Squashed 'lib/mbedtls/external/mbedtls/' content from commit 2ca6c285a0dd
git-subtree-dir: lib/mbedtls/external/mbedtls
git-subtree-split: 2ca6c285a0dd3f33982dd57299012dacab1ff206
diff --git a/library/pkwrite.c b/library/pkwrite.c
new file mode 100644
index 0000000..5e009c5
--- /dev/null
+++ b/library/pkwrite.c
@@ -0,0 +1,621 @@
+/*
+ * 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 */