programs/pkey/gen_key.c - third_party/github/ARMmbed/mbedtls - Git at Google

 /*
  *  Key generation application
  *
  *  Copyright The Mbed TLS Contributors
  *  SPDX-License-Identifier: Apache-2.0
  *
  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
  *  not use this file except in compliance with the License.
  *  You may obtain a copy of the License at
  *
  *  http://www.apache.org/licenses/LICENSE-2.0
  *
  *  Unless required by applicable law or agreed to in writing, software
  *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  *  See the License for the specific language governing permissions and
  *  limitations under the License.
  */

 #include "mbedtls/build_info.h"

 #if defined(MBEDTLS_PLATFORM_C)
 #include "mbedtls/platform.h"
 #else
 #include <stdio.h>
 #include <stdlib.h>
 #define mbedtls_printf          printf
 #define mbedtls_exit            exit
 #define MBEDTLS_EXIT_SUCCESS    EXIT_SUCCESS
 #define MBEDTLS_EXIT_FAILURE    EXIT_FAILURE
 #endif /* MBEDTLS_PLATFORM_C */

 #if defined(MBEDTLS_PK_WRITE_C) && defined(MBEDTLS_FS_IO) && \
     defined(MBEDTLS_ENTROPY_C) && defined(MBEDTLS_CTR_DRBG_C)
 #include "mbedtls/error.h"
 #include "mbedtls/pk.h"
 #include "mbedtls/ecdsa.h"
 #include "mbedtls/rsa.h"
 #include "mbedtls/error.h"
 #include "mbedtls/entropy.h"
 #include "mbedtls/ctr_drbg.h"

 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>

 #if !defined(_WIN32)
 #include <unistd.h>

 #define DEV_RANDOM_THRESHOLD        32

 int dev_random_entropy_poll( void *data, unsigned char *output,
                              size_t len, size_t *olen )
 {
     FILE *file;
     size_t ret, left = len;
     unsigned char *p = output;
     ((void) data);

     *olen = 0;

     file = fopen( "/dev/random", "rb" );
     if( file == NULL )
         return( MBEDTLS_ERR_ENTROPY_SOURCE_FAILED );

     while( left > 0 )
     {
         /* /dev/random can return much less than requested. If so, try again */
         ret = fread( p, 1, left, file );
         if( ret == 0 && ferror( file ) )
         {
             fclose( file );
             return( MBEDTLS_ERR_ENTROPY_SOURCE_FAILED );
         }

         p += ret;
         left -= ret;
         sleep( 1 );
     }
     fclose( file );
     *olen = len;

     return( 0 );
 }
 #endif /* !_WIN32 */
 #endif

 #if defined(MBEDTLS_ECP_C)
 #define DFL_EC_CURVE            mbedtls_ecp_curve_list()->grp_id
 #else
 #define DFL_EC_CURVE            0
 #endif

 #if !defined(_WIN32) && defined(MBEDTLS_FS_IO)
 #define USAGE_DEV_RANDOM \
     "    use_dev_random=0|1    default: 0\n"
 #else
 #define USAGE_DEV_RANDOM ""
 #endif /* !_WIN32 && MBEDTLS_FS_IO */

 #define FORMAT_PEM              0
 #define FORMAT_DER              1

 #define DFL_TYPE                MBEDTLS_PK_RSA
 #define DFL_RSA_KEYSIZE         4096
 #define DFL_FILENAME            "keyfile.key"
 #define DFL_FORMAT              FORMAT_PEM
 #define DFL_USE_DEV_RANDOM      0

 #define USAGE \
     "\n usage: gen_key param=<>...\n"                   \
     "\n acceptable parameters:\n"                       \
     "    type=rsa|ec           default: rsa\n"          \
     "    rsa_keysize=%%d        default: 4096\n"        \
     "    ec_curve=%%s           see below\n"            \
     "    filename=%%s           default: keyfile.key\n" \
     "    format=pem|der        default: pem\n"          \
     USAGE_DEV_RANDOM                                    \
     "\n"

