Help Needed: Identifying Structure of Packet 0x0D00 After Character Selection (PACKETVER 20230302)

[KaingKyungWan]

Hello rAthena Community,

I'm currently developing a Unity client for an rAthena-based server (PACKETVER 20230302) and I've encountered an unknown packet after character selection.

Here's the sequence of packets I'm successfully parsing from the character server:
1. Login and authentication packets (e.g., 0x0065 response)
2. Character slot info (e.g., 0x082D)
3. Character list data (0x006B) - Parsed successfully, character details are correct.
4. Character list page info (0x09A0) - Parsed successfully.

Immediately after processing the 0x09A0 packet, my client receives a packet with ID `0x0D00`.
My client logs show the following for this `0x0D00` packet:
- Packet ID: `0x0D00`
- Declared total length (from bytes 2-3 of the packet): `29` (0x001D)
- This means the data payload (excluding the 2-byte ID and 2-byte length field) is `25` bytes.

The HEX dump of this 25-byte data payload is:
`0F 00 00 0F 0F 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00`

I've searched through my rAthena server source files (including `char_clif.c`, `mmo.h`, `packets.hpp`, etc.) but I cannot find any explicit definition or usage of a packet with the ID `0x0D00` that would be sent from the character server to the client after character selection with this specific length and payload.

I suspect this `0x0D00` packet contains crucial information for connecting to the map server (e.g., selected Character ID for map server, Map Server IP, Port, and session/auth keys). However, without knowing its structure, I cannot parse it correctly. My current attempts to parse it based on common map server info structures with a 25-byte payload yield unusual values (e.g., Map IP 15.0.0.0, Port 0).

Could anyone please help me identify the structure of this `0x0D00` packet (with a 25-byte payload) that is sent after character selection? Specifically, what do these 25 bytes represent?
Is this a standard rAthena packet for a specific `PACKETVER` (my server is `20230302`), or could it be a custom packet?

Any insights or pointers to relevant source code sections would be greatly appreciated.

Thank you!

[Toshiro]

Are you sure the packets before 0x0D00 are being read correctly? The highest packet number on official clients (last month) are around 0x0C30, so 0x0D00 for a two year old packet version does not seem correct.