pkg: handle gosimple linter findings (#322)

This change is an attempt to handle gosimple linter finfings in order to
make the code easier to follow. It includes the following changes:

- use strings.Contains instead of strings.Index != -1
- use time.Since which is the standard library helper. See https://github.com/golang/go/blob/go1.15.2/src/time/time.go#L866-L867
- remove unneeded return statements at the end of methods
- preallocate maps when their capacity is known
- avoid underscoring values when they can be omitted
- avoid fmt.Sprintf() calls when the only argument is already a string

Signed-off-by: Miguel Ángel Jimeno <miguelangel4b@gmail.com>

pkg/ffuf/job.go

@@ -123,10 +123,7 @@ func (j *Job) Start() {
 }
 
 func (j *Job) jobsInQueue() bool {
-	if j.queuepos < len(j.queuejobs) {
-		return true
-	}
-	return false
+	return j.queuepos < len(j.queuejobs)
 }
 
 func (j *Job) prepareQueueJob() {
@@ -192,14 +189,13 @@ func (j *Job) startExecution() {
 	}
 	wg.Wait()
 	j.updateProgress()
-	return
 }
 
 func (j *Job) interruptMonitor() {
 	sigChan := make(chan os.Signal, 2)
 	signal.Notify(sigChan, os.Interrupt, syscall.SIGTERM)
 	go func() {
-		for _ = range sigChan {
+		for range sigChan {
 			j.Error = "Caught keyboard interrupt (Ctrl-C)\n"
 			j.Stop()
 		}
@@ -321,7 +317,6 @@ func (j *Job) runTask(input map[string][]byte, position int, retried bool) {
 	if j.Config.Recursion && len(resp.GetRedirectLocation(false)) > 0 {
 		j.handleRecursionJob(resp)
 	}
-	return
 }
 
 //handleRecursionJob adds a new recursion job to the job queue if a new directory is found
@@ -356,7 +351,7 @@ func (j *Job) CalibrateResponses() ([]Response, error) {
 
 	results := make([]Response, 0)
 	for _, input := range cInputs {
-		inputs := make(map[string][]byte, 0)
+		inputs := make(map[string][]byte, len(j.Config.InputProviders))
 		for _, v := range j.Config.InputProviders {
 			inputs[v.Keyword] = []byte(input)
 		}
@@ -409,7 +404,7 @@ func (j *Job) CheckStop() {
 
 	// Check for runtime of entire process
 	if j.Config.MaxTime > 0 {
-		dur := time.Now().Sub(j.startTime)
+		dur := time.Since(j.startTime)
 		runningSecs := int(dur / time.Second)
 		if runningSecs >= j.Config.MaxTime {
 			j.Error = "Maximum running time for entire process reached, exiting."
@@ -419,7 +414,7 @@ func (j *Job) CheckStop() {
 
 	// Check for runtime of current job
 	if j.Config.MaxTimeJob > 0 {
-		dur := time.Now().Sub(j.startTimeJob)
+		dur := time.Since(j.startTimeJob)
 		runningSecs := int(dur / time.Second)
 		if runningSecs >= j.Config.MaxTimeJob {
 			j.Error = "Maximum running time for this job reached, continuing with next job if one exists."
@@ -433,11 +428,9 @@ func (j *Job) CheckStop() {
 func (j *Job) Stop() {
 	j.Running = false
 	j.Config.Cancel()
-	return
 }
 
 //Stop current, resume to next
 func (j *Job) Next() {
 	j.RunningJob = false
-	return
 }

pkg/ffuf/optionsparser.go

@@ -387,7 +387,7 @@ func ConfigFromOptions(parseOpts *ConfigOptions, ctx context.Context, cancel con
 	// Do checks for recursion mode
 	if parseOpts.HTTP.Recursion {
 		if !strings.HasSuffix(conf.Url, "FUZZ") {
-			errmsg := fmt.Sprintf("When using -recursion the URL (-u) must end with FUZZ keyword.")
+			errmsg := "When using -recursion the URL (-u) must end with FUZZ keyword."
 			errs.Add(fmt.Errorf(errmsg))
 		}
 	}
@@ -460,20 +460,20 @@ func parseRawRequest(parseOpts *ConfigOptions, conf *Config) error {
 
