fix: working directory is temporarily switched when running a caplet in order to properly load/include files relative to the caplet itself

session/caplet.go

@@ -3,7 +3,6 @@ package session
 import (
 	"bufio"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"strings"
@@ -22,7 +21,6 @@ type Caplet struct {
 }
 
 var (
-	CapletsTree     = make(map[string][]string)
 	CapletLoadPaths = []string{
 		"./caplets/",
 		"/usr/share/bettercap/caplets/",
@@ -32,20 +30,6 @@ var (
 	cacheLock = sync.Mutex{}
 )
 
-func buildCapletsTree(path string, prefix string) {
-	files, _ := ioutil.ReadDir(path)
-	for _, file := range files {
-		filename := file.Name()
-		if strings.HasSuffix(filename, CapletSuffix) {
-			base := strings.TrimPrefix(path, prefix)
-			name := strings.Replace(filename, CapletSuffix, "", -1)
-			CapletsTree[base+name] = []string{}
-		} else if file.IsDir() {
-			buildCapletsTree(filepath.Join(path, filename)+"/", prefix)
-		}
-	}
-}
-
 func init() {
 	for _, path := range core.SepSplit(core.Trim(os.Getenv("CAPSPATH")), ":") {
 		if path = core.Trim(path); len(path) > 0 {
@@ -56,10 +40,6 @@ func init() {
 	for i, path := range CapletLoadPaths {
 		CapletLoadPaths[i], _ = filepath.Abs(path)
 	}
-
-	for _, path := range CapletLoadPaths {
-		buildCapletsTree(path, path)
-	}
 }
 
 func LoadCaplet(name string) (error, *Caplet) {
@@ -133,3 +113,41 @@ func parseCapletCommand(line string) (is bool, caplet *Caplet, argv []string) {
 
 	return false, nil, nil
 }
+
+func (cap *Caplet) Eval(s *Session, argv []string) error {
+	// the caplet might include other files (include directive, proxy modules, etc),
+	// temporarily change the working directory
+	cwd, err := os.Getwd()
+	if err != nil {
+		return fmt.Errorf("error while getting current working directory: %v", err)
+	}
+
+	capPath := filepath.Dir(cap.Path)
+	if err := os.Chdir(capPath); err != nil {
+		return fmt.Errorf("error while changing current working directory: %v", err)
+	}
+
+	defer func() {
+		if err := os.Chdir(cwd); err != nil {
+			s.Events.Log(core.ERROR, "error while restoring working directory: %v", err)
+		}
+	}()
+
+	if argv == nil {
+		argv = []string{}
+	}
+
+	for _, line := range cap.Code {
+		// replace $0 with argv[0], $1 with argv[1] and so on
+		for i, arg := range argv {
+			what := fmt.Sprintf("$%d", i)
+			line = strings.Replace(line, what, arg, -1)
+		}
+
+		if err = s.Run(line + "\n"); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}

session/session.go

@@ -5,13 +5,10 @@ import (
 	"fmt"
 	"net"
 	"os"
-	"os/signal"
 	"regexp"
 	"runtime"
 	"runtime/pprof"
 	"sort"
-	"strings"
-	"syscall"
 	"time"
 
 	"github.com/bettercap/readline"
@@ -65,70 +62,6 @@ type Session struct {
 	UnkCmdCallback UnknownCommandCallback `json:"-"`
 }
 
-func ParseCommands(line string) []string {
-	args := []string{}
-	buf := ""
-
-	singleQuoted := false
-	doubleQuoted := false
-	finish := false
-
-	for _, c := range line {
-		switch c {
-		case ';':
-			if !singleQuoted && !doubleQuoted {
-				finish = true
-			} else {
-				buf += string(c)
-			}
-
-		case '"':
-			if doubleQuoted {
-				// finish of quote
-				doubleQuoted = false
-			} else if singleQuoted {
-				// quote initiated with ', so we ignore it
-				buf += string(c)
-			} else {
-				// quote init here
-				doubleQuoted = true
-			}
-
-		case '\'':
-			if singleQuoted {
-				singleQuoted = false
-			} else if doubleQuoted {
-				buf += string(c)
-			} else {
-				singleQuoted = true
-			}
-
-		default:
-			buf += string(c)
-		}
-
-		if finish {
-			args = append(args, buf)
-			finish = false
-			buf = ""
-		}
-	}
-
-	if len(buf) > 0 {
-		args = append(args, buf)
-	}
-
-	cmds := make([]string, 0)
-	for _, cmd := range args {
-		cmd = core.Trim(cmd)
-		if cmd != "" || (len(cmd) > 0 && cmd[0] != '#') {
-			cmds = append(cmds, cmd)
-		}
-	}
-
-	return cmds
-}
-
 func New() (*Session, error) {
 	var err error
 
