diff --git a/ChangeLog.d/fix-ssl-session-serialization-config.txt b/ChangeLog.d/fix-ssl-session-serialization-config.txt
new file mode 100644
index 0000000..ca1cc81
--- /dev/null
+++ b/ChangeLog.d/fix-ssl-session-serialization-config.txt
@@ -0,0 +1,4 @@
+Bugfix
+   * Fix missing bitflags in SSL session serialization headers. Their absence
+     allowed SSL sessions saved in one configuration to be loaded in a
+     different, incompatible configuration.
diff --git a/include/mbedtls/ecp.h b/include/mbedtls/ecp.h
index e4e40c0..33ea14d 100644
--- a/include/mbedtls/ecp.h
+++ b/include/mbedtls/ecp.h
@@ -1265,6 +1265,8 @@
 /**
  * \brief           This function reads an elliptic curve private key.
  *
+ * \note            This function does not support Curve448 yet.
+ *
  * \param grp_id    The ECP group identifier.
  * \param key       The destination key.
  * \param buf       The buffer containing the binary representation of the
@@ -1286,17 +1288,43 @@
 /**
  * \brief           This function exports an elliptic curve private key.
  *
+ * \note            Note that although this function accepts an output
+ *                  buffer that is smaller or larger than the key, most key
+ *                  import interfaces require the output to have exactly
+ *                  key's nominal length. It is generally simplest to
+ *                  pass the key's nominal length as \c buflen, after
+ *                  checking that the output buffer is large enough.
+ *                  See the description of the \p buflen parameter for
+ *                  how to calculate the nominal length.
+ *
+ * \note            If the private key was not set in \p key,
+ *                  the output is unspecified. Future versions
+ *                  may return an error in that case.
+ *
+ * \note            This function does not support Curve448 yet.
+ *
  * \param key       The private key.
  * \param buf       The output buffer for containing the binary representation
- *                  of the key. (Big endian integer for Weierstrass curves, byte
- *                  string for Montgomery curves.)
+ *                  of the key.
+ *                  For Weierstrass curves, this is the big-endian
+ *                  representation, padded with null bytes at the beginning
+ *                  to reach \p buflen bytes.
+ *                  For Montgomery curves, this is the standard byte string
+ *                  representation (which is little-endian), padded with
+ *                  null bytes at the end to reach \p buflen bytes.
  * \param buflen    The total length of the buffer in bytes.
+ *                  The length of the output is
+ *                  (`grp->nbits` + 7) / 8 bytes
+ *                  where `grp->nbits` is the private key size in bits.
+ *                  For Weierstrass keys, if the output buffer is smaller,
+ *                  leading zeros are trimmed to fit if possible. For
+ *                  Montgomery keys, the output buffer must always be large
+ *                  enough for the nominal length.
  *
  * \return          \c 0 on success.
- * \return          #MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL if the \p key
-                    representation is larger than the available space in \p buf.
- * \return          #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE if the operation for
- *                  the group is not implemented.
+ * \return          #MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL or
+ *                  #MBEDTLS_ERR_MPI_BUFFER_TOO_SMALL if the \p key
+ *                  representation is larger than the available space in \p buf.
  * \return          Another negative error code on different kinds of failure.
  */
 int mbedtls_ecp_write_key(mbedtls_ecp_keypair *key,
diff --git a/include/psa/crypto_values.h b/include/psa/crypto_values.h
index b528251..773c01e 100644
--- a/include/psa/crypto_values.h
+++ b/include/psa/crypto_values.h
@@ -400,7 +400,7 @@
     ((type) | PSA_KEY_TYPE_CATEGORY_FLAG_PAIR)
 /** The public key type corresponding to a key pair type.
  *
- * You may also pass a key pair type as \p type, it will be left unchanged.
+ * You may also pass a public key type as \p type, it will be left unchanged.
  *
  * \param type      A public key type or key pair type.
  *
diff --git a/library/ecp.c b/library/ecp.c
index f67b4d0..cfe02b0 100644
--- a/library/ecp.c
+++ b/library/ecp.c
@@ -927,7 +927,7 @@
     size_t plen;
     ECP_VALIDATE_RET(grp != NULL);
     ECP_VALIDATE_RET(pt  != NULL);
-    ECP_VALIDATE_RET(buf != NULL);
+    ECP_VALIDATE_RET(ilen == 0 || buf != NULL);
 
     if (ilen < 1) {
         return MBEDTLS_ERR_ECP_BAD_INPUT_DATA;
@@ -996,7 +996,7 @@
     ECP_VALIDATE_RET(grp != NULL);
     ECP_VALIDATE_RET(pt  != NULL);
     ECP_VALIDATE_RET(buf != NULL);
-    ECP_VALIDATE_RET(*buf != NULL);
+    ECP_VALIDATE_RET(buf_len == 0 || *buf != NULL);
 