 func keywordPresent(keyword string, conf *Config) bool {
 	//Search for keyword from HTTP method, URL and POST data too
-	if strings.Index(conf.Method, keyword) != -1 {
+	if strings.Contains(conf.Method, keyword) {
 		return true
 	}
-	if strings.Index(conf.Url, keyword) != -1 {
+	if strings.Contains(conf.Url, keyword) {
 		return true
 	}
-	if strings.Index(conf.Data, keyword) != -1 {
+	if strings.Contains(conf.Data, keyword) {
 		return true
 	}
 	for k, v := range conf.Headers {
-		if strings.Index(k, keyword) != -1 {
+		if strings.Contains(k, keyword) {
 			return true
 		}
-		if strings.Index(v, keyword) != -1 {
+		if strings.Contains(v, keyword) {
 			return true
 		}
 	}

pkg/ffuf/util.go

@@ -25,7 +25,7 @@ func UniqStringSlice(inslice []string) []string {
 		found[v] = true
 	}
 	ret := []string{}
-	for k, _ := range found {
+	for k := range found {
 		ret = append(ret, k)
 	}
 	return ret

pkg/filter/lines_test.go

@@ -10,7 +10,7 @@ import (
 func TestNewLineFilter(t *testing.T) {
 	f, _ := NewLineFilter("200,301,400-410,500")
 	linesRepr := f.Repr()
-	if strings.Index(linesRepr, "200,301,400-410,500") == -1 {
+	if !strings.Contains(linesRepr, "200,301,400-410,500") {
 		t.Errorf("Word filter was expected to have 4 values")
 	}
 }

pkg/filter/regexp_test.go

@@ -10,7 +10,7 @@ import (
 func TestNewRegexpFilter(t *testing.T) {
 	f, _ := NewRegexpFilter("s([a-z]+)arch")
 	statusRepr := f.Repr()
-	if strings.Index(statusRepr, "s([a-z]+)arch") == -1 {
+	if !strings.Contains(statusRepr, "s([a-z]+)arch") {
 		t.Errorf("Status filter was expected to have a regexp value")
 	}
 }

pkg/filter/size_test.go

@@ -10,7 +10,7 @@ import (
 func TestNewSizeFilter(t *testing.T) {
 	f, _ := NewSizeFilter("1,2,3,444,5-90")
 	sizeRepr := f.Repr()
-	if strings.Index(sizeRepr, "1,2,3,444,5-90") == -1 {
+	if !strings.Contains(sizeRepr, "1,2,3,444,5-90") {
 		t.Errorf("Size filter was expected to have 5 values")
 	}
 }

pkg/filter/status_test.go

@@ -10,7 +10,7 @@ import (
 func TestNewStatusFilter(t *testing.T) {
 	f, _ := NewStatusFilter("200,301,400-410,500")
 	statusRepr := f.Repr()
-	if strings.Index(statusRepr, "200,301,400-410,500") == -1 {
+	if !strings.Contains(statusRepr, "200,301,400-410,500") {
 		t.Errorf("Status filter was expected to have 4 values")
 	}
 }

pkg/filter/words_test.go

@@ -10,7 +10,7 @@ import (
 func TestNewWordFilter(t *testing.T) {
 	f, _ := NewWordFilter("200,301,400-410,500")
 	wordsRepr := f.Repr()
-	if strings.Index(wordsRepr, "200,301,400-410,500") == -1 {
+	if !strings.Contains(wordsRepr, "200,301,400-410,500") {
 		t.Errorf("Word filter was expected to have 4 values")
 	}
 }

pkg/input/command.go

@@ -47,10 +47,7 @@ func (c *CommandInput) IncrementPosition() {
 
 //Next will increment the cursor position, and return a boolean telling if there's iterations left
 func (c *CommandInput) Next() bool {
-	if c.count >= c.config.InputNum {
-		return false
-	}
-	return true
+	return c.count < c.config.InputNum
 }
 
 //Value returns the input from command stdoutput

pkg/input/wordlist.go

@@ -57,10 +57,7 @@ func (w *WordlistInput) Keyword() string {
 
 //Next will increment the cursor position, and return a boolean telling if there's words left in the list
 func (w *WordlistInput) Next() bool {
-	if w.position >= len(w.data) {
-		return false
-	}
-	return true
+	return w.position < len(w.data)
 }
 
