diff --git a/BRANCHES.md b/BRANCHES.md
index d3bd75e..c085b16 100644
--- a/BRANCHES.md
+++ b/BRANCHES.md
@@ -106,6 +106,6 @@
 - [`development`](https://github.com/Mbed-TLS/mbedtls/)
 - [`mbedtls-2.28`](https://github.com/Mbed-TLS/mbedtls/tree/mbedtls-2.28)
  maintained until at least the end of 2024, see
-  <https://github.com/Mbed-TLS/mbedtls/releases/tag/v2.28.5>.
+  <https://github.com/Mbed-TLS/mbedtls/releases/tag/v2.28.6>.
 
 Users are urged to always use the latest version of a maintained branch.
diff --git a/CMakeLists.txt b/CMakeLists.txt
index cbe5748..36baa3b 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -377,7 +377,7 @@
     write_basic_package_version_file(
         "cmake/MbedTLSConfigVersion.cmake"
             COMPATIBILITY SameMajorVersion
-            VERSION 3.5.0)
+            VERSION 3.5.1)
 
     install(
         FILES "${CMAKE_CURRENT_BINARY_DIR}/cmake/MbedTLSConfig.cmake"
diff --git a/ChangeLog b/ChangeLog
index 4ba3164..28c45f7 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,15 @@
 Mbed TLS ChangeLog (Sorted per branch, date)
 
+= Mbed TLS 3.5.1 branch released 2023-11-06
+
+Changes
+   *  Mbed TLS is now released under a dual Apache-2.0 OR GPL-2.0-or-later
+      license. Users may choose which license they take the code under.
+
+Bugfix
+   * Fix accidental omission of MBEDTLS_TARGET_PREFIX in 3rdparty modules
+     in CMake.
+
 = Mbed TLS 3.5.0 branch released 2023-10-05
 
 API changes
diff --git a/ChangeLog.d/fix-3rdparty-target-prefix.txt b/ChangeLog.d/fix-3rdparty-target-prefix.txt
deleted file mode 100644
index db8ed07..0000000
--- a/ChangeLog.d/fix-3rdparty-target-prefix.txt
+++ /dev/null
@@ -1,3 +0,0 @@
-Bugfix
-   * Fix accidental omission of MBEDTLS_TARGET_PREFIX in 3rdparty modules
-     in CMake.
diff --git a/ChangeLog.d/fix-csr-parsing-with-critical-fields-fails.txt b/ChangeLog.d/fix-csr-parsing-with-critical-fields-fails.txt
new file mode 100644
index 0000000..5b15512
--- /dev/null
+++ b/ChangeLog.d/fix-csr-parsing-with-critical-fields-fails.txt
@@ -0,0 +1,6 @@
+Features
+   * Add new mbedtls_x509_csr_parse_der_with_ext_cb() routine which allows
+     parsing unsupported certificate extensions via user provided callback.
+
+Bugfix
+   * Fix parsing of CSRs with critical extensions.
diff --git a/ChangeLog.d/license.txt b/ChangeLog.d/license.txt
deleted file mode 100644
index 0b6bb1f..0000000
--- a/ChangeLog.d/license.txt
+++ /dev/null
@@ -1,3 +0,0 @@
-Changes
-   *  Mbed TLS is now released under a dual Apache-2.0 OR GPL-2.0-or-later
-      license. Users may choose which license they take the code under.
diff --git a/doxygen/input/doc_mainpage.h b/doxygen/input/doc_mainpage.h
index f465a45..c391c59 100644
--- a/doxygen/input/doc_mainpage.h
+++ b/doxygen/input/doc_mainpage.h
@@ -10,7 +10,7 @@
  */
 
 /**
- * @mainpage Mbed TLS v3.5.0 API Documentation
+ * @mainpage Mbed TLS v3.5.1 API Documentation
  *
  * This documentation describes the internal structure of Mbed TLS.  It was
  * automatically generated from specially formatted comment blocks in
diff --git a/doxygen/mbedtls.doxyfile b/doxygen/mbedtls.doxyfile
index 98b2d79..89048f2 100644
--- a/doxygen/mbedtls.doxyfile
+++ b/doxygen/mbedtls.doxyfile
@@ -1,4 +1,4 @@
-PROJECT_NAME           = "Mbed TLS v3.5.0"
+PROJECT_NAME           = "Mbed TLS v3.5.1"
 OUTPUT_DIRECTORY       = ../apidoc/
 FULL_PATH_NAMES        = NO
 OPTIMIZE_OUTPUT_FOR_C  = YES
diff --git a/include/mbedtls/build_info.h b/include/mbedtls/build_info.h
index 2c3d438..44ecacf 100644
--- a/include/mbedtls/build_info.h
+++ b/include/mbedtls/build_info.h
@@ -26,16 +26,16 @@
  */
 #define MBEDTLS_VERSION_MAJOR  3
 #define MBEDTLS_VERSION_MINOR  5
-#define MBEDTLS_VERSION_PATCH  0
+#define MBEDTLS_VERSION_PATCH  1
 
 /**
  * The single version number has the following structure:
  *    MMNNPP00
  *    Major version | Minor version | Patch version
  */
-#define MBEDTLS_VERSION_NUMBER         0x03050000
-#define MBEDTLS_VERSION_STRING         "3.5.0"
-#define MBEDTLS_VERSION_STRING_FULL    "Mbed TLS 3.5.0"
+#define MBEDTLS_VERSION_NUMBER         0x03050100
+#define MBEDTLS_VERSION_STRING         "3.5.1"
+#define MBEDTLS_VERSION_STRING_FULL    "Mbed TLS 3.5.1"
 
 /* Macros for build-time platform detection */
 
diff --git a/include/mbedtls/mbedtls_config.h b/include/mbedtls/mbedtls_config.h
index 6a940d4..542b76d 100644
--- a/include/mbedtls/mbedtls_config.h
+++ b/include/mbedtls/mbedtls_config.h
@@ -742,6 +742,9 @@
  * contexts and therefore is a compatibility break for applications that access
  * fields of a mbedtls_ecdh_context structure directly. See also
  * MBEDTLS_ECDH_LEGACY_CONTEXT in include/mbedtls/ecdh.h.
+ *
+ * The Everest code is provided under the Apache 2.0 license only; therefore enabling this
+ * option is not compatible with taking the library under the GPL v2.0-or-later license.
  */
 //#define MBEDTLS_ECDH_VARIANT_EVEREST_ENABLED
 
diff --git a/include/mbedtls/x509_csr.h b/include/mbedtls/x509_csr.h
index e54010b..8c31c09 100644
--- a/include/mbedtls/x509_csr.h
+++ b/include/mbedtls/x509_csr.h
@@ -75,7 +75,9 @@
 /**
  * \brief          Load a Certificate Signing Request (CSR) in DER format
  *
- * \note           CSR attributes (if any) are currently silently ignored.
+ * \note           Any unsupported requested extensions are silently
+ *                 ignored, unless the critical flag is set, in which case
+ *                 the CSR is rejected.
  *
  * \note           If #MBEDTLS_USE_PSA_CRYPTO is enabled, the PSA crypto
  *                 subsystem must have been initialized by calling
@@ -91,6 +93,67 @@
                                const unsigned char *buf, size_t buflen);
 
