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
|
|
|
# Ensure that "does not match any packages" works.
|
deprecate using GOPRIVATE in favor of GOGARBLE (#427)
Piggybacking off of GOPRIVATE is great for a number of reasons:
* People tend to obfuscate private code, whose package paths will
generally be in GOPRIVATE already
* Its meaning and syntax are well understood
* It allows all the flexibility we need without adding our own env var
or config option
However, using GOPRIVATE directly has one main drawback.
It's fairly common to also want to obfuscate public dependencies,
to make the code in private packages even harder to follow.
However, using "GOPRIVATE=*" will result in two main downsides:
* GONOPROXY defaults to GOPRIVATE, so the proxy would be entirely disabled.
Downloading modules, such as when adding or updating dependencies,
or when the local cache is cold, can be less reliable.
* GONOSUMDB defaults to GOPRIVATE, so the sumdb would be entirely disabled.
Adding entries to go.sum, such as when adding or updating dependencies,
can be less secure.
We will continue to consume GOPRIVATE as a fallback,
but we now expect users to set GOGARBLE instead.
The new logic is documented in the README.
While here, rewrite some uses of "private" with "to obfuscate",
to make the code easier to follow and harder to misunderstand.
Fixes #276.
3 years ago
|
|
|
env GOGARBLE=match-absolutely/nothing
|
|
|
|
|
! exec garble build -o=main$exe ./standalone
|
deprecate using GOPRIVATE in favor of GOGARBLE (#427)
Piggybacking off of GOPRIVATE is great for a number of reasons:
* People tend to obfuscate private code, whose package paths will
generally be in GOPRIVATE already
* Its meaning and syntax are well understood
* It allows all the flexibility we need without adding our own env var
or config option
However, using GOPRIVATE directly has one main drawback.
It's fairly common to also want to obfuscate public dependencies,
to make the code in private packages even harder to follow.
However, using "GOPRIVATE=*" will result in two main downsides:
* GONOPROXY defaults to GOPRIVATE, so the proxy would be entirely disabled.
Downloading modules, such as when adding or updating dependencies,
or when the local cache is cold, can be less reliable.
* GONOSUMDB defaults to GOPRIVATE, so the sumdb would be entirely disabled.
Adding entries to go.sum, such as when adding or updating dependencies,
can be less secure.
We will continue to consume GOPRIVATE as a fallback,
but we now expect users to set GOGARBLE instead.
The new logic is documented in the README.
While here, rewrite some uses of "private" with "to obfuscate",
to make the code easier to follow and harder to misunderstand.
Fixes #276.
3 years ago
|
|
|
stderr '^GOGARBLE="match-absolutely/nothing" does not match any packages to be built$'
|
|
|
|
|
|
|
|
|
|
# A build where just some packages are obfuscated.
|
deprecate using GOPRIVATE in favor of GOGARBLE (#427)
Piggybacking off of GOPRIVATE is great for a number of reasons:
* People tend to obfuscate private code, whose package paths will
generally be in GOPRIVATE already
* Its meaning and syntax are well understood
* It allows all the flexibility we need without adding our own env var
or config option
However, using GOPRIVATE directly has one main drawback.
It's fairly common to also want to obfuscate public dependencies,
to make the code in private packages even harder to follow.
However, using "GOPRIVATE=*" will result in two main downsides:
* GONOPROXY defaults to GOPRIVATE, so the proxy would be entirely disabled.
Downloading modules, such as when adding or updating dependencies,
or when the local cache is cold, can be less reliable.
* GONOSUMDB defaults to GOPRIVATE, so the sumdb would be entirely disabled.
Adding entries to go.sum, such as when adding or updating dependencies,
can be less secure.
We will continue to consume GOPRIVATE as a fallback,
but we now expect users to set GOGARBLE instead.
The new logic is documented in the README.
While here, rewrite some uses of "private" with "to obfuscate",
to make the code easier to follow and harder to misunderstand.
Fixes #276.
3 years ago
|
|
|
env GOGARBLE=test/main/imported
|
|
|
|
|
exec garble -literals build -o=main$exe ./importer
|
|
|
|
|
|
|
|
|
|
! binsubstr main$exe 'some long string to obfuscate'
|
|
|
|
|
binsubstr main$exe 'some long string to not obfuscate'
|
|
|
|
|
|
keep importmap entries in the right direction
For packages that we alter, we parse and modify the importcfg file.
