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			638 lines
		
	
	
		
			23 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			638 lines
		
	
	
		
			23 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  *  X.509 certificate writing
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|  *
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|  *  Copyright The Mbed TLS Contributors
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|  *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
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|  */
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| /*
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|  * References:
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|  * - certificates: RFC 5280, updated by RFC 6818
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|  * - CSRs: PKCS#10 v1.7 aka RFC 2986
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|  * - attributes: PKCS#9 v2.0 aka RFC 2985
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|  */
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| 
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| #include "x509_internal.h"
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| 
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| #if defined(MBEDTLS_X509_CRT_WRITE_C)
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| 
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| #include "mbedtls/x509_crt.h"
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| #include "mbedtls/asn1write.h"
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| #include "mbedtls/error.h"
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| #include "mbedtls/oid.h"
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| #include "x509_oid.h"
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| #include "mbedtls/platform.h"
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| #include "mbedtls/platform_util.h"
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| #include "mbedtls/md.h"
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| 
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| #include <string.h>
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| #include <stdint.h>
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| 
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| #if defined(MBEDTLS_PEM_WRITE_C)
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| #include "mbedtls/pem.h"
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| #endif /* MBEDTLS_PEM_WRITE_C */
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| 
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| #include "psa/crypto.h"
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| #include "psa_util_internal.h"
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| #include "mbedtls/psa_util.h"
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| 
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| void mbedtls_x509write_crt_init(mbedtls_x509write_cert *ctx)
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| {
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|     memset(ctx, 0, sizeof(mbedtls_x509write_cert));
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| 
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|     ctx->version = MBEDTLS_X509_CRT_VERSION_3;
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| }
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| 
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| void mbedtls_x509write_crt_free(mbedtls_x509write_cert *ctx)
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| {
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|     if (ctx == NULL) {
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|         return;
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|     }
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| 
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|     mbedtls_asn1_free_named_data_list(&ctx->subject);
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|     mbedtls_asn1_free_named_data_list(&ctx->issuer);
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|     mbedtls_asn1_free_named_data_list(&ctx->extensions);
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| 
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|     mbedtls_platform_zeroize(ctx, sizeof(mbedtls_x509write_cert));
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| }
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| 
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| void mbedtls_x509write_crt_set_version(mbedtls_x509write_cert *ctx,
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|                                        int version)
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| {
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|     ctx->version = version;
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| }
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| 
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| void mbedtls_x509write_crt_set_md_alg(mbedtls_x509write_cert *ctx,
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|                                       mbedtls_md_type_t md_alg)
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| {
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|     ctx->md_alg = md_alg;
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| }
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| 
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| void mbedtls_x509write_crt_set_subject_key(mbedtls_x509write_cert *ctx,
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|                                            mbedtls_pk_context *key)
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| {
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|     ctx->subject_key = key;
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| }
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| 
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| void mbedtls_x509write_crt_set_issuer_key(mbedtls_x509write_cert *ctx,
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|                                           mbedtls_pk_context *key)
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| {
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|     ctx->issuer_key = key;
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| }
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| 
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| int mbedtls_x509write_crt_set_subject_name(mbedtls_x509write_cert *ctx,
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|                                            const char *subject_name)
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| {
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|     mbedtls_asn1_free_named_data_list(&ctx->subject);
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|     return mbedtls_x509_string_to_names(&ctx->subject, subject_name);
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| }
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| 
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| int mbedtls_x509write_crt_set_issuer_name(mbedtls_x509write_cert *ctx,
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|                                           const char *issuer_name)
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| {
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|     mbedtls_asn1_free_named_data_list(&ctx->issuer);
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|     return mbedtls_x509_string_to_names(&ctx->issuer, issuer_name);
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| }
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| 
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| int mbedtls_x509write_crt_set_serial_raw(mbedtls_x509write_cert *ctx,
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|                                          const unsigned char *serial, size_t serial_len)
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| {
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|     if (serial_len > MBEDTLS_X509_RFC5280_MAX_SERIAL_LEN) {
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|         return MBEDTLS_ERR_X509_BAD_INPUT_DATA;
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|     }
