BearSSL EC key/cert generation

[soosp]

Hi,
Is this possible to generate EC key and (self signed) certificate onboard using BearSSL? There is a br_ec_keygen() function in bearssl_ec.h, but need some example how to to use it.

[mcspr]

I see a tool for key generation in the bearssl distribution
https://github.com/earlephilhower/bearssl-esp8266/blob/b024386d461abd1b7b9be3117e2516b7541f1201/tools/skey.c#L433-L460
(also found at $core_installation_dir/tools/sdk/ssl/bearssl/tools/skey.c)

Right now, also needs 'Non-32-Bit Access' (-DNON32XFER_HANDLER) or 3.x.x SDK set in build settings.
https://gist.github.com/mcspr/d9d457b918ef777a0720e5b12fb70036

It is crashing at this point in the code, so I'd assume *order and order[N] should be wrapped with pgm_read_byte
https://github.com/earlephilhower/bearssl-esp8266/blob/b024386d461abd1b7b9be3117e2516b7541f1201/src/ec/ec_keygen.c#L44
Since the crash occurs after it trying to access u8 P256_N[]; that is located in flash (at least, for this variant)
https://github.com/earlephilhower/bearssl-esp8266/blob/c0b69dfb837f0027180c72f13f7c90cfafb83c16/src/ec/ec_secp256r1.c#L27