Merge pull request #8692 from ronald-cron-arm/read-early-data

TLS 1.3: SRV: Implement mbedtls_ssl_read_early_data()
diff --git a/include/mbedtls/ssl.h b/include/mbedtls/ssl.h
index 3629526..b063360 100644
--- a/include/mbedtls/ssl.h
+++ b/include/mbedtls/ssl.h
@@ -90,8 +90,18 @@
 #define MBEDTLS_ERR_SSL_RECEIVED_NEW_SESSION_TICKET       -0x7B00
 /** Not possible to read early data */
 #define MBEDTLS_ERR_SSL_CANNOT_READ_EARLY_DATA            -0x7B80
+/**
+ * Early data has been received as part of an on-going handshake.
+ * This error code can be returned only on server side if and only if early
+ * data has been enabled by means of the mbedtls_ssl_conf_early_data() API.
+ * This error code can then be returned by mbedtls_ssl_handshake(),
+ * mbedtls_ssl_handshake_step(), mbedtls_ssl_read() or mbedtls_ssl_write() if
+ * early data has been received as part of the handshake sequence they
+ * triggered. To read the early data, call mbedtls_ssl_read_early_data().
+ */
+#define MBEDTLS_ERR_SSL_RECEIVED_EARLY_DATA               -0x7C00
 /** Not possible to write early data */
-#define MBEDTLS_ERR_SSL_CANNOT_WRITE_EARLY_DATA           -0x7C00
+#define MBEDTLS_ERR_SSL_CANNOT_WRITE_EARLY_DATA           -0x7C80
 /* Error space gap */
 /* Error space gap */
 /* Error space gap */
@@ -1644,6 +1654,18 @@
      */
     mbedtls_ssl_protocol_version MBEDTLS_PRIVATE(tls_version);
 
+#if defined(MBEDTLS_SSL_EARLY_DATA) && defined(MBEDTLS_SSL_CLI_C)
+    /**
+     *  Status of the negotiation of the use of early data.
+     *  See the documentation of mbedtls_ssl_get_early_data_status() for more
+     *  information.
+     *
+     *  Reset to #MBEDTLS_SSL_EARLY_DATA_STATUS_NOT_SENT when the context is
+     *  reset.
+     */
+    int MBEDTLS_PRIVATE(early_data_status);
+#endif
+
     unsigned MBEDTLS_PRIVATE(badmac_seen);       /*!< records with a bad MAC received    */
 
 #if defined(MBEDTLS_X509_CRT_PARSE_C)
@@ -1841,10 +1863,6 @@
                                              *   and #MBEDTLS_SSL_CID_DISABLED. */
 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
 
-#if defined(MBEDTLS_SSL_EARLY_DATA)
-    int MBEDTLS_PRIVATE(early_data_status);
-#endif /* MBEDTLS_SSL_EARLY_DATA && MBEDTLS_SSL_CLI_C */
-
     /** Callback to export key block and master secret                      */
     mbedtls_ssl_export_keys_t *MBEDTLS_PRIVATE(f_export_keys);
     void *MBEDTLS_PRIVATE(p_export_keys);            /*!< context for key export callback    */
@@ -1993,7 +2011,7 @@
  */
 void mbedtls_ssl_conf_authmode(mbedtls_ssl_config *conf, int authmode);
 
-#if defined(MBEDTLS_SSL_PROTO_TLS1_3) && defined(MBEDTLS_SSL_EARLY_DATA)
+#if defined(MBEDTLS_SSL_EARLY_DATA)
 /**
  * \brief    Set the early data mode
  *           Default: disabled on server and client
@@ -2001,14 +2019,24 @@
  * \param conf   The SSL configuration to use.
  * \param early_data_enabled can be:
  *
- *  MBEDTLS_SSL_EARLY_DATA_DISABLED:  early data functionality is disabled
- *                                    This is the default on client and server.
+ *  MBEDTLS_SSL_EARLY_DATA_DISABLED:
+ *  Early data functionality is disabled. This is the default on client and
+ *  server.
  *
- *  MBEDTLS_SSL_EARLY_DATA_ENABLED:  early data functionality is enabled and
- *                        may be negotiated in the handshake. Application using
- *                        early data functionality needs to be aware of the
- *                        lack of replay protection of the early data application
- *                        payloads.
+ *  MBEDTLS_SSL_EARLY_DATA_ENABLED:
+ *  Early data functionality is enabled and may be negotiated in the handshake.
+ *  Application using early data functionality needs to be aware that the
+ *  security properties for early data (also refered to as 0-RTT data) are
+ *  weaker than those for other kinds of TLS data. See the documentation of
+ *  mbedtls_ssl_write_early_data() and mbedtls_ssl_read_early_data() for more
+ *  information.
+ *  When early data functionality is enabled on server and only in that case,
+ *  the call to one of the APIs that trigger or resume an handshake sequence,
+ *  namely mbedtls_ssl_handshake(), mbedtls_ssl_handshake_step(),
+ *  mbedtls_ssl_read() or mbedtls_ssl_write() may return with the error code
+ *  MBEDTLS_ERR_SSL_RECEIVED_EARLY_DATA indicating that some early data have
+ *  been received. To read the early data, call mbedtls_ssl_read_early_data()
+ *  before calling the original function again.
  *
  * \warning This interface is experimental and may change without notice.
  *
@@ -2048,7 +2076,7 @@
     mbedtls_ssl_config *conf, uint32_t max_early_data_size);
 #endif /* MBEDTLS_SSL_SRV_C */
 
