Wasm support

[Tartopoms]

Cannot compile cryptoki-sys to wasm target

Related to: Cannot compile dependency: could not find Library in libloading #1641

When I build, watch & serve a Rust WASM app with cryptoki, its dependency cryptoki-sys raise a compilation error.

The error is:

# cargo check --target wasm32-unknown-unknown
    Checking ...
    Checking cryptoki-sys v0.1.7 (registry `custom-regsitry`)
error[E0433]: failed to resolve: could not find `Library` in `libloading`
    --> /root/.cargo/registry/src/custom-regsitry-url/cryptoki-sys-0.1.7/src/bindings/generic.rs:2164:37
     |
2164 |         let library = ::libloading::Library::new(path)?;
     |                                     ^^^^^^^ could not find `Library` in `libloading`

error[E0412]: cannot find type `Library` in crate `libloading`
    --> /root/.cargo/registry/src/custom-regsitry-url/cryptoki-sys-0.1.7/src/bindings/generic.rs:1634:30
     |
1634 |     __library: ::libloading::Library,
     |                              ^^^^^^^ not found in `libloading`

error[E0412]: cannot find type `Library` in crate `libloading`
    --> /root/.cargo/registry/src/custom-regsitry-url/cryptoki-sys-0.1.7/src/bindings/generic.rs:2169:31
     |
2169 |         L: Into<::libloading::Library>,
     |                               ^^^^^^^ not found in `libloading`

Some errors have detailed explanations: E0412, E0433.
For more information about an error, try `rustc --explain E0412`.
error: could not compile `cryptoki-sys` (lib) due to 3 previous errors

Steps To Reproduce

• Make sure the wasm32-unknown-unknown target for rust is installed
  • rustup target add wasm32-unknown-unknown
    • (if you are using a custom Rust toolchain, add the wasm32 component into your rust/toolchains/$custom-toolchain/components/ folder
• Install the dioxus command line allowing you to compile your rust app to wasm target
  • cargo install dioxus-cli
  • dx --help
• Create a rust application using the default dioxus template: dx create, and select the following options:
  • If you are working in an offline workspace:
    • download/unzip the dioxus-template
    • run instead: dx create --template dioxus-template-main
  • If $USER not found -> export USER=any, the value do not matter

# dx create --template dioxus-template-main
[WARN] You appear to be creating a Dioxus project from scratch; we will use the default config
[WARN] Favorite `dioxus-template-main` not found in config, using it as a local path: dioxus-template-main
...
✔  What platform are you targeting? · web
✔  Should the application use the dioxus router? · true
✔  How do you want to create CSS? · Vanilla
...

Expected behavior

Being able to compile after running dx serve:

Project Reloaded: Changed 1 files. [xx:xx:xx]

        > Local : http://localhost:8080/
        > Network : http://<IP>:8080/
        > HTTPS : Disabled

        > Profile : Debug
        > Hot Reload : Normal
        > Index Template : Default
        > URL Rewrite [index_on_404] : False

        > Build Time Use : 1190 millis

[INFO] A perfect compilation!

Environment:

I'm working on a Docker Container, offline, with a custom Rust toolchain and a custom registry. I've been working with them for 3 months and have never had a problem so far, so I want to remove these two from the possible error case.

With my toolchain and registry: I have two full Rust apps working. One with an Axum server and Dioxus client, communicating with REST and WebSockets. Another with cryptoki (RSA PKCS#11), without any issue so far.

• Dioxus version: v0.4.0
• Dioxus cli version: v0.4.1
• Cryptoki version: v0.6.1
• Rust version: 1.70.0, stable
• OS info: Docker container: Debian GNU/Linux 11 (bullseye)

Questionnaire

• I'm interested in fixing this myself but don't know where to start

[wiktor-k]

Just out of curiosity what would be the use case? Cryptoki frequently needs PKCS11 driver anyway and you'd have to be able to access the device somehow (eg. via pcsclite).

[Tartopoms]

I'm working on a light web client to interact with an HSM and a database.

[hug-dev]

There is something related in libloading: https://github.com/nagisa/rust_libloading/blob/5102b4a3669c63968eda31b072516ef6ae891ee4/src/changelog.rs#L82
Has libloading itself support for WASM?

[wiktor-k]

Has libloading itself support for WASM?

Alternatively we could hide libloading behind a default enabled feature 🤔

[hug-dev]

If an implementation of PKCS11 as a static library is available, one could investigate linking with it at build time and then everything could be packaged inside the wasm binary, without needing libloading.