Commit Graph

655 Commits (d2beda1f0016a11b0b0a364eff06a153eb4a448a)
 

Author SHA1 Message Date
Daniel Martí 1db6e1e230
make -coverprofile include toolexec processes (#216)
testscript already included magic to also account for commands in the
total code coverage. That does not happen with plain tests, since those
only include coverage from the main test process.

The main problem was that, before, indirectly executed commands did not
properly save their coverage profile anywhere for testscript to collect
it at the end. In other words, we only collected coverage from direct
garble executions like "garble -help", but not indirect ones like "go
build -toolexec=garble".

	$ go test -coverprofile=cover.out
	PASS
	coverage: 3.6% of statements
	total coverage: 16.6% of statements
	ok  	mvdan.cc/garble	6.453s

After the delicate changes to testscript, any direct or indirect
executions of commands all go through $PATH and properly count towards
the total coverage:

	$ go test -coverprofile=cover.out
	PASS
	coverage: 3.6% of statements
	total coverage: 90.5% of statements
	ok  	mvdan.cc/garble	33.258s

Note that we can also get rid of our code to set up $PATH, since
testscript now does it for us.

goversion.txt needed minor tweaks, since we no longer set up $WORK/.bin.

Finally, note that we disable the reuse of $GOCACHE when collecting
coverage information. This is to do "full builds", as otherwise the
cached package builds would result in lower coverage.

Fixes #35.
3 years ago
Andrew LeFevre e014f480f9
if the seed is random and the build fails, print the seed (#213)
Fixes #212
3 years ago
lu4p 91deb1e224
Document reflect.TypeOf hint (#211)
* Document reflect.TypeOf hint

Fixes #163

* Fix nit
3 years ago
Andrew LeFevre 2d720ae155
fixed some bugs related to additional linkname corner cases (#210) 3 years ago
Daniel Martí 835f4aadf3
testdata: add test case for init funcs in many files (#208)
We tested that init funcs within a single file retain their order, but
not when they are split between many files.

Add one such case, with ten files and the same global-var-append
mechanism.

While at it, add some docs and make each init func take just one line.
4 years ago
Daniel Martí 8cae98ca1b
mod: bump dependencies (#207)
Nothing too special, as all tests pass the same.
4 years ago
Daniel Martí f667a7ad31
all: use better names than "blacklist", and docs (#206)
The three transformer map fields are now very well documented, which was
badly needed for anyone trying to understand the source code.

ignoreObjects is also a better field name than blacklist, as it says
what the map is indexed by (types.Object) and what we do with those:
ignore them when we obfuscate code.

The rewriting of go:linkname directives is moved to a separate func, so
that we can name that func from the docs.

Finally, the docs are overall improved a bit, as I was re-tracing all
the pieces of code that used the ambiguous "blacklist" terminology.

Fixes #169.
4 years ago
Daniel Martí ff3d62f9c3
prevent exiting early with early errors (#205)
The point of main1 returning an int is that testscript can run code
afterwards, such as to collect coverage information when running with
-coverprofile.

We were using plain os.Exit in a couple of places: when help was
requested, and when the Go version could not be fetched.

In those cases, return an error to main1, and let it do the right thing.

For #35.
4 years ago
Daniel Martí ba19a1d49c
do not try to obfuscate huge literals (#204)
It's common for asset bundling code generators to produce huge literals,
for example in strings. Our literal obfuscators are meant for relatively
small string-like literals that a human would write, such as URLs, file
paths, and English text.

I ran some quick experiments, and it seems like "garble build -literals"
appears to hang trying to obfuscate literals starting at 5-20KiB. It's
not really hung; it's just doing a lot of busy work obfuscating those
literals. The code it produces is also far from ideal, so it also takes
some time to finally compile.

The generated code also led to crashes. For example, using "garble build
-literals -tiny" on a package containing literals of over a megabyte,
our use of asthelper to remove comments and shuffle line numbers could
run out of stack memory.