-#endif /* MBEDTLS_SSL_PROTO_TLS1_3 && MBEDTLS_SSL_EARLY_DATA */
+#endif /* MBEDTLS_SSL_EARLY_DATA */
 
 #if defined(MBEDTLS_X509_CRT_PARSE_C)
 /**
@@ -4733,6 +4761,13 @@
  * \return         #MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED if DTLS is in use
  *                 and the client did not demonstrate reachability yet - in
  *                 this case you must stop using the context (see below).
+ * \return         #MBEDTLS_ERR_SSL_RECEIVED_EARLY_DATA if early data, as
+ *                 defined in RFC 8446 (TLS 1.3 specification), has been
+ *                 received as part of the handshake. This is server specific
+ *                 and may occur only if the early data feature has been
+ *                 enabled on server (see mbedtls_ssl_conf_early_data()
+ *                 documentation). You must call mbedtls_ssl_read_early_data()
+ *                 to read the early data before resuming the handshake.
  * \return         Another SSL error code - in this case you must stop using
  *                 the context (see below).
  *
@@ -4741,7 +4776,8 @@
  *                 #MBEDTLS_ERR_SSL_WANT_READ,
  *                 #MBEDTLS_ERR_SSL_WANT_WRITE,
  *                 #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS or
- *                 #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS,
+ *                 #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS or
+ *                 #MBEDTLS_ERR_SSL_RECEIVED_EARLY_DATA,
  *                 you must stop using the SSL context for reading or writing,
  *                 and either free it or call \c mbedtls_ssl_session_reset()
  *                 on it before re-using it for a new connection; the current
@@ -4810,8 +4846,9 @@
  *
  * \warning        If this function returns something other than \c 0,
  *                 #MBEDTLS_ERR_SSL_WANT_READ, #MBEDTLS_ERR_SSL_WANT_WRITE,
- *                 #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS or
- *                 #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS, you must stop using
+ *                 #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS,
+ *                 #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS or
+ *                 #MBEDTLS_ERR_SSL_RECEIVED_EARLY_DATA, you must stop using
  *                 the SSL context for reading or writing, and either free it
  *                 or call \c mbedtls_ssl_session_reset() on it before
  *                 re-using it for a new connection; the current connection
@@ -4879,6 +4916,13 @@
  * \return         #MBEDTLS_ERR_SSL_CLIENT_RECONNECT if we're at the server
  *                 side of a DTLS connection and the client is initiating a
  *                 new connection using the same source port. See below.
+ * \return         #MBEDTLS_ERR_SSL_RECEIVED_EARLY_DATA if early data, as
+ *                 defined in RFC 8446 (TLS 1.3 specification), has been
+ *                 received as part of the handshake. This is server specific
+ *                 and may occur only if the early data feature has been
+ *                 enabled on server (see mbedtls_ssl_conf_early_data()
+ *                 documentation). You must call mbedtls_ssl_read_early_data()
+ *                 to read the early data before resuming the handshake.
  * \return         Another SSL error code - in this case you must stop using
  *                 the context (see below).
  *
@@ -4887,8 +4931,9 @@
  *                 #MBEDTLS_ERR_SSL_WANT_READ,
  *                 #MBEDTLS_ERR_SSL_WANT_WRITE,
  *                 #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS,
- *                 #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS or
- *                 #MBEDTLS_ERR_SSL_CLIENT_RECONNECT,
+ *                 #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS,
+ *                 #MBEDTLS_ERR_SSL_CLIENT_RECONNECT or
+ *                 #MBEDTLS_ERR_SSL_RECEIVED_EARLY_DATA,
  *                 you must stop using the SSL context for reading or writing,
  *                 and either free it or call \c mbedtls_ssl_session_reset()
  *                 on it before re-using it for a new connection; the current
@@ -4953,6 +4998,13 @@
  *                 operation is in progress (see mbedtls_ecp_set_max_ops()) -
  *                 in this case you must call this function again to complete
  *                 the handshake when you're done attending other tasks.
+ * \return         #MBEDTLS_ERR_SSL_RECEIVED_EARLY_DATA if early data, as
+ *                 defined in RFC 8446 (TLS 1.3 specification), has been
+ *                 received as part of the handshake. This is server specific
+ *                 and may occur only if the early data feature has been
+ *                 enabled on server (see mbedtls_ssl_conf_early_data()
+ *                 documentation). You must call mbedtls_ssl_read_early_data()
+ *                 to read the early data before resuming the handshake.
  * \return         Another SSL error code - in this case you must stop using
  *                 the context (see below).
  *
@@ -4960,8 +5012,9 @@
  *                 a non-negative value,
  *                 #MBEDTLS_ERR_SSL_WANT_READ,
  *                 #MBEDTLS_ERR_SSL_WANT_WRITE,
- *                 #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS or
- *                 #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS,
+ *                 #MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS,
+ *                 #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS or
+ *                 #MBEDTLS_ERR_SSL_RECEIVED_EARLY_DATA,
  *                 you must stop using the SSL context for reading or writing,
  *                 and either free it or call \c mbedtls_ssl_session_reset()
  *                 on it before re-using it for a new connection; the current
@@ -5029,48 +5082,46 @@
 
