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-rw-r--r--tools/nogo/nogo.go673
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diff --git a/tools/nogo/nogo.go b/tools/nogo/nogo.go
deleted file mode 100644
index a96cb400a..000000000
--- a/tools/nogo/nogo.go
+++ /dev/null
@@ -1,673 +0,0 @@
-// 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 (
- "bytes"
- "encoding/gob"
- "errors"
- "fmt"
- "go/ast"
- "go/build"
- "go/parser"
- "go/token"
- "go/types"
- "io"
- "io/ioutil"
- "log"
- "os"
- "path"
- "path/filepath"
- "reflect"
- "sort"
- "strings"
-
- "golang.org/x/tools/go/analysis"
- "golang.org/x/tools/go/analysis/internal/facts"
- "golang.org/x/tools/go/gcexportdata"
- "golang.org/x/tools/go/types/objectpath"
-
- // Special case: flags live here and change overall behavior.
- "gvisor.dev/gvisor/tools/nogo/objdump"
- "gvisor.dev/gvisor/tools/worker"
-)
-
-// StdlibConfig is serialized as the configuration.
-//
-// This contains everything required for stdlib analysis.
-type StdlibConfig struct {
- Srcs []string
- GOOS string
- GOARCH string
- BuildTags []string
- ReleaseTags []string // Use build.Default if nil.
-}
-
-// PackageConfig is serialized as the configuration.
-//
-// This contains everything required for single package analysis.
-type PackageConfig struct {
- ImportPath string
- GoFiles []string
- NonGoFiles []string
- BuildTags []string
- ReleaseTags []string // Use build.Default if nil.
- GOOS string
- GOARCH string
- ImportMap map[string]string
- FactMap map[string]string
- StdlibFacts string
-}
-
-// loader is a fact-loader function.
-type loader func(string) ([]byte, error)
-
-// saver is a fact-saver function.
-type saver func([]byte) error
-
-// stdlibFact is used for serialiation.
-type stdlibFact struct {
- Package string
- Facts []byte
-}
-
-// stdlibFacts is a set of standard library facts.
-type stdlibFacts map[string][]byte
-
-// Size implements worker.Sizer.Size.
-func (sf stdlibFacts) Size() int64 {
- size := int64(0)
- for filename, data := range sf {
- size += int64(len(filename))
- size += int64(len(data))
- }
- return size
-}
-
-// EncodeTo serializes stdlibFacts.
-func (sf stdlibFacts) EncodeTo(w io.Writer) error {
- stdlibFactsSorted := make([]stdlibFact, 0, len(sf))
- for pkg, facts := range sf {
- stdlibFactsSorted = append(stdlibFactsSorted, stdlibFact{
- Package: pkg,
- Facts: facts,
- })
- }
- sort.Slice(stdlibFactsSorted, func(i, j int) bool {
- return stdlibFactsSorted[i].Package < stdlibFactsSorted[j].Package
- })
- enc := gob.NewEncoder(w)
- if err := enc.Encode(stdlibFactsSorted); err != nil {
- return err
- }
- return nil
-}
-
-// DecodeFrom deserializes stdlibFacts.
-func (sf stdlibFacts) DecodeFrom(r io.Reader) error {
- var stdlibFactsSorted []stdlibFact
- dec := gob.NewDecoder(r)
- if err := dec.Decode(&stdlibFactsSorted); err != nil {
- return err
- }
- for _, stdlibFact := range stdlibFactsSorted {
- sf[stdlibFact.Package] = stdlibFact.Facts
- }
- return nil
-}
-
-var (
- // cachedFacts caches by file (just byte data).
- cachedFacts = worker.NewCache("facts")
-
- // stdlibCachedFacts caches the standard library (stdlibFacts).
- stdlibCachedFacts = worker.NewCache("stdlib")
-)
-
-// factLoader loads facts.
-func (c *PackageConfig) factLoader(path string) (data []byte, err error) {
- filename, ok := c.FactMap[path]
- if ok {
- cb := cachedFacts.Lookup([]string{filename}, func() worker.Sizer {
- data, readErr := ioutil.ReadFile(filename)
- if readErr != nil {
- err = fmt.Errorf("error loading %q: %w", filename, readErr)
- return nil
- }
- return worker.CacheBytes(data)
- })
- if cb != nil {
- return []byte(cb.(worker.CacheBytes)), err
- }
- return nil, err
- }
- cb := stdlibCachedFacts.Lookup([]string{c.StdlibFacts}, func() worker.Sizer {
- r, openErr := os.Open(c.StdlibFacts)
- if openErr != nil {
- err = fmt.Errorf("error loading stdlib facts from %q: %w", c.StdlibFacts, openErr)
- return nil
- }
- defer r.Close()
- sf := make(stdlibFacts)
- if readErr := sf.DecodeFrom(r); readErr != nil {
- err = fmt.Errorf("error loading stdlib facts: %w", readErr)
- return nil
- }
- return sf
- })
- if cb != nil {
- return (cb.(stdlibFacts))[path], err
- }
- return nil, err
-}
-
-// shouldInclude indicates whether the file should be included.
