| /* |
| * X.509 certificate writing |
| * |
| * Copyright The Mbed TLS Contributors |
| * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later |
| */ |
| /* |
| * References: |
| * - certificates: RFC 5280, updated by RFC 6818 |
| * - CSRs: PKCS#10 v1.7 aka RFC 2986 |
| * - attributes: PKCS#9 v2.0 aka RFC 2985 |
| */ |
| |
| #include "common.h" |
| |
| #if defined(MBEDTLS_X509_CRT_WRITE_C) |
| |
| #include "mbedtls/x509_crt.h" |
| #include "mbedtls/asn1write.h" |
| #include "mbedtls/error.h" |
| #include "mbedtls/oid.h" |
| #include "mbedtls/platform.h" |
| #include "mbedtls/platform_util.h" |
| #include "mbedtls/md.h" |
| |
| #include <string.h> |
| #include <stdint.h> |
| |
| #if defined(MBEDTLS_PEM_WRITE_C) |
| #include "mbedtls/pem.h" |
| #endif /* MBEDTLS_PEM_WRITE_C */ |
| |
| #if defined(MBEDTLS_USE_PSA_CRYPTO) |
| #include "psa/crypto.h" |
| #include "psa_util_internal.h" |
| #include "md_psa.h" |
| #endif /* MBEDTLS_USE_PSA_CRYPTO */ |
| |
| void mbedtls_x509write_crt_init(mbedtls_x509write_cert *ctx) |
| { |
| memset(ctx, 0, sizeof(mbedtls_x509write_cert)); |
| |
| ctx->version = MBEDTLS_X509_CRT_VERSION_3; |
| } |
| |
| void mbedtls_x509write_crt_free(mbedtls_x509write_cert *ctx) |
| { |
| mbedtls_asn1_free_named_data_list(&ctx->subject); |
| mbedtls_asn1_free_named_data_list(&ctx->issuer); |
| mbedtls_asn1_free_named_data_list(&ctx->extensions); |
| |
| mbedtls_platform_zeroize(ctx, sizeof(mbedtls_x509write_cert)); |
| } |
| |
| void mbedtls_x509write_crt_set_version(mbedtls_x509write_cert *ctx, |
| int version) |
| { |
| ctx->version = version; |
| } |
| |
| void mbedtls_x509write_crt_set_md_alg(mbedtls_x509write_cert *ctx, |
| mbedtls_md_type_t md_alg) |
| { |
| ctx->md_alg = md_alg; |
| } |
| |
| void mbedtls_x509write_crt_set_subject_key(mbedtls_x509write_cert *ctx, |
| mbedtls_pk_context *key) |
| { |
| ctx->subject_key = key; |
| } |
| |
| void mbedtls_x509write_crt_set_issuer_key(mbedtls_x509write_cert *ctx, |
| mbedtls_pk_context *key) |
| { |
| ctx->issuer_key = key; |
| } |
| |
| int mbedtls_x509write_crt_set_subject_name(mbedtls_x509write_cert *ctx, |
| const char *subject_name) |
| { |
| return mbedtls_x509_string_to_names(&ctx->subject, subject_name); |
| } |
| |
| int mbedtls_x509write_crt_set_issuer_name(mbedtls_x509write_cert *ctx, |
| const char *issuer_name) |
| { |
| return mbedtls_x509_string_to_names(&ctx->issuer, issuer_name); |
| } |
| |
| #if defined(MBEDTLS_BIGNUM_C) && !defined(MBEDTLS_DEPRECATED_REMOVED) |
| int mbedtls_x509write_crt_set_serial(mbedtls_x509write_cert *ctx, |
| const mbedtls_mpi *serial) |
| { |
| int ret; |
| size_t tmp_len; |
| |
| /* Ensure that the MPI value fits into the buffer */ |
| tmp_len = mbedtls_mpi_size(serial); |
| if (tmp_len > MBEDTLS_X509_RFC5280_MAX_SERIAL_LEN) { |