@@ -182,70 +115,6 @@ func (s *Session) Module(name string) (err error, mod Module) {
 	return fmt.Errorf("Module %s not found", name), mod
 }
 
-func (s *Session) setupReadline() error {
-	var err error
-
-	pcompleters := make([]readline.PrefixCompleterInterface, 0)
-	for _, h := range s.CoreHandlers {
-		if h.Completer == nil {
-			pcompleters = append(pcompleters, readline.PcItem(h.Name))
-		} else {
-			pcompleters = append(pcompleters, h.Completer)
-		}
-	}
-
-	tree := make(map[string][]string)
-	for _, m := range s.Modules {
-		for _, h := range m.Handlers() {
-			parts := strings.Split(h.Name, " ")
-			name := parts[0]
-
-			if _, found := tree[name]; !found {
-				tree[name] = []string{}
-			}
-
-			var appendedOption = strings.Join(parts[1:], " ")
-
-			if len(appendedOption) > 0 && !containsCapitals(appendedOption) {
-				tree[name] = append(tree[name], appendedOption)
-			}
-		}
-	}
-
-	for root, subElems := range CapletsTree {
-		item := readline.PcItem(root)
-		item.Children = []readline.PrefixCompleterInterface{}
-		for _, child := range subElems {
-			item.Children = append(item.Children, readline.PcItem(child))
-		}
-		pcompleters = append(pcompleters, item)
-	}
-
-	history := ""
-	if !*s.Options.NoHistory {
-		history, _ = core.ExpandPath(HistoryFile)
-	}
-
-	cfg := readline.Config{
-		HistoryFile:     history,
-		InterruptPrompt: "^C",
-		EOFPrompt:       "exit",
-		AutoComplete:    readline.NewPrefixCompleter(pcompleters...),
-	}
-
-	s.Input, err = readline.NewEx(&cfg)
-	return err
-}
-
-func containsCapitals(s string) bool {
-	for _, ch := range s {
-		if ch < 133 && ch > 101 {
-			return false
-		}
-	}
-	return true
-}
-
 func (s *Session) Close() {
 	if *s.Options.Debug {
 		fmt.Printf("\nStopping modules and cleaning session state ...\n")
@@ -290,77 +159,6 @@ func (s *Session) Register(mod Module) error {
 	return nil
 }
 
-func (s *Session) startNetMon() {
-	// keep reading network events in order to add / update endpoints
-	go func() {
-		for event := range s.Queue.Activities {
-			if !s.Active {
-				return
-			}
-
-			if s.IsOn("net.recon") && event.Source {
-				addr := event.IP.String()
-				mac := event.MAC.String()
-
-				existing := s.Lan.AddIfNew(addr, mac)
-				if existing != nil {
-					existing.LastSeen = time.Now()
-				}
-			}
-		}
-	}()
-}
-
-func (s *Session) setupSignals() {
-	c := make(chan os.Signal)
-	signal.Notify(c, os.Interrupt, syscall.SIGTERM)
-	go func() {
-		<-c
-		fmt.Println()
-		s.Events.Log(core.WARNING, "Got SIGTERM")
-		s.Close()
-		os.Exit(0)
-	}()
-}
-
-func (s *Session) setupEnv() {
-	s.Env.Set("iface.index", fmt.Sprintf("%d", s.Interface.Index))
-	s.Env.Set("iface.name", s.Interface.Name())
-	s.Env.Set("iface.ipv4", s.Interface.IpAddress)
-	s.Env.Set("iface.ipv6", s.Interface.Ip6Address)
-	s.Env.Set("iface.mac", s.Interface.HwAddress)
-	s.Env.Set("gateway.address", s.Gateway.IpAddress)
-	s.Env.Set("gateway.mac", s.Gateway.HwAddress)
-
-	if found, v := s.Env.Get(PromptVariable); !found || v == "" {
-		s.Env.Set(PromptVariable, DefaultPrompt)
-	}
-
-	dbg := "false"
-	if *s.Options.Debug {
-		dbg = "true"
-	}
-	s.Env.WithCallback("log.debug", dbg, func(newValue string) {
-		newDbg := false
-		if newValue == "true" {
-			newDbg = true
-		}
-		s.Events.SetDebug(newDbg)
-	})
-
-	silent := "false"
-	if *s.Options.Silent {
-		silent = "true"
-	}
-	s.Env.WithCallback("log.silent", silent, func(newValue string) {
-		newSilent := false
-		if newValue == "true" {
-			newSilent = true
-		}
-		s.Events.SetSilent(newSilent)
-	})
-}
-
 func (s *Session) Start() error {
 	var err error
 
@@ -445,19 +243,6 @@ func (s *Session) IsOn(moduleName string) bool {
 	return false
 }
 