-//
-// NOTE: This does only basic parsing of tags.
-func (c *PackageConfig) shouldInclude(path string) (bool, error) {
- ctx := build.Default
- ctx.GOOS = c.GOOS
- ctx.GOARCH = c.GOARCH
- ctx.BuildTags = c.BuildTags
- if c.ReleaseTags != nil {
- ctx.ReleaseTags = c.ReleaseTags
- }
- 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 {
- *PackageConfig
- fset *token.FileSet
- cache map[string]*types.Package
- lastErr error
- callback func(string) error
-}
-
-// 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
- }
-
- // Call the internal callback. This is used to resolve loading order
- // for the standard library. See checkStdlib.
- if i.callback != nil {
- if err := i.callback(path); err != nil {
- i.lastErr = err
- return nil, err
- }
- }
-
- // Check the cache.
- if pkg, ok := i.cache[path]; ok && pkg.Complete() {
- return pkg, nil
- }
-
- // Actually load the data.
- 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(i.GOOS, i.GOARCH, path)
- } else {
- // Open the file.
- rc, err = os.Open(realPath)
- }
- if err != nil {
- i.lastErr = err
- 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)
-}
-
-// ErrSkip indicates the package should be skipped.
-var ErrSkip = errors.New("skipped")
-
-// CheckStdlib checks the standard library.
-//
-// This constructs a synthetic package configuration for each library in the
-// standard library sources, and call CheckPackage repeatedly.
-//
-// Note that not all parts of the source are expected to build. We skip obvious
-// test files, and cmd files, which should not be dependencies.
-func CheckStdlib(config *StdlibConfig, analyzers []*analysis.Analyzer) (allFindings FindingSet, facts []byte, err error) {
- if len(config.Srcs) == 0 {
- return nil, nil, nil
- }
-
- // Ensure all paths are normalized.
- for i := 0; i < len(config.Srcs); i++ {
- config.Srcs[i] = path.Clean(config.Srcs[i])
- }
-
- // Calculate the root source directory. This is always a directory
- // named 'src', of which we simply take the first we find. This is a
- // bit fragile, but works for all currently known Go source
- // configurations.
- //
- // Note that there may be extra files outside of the root source
- // directory; we simply ignore those.
- rootSrcPrefix := ""
- for _, file := range config.Srcs {
- const src = "/src/"
- i := strings.Index(file, src)
- if i == -1 {
- // Superfluous file.
- continue
- }
-
- // Index of first character after /src/.
- i += len(src)
- rootSrcPrefix = file[:i]
- break
- }
-
- // Go standard library packages using Go 1.18 type parameter features.
- //
- // As of writing, analysis tooling is not updated to support type
- // parameters and will choke on these packages. We skip these packages
- // entirely for now.
- //
- // TODO(b/201686256): remove once tooling can handle type parameters.
- usesTypeParams := map[string]struct{}{
- "constraints": struct{}{}, // golang.org/issue/45458
- "maps": struct{}{}, // golang.org/issue/47649
- "slices": struct{}{}, // golang.org/issue/45955
- }
-
- // Aggregate all files by directory.
- packages := make(map[string]*PackageConfig)
- for _, file := range config.Srcs {
- if !strings.HasPrefix(file, rootSrcPrefix) {
- // Superflouous file.
- continue
- }
-
- d := path.Dir(file)
- if len(rootSrcPrefix) >= len(d) {
- continue // Not a file.
- }
- pkg := d[len(rootSrcPrefix):]
-
- // Skip cmd packages and obvious test files: see above.
- if strings.HasPrefix(pkg, "cmd/") || strings.HasSuffix(file, "_test.go") {
- continue
- }
-
- if _, ok := usesTypeParams[pkg]; ok {
- log.Printf("WARNING: Skipping package %q: type param analysis not yet supported", pkg)
- continue
- }
-
- c, ok := packages[pkg]
- if !ok {
- c = &PackageConfig{
- ImportPath: pkg,
- GOOS: config.GOOS,
- GOARCH: config.GOARCH,
- BuildTags: config.BuildTags,
- ReleaseTags: config.ReleaseTags,
- }
- packages[pkg] = c
- }
- // Add the files appropriately. Note that they will be further
- // filtered by architecture and build tags below, so this need
- // not be done immediately.
- if strings.HasSuffix(file, ".go") {
- c.GoFiles = append(c.GoFiles, file)
- } else {
- c.NonGoFiles = append(c.NonGoFiles, file)
- }
- }
-
- // Closure to check a single package.