 /**
+ * \brief          The type of certificate extension callbacks.
+ *
+ *                 Callbacks of this type are passed to and used by the
+ *                 mbedtls_x509_csr_parse_der_with_ext_cb() routine when
+ *                 it encounters either an unsupported extension.
+ *                 Future versions of the library may invoke the callback
+ *                 in other cases, if and when the need arises.
+ *
+ * \param p_ctx    An opaque context passed to the callback.
+ * \param csr      The CSR being parsed.
+ * \param oid      The OID of the extension.
+ * \param critical Whether the extension is critical.
+ * \param p        Pointer to the start of the extension value
+ *                 (the content of the OCTET STRING).
+ * \param end      End of extension value.
+ *
+ * \note           The callback must fail and return a negative error code
+ *                 if it can not parse or does not support the extension.
+ *                 When the callback fails to parse a critical extension
+ *                 mbedtls_x509_csr_parse_der_with_ext_cb() also fails.
+ *                 When the callback fails to parse a non critical extension
+ *                 mbedtls_x509_csr_parse_der_with_ext_cb() simply skips
+ *                 the extension and continues parsing.
+ *
+ * \return         \c 0 on success.
+ * \return         A negative error code on failure.
+ */
+typedef int (*mbedtls_x509_csr_ext_cb_t)(void *p_ctx,
+                                         mbedtls_x509_csr const *csr,
+                                         mbedtls_x509_buf const *oid,
+                                         int critical,
+                                         const unsigned char *p,
+                                         const unsigned char *end);
+
+/**
+ * \brief          Load a Certificate Signing Request (CSR) in DER format
+ *
+ * \note           Any unsupported requested extensions are silently
+ *                 ignored, unless the critical flag is set, in which case
+ *                 the result of the callback function decides whether
+ *                 CSR is rejected.
+ *
+ * \note           If #MBEDTLS_USE_PSA_CRYPTO is enabled, the PSA crypto
+ *                 subsystem must have been initialized by calling
+ *                 psa_crypto_init() before calling this function.
+ *
+ * \param csr      CSR context to fill
+ * \param buf      buffer holding the CRL data
+ * \param buflen   size of the buffer
+ * \param cb       A callback invoked for every unsupported certificate
+ *                 extension.
+ * \param p_ctx    An opaque context passed to the callback.
+ *
+ * \return         0 if successful, or a specific X509 error code
+ */
+int mbedtls_x509_csr_parse_der_with_ext_cb(mbedtls_x509_csr *csr,
+                                           const unsigned char *buf, size_t buflen,
+                                           mbedtls_x509_csr_ext_cb_t cb,
+                                           void *p_ctx);
+
+/**
  * \brief          Load a Certificate Signing Request (CSR), DER or PEM format
  *
  * \note           See notes for \c mbedtls_x509_csr_parse_der()
diff --git a/library/CMakeLists.txt b/library/CMakeLists.txt
index 6a4ce51..eeda06a 100644
--- a/library/CMakeLists.txt
+++ b/library/CMakeLists.txt
@@ -296,7 +296,7 @@
 if(USE_SHARED_MBEDTLS_LIBRARY)
     set(CMAKE_LIBRARY_PATH ${CMAKE_CURRENT_BINARY_DIR})
     add_library(${mbedcrypto_target} SHARED ${src_crypto})
-    set_target_properties(${mbedcrypto_target} PROPERTIES VERSION 3.5.0 SOVERSION 15)
+    set_target_properties(${mbedcrypto_target} PROPERTIES VERSION 3.5.1 SOVERSION 15)
     target_link_libraries(${mbedcrypto_target} PUBLIC ${libs})
 
     if(TARGET ${everest_target})
@@ -308,11 +308,11 @@
     endif()
 
     add_library(${mbedx509_target} SHARED ${src_x509})
-    set_target_properties(${mbedx509_target} PROPERTIES VERSION 3.5.0 SOVERSION 6)
+    set_target_properties(${mbedx509_target} PROPERTIES VERSION 3.5.1 SOVERSION 6)
     target_link_libraries(${mbedx509_target} PUBLIC ${libs} ${mbedcrypto_target})
 
     add_library(${mbedtls_target} SHARED ${src_tls})
-    set_target_properties(${mbedtls_target} PROPERTIES VERSION 3.5.0 SOVERSION 20)
+    set_target_properties(${mbedtls_target} PROPERTIES VERSION 3.5.1 SOVERSION 20)
     target_link_libraries(${mbedtls_target} PUBLIC ${libs} ${mbedx509_target})
 endif(USE_SHARED_MBEDTLS_LIBRARY)
 
diff --git a/library/ssl_misc.h b/library/ssl_misc.h
index 7458330..bde55b6 100644
--- a/library/ssl_misc.h
+++ b/library/ssl_misc.h
@@ -2793,6 +2793,26 @@
            (flags & MBEDTLS_SSL_TLS1_3_TICKET_FLAGS_MASK);
 }
 
+static inline unsigned int mbedtls_ssl_session_check_ticket_flags(
+    mbedtls_ssl_session *session, unsigned int flags)
+{
+    return mbedtls_ssl_session_get_ticket_flags(session, flags) == 0;
+}
+
+static inline unsigned int mbedtls_ssl_session_ticket_allow_psk(
+    mbedtls_ssl_session *session)
+{
+    return !mbedtls_ssl_session_check_ticket_flags(session,
+                                                   MBEDTLS_SSL_TLS1_3_TICKET_ALLOW_PSK_RESUMPTION);
+}
+
+static inline unsigned int mbedtls_ssl_session_ticket_allow_psk_ephemeral(
+    mbedtls_ssl_session *session)
+{
+    return !mbedtls_ssl_session_check_ticket_flags(session,
+                                                   MBEDTLS_SSL_TLS1_3_TICKET_ALLOW_PSK_EPHEMERAL_RESUMPTION);
+}
+
 static inline void mbedtls_ssl_session_set_ticket_flags(
     mbedtls_ssl_session *session, unsigned int flags)
 {
diff --git a/library/ssl_tls13_client.c b/library/ssl_tls13_client.c
index 97ae51c..eac6326 100644
--- a/library/ssl_tls13_client.c
+++ b/library/ssl_tls13_client.c
@@ -1892,36 +1892,6 @@
             ret = MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE;
             goto cleanup;
     }
-#if defined(MBEDTLS_SSL_EARLY_DATA)
-    if (handshake->received_extensions & MBEDTLS_SSL_EXT_MASK(EARLY_DATA) &&
-        (handshake->selected_identity != 0 ||
-         handshake->ciphersuite_info->id !=
-         ssl->session_negotiate->ciphersuite)) {
-        /* RFC8446 4.2.11
-         * If the server supplies an "early_data" extension, the
-         * client MUST verify that the server's selected_identity
-         * is 0. If any other value is returned, the client MUST
-         * abort the handshake with an "illegal_parameter" alert.
-         *
-         * RFC 8446 4.2.10
-         * In order to accept early data, the server MUST have accepted a PSK
-         * cipher suite and selected the first key offered in the client's
-         * "pre_shared_key" extension. In addition, it MUST verify that the
-         * following values are the same as those associated with the
-         * selected PSK:
-         * - The TLS version number
-         * - The selected cipher suite
-         * - The selected ALPN [RFC7301] protocol, if any
-         *
-         * We check here that when early data is involved the server
-         * selected the cipher suite associated to the pre-shared key
-         * as it must have.
-         */
-        MBEDTLS_SSL_PEND_FATAL_ALERT(MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER,
-                                     MBEDTLS_ERR_SSL_ILLEGAL_PARAMETER);
-        return MBEDTLS_ERR_SSL_ILLEGAL_PARAMETER;
-    }
-#endif
 
