Simplify analyzer and command line interface

The analyzer now only handles packages rather than one off files. This
simplifies the CLI functionality significantly.

analyzer.go

@@ -12,17 +12,15 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-// Package core holds the central scanning logic used by GAS
+// Package gas holds the central scanning logic used by GAS
 package gas
 
 import (
 	"go/ast"
-	"go/importer"
+	"go/build"
-	"go/parser"
 	"go/token"
 	"go/types"
 	"log"
-	"os"
 	"path"
 	"reflect"
 	"strings"
@@ -30,21 +28,6 @@ import (
 	"golang.org/x/tools/go/loader"
 )
 
-// ImportInfo is used to track aliased and initialization only imports.
-type ImportInfo struct {
-	Imported map[string]string
-	Aliased  map[string]string
-	InitOnly map[string]bool
-}
-
-func NewImportInfo() *ImportInfo {
-	return &ImportInfo{
-		make(map[string]string),
-		make(map[string]string),
-		make(map[string]bool),
-	}
-}
-
 // The Context is populated with data parsed from the source code as it is scanned.
 // It is passed through to all rule functions as they are called. Rules may use
 // this data in conjunction withe the encoutered AST node.
@@ -55,19 +38,9 @@ type Context struct {
 	Pkg      *types.Package
 	Root     *ast.File
 	Config   map[string]interface{}
-	Imports  *ImportInfo
+	Imports  *ImportTracker
 }
 
-// The Rule interface used by all rules supported by GAS.
-type Rule interface {
-	Match(ast.Node, *Context) (*Issue, error)
-}
-
-// A RuleSet maps lists of rules to the type of AST node they should be run on.
-// The anaylzer will only invoke rules contained in the list associated with the
-// type of AST node it is currently visiting.
-type RuleSet map[reflect.Type][]Rule
-
 // Metrics used when reporting information about a scanning run.
 type Metrics struct {
 	NumFiles int `json:"files"`
@@ -84,134 +57,81 @@ type Analyzer struct {
 	context     *Context
 	config      Config
 	logger      *log.Logger
-	Issues      []*Issue `json:"issues"`
+	issues      []*Issue
-	Stats       *Metrics `json:"metrics"`
+	stats       *Metrics
 }
 
 // NewAnalyzer builds a new anaylzer.
-func NewAnalyzer(conf Config, logger *log.Logger) Analyzer {
+func NewAnalyzer(conf Config, logger *log.Logger) *Analyzer {
-	if logger == nil {
-		logger = log.New(os.Stdout, "[gas]", 0)
-	}
 	ignoreNoSec := false
 	if val, err := conf.Get("ignoreNoSec"); err == nil {
 		if override, ok := val.(bool); ok {
 			ignoreNoSec = override
 		}
 	}
-	a := Analyzer{
+	return &Analyzer{
 		ignoreNosec: ignoreNoSec,
 		ruleset:     make(RuleSet),
 		context:     &Context{},
 		config:      conf,
 		logger:      logger,
-		Issues:      make([]*Issue, 0, 16),
+		issues:      make([]*Issue, 0, 16),
-		Stats:       &Metrics{0, 0, 0, 0},
+		stats:       &Metrics{},
-	}
-
-	return a
-}
-
-func (gas *Analyzer) process(filename string, source interface{}) error {
-	mode := parser.ParseComments
-	gas.context.FileSet = token.NewFileSet()
-	root, err := parser.ParseFile(gas.context.FileSet, filename, source, mode)
-	if err == nil {
-		gas.context.Config = gas.config
-		gas.context.Comments = ast.NewCommentMap(gas.context.FileSet, root, root.Comments)
-		gas.context.Root = root
-
-		// here we get type info
-		gas.context.Info = &types.Info{
-			Types:      make(map[ast.Expr]types.TypeAndValue),
-			Defs:       make(map[*ast.Ident]types.Object),
-			Uses:       make(map[*ast.Ident]types.Object),
-			Selections: make(map[*ast.SelectorExpr]*types.Selection),
-			Scopes:     make(map[ast.Node]*types.Scope),
-			Implicits:  make(map[ast.Node]types.Object),
-		}
-
-		conf := types.Config{Importer: importer.Default()}
-		gas.context.Pkg, err = conf.Check("pkg", gas.context.FileSet, []*ast.File{root}, gas.context.Info)
-		if err != nil {
-			// TODO(gm) Type checker not currently considering all files within a package
-			// see: issue #113
-			gas.logger.Printf(`Error during type checking: "%s"`, err)
-			err = nil
-		}
-
-		gas.context.Imports = NewImportInfo()
-		for _, pkg := range gas.context.Pkg.Imports() {
-			gas.context.Imports.Imported[pkg.Path()] = pkg.Name()
-		}
-		ast.Walk(gas, root)
-		gas.Stats.NumFiles++
-	}
-	return err
-}
-
-// AddRule adds a rule into a rule set list mapped to the given AST node's type.
-// The node is only needed for its type and is not otherwise used.
-func (gas *Analyzer) AddRule(r Rule, nodes []ast.Node) {
-	for _, n := range nodes {
-		t := reflect.TypeOf(n)
-		if val, ok := gas.ruleset[t]; ok {
-			gas.ruleset[t] = append(val, r)
-		} else {
-			gas.ruleset[t] = []Rule{r}
-		}
 	}
 }
 