- localStdlibFacts := make(stdlibFacts)
- localStdlibErrs := make(map[string]error)
- stdlibCachedFacts.Lookup([]string{""}, func() worker.Sizer {
- return localStdlibFacts
- })
- var checkOne func(pkg string) error // Recursive.
- checkOne = func(pkg string) error {
- // Is this already done?
- if _, ok := localStdlibFacts[pkg]; ok {
- return nil
- }
- // Did this fail previously?
- if _, ok := localStdlibErrs[pkg]; ok {
- return nil
- }
-
- // Lookup the configuration.
- config, ok := packages[pkg]
- if !ok {
- return nil // Not known.
- }
-
- // Find the binary package, and provide to objdump.
- rc, err := findStdPkg(config.GOOS, config.GOARCH, pkg)
- if err != nil {
- // If there's no binary for this package, it is likely
- // not built with the distribution. That's fine, we can
- // just skip analysis.
- localStdlibErrs[pkg] = err
- return nil
- }
-
- // Provide the input.
- oldReader := objdump.Reader
- objdump.Reader = rc // For analysis.
- defer func() {
- rc.Close()
- objdump.Reader = oldReader // Restore.
- }()
-
- // Run the analysis.
- findings, factData, err := CheckPackage(config, analyzers, checkOne)
- if err != nil {
- // If we can't analyze a package from the standard library,
- // then we skip it. It will simply not have any findings.
- localStdlibErrs[pkg] = err
- return nil
- }
- localStdlibFacts[pkg] = factData
- allFindings = append(allFindings, findings...)
- return nil
- }
-
- // Check all packages.
- //
- // Note that this may call checkOne recursively, so it's not guaranteed
- // to evaluate in the order provided here. We do ensure however, that
- // all packages are evaluated.
- for pkg := range packages {
- if err := checkOne(pkg); err != nil {
- return nil, nil, err
- }
- }
-
- // Sanity check.
- if len(localStdlibFacts) == 0 {
- return nil, nil, fmt.Errorf("no stdlib facts found: misconfiguration?")
- }
-
- // Write out all findings.
- buf := bytes.NewBuffer(nil)
- if err := localStdlibFacts.EncodeTo(buf); err != nil {
- return nil, nil, fmt.Errorf("error serialized stdlib facts: %v", err)
- }
-
- // Write out all errors.
- for pkg, err := range localStdlibErrs {
- log.Printf("WARNING: error while processing %v: %v", pkg, err)
- }
-
- // Return all findings.
- return allFindings, buf.Bytes(), nil
-}
-
-// sanityCheckScope checks that all object in astTypes map to the correct
-// objects in binaryTypes. Note that we don't check whether the sets are the
-// same, we only care about the fidelity of objects in astTypes.
-//
-// When an inconsistency is identified, we record it in the astToBinaryMap.
-// This allows us to dynamically replace facts and correct for the issue. The
-// total number of mismatches is returned.
-func sanityCheckScope(astScope *types.Scope, binaryTypes *types.Package, binaryScope *types.Scope, astToBinary map[types.Object]types.Object) error {
- for _, x := range astScope.Names() {
- fe := astScope.Lookup(x)
- path, err := objectpath.For(fe)
- if err != nil {
- continue // Not an encoded object.
- }
- se, err := objectpath.Object(binaryTypes, path)
- if err != nil {
- continue // May be unused, see below.
- }
- if fe.Id() != se.Id() {
- // These types are incompatible. This means that when
- // this objectpath is loading from the binaryTypes (for
- // dependencies) it will resolve to a fact for that
- // type. We don't actually care about this error since
- // we do the rewritten, but may as well alert.
- log.Printf("WARNING: Object %s is a victim of go/issues/44195.", fe.Id())
- }
- se = binaryScope.Lookup(x)
- if se == nil {
- // The fact may not be exported in the objectdata, if
- // it is package internal. This is fine, as nothing out
- // of this package can use these symbols.
- continue
- }
- // Save the translation.
- astToBinary[fe] = se
- }
- for i := 0; i < astScope.NumChildren(); i++ {
- if err := sanityCheckScope(astScope.Child(i), binaryTypes, binaryScope, astToBinary); err != nil {
- return err
- }
- }
- return nil
-}
-
-// sanityCheckTypes checks that two types are sane. The total number of
-// mismatches is returned.
-func sanityCheckTypes(astTypes, binaryTypes *types.Package, astToBinary map[types.Object]types.Object) error {
- return sanityCheckScope(astTypes.Scope(), binaryTypes, binaryTypes.Scope(), astToBinary)
-}
-
-// CheckPackage runs all given 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 *PackageConfig, analyzers []*analysis.Analyzer, importCallback func(string) error) (findings []Finding, factData []byte, err error) {
- imp := &importer{
- PackageConfig: config,
- fset: token.NewFileSet(),
- cache: make(map[string]*types.Package),
- callback: importCallback,
- }
-
- // Load all source files.
