These are the known OFP file formats.
File format generic data types (link to ArmA namespace)
WRP general info
WRP - 1WVR
WRP - OPRW
WRP - OPRW 2 and 3
WRP - 4WVR
P3D general info
PBO
ODOL
MLOD
FXY
raP
RTM Animation
Stringtable.csv
Description.ext