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			682 lines
		
	
	
		
			24 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			682 lines
		
	
	
		
			24 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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#include "common.h"
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#if defined(MBEDTLS_X509_CRT_WRITE_C)
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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 "mbedtls/platform.h"
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#include "mbedtls/platform_util.h"
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#include "mbedtls/md.h"
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#include <string.h>
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#include <stdint.h>
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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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#if defined(MBEDTLS_USE_PSA_CRYPTO)
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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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#endif /* MBEDTLS_USE_PSA_CRYPTO */
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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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    ctx->version = MBEDTLS_X509_CRT_VERSION_3;
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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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    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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    mbedtls_platform_zeroize(ctx, sizeof(mbedtls_x509write_cert));
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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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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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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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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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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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    return mbedtls_x509_string_to_names(&ctx->subject, subject_name);
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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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    return mbedtls_x509_string_to_names(&ctx->issuer, issuer_name);
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}
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#if defined(MBEDTLS_BIGNUM_C) && !defined(MBEDTLS_DEPRECATED_REMOVED)
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int mbedtls_x509write_crt_set_serial(mbedtls_x509write_cert *ctx,
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                                     const mbedtls_mpi *serial)
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{
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    int ret;
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    size_t tmp_len;
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    /* Ensure that the MPI value fits into the buffer */
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    tmp_len = mbedtls_mpi_size(serial);
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    if (tmp_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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    ctx->serial_len = tmp_len;
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    ret = mbedtls_mpi_write_binary(serial, ctx->serial, tmp_len);
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    if (ret < 0) {
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        return ret;
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    }
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    return 0;
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}
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#endif // MBEDTLS_BIGNUM_C && !MBEDTLS_DEPRECATED_REMOVED
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int mbedtls_x509write_crt_set_serial_raw(mbedtls_x509write_cert *ctx,
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                                         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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    ctx->serial_len = serial_len;
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    memcpy(ctx->serial, serial, serial_len);
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    return 0;
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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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    return 0;
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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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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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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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    memset(buf, 0, sizeof(buf));
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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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    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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    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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    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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#if defined(MBEDTLS_MD_CAN_SHA1)
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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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#if defined(MBEDTLS_USE_PSA_CRYPTO)
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    psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
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    size_t hash_length;
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#endif /* MBEDTLS_USE_PSA_CRYPTO */
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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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#if defined(MBEDTLS_USE_PSA_CRYPTO)
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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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#else
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    ret = mbedtls_md(mbedtls_md_info_from_type(MBEDTLS_MD_SHA1),
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                     buf + sizeof(buf) - len, len,
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                     buf + sizeof(buf) - 20);
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    if (ret != 0) {
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        return ret;
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    }
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#endif /* MBEDTLS_USE_PSA_CRYPTO */
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    c = buf + sizeof(buf) - 20;
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    len = 20;
