diff options
Diffstat (limited to 'tools/nogo')
| -rw-r--r-- | tools/nogo/BUILD | 49 | ||||
| -rw-r--r-- | tools/nogo/README.md | 31 | ||||
| -rw-r--r-- | tools/nogo/build.go | 36 | ||||
| -rw-r--r-- | tools/nogo/check/BUILD | 12 | ||||
| -rw-r--r-- | tools/nogo/check/main.go | 24 | ||||
| -rw-r--r-- | tools/nogo/config.go | 116 | ||||
| -rw-r--r-- | tools/nogo/data/BUILD | 10 | ||||
| -rw-r--r-- | tools/nogo/data/data.go | 21 | ||||
| -rw-r--r-- | tools/nogo/defs.bzl | 172 | ||||
| -rw-r--r-- | tools/nogo/io_bazel_rules_go-visibility.patch | 25 | ||||
| -rw-r--r-- | tools/nogo/matchers.go | 138 | ||||
| -rw-r--r-- | tools/nogo/nogo.go | 316 | ||||
| -rw-r--r-- | tools/nogo/register.go | 64 |
13 files changed, 1014 insertions, 0 deletions
diff --git a/tools/nogo/BUILD b/tools/nogo/BUILD new file mode 100644 index 000000000..c21b09511 --- /dev/null +++ b/tools/nogo/BUILD @@ -0,0 +1,49 @@ +load("//tools:defs.bzl", "go_library") + +package(licenses = ["notice"]) + +go_library( + name = "nogo", + srcs = [ + "build.go", + "config.go", + "matchers.go", + "nogo.go", + "register.go", + ], + nogo = False, + visibility = ["//:sandbox"], + deps = [ + "//tools/checkescape", + "//tools/checkunsafe", + "//tools/nogo/data", + "@org_golang_x_tools//go/analysis:go_tool_library", + "@org_golang_x_tools//go/analysis/internal/facts:go_tool_library", + "@org_golang_x_tools//go/analysis/passes/asmdecl:go_tool_library", + "@org_golang_x_tools//go/analysis/passes/assign:go_tool_library", + "@org_golang_x_tools//go/analysis/passes/atomic:go_tool_library", + "@org_golang_x_tools//go/analysis/passes/bools:go_tool_library", + "@org_golang_x_tools//go/analysis/passes/buildtag:go_tool_library", + "@org_golang_x_tools//go/analysis/passes/cgocall:go_tool_library", + "@org_golang_x_tools//go/analysis/passes/composite:go_tool_library", + "@org_golang_x_tools//go/analysis/passes/copylock:go_tool_library", + "@org_golang_x_tools//go/analysis/passes/errorsas:go_tool_library", + "@org_golang_x_tools//go/analysis/passes/httpresponse:go_tool_library", + "@org_golang_x_tools//go/analysis/passes/loopclosure:go_tool_library", + "@org_golang_x_tools//go/analysis/passes/lostcancel:go_tool_library", + "@org_golang_x_tools//go/analysis/passes/nilfunc:go_tool_library", + "@org_golang_x_tools//go/analysis/passes/nilness:go_tool_library", + "@org_golang_x_tools//go/analysis/passes/printf:go_tool_library", + "@org_golang_x_tools//go/analysis/passes/shadow:go_tool_library", + "@org_golang_x_tools//go/analysis/passes/shift:go_tool_library", + "@org_golang_x_tools//go/analysis/passes/stdmethods:go_tool_library", + "@org_golang_x_tools//go/analysis/passes/stringintconv:go_tool_library", + "@org_golang_x_tools//go/analysis/passes/structtag:go_tool_library", + "@org_golang_x_tools//go/analysis/passes/tests:go_tool_library", + "@org_golang_x_tools//go/analysis/passes/unmarshal:go_tool_library", + "@org_golang_x_tools//go/analysis/passes/unreachable:go_tool_library", + "@org_golang_x_tools//go/analysis/passes/unsafeptr:go_tool_library", + "@org_golang_x_tools//go/analysis/passes/unusedresult:go_tool_library", + "@org_golang_x_tools//go/gcexportdata:go_tool_library", + ], +) diff --git a/tools/nogo/README.md b/tools/nogo/README.md new file mode 100644 index 000000000..6e4db18de --- /dev/null +++ b/tools/nogo/README.md @@ -0,0 +1,31 @@ +# Extended "nogo" analysis + +This package provides a build aspect that perform nogo analysis. This will be +automatically injected to all relevant libraries when using the default +`go_binary` and `go_library` rules. + +It exists for several reasons. + +* The default `nogo` provided by bazel is insufficient with respect to the + possibility of binary analysis. This package allows us to analyze the + generated binary in addition to using the standard analyzers. + +* The configuration provided in this package is much richer than the standard + `nogo` JSON blob. Specifically, it allows us to exclude specific structures + from the composite rules (such