This all points in one direction: we never designed "-literals" to deal
with large sizes. Set a source-code-size limit of 2KiB.

We alter the literals.txt test as well, to include a few 128KiB string
literals. Before this fix, "go test" would seemingly hang on that test
for over a minute (I did not wait any longer). With the fix, those large
literals are not obfuscated, so the test ends in its usual 1-3s.

As said in the const comment, I don't believe any of this is a big
problem. Come Go 1.16, most developers should stop using asset-bundling
code generators and use go:embed instead. If we wanted to somehow
obfuscate those, it would be an entirely separate feature.

And, if someone wants to work on obfuscating truly large literals for
any reason, we need good tests and benchmarks to ensure garble does not
consume CPU for minutes or run out of memory.

I also simplified the generate-literals test command. The only argument
that matters to the script is the filename, since it's used later on.

Fixes #178.
4 years ago
Daniel Martí 249501b5e9
fix garbling names belonging to indirect imports (#203)
main.go includes a lengthy comment that documents this edge case, why it
happened, and how we are fixing it. To summarize, we should no longer
error with a build error in those cases. Read the comment for details.

A few other minor changes were done to allow writing this patch.

First, the actionID and contentID funcs were renamed, since they started
to collide with variable names.

Second, the logging has been improved a bit, which allowed me to debug
the issue.

Third, the "cache" global shared by all garble sub-processes now
includes the necessary parameters to run "go list -toolexec", including
the path to garble and the build flags being used.

Thanks to lu4p for writing a test case, which also applied gofmt to that
testdata Go file.

Fixes #180.
Closes #181, since it includes its test case.
4 years ago
lu4p 2e2bd09b5e Simplify maps to boolean value 4 years ago
Daniel Martí c0731921c2
rewrite go:linkname directives with garbled names (#200)
If code includes a linkname directive pointing at a name in an imported
package, like:

	//go:linkname localName importedpackage.RemoteName
	func localName()

We should rewrite the comment to replace "RemoteName" with its
obfuscated counterpart, if the package in question was obfuscated and
that name was as well.

We already had some code to handle linkname directives, but only to
ensure that "localName" was never obfuscated. This behavior is kept, to
ensure that the directive applies to the right name. In the future, we
could instead rewrite "localName" in the directive, like we do with
"RemoteName".

Add plenty of tests, too. The linkname directive used to be tested in
imports.txt and syntax.txt, but that was hard to maintain as each file
tested different edge cases.

Now that we have build caching, adding one extra testscript file isn't a
big problem anymoree. Add linkname.txt, which is self-explanatory. The
other two scripts also get a bit less complex.

Fixes #197.
4 years ago
Daniel Martí 2b26183253
reduce the amount of code to handle compiler directives (#199)
First, we don't need the nameSpecialDirectives list as a separate thing.
cgo types aren't obfuscated anymore, so the only item in that list that
made a difference in the tests was go:linkname, which we'll overhaul
soon. For now, keep its code around.

Second, processDetachedDirectives can be replaced by just seven lines.

Third, we don't need to separate build tag directives from the rest of
the detached directives. Their relative order (with other comments) does
not matater.

Fourth and last, ranging over a nil slice is a no-op, so a nil check
around a slice range is unnecessary.

This is some prep work to make the patch to support go:linkname smaller
and easier to review.
4 years ago
Daniel Martí 4f65e6f99c
testdata: avoid messing with the host's mod cache (#198)
It turns out that the modules we include in testdata/mod via
txtar-addmod don't result in the same h1 hash that one gets when using
proxy.golang.org.

As proof:

	$ go clean -modcache && go get -d rsc.io/quote@v1.5.2 && go test -short
	[...]
	--- FAIL: TestScripts/imports (0.06s)
		> garble build -tags buildtag
		go list error: exit status 1: verifying rsc.io/quote@v1.5.2: checksum mismatch
		    downloaded: h1:w5fcysjrx7yqtD/aO+QwRjYZOKnaM9Uh2b40tElTs3Y=
		    go.sum:     h1:3fEykkD9k7lYzXqCYrwGAf7iNhbk4yCjHmKBN9td4L0=

The added comment explains the situation in detail.

