mbedtls with hardware SHA engine

[yoursunny]

Hardware:

Board: Heltec WiFi Kit 32
Core Installation/update date: 70d0d46
IDE name: Arduino 1.8.5
Flash Frequency: 80Mhz
Upload Speed: 115200

Description:

CONFIG_MBEDTLS_HARDWARE_SHA option is disabled.
As a result, SHA256 computation is slow.

Sketch:

#include <mbedtls/sha256.h>

void setup() {
  Serial.begin(115200);
  Serial.println();
}

void loop() {
  unsigned long t0 = micros();
  mbedtls_sha256_context ctx;
  mbedtls_sha256_init(&ctx);
  for (int i = 0; i < 16777216; ++i) {
    Serial.printf("mode=%d\n", ctx.mode);
    mbedtls_sha256_update(&ctx, reinterpret_cast<const uint8_t*>("abcdefghbcdefghicdefghijdefghijkefghijklfghijklmghijklmnhijklmno"), 64);
  }
  uint8_t digest[32];
  mbedtls_sha256_finish(&ctx, digest);
  mbedtls_sha256_free(&ctx);
  unsigned long t1 = micros();

  for (int i = 0; i < sizeof(digest); ++i) {
    Serial.printf("%02x", digest[i]);
  }
  Serial.println();
  Serial.printf("duration=%lu\n", t1 - t0);
}

Debug Messages:

In "alt" version of mbedtls_sha256_context, there is a mode member that indicates whether hardware or software SHA engine is selected.
The sketch does not compile because the mbedtls_sha256_context only supports software implementation.

sha256-mbedtls:13: error: 'struct mbedtls_sha256_context' has no member named 'mode'

     Serial.printf("mode=%d\n", ctx.mode);

[copercini]

It has disabled due an old bug in hardware acceleration that crash mbedltls sometimes (espressif/esp-idf#630)
It's fixed on IDF now and just waiting for the update for Arduino here: #964

[yoursunny]

Core Installation/update date: 172802b
Now that #964 is closed, but CONFIG_MBEDTLS_HARDWARE_SHA stays disabled.
Can this be enabled?

I tried modifying tools/sdk/sdkconfig but it does not seem to be effective. I don't know how to regenerate binaries in there.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[yoursunny]

This issue should remain open. Enabling hardware SHA engine is a useful performance improvement.

[stale]

[STALE_SET] This issue has been automatically marked as stale because it has not had recent activity. It will be closed in 14 days if no further activity occurs. Thank you for your contributions.

[yoursunny]

This issue should remain open. Enabling hardware SHA engine is a useful performance improvement.

[stale]

[STALE_CLR] This issue has been removed from the stale queue. Please ensure activity to keep it openin the future.

[stale]

[STALE_SET] This issue has been automatically marked as stale because it has not had recent activity. It will be closed in 14 days if no further activity occurs. Thank you for your contributions.

[yoursunny]

This issue should remain open. Enabling hardware SHA engine is a useful performance improvement.