     if (!mbedtls_ssl_conf_tls13_check_kex_modes(
             ssl, handshake->key_exchange_mode)) {
@@ -2197,6 +2167,9 @@
     int ret;
     unsigned char *buf;
     size_t buf_len;
+#if defined(MBEDTLS_SSL_EARLY_DATA)
+    mbedtls_ssl_handshake_params *handshake = ssl->handshake;
+#endif
 
     MBEDTLS_SSL_DEBUG_MSG(2, ("=> parse encrypted extensions"));
 
@@ -2209,8 +2182,37 @@
         ssl_tls13_parse_encrypted_extensions(ssl, buf, buf + buf_len));
 
 #if defined(MBEDTLS_SSL_EARLY_DATA)
-    if (ssl->handshake->received_extensions &
-        MBEDTLS_SSL_EXT_MASK(EARLY_DATA)) {
+    if (handshake->received_extensions & MBEDTLS_SSL_EXT_MASK(EARLY_DATA)) {
+        /* RFC8446 4.2.11
+         * If the server supplies an "early_data" extension, the
+         * client MUST verify that the server's selected_identity
+         * is 0. If any other value is returned, the client MUST
+         * abort the handshake with an "illegal_parameter" alert.
+         *
+         * RFC 8446 4.2.10
+         * In order to accept early data, the server MUST have accepted a PSK
+         * cipher suite and selected the first key offered in the client's
+         * "pre_shared_key" extension. In addition, it MUST verify that the
+         * following values are the same as those associated with the
+         * selected PSK:
+         * - The TLS version number
+         * - The selected cipher suite
+         * - The selected ALPN [RFC7301] protocol, if any
+         *
+         * We check here that when early data is involved the server
+         * selected the cipher suite associated to the pre-shared key
+         * as it must have.
+         */
+        if (handshake->selected_identity != 0 ||
+            handshake->ciphersuite_info->id !=
+            ssl->session_negotiate->ciphersuite) {
+
+            MBEDTLS_SSL_PEND_FATAL_ALERT(
+                MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER,
+                MBEDTLS_ERR_SSL_ILLEGAL_PARAMETER);
+            return MBEDTLS_ERR_SSL_ILLEGAL_PARAMETER;
+        }
+
         ssl->early_data_status = MBEDTLS_SSL_EARLY_DATA_STATUS_ACCEPTED;
     }
 #endif
diff --git a/library/ssl_tls13_server.c b/library/ssl_tls13_server.c
index 815c0a9..061dcf7 100644
--- a/library/ssl_tls13_server.c
+++ b/library/ssl_tls13_server.c
@@ -94,6 +94,10 @@
 #define SSL_TLS1_3_OFFERED_PSK_MATCH       0
 
 #if defined(MBEDTLS_SSL_SESSION_TICKETS)
+MBEDTLS_CHECK_RETURN_CRITICAL
+static int ssl_tls13_check_psk_key_exchange(mbedtls_ssl_context *ssl);
+MBEDTLS_CHECK_RETURN_CRITICAL
+static int ssl_tls13_check_psk_ephemeral_key_exchange(mbedtls_ssl_context *ssl);
 
 MBEDTLS_CHECK_RETURN_CRITICAL
 static int ssl_tls13_offered_psks_check_identity_match_ticket(
@@ -105,6 +109,7 @@
 {
     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
     unsigned char *ticket_buffer;
+    unsigned int key_exchanges;
 #if defined(MBEDTLS_HAVE_TIME)
     mbedtls_time_t now;
     uint64_t age_in_s;
@@ -147,6 +152,12 @@
     /* We delete the temporary buffer */
     mbedtls_free(ticket_buffer);
 
+    if (ret == 0 && session->tls_version != MBEDTLS_SSL_VERSION_TLS1_3) {
+        MBEDTLS_SSL_DEBUG_MSG(3, ("Ticket TLS version is not 1.3."));
+        /* TODO: Define new return value for this case. */
+        ret = MBEDTLS_ERR_SSL_BAD_PROTOCOL_VERSION;
+    }
+
     if (ret != 0) {
         goto exit;
     }
@@ -160,13 +171,19 @@
      * We regard the ticket with incompatible key exchange modes as not match.
      */
     ret = MBEDTLS_ERR_ERROR_GENERIC_ERROR;
-    MBEDTLS_SSL_PRINT_TICKET_FLAGS(4,
-                                   session->ticket_flags);
-    if (mbedtls_ssl_tls13_check_kex_modes(
-            ssl,
-            mbedtls_ssl_session_get_ticket_flags(
-                session,
-                MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_ALL))) {
+    MBEDTLS_SSL_PRINT_TICKET_FLAGS(4, session->ticket_flags);
+
+    key_exchanges = 0;
+    if (mbedtls_ssl_session_ticket_allow_psk_ephemeral(session) &&
+        ssl_tls13_check_psk_ephemeral_key_exchange(ssl)) {
+        key_exchanges |= MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL;
+    }
+    if (mbedtls_ssl_session_ticket_allow_psk(session) &&
+        ssl_tls13_check_psk_key_exchange(ssl)) {
+        key_exchanges |= MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK;
+    }
+
+    if (key_exchanges == 0) {
         MBEDTLS_SSL_DEBUG_MSG(3, ("No suitable key exchange mode"));
         goto exit;
     }
@@ -979,6 +996,26 @@
 }
 #endif /* MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL_ENABLED */
 