For now, simply work around the issue by not sharing GOMODCACHE with the
host.
4 years ago
Daniel Martí c9deff810b
obfuscate fewer std packages (#196)
Previously, we were never obfuscating runtime and its direct
dependencies. Unfortunately, due to linkname, the runtime package is
actually closely related to dozens of other std packages as well.

Until we can obfuscate the runtime and properly support go:linkname
directives, obfuscating fewer std packages is a better outcome than
breaking and not producing any obfuscated code at all.

The added test case is building runtime/pprof, which used to cause
failures:

	# runtime/pprof
	/go/src/runtime/pprof/label.go:27:21: undefined: context.Context
	/go/src/runtime/pprof/label.go:59:21: undefined: context.Context
	/go/src/runtime/pprof/label.go:93:16: undefined: context.Context
	/go/src/runtime/pprof/label.go:101:20: undefined: context.Context

The net package was also very close to obfuscating properly thanks to
this change, so its test is now run as well. The only other remaining
fix was to not obfuscate fields on cgo types, since those aren't
obfuscated at the moment.

The map is pretty long, but it's only a temporary solution and the
command to obtain the list again is included. Never obfuscating the
entire std library is also an option, but it's a bit unnecessary.

Fixes #134.
4 years ago
Andrew LeFevre 6857aa1426
fix 2 small bugs in import obfuscation (#195)
The first bug fixed is not garbling package names that don't contain any code. For example, given the import path "github.com/foo/bar", "github.com" was treated as a package name that should be garbled, which doesn't make sense.

The other bug was incorrectly matching private package names inside import paths. Before, if "internal" was an imported package matched by GOPRIVATE, but "internal/foo" was not, any instance of "internal/foo" would still be garbled as "<garbled>/foo", which is incorrect.
4 years ago
lu4p cf290b8e6d
Share data between processes via a shared file. (#192)
Previously garble heavily used env vars to share data between processes.
This also makes it easy to share complex data between processes.

The complexity of main.go is considerably reduced.
4 years ago
Daniel Martí dfa622fe50
simplify globals, split hash.go (#191)
The previous globals worked, but were unnecessarily complex. For
example, we passed the fromPath variable around, but it's really a
static global, since we only compile or link a single package in each Go
process. Use such global variables instead of passing them around, which
currently include the package's import path, its build ID, and its
import config path.

Also split all the hashing and build ID code into hash.go, since that's
a relatively well contained 200 lines of code that doesn't need to make
main.go any bigger. We also split the code to alter Go's own version to
a separate function, so that it can be moved out of main.go as well.
4 years ago
Andrew LeFevre 8c03afee95
Use latest Binject/debug version to support importmap directives, fixes #146 (#189)
* Use latest Binject/debug version to support importmap directives in the importcfg file

* Uncomment line in goprivate testscript to test ImportMap

* Fixed issue where a package in specified in importmap would be hashed differently in a package that imported it, due to the mapping of import paths.

Also commented out the 'net' import in the goprivate testscript (again) due to cgo compile errors
4 years ago
Daniel Martí 3e7416ee9e
add test case for ImportMap support (#186)
We also update the "original types importer" to support ImportMap.

The test now gets further along, no longer getting stuck on "path not
found in listed packages". Instead, we get stuck on:

	error parsing importcfg: <...>/importcfg:2: unknown directive "importmap"

This bug has been filed at https://github.com/Binject/debug/issues/17.
Until it's fixed, we can't really proceed on #146, so the net import in
the test file (which triggers this case) is commented out for now.

