Squashed 'lib/mbedtls/external/mbedtls/' content from commit 2ca6c285a0dd

git-subtree-dir: lib/mbedtls/external/mbedtls
git-subtree-split: 2ca6c285a0dd3f33982dd57299012dacab1ff206

1 files changed, 1392 insertions, 0 deletions

diff --git a/library/pkparse.c b/library/pkparse.c
new file mode 100644
index 00000000000..4f6ee139862
--- /dev/null
+++ b/library/pkparse.c
@@ -0,0 +1,1392 @@
+/*
+ *  Public Key layer for parsing 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_PARSE_C)
+
+#include "mbedtls/pk.h"
+#include "mbedtls/asn1.h"
+#include "mbedtls/oid.h"
+#include "mbedtls/platform_util.h"
+#include "mbedtls/platform.h"
+#include "mbedtls/error.h"
+#include "mbedtls/ecp.h"
+#include "pk_internal.h"
+
+#include <string.h>
+
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+#include "mbedtls/psa_util.h"
+#include "psa/crypto.h"
+#endif
+
+/* Key types */
+#if defined(MBEDTLS_RSA_C)
+#include "mbedtls/rsa.h"
+#include "rsa_internal.h"
+#endif
+
+/* Extended formats */
+#if defined(MBEDTLS_PEM_PARSE_C)
+#include "mbedtls/pem.h"
+#endif
+#if defined(MBEDTLS_PKCS5_C)
+#include "mbedtls/pkcs5.h"
+#endif
+#if defined(MBEDTLS_PKCS12_C)
+#include "mbedtls/pkcs12.h"
+#endif
+
+#if defined(MBEDTLS_PK_HAVE_ECC_KEYS)
+
+/***********************************************************************
+ *
+ *      Low-level ECC parsing: optional support for SpecifiedECDomain
+ *
+ * There are two functions here that are used by the rest of the code:
+ * - pk_ecc_tag_is_speficied_ec_domain()
+ * - pk_ecc_group_id_from_specified()
+ *
+ * All the other functions are internal to this section.
+ *
+ * The two "public" functions have a dummy variant provided
+ * in configs without MBEDTLS_PK_PARSE_EC_EXTENDED. This acts as an
+ * abstraction layer for this macro, which should not appear outside
+ * this section.
+ *
+ **********************************************************************/
+
+#if !defined(MBEDTLS_PK_PARSE_EC_EXTENDED)
+/* See the "real" version for documentation */
+static int pk_ecc_tag_is_specified_ec_domain(int tag)
+{
+    (void) tag;
+    return 0;
+}
+
+/* See the "real" version for documentation */
+static int pk_ecc_group_id_from_specified(const mbedtls_asn1_buf *params,
+                                          mbedtls_ecp_group_id *grp_id)
+{
+    (void) params;
+    (void) grp_id;
+    return MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE;
+}
+#else /* MBEDTLS_PK_PARSE_EC_EXTENDED */
+/*
+ * Tell if the passed tag might be the start of SpecifiedECDomain
+ * (that is, a sequence).
+ */
+static int pk_ecc_tag_is_specified_ec_domain(int tag)
+{
+    return tag == (MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE);
+}
+
+/*
+ * Parse a SpecifiedECDomain (SEC 1 C.2) and (mostly) fill the group with it.
+ * WARNING: the resulting group should only be used with
+ * pk_ecc_group_id_from_specified(), since its base point may not be set correctly
+ * if it was encoded compressed.
+ *
+ *  SpecifiedECDomain ::= SEQUENCE {
+ *      version SpecifiedECDomainVersion(ecdpVer1 | ecdpVer2 | ecdpVer3, ...),
+ *      fieldID FieldID {{FieldTypes}},
+ *      curve Curve,
+ *      base ECPoint,
+ *      order INTEGER,
+ *      cofactor INTEGER OPTIONAL,
+ *      hash HashAlgorithm OPTIONAL,
+ *      ...
+ *  }
+ *
+ * We only support prime-field as field type, and ignore hash and cofactor.
+ */
+static int pk_group_from_specified(const mbedtls_asn1_buf *params, mbedtls_ecp_group *grp)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    unsigned char *p = params->p;
+    const unsigned char *const end = params->p + params->len;
+    const unsigned char *end_field, *end_curve;
+    size_t len;
+    int ver;
+
+    /* SpecifiedECDomainVersion ::= INTEGER { 1, 2, 3 } */
+    if ((ret = mbedtls_asn1_get_int(&p, end, &ver)) != 0) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
+    }
+
+    if (ver < 1 || ver > 3) {
+        return MBEDTLS_ERR_PK_KEY_INVALID_FORMAT;
+    }
+
+    /*
+     * FieldID { FIELD-ID:IOSet } ::= SEQUENCE { -- Finite field
+     *       fieldType FIELD-ID.&id({IOSet}),
+     *       parameters FIELD-ID.&Type({IOSet}{@fieldType})
+     * }
+     */
+    if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
+                                    MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
+        return ret;
+    }
+
+    end_field = p + len;
+
+    /*
+     * FIELD-ID ::= TYPE-IDENTIFIER
+     * FieldTypes FIELD-ID ::= {
+     *       { Prime-p IDENTIFIED BY prime-field } |
+     *       { Characteristic-two IDENTIFIED BY characteristic-two-field }
+     * }
+     * prime-field OBJECT IDENTIFIER ::= { id-fieldType 1 }
+     */
+    if ((ret = mbedtls_asn1_get_tag(&p, end_field, &len, MBEDTLS_ASN1_OID)) != 0) {
+        return ret;
+    }
+
+    if (len != MBEDTLS_OID_SIZE(MBEDTLS_OID_ANSI_X9_62_PRIME_FIELD) ||
+        memcmp(p, MBEDTLS_OID_ANSI_X9_62_PRIME_FIELD, len) != 0) {
+        return MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE;
+    }
+
+    p += len;
+
+    /* Prime-p ::= INTEGER -- Field of size p. */
+    if ((ret = mbedtls_asn1_get_mpi(&p, end_field, &grp->P)) != 0) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
+    }
+
+    grp->pbits = mbedtls_mpi_bitlen(&grp->P);
+
+    if (p != end_field) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT,
+                                 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
+    }
+
+    /*
+     * Curve ::= SEQUENCE {
+     *       a FieldElement,
+     *       b FieldElement,
+     *       seed BIT STRING OPTIONAL
+     *       -- Shall be present if used in SpecifiedECDomain
+     *       -- with version equal to ecdpVer2 or ecdpVer3
+     * }
+     */
+    if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
+                                    MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
+        return ret;
+    }
+
+    end_curve = p + len;
+
+    /*
+     * FieldElement ::= OCTET STRING
+     * containing an integer in the case of a prime field
+     */
+    if ((ret = mbedtls_asn1_get_tag(&p, end_curve, &len, MBEDTLS_ASN1_OCTET_STRING)) != 0 ||
+        (ret = mbedtls_mpi_read_binary(&grp->A, p, len)) != 0) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
+    }
+
+    p += len;
+
+    if ((ret = mbedtls_asn1_get_tag(&p, end_curve, &len, MBEDTLS_ASN1_OCTET_STRING)) != 0 ||
+        (ret = mbedtls_mpi_read_binary(&grp->B, p, len)) != 0) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
+    }
+
+    p += len;
+
+    /* Ignore seed BIT STRING OPTIONAL */
+    if ((ret = mbedtls_asn1_get_tag(&p, end_curve, &len, MBEDTLS_ASN1_BIT_STRING)) == 0) {
+        p += len;
+    }
+
+    if (p != end_curve) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT,
+                                 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
+    }
+
+    /*
+     * ECPoint ::= OCTET STRING
+     */
+    if ((ret = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_OCTET_STRING)) != 0) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
+    }
+
+    if ((ret = mbedtls_ecp_point_read_binary(grp, &grp->G,
+                                             (const unsigned char *) p, len)) != 0) {
+        /*
+         * If we can't read the point because it's compressed, cheat by
+         * reading only the X coordinate and the parity bit of Y.
