Hack 95 Browsing Through TiVo's Resources

Groups of resources are loaded by TiVo's main programs at runtime. Hacking these resources allows customization of the TiVo software without recompiling or any such complex shenanigans.

Resource groups are external definitions of strings that the main program can load at runtime, allowing programmers to customize applications in various ways without touching the executable applications themselves. Normally these resources are meant for TiVo, Inc. programmers, but now they in the hands of hackers.

You can browse the current crop of resource groups on your TiVo in /SwSystem/ACTIVE. Use mls [Hack #88] to inspect the file. Then use dumpobj [Hack #89] to view their contents:

% mls /SwSystem/ACTIVE
Directory of /SwSystem starting at 'ACTIVE'

    Name Type FsId Date Time Size    
    ---- ---- ---- ---- ---- ----    
    ACTIVE tyDb 1054901 06/14/02 07:04 652    

% dumpobj /SwSystem/ACTIVE
SwSystem 1054901/11 {
  Active         = 1
  IndexPath      = /SwSystem/3.0-01-1-010 /SwSystem/ACTIVE /Server/6406408
  Module         = 1054552/-1 1054554/-1 1054556/-1 1054558/-1 1054560/-1 
1054562/-1 1054564/-1 1054566/-1 1054902/-1
  Name           = 3.0-01-1-010
  ResourceChecksum = 2561393d51da083831d2f0714914888a
  ResourceGroup  = 1054757/-1 1054758/-1 1054889/-1 1054761/-1 1054766/-1 
1054767/-1 1054890/-1 1054772/-1 1054775/-1 1054776/-1 1054779/-1 1054891/-1 
1054784/-1 1054787/-1 1054892/-1 1054792/-1 1054795/-1 1054796/-1 1054800/-1 
1054893/-1 1054803/-1 1054806/-1 1054807/-1 1054808/-1 1054809/-1 1054894/-1 
1054810/-1 1054895/-1 1054896/-1 1054897/-1 1054811/-1 1054812/-1 1054813/-1 
1054814/-1 1054815/-1 1054816/-1 1054817/-1 1054818/-1 1054821/-1 1054898/-1 
1054826/-1 1054899/-1 1054831/-1 1054900/-1 1054840/-1 1054841/-1 1054850/-1 
1054851/-1 1054854/-1
  ServerId       = 6406408
  ServerVersion  = 51
  Version        = 2
}

FSIDs of all the available resource groups are listed under ResourceGroup. Here, you'll find all the text in the TiVo user interface, constants that control your MPEG encoder bitrate, the backdoor password [Hack #8], a veritable cornucopia of default values, and a host of things nobody has yet figured out.

The Code

The following script is based on a conversation at http://alt.org/forum/index.php?t=msg&th=34. It walks through all the resources in the TiVo and prints them out with their identification numbers

#!/tvbin/tivosh                  

set outformat "%3s %3s %s"
puts [format $outformat "GID" "IID" "Resource"]
puts [format $outformat "---" "---" "--------"]
                  
set db [dbopen]   
RetryTransaction {
    set active [db $db open "/SwSystem/ACTIVE"] 
    set rgroup [dbobj $active get ResourceGroup]
    set groupn 0  
    foreach group $rgroup { 
        set items [dbobj $group get Item]
        set itemn 0
        foreach item $items {
        regsub -all "\[\{\}\]" [dbobj $item get String] "" resource[RETURN]
        puts [format $outformat $groupn $itemn "\"$resource\""][RETURN] 
        incr itemn                                                           
        }         
        incr groupn
    }             
}

Save the code as dump.tcl in your TiVo's /var/hack/bin directory and make it executable, like so:

bash-2.02# chmod 755 /var/hack/bin/dump.tcl

Running the Hack

Run the script from TiVo's command line Section 3.3. You're sure to see lots of familiar strings flow by.

bash-2.02# /var/hack/bin/dump.tcl
...
  1   5 "Now Playing List"
  1   6 "TiVo Central"
  1   7 "TiVo's Suggestions"
  1   8 "TiVolution Magazine"
  1   9 "Showcases"
  1  10 "Pick Programs to Record"
  1  11 "To Do List"
  1  12 "Messages & Setup"
  1  13 "DIRECTV Menu"
  1  14 "No programs"
  1  15 "TiVolution Magazine is currently unavailable. It will be updated 
the next time your Recorder makes a daily call to the TiVo Service. "
  1  16 "Custom"
  1  17 " Channel %s"
  1  18 " Search By Title"
  1  19 " Browse By Channel"
  1  20 " Browse By Time"
  1  21 " Search Using WishLists"
  1  22 " Manually Record Time/Channel"
...

Just makes you want to reach out and fiddle [Hack #96], doesn't it?