Updates #146.
4 years ago
Daniel Martí 1336711c9c
CONTRIBUTING: include some basic terminology (#188)
Fixes #132.
4 years ago
lu4p e35f19ab1b
Add a Contributing section to the README (#187)
Fixes #185
4 years ago
Daniel Martí 39372a8c9b testdata: don't let tests rely on rewriting mod files
In Go 1.15, if a dependency is required but not listed in go.mod/go.sum,
it's resolved and added automatically.

This is changing in 1.16. From that release, one will have to explicitly
update the mod files via 'go mod tidy' or 'go get'.

To get ahead of the curve, start using -mod=readonly to get the same
behavior in 1.15, and fix all existing tests.

The only tests that failed were imports.txt and syntax.txt, the only
ones to require other modules. But since we're here, let's add the 'go'
line to all go.mod files as well.
4 years ago
Daniel Martí 4e79bfc01a
warn when a public package imports a private package (#182)
That is, a package that is built without obfuscation imports an
obfuscated package. This will result in confusing compilation error
messages, because the importer can't find the exported names from the
imported package by their non-obfuscated names:

	> ! garble build ./importer
	[stderr]
	# test/main/importer
	importer/importer.go:5:9: undefined: imported.Name
	exit status 2

Instead, detect this bad input case and provide a nice error:

	public package "test/main/importer" can't depend on obfuscated package "test/main/imported" (matched via GOPRIVATE="test/main/imported")

For now, this is by design. It also makes little sense for a public
package to import an obfuscated package in general, because the public
package would have to leak details about the private package's API and
behavior.

While at it, fix a quirk where we thought the unsafe package could be
private. It can't be, because the runtime package is always public and
it imports the runtime package:

	public package "internal/bytealg" can't depend on obfuscated package "unsafe" (matched via GOPRIVATE="*")

Instead of trying to obfuscate "unsafe" and doing nothing, simply add it
to the neverPrivate list, which is also a better name than
"privateBlacklist" (for #169).

Fixes #164.

Co-authored-by: lu4p <lu4p@pm.me>
4 years ago
Andrew LeFevre 523cc4454f
Hash identical package names from different package paths differently (#172) 4 years ago
Nick 43163c2e9b Remove the `usesUnsafe` global variable as it's unused
I've tested the code on unsafe code bases as well, I truly believe that
this variable is not necessary/used.
4 years ago
Nick d4eee0c9bc Replaced asthelper.Ident with ast.NewIdent
No point in having around a helper method that has been implemented for
us by `go/ast`
4 years ago
Daniel Martí 07fd9d5beb introduce a receiver type to transform a Go package
Means that we no longer have to pass a dozen parameters around, mainly
to transformGo. We can also start documenting what each of the fields
actually does, and group them better.

While at it, pkgPath and pkgScope can both be replaced by a
*types.Package, since they're both accessible via trivially cheap
methods.
4 years ago
Andrew LeFevre bca460e36e
Print interfaces/pointers when -tiny is used (#170)
fixes #167
4 years ago
Daniel Martí 7ad246c6fe
testdata: make tiny.txt simpler and faster (#168)
By avoiding the fmt import, we save some work: 'go test -run Script/tiny'
goes down from 0.8s to 0.5s even with a warm build cache.

Since the output changes between runs, we use stderr grep lines instead
of cmp. This way we can also check that the "oh noes" panic is entirely
hidden in the tiny mode.
4 years ago
Daniel Martí 95501f0fcd
testdata: avoid unnecessary deps in init.txt (#166)
We can use println instead of fmt.Println. Similarly, we can avoid
strings.Join by just appending bytes to a []byte.

This is less important now that we have build caching, but it still
helps to do less work overall and link smaller binaries.

Reduces 'go test -run Script/init' from 0.5s to 0.3s on my laptop.

