| /* |
| * Public Key layer for writing key files and structures |
| * |
| * Copyright The Mbed TLS Contributors |
| * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later |
| */ |
| |
| #include "common.h" |
| |
| #if defined(MBEDTLS_PK_WRITE_C) |
| |
| #include "mbedtls/pk.h" |
| #include "mbedtls/asn1write.h" |
| #include "mbedtls/oid.h" |
| #include "mbedtls/platform_util.h" |
| #include "mbedtls/error.h" |
| #include "pk_internal.h" |
| |
| #include <string.h> |
| |
| #if defined(MBEDTLS_ECP_C) |
| #include "mbedtls/bignum.h" |
| #include "mbedtls/ecp.h" |
| #include "mbedtls/platform_util.h" |
| #endif |
| #if defined(MBEDTLS_PK_HAVE_ECC_KEYS) |
| #include "pk_internal.h" |
| #endif |
| #if defined(MBEDTLS_RSA_C) || defined(MBEDTLS_PK_HAVE_ECC_KEYS) |
| #include "pkwrite.h" |
| #endif |
| #if defined(MBEDTLS_PEM_WRITE_C) |
| #include "mbedtls/pem.h" |
| #endif |
| #if defined(MBEDTLS_RSA_C) |
| #include "rsa_internal.h" |
| #endif |
| |
| #if defined(MBEDTLS_USE_PSA_CRYPTO) |
| #include "psa/crypto.h" |
| #include "psa_util_internal.h" |
| #endif |
| #include "mbedtls/platform.h" |
| |
| /* Helpers for properly sizing buffers aimed at holding public keys or |
| * key-pairs based on build symbols. */ |
| #if defined(MBEDTLS_PK_USE_PSA_EC_DATA) |
| #define PK_MAX_EC_PUBLIC_KEY_SIZE PSA_EXPORT_PUBLIC_KEY_MAX_SIZE |
| #define PK_MAX_EC_KEY_PAIR_SIZE MBEDTLS_PSA_MAX_EC_KEY_PAIR_LENGTH |
| #elif defined(MBEDTLS_USE_PSA_CRYPTO) |
| #define PK_MAX_EC_PUBLIC_KEY_SIZE PSA_EXPORT_PUBLIC_KEY_MAX_SIZE |
| #define PK_MAX_EC_KEY_PAIR_SIZE MBEDTLS_PSA_MAX_EC_KEY_PAIR_LENGTH |
| #else |
| #define PK_MAX_EC_PUBLIC_KEY_SIZE MBEDTLS_ECP_MAX_PT_LEN |
| #define PK_MAX_EC_KEY_PAIR_SIZE MBEDTLS_ECP_MAX_BYTES |
| #endif |
| |
| /****************************************************************************** |
| * Internal functions for RSA keys. |
| ******************************************************************************/ |
| #if defined(MBEDTLS_RSA_C) |
| static int pk_write_rsa_der(unsigned char **p, unsigned char *buf, |
| const mbedtls_pk_context *pk) |
| { |
| #if defined(MBEDTLS_USE_PSA_CRYPTO) |
| if (mbedtls_pk_get_type(pk) == MBEDTLS_PK_OPAQUE) { |
| uint8_t tmp[PSA_EXPORT_KEY_PAIR_MAX_SIZE]; |
| size_t len = 0, tmp_len = 0; |
| |
| if (psa_export_key(pk->priv_id, tmp, sizeof(tmp), &tmp_len) != PSA_SUCCESS) { |
| return MBEDTLS_ERR_PK_BAD_INPUT_DATA; |
| } |
| *p -= tmp_len; |
| memcpy(*p, tmp, tmp_len); |
| len += tmp_len; |
| mbedtls_platform_zeroize(tmp, sizeof(tmp)); |
| |
| return (int) len; |
| } |
| #endif /* MBEDTLS_USE_PSA_CRYPTO */ |
| return mbedtls_rsa_write_key(mbedtls_pk_rsa(*pk), buf, p); |
| } |
| #endif /* MBEDTLS_RSA_C */ |
| |
| /****************************************************************************** |
