diff --git a/ChangeLog.d/add-subjectAltName-certs.txt b/ChangeLog.d/add-subjectAltName-certs.txt
new file mode 100644
index 0000000..487e5c6
--- /dev/null
+++ b/ChangeLog.d/add-subjectAltName-certs.txt
@@ -0,0 +1,6 @@
+Features
+   * It is now possible to generate certificates with SubjectAltNames.
+     Currently supported subtypes: DnsName, UniformResourceIdentifier,
+     IP address, OtherName, and DirectoryName, as defined in RFC 5280.
+     See mbedtls_x509write_crt_set_subject_alternative_name for
+     more information.
diff --git a/include/mbedtls/psa_util.h b/include/mbedtls/psa_util.h
index f7ed2eb..64c2435 100644
--- a/include/mbedtls/psa_util.h
+++ b/include/mbedtls/psa_util.h
@@ -248,6 +248,22 @@
 #endif /* MBEDTLS_ECP_DP_BP512R1_ENABLED */
             }
             break;
+        case PSA_ECC_FAMILY_MONTGOMERY:
+            switch (bits) {
+#if defined(MBEDTLS_ECP_DP_CURVE25519_ENABLED)
+                case 255:
+                    *oid = MBEDTLS_OID_X25519;
+                    *oid_len = MBEDTLS_OID_SIZE(MBEDTLS_OID_X25519);
+                    return 0;
+#endif /* MBEDTLS_ECP_DP_CURVE25519_ENABLED */
+#if defined(MBEDTLS_ECP_DP_CURVE448_ENABLED)
+                case 448:
+                    *oid = MBEDTLS_OID_X448;
+                    *oid_len = MBEDTLS_OID_SIZE(MBEDTLS_OID_X448);
+                    return 0;
+#endif /* MBEDTLS_ECP_DP_CURVE448_ENABLED */
+            }
+            break;
     }
     (void) oid;
     (void) oid_len;
diff --git a/include/mbedtls/x509.h b/include/mbedtls/x509.h
index 7faf176..df6d762 100644
--- a/include/mbedtls/x509.h
+++ b/include/mbedtls/x509.h
@@ -304,7 +304,7 @@
 typedef struct mbedtls_x509_subject_alternative_name {
     int type;                              /**< The SAN type, value of MBEDTLS_X509_SAN_XXX. */
     union {
-        mbedtls_x509_san_other_name other_name; /**< The otherName supported type. */
+        mbedtls_x509_san_other_name other_name;
         mbedtls_x509_name directory_name;
         mbedtls_x509_buf unstructured_name; /**< The buffer for the unstructured types. rfc822Name, dnsName and uniformResourceIdentifier are currently supported. */
     }
@@ -312,6 +312,12 @@
 }
 mbedtls_x509_subject_alternative_name;
 
+typedef struct mbedtls_x509_san_list {
+    mbedtls_x509_subject_alternative_name node;
+    struct mbedtls_x509_san_list *next;
+}
+mbedtls_x509_san_list;
+
 /** \} name Structures for parsing X.509 certificates, CRLs and CSRs */
 
 /**
@@ -401,7 +407,8 @@
  *                 of the subject alternative name encoded in \p san_raw.
  *
  * \note           Supported GeneralName types, as defined in RFC 5280:
- *                 "rfc822Name", "dnsName", "uniformResourceIdentifier" and "hardware_module_name"
+ *                 "rfc822Name", "dnsName", "directoryName",
+ *                 "uniformResourceIdentifier" and "hardware_module_name"
  *                 of type "otherName", as defined in RFC 4108.
  *
  * \note           This function should be called on a single raw data of
diff --git a/include/mbedtls/x509_crt.h b/include/mbedtls/x509_crt.h
index e1b4aa2..acb2344 100644
--- a/include/mbedtls/x509_crt.h
+++ b/include/mbedtls/x509_crt.h
@@ -75,7 +75,7 @@
     mbedtls_x509_buf issuer_id;         /**< Optional X.509 v2/v3 issuer unique identifier. */
     mbedtls_x509_buf subject_id;        /**< Optional X.509 v2/v3 subject unique identifier. */
     mbedtls_x509_buf v3_ext;            /**< Optional X.509 v3 extensions.  */
-    mbedtls_x509_sequence subject_alt_names;    /**< Optional list of raw entries of Subject Alternative Names extension (currently only dNSName, uniformResourceIdentifier, DirectoryName and OtherName are listed). */
+    mbedtls_x509_sequence subject_alt_names; /**< Optional list of raw entries of Subject Alternative Names extension. These can be later parsed by mbedtls_x509_parse_subject_alt_name. */
     mbedtls_x509_buf subject_key_id;    /**< Optional X.509 v3 extension subject key identifier. */
     mbedtls_x509_authority authority_key_id;    /**< Optional X.509 v3 extension authority key identifier. */
 
@@ -242,6 +242,21 @@
 mbedtls_x509write_cert;
 
 /**
+ * \brief           Set Subject Alternative Name
+ *
+ * \param ctx       Certificate context to use
+ * \param san_list  List of SAN values
+ *
+ * \return          0 if successful, or MBEDTLS_ERR_X509_ALLOC_FAILED
+ *
+ * \note            "dnsName", "uniformResourceIdentifier", "IP address",
+ *                  "otherName", and "DirectoryName", as defined in RFC 5280,
+ *                  are supported.
+ */
+int mbedtls_x509write_crt_set_subject_alternative_name(mbedtls_x509write_cert *ctx,
+                                                       const mbedtls_x509_san_list *san_list);
+
+/**
  * Item in a verification chain: cert and flags for it
  */
 typedef struct {
diff --git a/include/mbedtls/x509_csr.h b/include/mbedtls/x509_csr.h
index f3f9e13..80adb19 100644
--- a/include/mbedtls/x509_csr.h
+++ b/include/mbedtls/x509_csr.h
@@ -60,7 +60,7 @@
 
     unsigned int key_usage;     /**< Optional key usage extension value: See the values in x509.h */
     unsigned char ns_cert_type; /**< Optional Netscape certificate type extension value: See the values in x509.h */
-    mbedtls_x509_sequence subject_alt_names;    /**< Optional list of raw entries of Subject Alternative Names extension (currently only dNSName and OtherName are listed). */
+    mbedtls_x509_sequence subject_alt_names; /**< Optional list of raw entries of Subject Alternative Names extension. These can be later parsed by mbedtls_x509_parse_subject_alt_name. */
 
     int MBEDTLS_PRIVATE(ext_types);              /**< Bit string containing detected and parsed extensions */
 
@@ -83,12 +83,6 @@
 }
 mbedtls_x509write_csr;
 
-typedef struct mbedtls_x509_san_list {
-    mbedtls_x509_subject_alternative_name node;
-    struct mbedtls_x509_san_list *next;
-}
-mbedtls_x509_san_list;
-
 #if defined(MBEDTLS_X509_CSR_PARSE_C)
 /**
  * \brief          Load a Certificate Signing Request (CSR) in DER format
diff --git a/library/pk.c b/library/pk.c
index 8e42b8d..d30205c 100644
--- a/library/pk.c
+++ b/library/pk.c
@@ -825,7 +825,8 @@
             return MBEDTLS_ERR_PK_TYPE_MISMATCH;
         }
     } else {
-        if (pub->pk_info != prv->pk_info) {
+        if ((prv->pk_info->type != MBEDTLS_PK_OPAQUE) &&
+            (pub->pk_info != prv->pk_info)) {
             return MBEDTLS_ERR_PK_TYPE_MISMATCH;
         }
     }
diff --git a/library/pk_internal.h b/library/pk_internal.h
index 8d4b005..388f94a 100644
--- a/library/pk_internal.h
+++ b/library/pk_internal.h
@@ -84,11 +84,30 @@
 static inline mbedtls_ecp_group_id mbedtls_pk_get_group_id(const mbedtls_pk_context *pk)
 {
     mbedtls_ecp_group_id id;
+
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+    if (mbedtls_pk_get_type(pk) == MBEDTLS_PK_OPAQUE) {
+        psa_key_attributes_t opaque_attrs = PSA_KEY_ATTRIBUTES_INIT;
+        psa_key_type_t opaque_key_type;
+        psa_ecc_family_t curve;
+
+        if (psa_get_key_attributes(pk->priv_id, &opaque_attrs) != PSA_SUCCESS) {
+            return MBEDTLS_ECP_DP_NONE;
+        }
+        opaque_key_type = psa_get_key_type(&opaque_attrs);
+        curve = PSA_KEY_TYPE_ECC_GET_FAMILY(opaque_key_type);
+        id = mbedtls_ecc_group_of_psa(curve, psa_get_key_bits(&opaque_attrs), 0);
+        psa_reset_key_attributes(&opaque_attrs);
+    } else
+#endif /* MBEDTLS_USE_PSA_CRYPTO */
+    {
 #if defined(MBEDTLS_PK_USE_PSA_EC_DATA)
-    id = mbedtls_ecc_group_of_psa(pk->ec_family, pk->ec_bits, 0);
+        id = mbedtls_ecc_group_of_psa(pk->ec_family, pk->ec_bits, 0);
 #else /* MBEDTLS_PK_USE_PSA_EC_DATA */
-    id = mbedtls_pk_ec_ro(*pk)->grp.id;
+        id = mbedtls_pk_ec_ro(*pk)->grp.id;
 #endif /* MBEDTLS_PK_USE_PSA_EC_DATA */
+    }
+
     return id;
 }
 
diff --git a/library/pk_wrap.c b/library/pk_wrap.c
index 92937c8..9170231 100644
--- a/library/pk_wrap.c
+++ b/library/pk_wrap.c
@@ -1669,6 +1669,53 @@
 #endif /* !MBEDTLS_PK_CAN_ECDSA_SIGN && !MBEDTLS_RSA_C */
 }
 