+         */
+        if (ret != MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE ||
+            (p[0] != 0x02 && p[0] != 0x03) ||
+            len != mbedtls_mpi_size(&grp->P) + 1 ||
+            mbedtls_mpi_read_binary(&grp->G.X, p + 1, len - 1) != 0 ||
+            mbedtls_mpi_lset(&grp->G.Y, p[0] - 2) != 0 ||
+            mbedtls_mpi_lset(&grp->G.Z, 1) != 0) {
+            return MBEDTLS_ERR_PK_KEY_INVALID_FORMAT;
+        }
+    }
+
+    p += len;
+
+    /*
+     * order INTEGER
+     */
+    if ((ret = mbedtls_asn1_get_mpi(&p, end, &grp->N)) != 0) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
+    }
+
+    grp->nbits = mbedtls_mpi_bitlen(&grp->N);
+
+    /*
+     * Allow optional elements by purposefully not enforcing p == end here.
+     */
+
+    return 0;
+}
+
+/*
+ * Find the group id associated with an (almost filled) group as generated by
+ * pk_group_from_specified(), or return an error if unknown.
+ */
+static int pk_group_id_from_group(const mbedtls_ecp_group *grp, mbedtls_ecp_group_id *grp_id)
+{
+    int ret = 0;
+    mbedtls_ecp_group ref;
+    const mbedtls_ecp_group_id *id;
+
+    mbedtls_ecp_group_init(&ref);
+
+    for (id = mbedtls_ecp_grp_id_list(); *id != MBEDTLS_ECP_DP_NONE; id++) {
+        /* Load the group associated to that id */
+        mbedtls_ecp_group_free(&ref);
+        MBEDTLS_MPI_CHK(mbedtls_ecp_group_load(&ref, *id));
+
+        /* Compare to the group we were given, starting with easy tests */
+        if (grp->pbits == ref.pbits && grp->nbits == ref.nbits &&
+            mbedtls_mpi_cmp_mpi(&grp->P, &ref.P) == 0 &&
+            mbedtls_mpi_cmp_mpi(&grp->A, &ref.A) == 0 &&
+            mbedtls_mpi_cmp_mpi(&grp->B, &ref.B) == 0 &&
+            mbedtls_mpi_cmp_mpi(&grp->N, &ref.N) == 0 &&
+            mbedtls_mpi_cmp_mpi(&grp->G.X, &ref.G.X) == 0 &&
+            mbedtls_mpi_cmp_mpi(&grp->G.Z, &ref.G.Z) == 0 &&
+            /* For Y we may only know the parity bit, so compare only that */
+            mbedtls_mpi_get_bit(&grp->G.Y, 0) == mbedtls_mpi_get_bit(&ref.G.Y, 0)) {
+            break;
+        }
+    }
+
+cleanup:
+    mbedtls_ecp_group_free(&ref);
+
+    *grp_id = *id;
+
+    if (ret == 0 && *id == MBEDTLS_ECP_DP_NONE) {
+        ret = MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE;
+    }
+
+    return ret;
+}
+
+/*
+ * Parse a SpecifiedECDomain (SEC 1 C.2) and find the associated group ID
+ */
+static int pk_ecc_group_id_from_specified(const mbedtls_asn1_buf *params,
+                                          mbedtls_ecp_group_id *grp_id)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    mbedtls_ecp_group grp;
+
+    mbedtls_ecp_group_init(&grp);
+
+    if ((ret = pk_group_from_specified(params, &grp)) != 0) {
+        goto cleanup;
+    }
+
+    ret = pk_group_id_from_group(&grp, grp_id);
+
+cleanup:
+    /* The API respecting lifecycle for mbedtls_ecp_group struct is
+     * _init(), _load() and _free(). In pk_ecc_group_id_from_specified() the
+     * temporary grp breaks that flow and it's members are populated
+     * by pk_group_id_from_group(). As such mbedtls_ecp_group_free()
+     * which is assuming a group populated by _setup() may not clean-up
+     * properly -> Manually free it's members.