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| 
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|     ctx->serial_len = serial_len;
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|     memcpy(ctx->serial, serial, serial_len);
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| 
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|     return 0;
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| }
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| 
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| int mbedtls_x509write_crt_set_validity(mbedtls_x509write_cert *ctx,
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|                                        const char *not_before,
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|                                        const char *not_after)
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| {
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|     if (strlen(not_before) != MBEDTLS_X509_RFC5280_UTC_TIME_LEN - 1 ||
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|         strlen(not_after)  != MBEDTLS_X509_RFC5280_UTC_TIME_LEN - 1) {
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|         return MBEDTLS_ERR_X509_BAD_INPUT_DATA;
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|     }
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|     strncpy(ctx->not_before, not_before, MBEDTLS_X509_RFC5280_UTC_TIME_LEN);
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|     strncpy(ctx->not_after, not_after, MBEDTLS_X509_RFC5280_UTC_TIME_LEN);
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|     ctx->not_before[MBEDTLS_X509_RFC5280_UTC_TIME_LEN - 1] = 'Z';
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|     ctx->not_after[MBEDTLS_X509_RFC5280_UTC_TIME_LEN - 1] = 'Z';
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| 
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|     return 0;
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| }
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| 
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| int mbedtls_x509write_crt_set_subject_alternative_name(mbedtls_x509write_cert *ctx,
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|                                                        const mbedtls_x509_san_list *san_list)
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| {
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|     return mbedtls_x509_write_set_san_common(&ctx->extensions, san_list);
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| }
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| 
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| 
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| int mbedtls_x509write_crt_set_extension(mbedtls_x509write_cert *ctx,
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|                                         const char *oid, size_t oid_len,
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|                                         int critical,
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|                                         const unsigned char *val, size_t val_len)
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| {
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|     return mbedtls_x509_set_extension(&ctx->extensions, oid, oid_len,
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|                                       critical, val, val_len);
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| }
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| 
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| int mbedtls_x509write_crt_set_basic_constraints(mbedtls_x509write_cert *ctx,
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|                                                 int is_ca, int max_pathlen)
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| {
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|     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
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|     unsigned char buf[9];
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|     unsigned char *c = buf + sizeof(buf);
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|     size_t len = 0;
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| 
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|     memset(buf, 0, sizeof(buf));
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| 
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|     if (is_ca && max_pathlen > 127) {
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|         return MBEDTLS_ERR_X509_BAD_INPUT_DATA;
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|     }
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| 
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|     if (is_ca) {
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|         if (max_pathlen >= 0) {
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|             MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_int(&c, buf,
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|                                                              max_pathlen));
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|         }
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|         MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_bool(&c, buf, 1));
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|     }
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| 
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|     MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(&c, buf, len));
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|     MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_tag(&c, buf,
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|                                                      MBEDTLS_ASN1_CONSTRUCTED |
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|                                                      MBEDTLS_ASN1_SEQUENCE));
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| 
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|     return
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|         mbedtls_x509write_crt_set_extension(ctx, MBEDTLS_OID_BASIC_CONSTRAINTS,
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|                                             MBEDTLS_OID_SIZE(MBEDTLS_OID_BASIC_CONSTRAINTS),
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|                                             is_ca, buf + sizeof(buf) - len, len);
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| }
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| 
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| #if defined(PSA_WANT_ALG_SHA_1)
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| static int mbedtls_x509write_crt_set_key_identifier(mbedtls_x509write_cert *ctx,
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|                                                     int is_ca,
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|                                                     unsigned char tag)
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| {
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|     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
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|     unsigned char buf[MBEDTLS_MPI_MAX_SIZE * 2 + 20]; /* tag, length + 2xMPI */
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|     unsigned char *c = buf + sizeof(buf);
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|     size_t len = 0;
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|     psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
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|     size_t hash_length;
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| 
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|     memset(buf, 0, sizeof(buf));
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|     MBEDTLS_ASN1_CHK_ADD(len,
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|                          mbedtls_pk_write_pubkey(&c,
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|                                                  buf,
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|                                                  is_ca ?