| return MBEDTLS_ERR_X509_BAD_INPUT_DATA; |
| } |
| |
| ctx->serial_len = tmp_len; |
| |
| ret = mbedtls_mpi_write_binary(serial, ctx->serial, tmp_len); |
| if (ret < 0) { |
| return ret; |
| } |
| |
| return 0; |
| } |
| #endif // MBEDTLS_BIGNUM_C && !MBEDTLS_DEPRECATED_REMOVED |
| |
| int mbedtls_x509write_crt_set_serial_raw(mbedtls_x509write_cert *ctx, |
| unsigned char *serial, size_t serial_len) |
| { |
| if (serial_len > MBEDTLS_X509_RFC5280_MAX_SERIAL_LEN) { |
| return MBEDTLS_ERR_X509_BAD_INPUT_DATA; |
| } |
| |
| ctx->serial_len = serial_len; |
| memcpy(ctx->serial, serial, serial_len); |
| |
| return 0; |
| } |
| |
| int mbedtls_x509write_crt_set_validity(mbedtls_x509write_cert *ctx, |
| const char *not_before, |
| const char *not_after) |
| { |
| if (strlen(not_before) != MBEDTLS_X509_RFC5280_UTC_TIME_LEN - 1 || |
| strlen(not_after) != MBEDTLS_X509_RFC5280_UTC_TIME_LEN - 1) { |
| return MBEDTLS_ERR_X509_BAD_INPUT_DATA; |
| } |
| strncpy(ctx->not_before, not_before, MBEDTLS_X509_RFC5280_UTC_TIME_LEN); |
| strncpy(ctx->not_after, not_after, MBEDTLS_X509_RFC5280_UTC_TIME_LEN); |
| ctx->not_before[MBEDTLS_X509_RFC5280_UTC_TIME_LEN - 1] = 'Z'; |
| ctx->not_after[MBEDTLS_X509_RFC5280_UTC_TIME_LEN - 1] = 'Z'; |
| |
| return 0; |
| } |
| |
| int mbedtls_x509write_crt_set_subject_alternative_name(mbedtls_x509write_cert *ctx, |
| const mbedtls_x509_san_list *san_list) |
| { |
| return mbedtls_x509_write_set_san_common(&ctx->extensions, san_list); |
| } |
| |
| |
| int mbedtls_x509write_crt_set_extension(mbedtls_x509write_cert *ctx, |
| const char *oid, size_t oid_len, |
| int critical, |
| const unsigned char *val, size_t val_len) |
| { |
| return mbedtls_x509_set_extension(&ctx->extensions, oid, oid_len, |
| critical, val, val_len); |
| } |
| |
| int mbedtls_x509write_crt_set_basic_constraints(mbedtls_x509write_cert *ctx, |
| int is_ca, int max_pathlen) |
| { |
| int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; |
| unsigned char buf[9]; |
| unsigned char *c = buf + sizeof(buf); |
| size_t len = 0; |
| |
| memset(buf, 0, sizeof(buf)); |
| |
| if (is_ca && max_pathlen > 127) { |
| return MBEDTLS_ERR_X509_BAD_INPUT_DATA; |
| } |
| |
| if (is_ca) { |
| if (max_pathlen >= 0) { |
| MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_int(&c, buf, |
| max_pathlen)); |
| } |
| MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_bool(&c, buf, 1)); |
| } |
| |
| 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 |
| mbedtls_x509write_crt_set_extension(ctx, MBEDTLS_OID_BASIC_CONSTRAINTS, |
| MBEDTLS_OID_SIZE(MBEDTLS_OID_BASIC_CONSTRAINTS), |
| is_ca, buf + sizeof(buf) - len, len); |
| } |
| |
| #if defined(MBEDTLS_MD_CAN_SHA1) |
| static int mbedtls_x509write_crt_set_key_identifier(mbedtls_x509write_cert *ctx, |
| int is_ca, |
| unsigned char tag) |