+static int pk_opaque_ec_check_pair(mbedtls_pk_context *pub, mbedtls_pk_context *prv,
+                                   int (*f_rng)(void *, unsigned char *, size_t),
+                                   void *p_rng)
+{
+    /* The main difference between this function and eckey_check_pair_psa() is
+     * that in the opaque case the private key is always stored in PSA side no
+     * matter if MBEDTLS_PK_USE_PSA_EC_DATA is enabled or not.
+     * When MBEDTLS_PK_USE_PSA_EC_DATA is enabled, we can simply use the
+     * eckey_check_pair_psa(). */
+    (void) f_rng;
+    (void) p_rng;
+
+#if defined(MBEDTLS_PK_USE_PSA_EC_DATA)
+    return eckey_check_pair_psa(pub, prv);
+#elif defined(MBEDTLS_ECP_LIGHT)
+    psa_status_t status;
+    uint8_t exp_pub_key[MBEDTLS_PK_MAX_EC_PUBKEY_RAW_LEN];
+    size_t exp_pub_key_len = 0;
+    uint8_t pub_key[MBEDTLS_PK_MAX_EC_PUBKEY_RAW_LEN];
+    size_t pub_key_len = 0;
+    int ret;
+
+    status = psa_export_public_key(prv->priv_id, exp_pub_key, sizeof(exp_pub_key),
+                                   &exp_pub_key_len);
+    if (status != PSA_SUCCESS) {
+        ret = psa_pk_status_to_mbedtls(status);
+        return ret;
+    }
+    ret = mbedtls_ecp_point_write_binary(&(mbedtls_pk_ec_ro(*pub)->grp),
+                                         &(mbedtls_pk_ec_ro(*pub)->Q),
+                                         MBEDTLS_ECP_PF_UNCOMPRESSED,
+                                         &pub_key_len, pub_key, sizeof(pub_key));
+    if (ret != 0) {
+        return ret;
+    }
+    if ((exp_pub_key_len != pub_key_len) ||
+        memcmp(exp_pub_key, pub_key, exp_pub_key_len)) {
+        return MBEDTLS_ERR_PK_BAD_INPUT_DATA;
+    }
+    return 0;
+#else
+    (void) pub;
+    (void) prv;
+    return MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE;
+#endif /* !MBEDTLS_PK_USE_PSA_EC_DATA */
+}
+
 const mbedtls_pk_info_t mbedtls_pk_ecdsa_opaque_info = {
     MBEDTLS_PK_OPAQUE,
     "Opaque",
@@ -1682,7 +1729,7 @@
 #endif
     NULL, /* decrypt - not relevant */
     NULL, /* encrypt - not relevant */
-    NULL, /* check_pair - could be done later or left NULL */
+    pk_opaque_ec_check_pair,
     NULL, /* alloc - no need to allocate new data dynamically */
     NULL, /* free - as for the alloc, there is no data to free */
 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
diff --git a/library/pkwrite.c b/library/pkwrite.c
index d684815..218d0c1 100644
--- a/library/pkwrite.c
+++ b/library/pkwrite.c
@@ -58,7 +58,8 @@
 #include "mbedtls/platform.h"
 
 /* Helper for Montgomery curves */
-#if defined(MBEDTLS_ECP_LIGHT) && defined(MBEDTLS_PK_HAVE_RFC8410_CURVES)
+#if defined(MBEDTLS_ECP_LIGHT)
+#if defined(MBEDTLS_PK_HAVE_RFC8410_CURVES)
 static inline int mbedtls_pk_is_rfc8410(const mbedtls_pk_context *pk)
 {
     mbedtls_ecp_group_id id = mbedtls_pk_get_group_id(pk);
@@ -75,7 +76,41 @@
 #endif
     return 0;
 }
-#endif /* MBEDTLS_ECP_LIGHT && MBEDTLS_PK_HAVE_RFC8410_CURVES */
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+/* It is assumed that the input key is opaque */
+static psa_ecc_family_t pk_get_opaque_ec_family(const mbedtls_pk_context *pk)
+{
+    psa_ecc_family_t ec_family = 0;
+    psa_key_attributes_t key_attrs = PSA_KEY_ATTRIBUTES_INIT;
+
+    if (psa_get_key_attributes(pk->priv_id, &key_attrs) != PSA_SUCCESS) {
+        return 0;
+    }
+    ec_family = PSA_KEY_TYPE_ECC_GET_FAMILY(psa_get_key_type(&key_attrs));
+    psa_reset_key_attributes(&key_attrs);
+
+    return ec_family;
+}
+#endif /* MBETLS_USE_PSA_CRYPTO */
+#endif /* MBEDTLS_PK_HAVE_RFC8410_CURVES */
+#endif /* MBEDTLS_ECP_LIGHT */
+
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+/* It is assumed that the input key is opaque */
+static psa_key_type_t pk_get_opaque_key_type(const mbedtls_pk_context *pk)
+{
+    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 0;
+    }
+    opaque_key_type = psa_get_key_type(&opaque_attrs);
+    psa_reset_key_attributes(&opaque_attrs);
+
+    return opaque_key_type;
+}
+#endif /* MBETLS_USE_PSA_CRYPTO */
 
 #if defined(MBEDTLS_RSA_C)
 /*
@@ -85,11 +120,12 @@
  *  }
  */
 static int pk_write_rsa_pubkey(unsigned char **p, unsigned char *start,
-                               mbedtls_rsa_context *rsa)
+                               const mbedtls_pk_context *pk)
 {
     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
     size_t len = 0;
     mbedtls_mpi T;
+    mbedtls_rsa_context *rsa = mbedtls_pk_rsa(*pk);
 
     mbedtls_mpi_init(&T);
 
@@ -123,29 +159,20 @@
 #endif /* MBEDTLS_RSA_C */
 
 #if defined(MBEDTLS_ECP_LIGHT)
+#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[PSA_EXPORT_KEY_PAIR_MAX_SIZE];
 
-#if defined(MBEDTLS_PK_USE_PSA_EC_DATA)
-    len = pk->pub_raw_len;
-
-    if (*p < start || (size_t) (*p - start) < len) {
-        return MBEDTLS_ERR_ASN1_BUF_TOO_SMALL;
-    }
-
-    memcpy(*p - len, pk->pub_raw, len);
-    *p -= len;
-#else
-    unsigned char buf[MBEDTLS_ECP_MAX_PT_LEN];
-    mbedtls_ecp_keypair *ec = mbedtls_pk_ec(*pk);
-    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
-
-    if ((ret = mbedtls_ecp_point_write_binary(&ec->grp, &ec->Q,
-                                              MBEDTLS_ECP_PF_UNCOMPRESSED,
-                                              &len, buf, sizeof(buf))) != 0) {
-        return ret;
+    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) {
@@ -154,10 +181,50 @@
 
     *p -= len;
     memcpy(*p, buf, len);
-#endif
 
     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;
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+    uint8_t buf[PSA_EXPORT_PUBLIC_KEY_MAX_SIZE];
+#else
+    unsigned char buf[MBEDTLS_ECP_MAX_PT_LEN];
+#endif /* MBEDTLS_USE_PSA_CRYPTO */
+    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 */
 
 /*
  * ECParameters ::= CHOICE {
@@ -184,38 +251,97 @@
 /*
  * 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;
-
-#if defined(MBEDTLS_PK_USE_PSA_EC_DATA)
     unsigned char tmp[MBEDTLS_PSA_MAX_EC_KEY_PAIR_LENGTH];
     psa_status_t status;
 
-    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;
+    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;
+        }
     }
-#else /* MBEDTLS_PK_USE_PSA_EC_DATA */
-    unsigned char tmp[MBEDTLS_ECP_MAX_BYTES];
-    mbedtls_ecp_keypair *ec = mbedtls_pk_ec_rw(*pk);
-    byte_length = (ec->grp.pbits + 7) / 8;
 
-    ret = mbedtls_ecp_write_key(ec, tmp, byte_length);
-    if (ret != 0) {
-        goto exit;
-    }
-#endif /* MBEDTLS_PK_USE_PSA_EC_DATA */
     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;
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+    unsigned char tmp[MBEDTLS_PSA_MAX_EC_KEY_PAIR_LENGTH];
+    psa_status_t status;
+#else
+    unsigned char tmp[MBEDTLS_ECP_MAX_BYTES];
+#endif /* MBEDTLS_USE_PSA_CRYPTO */
+
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+    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(ec, tmp, byte_length);
+        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 */
 #endif /* MBEDTLS_ECP_LIGHT */
 
+#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 */
+
 int mbedtls_pk_write_pubkey(unsigned char **p, unsigned char *start,
                             const mbedtls_pk_context *key)
 {
@@ -224,7 +350,7 @@
 
 #if defined(MBEDTLS_RSA_C)
     if (mbedtls_pk_get_type(key) == MBEDTLS_PK_RSA) {
-        MBEDTLS_ASN1_CHK_ADD(len, pk_write_rsa_pubkey(p, start, mbedtls_pk_rsa(*key)));
+        MBEDTLS_ASN1_CHK_ADD(len, pk_write_rsa_pubkey(p, start, key));
     } else
 #endif
 #if defined(MBEDTLS_ECP_LIGHT)
@@ -234,20 +360,7 @@
 #endif
 #if defined(MBEDTLS_USE_PSA_CRYPTO)
     if (mbedtls_pk_get_type(key) == MBEDTLS_PK_OPAQUE) {
-        size_t buffer_size;
-
-        if (*p < start) {
-            return MBEDTLS_ERR_PK_BAD_INPUT_DATA;
-        }
-
-        buffer_size = (size_t) (*p - start);
-        if (psa_export_public_key(key->priv_id, start, buffer_size, &len)
-            != PSA_SUCCESS) {
-            return MBEDTLS_ERR_PK_BAD_INPUT_DATA;
-        } else {
-            *p -= len;
-            memmove(*p, start, len);
-        }
+        MBEDTLS_ASN1_CHK_ADD(len, pk_write_opaque_pubkey(p, start, key));
     } else
 #endif /* MBEDTLS_USE_PSA_CRYPTO */
     return MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE;
@@ -293,44 +406,22 @@
     pk_type = mbedtls_pk_get_type(key);
 #if defined(MBEDTLS_ECP_LIGHT)
     if (pk_type == MBEDTLS_PK_ECKEY) {
-#if defined(MBEDTLS_ECP_C)
-        ec_grp_id = mbedtls_pk_ec_ro(*key)->grp.id;
-#else /* MBEDTLS_ECP_C */
-        ec_grp_id = mbedtls_ecc_group_of_psa(key->ec_family, key->ec_bits, 0);
-#endif /* MBEDTLS_ECP_C */
+        ec_grp_id = mbedtls_pk_get_group_id(key);
     }
 #endif /* MBEDTLS_ECP_LIGHT */
 #if defined(MBEDTLS_USE_PSA_CRYPTO)
     if (pk_type == MBEDTLS_PK_OPAQUE) {
-        psa_key_attributes_t attributes = PSA_KEY_ATTRIBUTES_INIT;
-        psa_key_type_t key_type;
-
-        if (PSA_SUCCESS != psa_get_key_attributes(key->priv_id,
-                                                  &attributes)) {
-            return MBEDTLS_ERR_PLATFORM_HW_ACCEL_FAILED;
-        }
-        key_type = psa_get_key_type(&attributes);
-
+        psa_key_type_t opaque_key_type = pk_get_opaque_key_type(key);
 #if defined(MBEDTLS_ECP_LIGHT)
-        if (PSA_KEY_TYPE_IS_ECC_KEY_PAIR(key_type)) {
-            psa_ecc_family_t curve;
-
-            curve = PSA_KEY_TYPE_ECC_GET_FAMILY(key_type);
-            if (curve != 0) {
-                ec_grp_id = mbedtls_ecc_group_of_psa(curve, psa_get_key_bits(&attributes), 0);
-                if (ec_grp_id != MBEDTLS_ECP_DP_NONE) {
-                    /* The rest of the function works as for legacy EC contexts. */
-                    pk_type = MBEDTLS_PK_ECKEY;
-                }
-            }
-        }
+        if (PSA_KEY_TYPE_IS_ECC(opaque_key_type)) {
+            pk_type = MBEDTLS_PK_ECKEY;
+            ec_grp_id = mbedtls_pk_get_group_id(key);
+        } else
 #endif /* MBEDTLS_ECP_LIGHT */
-        if (PSA_KEY_TYPE_IS_RSA(key_type)) {
+        if (PSA_KEY_TYPE_IS_RSA(opaque_key_type)) {
             /* The rest of the function works as for legacy RSA contexts. */
             pk_type = MBEDTLS_PK_RSA;
         }
-
-        psa_reset_key_attributes(&attributes);
     }
     /* `pk_type` will have been changed to non-opaque by here if this function can handle it */
     if (pk_type == MBEDTLS_PK_OPAQUE) {
@@ -340,11 +431,13 @@
 
