Zcash zk-SNARK public parameters for 1.0 "Sprout".
Created in the ceremony this weekend! 🎉
We're writing a blog post about this, I'm going to publish the code shortly too.
Closes#1553
This will retry upon refused connections and similar errors, wait 1 second
before the next retry, time out after 10 seconds if no data is received or
the connection times out, plus try an infinite number of times.
Per NCC-2016-017, wget was run with --no-check-certificate,
which means that the connection can be man-in-the-middled,
even if we are verifying the integrity of the params later via hash sums.
The rationale cited in the Bash comments does not stand up to scrutiny.
There's really no persuasive reason not to verify certificates.
Fixes#1346.
Two instances of the fetch-params.sh script running at once will
result in corruption of the proving key and an error when the
hashes are computed. This implements a lock to stop such a
scenario from occurring.
We also terminate and don't create the symlinks if the downloaded
parameters fail the checksum command.