     /*
      * We must have at least two bytes (1 for length, at least one for data)
@@ -1068,7 +1068,7 @@
     mbedtls_ecp_group_id grp_id;
     ECP_VALIDATE_RET(grp  != NULL);
     ECP_VALIDATE_RET(buf  != NULL);
-    ECP_VALIDATE_RET(*buf != NULL);
+    ECP_VALIDATE_RET(len == 0 || *buf != NULL);
 
     if ((ret = mbedtls_ecp_tls_read_group_id(&grp_id, buf, len)) != 0) {
         return ret;
@@ -1088,7 +1088,7 @@
     const mbedtls_ecp_curve_info *curve_info;
     ECP_VALIDATE_RET(grp  != NULL);
     ECP_VALIDATE_RET(buf  != NULL);
-    ECP_VALIDATE_RET(*buf != NULL);
+    ECP_VALIDATE_RET(len == 0 || *buf != NULL);
 
     /*
      * We expect at least three bytes (see below)
@@ -3358,10 +3358,10 @@
 int mbedtls_ecp_write_key(mbedtls_ecp_keypair *key,
                           unsigned char *buf, size_t buflen)
 {
-    int ret = MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE;
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
 
     ECP_VALIDATE_RET(key != NULL);
-    ECP_VALIDATE_RET(buf != NULL);
+    ECP_VALIDATE_RET(buflen == 0 || buf != NULL);
 
 #if defined(MBEDTLS_ECP_MONTGOMERY_ENABLED)
     if (mbedtls_ecp_get_type(&key->grp) == MBEDTLS_ECP_TYPE_MONTGOMERY) {
diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index fc8e8c6..235959a 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -5204,6 +5204,12 @@
 #define SSL_SERIALIZED_SESSION_CONFIG_CRT 0
 #endif /* MBEDTLS_X509_CRT_PARSE_C */
 
+#if defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
+#define SSL_SERIALIZED_SESSION_CONFIG_KEEP_PEER_CRT 1
+#else
+#define SSL_SERIALIZED_SESSION_CONFIG_KEEP_PEER_CRT 0
+#endif /* MBEDTLS_SSL_SESSION_TICKETS */
+
 #if defined(MBEDTLS_SSL_CLI_C) && defined(MBEDTLS_SSL_SESSION_TICKETS)
 #define SSL_SERIALIZED_SESSION_CONFIG_CLIENT_TICKET 1
 #else
@@ -5241,6 +5247,7 @@
 #define SSL_SERIALIZED_SESSION_CONFIG_TRUNC_HMAC_BIT    4
 #define SSL_SERIALIZED_SESSION_CONFIG_ETM_BIT           5
 #define SSL_SERIALIZED_SESSION_CONFIG_TICKET_BIT        6
+#define SSL_SERIALIZED_SESSION_CONFIG_KEEP_PEER_CRT_BIT 7
 
 #define SSL_SERIALIZED_SESSION_CONFIG_BITFLAG                           \
     ((uint16_t) (                                                      \
@@ -5252,7 +5259,9 @@
          (SSL_SERIALIZED_SESSION_CONFIG_TRUNC_HMAC << \
              SSL_SERIALIZED_SESSION_CONFIG_TRUNC_HMAC_BIT) | \
          (SSL_SERIALIZED_SESSION_CONFIG_ETM << SSL_SERIALIZED_SESSION_CONFIG_ETM_BIT) | \
-         (SSL_SERIALIZED_SESSION_CONFIG_TICKET << SSL_SERIALIZED_SESSION_CONFIG_TICKET_BIT)))
+         (SSL_SERIALIZED_SESSION_CONFIG_TICKET << SSL_SERIALIZED_SESSION_CONFIG_TICKET_BIT) | \
+         (SSL_SERIALIZED_SESSION_CONFIG_KEEP_PEER_CRT << \
+             SSL_SERIALIZED_SESSION_CONFIG_KEEP_PEER_CRT_BIT)))
 