Parsing is necessary so we can locate obfuscated object files,
which we use to remember what identifiers were obfuscated.
Modifying the files is necessary when we obfuscate import paths,
and those import paths have entries in an importcfg file.
However, we made one crucial mistake when writing the code.
When handling importmap entries such as:
importmap golang.org/x/net/idna=vendor/golang.org/x/net/idna
we would name the two sides beforePath and afterPath, respectively.
They were added to importMap with afterPath as the key,
but when we iterated over the map to write a modified importcfg file,
we would then assume the key is beforepath.
All in all, we would end up writing the opposite direction:
importmap vendor/golang.org/x/net/idna=golang.org/x/net/idna
This would ultimately result in the importmap never being useful,
and some rather confusing error messages such as:
cannot find package golang.org/x/net/idna (using -importcfg)
Add a test case that reproduces this error,
and fix the code so it always uses beforePath as the key.
Note that we were also updating importCfgEntries with such entries.
I could not reproduce any failure when just removing that code,
nor could I explain why it was added there in the first place.
As such, remove that bit of code as well.
Finally, a reasonable question might be why we never noticed the bug.
In practice, such "importmap"s, represented as ImportMap by "go list",
only currently appear for packages vendored into the standard library.
Until very recently, we didn't support obfuscating most of std,
so we would usually not alter the affected importcfg files.
Now that we do parse and modify them, the bug surfaced.
Fixes #408.
3 years ago
|
|
|
# Obfuscated packages which import non-obfuscated std packages.
|
|
|
|
|
# Some of the imported std packages use "import maps" due to vendoring,
|
|
|
|
|
# and a past bug made this case fail for "garble build".
|
deprecate using GOPRIVATE in favor of GOGARBLE (#427)
Piggybacking off of GOPRIVATE is great for a number of reasons:
* People tend to obfuscate private code, whose package paths will
generally be in GOPRIVATE already
* Its meaning and syntax are well understood
* It allows all the flexibility we need without adding our own env var
or config option
However, using GOPRIVATE directly has one main drawback.
It's fairly common to also want to obfuscate public dependencies,
to make the code in private packages even harder to follow.
However, using "GOPRIVATE=*" will result in two main downsides:
* GONOPROXY defaults to GOPRIVATE, so the proxy would be entirely disabled.
Downloading modules, such as when adding or updating dependencies,
or when the local cache is cold, can be less reliable.
* GONOSUMDB defaults to GOPRIVATE, so the sumdb would be entirely disabled.
Adding entries to go.sum, such as when adding or updating dependencies,
can be less secure.
We will continue to consume GOPRIVATE as a fallback,
but we now expect users to set GOGARBLE instead.
The new logic is documented in the README.
While here, rewrite some uses of "private" with "to obfuscate",
to make the code easier to follow and harder to misunderstand.
Fixes #276.
3 years ago
|
|
|
env GOGARBLE=test/main
|
|
|
|
|
exec garble build -o=main$exe ./stdimporter
|
keep importmap entries in the right direction
For packages that we alter, we parse and modify the importcfg file.
Parsing is necessary so we can locate obfuscated object files,
which we use to remember what identifiers were obfuscated.
Modifying the files is necessary when we obfuscate import paths,
and those import paths have entries in an importcfg file.
However, we made one crucial mistake when writing the code.
When handling importmap entries such as:
importmap golang.org/x/net/idna=vendor/golang.org/x/net/idna
we would name the two sides beforePath and afterPath, respectively.
They were added to importMap with afterPath as the key,
but when we iterated over the map to write a modified importcfg file,
we would then assume the key is beforepath.
All in all, we would end up writing the opposite direction:
importmap vendor/golang.org/x/net/idna=golang.org/x/net/idna
This would ultimately result in the importmap never being useful,
and some rather confusing error messages such as:
cannot find package golang.org/x/net/idna (using -importcfg)
Add a test case that reproduces this error,
and fix the code so it always uses beforePath as the key.
Note that we were also updating importCfgEntries with such entries.
I could not reproduce any failure when just removing that code,
nor could I explain why it was added there in the first place.
As such, remove that bit of code as well.
Finally, a reasonable question might be why we never noticed the bug.
