Acknowledgements
Thanks to everyone who has contributed to this design with feedback and discussion.
Thanks go to arma, ioerror, kernelcorn, nickm, s7r, Sebastian, teor, weasel and everyone else!
References:
[RANDOM-REFS]:
http://projectbullrun.org/dual-ec/ext-rand.html
https://lists.torproject.org/pipermail/tor-dev/2015-November/009954.html
[RNGMESSAGING]:
https://moderncrypto.org/mail-archive/messaging/2015/002032.html
[HOPPER]:
https://lists.torproject.org/pipermail/tor-dev/2014-January/006053.html
[UNICORN]:
https://eprint.iacr.org/2015/366.pdf
[VDFS]:
https://eprint.iacr.org/2018/601.pdf