-// Process reads in a source file, convert it to an AST and traverse it.
+func (gas *Analyzer) LoadRules(ruleDefinitions ...RuleBuilder) {
-// Rule methods added with AddRule will be invoked as necessary.
+	for _, builder := range ruleDefinitions {
-func (gas *Analyzer) Process(filename string) error {
+		r, nodes := builder(gas.config)
-	err := gas.process(filename, nil)
+		gas.ruleset.Register(r, nodes...)
-	fun := func(f *token.File) bool {
-		gas.Stats.NumLines += f.LineCount()
-		return true
 	}
-	gas.context.FileSet.Iterate(fun)
-	return err
 }
 
-func (gas *Analyzer) ProcessPackage(prog *loader.Program, pkg *loader.PackageInfo, file *ast.File) error {
+func (gas *Analyzer) Process(packagePath string) error {
 
-	gas.context.FileSet = prog.Fset
+	basePackage, err := build.Default.ImportDir(packagePath, build.ImportComment)
-	gas.context.Config = gas.config
+	if err != nil {
-	gas.context.Comments = ast.NewCommentMap(gas.context.FileSet, file, file.Comments)
+		return err
-	gas.context.Root = file
+	}
-	gas.context.Info = &pkg.Info
+
-	gas.context.Pkg = pkg.Pkg
+	packageConfig := loader.Config{Build: &build.Default}
-	gas.context.Imports = NewImportInfo()
+	packageFiles := make([]string, 0)
-	for _, imported := range gas.context.Pkg.Imports() {
+	for _, filename := range basePackage.GoFiles {
-		gas.context.Imports.Imported[imported.Path()] = imported.Name()
+		packageFiles = append(packageFiles, path.Join(packagePath, filename))
+	}
+
+	packageConfig.CreateFromFilenames(basePackage.Name, packageFiles...)
+	builtPackage, err := packageConfig.Load()
+	if err != nil {
+		return err
+	}
+
+	for _, pkg := range builtPackage.Created {
+		gas.logger.Println("Checking package:", pkg.String())
+		for _, file := range pkg.Files {
+			gas.logger.Println("Checking file:", builtPackage.Fset.File(file.Pos()).Name())
+			gas.context.FileSet = builtPackage.Fset
+			gas.context.Config = gas.config
+			gas.context.Comments = ast.NewCommentMap(gas.context.FileSet, file, file.Comments)
+			gas.context.Root = file
+			gas.context.Info = &pkg.Info
+			gas.context.Pkg = pkg.Pkg
+			gas.context.Imports = NewImportTracker()
+			gas.context.Imports.TrackPackages(gas.context.Pkg.Imports()...)
+			ast.Walk(gas, file)
+			gas.stats.NumFiles++
+			gas.stats.NumLines += builtPackage.Fset.File(file.Pos()).LineCount()
+		}
 	}
-	ast.Walk(gas, file)
-	gas.Stats.NumFiles++
-	gas.Stats.NumLines += prog.Fset.File(file.Pos()).LineCount()
 	return nil
 }
 
