Re-implement PKI from #1509 (#4379)

* Re-implement PKI from #1509
co-authored-by: edinnen <ethanjdinnen@protonmail.com>

* Set the key lengnth to actually make PKI work.

* Remove unused variable and initialize keys to null

* move printBytes() to meshUtils

* Don't reset PKI key son reboot unless needed.

* Remove double encryption for PKI messages

* Cleanup encrypt logic

* Add the MESHTASTIC_EXCLUDE_PKI option, and set it for minimal builds. Required for STM32 targets for now.

* Use SHA-256 for PKI key hashing, and add MESHTASTIC_EXCLUDE_PKI_KEYGEN for STM32

* Fix a crash when node is null

* Don't send PKI encrypted packets while licensed

* use chIndex 8 for PKI

* Don't be so clever, that you corrupt incoming packets

* Pass on channel 8 for now

* Typo

* Lock keys once non-zero

* We in fact need 2 scratch buffers, to store the encrypted bytes, unencrypted bytes, and decoded protobuf.

* Lighter approach to retaining known key

* Attach the public key to PKI decrypted packets in device memory

* Turn PKI back off for STM32 :(

* Don't just memcp over a protobuf

* Don't PKI encrypt nodeinfo packets

* Add a bit more memory logging around nodeDB

* Use the proper macro to refer to NODENUM_BROADCAST

* Typo fix

* Don't PKI encrypt ROUTING (naks and acks)

* Adds SecurityConfig protobuf

* Add admin messages over PKI

* Disable PKI for the WIO-e5

* Add MINIMUM_SAFE_FREE_HEAP macro and set to safe 1.5k

* Add missed "has_security"

* Add the admin_channel_enabled option

* STM32 again

* add missed configuration.h at the top of files

* Add EXCLUDE_TZ and RTC

* Enable PKI build on STM32 once again

* Attempt 1 at moving PKI to aes-ccm

* Fix buffers for encrypt/decrypt

* Eliminate unused aes variable

* Add debugging lines

* Set hash to 0 for PKI

* Fix debug lines so they don't print pointers.

* logic fix and more debug

* Rather important typo

* Check for short packets before attempting decrypt

* Don't forget to give cryptoEngine the keys!

* Use the right scratch buffer

* Cleanup

* moar cleanups

* Minor hardening

* Remove some in-progress stuff

* Turn PKI back off on STM32

* Return false

* 2.5 protos

* Sync up protos

* Add initial cryptography test vector tests

* re-add MINIMUM_SAFE_FREE_HEAP

* Housekeeping and comment fixes

* Add explanatory comment about weak dh25519 keys

---------

Co-authored-by: Ben Meadors <benmmeadors@gmail.com>

arch/esp32/esp32.ini

@@ -48,6 +48,7 @@ lib_deps =
   https://github.com/dbSuS/libpax.git#7bcd3fcab75037505be9b122ab2b24cc5176b587
   https://github.com/lewisxhe/XPowersLib.git#84b7373faea3118b6c37954d52f98b8a337148d6
   https://github.com/meshtastic/ESP32_Codec2.git#633326c78ac251c059ab3a8c430fcdf25b41672f
+  rweather/Crypto@^0.4.0
 
 lib_ignore = 
   segger_rtt

arch/nrf52/nrf52.ini

@@ -20,6 +20,7 @@ build_src_filter =
 
 lib_deps=
   ${arduino_base.lib_deps}
+  rweather/Crypto@^0.4.0
 
 lib_ignore =
   BluetoothOTA