- var syntax []*ast.File
- for _, file := range config.GoFiles {
- include, err := config.shouldInclude(file)
- if err != nil {
- return nil, 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, 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),
- }
- astTypes, err := typeConfig.Check(config.ImportPath, imp.fset, syntax, typesInfo)
- if err != nil && imp.lastErr != ErrSkip {
- return nil, nil, fmt.Errorf("error checking types: %w", err)
- }
-
- // Load all facts using the astTypes, although it may need reconciling
- // later on. See the fact functions below.
- astFacts, err := facts.Decode(astTypes, config.factLoader)
- if err != nil {
- return nil, nil, fmt.Errorf("error decoding facts: %w", err)
- }
-
- // Sanity check all types and record metadata to prevent
- // https://github.com/golang/go/issues/44195.
- //
- // This block loads the binary types, whose encoding will be well
- // defined and aligned with any downstream consumers. Below in the fact
- // functions for the analysis, we serialize types to both the astFacts
- // and the binaryFacts if available. The binaryFacts are the final
- // encoded facts in order to ensure compatibility. We keep the
- // intermediate astTypes in order to allow exporting and importing
- // within the local package under analysis.
- var (
- astToBinary = make(map[types.Object]types.Object)
- binaryFacts *facts.Set
- )
- if _, ok := config.ImportMap[config.ImportPath]; ok {
- binaryTypes, err := imp.Import(config.ImportPath)
- if err != nil {
- return nil, nil, fmt.Errorf("error loading self: %w", err)
- }
- if err := sanityCheckTypes(astTypes, binaryTypes, astToBinary); err != nil {
- return nil, nil, fmt.Errorf("error sanity checking types: %w", err)
- }
- binaryFacts, err = facts.Decode(binaryTypes, config.factLoader)
- if err != nil {
- return nil, nil, fmt.Errorf("error decoding facts: %w", err)
- }
- }
-
- // Register fact types and establish dependencies between analyzers.
- // The visit closure will execute recursively, and populate results
- // will all required analysis results.
- 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
- }
- }
-
- // Run the analysis.
- localFactsFilter := make(map[reflect.Type]bool)
- for _, f := range a.FactTypes {
- localFactsFilter[reflect.TypeOf(f)] = true
- }
- p := &analysis.Pass{
- Analyzer: a,
- Fset: imp.fset,
- Files: syntax,
- Pkg: astTypes,
- TypesInfo: typesInfo,
- ResultOf: results, // All results.
- Report: func(d analysis.Diagnostic) {
- findings = append(findings, Finding{
- Category: AnalyzerName(a.Name),
- Position: imp.fset.Position(d.Pos),
- Message: d.Message,
- })
- },
- ImportPackageFact: astFacts.ImportPackageFact,
- ExportPackageFact: func(fact analysis.Fact) {
- astFacts.ExportPackageFact(fact)
- if binaryFacts != nil {
- binaryFacts.ExportPackageFact(fact)
- }
- },
- ImportObjectFact: astFacts.ImportObjectFact,
- ExportObjectFact: func(obj types.Object, fact analysis.Fact) {
- astFacts.ExportObjectFact(obj, fact)
- // Note that if no object is recorded in
- // astToBinary and binaryFacts != nil, then the
- // object doesn't appear in the exported data.
- // It was likely an internal object to the
- // package, and there is no meaningful
- // downstream consumer of the fact.
- if binaryObj, ok := astToBinary[obj]; ok && binaryFacts != nil {
- binaryFacts.ExportObjectFact(binaryObj, fact)
- }
- },
- AllPackageFacts: func() []analysis.PackageFact { return astFacts.AllPackageFacts(localFactsFilter) },
- AllObjectFacts: func() []analysis.ObjectFact { return astFacts.AllObjectFacts(localFactsFilter) },
- 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 analyzers recursively.
- for _, a := range analyzers {
- if imp.lastErr == ErrSkip {
- continue // No local analysis.
- }
- if err := visit(a); err != nil {
- return nil, nil, err // Already has context.
- }
- }
-
- // Return all findings. Note that we have a preference to returning the
- // binary facts if available, so that downstream consumers of these
- // facts will find the export aligns with the internal type details.
- // See the block above with the call to sanityCheckTypes.
- if binaryFacts != nil {
- return findings, binaryFacts.Encode(), nil
- }
- return findings, astFacts.Encode(), nil
-}
-
-func init() {
- gob.Register((*stdlibFact)(nil))
-}
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