From c60fae87315e35aace38616b8110649053b576f9 Mon Sep 17 00:00:00 2001
From: gojimmypi <13059545+gojimmypi@users.noreply.github.com>
Date: Thu, 21 Jul 2022 09:08:10 +0200
Subject: [PATCH] wc_Sha256Free checks lockDepth for Espressif RTOS

---
 wolfcrypt/src/sha256.c | 20 +++++++++++++++++++-
 1 file changed, 19 insertions(+), 1 deletion(-)

diff --git a/wolfcrypt/src/sha256.c b/wolfcrypt/src/sha256.c
index 0186588df..dab3c97e3 100644
--- a/wolfcrypt/src/sha256.c
+++ b/wolfcrypt/src/sha256.c
@@ -84,6 +84,7 @@ on the specific device platform.
 #endif
 
 /* determine if we are using Espressif SHA hardware acceleration */
+#undef WOLFSSL_USE_ESP32WROOM32_CRYPT_HASH_HW
 #if defined(WOLFSSL_ESP32WROOM32_CRYPT) && \
     !defined(NO_WOLFSSL_ESP32WROOM32_CRYPT_HASH)
     /* define a single keyword for simplicity & readability
@@ -93,7 +94,7 @@ on the specific device platform.
      */
     #define WOLFSSL_USE_ESP32WROOM32_CRYPT_HASH_HW
 #else
-    #undef USE_ESP32WROOM32_CRYPT_HASH
+    #undef WOLFSSL_USE_ESP32WROOM32_CRYPT_HASH_HW
 #endif
 
 /* fips wrapper calls, user can call direct */
@@ -1734,6 +1735,23 @@ void wc_Sha256Free(wc_Sha256* sha256)
 #ifdef WOLFSSL_IMXRT_DCP
     DCPSha256Free(sha256);
 #endif
+/* Espressif embedded hardware acceleration specific: */
+#if defined(WOLFSSL_USE_ESP32WROOM32_CRYPT_HASH_HW)
+    if (sha256->ctx.lockDepth > 0) {
+        /* probably due to unclean shutdown, error, or other problem.
+         *
+         * if you find yourself here, code needs to be cleaned up to
+         * properly release hardware. this init is only for handling
+         * the unexpected. by the time free is called, the hardware
+         * should have already been released (lockDepth = 0)
+         */
+        InitSha256(sha256); /* unlock mutex, set mode to ESP32_SHA_INIT */
+        ESP_LOGE("sha256", "ERROR: hardware unlock needed in wc_Sha256Free");
+    }
+    else {
+        ESP_LOGV("sha256", "hardware unlock not needed in wc_Sha256Free");
+    }
+#endif
 }
 
 #endif /* !defined(WOLFSSL_HAVE_PSA) || defined(WOLFSSL_PSA_NO_HASH) */