mbedtls/programs/pkey/gen_key.c
Gilles Peskine a73b577744 Make the fields of mbedtls_ecp_curve_info public
The whole point of this structure is to provide information, both for the
library's own sake and to applications.

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2021-08-31 22:52:41 +02:00

447 lines
13 KiB
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 */