| { |
| int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; |
| unsigned char buf[MBEDTLS_MPI_MAX_SIZE * 2 + 20]; /* tag, length + 2xMPI */ |
| unsigned char *c = buf + sizeof(buf); |
| size_t len = 0; |
| #if defined(MBEDTLS_USE_PSA_CRYPTO) |
| psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED; |
| size_t hash_length; |
| #endif /* MBEDTLS_USE_PSA_CRYPTO */ |
| |
| memset(buf, 0, sizeof(buf)); |
| MBEDTLS_ASN1_CHK_ADD(len, |
| mbedtls_pk_write_pubkey(&c, |
| buf, |
| is_ca ? |
| ctx->issuer_key : |
| ctx->subject_key)); |
| |
| |
| #if defined(MBEDTLS_USE_PSA_CRYPTO) |
| status = psa_hash_compute(PSA_ALG_SHA_1, |
| buf + sizeof(buf) - len, |
| len, |
| buf + sizeof(buf) - 20, |
| 20, |
| &hash_length); |
| if (status != PSA_SUCCESS) { |
| return MBEDTLS_ERR_PLATFORM_HW_ACCEL_FAILED; |
| } |
| #else |
| ret = mbedtls_md(mbedtls_md_info_from_type(MBEDTLS_MD_SHA1), |
| buf + sizeof(buf) - len, len, |
| buf + sizeof(buf) - 20); |
| if (ret != 0) { |
| return ret; |
| } |
| #endif /* MBEDTLS_USE_PSA_CRYPTO */ |
| |
| c = buf + sizeof(buf) - 20; |
| len = 20; |
| |
| MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(&c, buf, len)); |
| MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_tag(&c, buf, tag)); |
| |
| if (is_ca) { // writes AuthorityKeyIdentifier 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_CONSTRUCTED | |
| MBEDTLS_ASN1_SEQUENCE)); |
| } |
| |
| if (is_ca) { |
| return mbedtls_x509write_crt_set_extension(ctx, |
| MBEDTLS_OID_AUTHORITY_KEY_IDENTIFIER, |
| MBEDTLS_OID_SIZE( |
| MBEDTLS_OID_AUTHORITY_KEY_IDENTIFIER), |
| 0, buf + sizeof(buf) - len, len); |
| } else { |
| return mbedtls_x509write_crt_set_extension(ctx, |
| MBEDTLS_OID_SUBJECT_KEY_IDENTIFIER, |
| MBEDTLS_OID_SIZE( |
| MBEDTLS_OID_SUBJECT_KEY_IDENTIFIER), |
| 0, buf + sizeof(buf) - len, len); |
| } |
| } |
| |
| int mbedtls_x509write_crt_set_subject_key_identifier(mbedtls_x509write_cert *ctx) |
| { |
| return mbedtls_x509write_crt_set_key_identifier(ctx, |
| 0, |
| MBEDTLS_ASN1_OCTET_STRING); |
| } |
| |
| int mbedtls_x509write_crt_set_authority_key_identifier(mbedtls_x509write_cert *ctx) |
| { |
| return mbedtls_x509write_crt_set_key_identifier(ctx, |
| 1, |
| (MBEDTLS_ASN1_CONTEXT_SPECIFIC | 0)); |
| } |
| #endif /* MBEDTLS_MD_CAN_SHA1 */ |
| |
| int mbedtls_x509write_crt_set_key_usage(mbedtls_x509write_cert *ctx, |
| unsigned int key_usage) |
| { |
| unsigned char buf[5] = { 0 }, ku[2] = { 0 }; |
| unsigned char *c; |
| int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; |
| const unsigned int allowed_bits = MBEDTLS_X509_KU_DIGITAL_SIGNATURE | |
| MBEDTLS_X509_KU_NON_REPUDIATION | |
| MBEDTLS_X509_KU_KEY_ENCIPHERMENT | |
| MBEDTLS_X509_KU_DATA_ENCIPHERMENT | |
| MBEDTLS_X509_KU_KEY_AGREEMENT | |
| MBEDTLS_X509_KU_KEY_CERT_SIGN | |
