rust: Update ed25519-dalek and associated dependencies

[peterjgilbert]

1.0.0-pre.3 needs rand 0.7

[codecov]

Codecov Report

Merging #2678 into master will increase coverage by 0.03%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #2678      +/-   ##
==========================================
+ Coverage   63.09%   63.12%   +0.03%     
==========================================
  Files         376      376              
  Lines       35319    35319              
==========================================
+ Hits        22283    22294      +11     
  Misses      10230    10230              
+ Partials     2806     2795      -11     

Impacted Files	Coverage Δ
go/worker/common/host/interface.go	38.46% <0.00%> (-15.39%)	⬇️
go/consensus/tendermint/api/api.go	73.58% <0.00%> (-15.10%)	⬇️
go/worker/compute/txnscheduler/committee/node.go	60.18% <0.00%> (-4.33%)	⬇️
go/worker/common/p2p/p2p.go	67.56% <0.00%> (-2.71%)	⬇️
go/consensus/tendermint/roothash/roothash.go	68.91% <0.00%> (-2.63%)	⬇️
...o/consensus/tendermint/apps/scheduler/scheduler.go	71.70% <0.00%> (-1.38%)	⬇️
go/common/grpc/grpc.go	77.59% <0.00%> (-1.25%)	⬇️
go/runtime/client/client.go	66.28% <0.00%> (-0.77%)	⬇️
go/roothash/tests/tester.go	95.54% <0.00%> (-0.64%)	⬇️
go/storage/client/client.go	78.15% <0.00%> (+0.84%)	⬆️
... and 14 more

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update afc5248...2862c9b. Read the comment docs.

[kostko]

What exactly is the problem with the rand crates? Is it a problem with SGX builds or in general?

[peterjgilbert]

Not specific to SGX builds. This is the error I get when compiling oasis-core-runtime outside of oasis-core:

...
   Compiling ed25519-dalek v1.0.0-pre.3
   Compiling oasis-core-runtime v0.3.0-alpha (https://github.com/oasislabs/oasis-core#a7d41660)
error[E0277]: the trait bound `rand_os::OsRng: rand_core::CryptoRng` is not satisfied
  --> /root/.cargo/git/checkouts/oasis-core-d1e566606c486e34/a7d4166/runtime/src/common/crypto/signature.rs:41:20
   |
41 |         PrivateKey(ed25519_dalek::Keypair::generate(&mut rng))
   |                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `rand_core::CryptoRng` is not implemented for `rand_os::OsRng`
   |
   = note: required by `ed25519_dalek::ed25519::Keypair::generate`

error[E0277]: the trait bound `rand_os::OsRng: rand_core::RngCore` is not satisfied
  --> /root/.cargo/git/checkouts/oasis-core-d1e566606c486e34/a7d4166/runtime/src/common/crypto/signature.rs:41:20
   |
41 |         PrivateKey(ed25519_dalek::Keypair::generate(&mut rng))
   |                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `rand_core::RngCore` is not implemented for `rand_os::OsRng`
   |
   = note: required by `ed25519_dalek::ed25519::Keypair::generate`

error: aborting due to 2 previous errors

For more information about this error, try `rustc --explain E0277`.
error: Could not compile `oasis-core-runtime`.

[kostko]

If it is just that, it looks like something that would be simple to fix?