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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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    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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    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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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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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 /* MBEDTLS_MD_CAN_SHA1 */
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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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    /* 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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    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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    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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    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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    return 0;
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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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    memset(buf, 0, sizeof(buf));
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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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    /* 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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    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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    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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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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    c = buf + 4;
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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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    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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    return 0;
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}
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 | 
						|
static int x509_write_time(unsigned char **p, unsigned char *start,
 | 
						|
                           const char *t, size_t size)
 | 
						|
{
 | 
						|
    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
 | 
						|
    size_t len = 0;
 | 
						|
 | 
						|
    /*
 | 
						|
     * write MBEDTLS_ASN1_UTC_TIME if year < 2050 (2 bytes shorter)
 | 
						|
     */
 | 
						|
    if (t[0] < '2' || (t[0] == '2' && t[1] == '0' && t[2] < '5')) {
 | 
						|
        MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_raw_buffer(p, start,
 | 
						|
                                                                (const unsigned char *) t + 2,
 | 
						|
                                                                size - 2));
 | 
						|
        MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(p, start, len));
 | 
						|
        MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_tag(p, start,
 | 
						|
                                                         MBEDTLS_ASN1_UTC_TIME));
 | 
						|
    } else {
 | 
						|
        MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_raw_buffer(p, start,
 | 
						|
                                                                (const unsigned char *) t,
 | 
						|
                                                                size));
 | 
						|
        MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(p, start, len));
 | 
						|
        MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_tag(p, start,
 | 
						|
                                                         MBEDTLS_ASN1_GENERALIZED_TIME));
 | 
						|
    }
 | 
						|
 | 
						|
    return (int) len;
 | 
						|
}
 | 
						|
 | 
						|
int mbedtls_x509write_crt_der(mbedtls_x509write_cert *ctx,
 | 
						|
                              unsigned char *buf, size_t size,
 | 
						|
                              int (*f_rng)(void *, unsigned char *, size_t),
 | 
						|
                              void *p_rng)
 | 
						|
{
 | 
						|
    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
 | 
						|
    const char *sig_oid;
 | 
						|
    size_t sig_oid_len = 0;
 | 
						|
    unsigned char *c, *c2;
 | 
						|
    unsigned char sig[MBEDTLS_PK_SIGNATURE_MAX_SIZE];
 | 
						|
    size_t hash_length = 0;
 | 
						|
    unsigned char hash[MBEDTLS_MD_MAX_SIZE];
 | 
						|
#if defined(MBEDTLS_USE_PSA_CRYPTO)
 | 
						|
    psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
 | 
						|
    psa_algorithm_t psa_algorithm;
 | 
						|
#endif /* MBEDTLS_USE_PSA_CRYPTO */
 | 
						|
 | 
						|
    size_t sub_len = 0, pub_len = 0, sig_and_oid_len = 0, sig_len;
 | 
						|
    size_t len = 0;
 | 
						|
    mbedtls_pk_type_t pk_alg;
 | 
						|
    int write_sig_null_par;
 | 
						|
 | 
						|
    /*
 | 
						|
     * Prepare data to be signed at the end of the target buffer
 | 
						|
     */
 | 
						|
    c = buf + size;
 | 
						|
 | 
						|
    /* Signature algorithm needed in TBS, and later for actual signature */
 | 
						|
 | 
						|
    /* There's no direct way of extracting a signature algorithm
 | 
						|
     * (represented as an element of mbedtls_pk_type_t) from a PK instance. */
 | 
						|
    if (mbedtls_pk_can_do(ctx->issuer_key, MBEDTLS_PK_RSA)) {
 | 
						|
        pk_alg = MBEDTLS_PK_RSA;
 | 
						|
    } else if (mbedtls_pk_can_do(ctx->issuer_key, MBEDTLS_PK_ECDSA)) {
 | 
						|
        pk_alg = MBEDTLS_PK_ECDSA;
 | 
						|
    } else {
 | 
						|
        return MBEDTLS_ERR_X509_INVALID_ALG;
 | 
						|
    }
 | 
						|
 | 
						|
    if ((ret = mbedtls_oid_get_oid_by_sig_alg(pk_alg, ctx->md_alg,
 | 
						|
                                              &sig_oid, &sig_oid_len)) != 0) {
 | 
						|
        return ret;
 | 
						|
    }
 | 
						|
 | 
						|
    /*
 | 
						|
     *  Extensions  ::=  SEQUENCE SIZE (1..MAX) OF Extension
 | 
						|
     */
 | 
						|
 | 
						|
    /* Only for v3 */
 | 
						|
    if (ctx->version == MBEDTLS_X509_CRT_VERSION_3) {
 | 
						|
        MBEDTLS_ASN1_CHK_ADD(len,
 | 
						|
                             mbedtls_x509_write_extensions(&c,
 | 
						|
                                                           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. */
 | 
						|
#if defined(MBEDTLS_USE_PSA_CRYPTO)
 | 
						|
    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;
 | 
						|
    }
 | 
						|
#else
 | 
						|
    if ((ret = mbedtls_md(mbedtls_md_info_from_type(ctx->md_alg), c,
 | 
						|
                          len, hash)) != 0) {
 | 
						|
        return ret;
 | 
						|
    }
 | 
						|
#endif /* MBEDTLS_USE_PSA_CRYPTO */
 | 
						|
 | 
						|
 | 
						|
    if ((ret = mbedtls_pk_sign(ctx->issuer_key, ctx->md_alg,
 | 
						|
                               hash, hash_length, sig, sizeof(sig), &sig_len,
 | 
						|
                               f_rng, p_rng)) != 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, 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 (*f_rng)(void *, unsigned char *, size_t),
 | 
						|
                              void *p_rng)
 | 
						|
{
 | 
						|
    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
 | 
						|
    size_t olen;
 | 
						|
 | 
						|
    if ((ret = mbedtls_x509write_crt_der(crt, buf, size,
 | 
						|
                                         f_rng, p_rng)) < 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 */
 |