 #if !defined(MBEDTLS_PK_WRITE_C) || !defined(MBEDTLS_PEM_WRITE_C) || \
     !defined(MBEDTLS_FS_IO) || !defined(MBEDTLS_ENTROPY_C) || \
     !defined(MBEDTLS_CTR_DRBG_C)
 int main( void )
 {
     mbedtls_printf( "MBEDTLS_PK_WRITE_C and/or MBEDTLS_FS_IO and/or "
             "MBEDTLS_ENTROPY_C and/or MBEDTLS_CTR_DRBG_C and/or "
             "MBEDTLS_PEM_WRITE_C"
             "not defined.\n" );
     mbedtls_exit( 0 );
 }
 #else


 /*
  * global options
  */
 struct options
 {
     int type;                   /* the type of key to generate          */
     int rsa_keysize;            /* length of key in bits                */
     int ec_curve;               /* curve identifier for EC keys         */
     const char *filename;       /* filename of the key file             */
     int format;                 /* the output format to use             */
     int use_dev_random;         /* use /dev/random as entropy source    */
 } opt;

 static int write_private_key( mbedtls_pk_context *key, const char *output_file )
 {
     int ret;
     FILE *f;
     unsigned char output_buf[16000];
     unsigned char *c = output_buf;
     size_t len = 0;

     memset(output_buf, 0, 16000);
     if( opt.format == FORMAT_PEM )
     {
         if( ( ret = mbedtls_pk_write_key_pem( key, output_buf, 16000 ) ) != 0 )
             return( ret );

         len = strlen( (char *) output_buf );
     }
     else
     {
         if( ( ret = mbedtls_pk_write_key_der( key, output_buf, 16000 ) ) < 0 )
             return( ret );

         len = ret;
         c = output_buf + sizeof(output_buf) - len;
     }

     if( ( f = fopen( output_file, "wb" ) ) == NULL )
         return( -1 );

     if( fwrite( c, 1, len, f ) != len )
     {
         fclose( f );
         return( -1 );
     }

     fclose( f );

     return( 0 );
 }

 int main( int argc, char *argv[] )
 {
     int ret = 1;
     int exit_code = MBEDTLS_EXIT_FAILURE;
     mbedtls_pk_context key;
     char buf[1024];
     int i;
     char *p, *q;
     mbedtls_mpi N, P, Q, D, E, DP, DQ, QP;
     mbedtls_entropy_context entropy;
     mbedtls_ctr_drbg_context ctr_drbg;
     const char *pers = "gen_key";
 #if defined(MBEDTLS_ECP_C)
     const mbedtls_ecp_curve_info *curve_info;
 #endif

     /*
      * Set to sane values
      */

     mbedtls_mpi_init( &N ); mbedtls_mpi_init( &P ); mbedtls_mpi_init( &Q );
     mbedtls_mpi_init( &D ); mbedtls_mpi_init( &E ); mbedtls_mpi_init( &DP );
     mbedtls_mpi_init( &DQ ); mbedtls_mpi_init( &QP );

     mbedtls_pk_init( &key );
     mbedtls_ctr_drbg_init( &ctr_drbg );
     memset( buf, 0, sizeof( buf ) );

     if( argc == 0 )
     {
     usage:
         mbedtls_printf( USAGE );
 #if defined(MBEDTLS_ECP_C)
         mbedtls_printf( " available ec_curve values:\n" );
         curve_info = mbedtls_ecp_curve_list();
         mbedtls_printf( "    %s (default)\n", curve_info->name );
         while( ( ++curve_info )->name != NULL )
             mbedtls_printf( "    %s\n", curve_info->name );
 #endif /* MBEDTLS_ECP_C */
         goto exit;
     }

     opt.type                = DFL_TYPE;
     opt.rsa_keysize         = DFL_RSA_KEYSIZE;
     opt.ec_curve            = DFL_EC_CURVE;
     opt.filename            = DFL_FILENAME;
     opt.format              = DFL_FORMAT;
     opt.use_dev_random      = DFL_USE_DEV_RANDOM;

     for( i = 1; i < argc; i++ )
     {
         p = argv[i];
         if( ( q = strchr( p, '=' ) ) == NULL )
             goto usage;
         *q++ = '\0';