In practice, such "importmap"s, represented as ImportMap by "go list",
only currently appear for packages vendored into the standard library.
Until very recently, we didn't support obfuscating most of std,
so we would usually not alter the affected importcfg files.
Now that we do parse and modify them, the bug surfaced.
Fixes #408.
3 years ago
|
|
|
|
|
|
|
|
[short] stop # rebuilding std is slow
|
|
|
|
|
|
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
|
|
|
# Go back to the default of obfuscating all packages.
|
deprecate using GOPRIVATE in favor of GOGARBLE (#427)
Piggybacking off of GOPRIVATE is great for a number of reasons:
* People tend to obfuscate private code, whose package paths will
generally be in GOPRIVATE already
* Its meaning and syntax are well understood
* It allows all the flexibility we need without adding our own env var
or config option
However, using GOPRIVATE directly has one main drawback.
It's fairly common to also want to obfuscate public dependencies,
to make the code in private packages even harder to follow.
However, using "GOPRIVATE=*" will result in two main downsides:
* GONOPROXY defaults to GOPRIVATE, so the proxy would be entirely disabled.
Downloading modules, such as when adding or updating dependencies,
or when the local cache is cold, can be less reliable.
* GONOSUMDB defaults to GOPRIVATE, so the sumdb would be entirely disabled.
Adding entries to go.sum, such as when adding or updating dependencies,
can be less secure.
We will continue to consume GOPRIVATE as a fallback,
but we now expect users to set GOGARBLE instead.
The new logic is documented in the README.
While here, rewrite some uses of "private" with "to obfuscate",
to make the code easier to follow and harder to misunderstand.
Fixes #276.
3 years ago
|
|
|
env GOGARBLE='*'
|
|
|
|
|
|
|
|
|
|
# Try garbling all of std, given some std packages.
|
|
|
|
|
# No need for a main package here; building the std packages directly works the
|
|
|
|
|
# same, and is faster as we don't need to link a binary.
|
|
|
|
|
# This used to cause multiple errors, mainly since std vendors some external
|
|
|
|
|
# packages so we must properly support ImportMap.
|
|
|
|
|
# Plus, some packages like net make heavy use of complex features like Cgo.
|
|
|
|
|
# Note that we won't obfuscate a few std packages just yet, mainly those around runtime.
|
|
|
|
|
exec garble build std
|
|
|
|
|
! stderr . # no warnings
|
|
|
|
|
|
|
|
|
|
# Link a binary importing net/http, which will catch whether or not we
|
|
|
|
|
# support ImportMap when linking.
|
|
|
|
|
# Also ensure we are obfuscating low-level std packages.
|
|
|
|
|
exec garble build -o=main$exe ./stdimporter
|
|
|
|
|
! stderr . # no warnings
|
|
|
|
|
! binsubstr main$exe 'http.ListenAndServe' 'debug.WriteHeapDump' 'time.Now' 'syscall.Listen'
|
|
|
|
|
|
|
|
|
|
# Ensure that the embedded runtime.GOROOT and runtime.Version are unset.
|
|
|
|
|
# Note that testscript sets GOROOT explicitly, which we don't want to use.
|
|
|
|
|
env GOROOT=
|
|
|
|
|
exec ./main$exe
|
|
|
|
|
cmp stdout stdimporter.stdout
|
|
|
|
|
|
|
|
|
|
# The same low-level std packages appear in plain sight in regular builds.
|
|
|
|
|
go build -o=main_regular$exe ./stdimporter
|
|
|
|
|
binsubstr main_regular$exe 'http.ListenAndServe' 'debug.WriteHeapDump' 'time.Now' 'syscall.Listen'
|
|
|
|
|
|
ensure the runtime is built in a reproducible way
We went to great lengths to ensure garble builds are reproducible.
This includes how the tool itself works,
as its behavior should be the same given the same inputs.
However, we made one crucial mistake with the runtime package.
It has go:linkname directives pointing at other packages,
and some of those pointed packages aren't its dependencies.
Imagine two scenarios where garble builds the runtime package:
1) We run "garble build runtime". The way we handle linkname directives
calls listPackage on the target package, to obfuscate the target's
import path and object name. However, since we only obtained build
info of runtime and its deps, calls for some linknames such as
listPackage("sync/atomic") will fail. The linkname directive will
leave its target untouched.