 static const unsigned char ssl_serialized_session_header[] = {
     MBEDTLS_VERSION_MAJOR,
@@ -5278,19 +5287,36 @@
  *                               // the setting of those compile-time
  *                               // configuration options which influence
  *                               // the structure of mbedtls_ssl_session.
- *  uint64 start_time;
- *  uint8 ciphersuite[2];        // defined by the standard
- *  uint8 compression;           // 0 or 1
- *  uint8 session_id_len;        // at most 32
- *  opaque session_id[32];
- *  opaque master[48];           // fixed length in the standard
- *  uint32 verify_result;
- *  opaque peer_cert<0..2^24-1>; // length 0 means no peer cert
- *  opaque ticket<0..2^24-1>;    // length 0 means no ticket
- *  uint32 ticket_lifetime;
- *  uint8 mfl_code;              // up to 255 according to standard
- *  uint8 trunc_hmac;            // 0 or 1
- *  uint8 encrypt_then_mac;      // 0 or 1
+ * #if defined(MBEDTLS_HAVE_TIME)
+ *     uint64 start_time;
+ * #endif
+ *     uint8 ciphersuite[2];        // defined by the standard
+ *     uint8 compression;           // 0 or 1
+ *     uint8 session_id_len;        // at most 32
+ *     opaque session_id[32];
+ *     opaque master[48];           // fixed length in the standard
+ *     uint32 verify_result;
+ * #if defined(MBEDTLS_X509_CRT_PARSE_C)
+ * #if defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
+ *     opaque peer_cert<0..2^24-1>; // length 0 means no peer cert
+ * #else
+ *     uint8 peer_cert_digest_type;
+ *     opaque peer_cert_digest<0..2^8-1>
+ * #endif
+ * #endif
+ * #if defined(MBEDTLS_SSL_SESSION_TICKETS) && defined(MBEDTLS_SSL_CLI_C)
+ *     opaque ticket<0..2^24-1>;    // length 0 means no ticket
+ *     uint32 ticket_lifetime;
+ * #endif
+ * #if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
+ *     uint8 mfl_code;              // up to 255 according to standard
+ * #endif
+ * #if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
+ *     uint8 trunc_hmac;            // 0 or 1
+ * #endif
+ * #if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
+ *     uint8 encrypt_then_mac;      // 0 or 1
+ * #endif
  *
  * The order is the same as in the definition of the structure, except
  * verify_result is put before peer_cert so that all mandatory fields come
diff --git a/scripts/generate_visualc_files.pl b/scripts/generate_visualc_files.pl
index 11604cd..b27f795 100755
--- a/scripts/generate_visualc_files.pl
+++ b/scripts/generate_visualc_files.pl
@@ -168,7 +168,7 @@
 }
 
 sub get_app_list {
-    my $app_list = `cd $programs_dir && make list`;
+    my $app_list = `cd $programs_dir && VERBOSE_LOGS=1 make list`;
     die "make list failed: $!\n" if $?;
 
     return split /\s+/, $app_list;
diff --git a/tests/scripts/all.sh b/tests/scripts/all.sh
index ca2df4d..01ce3b9 100755
--- a/tests/scripts/all.sh
+++ b/tests/scripts/all.sh
@@ -195,10 +195,21 @@
     # defined in this script whose name starts with "component_".
     ALL_COMPONENTS=$(compgen -A function component_ | sed 's/component_//')
 
-    # Delay determinig SUPPORTED_COMPONENTS until the command line options have a chance to override
+    # Delay determining SUPPORTED_COMPONENTS until the command line options have a chance to override
     # the commands set by the environment
 }
 