 #if defined(MBEDTLS_ECP_LIGHT)
     if (pk_type == MBEDTLS_PK_ECKEY) {
-        /* Some groups have their own AlgorithmIdentifier OID, others are handled by mbedtls_oid_get_oid_by_pk_alg() below */
+        /* Some groups have their own AlgorithmIdentifier OID, others are handled
+         * by mbedtls_oid_get_oid_by_pk_alg() below */
         ret = mbedtls_oid_get_oid_by_ec_grp_algid(ec_grp_id, &oid, &oid_len);
 
         if (ret == 0) {
-            /* Currently, none of the supported algorithms that have their own AlgorithmIdentifier OID have any parameters */
+            /* Currently, none of the supported algorithms that have their own
+             * AlgorithmIdentifier OID have any parameters */
             has_par = 0;
         } else if (ret == MBEDTLS_ERR_OID_NOT_FOUND) {
             MBEDTLS_ASN1_CHK_ADD(par_len, pk_write_ec_param(&c, buf, ec_grp_id));
@@ -420,27 +513,91 @@
     return (int) len;
 }
 #endif /* MBEDTLS_PK_HAVE_RFC8410_CURVES */
-#endif /* MBEDTLS_ECP_LIGHT */
 
-int mbedtls_pk_write_key_der(const mbedtls_pk_context *key, unsigned char *buf, size_t size)
+/*
+ * 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)
 {
-    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
-    unsigned char *c;
     size_t len = 0;
-#if defined(MBEDTLS_ECP_LIGHT)
+    int ret;
+    size_t pub_len = 0, par_len = 0;
     mbedtls_ecp_group_id grp_id;
-#endif
 
-    if (size == 0) {
+    /* 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;
 
-    c = buf + size;
+    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_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_ECP_LIGHT */
 
 #if defined(MBEDTLS_RSA_C)
-    if (mbedtls_pk_get_type(key) == MBEDTLS_PK_RSA) {
+static int pk_write_rsa_der(unsigned char **p, unsigned char *buf,
+                            const mbedtls_pk_context *pk)
+{
+    size_t len = 0;
+    int ret;
+
+#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 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));
+    } else
+#endif /* MBEDTLS_USE_PSA_CRYPTO */
+    {
         mbedtls_mpi T; /* Temporary holding the exported parameters */
-        mbedtls_rsa_context *rsa = mbedtls_pk_rsa(*key);
+        mbedtls_rsa_context *rsa = mbedtls_pk_rsa(*pk);
 
         /*
          * Export the parameters one after another to avoid simultaneous copies.
@@ -450,21 +607,21 @@
 
         /* Export QP */
         if ((ret = mbedtls_rsa_export_crt(rsa, NULL, NULL, &T)) != 0 ||
-            (ret = mbedtls_asn1_write_mpi(&c, buf, &T)) < 0) {
+            (ret = mbedtls_asn1_write_mpi(p, buf, &T)) < 0) {
             goto end_of_export;
         }
         len += ret;
 
         /* Export DQ */
         if ((ret = mbedtls_rsa_export_crt(rsa, NULL, &T, NULL)) != 0 ||
-            (ret = mbedtls_asn1_write_mpi(&c, buf, &T)) < 0) {
+            (ret = mbedtls_asn1_write_mpi(p, buf, &T)) < 0) {
             goto end_of_export;
         }
         len += ret;
 
         /* Export DP */
         if ((ret = mbedtls_rsa_export_crt(rsa, &T, NULL, NULL)) != 0 ||
-            (ret = mbedtls_asn1_write_mpi(&c, buf, &T)) < 0) {
+            (ret = mbedtls_asn1_write_mpi(p, buf, &T)) < 0) {
             goto end_of_export;
         }
         len += ret;
@@ -472,7 +629,7 @@
         /* Export Q */
         if ((ret = mbedtls_rsa_export(rsa, NULL, NULL,
                                       &T, NULL, NULL)) != 0 ||
-            (ret = mbedtls_asn1_write_mpi(&c, buf, &T)) < 0) {
+            (ret = mbedtls_asn1_write_mpi(p, buf, &T)) < 0) {
             goto end_of_export;
         }
         len += ret;
@@ -480,7 +637,7 @@
         /* Export P */
         if ((ret = mbedtls_rsa_export(rsa, NULL, &T,
                                       NULL, NULL, NULL)) != 0 ||
-            (ret = mbedtls_asn1_write_mpi(&c, buf, &T)) < 0) {
+            (ret = mbedtls_asn1_write_mpi(p, buf, &T)) < 0) {
             goto end_of_export;
         }
         len += ret;
@@ -488,7 +645,7 @@
         /* Export D */
         if ((ret = mbedtls_rsa_export(rsa, NULL, NULL,
                                       NULL, &T, NULL)) != 0 ||
-            (ret = mbedtls_asn1_write_mpi(&c, buf, &T)) < 0) {
+            (ret = mbedtls_asn1_write_mpi(p, buf, &T)) < 0) {
             goto end_of_export;
         }
         len += ret;
@@ -496,7 +653,7 @@
         /* Export E */
         if ((ret = mbedtls_rsa_export(rsa, NULL, NULL,
                                       NULL, NULL, &T)) != 0 ||
-            (ret = mbedtls_asn1_write_mpi(&c, buf, &T)) < 0) {
+            (ret = mbedtls_asn1_write_mpi(p, buf, &T)) < 0) {
             goto end_of_export;
         }
         len += ret;
@@ -504,7 +661,7 @@
         /* Export N */
         if ((ret = mbedtls_rsa_export(rsa, &T, NULL,
                                       NULL, NULL, NULL)) != 0 ||
-            (ret = mbedtls_asn1_write_mpi(&c, buf, &T)) < 0) {
+            (ret = mbedtls_asn1_write_mpi(p, buf, &T)) < 0) {
             goto end_of_export;
         }
         len += ret;
@@ -516,71 +673,62 @@
             return ret;
         }
 
-        MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_int(&c, buf, 0));
-        MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(&c, buf, len));
-        MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_tag(&c,
+        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_RSA_C */
+
+int mbedtls_pk_write_key_der(const mbedtls_pk_context *key, unsigned char *buf, size_t size)
+{
+    unsigned char *c;
+    size_t len = 0;
+#if defined(MBEDTLS_RSA_C)
+    int is_rsa_opaque = 0;
+#endif /* MBEDTLS_RSA_C */
+#if defined(MBEDTLS_ECP_LIGHT)
+    int is_ec_opaque = 0;
+#endif /* MBEDTLS_ECP_LIGHT */
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+    psa_key_type_t opaque_key_type;
+#endif /* MBEDTLS_USE_PSA_CRYPTO */
+
+    if (size == 0) {
+        return MBEDTLS_ERR_ASN1_BUF_TOO_SMALL;
+    }
+
+    c = buf + size;
+
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+    if (mbedtls_pk_get_type(key) == MBEDTLS_PK_OPAQUE) {
+        opaque_key_type = pk_get_opaque_key_type(key);
+#if defined(MBEDTLS_RSA_C)
+        is_rsa_opaque = PSA_KEY_TYPE_IS_RSA(opaque_key_type);
+#endif /* MBEDTLS_RSA_C */
+#if defined(MBEDTLS_ECP_LIGHT)
+        is_ec_opaque = PSA_KEY_TYPE_IS_ECC(opaque_key_type);
+#endif /* MBEDTLS_ECP_LIGHT */
+    }
+#endif /* MBEDTLS_USE_PSA_CRYPTO */
+
+#if defined(MBEDTLS_RSA_C)
+    if ((mbedtls_pk_get_type(key) == MBEDTLS_PK_RSA) || is_rsa_opaque) {
+        return pk_write_rsa_der(&c, buf, key);
     } else
 #endif /* MBEDTLS_RSA_C */
 #if defined(MBEDTLS_ECP_LIGHT)
-    if (mbedtls_pk_get_type(key) == MBEDTLS_PK_ECKEY) {
-        size_t pub_len = 0, par_len = 0;
-
+    if ((mbedtls_pk_get_type(key) == MBEDTLS_PK_ECKEY) || is_ec_opaque) {
 #if defined(MBEDTLS_PK_HAVE_RFC8410_CURVES)
         if (mbedtls_pk_is_rfc8410(key)) {
             return pk_write_ec_rfc8410_der(&c, buf, key);
         }
-#endif
-
-        /*
-         * 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
-         *    }
-         */
-
-        /* publicKey */
-        MBEDTLS_ASN1_CHK_ADD(pub_len, pk_write_ec_pubkey(&c, buf, key));
-
-        if (c - buf < 1) {
-            return MBEDTLS_ERR_ASN1_BUF_TOO_SMALL;
-        }
-        *--c = 0;
-        pub_len += 1;
-
-        MBEDTLS_ASN1_CHK_ADD(pub_len, mbedtls_asn1_write_len(&c, buf, pub_len));
-        MBEDTLS_ASN1_CHK_ADD(pub_len, mbedtls_asn1_write_tag(&c, buf, MBEDTLS_ASN1_BIT_STRING));
-
-        MBEDTLS_ASN1_CHK_ADD(pub_len, mbedtls_asn1_write_len(&c, buf, pub_len));
-        MBEDTLS_ASN1_CHK_ADD(pub_len, mbedtls_asn1_write_tag(&c, buf,
-                                                             MBEDTLS_ASN1_CONTEXT_SPECIFIC |
-                                                             MBEDTLS_ASN1_CONSTRUCTED | 1));
-        len += pub_len;
-
-        /* parameters */
-        grp_id = mbedtls_pk_get_group_id(key);
-        MBEDTLS_ASN1_CHK_ADD(par_len, pk_write_ec_param(&c, buf, grp_id));
-
-        MBEDTLS_ASN1_CHK_ADD(par_len, mbedtls_asn1_write_len(&c, buf, par_len));
-        MBEDTLS_ASN1_CHK_ADD(par_len, mbedtls_asn1_write_tag(&c, buf,
-                                                             MBEDTLS_ASN1_CONTEXT_SPECIFIC |
-                                                             MBEDTLS_ASN1_CONSTRUCTED | 0));
-        len += par_len;
-
-        /* privateKey */
-        MBEDTLS_ASN1_CHK_ADD(len, pk_write_ec_private(&c, buf, key));
-
-        /* version */
-        MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_int(&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));
+#endif /* MBEDTLS_PK_HAVE_RFC8410_CURVES */
+        return pk_write_ec_der(&c, buf, key);
     } else
 #endif /* MBEDTLS_ECP_LIGHT */
     return MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE;
@@ -633,21 +781,50 @@
     unsigned char output_buf[PRV_DER_MAX_BYTES];
     const char *begin, *end;
     size_t olen = 0;
+#if defined(MBEDTLS_ECP_LIGHT)
+    int is_ec_opaque = 0;
+#if defined(MBEDTLS_PK_HAVE_RFC8410_CURVES)
+    int is_montgomery_opaque = 0;
+#endif /* MBEDTLS_PK_HAVE_RFC8410_CURVES */
+#endif /* MBEDTLS_ECP_LIGHT */
+#if defined(MBEDTLS_RSA_C)
+    int is_rsa_opaque = 0;
+#endif
 
