new: new caplets module to manage system caplets

caplets/env.go

@@ -8,8 +8,12 @@ import (
 )
 
 const (
-	Suffix      = ".cap"
+	EnvVarName         = "CAPSPATH"
-	InstallPath = "/usr/local/share/bettercap/caplets/"
+	Suffix             = ".cap"
+	InstallArchive     = "https://github.com/bettercap/caplets/archive/master.zip"
+	InstallBase        = "/usr/local/share/bettercap/"
+	InstallPathArchive = "/usr/local/share/bettercap/caplets-master/"
+	InstallPath        = "/usr/local/share/bettercap/caplets/"
 )
 
 var (
@@ -20,7 +24,7 @@ var (
 )
 
 func init() {
-	for _, path := range core.SepSplit(core.Trim(os.Getenv("CAPSPATH")), ":") {
+	for _, path := range core.SepSplit(core.Trim(os.Getenv(EnvVarName)), ":") {
 		if path = core.Trim(path); len(path) > 0 {
 			LoadPaths = append(LoadPaths, path)
 		}

caplets/manager.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"os"
 	"path/filepath"
+	"sort"
 	"strings"
 	"sync"
 
@@ -38,6 +39,10 @@ func List() []Caplet {
 		}
 	}
 
+	sort.Slice(caplets, func(i, j int) bool {
+		return strings.Compare(caplets[i].Name, caplets[j].Name) == -1
+	})
+
 	return caplets
 }
 

core/core.go

@@ -1,7 +1,9 @@
 package core
 
 import (
+	"archive/zip"
 	"fmt"
+	"io"
 	"os"
 	"os/exec"
 	"os/user"
@@ -102,3 +104,48 @@ func ExpandPath(path string) (string, error) {
 	}
 	return "", nil
 }
+
+// Unzip will decompress a zip archive, moving all files and folders
+// within the zip file (parameter 1) to an output directory (parameter 2).
+// Credits to https://golangcode.com/unzip-files-in-go/
+func Unzip(src string, dest string) ([]string, error) {
+	var filenames []string
+
+	r, err := zip.OpenReader(src)
+	if err != nil {
+		return filenames, err
+	}
+	defer r.Close()
+
+	for _, f := range r.File {
+		rc, err := f.Open()
+		if err != nil {
+			return filenames, err
+		}
+		defer rc.Close()
+
+		// Store filename/path for returning and using later on
+		fpath := filepath.Join(dest, f.Name)
+
+		// Check for ZipSlip. More Info: https://snyk.io/research/zip-slip-vulnerability#go
+		if !strings.HasPrefix(fpath, filepath.Clean(dest)+string(os.PathSeparator)) {
+			return filenames, fmt.Errorf("%s: illegal file path", fpath)
+		}
+
+		filenames = append(filenames, fpath)
+		if f.FileInfo().IsDir() {
+			os.MkdirAll(fpath, os.ModePerm)
+		} else if err = os.MkdirAll(filepath.Dir(fpath), os.ModePerm); err != nil {
+			return filenames, err
+		} else if outFile, err := os.OpenFile(fpath, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, f.Mode()); err != nil {
+			return filenames, err
+		} else {
+			defer outFile.Close()
+			if _, err = io.Copy(outFile, rc); err != nil {
+				return filenames, err
+			}
+		}
+	}
+
+	return filenames, nil
+}

main.go

@@ -35,6 +35,7 @@ func main() {
 	sess.Register(modules.NewEventsStream(sess))
 	sess.Register(modules.NewTicker(sess))
 	sess.Register(modules.NewUpdateModule(sess))
+	sess.Register(modules.NewCapletsModule(sess))
 	sess.Register(modules.NewMacChanger(sess))
 	sess.Register(modules.NewProber(sess))
 	sess.Register(modules.NewDiscovery(sess))

