schnorrkel (with no_std support) doesn't work with sgx

[brenzi]

I'm currently trying to use

https://github.com/w3f/schnorrkel

within an sgx enclave here:

https://github.com/scs/substraTEE-worker/blob/37c76121c4bbf4e3eee210b29e7c4f2d5de1ada9/enclave/src/lib.rs#L35

The library supports #[no_std]. As @dingelish wrote here, this crate should be automatically supported, right?

However, if I add

extern crate schnorrkel;
use schnorrkel::keys::MiniSecretKey;

I get the usual std collision:

error: duplicate lang item in crate `std`: `f32_runtime`.
  |
  = note: first defined in crate `sgx_tstd`.

error: duplicate lang item in crate `std`: `f64_runtime`.
  |
  = note: first defined in crate `sgx_tstd`.

error: duplicate lang item in crate `std`: `panic_impl`.
  |
  = note: first defined in crate `sgx_tstd`.

error: duplicate lang item in crate `std`: `oom`.
  |
  = note: first defined in crate `sgx_trts`.

error: aborting due to 4 previous errors

error: Could not compile `SealedKeyEnclave`.

To learn more, run the command again with --verbose.

Any help is appreciated

[elichai]

By default this library uses std
Try importing it with default-features=false
And features=["alloc"] or alloc and nightly together

[brenzi]

ok, I see.

But now I get:

   Compiling schnorrkel v0.1.1
error[E0433]: failed to resolve: maybe a missing `extern crate std;`?
  --> /home/abrenzikofer/.cargo/registry/src/github.com-1ecc6299db9ec823/schnorrkel-0.1.1/src/context.rs:13:5
   |
13 | use std::cell::RefCell;
   |     ^^^ maybe a missing `extern crate std;`?

error[E0433]: failed to resolve: unresolved import
   --> /home/abrenzikofer/.cargo/registry/src/github.com-1ecc6299db9ec823/schnorrkel-0.1.1/src/sign.rs:245:9
    |
245 |     use alloc::vec::Vec;
    |         ^^^^^
    |         |
    |         unresolved import
    |         help: a similar path exists: `core::alloc`

It seems I'll have to fork schnorrkel and put

#[macro_use]
extern crate sgx_tstd as std;
use std::prelude::v1::*;

Or do you have other ideas?

[elichai]

it looks like they messed up the no-std feature, they don't import alloc if you use the alloc feature, and they still use std sometimes even when they could use core.
open an issue there telling them that it's broken.
but in general be really cautious about using random cryptography libraries.

[brenzi]

problem needs to be solved upstream