| * Internal functions for EC keys. |
| ******************************************************************************/ |
| #if defined(MBEDTLS_PK_HAVE_ECC_KEYS) |
| #if defined(MBEDTLS_PK_USE_PSA_EC_DATA) |
| static int pk_write_ec_pubkey(unsigned char **p, unsigned char *start, |
| const mbedtls_pk_context *pk) |
| { |
| size_t len = 0; |
| uint8_t buf[PK_MAX_EC_PUBLIC_KEY_SIZE]; |
| |
| if (mbedtls_pk_get_type(pk) == MBEDTLS_PK_OPAQUE) { |
| if (psa_export_public_key(pk->priv_id, buf, sizeof(buf), &len) != PSA_SUCCESS) { |
| return MBEDTLS_ERR_PK_BAD_INPUT_DATA; |
| } |
| } else { |
| len = pk->pub_raw_len; |
| memcpy(buf, pk->pub_raw, len); |
| } |
| |
| if (*p < start || (size_t) (*p - start) < len) { |
| return MBEDTLS_ERR_ASN1_BUF_TOO_SMALL; |
| } |
| |
| *p -= len; |
| memcpy(*p, buf, len); |
| |
| return (int) len; |
| } |
| #else /* MBEDTLS_PK_USE_PSA_EC_DATA */ |
| static int pk_write_ec_pubkey(unsigned char **p, unsigned char *start, |
| const mbedtls_pk_context *pk) |
| { |
| size_t len = 0; |
| unsigned char buf[PK_MAX_EC_PUBLIC_KEY_SIZE]; |
| mbedtls_ecp_keypair *ec = mbedtls_pk_ec(*pk); |
| int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; |
| |
| #if defined(MBEDTLS_USE_PSA_CRYPTO) |
| if (mbedtls_pk_get_type(pk) == MBEDTLS_PK_OPAQUE) { |
| if (psa_export_public_key(pk->priv_id, buf, sizeof(buf), &len) != PSA_SUCCESS) { |
| return MBEDTLS_ERR_PK_BAD_INPUT_DATA; |
| } |
| *p -= len; |
| memcpy(*p, buf, len); |
| return (int) len; |
| } else |
| #endif /* MBEDTLS_USE_PSA_CRYPTO */ |
| { |
| if ((ret = mbedtls_ecp_point_write_binary(&ec->grp, &ec->Q, |
| MBEDTLS_ECP_PF_UNCOMPRESSED, |
| &len, buf, sizeof(buf))) != 0) { |
| return ret; |
| } |
| } |
| |
| if (*p < start || (size_t) (*p - start) < len) { |
| return MBEDTLS_ERR_ASN1_BUF_TOO_SMALL; |
| } |
| |
| *p -= len; |
| memcpy(*p, buf, len); |
| |
| return (int) len; |
| } |
| #endif /* MBEDTLS_PK_USE_PSA_EC_DATA */ |
| |
| /* |
| * privateKey OCTET STRING -- always of length ceil(log2(n)/8) |
| */ |
| #if defined(MBEDTLS_PK_USE_PSA_EC_DATA) |
| static int pk_write_ec_private(unsigned char **p, unsigned char *start, |
| const mbedtls_pk_context *pk) |
| { |
| size_t byte_length; |
| int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; |
| unsigned char tmp[PK_MAX_EC_KEY_PAIR_SIZE]; |
| psa_status_t status; |
| |
| if (mbedtls_pk_get_type(pk) == MBEDTLS_PK_OPAQUE) { |
| status = psa_export_key(pk->priv_id, tmp, sizeof(tmp), &byte_length); |
| if (status != PSA_SUCCESS) { |
| ret = PSA_PK_ECDSA_TO_MBEDTLS_ERR(status); |
| return ret; |
| } |
| } else { |
| status = psa_export_key(pk->priv_id, tmp, sizeof(tmp), &byte_length); |
| if (status != PSA_SUCCESS) { |
| ret = PSA_PK_ECDSA_TO_MBEDTLS_ERR(status); |
| goto exit; |
| } |
| } |
| |