2) We run "garble build std". Unlike the first scenario, all listPackage
calls issued by runtime's linkname directives will succeed, so its
linkname directive targets will be obfuscated.
At best, this can result in inconsistent builds, depending on how the
runtime package was built. At worst, the mismatching object names can
result in errors at link time, if the target packages are actually used.
The modified test reproduces the worst case scenario reliably,
when the fix is reverted:
> env GOCACHE=${WORK}/gocache-empty
> garble build -a runtime
> garble build -o=out_rebuild ./stdimporter
[stderr]
# test/main/stdimporter
JZzQivnl.NtQJu0H3: relocation target JZzQivnl.iioHinYT not defined
JZzQivnl.NtQJu0H3.func9: relocation target JZzQivnl.yz5z0NaH not defined
JZzQivnl.(*ypvqhKiQ).String: relocation target JZzQivnl.eVciBQeI not defined
JZzQivnl.(*ypvqhKiQ).PkgPath: relocation target JZzQivnl.eVciBQeI not defined
[...]
The fix consists of two steps. First, if we're building the runtime and
listPackage fails on a package, that means we ran into scenario 1 above.
To avoid the inconsistency, we fill ListedPackages with "go list [...] std".
This means we'll always build runtime as described in scenario 2 above.
Second, when building packages other than the runtime,
we only allow listPackage to succeed if we're listing a dependency of
the current package.
This ensures we won't run into similar reproducibility bugs in the future.
Finally, re-enable test-gotip on CI since this was the last test flake.
3 years ago
|
|
|
# Also check that a full rebuild is reproducible, via a new GOCACHE.
|
avoid reproducibility issues with full rebuilds
We were using temporary filenames for modified Go and assembly files.
For example, an obfuscated "encoding/json/encode.go" would end up as:
/tmp/garble-shared123/encode.go.456.go
where "123" and "456" are random numbers, usually longer.
This was usually fine for two reasons:
1) We would add "/tmp/garble-shared123/" to -trimpath, so the temporary
directory and its random number would be invisible.
2) We would add "//line" directives to the source files, replacing
the filename with obfuscated versions excluding any random number.
Unfortunately, this broke in multiple ways. Most notably, assembly files
do not have any line directives, and it's not clear that there's any
support for them. So the random number in their basename could end up in
the binary, breaking reproducibility.
Another issue is that the -trimpath addition described above was only
done for cmd/compile, not cmd/asm, so assembly filenames included the
randomized temporary directory.
To fix the issues above, the same "encoding/json/encode.go" would now
end up as:
/tmp/garble-shared123/encoding/json/encode.go
Such a path is still unique even though the "456" random number is gone,
as import paths are unique within a single build.
This fixes issues with the base name of each file, so we no longer rely
on line directives as the only way to remove the second original random
number.
We still rely on -trimpath to get rid of the temporary directory in
filenames. To fix its problem with assembly files, also amend the
-trimpath flag when running the assembler tool.
Finally, add a test that reproducible builds still work when a full
rebuild is done. We choose goprivate.txt for such a test as its
stdimporter package imports a number of std packages, including uses of
assembly and cgo.
For the time being, we don't use such a "full rebuild" reproducibility
test in other test scripts, as this step is expensive, rebuilding many
packages from scratch.
This issue went unnoticed for over a year because such random numbers
"123" and "456" were created when a package was obfuscated, and that
only happened once per package version as long as the build cache was
kept intact.
When clearing the build cache, or forcing a rebuild with -a, one gets
new random numbers, and thus a different binary resulting from the same
build input. That's not something that most users would do regularly,
and our tests did not cover that edge case either, until now.
Fixes #328.
4 years ago
|
|
|
# This is slow, but necessary to uncover bugs hidden by the build cache.
|
ensure the runtime is built in a reproducible way
We went to great lengths to ensure garble builds are reproducible.
This includes how the tool itself works,
as its behavior should be the same given the same inputs.
However, we made one crucial mistake with the runtime package.
It has go:linkname directives pointing at other packages,
and some of those pointed packages aren't its dependencies.
Imagine two scenarios where garble builds the runtime package:
1) We run "garble build runtime". The way we handle linkname directives
calls listPackage on the target package, to obfuscate the target's
import path and object name. However, since we only obtained build
info of runtime and its deps, calls for some linknames such as
listPackage("sync/atomic") will fail. The linkname directive will
leave its target untouched.
