programs/x509/cert_req.c - mirror/mbed-tls - TrustedFirmware Git Browser

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

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

	#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 */