| ret = mbedtls_asn1_write_octet_string(p, start, tmp, byte_length); |
| exit: |
| mbedtls_platform_zeroize(tmp, sizeof(tmp)); |
| return ret; |
| } |
| #else /* MBEDTLS_PK_USE_PSA_EC_DATA */ |
| static int pk_write_ec_private(unsigned char **p, unsigned char *start, |
| const mbedtls_pk_context *pk) |
| { |
| size_t byte_length; |
| int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; |
| unsigned char tmp[PK_MAX_EC_KEY_PAIR_SIZE]; |
| |
| #if defined(MBEDTLS_USE_PSA_CRYPTO) |
| psa_status_t status; |
| if (mbedtls_pk_get_type(pk) == MBEDTLS_PK_OPAQUE) { |
| status = psa_export_key(pk->priv_id, tmp, sizeof(tmp), &byte_length); |
| if (status != PSA_SUCCESS) { |
| ret = PSA_PK_ECDSA_TO_MBEDTLS_ERR(status); |
| return ret; |
| } |
| } else |
| #endif /* MBEDTLS_USE_PSA_CRYPTO */ |
| { |
| mbedtls_ecp_keypair *ec = mbedtls_pk_ec_rw(*pk); |
| byte_length = (ec->grp.pbits + 7) / 8; |
| |
| ret = mbedtls_ecp_write_key_ext(ec, &byte_length, tmp, sizeof(tmp)); |
| if (ret != 0) { |
| goto exit; |
| } |
| } |
| ret = mbedtls_asn1_write_octet_string(p, start, tmp, byte_length); |
| exit: |
| mbedtls_platform_zeroize(tmp, sizeof(tmp)); |
| return ret; |
| } |
| #endif /* MBEDTLS_PK_USE_PSA_EC_DATA */ |
| |
| /* |
| * ECParameters ::= CHOICE { |
| * namedCurve OBJECT IDENTIFIER |
| * } |
| */ |
| static int pk_write_ec_param(unsigned char **p, unsigned char *start, |
| mbedtls_ecp_group_id grp_id) |
| { |
| int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; |
| size_t len = 0; |
| const char *oid; |
| size_t oid_len; |
| |
| if ((ret = mbedtls_oid_get_oid_by_ec_grp(grp_id, &oid, &oid_len)) != 0) { |
| return ret; |
| } |
| |
| MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_oid(p, start, oid, oid_len)); |
| |
| return (int) len; |
| } |
| |
| #if defined(MBEDTLS_PK_HAVE_RFC8410_CURVES) |
| /* |
| * RFC8410 section 7 |
| * |
| * OneAsymmetricKey ::= SEQUENCE { |
| * version Version, |
| * privateKeyAlgorithm PrivateKeyAlgorithmIdentifier, |
| * privateKey PrivateKey, |
| * attributes [0] IMPLICIT Attributes OPTIONAL, |
| * ..., |
| * [[2: publicKey [1] IMPLICIT PublicKey OPTIONAL ]], |
| * ... |
| * } |
| * ... |
| * CurvePrivateKey ::= OCTET STRING |
| */ |
| static int pk_write_ec_rfc8410_der(unsigned char **p, unsigned char *buf, |
| const mbedtls_pk_context *pk) |
| { |
| int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; |
| size_t len = 0; |
| size_t oid_len = 0; |
| const char *oid; |
| mbedtls_ecp_group_id grp_id; |
| |
| /* privateKey */ |
| MBEDTLS_ASN1_CHK_ADD(len, pk_write_ec_private(p, buf, pk)); |
| MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(p, buf, len)); |
| MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_tag(p, buf, MBEDTLS_ASN1_OCTET_STRING)); |
| |
| grp_id = mbedtls_pk_get_ec_group_id(pk); |