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|                                                  ctx->issuer_key :
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|                                                  ctx->subject_key));
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| 
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| 
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|     status = psa_hash_compute(PSA_ALG_SHA_1,
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|                               buf + sizeof(buf) - len,
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|                               len,
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|                               buf + sizeof(buf) - 20,
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|                               20,
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|                               &hash_length);
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|     if (status != PSA_SUCCESS) {
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|         return MBEDTLS_ERR_PLATFORM_HW_ACCEL_FAILED;
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|     }
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| 
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|     c = buf + sizeof(buf) - 20;
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|     len = 20;
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| 
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|     MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(&c, buf, len));
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|     MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_tag(&c, buf, tag));
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| 
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|     if (is_ca) { // writes AuthorityKeyIdentifier sequence
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|         MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(&c, buf, len));
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|         MBEDTLS_ASN1_CHK_ADD(len,
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|                              mbedtls_asn1_write_tag(&c,
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|                                                     buf,
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|                                                     MBEDTLS_ASN1_CONSTRUCTED |
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|                                                     MBEDTLS_ASN1_SEQUENCE));
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|     }
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| 
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|     if (is_ca) {
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|         return mbedtls_x509write_crt_set_extension(ctx,
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|                                                    MBEDTLS_OID_AUTHORITY_KEY_IDENTIFIER,
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|                                                    MBEDTLS_OID_SIZE(
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|                                                        MBEDTLS_OID_AUTHORITY_KEY_IDENTIFIER),
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|                                                    0, buf + sizeof(buf) - len, len);
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|     } else {
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|         return mbedtls_x509write_crt_set_extension(ctx,
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|                                                    MBEDTLS_OID_SUBJECT_KEY_IDENTIFIER,
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|                                                    MBEDTLS_OID_SIZE(
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|                                                        MBEDTLS_OID_SUBJECT_KEY_IDENTIFIER),
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|                                                    0, buf + sizeof(buf) - len, len);
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|     }
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| }
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| 
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| int mbedtls_x509write_crt_set_subject_key_identifier(mbedtls_x509write_cert *ctx)
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| {
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|     return mbedtls_x509write_crt_set_key_identifier(ctx,
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|                                                     0,
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|                                                     MBEDTLS_ASN1_OCTET_STRING);
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| }
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| 
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| int mbedtls_x509write_crt_set_authority_key_identifier(mbedtls_x509write_cert *ctx)
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| {
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|     return mbedtls_x509write_crt_set_key_identifier(ctx,
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|                                                     1,
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|                                                     (MBEDTLS_ASN1_CONTEXT_SPECIFIC | 0));
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| }
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| #endif /* PSA_WANT_ALG_SHA_1 */
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| 
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| int mbedtls_x509write_crt_set_key_usage(mbedtls_x509write_cert *ctx,
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|                                         unsigned int key_usage)
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| {
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|     unsigned char buf[5] = { 0 }, ku[2] = { 0 };
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|     unsigned char *c;