 #if defined(MBEDTLS_SSL_SRV_C)
 /**
- * \brief          Read at most 'len' application data bytes while performing
- *                 the handshake (early data).
+ * \brief          Read at most 'len' bytes of early data
  *
- * \note           This function behaves mainly as mbedtls_ssl_read(). The
- *                 specification of mbedtls_ssl_read() relevant to TLS 1.3
- *                 (thus not the parts specific to (D)TLS 1.2) applies to this
- *                 function and the present documentation is restricted to the
- *                 differences with mbedtls_ssl_read().
+ * \note           This API is server specific.
  *
- * \param ssl      SSL context
+ * \warning        Early data is defined in the TLS 1.3 specification, RFC 8446.
+ *                 IMPORTANT NOTE from section 2.3 of the specification:
+ *
+ *                 The security properties for 0-RTT data are weaker than
+ *                 those for other kinds of TLS data. Specifically:
+ *                 - This data is not forward secret, as it is encrypted
+ *                   solely under keys derived using the offered PSK.
+ *                 - There are no guarantees of non-replay between connections.
+ *                   Protection against replay for ordinary TLS 1.3 1-RTT data
+ *                   is provided via the server's Random value, but 0-RTT data
+ *                   does not depend on the ServerHello and therefore has
+ *                   weaker guarantees. This is especially relevant if the
+ *                   data is authenticated either with TLS client
+ *                   authentication or inside the application protocol. The
+ *                   same warnings apply to any use of the
+ *                   early_exporter_master_secret.
+ *
+ * \note           This function is used in conjunction with
+ *                 mbedtls_ssl_handshake(), mbedtls_ssl_handshake_step(),
+ *                 mbedtls_ssl_read() and mbedtls_ssl_write() to read early
+ *                 data when these functions return
+ *                 #MBEDTLS_ERR_SSL_RECEIVED_EARLY_DATA.
+ *
+ * \param ssl      SSL context, it must have been initialized and set up.
  * \param buf      buffer that will hold the data
  * \param len      maximum number of bytes to read
  *
- * \return         One additional specific return value:
- *                 #MBEDTLS_ERR_SSL_CANNOT_READ_EARLY_DATA.
- *
- *                 #MBEDTLS_ERR_SSL_CANNOT_READ_EARLY_DATA is returned when it
- *                 is not possible to read early data for the SSL context
- *                 \p ssl.
- *
- *                 It may have been possible and it is not possible
- *                 anymore because the server received the End of Early Data
- *                 message or the maximum number of allowed early data for the
- *                 PSK in use has been reached.
- *
- *                 It may never have been possible and will never be possible
- *                 for the SSL context \p ssl because the use of early data
- *                 is disabled for that context or more generally the context
- *                 is not suitably configured to enable early data or the
- *                 client does not use early data or the first call to the
- *                 function was done while the handshake was already too
- *                 advanced to gather and accept early data.
- *
- *                 It is not possible to read early data for the SSL context
- *                 \p ssl but this does not preclude for using it with
- *                 mbedtls_ssl_write(), mbedtls_ssl_read() or
- *                 mbedtls_ssl_handshake().
- *
- * \note           When a server wants to retrieve early data, it is expected
- *                 that this function starts the handshake for the SSL context
- *                 \p ssl. But this is not mandatory.
- *
+ * \return         The (positive) number of bytes read if successful.
+ * \return         #MBEDTLS_ERR_SSL_BAD_INPUT_DATA if input data is invalid.
+ * \return         #MBEDTLS_ERR_SSL_CANNOT_READ_EARLY_DATA if it is not
+ *                 possible to read early data for the SSL context \p ssl. Note
+ *                 that this function is intended to be called for an SSL
+ *                 context \p ssl only after a call to mbedtls_ssl_handshake(),
+ *                 mbedtls_ssl_handshake_step(), mbedtls_ssl_read() or
+ *                 mbedtls_ssl_write() for \p ssl that has returned
+ *                 #MBEDTLS_ERR_SSL_RECEIVED_EARLY_DATA.
  */
 int mbedtls_ssl_read_early_data(mbedtls_ssl_context *ssl,
                                 unsigned char *buf, size_t len);
diff --git a/library/ssl_misc.h b/library/ssl_misc.h
index 96afe76..c9632f9 100644
--- a/library/ssl_misc.h
+++ b/library/ssl_misc.h
@@ -650,6 +650,10 @@
     /* Flag indicating if a CertificateRequest message has been sent
      * to the client or not. */
     uint8_t certificate_request_sent;
+#if defined(MBEDTLS_SSL_EARLY_DATA)
+    /* Flag indicating if the server has accepted early data or not. */
+    uint8_t early_data_accepted;
+#endif
 #endif /* MBEDTLS_SSL_SRV_C */
 