| /* privateKeyAlgorithm */ |
| if ((ret = mbedtls_oid_get_oid_by_ec_grp_algid(grp_id, &oid, &oid_len)) != 0) { |
| return ret; |
| } |
| MBEDTLS_ASN1_CHK_ADD(len, |
| mbedtls_asn1_write_algorithm_identifier_ext(p, buf, oid, oid_len, 0, 0)); |
| |
| /* version */ |
| MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_int(p, buf, 0)); |
| |
| MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(p, buf, len)); |
| MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_tag(p, buf, MBEDTLS_ASN1_CONSTRUCTED | |
| MBEDTLS_ASN1_SEQUENCE)); |
| |
| return (int) len; |
| } |
| #endif /* MBEDTLS_PK_HAVE_RFC8410_CURVES */ |
| |
| /* |
| * RFC 5915, or SEC1 Appendix C.4 |
| * |
| * ECPrivateKey ::= SEQUENCE { |
| * version INTEGER { ecPrivkeyVer1(1) } (ecPrivkeyVer1), |
| * privateKey OCTET STRING, |
| * parameters [0] ECParameters {{ NamedCurve }} OPTIONAL, |
| * publicKey [1] BIT STRING OPTIONAL |
| * } |
| */ |
| static int pk_write_ec_der(unsigned char **p, unsigned char *buf, |
| const mbedtls_pk_context *pk) |
| { |
| size_t len = 0; |
| int ret; |
| size_t pub_len = 0, par_len = 0; |
| mbedtls_ecp_group_id grp_id; |
| |
| /* publicKey */ |
| MBEDTLS_ASN1_CHK_ADD(pub_len, pk_write_ec_pubkey(p, buf, pk)); |
| |
| if (*p - buf < 1) { |
| return MBEDTLS_ERR_ASN1_BUF_TOO_SMALL; |
| } |
| (*p)--; |
| **p = 0; |
| pub_len += 1; |
| |
| MBEDTLS_ASN1_CHK_ADD(pub_len, mbedtls_asn1_write_len(p, buf, pub_len)); |
| MBEDTLS_ASN1_CHK_ADD(pub_len, mbedtls_asn1_write_tag(p, buf, MBEDTLS_ASN1_BIT_STRING)); |
| |
| MBEDTLS_ASN1_CHK_ADD(pub_len, mbedtls_asn1_write_len(p, buf, pub_len)); |
| MBEDTLS_ASN1_CHK_ADD(pub_len, mbedtls_asn1_write_tag(p, buf, |
| MBEDTLS_ASN1_CONTEXT_SPECIFIC | |
| MBEDTLS_ASN1_CONSTRUCTED | 1)); |
| len += pub_len; |
| |
| /* parameters */ |
| grp_id = mbedtls_pk_get_ec_group_id(pk); |
| MBEDTLS_ASN1_CHK_ADD(par_len, pk_write_ec_param(p, buf, grp_id)); |
| MBEDTLS_ASN1_CHK_ADD(par_len, mbedtls_asn1_write_len(p, buf, par_len)); |
| MBEDTLS_ASN1_CHK_ADD(par_len, mbedtls_asn1_write_tag(p, buf, |
| MBEDTLS_ASN1_CONTEXT_SPECIFIC | |
| MBEDTLS_ASN1_CONSTRUCTED | 0)); |
| len += par_len; |
| |
| /* privateKey */ |
| MBEDTLS_ASN1_CHK_ADD(len, pk_write_ec_private(p, buf, pk)); |
| |
| /* version */ |
| MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_int(p, buf, 1)); |
| |
| MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(p, buf, len)); |
| MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_tag(p, buf, MBEDTLS_ASN1_CONSTRUCTED | |
| MBEDTLS_ASN1_SEQUENCE)); |
| |
| return (int) len; |
| } |
| #endif /* MBEDTLS_PK_HAVE_ECC_KEYS */ |
| |
| /****************************************************************************** |
| * Internal functions for Opaque keys. |
| ******************************************************************************/ |