-// ProcessSource will convert a source code string into an AST and traverse it.
-// Rule methods added with AddRule will be invoked as necessary. The string is
-// identified by the filename given but no file IO will be done.
-func (gas *Analyzer) ProcessSource(filename string, source string) error {
-	err := gas.process(filename, source)
-	fun := func(f *token.File) bool {
-		gas.Stats.NumLines += f.LineCount()
-		return true
-	}
-	gas.context.FileSet.Iterate(fun)
-	return err
-}
-
 // ignore a node (and sub-tree) if it is tagged with a "#nosec" comment
 func (gas *Analyzer) ignore(n ast.Node) bool {
 	if groups, ok := gas.context.Comments[n]; ok && !gas.ignoreNosec {
 		for _, group := range groups {
 			if strings.Contains(group.Text(), "#nosec") {
-				gas.Stats.NumNosec++
+				gas.stats.NumNosec++
 				return true
 			}
 		}
@@ -225,38 +145,26 @@ func (gas *Analyzer) Visit(n ast.Node) ast.Visitor {
 	if !gas.ignore(n) {
 
 		// Track aliased and initialization imports
-		if imported, ok := n.(*ast.ImportSpec); ok {
+		gas.context.Imports.TrackImport(n)
-			path := strings.Trim(imported.Path.Value, `"`)
-			if imported.Name != nil {
-				if imported.Name.Name == "_" {
-					// Initialization import
-					gas.context.Imports.InitOnly[path] = true
-				} else {
-					// Aliased import
-					gas.context.Imports.Aliased[path] = imported.Name.Name
-				}
-			}
-			// unsafe is not included in Package.Imports()
-			if path == "unsafe" {
-				gas.context.Imports.Imported[path] = path
-			}
-		}
 
-		if val, ok := gas.ruleset[reflect.TypeOf(n)]; ok {
+		for _, rule := range gas.ruleset.RegisteredFor(n) {
-			for _, rule := range val {
+			issue, err := rule.Match(n, gas.context)
-				ret, err := rule.Match(n, gas.context)
+			if err != nil {
-				if err != nil {
+				file, line := GetLocation(n, gas.context)
-					file, line := GetLocation(n, gas.context)
+				file = path.Base(file)
-					file = path.Base(file)
+				gas.logger.Printf("Rule error: %v => %s (%s:%d)\n", reflect.TypeOf(rule), err, file, line)
-					gas.logger.Printf("Rule error: %v => %s (%s:%d)\n", reflect.TypeOf(rule), err, file, line)
+			}
-				}
+			if issue != nil {
-				if ret != nil {
+				gas.issues = append(gas.issues, issue)
-					gas.Issues = append(gas.Issues, ret)
+				gas.stats.NumFound++
-					gas.Stats.NumFound++
-				}
 			}
 		}
 		return gas
 	}
 	return nil
 }
+
+// Report returns the current issues discovered and the metrics about the scan
+func (gas *Analyzer) Report() ([]*Issue, *Metrics) {
+	return gas.issues, gas.stats
+}

cmd/gas/main.go

@@ -15,47 +15,22 @@
 package main
 
 import (
-	"encoding/json"
 	"flag"
 	"fmt"
-	"go/build"
-	"io/ioutil"
 	"log"
 	"os"
-	"path"
 	"path/filepath"
+	"regexp"
 	"sort"
 	"strings"
 
 	"github.com/GoASTScanner/gas"
 	"github.com/GoASTScanner/gas/output"
 	"github.com/GoASTScanner/gas/rules"
-	"golang.org/x/tools/go/loader"
+	"github.com/kisielk/gotool"
 )
 