+setup_quiet_wrappers()
+{
+    # Pick up "quiet" wrappers for make and cmake, which don't output very much
+    # unless there is an error. This reduces logging overhead in the CI.
+    #
+    # Note that the cmake wrapper breaks unless we use an absolute path here.
+    if [[ -e ${PWD}/tests/scripts/quiet ]]; then
+        export PATH=${PWD}/tests/scripts/quiet:$PATH
+    fi
+}
+
 # Test whether the component $1 is included in the command line patterns.
 is_component_included()
 {
@@ -997,6 +1008,9 @@
 }
 
 component_test_zlib_cmake() {
+    # This is needed due to something parsing the output from make
+    export VERBOSE_LOGS=1
+
     msg "build: zlib enabled, cmake"
     scripts/config.py set MBEDTLS_ZLIB_SUPPORT
     cmake -D ENABLE_ZLIB_SUPPORT=On -D CMAKE_BUILD_TYPE:String=Release .
@@ -3733,6 +3747,7 @@
 pre_initialize_variables
 pre_parse_command_line "$@"
 
+setup_quiet_wrappers
 pre_check_git
 pre_restore_files
 pre_back_up
diff --git a/tests/scripts/check_files.py b/tests/scripts/check_files.py
index a2a9dfa..837905e 100755
--- a/tests/scripts/check_files.py
+++ b/tests/scripts/check_files.py
@@ -172,6 +172,8 @@
         b'sh': 'sh',
     }
 