         if( strcmp( p, "type" ) == 0 )
         {
             if( strcmp( q, "rsa" ) == 0 )
                 opt.type = MBEDTLS_PK_RSA;
             else if( strcmp( q, "ec" ) == 0 )
                 opt.type = MBEDTLS_PK_ECKEY;
             else
                 goto usage;
         }
         else if( strcmp( p, "format" ) == 0 )
         {
             if( strcmp( q, "pem" ) == 0 )
                 opt.format = FORMAT_PEM;
             else if( strcmp( q, "der" ) == 0 )
                 opt.format = FORMAT_DER;
             else
                 goto usage;
         }
         else if( strcmp( p, "rsa_keysize" ) == 0 )
         {
             opt.rsa_keysize = atoi( q );
             if( opt.rsa_keysize < 1024 ||
                 opt.rsa_keysize > MBEDTLS_MPI_MAX_BITS )
                 goto usage;
         }
 #if defined(MBEDTLS_ECP_C)
         else if( strcmp( p, "ec_curve" ) == 0 )
         {
             if( ( curve_info = mbedtls_ecp_curve_info_from_name( q ) ) == NULL )
                 goto usage;
             opt.ec_curve = curve_info->grp_id;
         }
 #endif
         else if( strcmp( p, "filename" ) == 0 )
             opt.filename = q;
         else if( strcmp( p, "use_dev_random" ) == 0 )
         {
             opt.use_dev_random = atoi( q );
             if( opt.use_dev_random < 0 || opt.use_dev_random > 1 )
                 goto usage;
         }
         else
             goto usage;
     }

     mbedtls_printf( "\n  . Seeding the random number generator..." );
     fflush( stdout );

     mbedtls_entropy_init( &entropy );
 #if !defined(_WIN32) && defined(MBEDTLS_FS_IO)
     if( opt.use_dev_random )
     {
         if( ( ret = mbedtls_entropy_add_source( &entropy, dev_random_entropy_poll,
                                         NULL, DEV_RANDOM_THRESHOLD,
                                         MBEDTLS_ENTROPY_SOURCE_STRONG ) ) != 0 )
         {
             mbedtls_printf( " failed\n  ! mbedtls_entropy_add_source returned -0x%04x\n", (unsigned int) -ret );
             goto exit;
         }

         mbedtls_printf("\n    Using /dev/random, so can take a long time! " );
         fflush( stdout );
     }
 #endif /* !_WIN32 && MBEDTLS_FS_IO */

     if( ( ret = mbedtls_ctr_drbg_seed( &ctr_drbg, mbedtls_entropy_func, &entropy,
                                (const unsigned char *) pers,
                                strlen( pers ) ) ) != 0 )
     {
         mbedtls_printf( " failed\n  ! mbedtls_ctr_drbg_seed returned -0x%04x\n", (unsigned int) -ret );
         goto exit;
     }

     /*
      * 1.1. Generate the key
      */
     mbedtls_printf( "\n  . Generating the private key ..." );
     fflush( stdout );

     if( ( ret = mbedtls_pk_setup( &key,
             mbedtls_pk_info_from_type( (mbedtls_pk_type_t) opt.type ) ) ) != 0 )
     {
         mbedtls_printf( " failed\n  !  mbedtls_pk_setup returned -0x%04x", (unsigned int) -ret );
         goto exit;
     }

 #if defined(MBEDTLS_RSA_C) && defined(MBEDTLS_GENPRIME)
     if( opt.type == MBEDTLS_PK_RSA )
     {
         ret = mbedtls_rsa_gen_key( mbedtls_pk_rsa( key ), mbedtls_ctr_drbg_random, &ctr_drbg,
                                    opt.rsa_keysize, 65537 );
         if( ret != 0 )
         {
             mbedtls_printf( " failed\n  !  mbedtls_rsa_gen_key returned -0x%04x", (unsigned int) -ret );
             goto exit;
         }
     }
     else
 #endif /* MBEDTLS_RSA_C */
 #if defined(MBEDTLS_ECP_C)
     if( opt.type == MBEDTLS_PK_ECKEY )
     {
         ret = mbedtls_ecp_gen_key( (mbedtls_ecp_group_id) opt.ec_curve,
                                    mbedtls_pk_ec( key ),
                                    mbedtls_ctr_drbg_random, &ctr_drbg );
         if( ret != 0 )
         {
             mbedtls_printf( " failed\n  !  mbedtls_ecp_gen_key returned -0x%04x", (unsigned int) -ret );
             goto exit;
         }
     }
     else
 #endif /* MBEDTLS_ECP_C */
     {
         mbedtls_printf( " failed\n  !  key type not supported\n" );
         goto exit;
     }