| #if defined(MBEDTLS_USE_PSA_CRYPTO) |
| static int pk_write_opaque_pubkey(unsigned char **p, unsigned char *start, |
| const mbedtls_pk_context *pk) |
| { |
| size_t buffer_size; |
| size_t len = 0; |
| |
| if (*p < start) { |
| return MBEDTLS_ERR_PK_BAD_INPUT_DATA; |
| } |
| |
| buffer_size = (size_t) (*p - start); |
| if (psa_export_public_key(pk->priv_id, start, buffer_size, |
| &len) != PSA_SUCCESS) { |
| return MBEDTLS_ERR_PK_BAD_INPUT_DATA; |
| } |
| |
| *p -= len; |
| memmove(*p, start, len); |
| |
| return (int) len; |
| } |
| #endif /* MBEDTLS_USE_PSA_CRYPTO */ |
| |
| /****************************************************************************** |
| * Generic helpers |
| ******************************************************************************/ |
| |
| /* Extend the public mbedtls_pk_get_type() by getting key type also in case of |
| * opaque keys. */ |
| static mbedtls_pk_type_t pk_get_type_ext(const mbedtls_pk_context *pk) |
| { |
| mbedtls_pk_type_t pk_type = mbedtls_pk_get_type(pk); |
| |
| #if defined(MBEDTLS_USE_PSA_CRYPTO) |
| if (pk_type == MBEDTLS_PK_OPAQUE) { |
| psa_key_attributes_t opaque_attrs = PSA_KEY_ATTRIBUTES_INIT; |
| psa_key_type_t opaque_key_type; |
| |
| if (psa_get_key_attributes(pk->priv_id, &opaque_attrs) != PSA_SUCCESS) { |
| return MBEDTLS_PK_NONE; |
| } |
| opaque_key_type = psa_get_key_type(&opaque_attrs); |
| psa_reset_key_attributes(&opaque_attrs); |
| |
| if (PSA_KEY_TYPE_IS_ECC(opaque_key_type)) { |
| return MBEDTLS_PK_ECKEY; |
| } else if (PSA_KEY_TYPE_IS_RSA(opaque_key_type)) { |
| return MBEDTLS_PK_RSA; |
| } else { |
| return MBEDTLS_PK_NONE; |
| } |
| } else |
| #endif |
| return pk_type; |
| } |
| |
| /****************************************************************************** |
| * Public functions for writing private/public DER keys. |
| ******************************************************************************/ |
| int mbedtls_pk_write_pubkey(unsigned char **p, unsigned char *start, |
| const mbedtls_pk_context *key) |
| { |
| int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; |
| size_t len = 0; |
| |
| #if defined(MBEDTLS_RSA_C) |
| if (mbedtls_pk_get_type(key) == MBEDTLS_PK_RSA) { |
| MBEDTLS_ASN1_CHK_ADD(len, mbedtls_rsa_write_pubkey(mbedtls_pk_rsa(*key), start, p)); |
| } else |
| #endif |
| #if defined(MBEDTLS_PK_HAVE_ECC_KEYS) |
| if (mbedtls_pk_get_type(key) == MBEDTLS_PK_ECKEY) { |
| MBEDTLS_ASN1_CHK_ADD(len, pk_write_ec_pubkey(p, start, key)); |
| } else |
| #endif |
| #if defined(MBEDTLS_USE_PSA_CRYPTO) |
| if (mbedtls_pk_get_type(key) == MBEDTLS_PK_OPAQUE) { |
| MBEDTLS_ASN1_CHK_ADD(len, pk_write_opaque_pubkey(p, start, key)); |
| } else |
| #endif /* MBEDTLS_USE_PSA_CRYPTO */ |
| return MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE; |