modules/caplets.go

@@ -0,0 +1,148 @@
+package modules
+
+import (
+	"fmt"
+	"io"
+	"net/http"
+	"os"
+
+	"github.com/bettercap/bettercap/caplets"
+	"github.com/bettercap/bettercap/core"
+	"github.com/bettercap/bettercap/log"
+	"github.com/bettercap/bettercap/session"
+
+	"github.com/dustin/go-humanize"
+)
+
+type CapletsModule struct {
+	session.SessionModule
+}
+
+func NewCapletsModule(s *session.Session) *CapletsModule {
+	c := &CapletsModule{
+		SessionModule: session.NewSessionModule("caplets", s),
+	}
+
+	c.AddHandler(session.NewModuleHandler("caplets.show", "",
+		"Show a list of installed caplets.",
+		func(args []string) error {
+			return c.Show()
+		}))
+
+	c.AddHandler(session.NewModuleHandler("caplets.paths", "",
+		"Show a list caplet search paths.",
+		func(args []string) error {
+			return c.Paths()
+		}))
+
+	c.AddHandler(session.NewModuleHandler("caplets.update", "",
+		"Install/updates the caplets.",
+		func(args []string) error {
+			return c.Update()
+		}))
+
+	return c
+}
+
+func (c *CapletsModule) Name() string {
+	return "caplets"
+}
+
+func (c *CapletsModule) Description() string {
+	return "A module to list and update caplets."
+}
+
+func (c *CapletsModule) Author() string {
+	return "Simone Margaritelli <evilsocket@protonmail.com>"
+}
+
+func (c *CapletsModule) Configure() error {
+	return nil
+}
+
+func (c *CapletsModule) Stop() error {
+	return nil
+}
+
+func (c *CapletsModule) Start() error {
+	return nil
+}
+
+func (c *CapletsModule) Show() error {
+	caplets := caplets.List()
+	if len(caplets) == 0 {
+		return fmt.Errorf("no installed caplets on this system, use the caplets.update command to download them")
+	}
+
+	colNames := []string{
+		"Name",
+		"Path",
+		"Size",
+	}
+	rows := [][]string{}
+
+	for _, caplet := range caplets {
+		rows = append(rows, []string{
+			core.Bold(caplet.Name),
+			caplet.Path,
+			core.Dim(humanize.Bytes(uint64(caplet.Size))),
+		})
+	}
+
+	core.AsTable(os.Stdout, colNames, rows)
+
+	return nil
+}
+
+func (c *CapletsModule) Paths() error {
+	colNames := []string{
+		"Path",
+	}
+	rows := [][]string{[]string{"."}}
+
+	for _, path := range caplets.LoadPaths {
+		rows = append(rows, []string{path})
+	}
+
+	core.AsTable(os.Stdout, colNames, rows)
+	fmt.Printf("(paths can be customized by defining the %s environment variable)\n", core.Bold(caplets.EnvVarName))
+
+	return nil
+}
+
+func (c *CapletsModule) Update() error {
+	if !core.Exists(caplets.InstallBase) {
+		log.Info("creating caplets install path %s ...", caplets.InstallBase)
+		if err := os.MkdirAll(caplets.InstallBase, os.ModePerm); err != nil {
+			return err
+		}
+	}
+
+	out, err := os.Create("/tmp/caplets.zip")
+	if err != nil {
+		return err
+	}
+	defer out.Close()
+
+	log.Info("downloading caplets from %s ...", caplets.InstallArchive)
+
+	resp, err := http.Get(caplets.InstallArchive)
+	if err != nil {
+		return err
+	}
+	defer resp.Body.Close()
+
+	if _, err := io.Copy(out, resp.Body); err != nil {
+		return err
+	}
+
+	log.Info("installing caplets to %s ...", caplets.InstallPath)
+
+	if _, err = core.Unzip("/tmp/caplets.zip", caplets.InstallBase); err != nil {
+		return err
+	}
+
+	os.RemoveAll(caplets.InstallPath)
+
+	return os.Rename(caplets.InstallPathArchive, caplets.InstallPath)
+}

session/events.go

@@ -63,6 +63,11 @@ func (p *EventPool) Listen() <-chan Event {
 	// will receive all the queued events
 	go func() {
 		for i := len(p.events) - 1; i >= 0; i-- {
+			defer func() {
+				if recover() != nil {
+
+				}
+			}()
 			l <- p.events[i]
 		}
 	}()