+#if defined(MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_SOME_PSK_ENABLED)
+MBEDTLS_CHECK_RETURN_CRITICAL
+static int ssl_tls13_ticket_permission_check(mbedtls_ssl_context *ssl,
+                                             unsigned int kex_mode)
+{
+#if defined(MBEDTLS_SSL_SESSION_TICKETS)
+    if (ssl->handshake->resume) {
+        if (mbedtls_ssl_session_check_ticket_flags(
+                ssl->session_negotiate, kex_mode)) {
+            return 0;
+        }
+    }
+#else
+    ((void) ssl);
+    ((void) kex_mode);
+#endif
+    return 1;
+}
+#endif /* MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_SOME_PSK_ENABLED */
+
 MBEDTLS_CHECK_RETURN_CRITICAL
 static int ssl_tls13_check_ephemeral_key_exchange(mbedtls_ssl_context *ssl)
 {
@@ -995,7 +1032,9 @@
 static int ssl_tls13_check_psk_key_exchange(mbedtls_ssl_context *ssl)
 {
 #if defined(MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_ENABLED)
-    return mbedtls_ssl_conf_tls13_psk_enabled(ssl) &&
+    return ssl_tls13_ticket_permission_check(
+        ssl, MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK) &&
+           mbedtls_ssl_conf_tls13_psk_enabled(ssl) &&
            mbedtls_ssl_tls13_psk_enabled(ssl) &&
            ssl_tls13_client_hello_has_exts_for_psk_key_exchange(ssl);
 #else
@@ -1008,7 +1047,9 @@
 static int ssl_tls13_check_psk_ephemeral_key_exchange(mbedtls_ssl_context *ssl)
 {
 #if defined(MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL_ENABLED)
-    return mbedtls_ssl_conf_tls13_psk_ephemeral_enabled(ssl) &&
+    return ssl_tls13_ticket_permission_check(
+        ssl, MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL) &&
+           mbedtls_ssl_conf_tls13_psk_ephemeral_enabled(ssl) &&
            mbedtls_ssl_tls13_psk_ephemeral_enabled(ssl) &&
            ssl_tls13_client_hello_has_exts_for_psk_ephemeral_key_exchange(ssl);
 #else
@@ -1691,9 +1732,8 @@
      * - The content up to but excluding the PSK extension, if present.
      */
     /* If we've settled on a PSK-based exchange, parse PSK identity ext */
-    if (mbedtls_ssl_tls13_some_psk_enabled(ssl) &&
-        mbedtls_ssl_conf_tls13_some_psk_enabled(ssl) &&
-        (handshake->received_extensions & MBEDTLS_SSL_EXT_MASK(PRE_SHARED_KEY))) {
+    if (ssl_tls13_check_psk_key_exchange(ssl) ||
+        ssl_tls13_check_psk_ephemeral_key_exchange(ssl)) {
         ret = handshake->update_checksum(ssl, buf,
                                          pre_shared_key_ext - buf);
         if (0 != ret) {
@@ -1750,9 +1790,59 @@
         return;
     }
 
-    /* We do not accept early data for the time being */
     ssl->early_data_status = MBEDTLS_SSL_EARLY_DATA_STATUS_REJECTED;
 
+    if (ssl->conf->early_data_enabled == MBEDTLS_SSL_EARLY_DATA_DISABLED) {
+        MBEDTLS_SSL_DEBUG_MSG(
+            1,
+            ("EarlyData: rejected, feature disabled in server configuration."));
+        return;
+    }
+
+    if (!handshake->resume) {
+        /* We currently support early data only in the case of PSKs established
+           via a NewSessionTicket message thus in the case of a session
+           resumption. */
+        MBEDTLS_SSL_DEBUG_MSG(
+            1, ("EarlyData: rejected, not a session resumption."));
+        return;
+    }
+
+    /* RFC 8446 4.2.10
+     *
+     * In order to accept early data, the server MUST have accepted a PSK cipher
+     * suite and selected the first key offered in the client's "pre_shared_key"
+     * extension. In addition, it MUST verify that the following values are the
+     * same as those associated with the selected PSK:
+     * - The TLS version number
+     * - The selected cipher suite
+     * - The selected ALPN [RFC7301] protocol, if any
+     *
+     * NOTE:
+     *  - The TLS version number is checked in
+     *    ssl_tls13_offered_psks_check_identity_match_ticket().
+     *  - ALPN is not checked for the time being (TODO).
+     */
+
+    if (handshake->selected_identity != 0) {
+        MBEDTLS_SSL_DEBUG_MSG(
+            1, ("EarlyData: rejected, the selected key in "
+                "`pre_shared_key` is not the first one."));
+        return;
+    }
+
+    if (handshake->ciphersuite_info->id !=
+        ssl->session_negotiate->ciphersuite) {
+        MBEDTLS_SSL_DEBUG_MSG(
+            1, ("EarlyData: rejected, the selected ciphersuite is not the one "
+                "of the selected pre-shared key."));
+        return;
+
+    }
+
+
+    ssl->early_data_status = MBEDTLS_SSL_EARLY_DATA_STATUS_ACCEPTED;
+
 }
 #endif /* MBEDTLS_SSL_EARLY_DATA */
 
@@ -2412,6 +2502,16 @@
     p += output_len;
 #endif /* MBEDTLS_SSL_ALPN */
 
+#if defined(MBEDTLS_SSL_EARLY_DATA)
+    if (ssl->early_data_status == MBEDTLS_SSL_EARLY_DATA_STATUS_ACCEPTED) {
+        ret = mbedtls_ssl_tls13_write_early_data_ext(ssl, p, end, &output_len);
+        if (ret != 0) {
+            return ret;
+        }
+        p += output_len;
+    }
+#endif /* MBEDTLS_SSL_EARLY_DATA */
+
     extensions_len = (p - p_extensions_len) - 2;
     MBEDTLS_PUT_UINT16_BE(extensions_len, p_extensions_len, 0);
 
diff --git a/library/x509_csr.c b/library/x509_csr.c
index b48b3a4..a293ec0 100644
--- a/library/x509_csr.c
+++ b/library/x509_csr.c
@@ -61,13 +61,17 @@
  * Parse CSR extension requests in DER format
  */
 static int x509_csr_parse_extensions(mbedtls_x509_csr *csr,
-                                     unsigned char **p, const unsigned char *end)
+                                     unsigned char **p, const unsigned char *end,
+                                     mbedtls_x509_csr_ext_cb_t cb,
+                                     void *p_ctx)
 {
-    int ret;
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
     size_t len;
-    unsigned char *end_ext_data;
+    unsigned char *end_ext_data, *end_ext_octet;
+
     while (*p < end) {
         mbedtls_x509_buf extn_oid = { 0, 0, NULL };
+        int is_critical = 0; /* DEFAULT FALSE */
         int ext_type = 0;
 
         /* Read sequence tag */
@@ -88,13 +92,21 @@
         extn_oid.p = *p;
         *p += extn_oid.len;
 