     /*
      * 1.2 Print the key
      */
     mbedtls_printf( " ok\n  . Key information:\n" );

 #if defined(MBEDTLS_RSA_C)
     if( mbedtls_pk_get_type( &key ) == MBEDTLS_PK_RSA )
     {
         mbedtls_rsa_context *rsa = mbedtls_pk_rsa( key );

         if( ( ret = mbedtls_rsa_export    ( rsa, &N, &P, &Q, &D, &E ) ) != 0 ||
             ( ret = mbedtls_rsa_export_crt( rsa, &DP, &DQ, &QP ) )      != 0 )
         {
             mbedtls_printf( " failed\n  ! could not export RSA parameters\n\n" );
             goto exit;
         }

         mbedtls_mpi_write_file( "N:  ",  &N,  16, NULL );
         mbedtls_mpi_write_file( "E:  ",  &E,  16, NULL );
         mbedtls_mpi_write_file( "D:  ",  &D,  16, NULL );
         mbedtls_mpi_write_file( "P:  ",  &P,  16, NULL );
         mbedtls_mpi_write_file( "Q:  ",  &Q,  16, NULL );
         mbedtls_mpi_write_file( "DP: ",  &DP, 16, NULL );
         mbedtls_mpi_write_file( "DQ:  ", &DQ, 16, NULL );
         mbedtls_mpi_write_file( "QP:  ", &QP, 16, NULL );
     }
     else
 #endif
 #if defined(MBEDTLS_ECP_C)
     if( mbedtls_pk_get_type( &key ) == MBEDTLS_PK_ECKEY )
     {
         mbedtls_ecp_keypair *ecp = mbedtls_pk_ec( key );
         mbedtls_printf( "curve: %s\n",
                 mbedtls_ecp_curve_info_from_grp_id( ecp->MBEDTLS_PRIVATE(grp).id )->name );
         mbedtls_mpi_write_file( "X_Q:   ", &ecp->MBEDTLS_PRIVATE(Q).MBEDTLS_PRIVATE(X), 16, NULL );
         mbedtls_mpi_write_file( "Y_Q:   ", &ecp->MBEDTLS_PRIVATE(Q).MBEDTLS_PRIVATE(Y), 16, NULL );
         mbedtls_mpi_write_file( "D:     ", &ecp->MBEDTLS_PRIVATE(d)  , 16, NULL );
     }
     else
 #endif
         mbedtls_printf("  ! key type not supported\n");

     /*
      * 1.3 Export key
      */
     mbedtls_printf( "  . Writing key to file..." );

     if( ( ret = write_private_key( &key, opt.filename ) ) != 0 )
     {
         mbedtls_printf( " failed\n" );
         goto exit;
     }

     mbedtls_printf( " ok\n" );

     exit_code = MBEDTLS_EXIT_SUCCESS;

 exit:

     if( exit_code != MBEDTLS_EXIT_SUCCESS )
     {
 #ifdef MBEDTLS_ERROR_C
         mbedtls_strerror( ret, buf, sizeof( buf ) );
         mbedtls_printf( " - %s\n", buf );
 #else
         mbedtls_printf("\n");
 #endif
     }

     mbedtls_mpi_free( &N ); mbedtls_mpi_free( &P ); mbedtls_mpi_free( &Q );
     mbedtls_mpi_free( &D ); mbedtls_mpi_free( &E ); mbedtls_mpi_free( &DP );
     mbedtls_mpi_free( &DQ ); mbedtls_mpi_free( &QP );

     mbedtls_pk_free( &key );
     mbedtls_ctr_drbg_free( &ctr_drbg );
     mbedtls_entropy_free( &entropy );