+     */
+    mbedtls_mpi_free(&grp.N);
+    mbedtls_mpi_free(&grp.P);
+    mbedtls_mpi_free(&grp.A);
+    mbedtls_mpi_free(&grp.B);
+    mbedtls_ecp_point_free(&grp.G);
+
+    return ret;
+}
+#endif /* MBEDTLS_PK_PARSE_EC_EXTENDED */
+
+/***********************************************************************
+ *
+ * Unsorted (yet!) from this point on until the next section header
+ *
+ **********************************************************************/
+
+/* Minimally parse an ECParameters buffer to and mbedtls_asn1_buf
+ *
+ * ECParameters ::= CHOICE {
+ *   namedCurve         OBJECT IDENTIFIER
+ *   specifiedCurve     SpecifiedECDomain -- = SEQUENCE { ... }
+ *   -- implicitCurve   NULL
+ * }
+ */
+static int pk_get_ecparams(unsigned char **p, const unsigned char *end,
+                           mbedtls_asn1_buf *params)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+
+    if (end - *p < 1) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT,
+                                 MBEDTLS_ERR_ASN1_OUT_OF_DATA);
+    }
+
+    /* Acceptable tags: OID for namedCurve, or specifiedECDomain */
+    params->tag = **p;
+    if (params->tag != MBEDTLS_ASN1_OID &&
+        !pk_ecc_tag_is_specified_ec_domain(params->tag)) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT,
+                                 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG);
+    }
+
+    if ((ret = mbedtls_asn1_get_tag(p, end, &params->len, params->tag)) != 0) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
+    }
+
+    params->p = *p;
+    *p += params->len;
+
+    if (*p != end) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT,
+                                 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
+    }
+
+    return 0;
+}
+
+/*
+ * Use EC parameters to initialise an EC group
+ *
+ * ECParameters ::= CHOICE {
+ *   namedCurve         OBJECT IDENTIFIER
+ *   specifiedCurve     SpecifiedECDomain -- = SEQUENCE { ... }
+ *   -- implicitCurve   NULL
+ */
+static int pk_use_ecparams(const mbedtls_asn1_buf *params, mbedtls_pk_context *pk)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    mbedtls_ecp_group_id grp_id;
+
+    if (params->tag == MBEDTLS_ASN1_OID) {
+        if (mbedtls_oid_get_ec_grp(params, &grp_id) != 0) {
+            return MBEDTLS_ERR_PK_UNKNOWN_NAMED_CURVE;
+        }
+    } else {
+        ret = pk_ecc_group_id_from_specified(params, &grp_id);
+        if (ret != 0) {
+            return ret;
+        }
+    }
+
+    return mbedtls_pk_ecc_set_group(pk, grp_id);
+}
+
+#if defined(MBEDTLS_PK_HAVE_RFC8410_CURVES)
+
+/*
+ * Load an RFC8410 EC key, which doesn't have any parameters
+ */
+static int pk_use_ecparams_rfc8410(const mbedtls_asn1_buf *params,
+                                   mbedtls_ecp_group_id grp_id,
+                                   mbedtls_pk_context *pk)
+{
+    if (params->tag != 0 || params->len != 0) {
+        return MBEDTLS_ERR_PK_KEY_INVALID_FORMAT;
+    }
+
+    return mbedtls_pk_ecc_set_group(pk, grp_id);
+}
+
+/*
+ * Parse an RFC 8410 encoded private EC key
+ *
+ * CurvePrivateKey ::= OCTET STRING
+ */
+static int pk_parse_key_rfc8410_der(mbedtls_pk_context *pk,
+                                    unsigned char *key, size_t keylen, const unsigned char *end,
+                                    int (*f_rng)(void *, unsigned char *, size_t), void *p_rng)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    size_t len;
+
+    if ((ret = mbedtls_asn1_get_tag(&key, (key + keylen), &len, MBEDTLS_ASN1_OCTET_STRING)) != 0) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
+    }
+
+    if (key + len != end) {
+        return MBEDTLS_ERR_PK_KEY_INVALID_FORMAT;
+    }
+
+    /*
+     * Load the private key
+     */
+    ret = mbedtls_pk_ecc_set_key(pk, key, len);
+    if (ret != 0) {
+        return ret;
+    }
+
+    /* pk_parse_key_pkcs8_unencrypted_der() only supports version 1 PKCS8 keys,
+     * which never contain a public key. As such, derive the public key
+     * unconditionally. */
+    if ((ret = mbedtls_pk_ecc_set_pubkey_from_prv(pk, key, len, f_rng, p_rng)) != 0) {
+        return ret;
+    }
+
+    return 0;
+}
+#endif /* MBEDTLS_PK_HAVE_RFC8410_CURVES */
+
+#endif /* MBEDTLS_PK_HAVE_ECC_KEYS */
+
+/* Get a PK algorithm identifier
+ *
+ *  AlgorithmIdentifier  ::=  SEQUENCE  {
+ *       algorithm               OBJECT IDENTIFIER,
+ *       parameters              ANY DEFINED BY algorithm OPTIONAL  }
+ */
+static int pk_get_pk_alg(unsigned char **p,
+                         const unsigned char *end,
+                         mbedtls_pk_type_t *pk_alg, mbedtls_asn1_buf *params,
+                         mbedtls_ecp_group_id *ec_grp_id)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    mbedtls_asn1_buf alg_oid;
+
+    memset(params, 0, sizeof(mbedtls_asn1_buf));
+
+    if ((ret = mbedtls_asn1_get_alg(p, end, &alg_oid, params)) != 0) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_INVALID_ALG, ret);
+    }
+
+    ret = mbedtls_oid_get_pk_alg(&alg_oid, pk_alg);
+#if defined(MBEDTLS_PK_HAVE_ECC_KEYS)
+    if (ret == MBEDTLS_ERR_OID_NOT_FOUND) {
+        ret = mbedtls_oid_get_ec_grp_algid(&alg_oid, ec_grp_id);
+        if (ret == 0) {
+            *pk_alg = MBEDTLS_PK_ECKEY;
+        }
+    }
+#else
+    (void) ec_grp_id;
+#endif
+    if (ret != 0) {
+        return MBEDTLS_ERR_PK_UNKNOWN_PK_ALG;
+    }
+
+    /*
+     * No parameters with RSA (only for EC)
+     */
+    if (*pk_alg == MBEDTLS_PK_RSA &&
+        ((params->tag != MBEDTLS_ASN1_NULL && params->tag != 0) ||
+         params->len != 0)) {
+        return MBEDTLS_ERR_PK_INVALID_ALG;
+    }
+
+    return 0;
+}
+
+/*
+ *  SubjectPublicKeyInfo  ::=  SEQUENCE  {
+ *       algorithm            AlgorithmIdentifier,
+ *       subjectPublicKey     BIT STRING }
+ */
+int mbedtls_pk_parse_subpubkey(unsigned char **p, const unsigned char *end,
+                               mbedtls_pk_context *pk)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    size_t len;
+    mbedtls_asn1_buf alg_params;
+    mbedtls_pk_type_t pk_alg = MBEDTLS_PK_NONE;
+    mbedtls_ecp_group_id ec_grp_id = MBEDTLS_ECP_DP_NONE;
+    const mbedtls_pk_info_t *pk_info;
+
+    if ((ret = mbedtls_asn1_get_tag(p, end, &len,
+                                    MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
+    }
+
+    end = *p + len;
+
+    if ((ret = pk_get_pk_alg(p, end, &pk_alg, &alg_params, &ec_grp_id)) != 0) {
+        return ret;
+    }
+
