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Application Protocol

As the previous pages have eluded to (you did read them, didn't you?), eAmuse uses HTTP as its main way of getting data around. This means we need an HTTP server running but, as we'll see, we don't need to think too hard about that.

Every request made is a POST request, to //<model>/<module>/<method>, with its body being encoded data as described in the previous sections. In addition to the X-Compress: and X-Eamuse-Info: headers previously detailed, there is also a X-PCB-ID: header. that can be set. Your machine's PCB ID uniquely defines the physical board. This header is added in out-bound requests, and allows the server to identify you. Importantly, it's also the value that the server uses to identify which machines are authorized to be on the network, and which are not.

Every request is followed immediately by a response. Any response code other than 200 is considered a failure.

Source code details
libavs-win32-ea3.dll:0x1000f8e7

All requests follow a basic format:

<call model="model" srcid="srcid" tag="tag">
    <module method="method" ...attributes>
        children
    </module>
</call>

The responses follow a similar format:

<response>
    <module status="status" ...attributes>
        children
    </module>
</response>

With "0" being a successful status. Convention is to identify a specific method as module.method, and we'll be following this convention in this document too. There are a lot of possible methods, so the majority of this document is a big reference for them all. There are a number of generic methods, and a number of game specific ones. If you haven't clocked yet, I've been working on an SDVX 4 build for most of these pages, and each game also comes with its own set of game-specific methods. These are namespaces under the game.%s module and, in the case of SDVX 4, are all game.sv4_method. I may or may not document the SDVX 4 specific methods, but I've listed them here anyway for completeness.

Paths in the XML bodies are formatted using an XPath-like syntax. That is, status@/response gets the status attribute from response, and response/eacoin/sequence would return that node's value.

NOTE: I am using the non-standard notation of <node* ... and <node attr*="" ... to indicate that an attribute or node is not always present! Additionally, I am going to use the notation of <node[]> to indicate that a node repeats.

Status Meaning
0 Success
109 No profile
110 Not allowed
112 Card not found (cardmng.inquire)
116 Card pin invalid (cardmng.authpass)
How to reverse engineer these calls

Turns out bemani have been quite sensible in how they implemented their code for creating structures, so it's rather readable. That said, if you've been using Ghidra (like me!), this is the time to switch to IDA. I'll let the below screenshots below speak for themselves:

Ghidra
IDA Pro

I know which of these I'd rather use for reverse engineering (sorry, Ghidra)!

Possible XRPC requests

Totally undocumented services (based on services.get):

I'll try and figure these out in due course, promise!

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