 #if defined(_WIN32)
     mbedtls_printf( "  + Press Enter to exit this program.\n" );
     fflush( stdout ); getchar();
 #endif

     mbedtls_exit( exit_code );
 }
 #endif /* MBEDTLS_PK_WRITE_C && MBEDTLS_PEM_WRITE_C && MBEDTLS_FS_IO &&
         * MBEDTLS_ENTROPY_C && MBEDTLS_CTR_DRBG_C */
	/*
	* Key generation application
	*
	* Copyright The Mbed TLS Contributors
	* SPDX-License-Identifier: Apache-2.0
	*
	* Licensed under the Apache License, Version 2.0 (the "License"); you may
	* not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
	* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	#include "mbedtls/build_info.h"

	#if defined(MBEDTLS_PLATFORM_C)
	#include "mbedtls/platform.h"
	#else
	#include <stdio.h>
	#include <stdlib.h>
	#define mbedtls_printf printf
	#define mbedtls_exit exit
	#define MBEDTLS_EXIT_SUCCESS EXIT_SUCCESS
	#define MBEDTLS_EXIT_FAILURE EXIT_FAILURE
	#endif /* MBEDTLS_PLATFORM_C */

	#if defined(MBEDTLS_PK_WRITE_C) && defined(MBEDTLS_FS_IO) && \
	defined(MBEDTLS_ENTROPY_C) && defined(MBEDTLS_CTR_DRBG_C)
	#include "mbedtls/error.h"
	#include "mbedtls/pk.h"
	#include "mbedtls/ecdsa.h"
	#include "mbedtls/rsa.h"
	#include "mbedtls/error.h"
	#include "mbedtls/entropy.h"
	#include "mbedtls/ctr_drbg.h"

	#include <stdio.h>
	#include <stdlib.h>
	#include <string.h>

	#if !defined(_WIN32)
	#include <unistd.h>

	#define DEV_RANDOM_THRESHOLD 32

	int dev_random_entropy_poll( void data, unsigned char output,
	size_t len, size_t *olen )
	{
	FILE *file;
	size_t ret, left = len;
	unsigned char *p = output;
	((void) data);

	*olen = 0;

	file = fopen( "/dev/random", "rb" );
	if( file == NULL )
	return( MBEDTLS_ERR_ENTROPY_SOURCE_FAILED );

	while( left > 0 )
	{
	/* /dev/random can return much less than requested. If so, try again */
	ret = fread( p, 1, left, file );
	if( ret == 0 && ferror( file ) )
	{
	fclose( file );
	return( MBEDTLS_ERR_ENTROPY_SOURCE_FAILED );
	}

	p += ret;
	left -= ret;
	sleep( 1 );
	}
	fclose( file );
	*olen = len;

	return( 0 );
	}
	#endif /* !_WIN32 */
	#endif

	#if defined(MBEDTLS_ECP_C)
	#define DFL_EC_CURVE mbedtls_ecp_curve_list()->grp_id
	#else
	#define DFL_EC_CURVE 0
	#endif

	#if !defined(_WIN32) && defined(MBEDTLS_FS_IO)
	#define USAGE_DEV_RANDOM \
	" use_dev_random=0\|1 default: 0\n"
	#else
	#define USAGE_DEV_RANDOM ""
	#endif /* !_WIN32 && MBEDTLS_FS_IO */

	#define FORMAT_PEM 0
	#define FORMAT_DER 1

	#define DFL_TYPE MBEDTLS_PK_RSA
	#define DFL_RSA_KEYSIZE 4096
	#define DFL_FILENAME "keyfile.key"
	#define DFL_FORMAT FORMAT_PEM
	#define DFL_USE_DEV_RANDOM 0

	#define USAGE \
	"\n usage: gen_key param=<>...\n" \
	"\n acceptable parameters:\n" \
	" type=rsa\|ec default: rsa\n" \
	" rsa_keysize=%%d default: 4096\n" \
	" ec_curve=%%s see below\n" \
	" filename=%%s default: keyfile.key\n" \
	" format=pem\|der default: pem\n" \
	USAGE_DEV_RANDOM \
	"\n"