+    path_exemptions = re.compile(r'tests/scripts/quiet/.*')
+
     def is_valid_shebang(self, first_line, filepath):
         m = re.match(self._shebang_re, first_line)
         if not m:
diff --git a/tests/scripts/depends.py b/tests/scripts/depends.py
index c6a438e..346f6ff 100755
--- a/tests/scripts/depends.py
+++ b/tests/scripts/depends.py
@@ -192,7 +192,10 @@
         success = True
         for command in self.commands:
             log_command(command)
-            ret = subprocess.call(command)
+            env = os.environ.copy()
+            if 'MBEDTLS_TEST_CONFIGURATION' in env:
+                env['MBEDTLS_TEST_CONFIGURATION'] += '-' + self.name
+            ret = subprocess.call(command, env=env)
             if ret != 0:
                 if command[0] not in ['make', options.make_command]:
                     log_line('*** [{}] Error {}'.format(' '.join(command), ret))
diff --git a/tests/scripts/quiet/cmake b/tests/scripts/quiet/cmake
new file mode 100755
index 0000000..930931d
--- /dev/null
+++ b/tests/scripts/quiet/cmake
@@ -0,0 +1,19 @@
+#! /usr/bin/env bash
+#
+# Copyright The Mbed TLS Contributors
+# SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
+#
+# This swallows the output of the wrapped tool, unless there is an error.
+# This helps reduce excess logging in the CI.
+
+# If you are debugging a build / CI issue, you can get complete unsilenced logs
+# by un-commenting the following line (or setting VERBOSE_LOGS in your environment):
+
+# export VERBOSE_LOGS=1
+
+# don't silence invocations containing these arguments
+export NO_SILENCE=" --version "
+
+export TOOL="cmake"
+
+exec "$(dirname "$0")/quiet.sh" "$@"
diff --git a/tests/scripts/quiet/make b/tests/scripts/quiet/make
new file mode 100755
index 0000000..d022551
--- /dev/null
+++ b/tests/scripts/quiet/make
@@ -0,0 +1,19 @@
+#! /usr/bin/env bash
+#
+# Copyright The Mbed TLS Contributors
+# SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
+#
+# This swallows the output of the wrapped tool, unless there is an error.
+# This helps reduce excess logging in the CI.
+
+# If you are debugging a build / CI issue, you can get complete unsilenced logs
+# by un-commenting the following line (or setting VERBOSE_LOGS in your environment):
+
+# export VERBOSE_LOGS=1
+
+# don't silence invocations containing these arguments
+export NO_SILENCE=" --version | test "
+
+export TOOL="make"
+
+exec "$(dirname "$0")/quiet.sh" "$@"
diff --git a/tests/scripts/quiet/quiet.sh b/tests/scripts/quiet/quiet.sh
new file mode 100755
index 0000000..30ee569
--- /dev/null
+++ b/tests/scripts/quiet/quiet.sh
@@ -0,0 +1,75 @@
+# -*-mode: sh; sh-shell: bash -*-
+#
+# Copyright The Mbed TLS Contributors
+# SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
+#
+# This swallows the output of the wrapped tool, unless there is an error.
+# This helps reduce excess logging in the CI.
+
+# If you are debugging a build / CI issue, you can get complete unsilenced logs
+# by un-commenting the following line (or setting VERBOSE_LOGS in your environment):
+#
+# VERBOSE_LOGS=1
+#
+# This script provides most of the functionality for the adjacent make and cmake
+# wrappers.
+#
+# It requires two variables to be set:
+#
+# TOOL       - the name of the tool that is being wrapped (with no path), e.g. "make"
+#
+# NO_SILENCE - a regex that describes the commandline arguments for which output will not
+#              be silenced, e.g. " --version | test ". In this example, "make lib test" will
+#              not be silent, but "make lib" will be.
+
+# Locate original tool
+TOOL_WITH_PATH=$(dirname "$0")/$TOOL
+ORIGINAL_TOOL=$(type -ap "${TOOL}" | grep -v -Fx "$TOOL_WITH_PATH" | head -n1)
+
+print_quoted_args() {
+    # similar to printf '%q' "$@"
+    # but produce more human-readable results for common/simple cases like "a b"
+    for a in "$@"; do
+        # Get bash to quote the string
+        printf -v q '%q' "$a"
+        simple_pattern="^([-[:alnum:]_+./:@]+=)?([^']*)$"
+        if [[ "$a" != "$q" && $a =~ $simple_pattern ]]; then
+            # a requires some quoting (a != q), but has no single quotes, so we can
+            # simplify the quoted form - e.g.:
+            #   a b        -> 'a b'
+            #   CFLAGS=a b -> CFLAGS='a b'
+            q="${BASH_REMATCH[1]}'${BASH_REMATCH[2]}'"
+        fi
+        printf " %s" "$q"
+    done
+}
+
+if [[ ! " $* " =~ " --version " ]]; then
+    # Display the command being invoked - if it succeeds, this is all that will
+    # be displayed. Don't do this for invocations with --version, because
+    # this output is often parsed by scripts, so we don't want to modify it.
+    printf %s "${TOOL}"    1>&2
+    print_quoted_args "$@" 1>&2
+    echo                   1>&2
+fi
+
+if [[ " $@ " =~ $NO_SILENCE || -n "${VERBOSE_LOGS}" ]]; then
+    # Run original command with no output supression
+    exec "${ORIGINAL_TOOL}" "$@"
+else
+    # Run original command and capture output & exit status
+    TMPFILE=$(mktemp "quiet-${TOOL}.XXXXXX")
+    "${ORIGINAL_TOOL}" "$@" > "${TMPFILE}" 2>&1
+    EXIT_STATUS=$?
+
+    if [[ $EXIT_STATUS -ne 0 ]]; then
+        # On error, display the full output
+        cat "${TMPFILE}"
+    fi
+
+    # Remove tmpfile
+    rm "${TMPFILE}"
+
+    # Propagate the exit status
+    exit $EXIT_STATUS
+fi
diff --git a/tests/suites/test_suite_ecp.data b/tests/suites/test_suite_ecp.data
index 6211fb7..a244bc4 100644
--- a/tests/suites/test_suite_ecp.data
+++ b/tests/suites/test_suite_ecp.data
@@ -550,6 +550,122 @@
 depends_on:MBEDTLS_ECP_DP_CURVE25519_ENABLED
 mbedtls_ecp_read_key:MBEDTLS_ECP_DP_CURVE25519:"70076d0a7318a57d3c16c17251b26645df4c2f87ebc0992ab177fba51db92c6a":0:1
 