     if ((ret = mbedtls_pk_write_key_der(key, output_buf, sizeof(output_buf))) < 0) {
         return ret;
     }
 
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+    if (mbedtls_pk_get_type(key) == MBEDTLS_PK_OPAQUE) {
+        psa_key_type_t opaque_key_type = pk_get_opaque_key_type(key);
+
 #if defined(MBEDTLS_RSA_C)
-    if (mbedtls_pk_get_type(key) == MBEDTLS_PK_RSA) {
+        is_rsa_opaque = PSA_KEY_TYPE_IS_RSA(opaque_key_type);
+#endif
+#if defined(MBEDTLS_ECP_LIGHT)
+        is_ec_opaque = PSA_KEY_TYPE_IS_ECC(opaque_key_type);
+#if defined(MBEDTLS_PK_HAVE_RFC8410_CURVES)
+        if (pk_get_opaque_ec_family(key) == PSA_ECC_FAMILY_MONTGOMERY) {
+            is_montgomery_opaque = 1;
+        }
+#endif /* MBEDTLS_PK_HAVE_RFC8410_CURVES */
+#endif /* MBEDTLS_ECP_LIGHT */
+    }
+#endif /* MBEDTLS_USE_PSA_CRYPTO */
+
+#if defined(MBEDTLS_RSA_C)
+    if ((mbedtls_pk_get_type(key) == MBEDTLS_PK_RSA) || is_rsa_opaque) {
         begin = PEM_BEGIN_PRIVATE_KEY_RSA;
         end = PEM_END_PRIVATE_KEY_RSA;
     } else
 #endif
 #if defined(MBEDTLS_ECP_LIGHT)
-    if (mbedtls_pk_get_type(key) == MBEDTLS_PK_ECKEY) {
+    if ((mbedtls_pk_get_type(key) == MBEDTLS_PK_ECKEY) || is_ec_opaque) {
 #if defined(MBEDTLS_PK_HAVE_RFC8410_CURVES)
-        if (mbedtls_pk_is_rfc8410(key)) {
+        if (is_montgomery_opaque ||
+            ((mbedtls_pk_get_type(key) == MBEDTLS_PK_ECKEY) &&
+             (mbedtls_pk_is_rfc8410(key)))) {
             begin = PEM_BEGIN_PRIVATE_KEY_PKCS8;
             end = PEM_END_PRIVATE_KEY_PKCS8;
         } else
diff --git a/library/ssl_tls13_client.c b/library/ssl_tls13_client.c
index e1d0c6c..e347853 100644
--- a/library/ssl_tls13_client.c
+++ b/library/ssl_tls13_client.c
@@ -1696,7 +1696,7 @@
                               cipher_suite, ciphersuite_info->name));
 
 #if defined(MBEDTLS_HAVE_TIME)
-    ssl->session_negotiate->start = time(NULL);
+    ssl->session_negotiate->start = mbedtls_time(NULL);
 #endif /* MBEDTLS_HAVE_TIME */
 
     /* ...
diff --git a/library/ssl_tls13_server.c b/library/ssl_tls13_server.c
index 33121af..dc3c2f0 100644
--- a/library/ssl_tls13_server.c
+++ b/library/ssl_tls13_server.c
@@ -1846,7 +1846,7 @@
                           MBEDTLS_SERVER_HELLO_RANDOM_LEN);
 
 #if defined(MBEDTLS_HAVE_TIME)
-    ssl->session_negotiate->start = time(NULL);
+    ssl->session_negotiate->start = mbedtls_time(NULL);
 #endif /* MBEDTLS_HAVE_TIME */
 
     return ret;
diff --git a/library/x509.c b/library/x509.c
index 5f6715a..8a44264 100644
--- a/library/x509.c
+++ b/library/x509.c
@@ -1215,9 +1215,9 @@
     mbedtls_asn1_sequence *cur = subject_alt_name;
 
     while (*p < end) {
-        mbedtls_x509_subject_alternative_name dummy_san_buf;
+        mbedtls_x509_subject_alternative_name tmp_san_name;
         mbedtls_x509_buf tmp_san_buf;
-        memset(&dummy_san_buf, 0, sizeof(dummy_san_buf));
+        memset(&tmp_san_name, 0, sizeof(tmp_san_name));
 
         tmp_san_buf.tag = **p;
         (*p)++;
@@ -1236,9 +1236,10 @@
         }
 
         /*
-         * Check that the SAN is structured correctly.
+         * Check that the SAN is structured correctly by parsing it.
+         * The SAN structure is discarded afterwards.
          */
-        ret = mbedtls_x509_parse_subject_alt_name(&tmp_san_buf, &dummy_san_buf);
+        ret = mbedtls_x509_parse_subject_alt_name(&tmp_san_buf, &tmp_san_name);
         /*
          * In case the extension is malformed, return an error,
          * and clear the allocated sequences.
@@ -1249,7 +1250,7 @@
             return ret;
         }
 
-        mbedtls_x509_free_subject_alt_name(&dummy_san_buf);
+        mbedtls_x509_free_subject_alt_name(&tmp_san_name);
         /* Allocate and assign next pointer */
         if (cur->buf.p != NULL) {
             if (cur->next != NULL) {
@@ -1439,7 +1440,7 @@
         break;
 
         /*
-         * RFC822 Name
+         * rfc822Name
          */
         case (MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_X509_SAN_RFC822_NAME):
         {
diff --git a/library/x509write_crt.c b/library/x509write_crt.c
index 70d7e93..274eb4b 100644
--- a/library/x509write_crt.c
+++ b/library/x509write_crt.c
@@ -31,10 +31,12 @@
 #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"
@@ -47,6 +49,16 @@
 
 #include "hash_info.h"
 
+#define CHECK_OVERFLOW_ADD(a, b) \
+    do                         \
+    {                           \
+        if (a > SIZE_MAX - (b)) \
+        { \
+            return MBEDTLS_ERR_X509_BAD_INPUT_DATA; \
+        }                            \
+        a += b; \
+    } while (0)
+
 void mbedtls_x509write_crt_init(mbedtls_x509write_cert *ctx)
 {
     memset(ctx, 0, sizeof(mbedtls_x509write_cert));
@@ -152,6 +164,137 @@
     return 0;
 }
 