 #if defined(MBEDTLS_SSL_SESSION_TICKETS)
@@ -2130,12 +2134,6 @@
                                            unsigned char *buf,
                                            const unsigned char *end,
                                            size_t *out_len);
-
-#if defined(MBEDTLS_SSL_SRV_C)
-#define MBEDTLS_SSL_EARLY_DATA_STATUS_NOT_RECEIVED \
-    MBEDTLS_SSL_EARLY_DATA_STATUS_NOT_SENT
-#endif /* MBEDTLS_SSL_SRV_C */
-
 #endif /* MBEDTLS_SSL_EARLY_DATA */
 
 #endif /* MBEDTLS_SSL_PROTO_TLS1_3 */
diff --git a/library/ssl_msg.c b/library/ssl_msg.c
index 6579c96..20501c9 100644
--- a/library/ssl_msg.c
+++ b/library/ssl_msg.c
@@ -5648,12 +5648,53 @@
 }
 
 /*
+ * brief          Read at most 'len' application data bytes from the input
+ *                buffer.
+ *
+ * param ssl      SSL context:
+ *                - First byte of application data not read yet in the input
+ *                  buffer located at address `in_offt`.
+ *                - The number of bytes of data not read yet is `in_msglen`.
+ * param buf      buffer that will hold the data
+ * param len      maximum number of bytes to read
+ *
+ * note           The function updates the fields `in_offt` and `in_msglen`
+ *                according to the number of bytes read.
+ *
+ * return         The number of bytes read.
+ */
+static int ssl_read_application_data(
+    mbedtls_ssl_context *ssl, unsigned char *buf, size_t len)
+{
+    size_t n = (len < ssl->in_msglen) ? len : ssl->in_msglen;
+
+    if (len != 0) {
+        memcpy(buf, ssl->in_offt, n);
+        ssl->in_msglen -= n;
+    }
+
+    /* Zeroising the plaintext buffer to erase unused application data
+       from the memory. */
+    mbedtls_platform_zeroize(ssl->in_offt, n);
+
+    if (ssl->in_msglen == 0) {
+        /* all bytes consumed */
+        ssl->in_offt = NULL;
+        ssl->keep_current_message = 0;
+    } else {
+        /* more data available */
+        ssl->in_offt += n;
+    }
+
+    return (int) n;
+}
+
+/*
  * Receive application data decrypted from the SSL layer
  */
 int mbedtls_ssl_read(mbedtls_ssl_context *ssl, unsigned char *buf, size_t len)
 {
     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
-    size_t n;
 
     if (ssl == NULL || ssl->conf == NULL) {
         return MBEDTLS_ERR_SSL_BAD_INPUT_DATA;
@@ -5817,32 +5858,34 @@
 #endif /* MBEDTLS_SSL_PROTO_DTLS */
     }
 
-    n = (len < ssl->in_msglen)
-        ? len : ssl->in_msglen;
-
-    if (len != 0) {
-        memcpy(buf, ssl->in_offt, n);
-        ssl->in_msglen -= n;
-    }
-
-    /* Zeroising the plaintext buffer to erase unused application data
-       from the memory. */
-    mbedtls_platform_zeroize(ssl->in_offt, n);
-
-    if (ssl->in_msglen == 0) {
-        /* all bytes consumed */
-        ssl->in_offt = NULL;
-        ssl->keep_current_message = 0;
-    } else {
-        /* more data available */
-        ssl->in_offt += n;
-    }
+    ret = ssl_read_application_data(ssl, buf, len);
 
     MBEDTLS_SSL_DEBUG_MSG(2, ("<= read"));
 
