sock, yield_context));

	m_remote_addr.reset(new proto::av_address(
		av_address_from_string(server_hello->server_av_address())));

	auto server_pubkey = BN_bin2bn((const unsigned char *) server_hello->random_pub_key().data(),
		server_hello->random_pub_key().length(), NULL);

	m_shared_key.resize(DH_size(dh));
	// 密鑰就算出來啦！
	DH_compute_key(&m_shared_key[0], server_pubkey, dh);
	BN_free(server_pubkey);

    std::printf("key = 0x");
    for (int i=0; i<DH_size(dh); ++i)
	{
        std::printf("%x%x", (m_shared_key[i] >> 4) & 0xf, m_shared_key[i] & 0xf);
    }
    std::printf("\n");
	DH_free(dh);

	return server_hello->random_pub_key();
}

/*
 *	Generate DH parameters.
 *
 *	Last resort if we can't load precomputed nor hardcoded
 *	parameters.
 */
static DH  *
generate_dh_parameters(int prime_len, int generator)
{
#if (OPENSSL_VERSION_NUMBER >= 0x0090800fL)
	DH		   *dh;

	if ((dh = DH_new()) == NULL)
		return NULL;

	if (DH_generate_parameters_ex(dh, prime_len, generator, NULL))
		return dh;

	DH_free(dh);
	return NULL;
#else
	return DH_generate_parameters(prime_len, generator, NULL, NULL);
#endif
}

   bool diffie_hellman::generate_params( int s, uint8_t g )
   {
        ssl_dh dh;
        DH_generate_parameters_ex(dh.obj, s, g, NULL);
#if OPENSSL_VERSION_NUMBER >= 0x10100000L
        ssl_bignum bn_p;
        DH_get0_pqg(dh.obj, (const BIGNUM**)&bn_p.obj, NULL, NULL);
        p.resize( BN_num_bytes( bn_p ) );
        if( p.size() )
            BN_bn2bin( bn_p, (unsigned char*)&p.front()  );
#else
        p.resize( BN_num_bytes( dh->p ) );
        if( p.size() )
            BN_bn2bin( dh->p, (unsigned char*)&p.front()  );
#endif
        this->g = g;
        return fc::validate( dh, valid );
   }

int generate_dhparam(int dh_bits)
{
    DH * dh ;
    char filename[FIELD_SZ+1];
    FILE * out;

    sprintf(filename, "dh%d.pem", dh_bits);
    if ((out=fopen(filename, "wb"))==NULL) {
        fprintf(stderr, "Cannot create %s: aborting\n", filename);
        return -1;
    }
    dh = DH_new();
    printf("Generating DH parameters (%d bits) -- this can take long\n", dh_bits);
    DH_generate_parameters_ex(dh, dh_bits, DH_GENERATOR_2, 0);
    PEM_write_DHparams(out, dh);
    fclose(out);
    printf("done\n");
    return 0;
}