Amnezia PoC

[jmwample]

PR allowing for drop in replacement of wireguard-go with amneziawg.

In total this is pretty straight-forward - the amnezia lib uses the same external interface but has extra (optional) arguments that are added as part of the String configuration passed in on initialization. So we swap out the library paths and then add in the options and things just work.

For now, this PR is a client change only. And as none of the servers support the more advanced features of amnezia, we cannot use handshake (init or response) message padding or header remapping yet.

All parameters should be the same between Client and Server, except Jc - it can vary.

- Jc — (1 ≤ Jc ≤ 128); recommended range is from 3 to 10 inclusive
- Jmin — (Jmin < Jmax); recommended value is 50
- Jmax — ( Jmin < Jmax ≤ 1280); recommended value is 1000
- S1 — (S1 < 1280; S1 + 56 ≠ S2); recommended range is from 15 to 150 inclusive
- S2 — (S2 < 1280); recommended range is from 15 to 150 inclusive
- H1/H2/H3/H4 — must be unique among each other;

For the Parameters that we can set there is no requirement that they match or even stay constant. So we can hard code them in for now, or (if we want) randomize them on the client on connection startup using amnezia.

What do these parameters do?

• jc - enables junk packets preceding the handshake init message
• jmin - sets the lower bound for the size of junk packets
• jmax - sets the upper bound for the size of junk packets

How does Amnezia actually differ from wireguard?

1. Junk packets can be send PRECEDING the Handshake init - the number and length of these packets is configurable.
2. Junk bytes can be PREPENDED to the handshake init message.
3. Junk bytes can be PREPENDED to the handshake response message.
4. The four Header type values can be remapped to alternate values.

Changes 2, 3, and 4 REQUIRE both client and server to run AmneziaWG with matching configuration options S1, S2, H1, H2, H3, and H4.

General Question(s)

How do we want to make this available?

• library option that can be enabled in settings in the app
• separate beta build
• auto-detect locale and try amnezia
• other?

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This change is 

[pronebird]

Been meaning to do that. We should extract args parsing into main :)

[jmwample]

I can split this out into it's own little PR

[pronebird]

That would be great!

[jmwample]

PR created here - #1432

I think it now works for the enabled build platforms

[jmwample]

I am not sure why the ios build is not finding libwg in /build/lib/aarch64-apple-ios. It could be that I missed a path replacement or implied lib name in wireguard/build-wureguard-go.sh somewhere.

[pronebird]

I am not sure why the ios build is not finding libwg in /build/lib/aarch64-apple-ios. It could be that I missed a path replacement or implied lib name in wireguard/build-wureguard-go.sh somewhere.

Try ls -la /build/lib and see what's in there

[pronebird]

Reviewable status: 0 of 26 files reviewed, 1 unresolved discussion (waiting on @jmwample)

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nym-vpn-core/crates/nym-vpn-lib/build.rs line 16 at r1 (raw file):

        .expect("failed to extract build metadata");

    let manifest_path = env::var_os("CARGO_MANIFEST_DIR").expect("manifest dir is not set");

FYI Maybe you need to rebase on main because crates/nym-wg-go already provides the linker flags, so there is no need to modify build.rs for individual targets.

[pronebird]

Reviewable status: 0 of 41 files reviewed, all discussions resolved (waiting on @aniampio)

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wireguard/build-wireguard-go.sh line 17 at r1 (raw file):

Previously, jmwample (Jack Wampler) wrote…

PR created here - #1432

I think it now works for the enabled build platforms

Thank you for that!

[pronebird]

Reviewable status: 0 of 41 files reviewed, 1 unresolved discussion (waiting on @aniampio and @jmwample)

a discussion (no related file):
Do you think there is a way we can maintain the same libwg codebase without copying all code and support amnesia at the same time?

I am not very familiar with Go toolchain. I know there things like tags for conditional compilation.

For imports, it seems that Amnezia is merely a mirror of golang.zx2c4.com/wireguard repo so maybe we could rewrite the repo URL to amnezia in go.mod while on the outside maintain the same imports from zx2c4.com.

I am not sure what the best way to tackle this, but I'd like to avoid copying the same code for as much as possible because there will be patches to the libwg and the last thing we want is to sync between libwg and amnezia fork, if possible of course.

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[jmwample]

Do you think there is a way we can maintain the same libwg codebase without copying all code and support amnesia at the same time?

This is what I tried to do first. However, I ran into trouble because the go replace directive for go.mod only allows you to replace a library with a library with the same name ("wireguard-go" != "amneziawg-go"). At the same time, the golang compiler doesn't have a pre-processor, so you can't use tags to swap library paths like you can in rust -- build tags are used to swap out entire files.

So we could use build tags and only copy the files with references to golang.zx2c4.com, or we could use a patch script and search/replace those import paths. OR we could just use the amnezia library and get rid of the wireguard-go version since it is a fork with minimal changes that by default does the exact same thing.

Only using amneziawg-go makes this PR even simpler because then the change is purely library usage, there is no build script option necessary anymore.

Edit: #1441 is an implementation of the amneziawg-go only option described above for comparison.