+ECP write key: secp256r1, nominal
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecp_write_key:MBEDTLS_ECP_DP_SECP256R1:"f12a1320760270a83cbffd53f6031ef76a5d86c8a204f2c30ca9ebf51f0f0ea7":32:0
+
+ECP write key: secp256r1, output longer by 1
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecp_write_key:MBEDTLS_ECP_DP_SECP256R1:"f12a1320760270a83cbffd53f6031ef76a5d86c8a204f2c30ca9ebf51f0f0ea7":33:0
+
+ECP write key: secp256r1, output longer by 32
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecp_write_key:MBEDTLS_ECP_DP_SECP256R1:"f12a1320760270a83cbffd53f6031ef76a5d86c8a204f2c30ca9ebf51f0f0ea7":64:0
+
+ECP write key: secp256r1, output longer by 33
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecp_write_key:MBEDTLS_ECP_DP_SECP256R1:"f12a1320760270a83cbffd53f6031ef76a5d86c8a204f2c30ca9ebf51f0f0ea7":65:0
+
+ECP write key: secp256r1, output short by 1
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecp_write_key:MBEDTLS_ECP_DP_SECP256R1:"f12a1320760270a83cbffd53f6031ef76a5d86c8a204f2c30ca9ebf51f0f0ea7":31:MBEDTLS_ERR_MPI_BUFFER_TOO_SMALL
+
+ECP write key: secp256r1, output_size=1
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecp_write_key:MBEDTLS_ECP_DP_SECP256R1:"f12a1320760270a83cbffd53f6031ef76a5d86c8a204f2c30ca9ebf51f0f0ea7":1:MBEDTLS_ERR_MPI_BUFFER_TOO_SMALL
+
+ECP write key: secp256r1, output_size=0
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecp_write_key:MBEDTLS_ECP_DP_SECP256R1:"f12a1320760270a83cbffd53f6031ef76a5d86c8a204f2c30ca9ebf51f0f0ea7":0:MBEDTLS_ERR_MPI_BUFFER_TOO_SMALL
+
+ECP write key: secp256r1, top byte = 0, output_size=32
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecp_write_key:MBEDTLS_ECP_DP_SECP256R1:"00ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff":32:0
+
+ECP write key: secp256r1, top byte = 0, output_size=31 (fits)
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecp_write_key:MBEDTLS_ECP_DP_SECP256R1:"00ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff":31:0
+
+ECP write key: secp256r1, top byte = 0, output_size=30 (too small)
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecp_write_key:MBEDTLS_ECP_DP_SECP256R1:"00ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff":30:MBEDTLS_ERR_MPI_BUFFER_TOO_SMALL
+
+ECP write key: secp256r1, mostly-0 key, output_size=32
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecp_write_key:MBEDTLS_ECP_DP_SECP256R1:"0000000000000000000000000000000000000000000000000000000000000001":32:0
+
+ECP write key: secp256r1, mostly-0 key, output_size=31 (fits)
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecp_write_key:MBEDTLS_ECP_DP_SECP256R1:"0000000000000000000000000000000000000000000000000000000000000001":31:0
+
+ECP write key: secp256r1, mostly-0 key, output_size=1 (fits)
+depends_on:MBEDTLS_ECP_DP_SECP256R1_ENABLED
+ecp_write_key:MBEDTLS_ECP_DP_SECP256R1:"0000000000000000000000000000000000000000000000000000000000000001":1:0
+
+ECP write key: secp384r1, nominal
+depends_on:MBEDTLS_ECP_DP_SECP384R1_ENABLED
+ecp_write_key:MBEDTLS_ECP_DP_SECP384R1:"d27335ea71664af244dd14e9fd1260715dfd8a7965571c48d709ee7a7962a156d706a90cbcb5df2986f05feadb9376f1":48:0
+
+ECP write key: secp384r1, output longer by 1
+depends_on:MBEDTLS_ECP_DP_SECP384R1_ENABLED
+ecp_write_key:MBEDTLS_ECP_DP_SECP384R1:"d27335ea71664af244dd14e9fd1260715dfd8a7965571c48d709ee7a7962a156d706a90cbcb5df2986f05feadb9376f1":49:0
+
+ECP write key: secp384r1, output longer by 48
+depends_on:MBEDTLS_ECP_DP_SECP384R1_ENABLED
+ecp_write_key:MBEDTLS_ECP_DP_SECP384R1:"d27335ea71664af244dd14e9fd1260715dfd8a7965571c48d709ee7a7962a156d706a90cbcb5df2986f05feadb9376f1":96:0