as the Ranges that are common with the set + types). + +* The bazel version of `nogo` is run directly against the `go_library` and + `go_binary` targets, meaning that any change to the configuration requires a + rebuild from scratch (for some reason included all C++ source files in the + process). Using an aspect is more efficient in this regard. + +* The checks supported by this package are exported as tests, which makes it + easier to reason about and plumb into the build system. + +* For uninteresting reasons, it is impossible to integrate the default `nogo` + analyzer provided by bazel with internal Google tooling. To provide a + consistent experience, this package allows those systems to be unified. + +To use this package, import `nogo_test` from `defs.bzl` and add a single +dependency which is a `go_binary` or `go_library` rule. diff --git a/tools/nogo/build.go b/tools/nogo/build.go new file mode 100644 index 000000000..1c0d08661 --- /dev/null +++ b/tools/nogo/build.go @@ -0,0 +1,36 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package nogo + +import ( + "fmt" + "io" + "os" +) + +var ( + // internalPrefix is the internal path prefix. Note that this is not + // special, as paths should be passed relative to the repository root + // and should not have any special prefix applied. + internalPrefix = fmt.Sprintf("^") + + // externalPrefix is external workspace packages. + externalPrefix = "^external/" +) + +// findStdPkg needs to find the bundled standard library packages. +func findStdPkg(path, GOOS, GOARCH string) (io.ReadCloser, error) { + return os.Open(fmt.Sprintf("external/go_sdk/pkg/%s_%s/%s.a", GOOS, GOARCH, path)) +} diff --git a/tools/nogo/check/BUILD b/tools/nogo/check/BUILD new file mode 100644 index 000000000..e2d76cd5c --- /dev/null +++ b/tools/nogo/check/BUILD @@ -0,0 +1,12 @@ +load("//tools:defs.bzl", "go_binary") + +package(licenses = ["notice"]) + +# Note that the check binary must be public, since an aspect may be applied +# across lots of different rules in different repositories. +go_binary( + name = "check", + srcs = ["main.go"], + visibility = ["//visibility:public"], + deps = ["//tools/nogo"], +) diff --git a/tools/nogo/check/main.go b/tools/nogo/check/main.go new file mode 100644 index 000000000..3828edf3a --- /dev/null +++ b/tools/nogo/check/main.go @@ -0,0 +1,24 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// Binary check is the nogo entrypoint. +package main + +import ( + "gvisor.dev/gvisor/tools/nogo" +) + +func main() { + nogo.Main() +} diff --git a/tools/nogo/config.go b/tools/nogo/config.go new file mode 100644 index 000000000..6958fca69 --- /dev/null +++ b/tools/nogo/config.go @@ -0,0 +1,116 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package nogo + +import ( + "golang.org/x/tools/go/analysis" + "golang.org/x/tools/go/analysis/passes/asmdecl" + "golang.org/x/tools/go/analysis/passes/assign" + "golang.org/x/tools/go/analysis/passes/atomic" + "golang.org/x/tools/go/analysis/passes/bools" + "golang.org/x/tools/go/analysis/passes/buildtag" + "golang.org/x/tools/go/analysis/passes/cgocall" + "golang.org/x/tools/go/analysis/passes/composite" + "golang.org/x/tools/go/analysis/passes/copylock" + "golang.org/x/tools/go/analysis/passes/errorsas" + "golang.org/x/tools/go/analysis/passes/httpresponse" + "golang.org/x/tools/go/analysis/passes/loopclosure" + "golang.org/x/tools/go/analysis/passes/lostcancel" + "golang.org/x/tools/go/analysis/passes/nilfunc" + "golang.org/x/tools/go/analysis/passes/nilness" + "golang.org/x/tools/go/analysis/passes/printf" + "golang.org/x/tools/go/analysis/passes/shadow" + "golang.org/x/tools/go/analysis/passes/shift" + "golang.org/x/tools/go/analysis/passes/stdmethods" + "golang.org/x/tools/go/analysis/passes/stringintconv" + "golang.org/x/tools/go/analysis/passes/structtag" + "golang.org/x/tools/go/analysis/passes/tests" + "golang.org/x/tools/go/analysis/passes/unmarshal" + "golang.org/x/tools/go/analysis/passes/unreachable" + "golang.org/x/tools/go/analysis/passes/unsafeptr" + "golang.org/x/tools/go/analysis/passes/unusedresult" + + "gvisor.dev/gvisor/tools/checkescape" + "gvisor.dev/gvisor/tools/checkunsafe" +) + +var analyzerConfig = map[*analysis.Analyzer]matcher{ + // Standard analyzers. + asmdecl.Analyzer: alwaysMatches(), + assign.Analyzer: externalExcluded( + ".