+int mbedtls_x509write_crt_set_subject_alternative_name(mbedtls_x509write_cert *ctx,
+                                                       const mbedtls_x509_san_list *san_list)
+{
+    int ret = 0;
+    const mbedtls_x509_san_list *cur;
+    unsigned char *buf;
+    unsigned char *p;
+    size_t len;
+    size_t buflen = 0;
+
+    /* Determine the maximum size of the SubjectAltName list */
+    for (cur = san_list; cur != NULL; cur = cur->next) {
+        /* Calculate size of the required buffer */
+        switch (cur->node.type) {
+            case MBEDTLS_X509_SAN_DNS_NAME:
+            case MBEDTLS_X509_SAN_UNIFORM_RESOURCE_IDENTIFIER:
+            case MBEDTLS_X509_SAN_IP_ADDRESS:
+            case MBEDTLS_X509_SAN_RFC822_NAME:
+                /* length of value for each name entry,
+                 * maximum 4 bytes for the length field,
+                 * 1 byte for the tag/type.
+                 */
+                CHECK_OVERFLOW_ADD(buflen, cur->node.san.unstructured_name.len);
+                CHECK_OVERFLOW_ADD(buflen, 4 + 1);
+                break;
+            case MBEDTLS_X509_SAN_DIRECTORY_NAME:
+            {
+                const mbedtls_asn1_named_data *chunk = &cur->node.san.directory_name;
+                while (chunk != NULL) {
+                    // Max 4 bytes for length, +1 for tag,
+                    // additional 4 max for length, +1 for tag.
+                    // See x509_write_name for more information.
+                    CHECK_OVERFLOW_ADD(buflen, 4 + 1 + 4 + 1);
+                    CHECK_OVERFLOW_ADD(buflen, chunk->oid.len);
+                    CHECK_OVERFLOW_ADD(buflen, chunk->val.len);
+                    chunk = chunk->next;
+                }
+                CHECK_OVERFLOW_ADD(buflen, 4 + 1);
+                break;
+            }
+            default:
+                /* Not supported - return. */
+                return MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE;
+        }
+    }
+
+    /* Add the extra length field and tag */
+    CHECK_OVERFLOW_ADD(buflen, 4 + 1);
+
+    /* Allocate buffer */
+    buf = mbedtls_calloc(1, buflen);
+    if (buf == NULL) {
+        return MBEDTLS_ERR_ASN1_ALLOC_FAILED;
+    }
+    p = buf + buflen;
+
+    /* Write ASN.1-based structure */
+    cur = san_list;
+    len = 0;
+    while (cur != NULL) {
+        size_t single_san_len = 0;
+        switch (cur->node.type) {
+            case MBEDTLS_X509_SAN_DNS_NAME:
+            case MBEDTLS_X509_SAN_RFC822_NAME:
+            case MBEDTLS_X509_SAN_UNIFORM_RESOURCE_IDENTIFIER:
+            case MBEDTLS_X509_SAN_IP_ADDRESS:
+            {
+                const unsigned char *unstructured_name =
+                    (const unsigned char *) cur->node.san.unstructured_name.p;
+                size_t unstructured_name_len = cur->node.san.unstructured_name.len;
+
+                MBEDTLS_ASN1_CHK_CLEANUP_ADD(single_san_len,
+                                             mbedtls_asn1_write_raw_buffer(
+                                                 &p, buf,
+                                                 unstructured_name, unstructured_name_len));
+                MBEDTLS_ASN1_CHK_CLEANUP_ADD(single_san_len, mbedtls_asn1_write_len(
+                                                 &p, buf, unstructured_name_len));
+                MBEDTLS_ASN1_CHK_CLEANUP_ADD(single_san_len,
+                                             mbedtls_asn1_write_tag(
+                                                 &p, buf,
+                                                 MBEDTLS_ASN1_CONTEXT_SPECIFIC | cur->node.type));
+            }
+            break;
+            case MBEDTLS_X509_SAN_DIRECTORY_NAME:
+                MBEDTLS_ASN1_CHK_CLEANUP_ADD(single_san_len,
+                                             mbedtls_x509_write_names(&p, buf,
+                                                                      (mbedtls_asn1_named_data *) &
+                                                                      cur->node
+                                                                      .san.directory_name));
+                MBEDTLS_ASN1_CHK_CLEANUP_ADD(single_san_len,
+                                             mbedtls_asn1_write_len(&p, buf, single_san_len));
+                MBEDTLS_ASN1_CHK_CLEANUP_ADD(single_san_len,
+                                             mbedtls_asn1_write_tag(&p, buf,
+                                                                    MBEDTLS_ASN1_CONTEXT_SPECIFIC |
+                                                                    MBEDTLS_ASN1_CONSTRUCTED |
+                                                                    MBEDTLS_X509_SAN_DIRECTORY_NAME));
+                break;
+            default:
+                /* Error out on an unsupported SAN */
+                ret = MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE;
+                goto cleanup;
+        }
+        cur = cur->next;
+        /* check for overflow */
+        if (len > SIZE_MAX - single_san_len) {
+            ret = MBEDTLS_ERR_X509_BAD_INPUT_DATA;
+            goto cleanup;
+        }
+        len += single_san_len;
+    }
+
+    MBEDTLS_ASN1_CHK_CLEANUP_ADD(len, mbedtls_asn1_write_len(&p, buf, len));
+    MBEDTLS_ASN1_CHK_CLEANUP_ADD(len,
+                                 mbedtls_asn1_write_tag(&p, buf,
+                                                        MBEDTLS_ASN1_CONSTRUCTED |
+                                                        MBEDTLS_ASN1_SEQUENCE));
+
+    ret = mbedtls_x509write_crt_set_extension(
+        ctx,
+        MBEDTLS_OID_SUBJECT_ALT_NAME,
+        MBEDTLS_OID_SIZE(MBEDTLS_OID_SUBJECT_ALT_NAME),
+        0,
+        buf + buflen - len,
+        len);
+
+cleanup:
+    mbedtls_free(buf);
+    return ret;
+}
+
+
 int mbedtls_x509write_crt_set_extension(mbedtls_x509write_cert *ctx,
                                         const char *oid, size_t oid_len,
                                         int critical,
diff --git a/programs/x509/cert_req.c b/programs/x509/cert_req.c
index 1772f87..fe060f3 100644
--- a/programs/x509/cert_req.c
+++ b/programs/x509/cert_req.c
@@ -66,7 +66,7 @@
     "    output_file=%%s      default: cert.req\n"      \
     "    subject_name=%%s     default: CN=Cert,O=mbed TLS,C=UK\n"   \
     "    san=%%s              default: (none)\n"       \
-    "                        Comma-separated-list of values:\n"     \
+    "                        Semicolon-separated-list of values:\n"     \
     "                          DNS:value\n"            \
     "                          URI:value\n"            \
     "                          IP:value (Only IPv4 is supported)\n"             \
@@ -119,7 +119,7 @@
 static void ip_string_to_bytes(const char *str, uint8_t *bytes, int maxBytes)
 {
     for (int i = 0; i < maxBytes; i++) {
-        bytes[i] = (uint8_t) strtoul(str, NULL, 16);
+        bytes[i] = (uint8_t) strtoul(str, NULL, 10);
         str = strchr(str, '.');
         if (str == NULL || *str == '\0') {
             break;
diff --git a/programs/x509/cert_write.c b/programs/x509/cert_write.c
index 51b09f3..e4f8886 100644
--- a/programs/x509/cert_write.c
+++ b/programs/x509/cert_write.c
@@ -79,6 +79,7 @@
 #define DFL_NOT_AFTER           "20301231235959"
 #define DFL_SERIAL              "1"
 #define DFL_SERIAL_HEX          "1"
+#define DFL_EXT_SUBJECTALTNAME  ""
 #define DFL_SELFSIGN            0
 #define DFL_IS_CA               0
 #define DFL_MAX_PATHLEN         -1
@@ -134,6 +135,13 @@
     "    subject_identifier=%%s   default: 1\n"             \
     "                            Possible values: 0, 1\n"   \
     "                            (Considered for v3 only)\n" \
+    "    san=%%s                   default: (none)\n"       \
+    "                            Semicolon-separated-list of values:\n" \
+    "                             DNS:value\n"            \
+    "                             URI:value\n"            \
+    "                             RFC822:value\n"         \
+    "                             IP:value (Only IPv4 is supported)\n" \
+    "                             DN:list of comma separated key=value pairs\n" \
     "    authority_identifier=%%s default: 1\n"             \
     "                            Possible values: 0, 1\n"   \
     "                            (Considered for v3 only)\n" \
@@ -188,6 +196,7 @@
     const char *issuer_pwd;     /* password for the issuer key file     */
     const char *output_file;    /* where to store the constructed CRT   */
     const char *subject_name;   /* subject name for certificate         */
+    mbedtls_x509_san_list *san_list; /* subjectAltName for certificate  */
     const char *issuer_name;    /* issuer name for certificate          */
     const char *not_before;     /* validity period not before           */
     const char *not_after;      /* validity period not after            */
@@ -207,6 +216,18 @@
     int format;                 /* format                               */
 } opt;
 
+static void ip_string_to_bytes(const char *str, uint8_t *bytes, int maxBytes)
+{
+    for (int i = 0; i < maxBytes; i++) {
+        bytes[i] = (uint8_t) strtoul(str, NULL, 10);
+        str = strchr(str, '.');
+        if (str == NULL || *str == '\0') {
+            break;
+        }
+        str++;
+    }
+}
+
 int write_certificate(mbedtls_x509write_cert *crt, const char *output_file,
                       int (*f_rng)(void *, unsigned char *, size_t),
                       void *p_rng)
@@ -314,7 +335,9 @@
     mbedtls_entropy_context entropy;
     mbedtls_ctr_drbg_context ctr_drbg;
     const char *pers = "crt example app";
-
+    mbedtls_x509_san_list *cur, *prev;
+    mbedtls_asn1_named_data *ext_san_dirname = NULL;
+    uint8_t ip[4] = { 0 };
     /*
      * Set to sane values
      */
@@ -370,6 +393,7 @@
     opt.authority_identifier = DFL_AUTH_IDENT;
     opt.basic_constraints    = DFL_CONSTRAINTS;
     opt.format              = DFL_FORMAT;
+    opt.san_list            = NULL;
 
     for (i = 1; i < argc; i++) {
 
@@ -528,6 +552,92 @@
 
                 q = r;
             }
+        } else if (strcmp(p, "san") == 0) {
+            char *subtype_value;
+            prev = NULL;
+
+            while (q != NULL) {
+                char *semicolon;
+                r = q;
+
+                /* Find the first non-escaped ; occurrence and remove escaped ones */
+                do {
+                    if ((semicolon = strchr(r, ';')) != NULL) {
+                        if (*(semicolon-1) != '\\') {
+                            r = semicolon;
+                            break;
+                        }
+                        /* Remove the escape character */
+                        size_t size_left = strlen(semicolon);
+                        memmove(semicolon-1, semicolon, size_left);
+                        *(semicolon + size_left - 1) = '\0';
+                        /* r will now point at the character after the semicolon */
+                        r = semicolon;
+                    }
+
+                } while (semicolon != NULL);
+
+                if (semicolon != NULL) {
+                    *r++ = '\0';
+                } else {
+                    r = NULL;
+                }
+
+                cur = mbedtls_calloc(1, sizeof(mbedtls_x509_san_list));
+                if (cur == NULL) {
+                    mbedtls_printf("Not enough memory for subjectAltName list\n");
+                    goto usage;
+                }
+
+                cur->next = NULL;
+
+                if ((subtype_value = strchr(q, ':')) != NULL) {
+                    *subtype_value++ = '\0';
+                }
+                if (strcmp(q, "RFC822") == 0) {
+                    cur->node.type = MBEDTLS_X509_SAN_RFC822_NAME;
+                } else if (strcmp(q, "URI") == 0) {
+                    cur->node.type = MBEDTLS_X509_SAN_UNIFORM_RESOURCE_IDENTIFIER;
+                } else if (strcmp(q, "DNS") == 0) {
+                    cur->node.type = MBEDTLS_X509_SAN_DNS_NAME;
+                } else if (strcmp(q, "IP") == 0) {
+                    cur->node.type = MBEDTLS_X509_SAN_IP_ADDRESS;
+                    ip_string_to_bytes(subtype_value, ip, 4);
+                    cur->node.san.unstructured_name.p = (unsigned char *) ip;
+                    cur->node.san.unstructured_name.len = sizeof(ip);
+                } else if (strcmp(q, "DN") == 0) {
+                    cur->node.type = MBEDTLS_X509_SAN_DIRECTORY_NAME;
+                    if ((ret = mbedtls_x509_string_to_names(&ext_san_dirname,
+                                                            subtype_value)) != 0) {
+                        mbedtls_strerror(ret, buf, sizeof(buf));
+                        mbedtls_printf(
+                            " failed\n  !  mbedtls_x509_string_to_names "
+                            "returned -0x%04x - %s\n\n",
+                            (unsigned int) -ret, buf);
+                        goto exit;
+                    }
+                    cur->node.san.directory_name = *ext_san_dirname;
+                } else {
+                    mbedtls_free(cur);
+                    goto usage;
+                }
+
+                if (cur->node.type == MBEDTLS_X509_SAN_RFC822_NAME ||
+                    cur->node.type == MBEDTLS_X509_SAN_UNIFORM_RESOURCE_IDENTIFIER ||
+                    cur->node.type == MBEDTLS_X509_SAN_DNS_NAME) {
+                    cur->node.san.unstructured_name.p = (unsigned char *) subtype_value;
+                    cur->node.san.unstructured_name.len = strlen(subtype_value);
+                }
+
+                if (prev == NULL) {
+                    opt.san_list = cur;
+                } else {
+                    prev->next = cur;
+                }
+
+                prev = cur;
+                q = r;
+            }
         } else if (strcmp(p, "ns_cert_type") == 0) {
             while (q != NULL) {
                 if ((r = strchr(q, ',')) != NULL) {
@@ -833,6 +943,17 @@
         mbedtls_printf(" ok\n");
     }
 