 //IncrementPosition will increment the current position in the inputprovider data slice

pkg/output/file_csv.go

@@ -25,17 +25,14 @@ func writeCSV(config *ffuf.Config, res []Result, encode bool) error {
 	for _, inputprovider := range config.InputProviders {
 		header = append(header, inputprovider.Keyword)
 	}
-
-	for _, item := range staticheaders {
-		header = append(header, item)
-	}
+	header = append(header, staticheaders...)
 
 	if err := w.Write(header); err != nil {
 		return err
 	}
 	for _, r := range res {
 		if encode {
-			inputs := make(map[string][]byte, 0)
+			inputs := make(map[string][]byte, len(r.Input))
 			for k, v := range r.Input {
 				inputs[k] = []byte(base64encode(v))
 			}

pkg/output/stdout.go

@@ -107,12 +107,10 @@ func (s *Stdoutput) Banner() error {
 
 	// Proxies
 	if len(s.config.ProxyURL) > 0 {
-		proxy := fmt.Sprintf("%s", s.config.ProxyURL)
-		printOption([]byte("Proxy"), []byte(proxy))
+		printOption([]byte("Proxy"), []byte(s.config.ProxyURL))
 	}
 	if len(s.config.ReplayProxyURL) > 0 {
-		replayproxy := fmt.Sprintf("%s", s.config.ReplayProxyURL)
-		printOption([]byte("ReplayProxy"), []byte(replayproxy))
+		printOption([]byte("ReplayProxy"), []byte(s.config.ReplayProxyURL))
 	}
 
 	// Timeout
@@ -152,7 +150,7 @@ func (s *Stdoutput) Progress(status ffuf.Progress) {
 		return
 	}
 
-	dur := time.Now().Sub(status.StartedAt)
+	dur := time.Since(status.StartedAt)
 	runningSecs := int(dur / time.Second)
 	var reqRate int64
 	if runningSecs > 0 {
@@ -289,7 +287,7 @@ func (s *Stdoutput) Result(resp ffuf.Response) {
 	// Check if we need the data later
 	if s.config.OutputFile != "" {
 		// No need to store results if we're not going to use them later
-		inputs := make(map[string][]byte, 0)
+		inputs := make(map[string][]byte, len(resp.Request.Input))
 		for k, v := range resp.Request.Input {
 			inputs[k] = v
 		}
@@ -404,14 +402,13 @@ func (s *Stdoutput) resultMultiline(resp ffuf.Response) {
 }
 
 func (s *Stdoutput) resultNormal(resp ffuf.Response) {
-	var res_str string
-	res_str = fmt.Sprintf("%s%-23s [Status: %s, Size: %d, Words: %d, Lines: %d]", TERMINAL_CLEAR_LINE, s.prepareInputsOneLine(resp), s.colorize(fmt.Sprintf("%d", resp.StatusCode), resp.StatusCode), resp.ContentLength, resp.ContentWords, resp.ContentLines)
-	fmt.Println(res_str)
+	res := fmt.Sprintf("%s%-23s [Status: %s, Size: %d, Words: %d, Lines: %d]", TERMINAL_CLEAR_LINE, s.prepareInputsOneLine(resp), s.colorize(fmt.Sprintf("%d", resp.StatusCode), resp.StatusCode), resp.ContentLength, resp.ContentWords, resp.ContentLines)
+	fmt.Println(res)
 }
 
 func (s *Stdoutput) colorize(input string, status int64) string {
 	if !s.config.Colors {
-		return fmt.Sprintf("%s", input)
+		return input
 	}
 	colorCode := ANSI_CLEAR
 	if status >= 200 && status < 300 {

pkg/runner/simple.go

@@ -78,7 +78,7 @@ func (r *SimpleRunner) Prepare(input map[string][]byte) (ffuf.Request, error) {
 
 	for keyword, inputitem := range input {
 		req.Method = strings.ReplaceAll(req.Method, keyword, string(inputitem))
-		headers := make(map[string]string, 0)
+		headers := make(map[string]string, len(req.Headers))
 		for h, v := range req.Headers {
 			var CanonicalHeader string = textproto.CanonicalMIMEHeaderKey(strings.ReplaceAll(h, keyword, string(inputitem)))
 			headers[CanonicalHeader] = strings.ReplaceAll(v, keyword, string(inputitem))