-type recursion bool
-
 const (
-	recurse   recursion = true
-	noRecurse recursion = false
-)
-
-var (
-	// #nosec flag
-	flagIgnoreNoSec = flag.Bool("nosec", false, "Ignores #nosec comments when set")
-
-	// format output
-	flagFormat = flag.String("fmt", "text", "Set output format. Valid options are: json, csv, html, or text")
-
-	// output file
-	flagOutput = flag.String("out", "", "Set output file for results")
-
-	// config file
-	flagConfig = flag.String("conf", "", "Path to optional config file")
-
-	// quiet
-	flagQuiet = flag.Bool("quiet", false, "Only show output when errors are found")
-
 	usageText = `
 GAS - Go AST Scanner
 
@@ -78,58 +53,36 @@ USAGE:
 	$ gas -exclude=G101 ./...
 
 `
+)
+
+var (
+	// #nosec flag
+	flagIgnoreNoSec = flag.Bool("nosec", false, "Ignores #nosec comments when set")
+
+	// format output
+	flagFormat = flag.String("fmt", "text", "Set output format. Valid options are: json, csv, html, or text")
+
+	// output file
+	flagOutput = flag.String("out", "", "Set output file for results")
+
+	// config file
+	flagConfig = flag.String("conf", "", "Path to optional config file")
+
+	// quiet
+	flagQuiet = flag.Bool("quiet", false, "Only show output when errors are found")
+
+	// rules to explicitly include
+	flagRulesInclude = flag.String("include", "", "Comma separated list of rules IDs to include. (see rule list)")
+
+	// rules to explicitly exclude
+	flagRulesExclude = flag.String("exclude", "", "Comma separated list of rules IDs to exclude. (see rule list)")
+
+	// log to file or stderr
+	flagLogfile = flag.String("log", "", "Log messages to file rather than stderr")
 
 	logger *log.Logger
 )
 
-func extendConfList(conf map[string]interface{}, name string, inputStr string) {
-	if inputStr == "" {
-		conf[name] = []string{}
-	} else {
-		input := strings.Split(inputStr, ",")
-		if val, ok := conf[name]; ok {
-			if data, ok := val.(*[]string); ok {
-				conf[name] = append(*data, input...)
-			} else {
-				logger.Fatal("Config item must be a string list: ", name)
-			}
-		} else {
-			conf[name] = input
-		}
-	}
-}
-
-func buildConfig(incRules string, excRules string) map[string]interface{} {
-	config := make(map[string]interface{})
-	if flagConfig != nil && *flagConfig != "" { // parse config if we have one
-		if data, err := ioutil.ReadFile(*flagConfig); err == nil {
-			if err := json.Unmarshal(data, &(config)); err != nil {
-				logger.Fatal("Could not parse JSON config: ", *flagConfig, ": ", err)
-			}
-		} else {
-			logger.Fatal("Could not read config file: ", *flagConfig)
-		}
-	}
-
-	// add in CLI include and exclude data
-	extendConfList(config, "include", incRules)
-	extendConfList(config, "exclude", excRules)
-
-	// override ignoreNosec if given on CLI
-	if flagIgnoreNoSec != nil {
-		config["ignoreNosec"] = *flagIgnoreNoSec
-	} else {
-		val, ok := config["ignoreNosec"]
-		if !ok {
-			config["ignoreNosec"] = false
-		} else if _, ok := val.(bool); !ok {
-			logger.Fatal("Config value must be a bool: 'ignoreNosec'")
-		}
-	}
-
-	return config
-}
-
 // #nosec
 func usage() {
 