2) We run "garble build std". Unlike the first scenario, all listPackage
calls issued by runtime's linkname directives will succeed, so its
linkname directive targets will be obfuscated.
At best, this can result in inconsistent builds, depending on how the
runtime package was built. At worst, the mismatching object names can
result in errors at link time, if the target packages are actually used.
The modified test reproduces the worst case scenario reliably,
when the fix is reverted:
> env GOCACHE=${WORK}/gocache-empty
> garble build -a runtime
> garble build -o=out_rebuild ./stdimporter
[stderr]
# test/main/stdimporter
JZzQivnl.NtQJu0H3: relocation target JZzQivnl.iioHinYT not defined
JZzQivnl.NtQJu0H3.func9: relocation target JZzQivnl.yz5z0NaH not defined
JZzQivnl.(*ypvqhKiQ).String: relocation target JZzQivnl.eVciBQeI not defined
JZzQivnl.(*ypvqhKiQ).PkgPath: relocation target JZzQivnl.eVciBQeI not defined
[...]
The fix consists of two steps. First, if we're building the runtime and
listPackage fails on a package, that means we ran into scenario 1 above.
To avoid the inconsistency, we fill ListedPackages with "go list [...] std".
This means we'll always build runtime as described in scenario 2 above.
Second, when building packages other than the runtime,
we only allow listPackage to succeed if we're listing a dependency of
the current package.
This ensures we won't run into similar reproducibility bugs in the future.
Finally, re-enable test-gotip on CI since this was the last test flake.
3 years ago
|
|
|
# We also forcibly rebuild runtime on its own, given it used to be non-reproducible
|
|
|
|
|
# due to its use of linknames pointing at std packages it doesn't depend upon.
|
|
|
|
|
[darwin] skip 'see https://github.com/burrowers/garble/issues/609'
|
ensure the runtime is built in a reproducible way
We went to great lengths to ensure garble builds are reproducible.
This includes how the tool itself works,
as its behavior should be the same given the same inputs.
However, we made one crucial mistake with the runtime package.
It has go:linkname directives pointing at other packages,
and some of those pointed packages aren't its dependencies.
Imagine two scenarios where garble builds the runtime package:
1) We run "garble build runtime". The way we handle linkname directives
calls listPackage on the target package, to obfuscate the target's
import path and object name. However, since we only obtained build
info of runtime and its deps, calls for some linknames such as
listPackage("sync/atomic") will fail. The linkname directive will
leave its target untouched.
2) We run "garble build std". Unlike the first scenario, all listPackage
calls issued by runtime's linkname directives will succeed, so its
linkname directive targets will be obfuscated.
At best, this can result in inconsistent builds, depending on how the
runtime package was built. At worst, the mismatching object names can
result in errors at link time, if the target packages are actually used.
The modified test reproduces the worst case scenario reliably,
when the fix is reverted:
> env GOCACHE=${WORK}/gocache-empty
> garble build -a runtime
> garble build -o=out_rebuild ./stdimporter
[stderr]
# test/main/stdimporter
JZzQivnl.NtQJu0H3: relocation target JZzQivnl.iioHinYT not defined
JZzQivnl.NtQJu0H3.func9: relocation target JZzQivnl.yz5z0NaH not defined
JZzQivnl.(*ypvqhKiQ).String: relocation target JZzQivnl.eVciBQeI not defined
JZzQivnl.(*ypvqhKiQ).PkgPath: relocation target JZzQivnl.eVciBQeI not defined
[...]
The fix consists of two steps. First, if we're building the runtime and
listPackage fails on a package, that means we ran into scenario 1 above.
To avoid the inconsistency, we fill ListedPackages with "go list [...] std".
This means we'll always build runtime as described in scenario 2 above.
Second, when building packages other than the runtime,
we only allow listPackage to succeed if we're listing a dependency of
the current package.
This ensures we won't run into similar reproducibility bugs in the future.
Finally, re-enable test-gotip on CI since this was the last test flake.