	#if !defined(MBEDTLS_PK_WRITE_C) \|\| !defined(MBEDTLS_PEM_WRITE_C) \|\| \
	!defined(MBEDTLS_FS_IO) \|\| !defined(MBEDTLS_ENTROPY_C) \|\| \
	!defined(MBEDTLS_CTR_DRBG_C)
	int main( void )
	{
	mbedtls_printf( "MBEDTLS_PK_WRITE_C and/or MBEDTLS_FS_IO and/or "
	"MBEDTLS_ENTROPY_C and/or MBEDTLS_CTR_DRBG_C and/or "
	"MBEDTLS_PEM_WRITE_C"
	"not defined.\n" );
	mbedtls_exit( 0 );
	}
	#else


	/*
	* global options
	*/
	struct options
	{
	int type; /* the type of key to generate */
	int rsa_keysize; /* length of key in bits */
	int ec_curve; /* curve identifier for EC keys */
	const char filename; / filename of the key file */
	int format; /* the output format to use */
	int use_dev_random; /* use /dev/random as entropy source */
	} opt;

	static int write_private_key( mbedtls_pk_context key, const char output_file )
	{
	int ret;
	FILE *f;
	unsigned char output_buf[16000];
	unsigned char *c = output_buf;
	size_t len = 0;

	memset(output_buf, 0, 16000);
	if( opt.format == FORMAT_PEM )
	{
	if( ( ret = mbedtls_pk_write_key_pem( key, output_buf, 16000 ) ) != 0 )
	return( ret );

	len = strlen( (char *) output_buf );
	}
	else
	{
	if( ( ret = mbedtls_pk_write_key_der( key, output_buf, 16000 ) ) < 0 )
	return( ret );

	len = ret;
	c = output_buf + sizeof(output_buf) - len;
	}

	if( ( f = fopen( output_file, "wb" ) ) == NULL )
	return( -1 );

	if( fwrite( c, 1, len, f ) != len )
	{
	fclose( f );
	return( -1 );
	}

	fclose( f );

	return( 0 );
	}

	int main( int argc, char *argv[] )
	{
	int ret = 1;
	int exit_code = MBEDTLS_EXIT_FAILURE;
	mbedtls_pk_context key;
	char buf[1024];
	int i;
	char p, q;
	mbedtls_mpi N, P, Q, D, E, DP, DQ, QP;
	mbedtls_entropy_context entropy;
	mbedtls_ctr_drbg_context ctr_drbg;
	const char *pers = "gen_key";
	#if defined(MBEDTLS_ECP_C)
	const mbedtls_ecp_curve_info *curve_info;
	#endif

	/*
	* Set to sane values
	*/

	mbedtls_mpi_init( &N ); mbedtls_mpi_init( &P ); mbedtls_mpi_init( &Q );
	mbedtls_mpi_init( &D ); mbedtls_mpi_init( &E ); mbedtls_mpi_init( &DP );
	mbedtls_mpi_init( &DQ ); mbedtls_mpi_init( &QP );

	mbedtls_pk_init( &key );
	mbedtls_ctr_drbg_init( &ctr_drbg );
	memset( buf, 0, sizeof( buf ) );

	if( argc == 0 )
	{
	usage:
	mbedtls_printf( USAGE );
	#if defined(MBEDTLS_ECP_C)
	mbedtls_printf( " available ec_curve values:\n" );
	curve_info = mbedtls_ecp_curve_list();
	mbedtls_printf( " %s (default)\n", curve_info->name );
	while( ( ++curve_info )->name != NULL )
	mbedtls_printf( " %s\n", curve_info->name );
	#endif /* MBEDTLS_ECP_C */
	goto exit;
	}

	opt.type = DFL_TYPE;
	opt.rsa_keysize = DFL_RSA_KEYSIZE;
	opt.ec_curve = DFL_EC_CURVE;
	opt.filename = DFL_FILENAME;
	opt.format = DFL_FORMAT;
	opt.use_dev_random = DFL_USE_DEV_RANDOM;

	for( i = 1; i < argc; i++ )
	{
	p = argv[i];
	if( ( q = strchr( p, '=' ) ) == NULL )
	goto usage;
	*q++ = '\0';

