Add a test for external alternate timing implementation
Copy the original implementation
Signed-off-by: Andrzej Kurek <andrzej.kurek@arm.com>
diff --git a/tests/src/external_timing/timing_alt.h b/tests/src/external_timing/timing_alt.h
new file mode 100644
index 0000000..204dbe8
--- /dev/null
+++ b/tests/src/external_timing/timing_alt.h
@@ -0,0 +1,130 @@
+/*
+ * Copy of the internal MbedTLS timing implementation, to be used in tests.
+ */
+/*
+ * Copyright The Mbed TLS Contributors
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef EXTERNAL_TIMING_FOR_TEST_H
+#define EXTERNAL_TIMING_FOR_TEST_H
+
+#if !defined(MBEDTLS_CONFIG_FILE)
+#include "mbedtls/config.h"
+#else
+#include MBEDTLS_CONFIG_FILE
+#endif
+
+#include <stdint.h>
+
+/**
+ * \brief timer structure
+ */
+struct mbedtls_timing_hr_time {
+ unsigned char opaque[32];
+};
+
+/**
+ * \brief Context for mbedtls_timing_set/get_delay()
+ */
+typedef struct mbedtls_timing_delay_context {
+ struct mbedtls_timing_hr_time timer;
+ uint32_t int_ms;
+ uint32_t fin_ms;
+} mbedtls_timing_delay_context;
+
+#else /* MBEDTLS_TIMING_ALT */
+#include "timing_alt.h"
+#endif /* MBEDTLS_TIMING_ALT */
+
+extern volatile int mbedtls_timing_alarmed;
+
+/**
+ * \brief Return the CPU cycle counter value
+ *
+ * \warning This is only a best effort! Do not rely on this!
+ * In particular, it is known to be unreliable on virtual
+ * machines.
+ *
+ * \note This value starts at an unspecified origin and
+ * may wrap around.
+ */
+unsigned long mbedtls_timing_hardclock(void);
+
+/**
+ * \brief Return the elapsed time in milliseconds
+ *
+ * \param val points to a timer structure
+ * \param reset If 0, query the elapsed time. Otherwise (re)start the timer.
+ *
+ * \return Elapsed time since the previous reset in ms. When
+ * restarting, this is always 0.
+ *
+ * \note To initialize a timer, call this function with reset=1.
+ *
+ * Determining the elapsed time and resetting the timer is not
+ * atomic on all platforms, so after the sequence
+ * `{ get_timer(1); ...; time1 = get_timer(1); ...; time2 =
+ * get_timer(0) }` the value time1+time2 is only approximately
+ * the delay since the first reset.
+ */
+unsigned long mbedtls_timing_get_timer(struct mbedtls_timing_hr_time *val, int reset);
+
+/**
+ * \brief Setup an alarm clock
+ *
+ * \param seconds delay before the "mbedtls_timing_alarmed" flag is set
+ * (must be >=0)
+ *
+ * \warning Only one alarm at a time is supported. In a threaded
+ * context, this means one for the whole process, not one per
+ * thread.
+ */
+void mbedtls_set_alarm(int seconds);
+
+/**
+ * \brief Set a pair of delays to watch
+ * (See \c mbedtls_timing_get_delay().)
+ *
+ * \param data Pointer to timing data.
+ * Must point to a valid \c mbedtls_timing_delay_context struct.
+ * \param int_ms First (intermediate) delay in milliseconds.
+ * The effect if int_ms > fin_ms is unspecified.
+ * \param fin_ms Second (final) delay in milliseconds.
+ * Pass 0 to cancel the current delay.
+ *
+ * \note To set a single delay, either use \c mbedtls_timing_set_timer
+ * directly or use this function with int_ms == fin_ms.
+ */
+void mbedtls_timing_set_delay(void *data, uint32_t int_ms, uint32_t fin_ms);
+
+/**
+ * \brief Get the status of delays
+ * (Memory helper: number of delays passed.)
+ *
+ * \param data Pointer to timing data
+ * Must point to a valid \c mbedtls_timing_delay_context struct.
+ *
+ * \return -1 if cancelled (fin_ms = 0),
+ * 0 if none of the delays are passed,
+ * 1 if only the intermediate delay is passed,
+ * 2 if the final delay is passed.
+ */
+int mbedtls_timing_get_delay(void *data);
+
+#ifdef __cplusplus
+}
+
+#endif /* FAKE_EXTERNAL_RNG_FOR_TEST_H */