3 years ago
|
|
|
env GOCACHE=${WORK}/gocache-empty
|
|
|
|
|
exec garble build -a runtime
|
|
|
|
|
exec garble build -o=main_rebuild$exe ./stdimporter
|
|
|
|
|
bincmp main_rebuild$exe main$exe
|
|
|
|
|
-- go.mod --
|
|
|
|
|
module test/main
|
|
|
|
|
|
|
|
|
|
go 1.23
|
|
|
|
|
-- standalone/main.go --
|
|
|
|
|
package main
|
|
|
|
|
|
|
|
|
|
func main() {}
|
|
|
|
|
-- importer/importer.go --
|
|
|
|
|
package main
|
|
|
|
|
|
|
|
|
|
import "test/main/imported"
|
|
|
|
|
|
|
|
|
|
func main() {
|
|
|
|
|
println(imported.LongString)
|
|
|
|
|
println("some long string to not obfuscate")
|
|
|
|
|
}
|
|
|
|
|
-- imported/imported.go --
|
|
|
|
|
package imported
|
|
|
|
|
|
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var LongString = "some long string to obfuscate"
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-- stdimporter/main.go --
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package main
|
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|
|
|
only list missing packages when obfuscating the runtime
We were listing all of std, which certainly worked,
but was quite slow at over 200 packages.
In practice, we can only be missing up to 20-30 packages.
It was a good change as it fixed a severe bug,
but it also introduced a fairly noticeable slow-down.
The numbers are clear; this change shaves off multiple seconds when
obfuscating the runtime with a cold cache:
name old time/op new time/op delta
Build/NoCache-16 5.06s ± 1% 1.94s ± 1% -61.64% (p=0.008 n=5+5)
name old bin-B new bin-B delta
Build/NoCache-16 6.70M ± 0% 6.71M ± 0% +0.05% (p=0.008 n=5+5)
name old sys-time/op new sys-time/op delta
Build/NoCache-16 13.4s ± 2% 5.0s ± 2% -62.45% (p=0.008 n=5+5)
name old user-time/op new user-time/op delta
Build/NoCache-16 60.6s ± 1% 19.8s ± 1% -67.34% (p=0.008 n=5+5)
Since we only want to call "go list" one extra time,
instead of once for every package we find out we're missing,
we want to know what packages we could be missing in advance.
Resurrect a smarter version of the runtime-related script.
Finally, remove the runtime-related.txt test script,
as it has now been superseeded by the sanity checks in listPackage.
That is, obfuscating the runtime package will now panic if we are
missing any necessary package information.
To double check that we get the runtime's linkname edge case right,
make gogarble.txt use runtime/debug.WriteHeapDump,
which is implemented via a direct runtime linkname.
This ensures we don't lose test coverage from runtime-related.txt.
3 years ago
|
|
|
import (
|
|
|
|
|
"fmt"
|
only list missing packages when obfuscating the runtime
We were listing all of std, which certainly worked,
but was quite slow at over 200 packages.
In practice, we can only be missing up to 20-30 packages.
It was a good change as it fixed a severe bug,
but it also introduced a fairly noticeable slow-down.
The numbers are clear; this change shaves off multiple seconds when
obfuscating the runtime with a cold cache:
name old time/op new time/op delta
Build/NoCache-16 5.06s ± 1% 1.94s ± 1% -61.64% (p=0.008 n=5+5)
name old bin-B new bin-B delta
Build/NoCache-16 6.70M ± 0% 6.71M ± 0% +0.05% (p=0.008 n=5+5)
name old sys-time/op new sys-time/op delta
Build/NoCache-16 13.4s ± 2% 5.0s ± 2% -62.45% (p=0.008 n=5+5)
name old user-time/op new user-time/op delta
Build/NoCache-16 60.6s ± 1% 19.8s ± 1% -67.34% (p=0.008 n=5+5)
Since we only want to call "go list" one extra time,
instead of once for every package we find out we're missing,
we want to know what packages we could be missing in advance.
Resurrect a smarter version of the runtime-related script.
Finally, remove the runtime-related.txt test script,
as it has now been superseeded by the sanity checks in listPackage.
That is, obfuscating the runtime package will now panic if we are
missing any necessary package information.
To double check that we get the runtime's linkname edge case right,
make gogarble.txt use runtime/debug.WriteHeapDump,
which is implemented via a direct runtime linkname.
This ensures we don't lose test coverage from runtime-related.txt.
3 years ago
|
|
|
"net/http"
|
|
|
|
|
"os"
|
|
|
|
|
"runtime"
|
only list missing packages when obfuscating the runtime
We were listing all of std, which certainly worked,
but was quite slow at over 200 packages.