+
+ECP write key: secp384r1, output longer by 49
+depends_on:MBEDTLS_ECP_DP_SECP384R1_ENABLED
+ecp_write_key:MBEDTLS_ECP_DP_SECP384R1:"d27335ea71664af244dd14e9fd1260715dfd8a7965571c48d709ee7a7962a156d706a90cbcb5df2986f05feadb9376f1":97:0
+
+ECP write key: secp384r1, output short by 1
+depends_on:MBEDTLS_ECP_DP_SECP384R1_ENABLED
+ecp_write_key:MBEDTLS_ECP_DP_SECP384R1:"d27335ea71664af244dd14e9fd1260715dfd8a7965571c48d709ee7a7962a156d706a90cbcb5df2986f05feadb9376f1":47:MBEDTLS_ERR_MPI_BUFFER_TOO_SMALL
+
+ECP write key: secp384r1, output_size=1
+depends_on:MBEDTLS_ECP_DP_SECP384R1_ENABLED
+ecp_write_key:MBEDTLS_ECP_DP_SECP384R1:"d27335ea71664af244dd14e9fd1260715dfd8a7965571c48d709ee7a7962a156d706a90cbcb5df2986f05feadb9376f1":1:MBEDTLS_ERR_MPI_BUFFER_TOO_SMALL
+
+ECP write key: secp384r1, output_size=0
+depends_on:MBEDTLS_ECP_DP_SECP384R1_ENABLED
+ecp_write_key:MBEDTLS_ECP_DP_SECP384R1:"d27335ea71664af244dd14e9fd1260715dfd8a7965571c48d709ee7a7962a156d706a90cbcb5df2986f05feadb9376f1":0:MBEDTLS_ERR_MPI_BUFFER_TOO_SMALL
+
+ECP write key: Curve25519, nominal
+depends_on:MBEDTLS_ECP_DP_CURVE25519_ENABLED
+ecp_write_key:MBEDTLS_ECP_DP_CURVE25519:"a046e36bf0527c9d3b16154b82465edd62144c0ac1fc5a18506a2244ba449a44":32:0
+
+ECP write key: Curve25519, output longer by 1
+depends_on:MBEDTLS_ECP_DP_CURVE25519_ENABLED
+ecp_write_key:MBEDTLS_ECP_DP_CURVE25519:"a046e36bf0527c9d3b16154b82465edd62144c0ac1fc5a18506a2244ba449a44":33:0
+
+ECP write key: Curve25519, output longer by 32
+depends_on:MBEDTLS_ECP_DP_CURVE25519_ENABLED
+ecp_write_key:MBEDTLS_ECP_DP_CURVE25519:"a046e36bf0527c9d3b16154b82465edd62144c0ac1fc5a18506a2244ba449a44":64:0
+
+ECP write key: Curve25519, output longer by 33
+depends_on:MBEDTLS_ECP_DP_CURVE25519_ENABLED
+ecp_write_key:MBEDTLS_ECP_DP_CURVE25519:"a046e36bf0527c9d3b16154b82465edd62144c0ac1fc5a18506a2244ba449a44":65:0
+
+ECP write key: Curve25519, output short by 1
+depends_on:MBEDTLS_ECP_DP_CURVE25519_ENABLED
+ecp_write_key:MBEDTLS_ECP_DP_CURVE25519:"a046e36bf0527c9d3b16154b82465edd62144c0ac1fc5a18506a2244ba449a44":31:MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL
+
+ECP write key: Curve25519, output_size=1
+depends_on:MBEDTLS_ECP_DP_CURVE25519_ENABLED
+ecp_write_key:MBEDTLS_ECP_DP_CURVE25519:"a046e36bf0527c9d3b16154b82465edd62144c0ac1fc5a18506a2244ba449a44":1:MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL
+
+ECP write key: Curve25519, output_size=0
+depends_on:MBEDTLS_ECP_DP_CURVE25519_ENABLED
+ecp_write_key:MBEDTLS_ECP_DP_CURVE25519:"a046e36bf0527c9d3b16154b82465edd62144c0ac1fc5a18506a2244ba449a44":0:MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL
+
+ECP write key: Curve25519, mostly-0 key, output_size=32
+depends_on:MBEDTLS_ECP_DP_CURVE25519_ENABLED
+ecp_write_key:MBEDTLS_ECP_DP_CURVE25519:"0000000000000000000000000000000000000000000000000000000000000040":32:0
+
+ECP write key: Curve25519, mostly-0 key, output_size=31
+depends_on:MBEDTLS_ECP_DP_CURVE25519_ENABLED
+ecp_write_key:MBEDTLS_ECP_DP_CURVE25519:"0000000000000000000000000000000000000000000000000000000000000040":31:MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL
+
 ECP mod p192 small (more than 192 bits, less limbs than 2 * 192 bits)
 depends_on:MBEDTLS_ECP_DP_SECP192R1_ENABLED
 ecp_fast_mod:MBEDTLS_ECP_DP_SECP192R1:"0100000000000103010000000000010201000000000001010100000000000100"
diff --git a/tests/suites/test_suite_ecp.function b/tests/suites/test_suite_ecp.function
index 443bc08..da13720 100644
--- a/tests/suites/test_suite_ecp.function
+++ b/tests/suites/test_suite_ecp.function
@@ -1383,6 +1383,66 @@
 }
 /* END_CASE */
 