+    if (opt.san_list != NULL) {
+        ret = mbedtls_x509write_crt_set_subject_alternative_name(&crt, opt.san_list);
+
+        if (ret != 0) {
+            mbedtls_printf(
+                " failed\n  !  mbedtls_x509write_crt_set_subject_alternative_name returned %d",
+                ret);
+            goto exit;
+        }
+    }
+
     if (opt.ext_key_usage) {
         mbedtls_printf("  . Adding the Extended Key Usage extension ...");
         fflush(stdout);
@@ -888,6 +1009,7 @@
 #if defined(MBEDTLS_X509_CSR_PARSE_C)
     mbedtls_x509_csr_free(&csr);
 #endif /* MBEDTLS_X509_CSR_PARSE_C */
+    mbedtls_asn1_free_named_data_list(&ext_san_dirname);
     mbedtls_x509_crt_free(&issuer_crt);
     mbedtls_x509write_crt_free(&crt);
     mbedtls_pk_free(&loaded_subject_key);
diff --git a/tests/data_files/Makefile b/tests/data_files/Makefile
index 3d2d5dc..070a8f7 100644
--- a/tests/data_files/Makefile
+++ b/tests/data_files/Makefile
@@ -1198,6 +1198,8 @@
 
 server1.crt: server1.key server1.req.sha256 $(test_ca_crt) $(test_ca_key_file_rsa)
 	$(MBEDTLS_CERT_WRITE) request_file=server1.req.sha256 issuer_crt=$(test_ca_crt) issuer_key=$(test_ca_key_file_rsa) issuer_pwd=$(test_ca_pwd_rsa) version=1 not_before=20190210144406 not_after=20290210144406 md=SHA1 version=3 output_file=$@
+server1.allSubjectAltNames.crt: server1.key server1.req.sha256 $(test_ca_crt) $(test_ca_key_file_rsa)	
+	$(MBEDTLS_CERT_WRITE) request_file=server1.req.sha256 issuer_crt=$(test_ca_crt) issuer_key=$(test_ca_key_file_rsa) issuer_pwd=$(test_ca_pwd_rsa) version=1 not_before=20190210144406 not_after=20290210144406 md=SHA1 version=3 output_file=$@ san=URI:http://pki.example.com\;IP:1.2.3.4\;DN:C=UK,O="Mbed TLS",CN="SubjectAltName test"\;DNS:example.com\;RFC822:mail@example.com
 server1.long_serial.crt: server1.key server1.req.sha256 $(test_ca_crt) $(test_ca_key_file_rsa)
 	echo "112233445566778899aabbccddeeff0011223344" > test-ca.server1.tmp.serial
 	$(OPENSSL) ca -in server1.req.sha256 -key PolarSSLTest -config test-ca.server1.test_serial.opensslconf -notext -batch -out $@
diff --git a/tests/data_files/server1.allSubjectAltNames.crt b/tests/data_files/server1.allSubjectAltNames.crt
new file mode 100644
index 0000000..13af873
--- /dev/null
+++ b/tests/data_files/server1.allSubjectAltNames.crt
@@ -0,0 +1,23 @@
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----
diff --git a/tests/scripts/all.sh b/tests/scripts/all.sh
index 4b22040..36d5fa4 100755
--- a/tests/scripts/all.sh
+++ b/tests/scripts/all.sh
@@ -2508,7 +2508,6 @@
     scripts/config.py -f include/psa/crypto_config.h unset PSA_WANT_KEY_TYPE_RSA_KEY_PAIR
     scripts/config.py -f include/psa/crypto_config.h unset PSA_WANT_KEY_TYPE_RSA_PUBLIC_KEY
     for ALG in $(sed -n 's/^#define \(PSA_WANT_ALG_RSA_[0-9A-Z_a-z]*\).*/\1/p' <"$CRYPTO_CONFIG_H"); do
-        echo $ALG
         scripts/config.py -f include/psa/crypto_config.h unset $ALG
     done
 
diff --git a/tests/suites/test_suite_pk.function b/tests/suites/test_suite_pk.function
index a5b50de..65b0c03 100644
--- a/tests/suites/test_suite_pk.function
+++ b/tests/suites/test_suite_pk.function
@@ -562,6 +562,9 @@
 void mbedtls_pk_check_pair(char *pub_file, char *prv_file, int ret)
 {
     mbedtls_pk_context pub, prv, alt;
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+    mbedtls_svc_key_id_t opaque_key_id = MBEDTLS_SVC_KEY_ID_INIT;
+#endif /* MBEDTLS_USE_PSA_CRYPTO */
 
     mbedtls_pk_init(&pub);
     mbedtls_pk_init(&prv);
@@ -575,7 +578,7 @@
     if (ret == MBEDTLS_ERR_ECP_BAD_INPUT_DATA) {
         ret = MBEDTLS_ERR_PK_BAD_INPUT_DATA;
     }
-#endif
+#endif /* MBEDTLS_USE_PSA_CRYPTO */
 
     TEST_ASSERT(mbedtls_pk_parse_public_keyfile(&pub, pub_file) == 0);
     TEST_ASSERT(mbedtls_pk_parse_keyfile(&prv, prv_file, NULL,
@@ -596,7 +599,20 @@
                     == ret);
     }
 #endif
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+    if (mbedtls_pk_get_type(&prv) == MBEDTLS_PK_ECKEY) {
+        TEST_EQUAL(mbedtls_pk_wrap_as_opaque(&prv, &opaque_key_id,
+                                             PSA_ALG_ANY_HASH,
+                                             PSA_KEY_USAGE_EXPORT, 0), 0);
+        TEST_EQUAL(mbedtls_pk_check_pair(&pub, &prv, mbedtls_test_rnd_std_rand,
+                                         NULL), ret);
+    }
+#endif
 
+exit:
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+    psa_destroy_key(opaque_key_id);
+#endif /* MBEDTLS_USE_PSA_CRYPTO */
     mbedtls_pk_free(&pub);
     mbedtls_pk_free(&prv);
     mbedtls_pk_free(&alt);
diff --git a/tests/suites/test_suite_pkwrite.function b/tests/suites/test_suite_pkwrite.function
index c148c8a..4820fbd 100644
--- a/tests/suites/test_suite_pkwrite.function
+++ b/tests/suites/test_suite_pkwrite.function
@@ -28,6 +28,43 @@
     }
 }
 
+static int pk_write_any_key(mbedtls_pk_context *pk, unsigned char **p,
+                            size_t *buf_len, int is_public_key, int is_der)
+{
+    int ret = 0;
+
+    if (is_der) {
+        if (is_public_key) {
+            ret = mbedtls_pk_write_pubkey_der(pk, *p, *buf_len);
+        } else {
+            ret = mbedtls_pk_write_key_der(pk, *p, *buf_len);
+        }
+        if (ret <= 0) {
+            return ret;
+        }
+
+        *p = *p + *buf_len - ret;
+        *buf_len = ret;
+    } else {
+#if defined(MBEDTLS_PEM_WRITE_C)
+        if (is_public_key) {
+            ret = mbedtls_pk_write_pubkey_pem(pk, *p, *buf_len);
+        } else {
+            ret = mbedtls_pk_write_key_pem(pk, *p, *buf_len);
+        }
+        if (ret != 0) {
+            return ret;
+        }
+
+        *buf_len = strlen((char *) *p) + 1; /* +1 takes the string terminator into account */
+#else
+        return MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE;
+#endif
+    }
+
+    return 0;
+}
+
 static void pk_write_check_common(char *key_file, int is_public_key, int is_der)
 {
     mbedtls_pk_context key;
@@ -35,7 +72,11 @@
     unsigned char *check_buf = NULL;
     unsigned char *start_buf;
     size_t buf_len, check_buf_len;
-    int ret;
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+    mbedtls_svc_key_id_t opaque_id = MBEDTLS_SVC_KEY_ID_INIT;
+#endif /* MBEDTLS_USE_PSA_CRYPTO */
+
+    USE_PSA_INIT();
 
     mbedtls_pk_init(&key);
     USE_PSA_INIT();
@@ -62,42 +103,39 @@
 
     if (is_public_key) {
         TEST_EQUAL(mbedtls_pk_parse_public_keyfile(&key, key_file), 0);
-        if (is_der) {
-            ret = mbedtls_pk_write_pubkey_der(&key, buf, check_buf_len);
-        } else {
-#if defined(MBEDTLS_PEM_WRITE_C)
-            ret = mbedtls_pk_write_pubkey_pem(&key, buf, check_buf_len);
-#else
-            ret = MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE;
-#endif
-        }
     } else {
         TEST_EQUAL(mbedtls_pk_parse_keyfile(&key, key_file, NULL,
                                             mbedtls_test_rnd_std_rand, NULL), 0);
-        if (is_der) {
-            ret = mbedtls_pk_write_key_der(&key, buf, check_buf_len);
-        } else {
-#if defined(MBEDTLS_PEM_WRITE_C)
-            ret = mbedtls_pk_write_key_pem(&key, buf, check_buf_len);
-#else
-            ret = MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE;
-#endif
-        }
     }
 
-    if (is_der) {
-        TEST_LE_U(1, ret);
-        buf_len = ret;
-        start_buf = buf + check_buf_len - buf_len;
-    } else {
-        TEST_EQUAL(ret, 0);
-        buf_len = strlen((char *) buf) + 1; /* +1 takes the string terminator into account */
-        start_buf = buf;
-    }
+    start_buf = buf;
+    buf_len = check_buf_len;
+    TEST_EQUAL(pk_write_any_key(&key, &start_buf, &buf_len, is_public_key,
+                                is_der), 0);
 