-    return (int) n;
+    return ret;
 }
 
+#if defined(MBEDTLS_SSL_SRV_C) && defined(MBEDTLS_SSL_EARLY_DATA)
+int mbedtls_ssl_read_early_data(mbedtls_ssl_context *ssl,
+                                unsigned char *buf, size_t len)
+{
+    if (ssl == NULL || (ssl->conf == NULL)) {
+        return MBEDTLS_ERR_SSL_BAD_INPUT_DATA;
+    }
+
+    /*
+     * The server may receive early data only while waiting for the End of
+     * Early Data handshake message.
+     */
+    if ((ssl->state != MBEDTLS_SSL_END_OF_EARLY_DATA) ||
+        (ssl->in_offt == NULL)) {
+        return MBEDTLS_ERR_SSL_CANNOT_READ_EARLY_DATA;
+    }
+
+    return ssl_read_application_data(ssl, buf, len);
+}
+#endif /* MBEDTLS_SSL_SRV_C && MBEDTLS_SSL_EARLY_DATA */
+
 /*
  * Send application data to be encrypted by the SSL layer, taking care of max
  * fragment length and buffer size.
diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index 0bc18f1..c952add 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -1098,6 +1098,10 @@
         return MBEDTLS_ERR_SSL_ALLOC_FAILED;
     }
 
+#if defined(MBEDTLS_SSL_EARLY_DATA) && defined(MBEDTLS_SSL_CLI_C)
+    ssl->early_data_status = MBEDTLS_SSL_EARLY_DATA_STATUS_NOT_SENT;
+#endif
+
     /* Initialize structures */
     mbedtls_ssl_session_init(ssl->session_negotiate);
     ssl_handshake_params_init(ssl->handshake);
diff --git a/library/ssl_tls13_server.c b/library/ssl_tls13_server.c
index 904bb5b..8bd70ef 100644
--- a/library/ssl_tls13_server.c
+++ b/library/ssl_tls13_server.c
@@ -1780,7 +1780,8 @@
 }
 
 #if defined(MBEDTLS_SSL_EARLY_DATA)
-static void ssl_tls13_update_early_data_status(mbedtls_ssl_context *ssl)
+static int ssl_tls13_is_early_data_accepted(mbedtls_ssl_context *ssl,
+                                            int hrr_required)
 {
     mbedtls_ssl_handshake_params *handshake = ssl->handshake;
 
@@ -1788,17 +1789,19 @@
          MBEDTLS_SSL_EXT_MASK(EARLY_DATA)) == 0) {
         MBEDTLS_SSL_DEBUG_MSG(
             1, ("EarlyData: no early data extension received."));
-        ssl->early_data_status = MBEDTLS_SSL_EARLY_DATA_STATUS_NOT_RECEIVED;
-        return;
+        return 0;
     }
 
-    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;
+        return 0;
+    }
+
+    if (hrr_required) {
+        MBEDTLS_SSL_DEBUG_MSG(1, ("EarlyData: rejected, HRR required."));
+        return 0;
     }
 
     if (!handshake->resume) {
@@ -1807,7 +1810,7 @@
            resumption. */
         MBEDTLS_SSL_DEBUG_MSG(
             1, ("EarlyData: rejected, not a session resumption."));
-        return;
+        return 0;
     }
 
     /* RFC 8446 4.2.10
@@ -1830,7 +1833,7 @@
         MBEDTLS_SSL_DEBUG_MSG(
             1, ("EarlyData: rejected, the selected key in "
                 "`pre_shared_key` is not the first one."));
-        return;
+        return 0;
     }
 
     if (handshake->ciphersuite_info->id !=
@@ -1838,7 +1841,7 @@
         MBEDTLS_SSL_DEBUG_MSG(
             1, ("EarlyData: rejected, the selected ciphersuite is not the one "
                 "of the selected pre-shared key."));
-        return;
+        return 0;
 
     }
 
@@ -1847,18 +1850,18 @@
             1,
             ("EarlyData: rejected, early_data not allowed in ticket "
              "permission bits."));
-        return;
+        return 0;
     }
 
-    ssl->early_data_status = MBEDTLS_SSL_EARLY_DATA_STATUS_ACCEPTED;
-
+    return 1;
 }
 #endif /* MBEDTLS_SSL_EARLY_DATA */
 
 /* Update the handshake state machine */
 
 MBEDTLS_CHECK_RETURN_CRITICAL
-static int ssl_tls13_postprocess_client_hello(mbedtls_ssl_context *ssl)
+static int ssl_tls13_postprocess_client_hello(mbedtls_ssl_context *ssl,
+                                              int hrr_required)
 {
     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
 