@@ -152,43 +105,47 @@ func usage() {
 	fmt.Fprint(os.Stderr, "\n")
 }
 
-// TODO(gm) This needs to be refactored (potentially included in Analyzer)
+func loadConfig(configFile string) (gas.Config, error) {
-func analyzePackage(packageDirectory string, metrics *gas.Metrics, config gas.Config, logger *log.Logger, ruleDefs rules.RuleList) ([]*gas.Issue, error) {
+	config := gas.NewConfig()
-
+	if configFile != "" {
-	basePackage, err := build.Default.ImportDir(packageDirectory, build.ImportComment)
+		file, err := os.Open(configFile)
-	if err != nil {
+		if err != nil {
-		return nil, err
+			return nil, err
-	}
-
-	packageConfig := loader.Config{Build: &build.Default}
-	packageFiles := make([]string, 0)
-	for _, filename := range basePackage.GoFiles {
-		packageFiles = append(packageFiles, path.Join(packageDirectory, filename))
-	}
-
-	packageConfig.CreateFromFilenames(basePackage.Name, packageFiles...)
-	builtPackage, err := packageConfig.Load()
-	if err != nil {
-		return nil, err
-	}
-	issues := make([]*gas.Issue, 0)
-
-	for _, pkg := range builtPackage.Created {
-		analyzer := gas.NewAnalyzer(config, logger)
-		for _, rule := range ruleDefs {
-			analyzer.AddRule(rule.Create(config))
 		}
-		for _, file := range pkg.Files {
+		defer file.Close()
-			analyzer.ProcessPackage(builtPackage, pkg, file)
+		if _, err := config.ReadFrom(file); err != nil {
+			return nil, err
 		}
-		issues = append(issues, analyzer.Issues...)
+	}
-		metrics.NumFiles += analyzer.Stats.NumFiles
+	return config, nil
-		metrics.NumFound += analyzer.Stats.NumFound
+}
-		metrics.NumLines += analyzer.Stats.NumLines
+
-		metrics.NumNosec += analyzer.Stats.NumNosec
+func loadRules(include, exclude string) rules.RuleList {
+	filters := make([]rules.RuleFilter, 0)
+	if include != "" {
+		including := strings.Split(include, ",")
+		filters = append(filters, rules.NewRuleFilter(false, including...))
 	}
 
-	return issues, nil
+	if exclude != "" {
+		excluding := strings.Split(exclude, ",")
+		filters = append(filters, rules.NewRuleFilter(true, excluding...))
+	}
+	return rules.Generate(filters...)
+}
+
+func saveOutput(filename, format string, issues []*gas.Issue, metrics *gas.Metrics) error {
+	if filename != "" {
+		outfile, err := os.Create(filename)
+		if err != nil {
+			return err
+		}
+		defer outfile.Close()
+		output.CreateReport(outfile, format, issues, metrics)
+	} else {
+		output.CreateReport(os.Stdout, format, issues, metrics)
+	}
+	return nil
 }
 
 func main() {
@@ -200,93 +157,61 @@ func main() {
 	excluded := newFileList("*_test.go")
 	flag.Var(excluded, "skip", "File pattern to exclude from scan. Uses simple * globs and requires full or partial match")
 
-	incRules := ""
-	flag.StringVar(&incRules, "include", "", "Comma separated list of rules IDs to include. (see rule list)")
-
-	excRules := ""
-	flag.StringVar(&excRules, "exclude", "", "Comma separated list of rules IDs to exclude. (see rule list)")
-
-	// Custom commands / utilities to run instead of default analyzer
-	tools := newUtils()
-	flag.Var(tools, "tool", "GAS utilities to assist with rule development")
-
-	// Setup logging
-	logger = log.New(os.Stderr, "[gas] ", log.LstdFlags)
-
 	// Parse command line arguments
 	flag.Parse()
 
 	// Ensure at least one file was specified
 	if flag.NArg() == 0 {
-
 		fmt.Fprintf(os.Stderr, "\nError: FILE [FILE...] or './...' expected\n")
 		flag.Usage()
 		os.Exit(1)
 	}
 
-	// Run utils instead of analysis
+	// Setup logging
-	if len(tools.call) > 0 {
+	logWriter := os.Stderr
-		tools.run(flag.Args()...)
+	if *flagLogfile != "" {
-		os.Exit(0)
+		var e error
+		logWriter, e = os.Create(*flagLogfile)
+		if e != nil {
+			flag.Usage()
+			log.Fatal(e)
+		}
 	}
+	logger = log.New(logWriter, "[gas] ", log.LstdFlags)
 
