diff --git a/tests/configs/user-config-for-test.h b/tests/configs/user-config-for-test.h
index 444a4bf..8c2680d 100644
--- a/tests/configs/user-config-for-test.h
+++ b/tests/configs/user-config-for-test.h
@@ -55,3 +55,23 @@
 #define MBEDTLS_PSA_ACCEL_ALG_HMAC
 
 #endif  /* PSA_CRYPTO_DRIVER_TEST_ALL */
+
+
+
+#if defined(MBEDTLS_PSA_INJECT_ENTROPY)
+/* The #MBEDTLS_PSA_INJECT_ENTROPY feature requires two extra platform
+ * functions, which must be configured as #MBEDTLS_PLATFORM_NV_SEED_READ_MACRO
+ * and #MBEDTLS_PLATFORM_NV_SEED_WRITE_MACRO. The job of these functions
+ * is to read and write from the entropy seed file, which is located
+ * in the PSA ITS file whose uid is #PSA_CRYPTO_ITS_RANDOM_SEED_UID.
+ * (These could have been provided as library functions, but for historical
+ * reasons, they weren't, and so each integrator has to provide a copy
+ * of these functions.)
+ *
+ * Provide implementations of these functions for testing. */
+#include <stddef.h>
+int mbedtls_test_inject_entropy_seed_read(unsigned char *buf, size_t len);
+int mbedtls_test_inject_entropy_seed_write(unsigned char *buf, size_t len);
+#define MBEDTLS_PLATFORM_NV_SEED_READ_MACRO mbedtls_test_inject_entropy_seed_read
+#define MBEDTLS_PLATFORM_NV_SEED_WRITE_MACRO mbedtls_test_inject_entropy_seed_write
+#endif /* MBEDTLS_PSA_INJECT_ENTROPY */