+    if ((ret = mbedtls_asn1_get_bitstring_null(p, end, &len)) != 0) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_INVALID_PUBKEY, ret);
+    }
+
+    if (*p + len != end) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_INVALID_PUBKEY,
+                                 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
+    }
+
+    if ((pk_info = mbedtls_pk_info_from_type(pk_alg)) == NULL) {
+        return MBEDTLS_ERR_PK_UNKNOWN_PK_ALG;
+    }
+
+    if ((ret = mbedtls_pk_setup(pk, pk_info)) != 0) {
+        return ret;
+    }
+
+#if defined(MBEDTLS_RSA_C)
+    if (pk_alg == MBEDTLS_PK_RSA) {
+        ret = mbedtls_rsa_parse_pubkey(mbedtls_pk_rsa(*pk), *p, (size_t) (end - *p));
+        if (ret == 0) {
+            /* On success all the input has been consumed by the parsing function. */
+            *p += end - *p;
+        } else if ((ret <= MBEDTLS_ERR_ASN1_OUT_OF_DATA) &&
+                   (ret >= MBEDTLS_ERR_ASN1_BUF_TOO_SMALL)) {
+            /* In case of ASN1 error codes add MBEDTLS_ERR_PK_INVALID_PUBKEY. */
+            ret = MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_INVALID_PUBKEY, ret);
+        } else {
+            ret = MBEDTLS_ERR_PK_INVALID_PUBKEY;
+        }
+    } else
+#endif /* MBEDTLS_RSA_C */
+#if defined(MBEDTLS_PK_HAVE_ECC_KEYS)
+    if (pk_alg == MBEDTLS_PK_ECKEY_DH || pk_alg == MBEDTLS_PK_ECKEY) {
+#if defined(MBEDTLS_PK_HAVE_RFC8410_CURVES)
+        if (MBEDTLS_PK_IS_RFC8410_GROUP_ID(ec_grp_id)) {
+            ret = pk_use_ecparams_rfc8410(&alg_params, ec_grp_id, pk);
+        } else
+#endif
+        {
+            ret = pk_use_ecparams(&alg_params, pk);
+        }
+        if (ret == 0) {
+            ret = mbedtls_pk_ecc_set_pubkey(pk, *p, (size_t) (end - *p));
+            *p += end - *p;
+        }
+    } else
+#endif /* MBEDTLS_PK_HAVE_ECC_KEYS */
+    ret = MBEDTLS_ERR_PK_UNKNOWN_PK_ALG;
+
+    if (ret == 0 && *p != end) {
+        ret = MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_INVALID_PUBKEY,
+                                MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
+    }
+
+    if (ret != 0) {
+        mbedtls_pk_free(pk);
+    }
+
+    return ret;
+}
+
+#if defined(MBEDTLS_PK_HAVE_ECC_KEYS)
+/*
+ * Parse a SEC1 encoded private EC key
+ */
+static int pk_parse_key_sec1_der(mbedtls_pk_context *pk,
+                                 const unsigned char *key, size_t keylen,
+                                 int (*f_rng)(void *, unsigned char *, size_t), void *p_rng)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    int version, pubkey_done;
+    size_t len, d_len;
+    mbedtls_asn1_buf params = { 0, 0, NULL };
+    unsigned char *p = (unsigned char *) key;
+    unsigned char *d;
+    unsigned char *end = p + keylen;
+    unsigned char *end2;
+
+    /*
+     * 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
+     *    }
+     */
+    if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
+                                    MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
+    }
+
+    end = p + len;
+
+    if ((ret = mbedtls_asn1_get_int(&p, end, &version)) != 0) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
+    }
+
+    if (version != 1) {
+        return MBEDTLS_ERR_PK_KEY_INVALID_VERSION;
+    }
+
+    if ((ret = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_OCTET_STRING)) != 0) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
+    }
+
+    /* Keep a reference to the position fo the private key. It will be used
+     * later in this function. */
+    d = p;
+    d_len = len;
+
+    p += len;
+
+    pubkey_done = 0;
+    if (p != end) {
+        /*
+         * Is 'parameters' present?
+         */
+        if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
+                                        MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED |
+                                        0)) == 0) {
+            if ((ret = pk_get_ecparams(&p, p + len, &params)) != 0 ||
+                (ret = pk_use_ecparams(&params, pk)) != 0) {
+                return ret;
+            }
+        } else if (ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG) {
+            return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
+        }
+    }
+
+    /*
+     * Load the private key
+     */
+    ret = mbedtls_pk_ecc_set_key(pk, d, d_len);
+    if (ret != 0) {
+        return ret;
+    }
+
+    if (p != end) {
+        /*
+         * Is 'publickey' present? If not, or if we can't read it (eg because it
+         * is compressed), create it from the private key.
+         */
+        if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
+                                        MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED |
+                                        1)) == 0) {
+            end2 = p + len;
+
+            if ((ret = mbedtls_asn1_get_bitstring_null(&p, end2, &len)) != 0) {
+                return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
+            }
+
+            if (p + len != end2) {
+                return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT,
+                                         MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
+            }
+
+            if ((ret = mbedtls_pk_ecc_set_pubkey(pk, p, (size_t) (end2 - p))) == 0) {
+                pubkey_done = 1;
+            } else {
+                /*
+                 * The only acceptable failure mode of mbedtls_pk_ecc_set_pubkey() above
+                 * is if the point format is not recognized.
+                 */
+                if (ret != MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE) {
+                    return MBEDTLS_ERR_PK_KEY_INVALID_FORMAT;
+                }
+            }
+        } else if (ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG) {
+            return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
+        }
+    }
+
+    if (!pubkey_done) {
+        if ((ret = mbedtls_pk_ecc_set_pubkey_from_prv(pk, d, d_len, f_rng, p_rng)) != 0) {
+            return ret;
+        }
+    }
+
+    return 0;
+}
+#endif /* MBEDTLS_PK_HAVE_ECC_KEYS */
+
+/***********************************************************************
+ *
+ *      PKCS#8 parsing functions
+ *
+ **********************************************************************/
+
+/*
+ * Parse an unencrypted PKCS#8 encoded private key
+ *
+ * Notes:
+ *
+ * - This function does not own the key buffer. It is the
+ *   responsibility of the caller to take care of zeroizing
+ *   and freeing it after use.