+        /* Get optional critical */
+        if ((ret = mbedtls_asn1_get_bool(p, end_ext_data, &is_critical)) != 0 &&
+            (ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG)) {
+            return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
+        }
+
         /* Data should be octet string type */
         if ((ret = mbedtls_asn1_get_tag(p, end_ext_data, &len,
                                         MBEDTLS_ASN1_OCTET_STRING)) != 0) {
             return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
         }
 
-        if (*p + len != end_ext_data) {
+        end_ext_octet = *p + len;
+
+        if (end_ext_octet != end_ext_data) {
             return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
                                      MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
         }
@@ -104,44 +116,72 @@
          */
         ret = mbedtls_oid_get_x509_ext_type(&extn_oid, &ext_type);
 
-        if (ret == 0) {
-            /* Forbid repeated extensions */
-            if ((csr->ext_types & ext_type) != 0) {
+        if (ret != 0) {
+            /* Give the callback (if any) a chance to handle the extension */
+            if (cb != NULL) {
+                ret = cb(p_ctx, csr, &extn_oid, is_critical, *p, end_ext_octet);
+                if (ret != 0 && is_critical) {
+                    return ret;
+                }
+                *p = end_ext_octet;
+                continue;
+            }
+
+            /* No parser found, skip extension */
+            *p = end_ext_octet;
+
+            if (is_critical) {
+                /* Data is marked as critical: fail */
                 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
-                                         MBEDTLS_ERR_ASN1_INVALID_DATA);
+                                         MBEDTLS_ERR_ASN1_UNEXPECTED_TAG);
             }
-
-            csr->ext_types |= ext_type;
-
-            switch (ext_type) {
-                case MBEDTLS_X509_EXT_KEY_USAGE:
-                    /* Parse key usage */
-                    if ((ret = mbedtls_x509_get_key_usage(p, end_ext_data,
-                                                          &csr->key_usage)) != 0) {
-                        return ret;
-                    }
-                    break;
-
-                case MBEDTLS_X509_EXT_SUBJECT_ALT_NAME:
-                    /* Parse subject alt name */
-                    if ((ret = mbedtls_x509_get_subject_alt_name(p, end_ext_data,
-                                                                 &csr->subject_alt_names)) != 0) {
-                        return ret;
-                    }
-                    break;
-
-                case MBEDTLS_X509_EXT_NS_CERT_TYPE:
-                    /* Parse netscape certificate type */
-                    if ((ret = mbedtls_x509_get_ns_cert_type(p, end_ext_data,
-                                                             &csr->ns_cert_type)) != 0) {
-                        return ret;
-                    }
-                    break;
-                default:
-                    break;
-            }
+            continue;
         }
-        *p = end_ext_data;
+
+        /* Forbid repeated extensions */
+        if ((csr->ext_types & ext_type) != 0) {
+            return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
+                                     MBEDTLS_ERR_ASN1_INVALID_DATA);
+        }
+
+        csr->ext_types |= ext_type;
+
+        switch (ext_type) {
+            case MBEDTLS_X509_EXT_KEY_USAGE:
+                /* Parse key usage */
+                if ((ret = mbedtls_x509_get_key_usage(p, end_ext_data,
+                                                      &csr->key_usage)) != 0) {
+                    return ret;
+                }
+                break;
+
+            case MBEDTLS_X509_EXT_SUBJECT_ALT_NAME:
+                /* Parse subject alt name */
+                if ((ret = mbedtls_x509_get_subject_alt_name(p, end_ext_data,
+                                                             &csr->subject_alt_names)) != 0) {
+                    return ret;
+                }
+                break;
+
+            case MBEDTLS_X509_EXT_NS_CERT_TYPE:
+                /* Parse netscape certificate type */
+                if ((ret = mbedtls_x509_get_ns_cert_type(p, end_ext_data,
+                                                         &csr->ns_cert_type)) != 0) {
+                    return ret;
+                }
+                break;
+            default:
+                /*
+                 * If this is a non-critical extension, which the oid layer
+                 * supports, but there isn't an x509 parser for it,
+                 * skip the extension.
+                 */
+                if (is_critical) {
+                    return MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE;
+                } else {
+                    *p = end_ext_octet;
+                }
+        }
     }
 
     if (*p != end) {
@@ -156,7 +196,9 @@
  * Parse CSR attributes in DER format
  */
 static int x509_csr_parse_attributes(mbedtls_x509_csr *csr,
-                                     const unsigned char *start, const unsigned char *end)
+                                     const unsigned char *start, const unsigned char *end,
+                                     mbedtls_x509_csr_ext_cb_t cb,
+                                     void *p_ctx)
 {
     int ret;
     size_t len;
@@ -195,7 +237,7 @@
                 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
             }
 
-            if ((ret = x509_csr_parse_extensions(csr, p, *p + len)) != 0) {
+            if ((ret = x509_csr_parse_extensions(csr, p, *p + len, cb, p_ctx)) != 0) {
                 return ret;
             }
 
@@ -219,8 +261,10 @@
 /*
  * Parse a CSR in DER format
  */
-int mbedtls_x509_csr_parse_der(mbedtls_x509_csr *csr,
-                               const unsigned char *buf, size_t buflen)
+static int mbedtls_x509_csr_parse_der_internal(mbedtls_x509_csr *csr,
+                                               const unsigned char *buf, size_t buflen,
+                                               mbedtls_x509_csr_ext_cb_t cb,
+                                               void *p_ctx)
 {
     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
     size_t len;
@@ -344,7 +388,7 @@
         return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_FORMAT, ret);
     }
 
-    if ((ret = x509_csr_parse_attributes(csr, p, p + len)) != 0) {
+    if ((ret = x509_csr_parse_attributes(csr, p, p + len, cb, p_ctx)) != 0) {
         mbedtls_x509_csr_free(csr);
         return ret;
     }
@@ -384,6 +428,26 @@
 }
 
