Heuristics on Substrate contracts pallet source language detection

contract-lang-detect.py

import sys
from ppci import wasm

m = wasm.Module(sys.stdin.buffer.read())
sections = m.get_definitions_per_section()
imports = sections['import']
start = sections['start']
customs = sections['custom']
mem = next(filter(lambda x : x.kind == 'memory', imports))

def hasName(name):
    lambda x : x.name == name

# Tentative heuristics
# (!) NOT tested with a reasonable sample set of binaries

# Solang
# * emits memory as the first import
# * has custom sections named 'name' and 'producers'
isSolang = bool(
    imports[0].kind == 'memory'
    and not start
    and customs
    and any(filter(hasName('name'), customs))
)

# Ask!
# * has a start section
# * has custom section named 'sourceMappingURL'
# * imports declare memory after functions
isAsk = bool(
    imports[0].kind != 'memory'
    and start
    and customs
    and any(filter(hasName('sourceMappingURL'), customs))
)

# Ink!
# * no custom sections
# * no start section
# * imports declare memory after functions
isInk = bool(
    imports[0].kind != 'memory'
    and not start
    and not customs
)

print(f"""
Detection results
-----------------
Ink! = {isInk}
Ask! = {isAsk}
Sol  = {isSolang}
""")

example-output.txt

❯ python3 contract-lang-detect.py < blobs/flipper.ink.wasm 

Detection results
-----------------
Ink! = True
Ask! = False
Sol  = False

❯ python3 contract-lang-detect.py < blobs/flipper.ask.wasm

Detection results
-----------------
Ink! = False
Ask! = True
Sol  = False

❯ python3 contract-lang-detect.py < blobs/flipper.sol.wasm 

Detection results
-----------------
Ink! = False
Ask! = False
Sol  = True

wasm-blobs.zip