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|     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
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|     const unsigned int allowed_bits = MBEDTLS_X509_KU_DIGITAL_SIGNATURE |
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|                                       MBEDTLS_X509_KU_NON_REPUDIATION   |
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|                                       MBEDTLS_X509_KU_KEY_ENCIPHERMENT  |
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|                                       MBEDTLS_X509_KU_DATA_ENCIPHERMENT |
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|                                       MBEDTLS_X509_KU_KEY_AGREEMENT     |
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|                                       MBEDTLS_X509_KU_KEY_CERT_SIGN     |
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|                                       MBEDTLS_X509_KU_CRL_SIGN          |
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|                                       MBEDTLS_X509_KU_ENCIPHER_ONLY     |
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|                                       MBEDTLS_X509_KU_DECIPHER_ONLY;
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| 
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|     /* Check that nothing other than the allowed flags is set */
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|     if ((key_usage & ~allowed_bits) != 0) {
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|         return MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE;
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|     }
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| 
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|     c = buf + 5;
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|     MBEDTLS_PUT_UINT16_LE(key_usage, ku, 0);
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|     ret = mbedtls_asn1_write_named_bitstring(&c, buf, ku, 9);
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| 
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|     if (ret < 0) {
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|         return ret;
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|     } else if (ret < 3 || ret > 5) {
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|         return MBEDTLS_ERR_X509_INVALID_FORMAT;
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|     }
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| 
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|     ret = mbedtls_x509write_crt_set_extension(ctx, MBEDTLS_OID_KEY_USAGE,
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|                                               MBEDTLS_OID_SIZE(MBEDTLS_OID_KEY_USAGE),
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|                                               1, c, (size_t) ret);
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|     if (ret != 0) {
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|         return ret;
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|     }
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| 
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|     return 0;
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| }
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| 
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| int mbedtls_x509write_crt_set_ext_key_usage(mbedtls_x509write_cert *ctx,
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|                                             const mbedtls_asn1_sequence *exts)
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| {
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|     unsigned char buf[256];
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|     unsigned char *c = buf + sizeof(buf);
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|     int ret;
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|     size_t len = 0;
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|     const mbedtls_asn1_sequence *last_ext = NULL;
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|     const mbedtls_asn1_sequence *ext;
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| 
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|     memset(buf, 0, sizeof(buf));
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| 
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|     /* We need at least one extension: SEQUENCE SIZE (1..MAX) OF KeyPurposeId */
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|     if (exts == NULL) {
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|         return MBEDTLS_ERR_X509_BAD_INPUT_DATA;
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|     }
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| 
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|     /* Iterate over exts backwards, so we write them out in the requested order */
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|     while (last_ext != exts) {
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|         for (ext = exts; ext->next != last_ext; ext = ext->next) {
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|         }
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|         if (ext->buf.tag != MBEDTLS_ASN1_OID) {
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|             return MBEDTLS_ERR_X509_BAD_INPUT_DATA;
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|         }
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|         MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_raw_buffer(&c, buf, ext->buf.p, ext->buf.len));
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|         MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(&c, buf, ext->buf.len));
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|         MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_tag(&c, buf, MBEDTLS_ASN1_OID));
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|         last_ext = ext;
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|     }
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| 
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|     MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(&c, buf, len));