+/* BEGIN_CASE */
+void ecp_write_key(int grp_id, data_t *in_key,
+                   int exported_size, int expected_ret)
+{
+    mbedtls_ecp_keypair key;
+    mbedtls_ecp_keypair_init(&key);
+    unsigned char *exported = NULL;
+
+    TEST_EQUAL(mbedtls_ecp_read_key(grp_id, &key, in_key->x, in_key->len), 0);
+
+    TEST_CALLOC(exported, exported_size);
+    TEST_EQUAL(mbedtls_ecp_write_key(&key, exported, exported_size),
+               expected_ret);
+
+    if (expected_ret == 0) {
+        size_t length = (key.grp.nbits + 7) / 8;
+        const unsigned char *key_start = NULL;
+        const unsigned char *zeros_start = NULL;
+        switch (mbedtls_ecp_get_type(&key.grp)) {
+            case MBEDTLS_ECP_TYPE_SHORT_WEIERSTRASS:
+                if ((size_t) exported_size < length) {
+                    length = exported_size;
+                }
+                key_start = exported + exported_size - length;
+                zeros_start = exported;
+                break;
+            case MBEDTLS_ECP_TYPE_MONTGOMERY:
+                TEST_LE_U(length, exported_size);
+                key_start = exported;
+                zeros_start = exported + length;
+                break;
+            default:
+                TEST_FAIL("Unknown ECP curve type");
+                break;
+        }
+
+        if (length < in_key->len) {
+            /* Shorter output (only possible with Weierstrass keys) */
+            for (size_t i = 0; i < in_key->len - length; i++) {
+                mbedtls_test_set_step(i);
+                TEST_EQUAL(in_key->x[i], 0);
+            }
+            TEST_MEMORY_COMPARE(in_key->x + in_key->len - length, length,
+                                key_start, length);
+        } else {
+            TEST_MEMORY_COMPARE(in_key->x, in_key->len,
+                                key_start, length);
+            for (size_t i = 0; i < exported_size - length; i++) {
+                mbedtls_test_set_step(i);
+                TEST_EQUAL(zeros_start[i], 0);
+            }
+        }
+    }
+
+exit:
+    mbedtls_ecp_keypair_free(&key);
+    mbedtls_free(exported);
+}
+/* END_CASE */
+
 /* BEGIN_CASE depends_on:HAVE_FIX_NEGATIVE */
 void fix_negative(data_t *N_bin, int c, int bits)
 {
diff --git a/tests/suites/test_suite_pk.function b/tests/suites/test_suite_pk.function
index 2111926..9d3570e 100644
--- a/tests/suites/test_suite_pk.function
+++ b/tests/suites/test_suite_pk.function
@@ -18,6 +18,13 @@
 #define RSA_KEY_SIZE 512
 #define RSA_KEY_LEN   64
 
+#if defined(MBEDTLS_RSA_C) ||                                           \
+    defined(MBEDTLS_PK_RSA_ALT_SUPPORT) ||                              \
+    defined(MBEDTLS_ECDSA_C) ||                                         \
+    defined(MBEDTLS_USE_PSA_CRYPTO)
+#define PK_CAN_SIGN_SOME
+#endif
+
 /** Generate a key of the desired type.
  *
  * \param pk        The PK object to fill. It must have been initialized
@@ -894,7 +901,7 @@
 }
 /* END_CASE */
 
-/* BEGIN_CASE depends_on:MBEDTLS_SHA256_C */
+/* BEGIN_CASE depends_on:MBEDTLS_SHA256_C:PK_CAN_SIGN_SOME */
 void pk_sign_verify(int type, int parameter, int sign_ret, int verify_ret)
 {
     mbedtls_pk_context pk;