*gazelle/walk/walk.go", // False positive. + ), + atomic.Analyzer: alwaysMatches(), + bools.Analyzer: alwaysMatches(), + buildtag.Analyzer: alwaysMatches(), + cgocall.Analyzer: alwaysMatches(), + composite.Analyzer: and( + disableMatches(), // Disabled for now. + resultExcluded{ + "Object_", + "Range{", + }, + ), + copylock.Analyzer: internalMatches(), // Common external issues (e.g. protos). + errorsas.Analyzer: alwaysMatches(), + httpresponse.Analyzer: alwaysMatches(), + loopclosure.Analyzer: alwaysMatches(), + lostcancel.Analyzer: internalMatches(), // Common external issues. + nilfunc.Analyzer: alwaysMatches(), + nilness.Analyzer: and( + internalMatches(), // Common "tautological checks". + internalExcluded( + "pkg/sentry/platform/kvm/kvm_test.go", // Intentional. + "tools/bigquery/bigquery.go", // False positive. + ), + ), + printf.Analyzer: alwaysMatches(), + shift.Analyzer: alwaysMatches(), + stdmethods.Analyzer: internalMatches(), // Common external issues (e.g. methods named "Write"). + stringintconv.Analyzer: and( + internalExcluded(), + externalExcluded( + ".*protobuf/.*.go", // Bad conversions. + ".*flate/huffman_bit_writer.go", // Bad conversion. + ), + ), + shadow.Analyzer: disableMatches(), // Disabled for now. + structtag.Analyzer: internalMatches(), // External not subject to rules. + tests.Analyzer: alwaysMatches(), + unmarshal.Analyzer: alwaysMatches(), + unreachable.Analyzer: internalMatches(), + unsafeptr.Analyzer: and( + internalMatches(), + internalExcluded( + ".*_test.go", // Exclude tests. + "pkg/flipcall/.*_unsafe.go", // Special case. + "pkg/gohacks/gohacks_unsafe.go", // Special case. + "pkg/sentry/fs/fsutil/host_file_mapper_unsafe.go", // Special case. + "pkg/sentry/platform/kvm/bluepill_unsafe.go", // Special case. + "pkg/sentry/platform/kvm/machine_unsafe.go", // Special case. + "pkg/sentry/platform/ring0/pagetables/allocator_unsafe.go", // Special case. + "pkg/sentry/platform/safecopy/safecopy_unsafe.go", // Special case. + "pkg/sentry/vfs/mount_unsafe.go", // Special case. + "pkg/sentry/platform/systrap/stub_unsafe.go", // Special case. + "pkg/sentry/platform/systrap/switchto_google_unsafe.go", // Special case. + "pkg/sentry/platform/systrap/sysmsg_thread_unsafe.go", // Special case. + ), + ), + unusedresult.Analyzer: alwaysMatches(), + + // Internal analyzers: external packages not subject. + checkescape.Analyzer: internalMatches(), + checkunsafe.Analyzer: internalMatches(), +} diff --git a/tools/nogo/data/BUILD b/tools/nogo/data/BUILD new file mode 100644 index 000000000..b7564cc44 --- /dev/null +++ b/tools/nogo/data/BUILD @@ -0,0 +1,10 @@ +load("//tools:defs.bzl", "go_library") + +package(licenses = ["notice"]) + +go_library( + name = "data", + srcs = ["data.go"], + nogo = False, + visibility = ["//tools:__subpackages__"], +) diff --git a/tools/nogo/data/data.go b/tools/nogo/data/data.go new file mode 100644 index 000000000..eb84d0d27 --- /dev/null +++ b/tools/nogo/data/data.go @@ -0,0 +1,21 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// Package data contains shared data for nogo analysis. +// +// This is used to break a dependency cycle. +package data + +// Objdump is the dumped binary under analysis. +var Objdump string diff --git a/tools/nogo/defs.bzl b/tools/nogo/defs.bzl new file mode 100644 index 000000000..6560b57c8 --- /dev/null +++ b/tools/nogo/defs.bzl @@ -0,0 +1,172 @@ +"""Nogo rules.""" + +load("//tools/bazeldefs:defs.bzl", "go_context", "go_importpath", "go_rule") + +# NogoInfo is the serialized set of package facts for a nogo analysis. +# +# Each go_library rule will generate a corresponding nogo rule, which will run +# with the source