| |
| return (int) len; |
| } |
| |
| int mbedtls_pk_write_pubkey_der(const mbedtls_pk_context *key, unsigned char *buf, size_t size) |
| { |
| int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; |
| unsigned char *c; |
| int has_par = 1; |
| size_t len = 0, par_len = 0, oid_len = 0; |
| mbedtls_pk_type_t pk_type; |
| const char *oid = NULL; |
| |
| if (size == 0) { |
| return MBEDTLS_ERR_ASN1_BUF_TOO_SMALL; |
| } |
| |
| c = buf + size; |
| |
| MBEDTLS_ASN1_CHK_ADD(len, mbedtls_pk_write_pubkey(&c, buf, key)); |
| |
| if (c - buf < 1) { |
| return MBEDTLS_ERR_ASN1_BUF_TOO_SMALL; |
| } |
| |
| /* |
| * SubjectPublicKeyInfo ::= SEQUENCE { |
| * algorithm AlgorithmIdentifier, |
| * subjectPublicKey BIT STRING } |
| */ |
| *--c = 0; |
| len += 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_BIT_STRING)); |
| |
| pk_type = pk_get_type_ext(key); |
| |
| #if defined(MBEDTLS_PK_HAVE_ECC_KEYS) |
| if (pk_get_type_ext(key) == MBEDTLS_PK_ECKEY) { |
| mbedtls_ecp_group_id ec_grp_id = mbedtls_pk_get_ec_group_id(key); |
| if (MBEDTLS_PK_IS_RFC8410_GROUP_ID(ec_grp_id)) { |
| ret = mbedtls_oid_get_oid_by_ec_grp_algid(ec_grp_id, &oid, &oid_len); |
| if (ret != 0) { |
| return ret; |
| } |
| has_par = 0; |
| } else { |
| MBEDTLS_ASN1_CHK_ADD(par_len, pk_write_ec_param(&c, buf, ec_grp_id)); |
| } |
| } |
| #endif /* MBEDTLS_PK_HAVE_ECC_KEYS */ |
| |
| /* At this point oid_len is not null only for EC Montgomery keys. */ |
| if (oid_len == 0) { |
| ret = mbedtls_oid_get_oid_by_pk_alg(pk_type, &oid, &oid_len); |
| if (ret != 0) { |
| return ret; |
| } |
| } |
| |
| MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_algorithm_identifier_ext(&c, buf, oid, oid_len, |
| par_len, has_par)); |
| |
| 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; |
| } |
| |
| int mbedtls_pk_write_key_der(const mbedtls_pk_context *key, unsigned char *buf, size_t size) |
| { |
| unsigned char *c; |
| |
| if (size == 0) { |
| return MBEDTLS_ERR_ASN1_BUF_TOO_SMALL; |
| } |
| |
| c = buf + size; |
| |
| #if defined(MBEDTLS_RSA_C) |
| if (pk_get_type_ext(key) == MBEDTLS_PK_RSA) { |
| return pk_write_rsa_der(&c, buf, key); |
| } else |
| #endif /* MBEDTLS_RSA_C */ |
| #if defined(MBEDTLS_PK_HAVE_ECC_KEYS) |
| if (pk_get_type_ext(key) == MBEDTLS_PK_ECKEY) { |
| #if defined(MBEDTLS_PK_HAVE_RFC8410_CURVES) |
| if (mbedtls_pk_is_rfc8410(key)) { |
| return pk_write_ec_rfc8410_der(&c, buf, key); |
| } |
| #endif /* MBEDTLS_PK_HAVE_RFC8410_CURVES */ |
| return pk_write_ec_der(&c, buf, key); |
| } else |
| #endif /* MBEDTLS_PK_HAVE_ECC_KEYS */ |
| return MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE; |
| } |
| |
| /****************************************************************************** |
| * Public functions for wrinting private/public PEM keys. |