+ *
+ * - The function is responsible for freeing the provided
+ *   PK context on failure.
+ *
+ */
+static int pk_parse_key_pkcs8_unencrypted_der(
+    mbedtls_pk_context *pk,
+    const unsigned char *key, size_t keylen,
+    int (*f_rng)(void *, unsigned char *, size_t), void *p_rng)
+{
+    int ret, version;
+    size_t len;
+    mbedtls_asn1_buf params;
+    unsigned char *p = (unsigned char *) key;
+    unsigned char *end = p + keylen;
+    mbedtls_pk_type_t pk_alg = MBEDTLS_PK_NONE;
+    mbedtls_ecp_group_id ec_grp_id = MBEDTLS_ECP_DP_NONE;
+    const mbedtls_pk_info_t *pk_info;
+
+#if !defined(MBEDTLS_PK_HAVE_ECC_KEYS)
+    (void) f_rng;
+    (void) p_rng;
+#endif
+
+    /*
+     * This function parses the PrivateKeyInfo object (PKCS#8 v1.2 = RFC 5208)
+     *
+     *    PrivateKeyInfo ::= SEQUENCE {
+     *      version                   Version,
+     *      privateKeyAlgorithm       PrivateKeyAlgorithmIdentifier,
+     *      privateKey                PrivateKey,
+     *      attributes           [0]  IMPLICIT Attributes OPTIONAL }
+     *
+     *    Version ::= INTEGER
+     *    PrivateKeyAlgorithmIdentifier ::= AlgorithmIdentifier
+     *    PrivateKey ::= OCTET STRING
+     *
+     *  The PrivateKey OCTET STRING is a SEC1 ECPrivateKey
+     */
+
+    if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
+                                    MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
+    }
+
+    end = p + len;
+
+    if ((ret = mbedtls_asn1_get_int(&p, end, &version)) != 0) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
+    }
+
+    if (version != 0) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_VERSION, ret);
+    }
+
+    if ((ret = pk_get_pk_alg(&p, end, &pk_alg, &params, &ec_grp_id)) != 0) {
+        return ret;
+    }
+
+    if ((ret = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_OCTET_STRING)) != 0) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
+    }
+
+    if (len < 1) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT,
+                                 MBEDTLS_ERR_ASN1_OUT_OF_DATA);
+    }
+
+    if ((pk_info = mbedtls_pk_info_from_type(pk_alg)) == NULL) {
+        return MBEDTLS_ERR_PK_UNKNOWN_PK_ALG;
+    }
+
+    if ((ret = mbedtls_pk_setup(pk, pk_info)) != 0) {
+        return ret;
+    }
+
+#if defined(MBEDTLS_RSA_C)
+    if (pk_alg == MBEDTLS_PK_RSA) {
+        if ((ret = mbedtls_rsa_parse_key(mbedtls_pk_rsa(*pk), p, len)) != 0) {
+            mbedtls_pk_free(pk);
+            return ret;
+        }
+    } else
+#endif /* MBEDTLS_RSA_C */
+#if defined(MBEDTLS_PK_HAVE_ECC_KEYS)
+    if (pk_alg == MBEDTLS_PK_ECKEY || pk_alg == MBEDTLS_PK_ECKEY_DH) {
+#if defined(MBEDTLS_PK_HAVE_RFC8410_CURVES)
+        if (MBEDTLS_PK_IS_RFC8410_GROUP_ID(ec_grp_id)) {
+            if ((ret =
+                     pk_use_ecparams_rfc8410(&params, ec_grp_id, pk)) != 0 ||
+                (ret =
+                     pk_parse_key_rfc8410_der(pk, p, len, end, f_rng,
+                                              p_rng)) != 0) {
+                mbedtls_pk_free(pk);
+                return ret;
+            }
+        } else
+#endif
+        {
+            if ((ret = pk_use_ecparams(&params, pk)) != 0 ||
+                (ret = pk_parse_key_sec1_der(pk, p, len, f_rng, p_rng)) != 0) {
+                mbedtls_pk_free(pk);
+                return ret;
+            }
+        }
+    } else
+#endif /* MBEDTLS_PK_HAVE_ECC_KEYS */
+    return MBEDTLS_ERR_PK_UNKNOWN_PK_ALG;
+
+    end = p + len;
+    if (end != (key + keylen)) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT,
+                                 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
+    }
+
+    return 0;
+}
+
+/*
+ * Parse an encrypted PKCS#8 encoded private key
+ *
+ * To save space, the decryption happens in-place on the given key buffer.
+ * Also, while this function may modify the keybuffer, it doesn't own it,
+ * and instead it is the responsibility of the caller to zeroize and properly
+ * free it after use.
