Multiplayer Homebrew Development

Discussion in '3DS - Homebrew Development and Emulators' started by vinnyboiler, Apr 2, 2015.

  1. vinnyboiler
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    vinnyboiler Member

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    I noticed something peculiar about the 3DS Download Play application. Namely that I can get modded MK7 tracks though to my nephews 3DS despite it having the latest firmware.

    This have got me interested in seeing if it's possible to send 3DS homebrew packets in form as data from modded games that support Download Play.

    I was wondering if anyone has looked into the Download Play service and how it can be used to enhance homebrew. Going to it's wiki page on 3dbrew, it appears that the host 3ds broadcasts a .CIA file that contains" a certificate chain, a ticket, a TMD, and the actual application itself, in CXI format." I'm wondering if it's possible to switch out the CXI with another.

    I'm not smart when it comes to this kind of stuff which is why I'm asking for more help on this.
     
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  2. DarkFlare69

    DarkFlare69 GBAtemp Psycho!

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    How exactly did you get the modded tracks onto your Nephews 3DS from your own?..
     
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  3. vinnyboiler
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    vinnyboiler Member

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    1) Created a CIA file with MKGirlism's "DS Figure-8 Circuit Beta 0.2".
    2) Imported the CIA into my Gateway enabled 3DS.
    3) Stated the game and gone into local multiplayer.
    4) Created a group.
    5) On my nephew's 3DS I selected the Download Play app and had it searched for the game
    6) Have it connect to the game

    Once that is done, going onto the Toad Circuit track has it instead go onto the modded track on both 3DS's.

    It appears based on this that the 3DS does not have the same protection the DS had which prevented it from running modified files.
     
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  4. DarkFlare69

    DarkFlare69 GBAtemp Psycho!

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    Interesting. Has anyone tried using CTs online?
     
  5. Memoir

    Memoir A Hero to Zero

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    I don't believe that'll work. With download play you're sending that data to the client 3ds. So, I'm assuming the track data goes with it. Now, if he were to try this with 2 copies of the game and it worked? That'd lead to some interesting things.
     
  6. DarkFlare69

    DarkFlare69 GBAtemp Psycho!

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    Can anyone try doing it with 2 copies of the game?
     
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  7. mid-kid

    mid-kid GBAtemp spamBOT

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    Wait, I believed download play data to be on a different partition in the ROM?
    I don't think anyone is editing that.
     
  8. vinnyboiler
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    vinnyboiler Member

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    Well from what happened with MK7 it appears that the data gathered for download play is just the same data from the main partition of the ROM.

    It looks like a few NES virtual console games like Ice Climber and Balloon Fight have a download play feature. If it works the same way as MK7 then ideally I can get other 2 player NES games to work by injecting them into one of these CIA's.
     
  9. Magicrafter13
    This message by Magicrafter13 has been removed from public view by BORTZ, Apr 13, 2017.
    Apr 12, 2017