@@ -1882,10 +1885,10 @@
     }
 
 #if defined(MBEDTLS_SSL_EARLY_DATA)
-    /* There is enough information, update early data state. */
-    ssl_tls13_update_early_data_status(ssl);
+    ssl->handshake->early_data_accepted =
+        ssl_tls13_is_early_data_accepted(ssl, hrr_required);
 
-    if (ssl->early_data_status == MBEDTLS_SSL_EARLY_DATA_STATUS_ACCEPTED) {
+    if (ssl->handshake->early_data_accepted) {
         ret = mbedtls_ssl_tls13_compute_early_transform(ssl);
         if (ret != 0) {
             MBEDTLS_SSL_DEBUG_RET(
@@ -1893,6 +1896,8 @@
             return ret;
         }
     }
+#else
+    ((void) hrr_required);
 #endif /* MBEDTLS_SSL_EARLY_DATA */
 
     return 0;
@@ -1947,7 +1952,9 @@
         return 0;
     }
 
-    MBEDTLS_SSL_PROC_CHK(ssl_tls13_postprocess_client_hello(ssl));
+    MBEDTLS_SSL_PROC_CHK(
+        ssl_tls13_postprocess_client_hello(ssl, parse_client_hello_ret ==
+                                           SSL_CLIENT_HELLO_HRR_REQUIRED));
 
     if (SSL_CLIENT_HELLO_OK == parse_client_hello_ret) {
         mbedtls_ssl_handshake_set_state(ssl, MBEDTLS_SSL_SERVER_HELLO);
@@ -2530,7 +2537,7 @@
 #endif /* MBEDTLS_SSL_ALPN */
 
 #if defined(MBEDTLS_SSL_EARLY_DATA)
-    if (ssl->early_data_status == MBEDTLS_SSL_EARLY_DATA_STATUS_ACCEPTED) {
+    if (ssl->handshake->early_data_accepted) {
         ret = mbedtls_ssl_tls13_write_early_data_ext(
             ssl, 0, p, end, &output_len);
         if (ret != 0) {
@@ -2857,7 +2864,7 @@
     }
 
 #if defined(MBEDTLS_SSL_EARLY_DATA)
-    if (ssl->early_data_status == MBEDTLS_SSL_EARLY_DATA_STATUS_ACCEPTED) {
+    if (ssl->handshake->early_data_accepted) {
         /* See RFC 8446 section A.2 for more information */
         MBEDTLS_SSL_DEBUG_MSG(
             1, ("Switch to early keys for inbound traffic. "
@@ -2911,6 +2918,17 @@
 
     if (ssl->in_msgtype == MBEDTLS_SSL_MSG_APPLICATION_DATA) {
         MBEDTLS_SSL_DEBUG_MSG(3, ("Received early data"));
+        /* RFC 8446 section 4.6.1
+         *
+         * A server receiving more than max_early_data_size bytes of 0-RTT data
+         * SHOULD terminate the connection with an "unexpected_message" alert.
+         *
+         * TODO: Add received data size check here.
+         */
+        if (ssl->in_offt == NULL) {
+            /* Set the reading pointer */
+            ssl->in_offt = ssl->in_msg;
+        }
         return SSL_GOT_EARLY_DATA;
     }
 
@@ -2936,37 +2954,6 @@
     return 0;
 }
 
-MBEDTLS_CHECK_RETURN_CRITICAL
-static int ssl_tls13_process_early_application_data(mbedtls_ssl_context *ssl)
-{
-    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
-
-    if ((ret = mbedtls_ssl_read_record(ssl, 0)) != 0) {
-        MBEDTLS_SSL_DEBUG_RET(1, "mbedtls_ssl_read_record", ret);
-        return ret;
-    }
-
-    /*
-     * Output early data
-     *
-     * For the time being, we print received data via debug message.
-     *
-     * TODO: Remove it when `mbedtls_ssl_read_early_data` is ready.
-     */
-    ssl->in_msg[ssl->in_msglen] = 0;
-    MBEDTLS_SSL_DEBUG_MSG(3, ("\n%s", ssl->in_msg));
-
-    /* RFC 8446 section 4.6.1
-     *
-     * A server receiving more than max_early_data_size bytes of 0-RTT data
-     * SHOULD terminate the connection with an "unexpected_message" alert.
-     *
-     * TODO: Add received data size check here.
-     */
-
-    return 0;
-}
-
 /*
  * RFC 8446 section A.2
  *
@@ -3037,7 +3024,8 @@
         ssl_tls13_prepare_for_handshake_second_flight(ssl);
 