files as input. Note however, that the individual nogo rules +# are simply stubs that enter into the shadow dependency tree (the "aspect"). +NogoInfo = provider( + fields = { + "facts": "serialized package facts", + "importpath": "package import path", + "binaries": "package binary files", + }, +) + +def _nogo_aspect_impl(target, ctx): + # If this is a nogo rule itself (and not the shadow of a go_library or + # go_binary rule created by such a rule), then we simply return nothing. + # All work is done in the shadow properties for go rules. For a proto + # library, we simply skip the analysis portion but still need to return a + # valid NogoInfo to reference the generated binary. + if ctx.rule.kind == "go_library": + srcs = ctx.rule.files.srcs + elif ctx.rule.kind == "go_proto_library" or ctx.rule.kind == "go_wrap_cc": + srcs = [] + else: + return [NogoInfo()] + + # Construct the Go environment from the go_context.env dictionary. + env_prefix = " ".join(["%s=%s" % (key, value) for (key, value) in go_context(ctx).env.items()]) + + # Start with all target files and srcs as input. + inputs = target.files.to_list() + srcs + + # Generate a shell script that dumps the binary. Annoyingly, this seems + # necessary as the context in which a run_shell command runs does not seem + # to cleanly allow us redirect stdout to the actual output file. Perhaps + # I'm missing something here, but the intermediate script does work. + binaries = target.files.to_list() + disasm_file = ctx.actions.declare_file(target.label.name + ".out") + dumper = ctx.actions.declare_file("%s-dumper" % ctx.label.name) + ctx.actions.write(dumper, "\n".join([ + "#!/bin/bash", + "%s %s tool objdump %s > %s\n" % ( + env_prefix, + go_context(ctx).go.path, + [f.path for f in binaries if f.path.endswith(".a")][0], + disasm_file.path, + ), + ]), is_executable = True) + ctx.actions.run( + inputs = binaries, + outputs = [disasm_file], + tools = go_context(ctx).runfiles, + mnemonic = "GoObjdump", + progress_message = "Objdump %s" % target.label, + executable = dumper, + ) + inputs.append(disasm_file) + + # Extract the importpath for this package. + importpath = go_importpath(target) + + # The nogo tool requires a configfile serialized in JSON format to do its + # work. This must line up with the nogo.Config fields. + facts = ctx.actions.declare_file(target.label.name + ".facts") + config = struct( + ImportPath = importpath, + GoFiles = [src.path for src in srcs if src.path.endswith(".go")], + NonGoFiles = [src.path for src in srcs if not src.path.endswith(".go")], + GOOS = go_context(ctx).goos, + GOARCH = go_context(ctx).goarch, + Tags = go_context(ctx).tags, + FactMap = {}, # Constructed below. + ImportMap = {}, # Constructed below. + FactOutput = facts.path, + Objdump = disasm_file.path, + ) + + # Collect all info from shadow dependencies. + for dep in ctx.rule.attr.deps: + # There will be no file attribute set for all transitive dependencies + # that are not go_library or go_binary rules, such as a proto rules. + # This is handled by the ctx.rule.kind check above. + info = dep[NogoInfo] + if not hasattr(info, "facts"): + continue + + # Configure where to find the binary & fact files. Note that this will + # use .x and .a regardless of whether this is a go_binary rule, since + # these dependencies must be go_library rules. + x_files = [f.path for f in info.binaries if f.path.endswith(".x")] + if not len(x_files): + x_files = [f.path for f in info.binaries if f.path.endswith(".a")] + config.ImportMap[info.importpath] = x_files[0] + config.FactMap[info.importpath] = info.facts.path + + # Ensure the above are available as inputs. + inputs.append(info.facts) + inputs += info.binaries + + # Write the configuration and run the tool. + config_file = ctx.actions.declare_file(target.label.name + ".cfg") + ctx.actions.write(config_file, config.to_json()) + inputs.append(config_file) + + # Run the nogo tool itself. + ctx.actions.run( + inputs = inputs, + outputs = [facts], + tools = go_context(ctx).runfiles, + executable = ctx.files._nogo[0], + mnemonic = "GoStaticAnalysis", + progress_message = "Analyzing %s" % target.label, + arguments = ["-config=%s" % config_file.path], + ) + + # Return the package facts as output. + return [NogoInfo( + facts = facts, + importpath = importpath, + binaries = binaries, + )] + +nogo_aspect = go_rule( + aspect, + implementation = _nogo_aspect_impl, + attr_aspects = ["deps"], + attrs = { + "_nogo": attr.label( + default = "//tools/nogo/check:check", + allow_single_file = True, + ), + }, +) + +def _nogo_test_impl(ctx): + """Check nogo findings.""" + + # Build a runner that checks for the existence of the facts file. Note that + # the actual build will fail in the case of a broken analysis. We things + # this way so that any test applied is effectively pushed down to all + # upstream dependencies through the aspect. + inputs = [] + runner = ctx.actions.declare_file("%s-executer" % ctx.label.name) + runner_content = ["#!/bin/bash"] + for dep in ctx.attr.deps: + info = dep[NogoInfo] + inputs.append(info.facts) + + # Draw a sweet unicode checkmark with the package name (in green). + runner_content.append("echo -e \"\\033[0;32m\\xE2\\x9C\\x94\\033[0;31m\\033[0m %s\"" % info.importpath) + runner_content.append("exit 0\n") + ctx.actions.write(runner, "\n".join(runner_content), is_executable = True) + return [DefaultInfo( + runfiles = ctx.runfiles(files = inputs), + executable = runner, + )] + +_nogo_test = rule( + implementation = _nogo_test_impl, + attrs = { + "deps": attr.label_list(aspects = [nogo_aspect]), + }, + test = True, +) + +def nogo_test(**kwargs): + tags = kwargs.pop("tags", []) + ["nogo"] + _nogo_test(tags = tags, **kwargs) diff --git a/tools/nogo/io_bazel_rules_go-visibility.patch b/tools/nogo/io_bazel_rules_go-visibility.patch new file mode 100644 index 000000000..6b64b2e85 --- /dev/null +++ b/tools/nogo/io_bazel_rules_go-visibility.patch @@ -0,0 +1,25 @@ +diff --git a/third_party/org_golang_x_tools-extras.patch b/third_party/org_golang_x_tools-extras.patch +index 133fbccc..5f0d9a47 100644 +--- a/third_party/org_golang_x_tools-extras.patch ++++ b/third_party/org_golang_x_tools-extras.patch +@@ -32,7 +32,7 @@ diff -urN c/go/analysis/internal/facts/BUILD.bazel d/go/analysis/internal/facts/ + + go_library( + name = "go_default_library", +-@@ -14,6 +14,23 @@ ++@@ -14,6 +14,20 @@ + ], + ) + +@@ -43,10 +43,7 @@ diff -urN c/go/analysis/internal/facts/BUILD.bazel d/go/analysis/internal/facts/ + + "imports.go", + + ], + + importpath = "golang.org/x/tools/go/analysis/internal/facts", +-+ visibility = [ +-+ "//go/analysis:__subpackages__", +-+ "@io_bazel_rules_go//go/tools/builders:__pkg__", +-+ ], +++ visibility = ["//visibility:public"], + + deps = [ + + "//go/analysis:go_tool_library", + + "//go/types/objectpath:go_tool_library", diff --git a/tools/nogo/matchers.go b/tools/nogo/matchers.go new file mode 100644 index 000000000..bc5772303 --- /dev/null +++ b/tools/nogo/matchers.go @@ -0,0 +1,138 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package nogo + +import ( + "go/token" + "path/filepath" + "regexp" + "strings" + + "golang.org/x/tools/go/analysis" +) + +type matcher interface { + ShouldReport(d analysis.Diagnostic, fs *token.FileSet) bool +} + +// pathRegexps excludes explicit paths. +type pathRegexps struct { + expr []*regexp.Regexp + whitelist bool +} + +// buildRegexps builds a list of regular expressions. +// +// This will panic on error. +func buildRegexps(prefix string, args ...string) []*regexp.Regexp { + result := make([]*regexp.Regexp, 0, len(args)) + for _, arg := range args { + result = append(result, regexp.MustCompile(filepath.Join(prefix, arg))) + } + return result +} + +// ShouldReport implements matcher.ShouldReport. +func (p *pathRegexps) ShouldReport(d analysis.Diagnostic, fs *token.FileSet) bool { + fullPos := fs.Position(d.Pos).String() + for _, path := range p.expr { + if path.MatchString(fullPos) { + return p.whitelist + } + } + return !p.whitelist +} + +// internalExcluded excludes specific internal paths. +func internalExcluded(paths ...string) *pathRegexps { + return &pathRegexps{ + expr: buildRegexps(internalPrefix, paths...), + whitelist: false, + } +} + +// excludedExcluded excludes specific external paths. +func externalExcluded(paths ...string) *pathRegexps { + return &pathRegexps{ + expr: buildRegexps(externalPrefix, paths...), + whitelist: false, + } +} + +// internalMatches returns a path matcher for internal packages. +func internalMatches() *pathRegexps { + return &pathRegexps{ + expr: buildRegexps(internalPrefix, ".*"), + whitelist: true, + } +} + +// resultExcluded excludes explicit message contents. +type resultExcluded []string + +// ShouldReport implements matcher.ShouldReport. +func (r resultExcluded) ShouldReport(d analysis.Diagnostic, _ *token.FileSet) bool { + for _, str := range r { + if strings.Contains(d.Message, str) { + return false + } + } + return true // Not blacklisted. +} + +// andMatcher is a composite matcher. +type andMatcher struct { + first matcher + second matcher +} + +// ShouldReport implements matcher.ShouldReport. +func (a *andMatcher) ShouldReport(d analysis.Diagnostic, fs *token.FileSet) bool { + return a.first.ShouldReport(d, fs) && a.second.ShouldReport(d, fs) +} + +// and is a syntactic convension for andMatcher. +func and(first matcher, second matcher) *andMatcher { + return &andMatcher{ + first: first, + second: second, + } +} + +// anyMatcher matches everything. +type anyMatcher struct{} + +// ShouldReport implements matcher.ShouldReport. +func (anyMatcher) ShouldReport(analysis.Diagnostic, *token.FileSet) bool { + return true +} + +// alwaysMatches returns an anyMatcher instance. +func alwaysMatches() anyMatcher { + return anyMatcher{} +} + +// neverMatcher will never match. +type neverMatcher struct{} + +// ShouldReport implements matcher.ShouldReport. +func (neverMatcher) ShouldReport(analysis.Diagnostic, *token.FileSet) bool { + return false +} + +// disableMatches returns a neverMatcher instance. +func disableMatches() neverMatcher { + return neverMatcher{} +} diff --git a/tools/nogo/nogo.go b/tools/nogo/nogo.go new file mode 100644 index 000000000..203cdf688 --- /dev/null +++ b/tools/nogo/nogo.go @@ -0,0 +1,316 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// Package nogo implements binary analysis similar to bazel's nogo, +// or the unitchecker package. It exists in order to provide additional +// facilities for analysis, namely plumbing through the output from +// dumping the generated binary (to analyze actual produced code). +package nogo + +import ( + "encoding/json" + "flag" + "fmt" + "go/ast" + "go/build" + "go/parser" + "go/token" + "go/types" + "io" + "io/ioutil" + "log" + "os" + "path/filepath" + "reflect" + + "golang.org/x/tools/go/analysis" + "golang.org/x/tools/go/analysis/internal/facts" + "golang.org/x/tools/go/gcexportdata" + "gvisor.dev/gvisor/tools/nogo/data" +) + +// pkgConfig is serialized as the configuration. +// +// This contains everything required for the analysis. +type pkgConfig struct { + ImportPath string + GoFiles []string + NonGoFiles []string + Tags []string + GOOS string + GOARCH string + ImportMap map[string]string + FactMap map[string]string + FactOutput string + Objdump string +} + +// loadFacts finds and loads facts per FactMap. +func (c *pkgConfig) loadFacts(path string) ([]byte, error) { + realPath, ok := c.FactMap[path] + if !ok { + return nil, nil // No facts available. + } + + // Read the files file. + data, err := ioutil.ReadFile(realPath) + if err != nil { + return nil, err + } + return data, nil +} + +// shouldInclude indicates whether the file should be included. +// +// NOTE: This does only basic parsing of tags. +func (c *pkgConfig) shouldInclude(path string) (bool, error) { + ctx := build.Default + ctx.GOOS = c.GOOS + ctx.GOARCH = c.GOARCH + ctx.BuildTags = c.Tags + return ctx.MatchFile(filepath.Dir(path), filepath.Base(path)) +} + +// importer