| ******************************************************************************/ |
| #if defined(MBEDTLS_PEM_WRITE_C) |
| |
| #define PUB_DER_MAX_BYTES \ |
| (MBEDTLS_PK_RSA_PUB_DER_MAX_BYTES > MBEDTLS_PK_ECP_PUB_DER_MAX_BYTES ? \ |
| MBEDTLS_PK_RSA_PUB_DER_MAX_BYTES : MBEDTLS_PK_ECP_PUB_DER_MAX_BYTES) |
| #define PRV_DER_MAX_BYTES \ |
| (MBEDTLS_PK_RSA_PRV_DER_MAX_BYTES > MBEDTLS_PK_ECP_PRV_DER_MAX_BYTES ? \ |
| MBEDTLS_PK_RSA_PRV_DER_MAX_BYTES : MBEDTLS_PK_ECP_PRV_DER_MAX_BYTES) |
| |
| int mbedtls_pk_write_pubkey_pem(const mbedtls_pk_context *key, unsigned char *buf, size_t size) |
| { |
| int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; |
| unsigned char *output_buf = NULL; |
| output_buf = mbedtls_calloc(1, PUB_DER_MAX_BYTES); |
| if (output_buf == NULL) { |
| return MBEDTLS_ERR_PK_ALLOC_FAILED; |
| } |
| size_t olen = 0; |
| |
| if ((ret = mbedtls_pk_write_pubkey_der(key, output_buf, |
| PUB_DER_MAX_BYTES)) < 0) { |
| goto cleanup; |
| } |
| |
| if ((ret = mbedtls_pem_write_buffer(PEM_BEGIN_PUBLIC_KEY "\n", PEM_END_PUBLIC_KEY "\n", |
| output_buf + PUB_DER_MAX_BYTES - ret, |
| ret, buf, size, &olen)) != 0) { |
| goto cleanup; |
| } |
| |
| ret = 0; |
| cleanup: |
| mbedtls_free(output_buf); |
| return ret; |
| } |
| |
| int mbedtls_pk_write_key_pem(const mbedtls_pk_context *key, unsigned char *buf, size_t size) |
| { |
| int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; |
| unsigned char *output_buf = NULL; |
| output_buf = mbedtls_calloc(1, PRV_DER_MAX_BYTES); |
| if (output_buf == NULL) { |
| return MBEDTLS_ERR_PK_ALLOC_FAILED; |
| } |
| const char *begin, *end; |
| size_t olen = 0; |
| |
| if ((ret = mbedtls_pk_write_key_der(key, output_buf, PRV_DER_MAX_BYTES)) < 0) { |
| goto cleanup; |
| } |
| |
| #if defined(MBEDTLS_RSA_C) |
| if (pk_get_type_ext(key) == MBEDTLS_PK_RSA) { |
| begin = PEM_BEGIN_PRIVATE_KEY_RSA "\n"; |
| end = PEM_END_PRIVATE_KEY_RSA "\n"; |
| } else |
| #endif |
| #if defined(MBEDTLS_PK_HAVE_ECC_KEYS) |
| if (pk_get_type_ext(key) == MBEDTLS_PK_ECKEY) { |
| if (mbedtls_pk_is_rfc8410(key)) { |
| begin = PEM_BEGIN_PRIVATE_KEY_PKCS8 "\n"; |
| end = PEM_END_PRIVATE_KEY_PKCS8 "\n"; |
| } else { |
| begin = PEM_BEGIN_PRIVATE_KEY_EC "\n"; |
| end = PEM_END_PRIVATE_KEY_EC "\n"; |
| } |
| } else |
| #endif /* MBEDTLS_PK_HAVE_ECC_KEYS */ |
| { |
| ret = MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE; |
| goto cleanup; |
| } |
| |
| if ((ret = mbedtls_pem_write_buffer(begin, end, |
| output_buf + PRV_DER_MAX_BYTES - ret, |
| ret, buf, size, &olen)) != 0) { |
| goto cleanup; |
| } |
| |
| ret = 0; |
| cleanup: |
| mbedtls_zeroize_and_free(output_buf, PRV_DER_MAX_BYTES); |
| return ret; |
| } |
| #endif /* MBEDTLS_PEM_WRITE_C */ |
| |
| #endif /* MBEDTLS_PK_WRITE_C */ |