 /*
+ * Parse a CSR in DER format
+ */
+int mbedtls_x509_csr_parse_der(mbedtls_x509_csr *csr,
+                               const unsigned char *buf, size_t buflen)
+{
+    return mbedtls_x509_csr_parse_der_internal(csr, buf, buflen, NULL, NULL);
+}
+
+/*
+ * Parse a CSR in DER format with callback for unknown extensions
+ */
+int mbedtls_x509_csr_parse_der_with_ext_cb(mbedtls_x509_csr *csr,
+                                           const unsigned char *buf, size_t buflen,
+                                           mbedtls_x509_csr_ext_cb_t cb,
+                                           void *p_ctx)
+{
+    return mbedtls_x509_csr_parse_der_internal(csr, buf, buflen, cb, p_ctx);
+}
+
+/*
  * Parse a CSR, allowing for PEM or raw DER encoding
  */
 int mbedtls_x509_csr_parse(mbedtls_x509_csr *csr, const unsigned char *buf, size_t buflen)
diff --git a/scripts/find-mem-leak.cocci b/scripts/find-mem-leak.cocci
deleted file mode 100644
index 8179e2b..0000000
--- a/scripts/find-mem-leak.cocci
+++ /dev/null
@@ -1,20 +0,0 @@
-@@
-expression x, y;
-statement S;
-@@
-  x = mbedtls_calloc(...);
-  y = mbedtls_calloc(...);
-  ...
-* if (x == NULL || y == NULL)
-    S
-
-@@
-expression x, y;
-statement S;
-@@
-  if (
-*   (x = mbedtls_calloc(...)) == NULL
-    ||
-*   (y = mbedtls_calloc(...)) == NULL
-  )
-    S
diff --git a/scripts/rm-calloc-cast.cocci b/scripts/rm-calloc-cast.cocci
deleted file mode 100644
index 89481c0..0000000
--- a/scripts/rm-calloc-cast.cocci
+++ /dev/null
@@ -1,7 +0,0 @@
-@rm_calloc_cast@
-expression x, n, m;
-type T;
-@@
-  x =
-- (T *)
-  mbedtls_calloc(n, m)
diff --git a/tests/opt-testcases/tls13-kex-modes.sh b/tests/opt-testcases/tls13-kex-modes.sh
index 6556cd4..4581bc5 100755
--- a/tests/opt-testcases/tls13-kex-modes.sh
+++ b/tests/opt-testcases/tls13-kex-modes.sh
@@ -550,7 +550,7 @@
             -s "found pre_shared_key extension" \
             -S "Found PSK_EPHEMERAL KEX MODE" \
             -s "Found PSK KEX MODE" \
-            -s "Pre shared key found" \
+            -S "Pre shared key found" \
             -S "No matched PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
@@ -733,7 +733,7 @@
             -s "found pre_shared_key extension" \
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -S "Found PSK KEX MODE" \
-            -s "Pre shared key found" \
+            -S "Pre shared key found" \
             -S "No matched PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
@@ -1413,7 +1413,7 @@
             -s "found pre_shared_key extension" \
             -s "Found PSK_EPHEMERAL KEX MODE" \
             -S "Found PSK KEX MODE" \
-            -s "Pre shared key found" \
+            -S "Pre shared key found" \
             -S "No matched PSK or ticket" \
             -S "key exchange mode: psk$"  \
             -S "key exchange mode: psk_ephemeral"  \
diff --git a/tests/opt-testcases/tls13-misc.sh b/tests/opt-testcases/tls13-misc.sh
index 3182b48..3816a2b 100755
--- a/tests/opt-testcases/tls13-misc.sh
+++ b/tests/opt-testcases/tls13-misc.sh
@@ -411,7 +411,8 @@
          0 \
          -c "Pre-configured PSK number = 1" \
          -S "No suitable key exchange mode" \
-         -s "found matched identity"
+         -s "found matched identity" \
+         -s "key exchange mode: psk_ephemeral"
 
 requires_all_configs_enabled MBEDTLS_SSL_SESSION_TICKETS \
                              MBEDTLS_SSL_SRV_C MBEDTLS_SSL_CLI_C MBEDTLS_DEBUG_C \
@@ -423,7 +424,8 @@
          0 \
          -c "Pre-configured PSK number = 1" \
          -S "No suitable key exchange mode" \
-         -s "found matched identity"
+         -s "found matched identity" \
+         -s "key exchange mode: psk_ephemeral"
 
 requires_all_configs_enabled MBEDTLS_SSL_SESSION_TICKETS \
                              MBEDTLS_SSL_SRV_C MBEDTLS_SSL_CLI_C MBEDTLS_DEBUG_C \
@@ -466,7 +468,8 @@
          0 \
          -c "Pre-configured PSK number = 1" \
          -S "No suitable key exchange mode" \
-         -s "found matched identity"
+         -s "found matched identity" \
+         -s "key exchange mode: psk_ephemeral"
 
 requires_all_configs_enabled MBEDTLS_SSL_SESSION_TICKETS \
                              MBEDTLS_SSL_SRV_C MBEDTLS_SSL_CLI_C MBEDTLS_DEBUG_C \
@@ -479,7 +482,11 @@
          0 \
          -c "Pre-configured PSK number = 1" \
          -S "No suitable key exchange mode" \
-         -s "found matched identity"
+         -s "found matched identity" \
+         -s "key exchange mode: psk_ephemeral"
+
+EARLY_DATA_INPUT_LEN_BLOCKS=$(( ( $( cat $EARLY_DATA_INPUT | wc -c ) + 31 ) / 32 ))
+EARLY_DATA_INPUT_LEN=$(( $EARLY_DATA_INPUT_LEN_BLOCKS * 32 ))
 
 requires_gnutls_next
 requires_all_configs_enabled MBEDTLS_SSL_EARLY_DATA MBEDTLS_SSL_SESSION_TICKETS     \
@@ -496,3 +503,20 @@
          -s "EncryptedExtensions: early_data(42) extension does not exist."    \
          -s "NewSessionTicket: early_data(42) extension does not exist."        \
          -s "Last error was: -29056 - SSL - Verification of the message MAC failed"
+
+requires_gnutls_next
+requires_all_configs_enabled MBEDTLS_SSL_EARLY_DATA MBEDTLS_SSL_SESSION_TICKETS \
+                             MBEDTLS_SSL_SRV_C MBEDTLS_DEBUG_C MBEDTLS_HAVE_TIME \
+                             MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL_ENABLED \
+                             MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
+requires_any_configs_enabled MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_ENABLED \
+                             MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL_ENABLED
+run_test "TLS 1.3 G->m: EarlyData: feature is enabled, fail." \
+         "$P_SRV force_version=tls13 debug_level=4 max_early_data_size=$EARLY_DATA_INPUT_LEN" \
+         "$G_NEXT_CLI localhost --priority=NORMAL:-VERS-ALL:+VERS-TLS1.3:+GROUP-ALL:+KX-ALL \
+                      -d 10 -r --earlydata $EARLY_DATA_INPUT " \
+         1 \
+         -s "ClientHello: early_data(42) extension exists."                 \
+         -s "EncryptedExtensions: early_data(42) extension exists."         \
+         -s "NewSessionTicket: early_data(42) extension does not exist."    \
+         -s "Last error was: -29056 - SSL - Verification of the message MAC failed"
diff --git a/tests/ssl-opt.sh b/tests/ssl-opt.sh
index 8e8e2a1..9c317d1 100755
--- a/tests/ssl-opt.sh
+++ b/tests/ssl-opt.sh
@@ -113,6 +113,7 @@
 SHOW_TEST_NUMBER=0
 LIST_TESTS=0
 RUN_TEST_NUMBER=''
+RUN_TEST_SUITE=''
 