+ *
+ */
+#if defined(MBEDTLS_PKCS12_C) || defined(MBEDTLS_PKCS5_C)
+MBEDTLS_STATIC_TESTABLE int mbedtls_pk_parse_key_pkcs8_encrypted_der(
+    mbedtls_pk_context *pk,
+    unsigned char *key, size_t keylen,
+    const unsigned char *pwd, size_t pwdlen,
+    int (*f_rng)(void *, unsigned char *, size_t), void *p_rng)
+{
+    int ret, decrypted = 0;
+    size_t len;
+    unsigned char *buf;
+    unsigned char *p, *end;
+    mbedtls_asn1_buf pbe_alg_oid, pbe_params;
+#if defined(MBEDTLS_PKCS12_C) && defined(MBEDTLS_CIPHER_PADDING_PKCS7) && defined(MBEDTLS_CIPHER_C)
+    mbedtls_cipher_type_t cipher_alg;
+    mbedtls_md_type_t md_alg;
+#endif
+    size_t outlen = 0;
+
+    p = key;
+    end = p + keylen;
+
+    if (pwdlen == 0) {
+        return MBEDTLS_ERR_PK_PASSWORD_REQUIRED;
+    }
+
+    /*
+     * This function parses the EncryptedPrivateKeyInfo object (PKCS#8)
+     *
+     *  EncryptedPrivateKeyInfo ::= SEQUENCE {
+     *    encryptionAlgorithm  EncryptionAlgorithmIdentifier,
+     *    encryptedData        EncryptedData
+     *  }
+     *
+     *  EncryptionAlgorithmIdentifier ::= AlgorithmIdentifier
+     *
+     *  EncryptedData ::= OCTET STRING
+     *
+     *  The EncryptedData OCTET STRING is a PKCS#8 PrivateKeyInfo
+     *
+     */
+    if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
+                                    MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
+    }
+
+    end = p + len;
+
+    if ((ret = mbedtls_asn1_get_alg(&p, end, &pbe_alg_oid, &pbe_params)) != 0) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
+    }
+
+    if ((ret = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_OCTET_STRING)) != 0) {
+        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
+    }
+
+    buf = p;
+
+    /*
+     * Decrypt EncryptedData with appropriate PBE
+     */
+#if defined(MBEDTLS_PKCS12_C) && defined(MBEDTLS_CIPHER_PADDING_PKCS7) && defined(MBEDTLS_CIPHER_C)
+    if (mbedtls_oid_get_pkcs12_pbe_alg(&pbe_alg_oid, &md_alg, &cipher_alg) == 0) {
+        if ((ret = mbedtls_pkcs12_pbe_ext(&pbe_params, MBEDTLS_PKCS12_PBE_DECRYPT,
+                                          cipher_alg, md_alg,
+                                          pwd, pwdlen, p, len, buf, len, &outlen)) != 0) {
+            if (ret == MBEDTLS_ERR_PKCS12_PASSWORD_MISMATCH) {
+                return MBEDTLS_ERR_PK_PASSWORD_MISMATCH;
+            }
+
+            return ret;
+        }
+
+        decrypted = 1;
+    } else
+#endif /* MBEDTLS_PKCS12_C && MBEDTLS_CIPHER_PADDING_PKCS7 && MBEDTLS_CIPHER_C */
+#if defined(MBEDTLS_PKCS5_C) && defined(MBEDTLS_CIPHER_PADDING_PKCS7) && defined(MBEDTLS_CIPHER_C)
+    if (MBEDTLS_OID_CMP(MBEDTLS_OID_PKCS5_PBES2, &pbe_alg_oid) == 0) {
+        if ((ret = mbedtls_pkcs5_pbes2_ext(&pbe_params, MBEDTLS_PKCS5_DECRYPT, pwd, pwdlen,
+                                           p, len, buf, len, &outlen)) != 0) {
+            if (ret == MBEDTLS_ERR_PKCS5_PASSWORD_MISMATCH) {
+                return MBEDTLS_ERR_PK_PASSWORD_MISMATCH;
+            }
+
+            return ret;
+        }
+
+        decrypted = 1;
+    } else
+#endif /* MBEDTLS_PKCS5_C && MBEDTLS_CIPHER_PADDING_PKCS7 && MBEDTLS_CIPHER_C */
+    {
+        ((void) pwd);
+    }
+
+    if (decrypted == 0) {
+        return MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE;
+    }
+    return pk_parse_key_pkcs8_unencrypted_der(pk, buf, outlen, f_rng, p_rng);
+}
+#endif /* MBEDTLS_PKCS12_C || MBEDTLS_PKCS5_C */
+
+/***********************************************************************
+ *
+ *      Top-level functions, with format auto-discovery
+ *
+ **********************************************************************/
+
+/*
+ * Parse a private key
+ */
+int mbedtls_pk_parse_key(mbedtls_pk_context *pk,
+                         const unsigned char *key, size_t keylen,
+                         const unsigned char *pwd, size_t pwdlen,
+                         int (*f_rng)(void *, unsigned char *, size_t), void *p_rng)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    const mbedtls_pk_info_t *pk_info;
+#if defined(MBEDTLS_PEM_PARSE_C)
+    size_t len;
+    mbedtls_pem_context pem;
+#endif
+
+    if (keylen == 0) {
+        return MBEDTLS_ERR_PK_KEY_INVALID_FORMAT;
+    }
+
+#if defined(MBEDTLS_PEM_PARSE_C)
+    mbedtls_pem_init(&pem);
+
+#if defined(MBEDTLS_RSA_C)
+    /* Avoid calling mbedtls_pem_read_buffer() on non-null-terminated string */
+    if (key[keylen - 1] != '\0') {
+        ret = MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT;
+    } else {
+        ret = mbedtls_pem_read_buffer(&pem,
+                                      PEM_BEGIN_PRIVATE_KEY_RSA, PEM_END_PRIVATE_KEY_RSA,
+                                      key, pwd, pwdlen, &len);
+    }
+
+    if (ret == 0) {
+        pk_info = mbedtls_pk_info_from_type(MBEDTLS_PK_RSA);
+        if ((ret = mbedtls_pk_setup(pk, pk_info)) != 0 ||
+            (ret = mbedtls_rsa_parse_key(mbedtls_pk_rsa(*pk),
+                                         pem.buf, pem.buflen)) != 0) {
+            mbedtls_pk_free(pk);
+        }
+
+        mbedtls_pem_free(&pem);
+        return ret;
+    } else if (ret == MBEDTLS_ERR_PEM_PASSWORD_MISMATCH) {
+        return MBEDTLS_ERR_PK_PASSWORD_MISMATCH;
+    } else if (ret == MBEDTLS_ERR_PEM_PASSWORD_REQUIRED) {
+        return MBEDTLS_ERR_PK_PASSWORD_REQUIRED;
+    } else if (ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT) {
+        return ret;
+    }
+#endif /* MBEDTLS_RSA_C */
+
+#if defined(MBEDTLS_PK_HAVE_ECC_KEYS)
+    /* Avoid calling mbedtls_pem_read_buffer() on non-null-terminated string */
+    if (key[keylen - 1] != '\0') {