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|     MBEDTLS_ASN1_CHK_ADD(len,
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|                          mbedtls_asn1_write_tag(&c, buf,
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|                                                 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE));
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| 
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|     return mbedtls_x509write_crt_set_extension(ctx,
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|                                                MBEDTLS_OID_EXTENDED_KEY_USAGE,
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|                                                MBEDTLS_OID_SIZE(MBEDTLS_OID_EXTENDED_KEY_USAGE),
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|                                                1, c, len);
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| }
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| 
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| int mbedtls_x509write_crt_set_ns_cert_type(mbedtls_x509write_cert *ctx,
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|                                            unsigned char ns_cert_type)
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| {
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|     unsigned char buf[4] = { 0 };
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|     unsigned char *c;
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|     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
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| 
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|     c = buf + 4;
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| 
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|     ret = mbedtls_asn1_write_named_bitstring(&c, buf, &ns_cert_type, 8);
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|     if (ret < 3 || ret > 4) {
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|         return ret;
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|     }
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| 
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|     ret = mbedtls_x509write_crt_set_extension(ctx, MBEDTLS_OID_NS_CERT_TYPE,
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|                                               MBEDTLS_OID_SIZE(MBEDTLS_OID_NS_CERT_TYPE),
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|                                               0, c, (size_t) ret);
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|     if (ret != 0) {
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|         return ret;
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|     }
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| 
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|     return 0;
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| }
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| 
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| static int x509_write_time(unsigned char **p, unsigned char *start,
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|                            const char *t, size_t size)
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| {
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|     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
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|     size_t len = 0;
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| 
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|     /*
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|      * write MBEDTLS_ASN1_UTC_TIME if year < 2050 (2 bytes shorter)
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|      */
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|     if (t[0] < '2' || (t[0] == '2' && t[1] == '0' && t[2] < '5')) {
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|         MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_raw_buffer(p, start,
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|                                                                 (const unsigned char *) t + 2,
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|                                                                 size - 2));
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|         MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(p, start, len));
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|         MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_tag(p, start,
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|                                                          MBEDTLS_ASN1_UTC_TIME));
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|     } else {
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|         MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_raw_buffer(p, start,
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|                                                                 (const unsigned char *) t,
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|                                                                 size));
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|         MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(p, start, len));
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|         MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_tag(p, start,
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|                                                          MBEDTLS_ASN1_GENERALIZED_TIME));
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|     }
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| 
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|     return (int) len;
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| }
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| 
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| int mbedtls_x509write_crt_der(mbedtls_x509write_cert *ctx,
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|                               unsigned char *buf, size_t size)
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| {
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|     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
