t5de-proxy

T5DE's local proxy for IMVU Classic. With T5DE's t5de-proxy patch, the client starts t5de-proxy.exe and connects to IMVU through it:

• Every HTTP request, the embedded browser's included (IMVU's browser hands its requests to the client's Python). The proxy makes them with current TLS and root certificates (the client has only IMVU's bundled certificates and TLS 1.2), pooled connections and HTTP/2.
• HTTPS for IMVU hosts the client reaches over plain HTTP (its XML-RPC API, images, CSS), so its account headers don't cross the network in the clear (docs/hosts.md).
• IMQ, IMVU's chat and presence connection: the client speaks plaintext to the proxy, which connects to the gateway over TLS.
• IMVU's reporting endpoints refused, as T5DE's patches already do in the client.
• Community products from local packs (t5de-api's pack format), kept away from IMVU (below).

If the proxy isn't there or stops, the client connects directly, as before.

Unofficial: not made by or affiliated with IMVU.

How it works

The proxy listens on a free port of 127.0.0.1 and accepts only requests carrying the token it gave the client (Proxy-Authorization: Basic t5de:<token>), so other programs and web pages can't use it.

• HTTP: requests in absolute form (GET https://api.imvu.com/... HTTP/1.1) over plain HTTP on loopback, for http and https URLs alike. Responses come back as the server sent them: redirects aren't followed, bodies aren't decompressed. When the proxy can't reach a server it answers 502 with X-T5de-Proxy-Error, which the client raises as the network error it would have had connecting directly.
• CONNECT host:port: the client then speaks plaintext and the proxy connects to host:port over TLS. The proxy reads IMQ's framing (message type and size, not contents) to log it.

The client starts it as t5de-proxy -parent <pid> -ready <file> -log %TEMP%\t5de-proxy.log; it writes its address and token to the ready file once listening, and exits with the client. Setting T5DE_PROXY_TRACE=1 before starting the client adds full URLs (with queries) and every IMQ frame to the log.

Community products

Phase 1 of T5DE's community products (design: t5de-hub's docs/design.md): products in local packs, a folder each, in %APPDATA%\T5DE\packs and the folders in T5DE_PACKS (separated by ;). Each product gets a local ID from 2,000,000,000 up, kept in %APPDATA%\T5DE\proxy\products.json. For those IDs the proxy answers the client itself:

• test.inventoryProductBatch (product info) and test.authorizeProducts2 (permission, the CFL's address and checksum): for a product deriving from an IMVU product, IMVU is asked about the parent and the proxy adds its own entry (the client needs the parent's derivation chain).
• productdata/<local ID>/<revision>: the pack built into a CFL.
• api/shop/product.php: putting a product on asks whether it's a bundle (not), and the shop asks for product details (answered from the hub's listing, or the pack; IMVU is asked only about its own products).

IMVU never sees community products: they're taken out of outfit saves (api/base_look.php) and outfit chat commands (*use, *putOn, *putOnOutfit, *remove, *takeOff on /chat/ queues; a command left empty is answered by the proxy), so IMVU and everyone else see the defaults. The proxy remembers each account's community products with the outfit they were saved with, and adds them back when the client loads that same outfit (base_look.php, and look in the login response); an outfit changed elsewhere comes back without them. Requests it changes are re-signed (X-imvu-auth) with the session key from the login response, which never leaves the machine. The client sends some product IDs as floats (2000000008.0), so every ID is read either way (parseID). As a last check, products.Guard refuses any request to IMVU that still names a local ID given out, and logs it (products: refused a request to ...): such a request is a path not handled yet.

The hub

The client's Settings > T5DE page signs in and out (the proxy answers it at http://t5de-proxy.local/hub, internal/control). t5de-proxy signin [-hub URL] also signs the proxy in to T5DE's hub (git.t5de.dev/t5de/t5de-hub; URL is the hub's API): it shows a code to enter on the hub's website (/device, OAuth 2.0 device authorization) and saves the session token it gets in %APPDATA%\T5DE\proxy\hub.json, encrypted for the Windows user (DPAPI). From then on the running proxy keeps a WebSocket to the hub (internal/hub) with the token as a bearer token, reporting which IMVU account the client signed in as, the community products it wears, and the IMVU chats it's in. If the hub ends the session (signed out everywhere, banned), the proxy stops connecting until signin is run again.

The room channel (internal/products/room.go): the hub tells the proxy which other T5DE users are in the same chat and what they wear; the proxy gives the client those of their products it has packs for, as *use/*remove lines from them, and adds them to the whole outfits they send. It also keeps community products out of the outfit the client posts to IMVU's chat participant endpoint.

The shop (the client's t5de-shop patch adds a T5 choice to its rating filter): searches with maturity_rating t5 (api/shop/search_st.php) are answered from the hub's products (GET /api/v1/products, filtered by the shop's categories against each product's IMVU parent's category path), fetching listed products that aren't here yet (up to 15 seconds) so they can be shown and tried on. Buying T5 products (api/service/shop/svc_catalog_purchase.php) adds them to the person's hub library; IMVU products in the same purchase go on to IMVU without them.

For finding out what IMVU's APIs send, T5DE_PROXY_DUMP=<text> logs the request and response bodies of requests whose path contains it (test accounts only: bodies hold personal data). In Git Bash, keep the value from starting with / (or set MSYS_NO_PATHCONV=1), or it's turned into a Windows path.

Building

go test ./...
GOOS=windows GOARCH=amd64 go build -trimpath -ldflags "-H=windowsgui" -o dist/t5de-proxy.exe ./cmd/t5de-proxy

CI publishes t5de-proxy.exe: pushes to main replace the nightly pre-release, vX.Y.Z tags make releases. To ship a release in T5DE, copy its url and sha256 into t5de's t5de.toml ([[programs]], patch t5de-proxy).