 	// Load config
-	config := gas.NewConfig()
+	config, err := loadConfig(*flagConfig)
-	if flagConfig != nil && *flagConfig != "" {
+	if err != nil {
-		file, err := os.Open(*flagConfig)
+		logger.Fatal(err)
-		if err != nil {
-			logger.Fatal(err)
-		}
-		defer file.Close()
-		if _, err := config.ReadFrom(file); err != nil {
-			logger.Fatal(err)
-		}
 	}
-	filters := make([]rules.RuleFilter, 0)
-	if incRules != "" {
-		including := strings.Split(incRules, ",")
-		filters = append(filters, rules.NewRuleFilter(false, including...))
-	}
-	if excRules != "" {
-		excluding := strings.Split(excRules, ",")
-		filters = append(filters, rules.NewRuleFilter(true, excluding...))
-	}
-	ruleDefinitions := rules.Generate(filters...)
-	issues := make([]*gas.Issue, 0)
-	metrics := &gas.Metrics{}
-	for _, arg := range flag.Args() {
-		if arg == "./..." {
-			baseDirectory, err := os.Getwd()
-			if err != nil {
-				log.Fatal(err)
-			}
 
-			filepath.Walk(baseDirectory, func(path string, finfo os.FileInfo, e error) error {
+	// Load enabled rule definitions
-				dir := filepath.Base(path)
+	ruleDefinitions := loadRules(*flagRulesInclude, *flagRulesExclude)
-				if finfo.IsDir() {
+
-					// TODO(gm) - This...
+	// Create the analyzer
-					if strings.HasPrefix(dir, ".") || dir == "vendor" || dir == "GoDeps" {
+	analyzer := gas.NewAnalyzer(config, logger)
-						log.Printf("Skipping %s\n", path)
+	analyzer.LoadRules(ruleDefinitions.Builders()...)
-						return filepath.SkipDir
+
-					}
+	vendor := regexp.MustCompile(`[\\/]vendor([\\/]|$)`)
-					newIssues, err := analyzePackage(path, metrics, config, logger, ruleDefinitions)
+
-					if err != nil {
+	// Iterate over packages on the import paths
-						log.Println(err)
+	for _, pkg := range gotool.ImportPaths(flag.Args()) {
-					} else {
+
-						issues = append(issues, newIssues...)
+		// Skip vendor directory
-					}
+		if vendor.MatchString(pkg) {
-				}
+			continue
-				return nil
+		}
-			})
+
-		} else {
+		abspath, _ := filepath.Abs(pkg)
-			newIssues, err := analyzePackage(arg, metrics, config, logger, ruleDefinitions)
+		logger.Println("Searching directory:", abspath)
-			if err != nil {
+		if err := analyzer.Process(pkg); err != nil {
-				log.Fatal(err)
+			logger.Fatal(err)
-			}
-			issues = newIssues
 		}
 	}
 
+	// Collect the results
+	issues, metrics := analyzer.Report()
+
 	issuesFound := len(issues) > 0
 	// Exit quietly if nothing was found
 	if !issuesFound && *flagQuiet {
@@ -294,17 +219,13 @@ func main() {
 	}
 
 	// Create output report
-	if *flagOutput != "" {
+	if err := saveOutput(*flagOutput, *flagFormat, issues, metrics); err != nil {
-		outfile, err := os.Create(*flagOutput)
+		logger.Fatal(err)
-		if err != nil {
-			logger.Fatalf("Couldn't open: %s for writing. Reason - %s", *flagOutput, err)
-		}
-		defer outfile.Close()
-		output.CreateReport(outfile, *flagFormat, issues, metrics)
-	} else {
-		output.CreateReport(os.Stdout, *flagFormat, issues, metrics)
 	}
 
+	// Finialize logging
+	logWriter.Close()
+
 	// Do we have an issue? If so exit 1
 	if issuesFound {
 		os.Exit(1)