is an implementation of go/types.Importer. +// +// This wraps a configuration, which provides the map of package names to +// files, and the facts. Note that this importer implementation will always +// pass when a given package is not available. +type importer struct { + pkgConfig + fset *token.FileSet + cache map[string]*types.Package +} + +// Import implements types.Importer.Import. +func (i *importer) Import(path string) (*types.Package, error) { + if path == "unsafe" { + // Special case: go/types has pre-defined type information for + // unsafe. We ensure that this package is correct, in case any + // analyzers are specifically looking for this. + return types.Unsafe, nil + } + realPath, ok := i.ImportMap[path] + var ( + rc io.ReadCloser + err error + ) + if !ok { + // Not found in the import path. Attempt to find the package + // via the standard library. + rc, err = findStdPkg(path, i.GOOS, i.GOARCH) + } else { + // Open the file. + rc, err = os.Open(realPath) + } + if err != nil { + return nil, err + } + defer rc.Close() + + // Load all exported data. + r, err := gcexportdata.NewReader(rc) + if err != nil { + return nil, err + } + + return gcexportdata.Read(r, i.fset, i.cache, path) +} + +// checkPackage runs all analyzers. +// +// The implementation was adapted from [1], which was in turn adpated from [2]. +// This returns a list of matching analysis issues, or an error if the analysis +// could not be completed. +// +// [1] bazelbuid/rules_go/tools/builders/nogo_main.go +// [2] golang.org/x/tools/go/checker/internal/checker +func checkPackage(config pkgConfig) ([]string, error) { + imp := &importer{ + pkgConfig: config, + fset: token.NewFileSet(), + cache: make(map[string]*types.Package), + } + + // Load all source files. + var syntax []*ast.File + for _, file := range config.GoFiles { + include, err := config.shouldInclude(file) + if err != nil { + return nil, fmt.Errorf("error evaluating file %q: %v", file, err) + } + if !include { + continue + } + s, err := parser.ParseFile(imp.fset, file, nil, parser.ParseComments) + if err != nil { + return nil, fmt.Errorf("error parsing file %q: %v", file, err) + } + syntax = append(syntax, s) + } + + // Check type information. + typesSizes := types.SizesFor("gc", config.GOARCH) + typeConfig := types.Config{Importer: imp} + typesInfo := &types.Info{ + Types: make(map[ast.Expr]types.TypeAndValue), + Uses: make(map[*ast.Ident]types.Object), + Defs: make(map[*ast.Ident]types.Object), + Implicits: make(map[ast.Node]types.Object), + Scopes: make(map[ast.Node]*types.Scope), + Selections: make(map[*ast.SelectorExpr]*types.Selection), + } + types, err := typeConfig.Check(config.ImportPath, imp.fset, syntax, typesInfo) + if err != nil { + return nil, fmt.Errorf("error checking types: %v", err) + } + + // Load all package facts. + facts, err := facts.Decode(types, config.loadFacts) + if err != nil { + return nil, fmt.Errorf("error decoding facts: %v", err) + } + + // Set the binary global for use. + data.Objdump = config.Objdump + + // Register fact types and establish dependencies between analyzers. + // The visit closure will execute recursively, and populate results + // will all required analysis results. + diagnostics := make(map[*analysis.Analyzer][]analysis.Diagnostic) + results := make(map[*analysis.Analyzer]interface{}) + var visit func(*analysis.Analyzer) error // For recursion. + visit = func(a *analysis.Analyzer) error { + if _, ok := results[a]; ok { + return nil + } + + // Run recursively for all dependencies. + for _, req := range a.Requires { + if err := visit(req); err != nil { + return err + } + } + + // Prepare the matcher. + m := analyzerConfig[a] + report := func(d analysis.Diagnostic) { + if m.ShouldReport(d, imp.fset) { + diagnostics[a] = append(diagnostics[a], d) + } + } + + // Run the analysis. + factFilter := make(map[reflect.Type]bool) + for _, f := range a.FactTypes { + factFilter[reflect.TypeOf(f)] = true + } + p := &analysis.Pass{ + Analyzer: