Piloted ship transport mechanism

[jpcsupplies]

A method has been found that allows ships to travel with players to other servers. Limitations;

1. Ownership on arrival automatically changes to the player piloting the ship due to players having unique IDs on each server world which become meaningless on the new server.
2. Players can only depart alone. (although other players can depart from the same debarkation point, they have to trigger the process individually.) This is because the type of subs that trigger the event only seem to work from a message command. This appears to be some odd glitch with the server connect modapi function. Area events (including all players) don't seem to be compatible.
3. Both servers must be running the Lobby Gateway mod.
4. Optionally -each server must use a shared authentication key to authenticate that a player is allowed to take his ship there.

Tech summary:

• [ ] On triggering depart event, a copy of the players current ship needs to be written to an xml file client side. This MUST include cargo details. Otherwise unpowered ships, missing all their loot on arrival will cause rage!
• [ ] some visual effect such at the jump drive effect or a similarly iconic visual effect and sound should be triggered while the player waits for the transfer process to begin.
• [ ] Security: (added last for tech demo security can be initially omitted) A passcode set by the admin of the server is used to generate an authentication code to sign the xml copy of the ship, this code is added to the xml file with the ship It should also include in the coding process some sort of CRC type figure to confirm the ship xml data has not been tampered with! Coding tech is simply a case of converting some code (such as the player steam ID, the crc info, and the target location ID code and some special code derived from the secret passcode) into an array of long integers. (convert to ascii, concatinate ascii codes into groups of long (16 chars) integers) these integers then need to be multiplied by another long integer set based on the passkey. To convert back divide by the passcode result on the new server which then should when converted to ascii back to characters decode the data.
• [ ] The players ship needs to be deleted from the original server
• [x] The connection to the new server is triggered
• [ ] On join the server connects to the client side of the mod and checks if there is any "ship transit" file
• [ ] -omit for initial tech demo- The server extracts the authentication code from the xml and attempts to decode it.
• [ ] -If the code checks out, if used- request the client send the xml data to the server
• [ ] The server converts the xml data into a ship, and spawns in the player and the ship (with the player IN the ship) \ The spawned ship will either have no ownership info or be set to the pilots ID, as migrated owner IDs will be unlikely to match up with codes for players on the new server. Preferred behavior is set ownership to pilot - since this will prevent any turrets shooting them down on the new server. Depending on mod api it might be possible to resolve owner ids to steam ids and write those to the xml file, then attempt to match the steam ids to local player ids on the new server - but this is a lot of work best done after everything else is working. My knowledge of modapi suggests that setting individual block ownership is nearly impossible, while setting entire grid ownership is already possible - so most likely arriving ships will have pilot set as owner or set to nobody. (probably make that configurable)
• [ ] The server instructs the client to remove the xml data file now that the ship has suceeded in spawning
• [ ] If the authentication fails, leave the xml copy of the ship in the client side data, in case they return to the original server again so they do not lose their ship on an unauthorised server.
• [ ] Optional on arrival and all checks out, prior to spawning ship generate some visual effect at the arrival point ?
• [ ] optional record extra info such as the suggested gps location or better yet an alias representing the suggested location near which the ship and player should spawn on the new server
• [ ] optional on each server create an alias list of gps locations for ships arriving from other servers to be spawned near as appropriate - this allows for example a player departing from an asteroid cluster on one server to be spawned in an asteroid cluster roughly in the same direction as the previous server fictionally represents that they arrived from.
• [ ] optional support an "allow all" directive that can be configured by admin that allows ships to spawn even if there is no valid authentication code *\ Note this will be the default behavior in the first tech demo of this process most likely since authentication most likely wont be added yet
• [ ] optional support a list of passcodes server side that allows one server to allow ships to depart to multiple authenticated servers
• [ ] passcodes only exist server side, and only the admins know what this code is, clients only ever see the coded data, not the passcode that encoded it. This means only admins who share the password between their respective servers will allow players to travel with their ships between them; and this passcode being server side is never exposed client side to the players
• [ ] optional - integrating with economy the encoding process could also store a desired quantity of currency along with the ship data to be transferred with the ship to the new server
• [ ] optional - require the ship to have a jump drive or similar block and/or drain its jump power on arrival at new server

[jpcsupplies]

Basic coding tech summary:

• Admin sets a secret code server side - this code is used on servers players are permitted to travel between. Only server admins know this code.
• code is converted to ascii codes which are concatenated to form a long integer.
• numbers resulting from multiples and division need to be whole so rounding and/or primes may be needed
• any data such as player steam id plus any crc check values and target alias ids or economy "cheque" amounts and a random value derived from secret code or a second code is used to taint data to prevent brute force by knowing its contents is likewise converted to ascii codes and concatenated in groups of 8, 16, or 32 characters to form long integers \ tainting could also involve running additional iterations over the data prior to writing to xml exponentially increasing the number of passes required to brute force, at the encoding stage this adds only ms's to encoding process
• these long integers are multiplied by the long integer formed by the secret code (or codes) and written to the xml file formed by the ship data

decoding is the reverse of the process, except dividing not multiplying

\ if the secure/crypto library includes are available in modapi it may also be possible to use full public/private key md5 system, or it could be manually implemented in full which is similar to the above but makes greater use of factorial pairs for the multiplication divs and mod calculations to form public/private key pairs - ie refer http://doctrina.org/How-RSA-Works-With-Examples.html

[jpcsupplies]

Suggested Admin requirement:

1. Install mod
2. On first boot of server run a command like /password your_server_password_here
3. create a departure LCD to another server that uses that same password
4. Optional - create an "arrival zone" or simply randomise it.

Thats pretty much it. A player flies into a departure point hits the /depart command and off they go ship and all to the new server. Could treat it like long range jump points..

[jpcsupplies]

For reference: (from chat)

If we skip the security layer (as its proof of concept) all the mod needs to do is: 1: Have a definable region where the mod detects a player entering in a piloted ship (eg a super gate, jump point, or simply a lcd etc) 2: This definable area notifies the player they could type /travel to jump to this server 3: game breaks down the ship to an xml file (client side) stored in global storage and deletes it (server side) ideally it doesnt delete client side so a player isnt booted into space; (breaks immersion) but no longer exists if any other player flies past. 4: game uses existing connect to other server modapi call to send player to new server 5: after connect the mod checks for the client side global file with the ship in it 6: if it exists it tells the server side version of the mod and passes it across 7: server spawns the ship and teleports the player into it 8: client side copy of file is deleted on confirmation of sucess spawning ship(edited) something like that

[jpcsupplies]

see also #11

[jpcsupplies]

Rexxar build a mod that implements our client side discussion aspects of ship transfer between servers here: http://steamcommunity.com/sharedfiles/filedetails/?id=912773575

He put it up on git here : https://github.com/rexxar-tc/ServerLinkMod