 PRESERVE_LOGS=0
 
@@ -137,6 +138,8 @@
     printf "     --port     \tTCP/UDP port (default: randomish 1xxxx)\n"
     printf "     --proxy-port\tTCP/UDP proxy port (default: randomish 2xxxx)\n"
     printf "     --seed     \tInteger seed value to use for this test run\n"
+    printf "     --test-suite\tOnly matching test suites are executed\n"
+    printf "                 \t(comma-separated, e.g. 'ssl-opt,tls13-compat')\n\n"
 }
 
 get_options() {
@@ -175,6 +178,9 @@
             --seed)
                 shift; SEED="$1"
                 ;;
+            --test-suite)
+                shift; RUN_TEST_SUITE="$1"
+                ;;
             -h|--help)
                 print_usage
                 exit 0
@@ -883,7 +889,7 @@
     if [ -n "$MBEDTLS_TEST_OUTCOME_FILE" ]; then
         printf '%s;%s;%s;%s;%s;%s\n' \
                "$MBEDTLS_TEST_PLATFORM" "$MBEDTLS_TEST_CONFIGURATION" \
-               "ssl-opt" "$NAME" \
+               "${TEST_SUITE_NAME:-ssl-opt}" "$NAME" \
                "$1" "${2-}" \
                >>"$MBEDTLS_TEST_OUTCOME_FILE"
     fi
@@ -1590,6 +1596,13 @@
         return
     fi
 
+    # Use ssl-opt as default test suite name. Also see record_outcome function
+    if is_excluded_test_suite "${TEST_SUITE_NAME:-ssl-opt}"; then
+        # Do not skip next test and skip current test.
+        SKIP_NEXT="NO"
+        return
+    fi
+
     print_name "$NAME"
 
     # Do we only run numbered tests?
@@ -1837,6 +1850,21 @@
     }
 fi
 
+# Filter tests according to TEST_SUITE_NAME
+is_excluded_test_suite () {
+    if [ -n "$RUN_TEST_SUITE" ]
+    then
+        case ",$RUN_TEST_SUITE," in
+            *",$1,"*) false;;
+            *) true;;
+        esac
+    else
+        false
+    fi
+
+}
+
+
 if [ "$LIST_TESTS" -eq 0 ];then
 
     # sanity checks, avoid an avalanche of errors
diff --git a/tests/suites/test_suite_constant_time_hmac.function b/tests/suites/test_suite_constant_time_hmac.function
index 435e4b9..9d9aa3c 100644
--- a/tests/suites/test_suite_constant_time_hmac.function
+++ b/tests/suites/test_suite_constant_time_hmac.function
@@ -4,6 +4,7 @@
 #include <mbedtls/md.h>
 #include <constant_time_internal.h>
 #include "md_psa.h"
+#include <ssl_misc.h>
 
 #include <test/constant_flow.h>
 /* END_HEADER */
diff --git a/tests/suites/test_suite_version.data b/tests/suites/test_suite_version.data
index 11c41b0..faa3166 100644
--- a/tests/suites/test_suite_version.data
+++ b/tests/suites/test_suite_version.data
@@ -1,8 +1,8 @@
 Check compile time library version
-check_compiletime_version:"3.5.0"
+check_compiletime_version:"3.5.1"
 
 Check runtime library version
-check_runtime_version:"3.5.0"
+check_runtime_version:"3.5.1"
 
 Check for MBEDTLS_VERSION_C
 check_feature:"MBEDTLS_VERSION_C":0
diff --git a/tests/suites/test_suite_x509parse.data b/tests/suites/test_suite_x509parse.data
index 4b75f17..261c220 100644
--- a/tests/suites/test_suite_x509parse.data
+++ b/tests/suites/test_suite_x509parse.data
@@ -2940,6 +2940,26 @@
 depends_on:MBEDTLS_PK_CAN_ECDSA_SOME:MBEDTLS_ECP_HAVE_SECP256R1:MBEDTLS_MD_CAN_SHA1:!MBEDTLS_X509_REMOVE_INFO
 mbedtls_x509_csr_parse:"308201183081bf0201003034310b3009060355040613024e4c3111300f060355040a1308506f6c617253534c31123010060355040313096c6f63616c686f73743059301306072a8648ce3d020106082a8648ce3d0301070342000437cc56d976091e5a723ec7592dff206eee7cf9069174d0ad14b5f768225962924ee500d82311ffea2fd2345d5d16bd8a88c26b770d55cd8a2a0efa01c8b4edffa029302706092a864886f70d01090e311a301830090603551d1304023000300b0603551d0f0404030205e0300906072a8648ce3d04010349003046022100b49fd8c8f77abfa871908dfbe684a08a793d0f490a43d86fcf2086e4f24bb0c2022100f829d5ccd3742369299e6294394717c4b723a0f68b44e831b6e6c3bcabf97243":"CSR version   \: 1\nsubject name  \: C=NL, O=PolarSSL, CN=localhost\nsigned using  \: ECDSA with SHA1\nEC key size   \: 256 bits\n\nkey usage         \: Digital Signature, Non Repudiation, Key Encipherment\n":0
 