	if( strcmp( p, "type" ) == 0 )
	{
	if( strcmp( q, "rsa" ) == 0 )
	opt.type = MBEDTLS_PK_RSA;
	else if( strcmp( q, "ec" ) == 0 )
	opt.type = MBEDTLS_PK_ECKEY;
	else
	goto usage;
	}
	else if( strcmp( p, "format" ) == 0 )
	{
	if( strcmp( q, "pem" ) == 0 )
	opt.format = FORMAT_PEM;
	else if( strcmp( q, "der" ) == 0 )
	opt.format = FORMAT_DER;
	else
	goto usage;
	}
	else if( strcmp( p, "rsa_keysize" ) == 0 )
	{
	opt.rsa_keysize = atoi( q );
	if( opt.rsa_keysize < 1024 \|\|
	opt.rsa_keysize > MBEDTLS_MPI_MAX_BITS )
	goto usage;
	}
	#if defined(MBEDTLS_ECP_C)
	else if( strcmp( p, "ec_curve" ) == 0 )
	{
	if( ( curve_info = mbedtls_ecp_curve_info_from_name( q ) ) == NULL )
	goto usage;
	opt.ec_curve = curve_info->grp_id;
	}
	#endif
	else if( strcmp( p, "filename" ) == 0 )
	opt.filename = q;
	else if( strcmp( p, "use_dev_random" ) == 0 )
	{
	opt.use_dev_random = atoi( q );
	if( opt.use_dev_random < 0 \|\| opt.use_dev_random > 1 )
	goto usage;
	}
	else
	goto usage;
	}

	mbedtls_printf( "\n . Seeding the random number generator..." );
	fflush( stdout );

	mbedtls_entropy_init( &entropy );
	#if !defined(_WIN32) && defined(MBEDTLS_FS_IO)
	if( opt.use_dev_random )
	{
	if( ( ret = mbedtls_entropy_add_source( &entropy, dev_random_entropy_poll,
	NULL, DEV_RANDOM_THRESHOLD,
	MBEDTLS_ENTROPY_SOURCE_STRONG ) ) != 0 )
	{
	mbedtls_printf( " failed\n ! mbedtls_entropy_add_source returned -0x%04x\n", (unsigned int) -ret );
	goto exit;
	}

	mbedtls_printf("\n Using /dev/random, so can take a long time! " );
	fflush( stdout );
	}
	#endif /* !_WIN32 && MBEDTLS_FS_IO */

	if( ( ret = mbedtls_ctr_drbg_seed( &ctr_drbg, mbedtls_entropy_func, &entropy,
	(const unsigned char *) pers,
	strlen( pers ) ) ) != 0 )
	{
	mbedtls_printf( " failed\n ! mbedtls_ctr_drbg_seed returned -0x%04x\n", (unsigned int) -ret );
	goto exit;
	}

	/*
	* 1.1. Generate the key
	*/
	mbedtls_printf( "\n . Generating the private key ..." );
	fflush( stdout );

	if( ( ret = mbedtls_pk_setup( &key,
	mbedtls_pk_info_from_type( (mbedtls_pk_type_t) opt.type ) ) ) != 0 )
	{
	mbedtls_printf( " failed\n ! mbedtls_pk_setup returned -0x%04x", (unsigned int) -ret );
	goto exit;
	}

	#if defined(MBEDTLS_RSA_C) && defined(MBEDTLS_GENPRIME)
	if( opt.type == MBEDTLS_PK_RSA )
	{
	ret = mbedtls_rsa_gen_key( mbedtls_pk_rsa( key ), mbedtls_ctr_drbg_random, &ctr_drbg,
	opt.rsa_keysize, 65537 );
	if( ret != 0 )
	{
	mbedtls_printf( " failed\n ! mbedtls_rsa_gen_key returned -0x%04x", (unsigned int) -ret );
	goto exit;
	}
	}
	else
	#endif /* MBEDTLS_RSA_C */
	#if defined(MBEDTLS_ECP_C)
	if( opt.type == MBEDTLS_PK_ECKEY )
	{
	ret = mbedtls_ecp_gen_key( (mbedtls_ecp_group_id) opt.ec_curve,
	mbedtls_pk_ec( key ),
	mbedtls_ctr_drbg_random, &ctr_drbg );
	if( ret != 0 )
	{
	mbedtls_printf( " failed\n ! mbedtls_ecp_gen_key returned -0x%04x", (unsigned int) -ret );
	goto exit;
	}
	}
	else
	#endif /* MBEDTLS_ECP_C */
	{
	mbedtls_printf( " failed\n ! key type not supported\n" );
	goto exit;
	}

