Improved Arduino Support: ESP32, Due

[gojimmypi]

Description

This PR improves support for the Arduino platform.

I'll be testing other Arduino boards, but I've added the help wanted label to invite others to test these changes with various other devices.

Of particular interest, gated sections added to:

• src/internal.c (only a placeholder reminder / not part of "else" gating)
• wolfcrypt/src/random.c (more board-specific implementation will be needed here)
• wolfssl/wolfcrypt/settings.h (only AVR, ARM, and Espressif at this time)
• wolfssl/wolfcrypt/tfm.h (just a spelling correction)
• wolfssl/wolfcrypt/wc_port.h (only basic Arduino support, likely needs work for other boards)
• wolfssl/ssl.h (only a placeholder reminder & adjacent cleanup)
• wolfssl/test.h (only a placeholder reminder; test.h not yet working in Arduino)
• wolfssl/wolfio.h (only Espressif at this time)

Fixes zd# may help with 17001, although more ESP8266 work is known to be needed.

See also #6360 and wolfSSL/Arduino-wolfSSL#1

Testing

How did you test?

Primarily tested in the Arduino environment, as well as the usual:

./configure --enable-all
make clean
make && make test

Checklist

• added tests
• updated/added doxygen
• updated appropriate READMEs
• Updated manual and documentation

[dgarske]

What hardware have you tested with?

[dgarske]

Why is this commented out and still here?

[gojimmypi]

oh, that was an oversight. good catch, deleted.

[dgarske]

What is WOLFSSL_MEMORY_STORAGE? Please document

[gojimmypi]

WOLFSSL_MEMORY_STORAGE is an experimental macro for the Arduino-specific F(string_literal) macro class to help improve memory storage.

I'll review and either add more detail or remove for now.

*edit: I've removed the WOLFSSL_MEMORY_STORAGE macro for now.

[dgarske]

Why need this at all? Seems like requiring WOLFSSL_USER_IO is the better option. Then you can remove this.

[gojimmypi]

oh, nice. excellent suggestion, thank you. changed.

[dgarske]

Would prefer a link to the ChangeLog.md and not duplicating.

[gojimmypi]

This is different from the change log.

My intention for the PREPENDED_README.md is to add some prepended text to the beginning of the library README.md published in the Official wolfSSL Arduino Library to indicate the Arduino-specific nature.

This prepended text might have Arduino-specific release information, outside of the normal wolfSSL versions, that are needed to be tagged as noted in the Arduino Library Specifications and noted in the requirements:

The library repository must have a Git tag (or release) and must have been compliant with all the above requirements at the time of that tag.

There is however, an argument that the PREPENDED_README.md file is only a temporary file for the published wolfSSL Arduino README.md and could be excluded here?

edit: I've removed the programmatically generated PREPENDED_README.md and added the name to .gitignore.

[gojimmypi]

What hardware have you tested with?

So far I've successfully tested with two different ESP32 devices and an ARM-based Arduino Due.

I have an Arduino Uno rev 3 with an Ethernet Shield. I gave up trying to fit TLS into the 8KB RAM, but we might be able to do other things.

I tried a Arduino Mega & gave up for the same small memory reason. I've ben focused on the TLS client & server examples.

I have a Arduino Uno R4 WiFi on my workbench that is known to not work yet. (Renesas RA4M1 + Espressif ESP32-S3)

I have a variety of other non-Arduino devices that could be tested. There's quite a list of Arduino and compatible systems on wikipedia.

The Due is fairly easy to get going. Each of the ESP32 dev boards were different, and neither worked out of the box. Both of the ESP32 devices needed manual settings adjustment. For instance:

Board 1 ESP32 Dev Module	Board 2 DOIT ESP32 Devkit V1

*edit: just to clarify: I've tested with some other boards, but the source for those updated examples is still WIP. I'll be creating a separate PR for the Arduino Client and Server examples in the coming weeks,

[dgarske]

Retest this please

[gojimmypi]

retest this please

[gojimmypi]

@dgarske if you could kindly re-approve; looks like your approval was dismissed when I pushed the additional commit to fix the build complaint about C++ style comments. Thanks @bandi13 for pointing it out.

[dgarske]

Looks good. Lets find an engineer to also try this out.

[night1rider]

I used our internal testing for the Intel Galileo, and was able to produce the same results as the old version ./wolfssl-arduino.sh.
This is our simple client server hello test adapted for the Galileo.

This test does the following:

• Pulls the requested repo for wolfssl
• Navigates to IDE/ARDUINO and runs ./wolfssl-arduino.sh INSTALL
• pull downs the Arduino toolchain/ide and places the generated IDE/ARDUINO/wolfSSL library folder into the appropriate directory for the toolchain/ide and updates user_settings.h
• compiles the wolfssl client example in IDE/ARDUINO/sketches/wolfssl_client/wolfssl_client.ino
• programs the Galileo and starts a server for the client to connect to to preform a client server hello

I made some suggestions for the README directly to Jim, these suggestions where due to the confusion of using option 1 for step 1. This has been clarified as of posting this comment and the README updated

I have not tested with a ESP32/Arduino DUE since I lack the hardware to test the functionality of that portion of the PR.

[gojimmypi]

Jenkins retest this please.