     } else if (ret == SSL_GOT_EARLY_DATA) {
-        MBEDTLS_SSL_PROC_CHK(ssl_tls13_process_early_application_data(ssl));
+        ret = MBEDTLS_ERR_SSL_RECEIVED_EARLY_DATA;
+        goto cleanup;
     } else {
         MBEDTLS_SSL_DEBUG_MSG(1, ("should never happen"));
         ret = MBEDTLS_ERR_SSL_INTERNAL_ERROR;
diff --git a/programs/ssl/ssl_server2.c b/programs/ssl/ssl_server2.c
index 598d38c..48b2282 100644
--- a/programs/ssl/ssl_server2.c
+++ b/programs/ssl/ssl_server2.c
@@ -1612,6 +1612,7 @@
 #if defined(MBEDTLS_SSL_EARLY_DATA)
     int tls13_early_data_enabled = MBEDTLS_SSL_EARLY_DATA_DISABLED;
 #endif
+
 #if defined(MBEDTLS_MEMORY_BUFFER_ALLOC_C)
     mbedtls_memory_buffer_alloc_init(alloc_buf, sizeof(alloc_buf));
 #if defined(MBEDTLS_MEMORY_DEBUG)
@@ -3450,6 +3451,19 @@
     fflush(stdout);
 
     while ((ret = mbedtls_ssl_handshake(&ssl)) != 0) {
+#if defined(MBEDTLS_SSL_EARLY_DATA)
+        if (ret == MBEDTLS_ERR_SSL_RECEIVED_EARLY_DATA) {
+            memset(buf, 0, opt.buffer_size);
+            ret = mbedtls_ssl_read_early_data(&ssl, buf, opt.buffer_size);
+            if (ret > 0) {
+                buf[ret] = '\0';
+                mbedtls_printf(" %d early data bytes read\n\n%s\n",
+                               ret, (char *) buf);
+            }
+            continue;
+        }
+#endif /* MBEDTLS_SSL_EARLY_DATA */
+
 #if defined(MBEDTLS_SSL_ASYNC_PRIVATE)
         if (ret == MBEDTLS_ERR_SSL_ASYNC_IN_PROGRESS &&
             ssl_async_keys.inject_error == SSL_ASYNC_INJECT_ERROR_CANCEL) {
diff --git a/tests/data_files/tls13_early_data.txt b/tests/data_files/tls13_early_data.txt
index 0c84b07..95811fd 100644
--- a/tests/data_files/tls13_early_data.txt
+++ b/tests/data_files/tls13_early_data.txt
@@ -1,3 +1,4 @@
 EarlyData context: line 0                                                    lf
 EarlyData context: line 1                                                    lf
+EarlyData context: line 2                                                    lf
 EarlyData context: If it appears, that means early_data received.
diff --git a/tests/opt-testcases/tls13-misc.sh b/tests/opt-testcases/tls13-misc.sh
index c1682e3..b6894de 100755
--- a/tests/opt-testcases/tls13-misc.sh
+++ b/tests/opt-testcases/tls13-misc.sh
@@ -506,4 +506,7 @@
          -s "Sent max_early_data_size=$EARLY_DATA_INPUT_LEN"                \
          -s "ClientHello: early_data(42) extension exists."                 \
          -s "EncryptedExtensions: early_data(42) extension exists."         \
-         -s "$( tail -1 $EARLY_DATA_INPUT )"
+         -s "$( head -1 $EARLY_DATA_INPUT )"                                \
+         -s "$( tail -1 $EARLY_DATA_INPUT )"                                \
+         -s "200 early data bytes read"                                     \
+         -s "106 early data bytes read"
diff --git a/tests/suites/test_suite_ssl.function b/tests/suites/test_suite_ssl.function
index d26407e..2d1a757 100644
--- a/tests/suites/test_suite_ssl.function
+++ b/tests/suites/test_suite_ssl.function
@@ -12,8 +12,7 @@
 
 #define SSL_MESSAGE_QUEUE_INIT      { NULL, 0, 0, 0 }
 
-#if (!defined(MBEDTLS_SSL_PROTO_TLS1_2)) && \
-    defined(MBEDTLS_SSL_EARLY_DATA) && defined(MBEDTLS_SSL_CLI_C) && \
+#if defined(MBEDTLS_SSL_EARLY_DATA) && defined(MBEDTLS_SSL_CLI_C) && \
     defined(MBEDTLS_SSL_SRV_C) && defined(MBEDTLS_DEBUG_C) && \
     defined(MBEDTLS_TEST_AT_LEAST_ONE_TLS1_3_CIPHERSUITE) && \
     defined(MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL_ENABLED) && \
@@ -3662,12 +3661,7 @@
 }
 /* END_CASE */
 