+        ret = MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT;
+    } else {
+        ret = mbedtls_pem_read_buffer(&pem,
+                                      PEM_BEGIN_PRIVATE_KEY_EC,
+                                      PEM_END_PRIVATE_KEY_EC,
+                                      key, pwd, pwdlen, &len);
+    }
+    if (ret == 0) {
+        pk_info = mbedtls_pk_info_from_type(MBEDTLS_PK_ECKEY);
+
+        if ((ret = mbedtls_pk_setup(pk, pk_info)) != 0 ||
+            (ret = pk_parse_key_sec1_der(pk,
+                                         pem.buf, pem.buflen,
+                                         f_rng, p_rng)) != 0) {
+            mbedtls_pk_free(pk);
+        }
+
+        mbedtls_pem_free(&pem);
+        return ret;
+    } else if (ret == MBEDTLS_ERR_PEM_PASSWORD_MISMATCH) {
+        return MBEDTLS_ERR_PK_PASSWORD_MISMATCH;
+    } else if (ret == MBEDTLS_ERR_PEM_PASSWORD_REQUIRED) {
+        return MBEDTLS_ERR_PK_PASSWORD_REQUIRED;
+    } else if (ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT) {
+        return ret;
+    }
+#endif /* MBEDTLS_PK_HAVE_ECC_KEYS */
+
+    /* Avoid calling mbedtls_pem_read_buffer() on non-null-terminated string */
+    if (key[keylen - 1] != '\0') {
+        ret = MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT;
+    } else {
+        ret = mbedtls_pem_read_buffer(&pem,
+                                      PEM_BEGIN_PRIVATE_KEY_PKCS8, PEM_END_PRIVATE_KEY_PKCS8,
+                                      key, NULL, 0, &len);
+    }
+    if (ret == 0) {
+        if ((ret = pk_parse_key_pkcs8_unencrypted_der(pk,
+                                                      pem.buf, pem.buflen, f_rng, p_rng)) != 0) {
+            mbedtls_pk_free(pk);
+        }
+
+        mbedtls_pem_free(&pem);
+        return ret;
+    } else if (ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT) {
+        return ret;
+    }
+
+#if defined(MBEDTLS_PKCS12_C) || defined(MBEDTLS_PKCS5_C)
+    /* Avoid calling mbedtls_pem_read_buffer() on non-null-terminated string */
+    if (key[keylen - 1] != '\0') {
+        ret = MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT;
+    } else {
+        ret = mbedtls_pem_read_buffer(&pem,
+                                      PEM_BEGIN_ENCRYPTED_PRIVATE_KEY_PKCS8,
+                                      PEM_END_ENCRYPTED_PRIVATE_KEY_PKCS8,
+                                      key, NULL, 0, &len);
+    }
+    if (ret == 0) {
+        if ((ret = mbedtls_pk_parse_key_pkcs8_encrypted_der(pk, pem.buf, pem.buflen,
+                                                            pwd, pwdlen, f_rng, p_rng)) != 0) {
+            mbedtls_pk_free(pk);
+        }
+
+        mbedtls_pem_free(&pem);
+        return ret;
+    } else if (ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT) {
+        return ret;
+    }
+#endif /* MBEDTLS_PKCS12_C || MBEDTLS_PKCS5_C */
+#else
+    ((void) pwd);
+    ((void) pwdlen);
+#endif /* MBEDTLS_PEM_PARSE_C */
+
+    /*
+     * At this point we only know it's not a PEM formatted key. Could be any
+     * of the known DER encoded private key formats
+     *
+     * We try the different DER format parsers to see if one passes without
+     * error
+     */
+#if defined(MBEDTLS_PKCS12_C) || defined(MBEDTLS_PKCS5_C)
+    if (pwdlen != 0) {
+        unsigned char *key_copy;
+
+        if ((key_copy = mbedtls_calloc(1, keylen)) == NULL) {
+            return MBEDTLS_ERR_PK_ALLOC_FAILED;
+        }
+
+        memcpy(key_copy, key, keylen);
+
+        ret = mbedtls_pk_parse_key_pkcs8_encrypted_der(pk, key_copy, keylen,
+                                                       pwd, pwdlen, f_rng, p_rng);
+
+        mbedtls_zeroize_and_free(key_copy, keylen);
+    }
+
+    if (ret == 0) {
+        return 0;
+    }
+
+    mbedtls_pk_free(pk);
+    mbedtls_pk_init(pk);
+
+    if (ret == MBEDTLS_ERR_PK_PASSWORD_MISMATCH) {
+        return ret;
+    }
+#endif /* MBEDTLS_PKCS12_C || MBEDTLS_PKCS5_C */
+
+    ret = pk_parse_key_pkcs8_unencrypted_der(pk, key, keylen, f_rng, p_rng);
+    if (ret == 0) {
+        return 0;
+    }
+
+    mbedtls_pk_free(pk);
+    mbedtls_pk_init(pk);
+
+#if defined(MBEDTLS_RSA_C)
+
+    pk_info = mbedtls_pk_info_from_type(MBEDTLS_PK_RSA);
+    if (mbedtls_pk_setup(pk, pk_info) == 0 &&
+        mbedtls_rsa_parse_key(mbedtls_pk_rsa(*pk), key, keylen) == 0) {
+        return 0;
+    }
+
+    mbedtls_pk_free(pk);
+    mbedtls_pk_init(pk);
+#endif /* MBEDTLS_RSA_C */
+
+#if defined(MBEDTLS_PK_HAVE_ECC_KEYS)
+    pk_info = mbedtls_pk_info_from_type(MBEDTLS_PK_ECKEY);
+    if (mbedtls_pk_setup(pk, pk_info) == 0 &&
+        pk_parse_key_sec1_der(pk,
+                              key, keylen, f_rng, p_rng) == 0) {
+        return 0;
+    }
+    mbedtls_pk_free(pk);
+#endif /* MBEDTLS_PK_HAVE_ECC_KEYS */
+
+    /* If MBEDTLS_RSA_C is defined but MBEDTLS_PK_HAVE_ECC_KEYS isn't,
+     * it is ok to leave the PK context initialized but not
+     * freed: It is the caller's responsibility to call pk_init()
+     * before calling this function, and to call pk_free()
+     * when it fails. If MBEDTLS_PK_HAVE_ECC_KEYS is defined but MBEDTLS_RSA_C
+     * isn't, this leads to mbedtls_pk_free() being called
+     * twice, once here and once by the caller, but this is
+     * also ok and in line with the mbedtls_pk_free() calls
+     * on failed PEM parsing attempts. */
+
+    return MBEDTLS_ERR_PK_KEY_INVALID_FORMAT;
+}
+
+/*
+ * Parse a public key
+ */
+int mbedtls_pk_parse_public_key(mbedtls_pk_context *ctx,
+                                const unsigned char *key, size_t keylen)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    unsigned char *p;
+#if defined(MBEDTLS_RSA_C)
