Commit Graph

9 Commits (c5af68cd802f0191219bd705de785dde46a3d819)

Author SHA1 Message Date
lu4p 1526ce7fd2
rework reflection detection with ssa (#732)
This is significantly more robust, than the ast based detection and can
record very complex cases of indirect parameter reflection.

Fixes #554
1 year ago
Daniel Martí b0ff2fb133 fix encoding/asn1 marshaling of pkix types
See the added comment and test, which failed before the fix when
the encoded certificate was decoded.

It took a while to find the culprit in asn1, but in hindsight it's easy:

	case reflect.Slice:
		if t.Elem().Kind() == reflect.Uint8 {
			return false, TagOctetString, false, true
		}
		if strings.HasSuffix(t.Name(), "SET") {
			return false, TagSet, true, true
		}
		return false, TagSequence, true, true

Fixes #711.
1 year ago
Daniel Martí e6fc593f68 set testscript's RequireExplicitExec and RequireUniqueNames
The first makes our test scripts more consistent, as all external
program executions happen via "exec" and are not as easily confused
with custom builtin commands like our "generate-literals".

The second catches mistakes if any of our txtar files have duplicate
files, where all but one of the contents would be ignored before.
1 year ago
Daniel Martí b322876efe drop support for Go 1.19
Now that we're done with garble v0.9.x,
v0.10 will only support Go 1.20 as a minimum version.
1 year ago
Daniel Martí 5effe20c19 avoid breaking github.com/davecgh/go-spew
It assumes that reflect.Value has a field named "flag",
which wasn't the case with obfuscated builds as we obfuscated it.

We already treated the reflect package as special,
for instance when not obfuscating Method or MethodByName.
In a similar fashion, mark reflect's rtype and Value types to not be
obfuscated alongside their field names. Note that rtype is the
implementation behind the reflect.Type interface.

This fix is fairly manual and repetitive.
transformCompile, transformLinkname, and transformAsm should all
use the same mechanism to tell if names should be obfuscated.
However, they do not do that right now, and that refactor feels too
risky for a bugfix release. We add more TODOs instead.

We're not adding go-spew to scripts/check-third-party.sh since the
project is largely abandoned. It's not even a Go module yet.
The only broken bit from it is what we've added to our tests.

Fixes #676.
1 year ago
Daniel Martí 9c0cdc61ef avoid reflect method call panics with GOGARBLE=*
We were obfuscating reflect's package path and its declared names,
but the toolchain wants to detect the presence of method reflection
to turn down the aggressiveness of dead code elimination.

Given that the obfuscation broke the detection,
we could easily end up in crashes when making reflect calls:

	fatal error: unreachable method called. linker bug?

	goroutine 1 [running]:
	runtime.throw({0x50c9b3?, 0x2?})
		runtime/panic.go:1047 +0x5d fp=0xc000063660 sp=0xc000063630 pc=0x43245d
	runtime.unreachableMethod()
		runtime/iface.go:532 +0x25 fp=0xc000063680 sp=0xc000063660 pc=0x40a845
	runtime.call16(0xc00010a360, 0xc00000e0a8, 0x0, 0x0, 0x0, 0x8, 0xc000063bb0)
		runtime/wcS9OpRFL:728 +0x49 fp=0xc0000636a0 sp=0xc000063680 pc=0x45eae9
	runtime.reflectcall(0xc00001c120?, 0x1?, 0x1?, 0x18110?, 0xc0?, 0x1?, 0x1?)
		<autogenerated>:1 +0x3c fp=0xc0000636e0 sp=0xc0000636a0 pc=0x462e9c

Avoid obfuscating the three names which cause problems: "reflect",
"Method", and "MethodByName".

While here, we also teach obfuscatedImportPath to skip "runtime",
as I also saw that the toolchain detects it for many reasons.
That wasn't a problem yet, as we do not obfuscate the runtime,
but it was likely going to become a problem in the future.
2 years ago
Daniel Martí 481e3a1f09 default to GOGARBLE=*, stop using GOPRIVATE
We can drop the code that kicked in when GOGARBLE was empty.
We can also add the value in addGarbleToHash unconditionally,
as we never allow it to be empty.

In the tests, remove all GOGARBLE lines where it just meant "obfuscate
everything" or "obfuscate the entire main module".

cgo.txtar had "obfuscate everything" as a separate step,
so remove it entirely.

linkname.txtar started failing because the imported package did not
import strings, so listPackage errored out. This wasn't a problem when
strings itself wasn't obfuscated, as transformLinkname silently left
strings.IndexByte untouched. It is a problem when IndexByte does get
obfuscated. Make that kind of listPackage error visible, and fix it.

reflect.txtar started failing with "unreachable method" runtime throws.
It's not clear to me why; it appears that GOGARBLE=* makes the linker
think that ExportedMethodName is suddenly unreachable.
Work around the problem by making the method explicitly reachable,
and leave a TODO as a reminder to investigate.

Finally, gogarble.txtar no longer needs to test for GOPRIVATE.
The rest of the test is left the same, as we still want the various
values for GOGARBLE to continue to work just like before.

Fixes #594.
2 years ago
Daniel Martí 58b2d64784 drop support for Go 1.18.x
With Go 1.19 having been out for two months,
and Go 1.20's first beta coming out in two months,
it is now time to move forward again.
2 years ago
Daniel Martí 99c12e396a replace testdata/scripts/*.txt with testdata/script/*.txtar
Following the best practices from upstream.
In particular, the "txt" extension is somewhat ambiguous.

This may cause some conflicts due to the git diff noise,
but hopefully we won't ever do this again.
2 years ago