-/*
- * The !MBEDTLS_SSL_PROTO_TLS1_2 dependency of tls13_early_data() below is
- * a temporary workaround to not run the test in Windows-2013 where there is
- * an issue with mbedtls_vsnprintf().
- */
-/* BEGIN_CASE depends_on:!MBEDTLS_SSL_PROTO_TLS1_2:MBEDTLS_SSL_EARLY_DATA:MBEDTLS_SSL_CLI_C:MBEDTLS_SSL_SRV_C:MBEDTLS_DEBUG_C:MBEDTLS_TEST_AT_LEAST_ONE_TLS1_3_CIPHERSUITE:MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL_ENABLED:MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL_ENABLED:MBEDTLS_MD_CAN_SHA256:MBEDTLS_ECP_HAVE_SECP256R1:MBEDTLS_ECP_HAVE_SECP384R1:MBEDTLS_PK_CAN_ECDSA_VERIFY:MBEDTLS_SSL_SESSION_TICKETS */
+/* BEGIN_CASE depends_on:MBEDTLS_SSL_EARLY_DATA:MBEDTLS_SSL_CLI_C:MBEDTLS_SSL_SRV_C:MBEDTLS_DEBUG_C:MBEDTLS_TEST_AT_LEAST_ONE_TLS1_3_CIPHERSUITE:MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_EPHEMERAL_ENABLED:MBEDTLS_SSL_TLS1_3_KEY_EXCHANGE_MODE_PSK_EPHEMERAL_ENABLED:MBEDTLS_MD_CAN_SHA256:MBEDTLS_ECP_HAVE_SECP256R1:MBEDTLS_ECP_HAVE_SECP384R1:MBEDTLS_PK_CAN_ECDSA_VERIFY:MBEDTLS_SSL_SESSION_TICKETS */
 void tls13_early_data()
 {
     int ret = -1;
@@ -3678,7 +3672,6 @@
     mbedtls_test_handshake_test_options client_options;
     mbedtls_test_handshake_test_options server_options;
     mbedtls_ssl_session saved_session;
-    mbedtls_test_ssl_log_pattern server_pattern = { NULL, 0 };
 
     /*
      * Test set-up
@@ -3699,9 +3692,6 @@
     mbedtls_ssl_conf_early_data(&client_ep.conf, MBEDTLS_SSL_EARLY_DATA_ENABLED);
 
     server_options.pk_alg = MBEDTLS_PK_ECDSA;
-    server_options.srv_log_fun = mbedtls_test_ssl_log_analyzer;
-    server_options.srv_log_obj = &server_pattern;
-    server_pattern.pattern = early_data;
     ret = mbedtls_test_ssl_endpoint_init(&server_ep, MBEDTLS_SSL_IS_SERVER,
                                          &server_options, NULL, NULL, NULL,
                                          NULL);
@@ -3750,15 +3740,12 @@
     ret = mbedtls_ssl_set_session(&(client_ep.ssl), &saved_session);
     TEST_EQUAL(ret, 0);
 
-    mbedtls_debug_set_threshold(3);
-
     TEST_EQUAL(mbedtls_test_move_handshake_to_state(
                    &(client_ep.ssl), &(server_ep.ssl),
                    MBEDTLS_SSL_SERVER_HELLO), 0);
 
     TEST_ASSERT(client_ep.ssl.early_data_status !=
                 MBEDTLS_SSL_EARLY_DATA_STATUS_NOT_SENT);
-    TEST_EQUAL(server_pattern.counter, 0);
 
     ret = write_early_data(&(client_ep.ssl), (unsigned char *) early_data,
                            early_data_len);
@@ -3766,11 +3753,16 @@
 
     TEST_EQUAL(mbedtls_test_move_handshake_to_state(
                    &(server_ep.ssl), &(client_ep.ssl),
-                   MBEDTLS_SSL_CLIENT_FINISHED), 0);
+                   MBEDTLS_SSL_CLIENT_FINISHED), MBEDTLS_ERR_SSL_RECEIVED_EARLY_DATA);
 
-    TEST_EQUAL(server_ep.ssl.early_data_status,
-               MBEDTLS_SSL_EARLY_DATA_STATUS_ACCEPTED);
-    TEST_EQUAL(server_pattern.counter, 1);
+    TEST_EQUAL(server_ep.ssl.handshake->early_data_accepted, 1);
+    TEST_EQUAL(mbedtls_ssl_read_early_data(&(server_ep.ssl), buf, sizeof(buf)),
+               early_data_len);
+    TEST_MEMORY_COMPARE(buf, early_data_len, early_data, early_data_len);
+
+    TEST_EQUAL(mbedtls_test_move_handshake_to_state(
+                   &(server_ep.ssl), &(client_ep.ssl),
+                   MBEDTLS_SSL_HANDSHAKE_OVER), 0);
 
 exit:
     mbedtls_test_ssl_endpoint_free(&client_ep, NULL);
@@ -3778,7 +3770,6 @@
     mbedtls_test_free_handshake_options(&client_options);
     mbedtls_test_free_handshake_options(&server_options);
     mbedtls_ssl_session_free(&saved_session);
-    mbedtls_debug_set_threshold(0);
     PSA_DONE();
 }
 /* END_CASE */