edeco

fuc & xtensa deasm flow detector. Second incarnation.

Requires Python 2.7+

For current usage, refer to edeco.py -h.

usage: edeco.py [-h] -m {fuc,xtensa} [--cmap CMAP] [-x] [-f FUNCTION] deasm deco

positional arguments: deasm input deasm file deco output decompiled file

required arguments: -m {fuc,xtensa}, --microcode {fuc,xtensa} microcode name

optional arguments: -h, --help show help message and exit --cmap CMAP code space map file -x, --no-autodetect Don't autodetect functions -f FUNCTION, --function FUNCTION Function address: decimal (123) or hex (0x12ab)

What it does: Takes a deasm file, analyzes gotos and outputs a nicely formatted flow structure (asm pieces inside C-like braces where appropriate). works with arbitrarily entangled control flow.

Gotchas: This version of the program does not cope well with goto/break/return - these break hierarchical control flow and it's not really possible to determine whether they are exits in terms of original C-like source code. Therefore they will always be followed until a single exit is found, which might make output messy. The lightest example is switch (first single exit at the end of statement) interpreted as a chain of if{}else{if{}else{...}}, the heaviest is a return from within a loop (first single exit is the end of the function) - total mess. Some of that might get improved in the future via smart guessing or hiding of control-only code.

What it will do again:

• recognize simple control flow structures
• find call addresses
• generate pseudocode for store instructions
• find and label memory structures

What new it could do:

• analyze data flow
• find branch conditions
• hide ASM blocks only used for control flow (and simplify flow graph further)
• find iowr/iost addresses
• find loop invariants
• become an emulator
• take into account custom memory labels and function names
• become interactive