a, + Fset: imp.fset, + Files: syntax, + Pkg: types, + TypesInfo: typesInfo, + ResultOf: results, // All results. + Report: report, + ImportPackageFact: facts.ImportPackageFact, + ExportPackageFact: facts.ExportPackageFact, + ImportObjectFact: facts.ImportObjectFact, + ExportObjectFact: facts.ExportObjectFact, + AllPackageFacts: func() []analysis.PackageFact { return facts.AllPackageFacts(factFilter) }, + AllObjectFacts: func() []analysis.ObjectFact { return facts.AllObjectFacts(factFilter) }, + TypesSizes: typesSizes, + } + result, err := a.Run(p) + if err != nil { + return fmt.Errorf("error running analysis %s: %v", a, err) + } + + // Sanity check & save the result. + if got, want := reflect.TypeOf(result), a.ResultType; got != want { + return fmt.Errorf("error: analyzer %s returned a result of type %v, but declared ResultType %v", a, got, want) + } + results[a] = result + return nil // Success. + } + + // Visit all analysis recursively. + for a, _ := range analyzerConfig { + if err := visit(a); err != nil { + return nil, err // Already has context. + } + } + + // Write the output file. + if config.FactOutput != "" { + factData := facts.Encode() + if err := ioutil.WriteFile(config.FactOutput, factData, 0644); err != nil { + return nil, fmt.Errorf("error: unable to open facts output %q: %v", config.FactOutput, err) + } + } + + // Convert all diagnostics to strings. + findings := make([]string, 0, len(diagnostics)) + for a, ds := range diagnostics { + for _, d := range ds { + // Include the anlyzer name for debugability and configuration. + findings = append(findings, fmt.Sprintf("%s: %s: %s", a.Name, imp.fset.Position(d.Pos), d.Message)) + } + } + + // Return all findings. + return findings, nil +} + +var ( + configFile = flag.String("config", "", "configuration file (in JSON format)") +) + +// Main is the entrypoint; it should be called directly from main. +// +// N.B. This package registers it's own flags. +func Main() { + // Parse all flags. + flag.Parse() + + // Load the configuration. + f, err := os.Open(*configFile) + if err != nil { + log.Fatalf("unable to open configuration %q: %v", *configFile, err) + } + defer f.Close() + config := new(pkgConfig) + dec := json.NewDecoder(f) + dec.DisallowUnknownFields() + if err := dec.Decode(config); err != nil { + log.Fatalf("unable to decode configuration: %v", err) + } + + // Process the package. + findings, err := checkPackage(*config) + if err != nil { + log.Fatalf("error checking package: %v", err) + } + + // No findings? + if len(findings) == 0 { + os.Exit(0) + } + + // Print findings and exit with non-zero code. + for _, finding := range findings { + fmt.Fprintf(os.Stdout, "%s\n", finding) + } + os.Exit(1) +} diff --git a/tools/nogo/register.go b/tools/nogo/register.go new file mode 100644 index 000000000..62b499661 --- /dev/null +++ b/tools/nogo/register.go @@ -0,0 +1,64 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package nogo + +import ( + "encoding/gob" + "log" + + "golang.org/x/tools/go/analysis" +) + +// analyzers returns all configured analyzers. +func analyzers() (all []*analysis.Analyzer) { + for a, _ := range analyzerConfig { + all = append(all, a) + } + return all +} + +func init() { + // Validate basic configuration. + if err := analysis.Validate(analyzers()); err != nil { + log.Fatalf("unable to validate analyzer: %v", err) + } + + // Register all fact types. + // + // N.B. This needs to be done recursively, because there may be + // analyzers in the Requires list that do not appear explicitly above. + registered := make(map[*analysis.Analyzer]struct{}) + var register func(*analysis.Analyzer) + register = func(a *analysis.Analyzer) { + if _, ok := registered[a]; ok { + return + } + + // Regsiter dependencies. + for _, da := range a.Requires { + register(da) + } + + // Register local facts. + for _, f := range a.FactTypes { + gob.Register(f) + } + + registered[a] = struct{}{} // Done. + } + for _, a := range analyzers() { + register(a) + } +} |