     ASSERT_COMPARE(start_buf, buf_len, check_buf, check_buf_len);
 
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+    /* Verify that pk_write works also for opaque private keys */
+    if (!is_public_key) {
+        memset(buf, 0, check_buf_len);
+        TEST_EQUAL(mbedtls_pk_wrap_as_opaque(&key, &opaque_id,
+                                             PSA_ALG_NONE,
+                                             PSA_KEY_USAGE_EXPORT,
+                                             PSA_ALG_NONE), 0);
+        start_buf = buf;
+        buf_len = check_buf_len;
+        TEST_EQUAL(pk_write_any_key(&key, &start_buf, &buf_len, is_public_key,
+                                    is_der), 0);
+
+        ASSERT_COMPARE(start_buf, buf_len, check_buf, check_buf_len);
+    }
+#endif /* MBEDTLS_USE_PSA_CRYPTO */
+
 exit:
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+    psa_destroy_key(opaque_id);
+#endif /* MBEDTLS_USE_PSA_CRYPTO */
     mbedtls_free(buf);
     mbedtls_free(check_buf);
     mbedtls_pk_free(&key);
diff --git a/tests/suites/test_suite_x509write.data b/tests/suites/test_suite_x509write.data
index e2198dc..4eeeacd 100644
--- a/tests/suites/test_suite_x509write.data
+++ b/tests/suites/test_suite_x509write.data
@@ -60,107 +60,111 @@
 
 Certificate write check Server1 SHA1
 depends_on:MBEDTLS_RSA_C:MBEDTLS_PKCS1_V15:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC:MBEDTLS_MD_CAN_MD5
-x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:1:-1:"data_files/server1.crt":0:0:"data_files/test-ca.crt"
+x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:1:-1:"data_files/server1.crt":0:0:"data_files/test-ca.crt":0
 
 Certificate write check Server1 SHA1, not before 1970
 depends_on:MBEDTLS_RSA_C:MBEDTLS_PKCS1_V15:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC:MBEDTLS_MD_CAN_MD5
-x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"19700210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:1:-1:"":0:0:"data_files/test-ca.crt"
+x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"19700210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:1:-1:"":0:0:"data_files/test-ca.crt":0
 
 Certificate write check Server1 SHA1, not after 2050
 depends_on:MBEDTLS_RSA_C:MBEDTLS_PKCS1_V15:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC:MBEDTLS_MD_CAN_MD5
-x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20500210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:1:-1:"":0:0:"data_files/test-ca.crt"
+x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20500210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:1:-1:"":0:0:"data_files/test-ca.crt":0
 
 Certificate write check Server1 SHA1, not before 1970, not after 2050
 depends_on:MBEDTLS_RSA_C:MBEDTLS_PKCS1_V15:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC:MBEDTLS_MD_CAN_MD5
-x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"19700210144406":"20500210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:1:-1:"":0:0:"data_files/test-ca.crt"
+x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"19700210144406":"20500210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:1:-1:"":0:0:"data_files/test-ca.crt":0
 
 Certificate write check Server1 SHA1, not before 2050, not after 2059
 depends_on:MBEDTLS_RSA_C:MBEDTLS_PKCS1_V15:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC:MBEDTLS_MD_CAN_MD5
-x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20500210144406":"20590210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:1:-1:"":0:0:"data_files/test-ca.crt"
+x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20500210144406":"20590210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:1:-1:"":0:0:"data_files/test-ca.crt":0
 
 Certificate write check Server1 SHA1, key_usage
 depends_on:MBEDTLS_RSA_C:MBEDTLS_PKCS1_V15:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC:MBEDTLS_MD_CAN_MD5
-x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:MBEDTLS_X509_KU_DIGITAL_SIGNATURE | MBEDTLS_X509_KU_NON_REPUDIATION | MBEDTLS_X509_KU_KEY_ENCIPHERMENT:1:"NULL":0:0:1:-1:"data_files/server1.key_usage.crt":0:0:"data_files/test-ca.crt"
+x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:MBEDTLS_X509_KU_DIGITAL_SIGNATURE | MBEDTLS_X509_KU_NON_REPUDIATION | MBEDTLS_X509_KU_KEY_ENCIPHERMENT:1:"NULL":0:0:1:-1:"data_files/server1.key_usage.crt":0:0:"data_files/test-ca.crt":0
 
 Certificate write check Server1 SHA1, one ext_key_usage
 depends_on:MBEDTLS_RSA_C:MBEDTLS_PKCS1_V15:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC:MBEDTLS_MD_CAN_MD5
-x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20110212144406":"20210212144406":MBEDTLS_MD_SHA1:0:0:"serverAuth":0:0:1:-1:"data_files/server1.key_ext_usage.crt":0:0:"data_files/test-ca.crt"
+x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20110212144406":"20210212144406":MBEDTLS_MD_SHA1:0:0:"serverAuth":0:0:1:-1:"data_files/server1.key_ext_usage.crt":0:0:"data_files/test-ca.crt":0
 
 Certificate write check Server1 SHA1, two ext_key_usages
 depends_on:MBEDTLS_RSA_C:MBEDTLS_PKCS1_V15:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC:MBEDTLS_MD_CAN_MD5
-x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20110212144406":"20210212144406":MBEDTLS_MD_SHA1:0:0:"codeSigning,timeStamping":0:0:1:-1:"data_files/server1.key_ext_usages.crt":0:0:"data_files/test-ca.crt"
+x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20110212144406":"20210212144406":MBEDTLS_MD_SHA1:0:0:"codeSigning,timeStamping":0:0:1:-1:"data_files/server1.key_ext_usages.crt":0:0:"data_files/test-ca.crt":0
 
 Certificate write check Server1 SHA1, ns_cert_type
 depends_on:MBEDTLS_RSA_C:MBEDTLS_PKCS1_V15:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC:MBEDTLS_MD_CAN_MD5
-x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":MBEDTLS_X509_NS_CERT_TYPE_SSL_SERVER:1:1:-1:"data_files/server1.cert_type.crt":0:0:"data_files/test-ca.crt"
+x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":MBEDTLS_X509_NS_CERT_TYPE_SSL_SERVER:1:1:-1:"data_files/server1.cert_type.crt":0:0:"data_files/test-ca.crt":0
 
 Certificate write check Server1 SHA1, version 1
 depends_on:MBEDTLS_RSA_C:MBEDTLS_PKCS1_V15:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC:MBEDTLS_MD_CAN_MD5
-x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:1:MBEDTLS_X509_CRT_VERSION_1:"data_files/server1.v1.crt":0:0:"data_files/test-ca.crt"
+x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:1:MBEDTLS_X509_CRT_VERSION_1:"data_files/server1.v1.crt":0:0:"data_files/test-ca.crt":0
 
 Certificate write check Server1 SHA1, CA
 depends_on:MBEDTLS_RSA_C:MBEDTLS_PKCS1_V15:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC:MBEDTLS_MD_CAN_MD5
-x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:1:-1:"data_files/server1.ca.crt":0:1:"data_files/test-ca.crt"
+x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:1:-1:"data_files/server1.ca.crt":0:1:"data_files/test-ca.crt":0
 
 Certificate write check Server1 SHA1, RSA_ALT
 depends_on:MBEDTLS_RSA_C:MBEDTLS_PKCS1_V15:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC:MBEDTLS_MD_CAN_MD5
-x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:0:-1:"data_files/server1.noauthid.crt":1:0:"data_files/test-ca.crt"
+x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:0:-1:"data_files/server1.noauthid.crt":1:0:"data_files/test-ca.crt":0
 
 Certificate write check Server1 SHA1, RSA_ALT, key_usage
 depends_on:MBEDTLS_RSA_C:MBEDTLS_PKCS1_V15:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC:MBEDTLS_MD_CAN_MD5
-x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:MBEDTLS_X509_KU_DIGITAL_SIGNATURE | MBEDTLS_X509_KU_NON_REPUDIATION | MBEDTLS_X509_KU_KEY_ENCIPHERMENT:1:"NULL":0:0:0:-1:"data_files/server1.key_usage_noauthid.crt":1:0:"data_files/test-ca.crt"
+x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:MBEDTLS_X509_KU_DIGITAL_SIGNATURE | MBEDTLS_X509_KU_NON_REPUDIATION | MBEDTLS_X509_KU_KEY_ENCIPHERMENT:1:"NULL":0:0:0:-1:"data_files/server1.key_usage_noauthid.crt":1:0:"data_files/test-ca.crt":0
 
 Certificate write check Server1 SHA1, RSA_ALT, ns_cert_type
 depends_on:MBEDTLS_RSA_C:MBEDTLS_PKCS1_V15:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC:MBEDTLS_MD_CAN_MD5
-x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":MBEDTLS_X509_NS_CERT_TYPE_SSL_SERVER:1:0:-1:"data_files/server1.cert_type_noauthid.crt":1:0:"data_files/test-ca.crt"
+x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":MBEDTLS_X509_NS_CERT_TYPE_SSL_SERVER:1:0:-1:"data_files/server1.cert_type_noauthid.crt":1:0:"data_files/test-ca.crt":0
 
 Certificate write check Server1 SHA1, RSA_ALT, version 1
 depends_on:MBEDTLS_RSA_C:MBEDTLS_PKCS1_V15:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC:MBEDTLS_MD_CAN_MD5
-x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:0:MBEDTLS_X509_CRT_VERSION_1:"data_files/server1.v1.crt":1:0:"data_files/test-ca.crt"
+x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:0:MBEDTLS_X509_CRT_VERSION_1:"data_files/server1.v1.crt":1:0:"data_files/test-ca.crt":0
 
 Certificate write check Server1 SHA1, RSA_ALT, CA
 depends_on:MBEDTLS_RSA_C:MBEDTLS_PKCS1_V15:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC:MBEDTLS_MD_CAN_MD5
-x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:0:-1:"data_files/server1.ca_noauthid.crt":1:1:"data_files/test-ca.crt"
+x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:0:-1:"data_files/server1.ca_noauthid.crt":1:1:"data_files/test-ca.crt":0
 
 Certificate write check Server1 SHA1, Opaque
 depends_on:MBEDTLS_RSA_C:MBEDTLS_PKCS1_V15:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC:MBEDTLS_MD_CAN_MD5:MBEDTLS_USE_PSA_CRYPTO
-x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:1:-1:"data_files/server1.crt":2:0:"data_files/test-ca.crt"
+x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:1:-1:"data_files/server1.crt":2:0:"data_files/test-ca.crt":0
 