Also, properly format the Go in that file, since the space indentation
wasn't noticed during code review. We might want to enforce gofmt in Go
files within txtar files if this keeps happening.
4 years ago
Andrew LeFevre 6cf1eb6d49
keep init funcs in original order (#165) 4 years ago
Andrew LeFevre 1fc990dcf8
Fix bug where structs would get garbled in some packages but not in others (#161)
* fix bug where structs would get garbled in some packages but not in others

* only check if struct/field was not defined in current package

* fix a related bug when two objects share the same name in the same package and one is garbled but the other one is not

* renamed parameter for clarity
4 years ago
Andrew LeFevre 047aa254e2
properly remove all filenames when -tiny is passed (#160)
* properly remove all filenames when -tiny is passed

* document filename symbol removal
4 years ago
Andrew LeFevre 0e0a9fc594
Allow struct fields to be garbled, fixes #48 (#159)
* Allow struct fields to be garbled, fixes #48

* fix syntax test script

* simplified code according to review
4 years ago
pagran 803c1d9439
Store obfuscated sources in object files (#158)
Now the flag "-debugdir" does not trigger a full recompilation.
Obfuscated source files are saved to object files and are extracted during linking.
4 years ago
Daniel Martí 29378787e2
CI: comment out test-gotip for now (#157)
Since it's been failing for weeks, it's practically useless for now.
Even with continue-on-error, the failures still look scary at first
glance.

We can re-enable this job once we fix master.
4 years ago
Daniel Martí b823b07443 testdata: avoid 'go build' with -short in literals.txt
Use a static main.stderr file, like in the other tests. This means we
don't need to always start the test with a 'go build', and the output is
also obvious by just reading the txtar file.

We can also move generate-literals to a later stage, so that 'go test
-short' needs to do even less work.

'go test -short -run Script/literals' drops from ~0.4s to ~0.2s on my
laptop.

Finally, make the printing of byte lists not use trailing spaces, so
that the txtar file itself doesn't have trailing whitespace in its lines
either.

Fixes #103.
4 years ago
Daniel Martí 1e19d136c7 testdata: make syntax.txt pass when offline
The test intended to use an extra module to be obfuscated, rsc.io/quote,
which we were bundling in the local proxy as well. Unfortunately, the
use of GOPRIVATE also meant that we did not actually fetch the module
from the proxy, and we would instead do a full roundtrip to the internet
to "git clone" the actual upstream repository.

To prevent that roundtrip, instead use a locally replaced module. This
fits the syntax.txt test too, since it's one more edge case that we want
to make sure works well with garble. Since rsc.io/quote is used in
another test, simply make up our own tiny module.

Reduces a 'go test -run Syntax/syntax' run with warm cache from ~5s to
~0.5s, thanks to removing the multiple roundtrips. A warm 'go test' run
still sits at ~6s, since we still need that much CPU time in total.

While at it, fix a staticcheck warning and fix inconsistent indentation
in a couple of tests.
4 years ago
Daniel Martí 2a0ac434fb
initial support for build caching (#142)
As per the discussion in https://github.com/golang/go/issues/41145, it
turns out that we don't need special support for build caching in
-toolexec. We can simply modify the behavior of "[...]/compile -V=full"
and "[...]/link -V=full" so that they include garble's own version and
options in the printed build ID.

The part of the build ID that matters is the last, since it's the
"content ID" which is used to work out whether there is a need to redo
the action (build) or not. Since cmd/go parses the last word in the
output as "buildID=...", we simply add "+garble buildID=_/_/_/${hash}".
The slashes let us imitate a full binary build ID, but we assume that
the other components such as the action ID are not necessary, since the
only reader here is cmd/go and it only consumes the content ID.

The reported content ID includes the tool's original content ID,
garble's own content ID from the built binary, and the garble options
which modify how we obfuscate code. If any of the three changes, we
should use a different build cache key. GOPRIVATE also affects caching,
since a different GOPRIVATE value means that we might have to garble a
different set of packages.

Include tests, which mainly check that 'garble build -v' prints package
lines when we expect to always need to rebuild packages, and that it
prints nothing when we should be reusing the build cache even when the
built binary is missing.