	/*
	* 1.2 Print the key
	*/
	mbedtls_printf( " ok\n . Key information:\n" );

	#if defined(MBEDTLS_RSA_C)
	if( mbedtls_pk_get_type( &key ) == MBEDTLS_PK_RSA )
	{
	mbedtls_rsa_context *rsa = mbedtls_pk_rsa( key );

	if( ( ret = mbedtls_rsa_export ( rsa, &N, &P, &Q, &D, &E ) ) != 0 \|\|
	( ret = mbedtls_rsa_export_crt( rsa, &DP, &DQ, &QP ) ) != 0 )
	{
	mbedtls_printf( " failed\n ! could not export RSA parameters\n\n" );
	goto exit;
	}

	mbedtls_mpi_write_file( "N: ", &N, 16, NULL );
	mbedtls_mpi_write_file( "E: ", &E, 16, NULL );
	mbedtls_mpi_write_file( "D: ", &D, 16, NULL );
	mbedtls_mpi_write_file( "P: ", &P, 16, NULL );
	mbedtls_mpi_write_file( "Q: ", &Q, 16, NULL );
	mbedtls_mpi_write_file( "DP: ", &DP, 16, NULL );
	mbedtls_mpi_write_file( "DQ: ", &DQ, 16, NULL );
	mbedtls_mpi_write_file( "QP: ", &QP, 16, NULL );
	}
	else
	#endif
	#if defined(MBEDTLS_ECP_C)
	if( mbedtls_pk_get_type( &key ) == MBEDTLS_PK_ECKEY )
	{
	mbedtls_ecp_keypair *ecp = mbedtls_pk_ec( key );
	mbedtls_printf( "curve: %s\n",
	mbedtls_ecp_curve_info_from_grp_id( ecp->MBEDTLS_PRIVATE(grp).id )->name );
	mbedtls_mpi_write_file( "X_Q: ", &ecp->MBEDTLS_PRIVATE(Q).MBEDTLS_PRIVATE(X), 16, NULL );
	mbedtls_mpi_write_file( "Y_Q: ", &ecp->MBEDTLS_PRIVATE(Q).MBEDTLS_PRIVATE(Y), 16, NULL );
	mbedtls_mpi_write_file( "D: ", &ecp->MBEDTLS_PRIVATE(d) , 16, NULL );
	}
	else
	#endif
	mbedtls_printf(" ! key type not supported\n");

	/*
	* 1.3 Export key
	*/
	mbedtls_printf( " . Writing key to file..." );

	if( ( ret = write_private_key( &key, opt.filename ) ) != 0 )
	{
	mbedtls_printf( " failed\n" );
	goto exit;
	}

	mbedtls_printf( " ok\n" );

	exit_code = MBEDTLS_EXIT_SUCCESS;

	exit:

	if( exit_code != MBEDTLS_EXIT_SUCCESS )
	{
	#ifdef MBEDTLS_ERROR_C
	mbedtls_strerror( ret, buf, sizeof( buf ) );
	mbedtls_printf( " - %s\n", buf );
	#else
	mbedtls_printf("\n");
	#endif
	}

	mbedtls_mpi_free( &N ); mbedtls_mpi_free( &P ); mbedtls_mpi_free( &Q );
	mbedtls_mpi_free( &D ); mbedtls_mpi_free( &E ); mbedtls_mpi_free( &DP );
	mbedtls_mpi_free( &DQ ); mbedtls_mpi_free( &QP );

	mbedtls_pk_free( &key );
	mbedtls_ctr_drbg_free( &ctr_drbg );
	mbedtls_entropy_free( &entropy );

	#if defined(_WIN32)
	mbedtls_printf( " + Press Enter to exit this program.\n" );
	fflush( stdout ); getchar();
	#endif

	mbedtls_exit( exit_code );
	}
	#endif /* MBEDTLS_PK_WRITE_C && MBEDTLS_PEM_WRITE_C && MBEDTLS_FS_IO &&
	* MBEDTLS_ENTROPY_C && MBEDTLS_CTR_DRBG_C */