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|     const char *sig_oid;
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|     size_t sig_oid_len = 0;
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|     unsigned char *c, *c2;
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|     unsigned char sig[MBEDTLS_PK_SIGNATURE_MAX_SIZE];
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|     size_t hash_length = 0;
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|     unsigned char hash[MBEDTLS_MD_MAX_SIZE];
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|     psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
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|     psa_algorithm_t psa_algorithm;
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| 
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|     size_t sub_len = 0, pub_len = 0, sig_and_oid_len = 0, sig_len;
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|     size_t len = 0;
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|     mbedtls_pk_type_t pk_alg;
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|     int write_sig_null_par;
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| 
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|     /*
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|      * Prepare data to be signed at the end of the target buffer
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|      */
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|     c = buf + size;
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| 
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|     /* Signature algorithm needed in TBS, and later for actual signature */
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| 
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|     /* There's no direct way of extracting a signature algorithm
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|      * (represented as an element of mbedtls_pk_type_t) from a PK instance. */
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|     if (mbedtls_pk_can_do(ctx->issuer_key, MBEDTLS_PK_RSA)) {
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|         pk_alg = MBEDTLS_PK_RSA;
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|     } else if (mbedtls_pk_can_do(ctx->issuer_key, MBEDTLS_PK_ECDSA)) {
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|         pk_alg = MBEDTLS_PK_ECDSA;
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|     } else {
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|         return MBEDTLS_ERR_X509_INVALID_ALG;
 | |
|     }
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| 
 | |
|     if ((ret = mbedtls_x509_oid_get_oid_by_sig_alg((mbedtls_pk_sigalg_t) pk_alg, ctx->md_alg,
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|                                                    &sig_oid, &sig_oid_len)) != 0) {
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|         return ret;
 | |
|     }
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| 
 | |
|     /*
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|      *  Extensions  ::=  SEQUENCE SIZE (1..MAX) OF Extension
 | |
|      */
 | |
| 
 | |
|     /* Only for v3 */
 | |
|     if (ctx->version == MBEDTLS_X509_CRT_VERSION_3) {
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|         MBEDTLS_ASN1_CHK_ADD(len,
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|                              mbedtls_x509_write_extensions(&c,
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|                                                            buf, ctx->extensions));
 | |
|         MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(&c, buf, len));
 | |
|         MBEDTLS_ASN1_CHK_ADD(len,
 | |
|                              mbedtls_asn1_write_tag(&c, buf,
 | |
|                                                     MBEDTLS_ASN1_CONSTRUCTED |
 | |
|                                                     MBEDTLS_ASN1_SEQUENCE));
 | |
|         MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(&c, buf, len));
 | |
|         MBEDTLS_ASN1_CHK_ADD(len,
 | |
|                              mbedtls_asn1_write_tag(&c, buf,
 | |
|                                                     MBEDTLS_ASN1_CONTEXT_SPECIFIC |
 | |
|                                                     MBEDTLS_ASN1_CONSTRUCTED | 3));
 | |
|     }
 | |
| 
 | |
|     /*
 | |
|      *  SubjectPublicKeyInfo
 | |
|      */
 | |
|     MBEDTLS_ASN1_CHK_ADD(pub_len,
 | |
|                          mbedtls_pk_write_pubkey_der(ctx->subject_key,
 | |
|                                                      buf, (size_t) (c - buf)));
 | |
|     c -= pub_len;
 | |
|     len += pub_len;
 | |
| 
 | |
|     /*
 | |
|      *  Subject  ::=  Name
 | |
|      */
 | |
|     MBEDTLS_ASN1_CHK_ADD(len,
 | |
|                          mbedtls_x509_write_names(&c, buf,
 | |
|                                                   ctx->subject));
 | |
| 
 | |
|     /*
 | |
|      *  Validity ::= SEQUENCE {
 | |
|      *       notBefore      Time,
 | |
|      *       notAfter       Time }
 | |
|      */
 | |
|     sub_len = 0;
 | |
| 
 | |
|     MBEDTLS_ASN1_CHK_ADD(sub_len,
 | |
|                          x509_write_time(&c, buf, ctx->not_after,
 | |
|                                          MBEDTLS_X509_RFC5280_UTC_TIME_LEN));
 | |
| 
 | |
|     MBEDTLS_ASN1_CHK_ADD(sub_len,
 | |
|                          x509_write_time(&c, buf, ctx->not_before,
 | |
|                                          MBEDTLS_X509_RFC5280_UTC_TIME_LEN));
 | |
| 
 | |
|     len += sub_len;
 | |
|     MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(&c, buf, sub_len));
 | |
|     MBEDTLS_ASN1_CHK_ADD(len,
 | |
|                          mbedtls_asn1_write_tag(&c, buf,
 | |
|                                                 MBEDTLS_ASN1_CONSTRUCTED |
 | |
|                                                 MBEDTLS_ASN1_SEQUENCE));
 | |
| 
 | |
|     /*
 | |
|      *  Issuer  ::=  Name
 | |
|      */
 | |
|     MBEDTLS_ASN1_CHK_ADD(len, mbedtls_x509_write_names(&c, buf,
 | |
|                                                        ctx->issuer));
 | |
| 
 | |
|     /*
 | |
|      *  Signature   ::=  AlgorithmIdentifier
 | |
|      */
 | |
