/* * Certificate request generation * * 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" #include "mbedtls/platform.h" #if !defined(MBEDTLS_X509_CSR_WRITE_C) || !defined(MBEDTLS_FS_IO) || \ !defined(MBEDTLS_PK_PARSE_C) || !defined(MBEDTLS_SHA256_C) || \ !defined(MBEDTLS_ENTROPY_C) || !defined(MBEDTLS_CTR_DRBG_C) || \ !defined(MBEDTLS_PEM_WRITE_C) int main( void ) { mbedtls_printf( "MBEDTLS_X509_CSR_WRITE_C and/or MBEDTLS_FS_IO and/or " "MBEDTLS_PK_PARSE_C and/or MBEDTLS_SHA256_C and/or " "MBEDTLS_ENTROPY_C and/or MBEDTLS_CTR_DRBG_C " "not defined.\n"); mbedtls_exit( 0 ); } #else #include "mbedtls/x509_csr.h" #include "mbedtls/entropy.h" #include "mbedtls/ctr_drbg.h" #include "mbedtls/error.h" #include #include #include #define DFL_FILENAME "keyfile.key" #define DFL_PASSWORD NULL #define DFL_DEBUG_LEVEL 0 #define DFL_OUTPUT_FILENAME "cert.req" #define DFL_SUBJECT_NAME "CN=Cert,O=mbed TLS,C=UK" #define DFL_KEY_USAGE 0 #define DFL_FORCE_KEY_USAGE 0 #define DFL_NS_CERT_TYPE 0 #define DFL_FORCE_NS_CERT_TYPE 0 #define DFL_MD_ALG MBEDTLS_MD_SHA256 #define USAGE \ "\n usage: cert_req param=<>...\n" \ "\n acceptable parameters:\n" \ " filename=%%s default: keyfile.key\n" \ " password=%%s default: NULL\n" \ " debug_level=%%d default: 0 (disabled)\n" \ " output_file=%%s default: cert.req\n" \ " subject_name=%%s default: CN=Cert,O=mbed TLS,C=UK\n" \ " key_usage=%%s default: (empty)\n" \ " Comma-separated-list of values:\n" \ " digital_signature\n" \ " non_repudiation\n" \ " key_encipherment\n" \ " data_encipherment\n" \ " key_agreement\n" \ " key_cert_sign\n" \ " crl_sign\n" \ " force_key_usage=0/1 default: off\n" \ " Add KeyUsage even if it is empty\n" \ " ns_cert_type=%%s default: (empty)\n" \ " Comma-separated-list of values:\n" \ " ssl_client\n" \ " ssl_server\n" \ " email\n" \ " object_signing\n" \ " ssl_ca\n" \ " email_ca\n" \ " object_signing_ca\n" \ " force_ns_cert_type=0/1 default: off\n" \ " Add NsCertType even if it is empty\n" \ " md=%%s default: SHA256\n" \ " possible values:\n" \ " MD5, RIPEMD160, SHA1,\n" \ " SHA224, SHA256, SHA384, SHA512\n" \ "\n" /* * global options */ struct options { const char *filename; /* filename of the key file */ const char *password; /* password for the key file */ int debug_level; /* level of debugging */ const char *output_file; /* where to store the constructed key file */ const char *subject_name; /* subject name for certificate request */ unsigned char key_usage; /* key usage flags */ int force_key_usage; /* Force adding the KeyUsage extension */ unsigned char ns_cert_type; /* NS cert type */ int force_ns_cert_type; /* Force adding NsCertType extension */ mbedtls_md_type_t md_alg; /* Hash algorithm used for signature. */ } opt; int write_certificate_request( mbedtls_x509write_csr *req, const char *output_file, int (*f_rng)(void *, unsigned char *, size_t), void *p_rng ) { int ret; FILE *f; unsigned char output_buf[4096]; size_t len = 0; memset( output_buf, 0, 4096 ); if( ( ret = mbedtls_x509write_csr_pem( req, output_buf, 4096, f_rng, p_rng ) ) < 0 ) return( ret ); len = strlen( (char *) output_buf ); if( ( f = fopen( output_file, "w" ) ) == NULL ) return( -1 ); if( fwrite( output_buf, 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, *r; mbedtls_x509write_csr req; mbedtls_entropy_context entropy; mbedtls_ctr_drbg_context ctr_drbg; const char *pers = "csr example app"; /* * Set to sane values */ mbedtls_x509write_csr_init( &req ); mbedtls_pk_init( &key ); mbedtls_ctr_drbg_init( &ctr_drbg ); memset( buf, 0, sizeof( buf ) ); if( argc == 0 ) { usage: mbedtls_printf( USAGE ); goto exit; } opt.filename = DFL_FILENAME; opt.password = DFL_PASSWORD; opt.debug_level = DFL_DEBUG_LEVEL; opt.output_file = DFL_OUTPUT_FILENAME; opt.subject_name = DFL_SUBJECT_NAME; opt.key_usage = DFL_KEY_USAGE; opt.force_key_usage = DFL_FORCE_KEY_USAGE; opt.ns_cert_type = DFL_NS_CERT_TYPE; opt.force_ns_cert_type = DFL_FORCE_NS_CERT_TYPE; opt.md_alg = DFL_MD_ALG; for( i = 1; i < argc; i++ ) { p = argv[i]; if( ( q = strchr( p, '=' ) ) == NULL ) goto usage; *q++ = '\0'; if( strcmp( p, "filename" ) == 0 ) opt.filename = q; else if( strcmp( p, "password" ) == 0 ) opt.password = q; else if( strcmp( p, "output_file" ) == 0 ) opt.output_file = q; else if( strcmp( p, "debug_level" ) == 0 ) { opt.debug_level = atoi( q ); if( opt.debug_level < 0 || opt.debug_level > 65535 ) goto usage; } else if( strcmp( p, "subject_name" ) == 0 ) { opt.subject_name = q; } else if( strcmp( p, "md" ) == 0 ) { const mbedtls_md_info_t *md_info = mbedtls_md_info_from_string( q ); if( md_info == NULL ) { mbedtls_printf( "Invalid argument for option %s\n", p ); goto usage; } opt.md_alg = mbedtls_md_get_type( md_info ); } else if( strcmp( p, "key_usage" ) == 0 ) { while( q != NULL ) { if( ( r = strchr( q, ',' ) ) != NULL ) *r++ = '\0'; if( strcmp( q, "digital_signature" ) == 0 ) opt.key_usage |= MBEDTLS_X509_KU_DIGITAL_SIGNATURE; else if( strcmp( q, "non_repudiation" ) == 0 ) opt.key_usage |= MBEDTLS_X509_KU_NON_REPUDIATION; else if( strcmp( q, "key_encipherment" ) == 0 ) opt.key_usage |= MBEDTLS_X509_KU_KEY_ENCIPHERMENT; else if( strcmp( q, "data_encipherment" ) == 0 ) opt.key_usage |= MBEDTLS_X509_KU_DATA_ENCIPHERMENT; else if( strcmp( q, "key_agreement" ) == 0 ) opt.key_usage |= MBEDTLS_X509_KU_KEY_AGREEMENT; else if( strcmp( q, "key_cert_sign" ) == 0 ) opt.key_usage |= MBEDTLS_X509_KU_KEY_CERT_SIGN; else if( strcmp( q, "crl_sign" ) == 0 ) opt.key_usage |= MBEDTLS_X509_KU_CRL_SIGN; else goto usage; q = r; } } else if( strcmp( p, "force_key_usage" ) == 0 ) { switch( atoi( q ) ) { case 0: opt.force_key_usage = 0; break; case 1: opt.force_key_usage = 1; break; default: goto usage; } } else if( strcmp( p, "ns_cert_type" ) == 0 ) { while( q != NULL ) { if( ( r = strchr( q, ',' ) ) != NULL ) *r++ = '\0'; if( strcmp( q, "ssl_client" ) == 0 ) opt.ns_cert_type |= MBEDTLS_X509_NS_CERT_TYPE_SSL_CLIENT; else if( strcmp( q, "ssl_server" ) == 0 ) opt.ns_cert_type |= MBEDTLS_X509_NS_CERT_TYPE_SSL_SERVER; else if( strcmp( q, "email" ) == 0 ) opt.ns_cert_type |= MBEDTLS_X509_NS_CERT_TYPE_EMAIL; else if( strcmp( q, "object_signing" ) == 0 ) opt.ns_cert_type |= MBEDTLS_X509_NS_CERT_TYPE_OBJECT_SIGNING; else if( strcmp( q, "ssl_ca" ) == 0 ) opt.ns_cert_type |= MBEDTLS_X509_NS_CERT_TYPE_SSL_CA; else if( strcmp( q, "email_ca" ) == 0 ) opt.ns_cert_type |= MBEDTLS_X509_NS_CERT_TYPE_EMAIL_CA; else if( strcmp( q, "object_signing_ca" ) == 0 ) opt.ns_cert_type |= MBEDTLS_X509_NS_CERT_TYPE_OBJECT_SIGNING_CA; else goto usage; q = r; } } else if( strcmp( p, "force_ns_cert_type" ) == 0 ) { switch( atoi( q ) ) { case 0: opt.force_ns_cert_type = 0; break; case 1: opt.force_ns_cert_type = 1; break; default: goto usage; } } else goto usage; } mbedtls_x509write_csr_set_md_alg( &req, opt.md_alg ); if( opt.key_usage || opt.force_key_usage == 1 ) mbedtls_x509write_csr_set_key_usage( &req, opt.key_usage ); if( opt.ns_cert_type || opt.force_ns_cert_type == 1 ) mbedtls_x509write_csr_set_ns_cert_type( &req, opt.ns_cert_type ); /* * 0. Seed the PRNG */ mbedtls_printf( " . Seeding the random number generator..." ); fflush( stdout ); mbedtls_entropy_init( &entropy ); 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 %d", ret ); goto exit; } mbedtls_printf( " ok\n" ); /* * 1.0. Check the subject name for validity */ mbedtls_printf( " . Checking subject name..." ); fflush( stdout ); if( ( ret = mbedtls_x509write_csr_set_subject_name( &req, opt.subject_name ) ) != 0 ) { mbedtls_printf( " failed\n ! mbedtls_x509write_csr_set_subject_name returned %d", ret ); goto exit; } mbedtls_printf( " ok\n" ); /* * 1.1. Load the key */ mbedtls_printf( " . Loading the private key ..." ); fflush( stdout ); ret = mbedtls_pk_parse_keyfile( &key, opt.filename, opt.password, mbedtls_ctr_drbg_random, &ctr_drbg ); if( ret != 0 ) { mbedtls_printf( " failed\n ! mbedtls_pk_parse_keyfile returned %d", ret ); goto exit; } mbedtls_x509write_csr_set_key( &req, &key ); mbedtls_printf( " ok\n" ); /* * 1.2. Writing the request */ mbedtls_printf( " . Writing the certificate request ..." ); fflush( stdout ); if( ( ret = write_certificate_request( &req, opt.output_file, mbedtls_ctr_drbg_random, &ctr_drbg ) ) != 0 ) { mbedtls_printf( " failed\n ! write_certificate_request %d", ret ); 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_x509write_csr_free( &req ); mbedtls_pk_free( &key ); mbedtls_ctr_drbg_free( &ctr_drbg ); mbedtls_entropy_free( &entropy ); mbedtls_exit( exit_code ); } #endif /* MBEDTLS_X509_CSR_WRITE_C && MBEDTLS_PK_PARSE_C && MBEDTLS_FS_IO && MBEDTLS_ENTROPY_C && MBEDTLS_CTR_DRBG_C && MBEDTLS_PEM_WRITE_C */