 Certificate write check Server1 SHA1, Opaque, key_usage
 depends_on:MBEDTLS_RSA_C:MBEDTLS_PKCS1_V15:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC:MBEDTLS_MD_CAN_MD5:MBEDTLS_USE_PSA_CRYPTO
-x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:MBEDTLS_X509_KU_DIGITAL_SIGNATURE | MBEDTLS_X509_KU_NON_REPUDIATION | MBEDTLS_X509_KU_KEY_ENCIPHERMENT:1:"NULL":0:0:1:-1:"data_files/server1.key_usage.crt":2:0:"data_files/test-ca.crt"
+x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:MBEDTLS_X509_KU_DIGITAL_SIGNATURE | MBEDTLS_X509_KU_NON_REPUDIATION | MBEDTLS_X509_KU_KEY_ENCIPHERMENT:1:"NULL":0:0:1:-1:"data_files/server1.key_usage.crt":2:0:"data_files/test-ca.crt":0
 
 Certificate write check Server1 SHA1, Opaque, ns_cert_type
 depends_on:MBEDTLS_RSA_C:MBEDTLS_PKCS1_V15:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC:MBEDTLS_MD_CAN_MD5:MBEDTLS_USE_PSA_CRYPTO
-x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":MBEDTLS_X509_NS_CERT_TYPE_SSL_SERVER:1:1:-1:"data_files/server1.cert_type.crt":2:0:"data_files/test-ca.crt"
+x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":MBEDTLS_X509_NS_CERT_TYPE_SSL_SERVER:1:1:-1:"data_files/server1.cert_type.crt":2:0:"data_files/test-ca.crt":0
 
 Certificate write check Server1 SHA1, Opaque, version 1
 depends_on:MBEDTLS_RSA_C:MBEDTLS_PKCS1_V15:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC:MBEDTLS_MD_CAN_MD5:MBEDTLS_USE_PSA_CRYPTO
-x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:1:MBEDTLS_X509_CRT_VERSION_1:"data_files/server1.v1.crt":2:0:"data_files/test-ca.crt"
+x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:1:MBEDTLS_X509_CRT_VERSION_1:"data_files/server1.v1.crt":2:0:"data_files/test-ca.crt":0
 
 Certificate write check Server1 SHA1, Opaque, CA
 depends_on:MBEDTLS_RSA_C:MBEDTLS_PKCS1_V15:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC:MBEDTLS_MD_CAN_MD5:MBEDTLS_USE_PSA_CRYPTO
-x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:1:-1:"data_files/server1.ca.crt":2:1:"data_files/test-ca.crt"
+x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:1:-1:"data_files/server1.ca.crt":2:1:"data_files/test-ca.crt":0
 
 Certificate write check Server1 SHA1, Full length serial
 depends_on:MBEDTLS_RSA_C:MBEDTLS_PKCS1_V15:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC:MBEDTLS_MD_CAN_MD5
-x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"112233445566778899aabbccddeeff0011223344":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:1:-1:"data_files/server1.long_serial.crt":0:0:"data_files/test-ca.crt"
+x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"112233445566778899aabbccddeeff0011223344":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:1:-1:"data_files/server1.long_serial.crt":0:0:"data_files/test-ca.crt":0
 
 Certificate write check Server1 SHA1, Serial starting with 0x80
 depends_on:MBEDTLS_RSA_C:MBEDTLS_PKCS1_V15:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC:MBEDTLS_MD_CAN_MD5
-x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"8011223344":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:1:-1:"data_files/server1.80serial.crt":0:0:"data_files/test-ca.crt"
+x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"8011223344":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:1:-1:"data_files/server1.80serial.crt":0:0:"data_files/test-ca.crt":0
 
 Certificate write check Server1 SHA1, All 0xFF full length serial
 depends_on:MBEDTLS_RSA_C:MBEDTLS_PKCS1_V15:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CBC:MBEDTLS_MD_CAN_MD5
-x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"ffffffffffffffffffffffffffffffff":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:1:-1:"data_files/server1.long_serial_FF.crt":0:0:"data_files/test-ca.crt"
+x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"ffffffffffffffffffffffffffffffff":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:1:-1:"data_files/server1.long_serial_FF.crt":0:0:"data_files/test-ca.crt":0
 
 Certificate write check Server5 ECDSA
 depends_on:MBEDTLS_MD_CAN_SHA256:MBEDTLS_PK_CAN_ECDSA_SIGN:MBEDTLS_ECDSA_DETERMINISTIC:MBEDTLS_ECP_DP_SECP384R1_ENABLED:MBEDTLS_ECP_DP_SECP256R1_ENABLED
-x509_crt_check:"data_files/server5.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca2.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=Polarssl Test EC CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA256:0:0:"NULL":0:0:1:-1:"data_files/server5.crt":0:0:"data_files/test-ca2.crt"
+x509_crt_check:"data_files/server5.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca2.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=Polarssl Test EC CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA256:0:0:"NULL":0:0:1:-1:"data_files/server5.crt":0:0:"data_files/test-ca2.crt":0
 
 Certificate write check Server5 ECDSA, Opaque
 depends_on:MBEDTLS_MD_CAN_SHA256:MBEDTLS_PK_CAN_ECDSA_SIGN:MBEDTLS_ECDSA_DETERMINISTIC:MBEDTLS_ECP_DP_SECP384R1_ENABLED:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_USE_PSA_CRYPTO
-x509_crt_check:"data_files/server5.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca2.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=Polarssl Test EC CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA256:0:0:"NULL":0:0:1:-1:"":2:0:"data_files/test-ca2.crt"
+x509_crt_check:"data_files/server5.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca2.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=Polarssl Test EC CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA256:0:0:"NULL":0:0:1:-1:"":2:0:"data_files/test-ca2.crt":0
+
+Certificate write check Server1 SHA1, SubjectAltNames
+depends_on:MBEDTLS_RSA_C:MBEDTLS_PKCS1_V15:MBEDTLS_DES_C:MBEDTLS_CIPHER_MODE_CBC:MBEDTLS_MD_CAN_MD5:MBEDTLS_AES_C
+x509_crt_check:"data_files/server1.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=PolarSSL Test CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA1:0:0:"NULL":0:0:1:-1:"data_files/server1.allSubjectAltNames.crt":0:0:"data_files/test-ca.crt":1
 
 X509 String to Names #1
 mbedtls_x509_string_to_names:"C=NL,O=Offspark\\, Inc., OU=PolarSSL":"C=NL, O=Offspark\\, Inc., OU=PolarSSL":0
diff --git a/tests/suites/test_suite_x509write.function b/tests/suites/test_suite_x509write.function
index b08555c..d93c171 100644
--- a/tests/suites/test_suite_x509write.function
+++ b/tests/suites/test_suite_x509write.function
@@ -326,7 +326,7 @@
                     char *ext_key_usage,
                     int cert_type, int set_cert_type, int auth_ident,
                     int ver, char *cert_check_file, int pk_wrap, int is_ca,
-                    char *cert_verify_file)
+                    char *cert_verify_file, int set_subjectAltNames)
 {
     mbedtls_pk_context subject_key, issuer_key, issuer_key_alt;
     mbedtls_pk_context *key = &issuer_key;
@@ -348,6 +348,48 @@
     mbedtls_svc_key_id_t key_id = MBEDTLS_SVC_KEY_ID_INIT;
 #endif
     mbedtls_pk_type_t issuer_key_type;
+    mbedtls_x509_san_list san_ip;
+    mbedtls_x509_san_list san_dns;
+    mbedtls_x509_san_list san_uri;
+    mbedtls_x509_san_list san_mail;
+    mbedtls_x509_san_list san_dn;
+    mbedtls_asn1_named_data *ext_san_dirname = NULL;
+    const char san_ip_name[] = { 0x01, 0x02, 0x03, 0x04 };
+    const char *san_dns_name = "example.com";
+    const char *san_dn_name = "C=UK,O=Mbed TLS,CN=SubjectAltName test";
+    const char *san_mail_name = "mail@example.com";
+    const char *san_uri_name = "http://pki.example.com";
+    mbedtls_x509_san_list *san_list = NULL;
+
+    if (set_subjectAltNames) {
+        san_mail.node.type = MBEDTLS_X509_SAN_RFC822_NAME;
+        san_mail.node.san.unstructured_name.p = (unsigned char *) san_mail_name;
+        san_mail.node.san.unstructured_name.len = strlen(san_mail_name);
+        san_mail.next = NULL;
+
+        san_dns.node.type = MBEDTLS_X509_SAN_DNS_NAME;
+        san_dns.node.san.unstructured_name.p = (unsigned char *) san_dns_name;
+        san_dns.node.san.unstructured_name.len = strlen(san_dns_name);
+        san_dns.next = &san_mail;
+
+        san_dn.node.type = MBEDTLS_X509_SAN_DIRECTORY_NAME;
+        TEST_ASSERT(mbedtls_x509_string_to_names(&ext_san_dirname,
+                                                 san_dn_name) == 0);
+        san_dn.node.san.directory_name = *ext_san_dirname;
+        san_dn.next = &san_dns;
+
+        san_ip.node.type = MBEDTLS_X509_SAN_IP_ADDRESS;
+        san_ip.node.san.unstructured_name.p = (unsigned char *) san_ip_name;
+        san_ip.node.san.unstructured_name.len = sizeof(san_ip_name);
+        san_ip.next = &san_dn;
+
+        san_uri.node.type = MBEDTLS_X509_SAN_UNIFORM_RESOURCE_IDENTIFIER;
+        san_uri.node.san.unstructured_name.p = (unsigned char *) san_uri_name;
+        san_uri.node.san.unstructured_name.len = strlen(san_uri_name);
+        san_uri.next = &san_ip;
+
+        san_list = &san_uri;
+    }
 
     memset(&rnd_info, 0x2a, sizeof(mbedtls_test_rnd_pseudo_info));
 #if defined(MBEDTLS_TEST_DEPRECATED) && defined(MBEDTLS_BIGNUM_C)
@@ -465,6 +507,9 @@
         }
     }
 
+    if (set_subjectAltNames) {
+        TEST_ASSERT(mbedtls_x509write_crt_set_subject_alternative_name(&crt, san_list) == 0);
+    }
     ret = mbedtls_x509write_crt_pem(&crt, buf, sizeof(buf),
                                     mbedtls_test_rnd_pseudo_rand, &rnd_info);
     TEST_ASSERT(ret == 0);
@@ -573,6 +618,7 @@
     TEST_ASSERT(ret == MBEDTLS_ERR_ASN1_BUF_TOO_SMALL);
 
 exit:
+    mbedtls_asn1_free_named_data_list(&ext_san_dirname);
     mbedtls_x509write_crt_free(&crt);
     mbedtls_pk_free(&issuer_key_alt);
     mbedtls_pk_free(&subject_key);