Doing a quick look through the library repository, I spotted another more scary function. It doesn't appear (at a quick glance) to be used anywhere, but still..

Doing a quick look through the library repository, I spotted another more scary function. It doesn't appear (at a quick glance) to be used anywhere, but still... https://github.com/trustcrypto/libraries/blob/master/randombytes/randombytes.c https://github.com/trustcrypto/libraries/blob/master/randomb... For anyone wanting to try this out (it will compile with plain GCC if you add): #include <stdlib.h> #include <stdio.h> to the start of the file, and declare a main function: void main() { unsigned char* buffer; buffer = malloc(32 * sizeof(char)); randombytes(buffer, 32); for (int i=0; i < 32; i++) { printf("%02x", buffer[i]); } printf("\n"); free(buffer); } And you'll (of course) get some rather deterministic output. As I say though, doesn't look to be used (that I could see), but strange to have something like this there. RE the RNG implementation, looks to be at https://github.com/trustcrypto/libraries/blob/master/Crypto/RNG.cpp https://github.com/trustcrypto/libraries/blob/master/Crypto/..., and looks to have some support for hardware RNGs on certain boards, but not others. Does sound like there's no hardware protection involved.