obfuscate all variable names, even local ones #420
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In the added test case, "garble -literals build" would fail:
--- FAIL: TestScripts/literals (8.29s)
testscript.go:397:
> env GOPRIVATE=test/main
> garble -literals build
[stderr]
# test/main
Usz1FmFm.go:1: cannot call non-function string (type int), declared at Usz1FmFm.go:1
Usz1FmFm.go:1: string is not a type
Usz1FmFm.go:1: cannot call non-function append (type int), declared at Usz1FmFm.go:1
That is, for input code such as:
var append int
println("foo")
_ = append
We'd end up with obfuscated code like:
var append int
println(func() string {
// obfuscation...
x = append(x, ...)
// obfuscation...
return string(x)
})
_ = append
Which would then break, as the code is shadowing the "append" builtin.
To work around this, always obfuscate variable names, so we end up with:
var mwu1xuNz int
println(func() string {
// obfuscation...
x = append(x, ...)
// obfuscation...
return string(x)
})
_ = mwu1xuNz
This change shouldn't make the quality of our obfuscation stronger,
as local variable names do not currently end up in Go binaries.
However, this does make garble more consistent in treating identifiers,
and it completely avoids any issues related to shadowing builtins.
Moreover, this also paves the way for publishing obfuscated source code,
such as burrowers#369.
Fixes burrowers#417.
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lu4p
approved these changes
Nov 16, 2021
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