+X509 CSR ASN.1 (Unsupported critical extension, critical=true)
+depends_on:MBEDTLS_PK_CAN_ECDSA_SOME:MBEDTLS_ECP_HAVE_SECP256R1:MBEDTLS_MD_CAN_SHA256:!MBEDTLS_X509_REMOVE_INFO
+mbedtls_x509_csr_parse:"308201233081cb02010030413119301706035504030c1053656c66207369676e65642074657374310b300906035504061302444531173015060355040a0c0e41757468437274444220546573743059301306072a8648ce3d020106082a8648ce3d03010703420004c11ebb9951848a436ca2c8a73382f24bbb6c28a92e401d4889b0c361f377b92a8b0497ff2f5a5f6057ae85f704ab1850bef075914f68ed3aeb15a1ff1ebc0dc6a028302606092a864886f70d01090e311930173015060b2b0601040183890c8622020101ff0403010101300a06082a8648ce3d040302034700304402200c4108fd098525993d3fd5b113f0a1ead8750852baf55a2f8e670a22cabc0ba1022034db93a0fcb993912adcf2ea8cb4b66389af30e264d43c0daea03255e45d2ccc":"":MBEDTLS_ERR_X509_INVALID_EXTENSIONS+MBEDTLS_ERR_ASN1_UNEXPECTED_TAG
+
+X509 CSR ASN.1 (Unsupported non-critical extension, critical=false)
+depends_on:MBEDTLS_PK_CAN_ECDSA_SOME:MBEDTLS_ECP_HAVE_SECP256R1:MBEDTLS_MD_CAN_SHA256:!MBEDTLS_X509_REMOVE_INFO
+mbedtls_x509_csr_parse:"308201243081cb02010030413119301706035504030c1053656c66207369676e65642074657374310b300906035504061302444531173015060355040a0c0e41757468437274444220546573743059301306072a8648ce3d020106082a8648ce3d03010703420004b5e718a7df6b21912733e77c42f266b8283e6cae7adf8afd56b990c1c6232ea0a2a46097c218353bc948444aea3d00423e84802e28c48099641fe9977cdfb505a028302606092a864886f70d01090e311930173015060b2b0601040183890c8622020101000403010101300a06082a8648ce3d0403020348003045022100f0ba9a0846ad0a7cefd0a61d5fc92194dc06037a44158de2d0c569912c058d430220421f27a9f249c1687e2fa34db3f543c8512fd925dfe5ae00867f13963ffd4f8d":"CSR version   \: 1\nsubject name  \: CN=Self signed test, C=DE, O=AuthCrtDB Test\nsigned using  \: ECDSA with SHA256\nEC key size   \: 256 bits\n":0
+
+X509 CSR ASN.1 (Unsupported non-critical extension, critical undefined)
+depends_on:MBEDTLS_PK_CAN_ECDSA_SOME:MBEDTLS_ECP_HAVE_SECP256R1:MBEDTLS_MD_CAN_SHA256:!MBEDTLS_X509_REMOVE_INFO
+mbedtls_x509_csr_parse:"308201223081c802010030413119301706035504030c1053656c66207369676e65642074657374310b300906035504061302444531173015060355040a0c0e41757468437274444220546573743059301306072a8648ce3d020106082a8648ce3d030107034200045f94b28d133418833bf10c442d91306459d3925e7cea06ebb9220932e7de116fb671c5d2d6c0a3784a12897217aef8432e7228fcea0ab016bdb67b67ced4c612a025302306092a864886f70d01090e311630143012060b2b0601040183890c8622020403010101300a06082a8648ce3d04030203490030460221009b1e8b25775c18525e96753e1ed55875f8d62f026c5b7f70eb5037ad27dc92de022100ba1dfe14de6af6a603f763563fd046b1cd3714b54d6daf5d8a72076497f11014":"CSR version   \: 1\nsubject name  \: CN=Self signed test, C=DE, O=AuthCrtDB Test\nsigned using  \: ECDSA with SHA256\nEC key size   \: 256 bits\n":0
+
+X509 CSR ASN.1 (Unsupported critical extension accepted by callback, critical=true)
+depends_on:MBEDTLS_PK_CAN_ECDSA_SOME:MBEDTLS_ECP_HAVE_SECP256R1:MBEDTLS_MD_CAN_SHA256:!MBEDTLS_X509_REMOVE_INFO
+mbedtls_x509_csr_parse_with_ext_cb:"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":"CSR version   \: 1\nsubject name  \: CN=Self signed test, C=DE, O=AuthCrtDB Test\nsigned using  \: ECDSA with SHA256\nEC key size   \: 256 bits\n":0:1
+
+X509 CSR ASN.1 (Unsupported critical extension rejected by callback, critical=true)
+depends_on:MBEDTLS_PK_CAN_ECDSA_SOME:MBEDTLS_ECP_HAVE_SECP256R1:MBEDTLS_MD_CAN_SHA256:!MBEDTLS_X509_REMOVE_INFO
+mbedtls_x509_csr_parse_with_ext_cb:"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":"":MBEDTLS_ERR_X509_INVALID_EXTENSIONS+MBEDTLS_ERR_ASN1_UNEXPECTED_TAG:0
+
 X509 CSR ASN.1 (bad first tag)
 mbedtls_x509_csr_parse:"3100":"":MBEDTLS_ERR_X509_INVALID_FORMAT
 
diff --git a/tests/suites/test_suite_x509parse.function b/tests/suites/test_suite_x509parse.function
index 894e0bb..c2a2f55 100644
--- a/tests/suites/test_suite_x509parse.function
+++ b/tests/suites/test_suite_x509parse.function
@@ -250,7 +250,8 @@
 
                 ret = mbedtls_oid_get_numeric_string(p,
                                                      n,
-                                                     &san->san.other_name.value.hardware_module_name.oid);
+                                                     &san->san.other_name.value.hardware_module_name
+                                                     .oid);
                 MBEDTLS_X509_SAFE_SNPRINTF;
 
                 ret = mbedtls_snprintf(p, n, ", hardware serial number : ");
@@ -413,6 +414,35 @@
     }
 }
 #endif /* MBEDTLS_X509_CRT_PARSE_C */
+
+#if defined(MBEDTLS_X509_CSR_PARSE_C)
+int parse_csr_ext_accept_cb(void *p_ctx, mbedtls_x509_csr const *csr, mbedtls_x509_buf const *oid,
+                            int critical, const unsigned char *cp, const unsigned char *end)
+{
+    (void) p_ctx;
+    (void) csr;
+    (void) oid;
+    (void) critical;
+    (void) cp;
+    (void) end;
+
+    return 0;
+}
+
+int parse_csr_ext_reject_cb(void *p_ctx, mbedtls_x509_csr const *csr, mbedtls_x509_buf const *oid,
+                            int critical, const unsigned char *cp, const unsigned char *end)
+{
+    (void) p_ctx;
+    (void) csr;
+    (void) oid;
+    (void) critical;
+    (void) cp;
+    (void) end;
+
+    return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
+                             MBEDTLS_ERR_ASN1_UNEXPECTED_TAG);
+}
+#endif /* MBEDTLS_X509_CSR_PARSE_C */
 /* END_HEADER */
 
 /* BEGIN_CASE depends_on:MBEDTLS_X509_CRT_PARSE_C */
@@ -1247,6 +1277,36 @@
 }
 /* END_CASE */
 
+/* BEGIN_CASE depends_on:MBEDTLS_X509_CSR_PARSE_C:!MBEDTLS_X509_REMOVE_INFO */
+void mbedtls_x509_csr_parse_with_ext_cb(data_t *csr_der, char *ref_out, int ref_ret, int accept)
+{
+    mbedtls_x509_csr csr;
+    char my_out[1000];
+    int my_ret;
+
+    mbedtls_x509_csr_init(&csr);
+    USE_PSA_INIT();
+
+    memset(my_out, 0, sizeof(my_out));
+
+    my_ret = mbedtls_x509_csr_parse_der_with_ext_cb(&csr, csr_der->x, csr_der->len,
+                                                    accept ? parse_csr_ext_accept_cb :
+                                                    parse_csr_ext_reject_cb,
+                                                    NULL);
+    TEST_EQUAL(my_ret, ref_ret);
+
+    if (ref_ret == 0) {
+        size_t my_out_len = mbedtls_x509_csr_info(my_out, sizeof(my_out), "", &csr);
+        TEST_EQUAL(my_out_len, strlen(ref_out));
+        TEST_EQUAL(strcmp(my_out, ref_out), 0);
+    }
+
+exit:
+    mbedtls_x509_csr_free(&csr);
+    USE_PSA_DONE();
+}
+/* END_CASE */
+
 /* BEGIN_CASE depends_on:MBEDTLS_FS_IO:MBEDTLS_X509_CSR_PARSE_C:!MBEDTLS_X509_REMOVE_INFO */
 void mbedtls_x509_csr_parse_file(char *csr_file, char *ref_out, int ref_ret)
 {