|     if (pk_alg == MBEDTLS_PK_ECDSA) {
 | |
|         /*
 | |
|          * The AlgorithmIdentifier's parameters field must be absent for DSA/ECDSA signature
 | |
|          * algorithms, see https://www.rfc-editor.org/rfc/rfc5480#page-17 and
 | |
|          * https://www.rfc-editor.org/rfc/rfc5758#section-3.
 | |
|          */
 | |
|         write_sig_null_par = 0;
 | |
|     } else {
 | |
|         write_sig_null_par = 1;
 | |
|     }
 | |
|     MBEDTLS_ASN1_CHK_ADD(len,
 | |
|                          mbedtls_asn1_write_algorithm_identifier_ext(&c, buf,
 | |
|                                                                      sig_oid, strlen(sig_oid),
 | |
|                                                                      0, write_sig_null_par));
 | |
| 
 | |
|     /*
 | |
|      *  Serial   ::=  INTEGER
 | |
|      *
 | |
|      * Written data is:
 | |
|      * - "ctx->serial_len" bytes for the raw serial buffer
 | |
|      *   - if MSb of "serial" is 1, then prepend an extra 0x00 byte
 | |
|      * - 1 byte for the length
 | |
|      * - 1 byte for the TAG
 | |
|      */
 | |
|     MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_raw_buffer(&c, buf,
 | |
|                                                             ctx->serial, ctx->serial_len));
 | |
|     if (*c & 0x80) {
 | |
|         if (c - buf < 1) {
 | |
|             return MBEDTLS_ERR_X509_BUFFER_TOO_SMALL;
 | |
|         }
 | |
|         *(--c) = 0x0;
 | |
|         len++;
 | |
|         MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(&c, buf,
 | |
|                                                          ctx->serial_len + 1));
 | |
|     } else {
 | |
|         MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(&c, buf,
 | |
|                                                          ctx->serial_len));
 | |
|     }
 | |
|     MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_tag(&c, buf,
 | |
|                                                      MBEDTLS_ASN1_INTEGER));
 | |
| 
 | |
|     /*
 | |
|      *  Version  ::=  INTEGER  {  v1(0), v2(1), v3(2)  }
 | |
|      */
 | |
| 
 | |
|     /* Can be omitted for v1 */
 | |
|     if (ctx->version != MBEDTLS_X509_CRT_VERSION_1) {
 | |
|         sub_len = 0;
 | |
|         MBEDTLS_ASN1_CHK_ADD(sub_len,
 | |
|                              mbedtls_asn1_write_int(&c, buf, ctx->version));
 | |
|         len += sub_len;
 | |
|         MBEDTLS_ASN1_CHK_ADD(len,
 | |
|                              mbedtls_asn1_write_len(&c, buf, sub_len));
 | |
|         MBEDTLS_ASN1_CHK_ADD(len,
 | |
|                              mbedtls_asn1_write_tag(&c, buf,
 | |
|                                                     MBEDTLS_ASN1_CONTEXT_SPECIFIC |
 | |
|                                                     MBEDTLS_ASN1_CONSTRUCTED | 0));
 | |
|     }
 | |
| 
 | |
|     MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(&c, buf, len));
 | |
|     MBEDTLS_ASN1_CHK_ADD(len,
 | |
|                          mbedtls_asn1_write_tag(&c, buf, MBEDTLS_ASN1_CONSTRUCTED |
 | |
|                                                 MBEDTLS_ASN1_SEQUENCE));
 | |
| 
 | |
|     /*
 | |
|      * Make signature
 | |
|      */
 | |
| 
 | |
|     /* Compute hash of CRT. */
 | |
|     psa_algorithm = mbedtls_md_psa_alg_from_type(ctx->md_alg);
 | |
| 
 | |
|     status = psa_hash_compute(psa_algorithm,
 | |
|                               c,
 | |
|                               len,
 | |
|                               hash,
 | |
|                               sizeof(hash),
 | |
|                               &hash_length);
 | |
|     if (status != PSA_SUCCESS) {
 | |
|         return MBEDTLS_ERR_PLATFORM_HW_ACCEL_FAILED;
 | |
|     }
 | |
| 
 | |
| 
 | |
|     if ((ret = mbedtls_pk_sign(ctx->issuer_key, ctx->md_alg,
 | |
|                                hash, hash_length, sig, sizeof(sig), &sig_len)) != 0) {
 | |
|         return ret;
 | |
|     }
 | |
| 
 | |
|     /* Move CRT to the front of the buffer to have space
 | |
|      * for the signature. */
 | |
|     memmove(buf, c, len);
 | |
|     c = buf + len;
 | |
| 
 | |
|     /* Add signature at the end of the buffer,
 | |
|      * making sure that it doesn't underflow
 | |
|      * into the CRT buffer. */
 | |
|     c2 = buf + size;
 | |
|     MBEDTLS_ASN1_CHK_ADD(sig_and_oid_len, mbedtls_x509_write_sig(&c2, c,
 | |
|                                                                  sig_oid, sig_oid_len,
 | |
|                                                                  sig, sig_len,
 | |
|                                                                  (mbedtls_pk_sigalg_t) pk_alg));
 | |
| 
 | |
|     /*
 | |
|      * Memory layout after this step:
 | |
|      *
 | |
|      * buf       c=buf+len                c2            buf+size
 | |
|      * [CRT0,...,CRTn, UNUSED, ..., UNUSED, SIG0, ..., SIGm]
 | |
|      */
 | |
| 
 | |
|     /* Move raw CRT to just before the signature. */
 | |
|     c = c2 - len;
 | |
|     memmove(c, buf, len);
 | |
| 
 | |
|     len += sig_and_oid_len;
 | |
|     MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(&c, buf, len));
 | |
|     MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_tag(&c, buf,
 | |
|                                                      MBEDTLS_ASN1_CONSTRUCTED |
 | |
|                                                      MBEDTLS_ASN1_SEQUENCE));
 | |
| 
 | |
|     return (int) len;
 | |
| }
 | |
| 
 | |
| #define PEM_BEGIN_CRT           "-----BEGIN CERTIFICATE-----\n"
 | |
| #define PEM_END_CRT             "-----END CERTIFICATE-----\n"
 | |
| 
 | |
| #if defined(MBEDTLS_PEM_WRITE_C)
 | |
| int mbedtls_x509write_crt_pem(mbedtls_x509write_cert *crt,
 | |
|                               unsigned char *buf, size_t size)
 | |
| {
 | |
|     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
 | |
|     size_t olen;
 | |
| 
 | |
|     if ((ret = mbedtls_x509write_crt_der(crt, buf, size)) < 0) {
 | |
|         return ret;
 | |
|     }
 | |
| 
 | |
|     if ((ret = mbedtls_pem_write_buffer(PEM_BEGIN_CRT, PEM_END_CRT,
 | |
|                                         buf + size - ret, ret,
 | |
|                                         buf, size, &olen)) != 0) {
 | |
|         return ret;
 | |
|     }
 | |
| 
 | |
|     return 0;
 | |
| }
 | |
| #endif /* MBEDTLS_PEM_WRITE_C */
 | |
| 
 | |
| #endif /* MBEDTLS_X509_CRT_WRITE_C */
 |