+    const mbedtls_pk_info_t *pk_info;
+#endif
+#if defined(MBEDTLS_PEM_PARSE_C)
+    size_t len;
+    mbedtls_pem_context pem;
+#endif
+
+    if (keylen == 0) {
+        return MBEDTLS_ERR_PK_KEY_INVALID_FORMAT;
+    }
+
+#if defined(MBEDTLS_PEM_PARSE_C)
+    mbedtls_pem_init(&pem);
+#if defined(MBEDTLS_RSA_C)
+    /* Avoid calling mbedtls_pem_read_buffer() on non-null-terminated string */
+    if (key[keylen - 1] != '\0') {
+        ret = MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT;
+    } else {
+        ret = mbedtls_pem_read_buffer(&pem,
+                                      PEM_BEGIN_PUBLIC_KEY_RSA, PEM_END_PUBLIC_KEY_RSA,
+                                      key, NULL, 0, &len);
+    }
+
+    if (ret == 0) {
+        p = pem.buf;
+        if ((pk_info = mbedtls_pk_info_from_type(MBEDTLS_PK_RSA)) == NULL) {
+            mbedtls_pem_free(&pem);
+            return MBEDTLS_ERR_PK_UNKNOWN_PK_ALG;
+        }
+
+        if ((ret = mbedtls_pk_setup(ctx, pk_info)) != 0) {
+            mbedtls_pem_free(&pem);
+            return ret;
+        }
+
+        if ((ret = mbedtls_rsa_parse_pubkey(mbedtls_pk_rsa(*ctx), p, pem.buflen)) != 0) {
+            mbedtls_pk_free(ctx);
+        }
+
+        mbedtls_pem_free(&pem);
+        return ret;
+    } else if (ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT) {
+        mbedtls_pem_free(&pem);
+        return ret;
+    }
+#endif /* MBEDTLS_RSA_C */
+
+    /* Avoid calling mbedtls_pem_read_buffer() on non-null-terminated string */
+    if (key[keylen - 1] != '\0') {
+        ret = MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT;
+    } else {
+        ret = mbedtls_pem_read_buffer(&pem,
+                                      PEM_BEGIN_PUBLIC_KEY, PEM_END_PUBLIC_KEY,
+                                      key, NULL, 0, &len);
+    }
+
+    if (ret == 0) {
+        /*
+         * Was PEM encoded
+         */
+        p = pem.buf;
+
+        ret = mbedtls_pk_parse_subpubkey(&p, p + pem.buflen, ctx);
+        mbedtls_pem_free(&pem);
+        return ret;
+    } else if (ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT) {
+        mbedtls_pem_free(&pem);
+        return ret;
+    }
+    mbedtls_pem_free(&pem);
+#endif /* MBEDTLS_PEM_PARSE_C */
+
+#if defined(MBEDTLS_RSA_C)
+    if ((pk_info = mbedtls_pk_info_from_type(MBEDTLS_PK_RSA)) == NULL) {
+        return MBEDTLS_ERR_PK_UNKNOWN_PK_ALG;
+    }
+
+    if ((ret = mbedtls_pk_setup(ctx, pk_info)) != 0) {
+        return ret;
+    }
+
+    p = (unsigned char *) key;
+    ret = mbedtls_rsa_parse_pubkey(mbedtls_pk_rsa(*ctx), p, keylen);
+    if (ret == 0) {
+        return ret;
+    }
+    mbedtls_pk_free(ctx);
+    if (ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG) {
+        return ret;
+    }
+#endif /* MBEDTLS_RSA_C */
+    p = (unsigned char *) key;
+
+    ret = mbedtls_pk_parse_subpubkey(&p, p + keylen, ctx);
+
+    return ret;
+}
+
+/***********************************************************************
+ *
+ *      Top-level functions, with filesystem support
+ *
+ **********************************************************************/
+
+#if defined(MBEDTLS_FS_IO)
+/*
+ * Load all data from a file into a given buffer.
+ *
+ * The file is expected to contain either PEM or DER encoded data.
+ * A terminating null byte is always appended. It is included in the announced
+ * length only if the data looks like it is PEM encoded.
+ */
+int mbedtls_pk_load_file(const char *path, unsigned char **buf, size_t *n)
+{
+    FILE *f;
+    long size;
+
+    if ((f = fopen(path, "rb")) == NULL) {
+        return MBEDTLS_ERR_PK_FILE_IO_ERROR;
+    }
+
+    /* Ensure no stdio buffering of secrets, as such buffers cannot be wiped. */
+    mbedtls_setbuf(f, NULL);
+
+    fseek(f, 0, SEEK_END);
+    if ((size = ftell(f)) == -1) {
+        fclose(f);
+        return MBEDTLS_ERR_PK_FILE_IO_ERROR;
+    }
+    fseek(f, 0, SEEK_SET);
+
+    *n = (size_t) size;
+
+    if (*n + 1 == 0 ||
+        (*buf = mbedtls_calloc(1, *n + 1)) == NULL) {
+        fclose(f);
+        return MBEDTLS_ERR_PK_ALLOC_FAILED;
+    }
+
+    if (fread(*buf, 1, *n, f) != *n) {
+        fclose(f);
+
+        mbedtls_zeroize_and_free(*buf, *n);
+
+        return MBEDTLS_ERR_PK_FILE_IO_ERROR;
+    }
+
+    fclose(f);
+
+    (*buf)[*n] = '\0';
+
+    if (strstr((const char *) *buf, "-----BEGIN ") != NULL) {
+        ++*n;
+    }
+
+    return 0;
+}
+
+/*
+ * Load and parse a private key
+ */
+int mbedtls_pk_parse_keyfile(mbedtls_pk_context *ctx,
+                             const char *path, const char *pwd,
+                             int (*f_rng)(void *, unsigned char *, size_t), void *p_rng)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    size_t n;
+    unsigned char *buf;
+
+    if ((ret = mbedtls_pk_load_file(path, &buf, &n)) != 0) {
+        return ret;
+    }
+
+    if (pwd == NULL) {
+        ret = mbedtls_pk_parse_key(ctx, buf, n, NULL, 0, f_rng, p_rng);
+    } else {
+        ret = mbedtls_pk_parse_key(ctx, buf, n,
+                                   (const unsigned char *) pwd, strlen(pwd), f_rng, p_rng);
+    }
+
+    mbedtls_zeroize_and_free(buf, n);
+
+    return ret;
+}
+
+/*
+ * Load and parse a public key
+ */
+int mbedtls_pk_parse_public_keyfile(mbedtls_pk_context *ctx, const char *path)
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    size_t n;
+    unsigned char *buf;
+
+    if ((ret = mbedtls_pk_load_file(path, &buf, &n)) != 0) {
+        return ret;
+    }
+
+    ret = mbedtls_pk_parse_public_key(ctx, buf, n);
+
+    mbedtls_zeroize_and_free(buf, n);
+
+    return ret;
+}
+#endif /* MBEDTLS_FS_IO */
+
+#endif /* MBEDTLS_PK_PARSE_C */