/* * 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 */