| MBEDTLS_X509_KU_CRL_SIGN | |
| MBEDTLS_X509_KU_ENCIPHER_ONLY | |
| MBEDTLS_X509_KU_DECIPHER_ONLY; |
| |
| /* Check that nothing other than the allowed flags is set */ |
| if ((key_usage & ~allowed_bits) != 0) { |
| return MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE; |
| } |
| |
| c = buf + 5; |
| MBEDTLS_PUT_UINT16_LE(key_usage, ku, 0); |
| ret = mbedtls_asn1_write_named_bitstring(&c, buf, ku, 9); |
| |
| if (ret < 0) { |
| return ret; |
| } else if (ret < 3 || ret > 5) { |
| return MBEDTLS_ERR_X509_INVALID_FORMAT; |
| } |
| |
| ret = mbedtls_x509write_crt_set_extension(ctx, MBEDTLS_OID_KEY_USAGE, |
| MBEDTLS_OID_SIZE(MBEDTLS_OID_KEY_USAGE), |
| 1, c, (size_t) ret); |
| if (ret != 0) { |
| return ret; |
| } |
| |
| return 0; |
| } |
| |
| int mbedtls_x509write_crt_set_ext_key_usage(mbedtls_x509write_cert *ctx, |
| const mbedtls_asn1_sequence *exts) |
| { |
| unsigned char buf[256]; |
| unsigned char *c = buf + sizeof(buf); |
| int ret; |
| size_t len = 0; |
| const mbedtls_asn1_sequence *last_ext = NULL; |
| const mbedtls_asn1_sequence *ext; |
| |
| memset(buf, 0, sizeof(buf)); |
| |
| /* We need at least one extension: SEQUENCE SIZE (1..MAX) OF KeyPurposeId */ |
| if (exts == NULL) { |
| return MBEDTLS_ERR_X509_BAD_INPUT_DATA; |
| } |
| |
| /* Iterate over exts backwards, so we write them out in the requested order */ |
| while (last_ext != exts) { |
| for (ext = exts; ext->next != last_ext; ext = ext->next) { |
| } |
| if (ext->buf.tag != MBEDTLS_ASN1_OID) { |
| return MBEDTLS_ERR_X509_BAD_INPUT_DATA; |
| } |
| MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_raw_buffer(&c, buf, ext->buf.p, ext->buf.len)); |
| MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(&c, buf, ext->buf.len)); |
| MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_tag(&c, buf, MBEDTLS_ASN1_OID)); |
| last_ext = ext; |
| } |
| |
| 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 mbedtls_x509write_crt_set_extension(ctx, |
| MBEDTLS_OID_EXTENDED_KEY_USAGE, |
| MBEDTLS_OID_SIZE(MBEDTLS_OID_EXTENDED_KEY_USAGE), |
| 1, c, len); |
| } |
| |
| int mbedtls_x509write_crt_set_ns_cert_type(mbedtls_x509write_cert *ctx, |
| unsigned char ns_cert_type) |
| { |
| unsigned char buf[4] = { 0 }; |
| unsigned char *c; |
| int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; |
| |
| c = buf + 4; |
| |
| ret = mbedtls_asn1_write_named_bitstring(&c, buf, &ns_cert_type, 8); |
| if (ret < 3 || ret > 4) { |
| return ret; |
| } |
| |
| ret = mbedtls_x509write_crt_set_extension(ctx, MBEDTLS_OID_NS_CERT_TYPE, |
| MBEDTLS_OID_SIZE(MBEDTLS_OID_NS_CERT_TYPE), |
| 0, c, (size_t) ret); |
| if (ret != 0) { |
| return ret; |
| } |
| |
| return 0; |
| } |
| |
| 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, 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 */ |