In practice, we can only be missing up to 20-30 packages.
It was a good change as it fixed a severe bug,
but it also introduced a fairly noticeable slow-down.
The numbers are clear; this change shaves off multiple seconds when
obfuscating the runtime with a cold cache:
name old time/op new time/op delta
Build/NoCache-16 5.06s ± 1% 1.94s ± 1% -61.64% (p=0.008 n=5+5)
name old bin-B new bin-B delta
Build/NoCache-16 6.70M ± 0% 6.71M ± 0% +0.05% (p=0.008 n=5+5)
name old sys-time/op new sys-time/op delta
Build/NoCache-16 13.4s ± 2% 5.0s ± 2% -62.45% (p=0.008 n=5+5)
name old user-time/op new user-time/op delta
Build/NoCache-16 60.6s ± 1% 19.8s ± 1% -67.34% (p=0.008 n=5+5)
Since we only want to call "go list" one extra time,
instead of once for every package we find out we're missing,
we want to know what packages we could be missing in advance.
Resurrect a smarter version of the runtime-related script.
Finally, remove the runtime-related.txt test script,
as it has now been superseeded by the sanity checks in listPackage.
That is, obfuscating the runtime package will now panic if we are
missing any necessary package information.
To double check that we get the runtime's linkname edge case right,
make gogarble.txt use runtime/debug.WriteHeapDump,
which is implemented via a direct runtime linkname.
This ensures we don't lose test coverage from runtime-related.txt.
3 years ago
|
|
|
"runtime/debug"
|
|
|
|
|
"time"
|
|
|
|
|
"syscall"
|
only list missing packages when obfuscating the runtime
We were listing all of std, which certainly worked,
but was quite slow at over 200 packages.
In practice, we can only be missing up to 20-30 packages.
It was a good change as it fixed a severe bug,
but it also introduced a fairly noticeable slow-down.
The numbers are clear; this change shaves off multiple seconds when
obfuscating the runtime with a cold cache:
name old time/op new time/op delta
Build/NoCache-16 5.06s ± 1% 1.94s ± 1% -61.64% (p=0.008 n=5+5)
name old bin-B new bin-B delta
Build/NoCache-16 6.70M ± 0% 6.71M ± 0% +0.05% (p=0.008 n=5+5)
name old sys-time/op new sys-time/op delta
Build/NoCache-16 13.4s ± 2% 5.0s ± 2% -62.45% (p=0.008 n=5+5)
name old user-time/op new user-time/op delta
Build/NoCache-16 60.6s ± 1% 19.8s ± 1% -67.34% (p=0.008 n=5+5)
Since we only want to call "go list" one extra time,
instead of once for every package we find out we're missing,
we want to know what packages we could be missing in advance.
Resurrect a smarter version of the runtime-related script.
Finally, remove the runtime-related.txt test script,
as it has now been superseeded by the sanity checks in listPackage.
That is, obfuscating the runtime package will now panic if we are
missing any necessary package information.
To double check that we get the runtime's linkname edge case right,
make gogarble.txt use runtime/debug.WriteHeapDump,
which is implemented via a direct runtime linkname.
This ensures we don't lose test coverage from runtime-related.txt.
3 years ago
|
|
|
)
|
|
|
|
|
|
|
|
|
|
func main() {
|
|
|
|
|
// Ensure that embedded information in the runtime is missing.
|
|
|
|
|
fmt.Printf("runtime.GOROOT: %q\n", runtime.GOROOT())
|
|
|
|
|
fmt.Printf("runtime.Version: %q\n", runtime.Version())
|
|
|
|
|
|
|
|
|
|
// We just want to ensure these build and link OK, but we don't need to run them.
|
|
|
|
|
if len(os.Args) > 5 {
|
|
|
|
|
http.ListenAndServe("", nil)
|
|
|
|
|
// debug.WriteHeapDump is particularly interesting,
|
|
|
|
|
// as it is implemented by runtime via a linkname.
|
|
|
|
|
debug.WriteHeapDump(1)
|
|
|
|
|
time.Now()
|
|
|
|
|
syscall.Listen(0, 1)
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
-- stdimporter.stdout --
|
|
|
|
|
runtime.GOROOT: ""
|
|
|
|
|
runtime.Version: "unknown"
|