After this change, 'go test' on Go 1.15.2 stabilizes at about 8s on my
machine, whereas it used to be at around 25s before.
4 years ago
Daniel Martí 859221a950 make import path obfuscation work with the build cache
What obfuscateImports did was valid, but unfortunately made the build
cache redo work. This is because we were modifying object files in-place
in the build cache, meaning that the Go tool would think it had to
re-compile those packages.

Instead, write the modified object files in a temporary directory, and
leave the input object files untouched. We require a bit of extra code
to keep track of this and adjust the link argument as well as its
importcfg file.

The function of obfuscateImports, as well as the reasoning above, is now
summarized in its godoc as well.

This should be the last change in preparation for proper build caching
support. Rebasing the build caching branch on this commit finally makes
caching work reliably every single time.
4 years ago
pagran ea4a01df87
More correct comments transformation (#152)
More correct comments transformation was implemented.

Added processing of //go:linkname localname [importpath.name] directive, now localname is not renamed. This is safe and does not cause a name disclosure because the functions marked //linkname do not have a name in the resulting binary.

Added cgo directives support

Fixed filename leak protection for cgo

Part of #149
4 years ago
pagran 991fbb042b
avoid potential short name collisions
Fix for bug when a conflict occurred between generated short names
and local variables/functions/types/structs.

The already existing names are collected and if the generated short name
already exists, the package counter is increased until a free name is found.

Part of #149.
4 years ago
pagran 434df0476d
fixed comments cleaning
Added cleanup of the Comment field.
In some cases, the appearance of a comment in a random place
may break the compilation (e.g. cgo and runtime package).

This is safe because the Comment field cannot contain any directives.

Part of #149.
4 years ago
Daniel Martí 88450a2cbc
update Binject/debug dependency to get its license file (#148)
See https://github.com/Binject/debug/issues/12.

Also update x/tools, while at it.
4 years ago
Daniel Martí 3970bb98cc clean up global buildInfo a bit, fix up godocs
The struct type for buildInfo doesn't need to be named. Plus, the
"packageInfo" name was actually pretty misleading, because buildInfo
contains data from many packages.

Add an importCfg field, so that we don't need to fetch the flag value
many times.

Simplify reading the importCfg file; we used to also write to it, but
that's no longer the case, so we can just use ioutil.ReadFile.

Finally, give the function that fills buildInfo a better name, a godoc,
and fix the origTypesConfig godoc.

We also add a TODO to reuse goobj.ParseImportCfg in the future.
4 years ago
pagran 406036d433
rewrite private name map storage to support build caching
We now store how we obfuscated unexported names in the object file
itself, not a separate file. This means that the data can survive in the
build cache, whereas the separate file was being lost. Luckily, we can
just add an extra header to the archive, and other programs like the Go
linker will just ignore it.
4 years ago
pagran 5c6fa4575f
Remove unused constant and fix magic number (#143)
Removed PosMax constant as it is no longer needed after optimization (b3f04e5) of line obfuscation.
Replaced the magic number with PosMin
4 years ago
Daniel Martí c3bee46a26 testdata: use the debugdir flag less often
In tiny.txt, we already check line numbers via stderr, so there's no
need to do that via -debugdir.

In syntax.txt, we only really care about what names remain in the
binary, not the names which remain in the source but don't affect the
binary.

These changes are important because -debugdir adds a non-trivial amount
of work, which will impede build caching once that feature lands. We
will likely make -debugdir support build caching eventually, but for
now, this preliminary change will make 'go test' much faster with build
caching.

And of course, the tests get simpler, which is nice.
4 years ago
pagran 00c1d5b11d
add test for Go version checking (#140)
Add tests for Go version checking

Fix panic if go version has invalid format

Fixes: #121
Co-authored-by: Daniel Martí <mvdan@mvdan.cc>
4 years ago