-func (s *Session) parseEnvTokens(str string) (string, error) {
-	// replace all {env.something} with their values
-	for _, m := range reEnvVarCapture.FindAllString(str, -1) {
-		varName := strings.Trim(strings.Replace(m, "env.", "", -1), "{}")
-		if found, value := s.Env.Get(varName); found {
-			str = strings.Replace(str, m, value, -1)
-		} else {
-			return "", fmt.Errorf("variable '%s' is not defined", varName)
-		}
-	}
-	return str, nil
-}
-
 func (s *Session) Refresh() {
 	p, _ := s.parseEnvTokens(s.Prompt.Render(s))
 	s.Input.SetPrompt(p)
@@ -475,13 +260,7 @@ func (s *Session) RunCaplet(filename string) error {
 		return err
 	}
 
-	for _, line := range caplet.Code {
-		if err = s.Run(line + "\n"); err != nil {
-			return err
-		}
-	}
-
-	return nil
+	return caplet.Eval(s, nil)
 }
 
 func (s *Session) Run(line string) error {
@@ -491,6 +270,7 @@ func (s *Session) Run(line string) error {
 	// to 'arp.spoof on' (fixes #178)
 	line = reCmdSpaceCleaner.ReplaceAllString(line, "$1 $2")
 
+	// replace all {env.something} with their values
 	line, err := s.parseEnvTokens(line)
 	if err != nil {
 		return err
@@ -514,18 +294,7 @@ func (s *Session) Run(line string) error {
 
 	// is it a caplet command?
 	if parsed, caplet, argv := parseCapletCommand(line); parsed {
-		for _, line := range caplet.Code {
-			// replace $0 with argv[0], $1 with argv[1] and so on
-			for i, arg := range argv {
-				line = strings.Replace(line, fmt.Sprintf("$%d", i), arg, -1)
-			}
-
-			if err = s.Run(line + "\n"); err != nil {
-				return err
-			}
-		}
-
-		return nil
+		return caplet.Eval(s, argv)
 	}
 
 	// is it a proxy module custom command?

session/session_parse.go

@@ -0,0 +1,84 @@
+package session
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/bettercap/bettercap/core"
+)
+
+func ParseCommands(line string) []string {
+	args := []string{}
+	buf := ""
+
+	singleQuoted := false
+	doubleQuoted := false
+	finish := false
+
+	for _, c := range line {
+		switch c {
+		case ';':
+			if !singleQuoted && !doubleQuoted {
+				finish = true
+			} else {
+				buf += string(c)
+			}
+
+		case '"':
+			if doubleQuoted {
+				// finish of quote
+				doubleQuoted = false
+			} else if singleQuoted {
+				// quote initiated with ', so we ignore it
+				buf += string(c)
+			} else {
+				// quote init here
+				doubleQuoted = true
+			}
+
+		case '\'':
+			if singleQuoted {
+				singleQuoted = false
+			} else if doubleQuoted {
+				buf += string(c)
+			} else {
+				singleQuoted = true
+			}
+
+		default:
+			buf += string(c)
+		}
+
+		if finish {
+			args = append(args, buf)
+			finish = false
+			buf = ""
+		}
+	}
+
+	if len(buf) > 0 {
+		args = append(args, buf)
+	}
+
+	cmds := make([]string, 0)
+	for _, cmd := range args {
+		cmd = core.Trim(cmd)
+		if cmd != "" || (len(cmd) > 0 && cmd[0] != '#') {
+			cmds = append(cmds, cmd)
+		}
+	}
+
+	return cmds
+}
+
+func (s *Session) parseEnvTokens(str string) (string, error) {
+	for _, m := range reEnvVarCapture.FindAllString(str, -1) {
+		varName := strings.Trim(strings.Replace(m, "env.", "", -1), "{}")
+		if found, value := s.Env.Get(varName); found {
+			str = strings.Replace(str, m, value, -1)
+		} else {
+			return "", fmt.Errorf("variable '%s' is not defined", varName)
+		}
+	}
+	return str, nil
+}

session/session_setup.go

@@ -0,0 +1,140 @@
+package session
+
+import (
+	"fmt"
+	"os"
+	"os/signal"
+	"strings"
+	"syscall"
+	"time"
+
+	"github.com/bettercap/readline"
+
+	"github.com/bettercap/bettercap/core"
+)
+
+func containsCapitals(s string) bool {
+	for _, ch := range s {
+		if ch < 133 && ch > 101 {
+			return false
+		}
+	}
+	return true
+}
+
+func (s *Session) setupReadline() error {
+	var err error
+
+	pcompleters := make([]readline.PrefixCompleterInterface, 0)
+	for _, h := range s.CoreHandlers {
+		if h.Completer == nil {
+			pcompleters = append(pcompleters, readline.PcItem(h.Name))
+		} else {
+			pcompleters = append(pcompleters, h.Completer)
+		}
+	}
+
+	tree := make(map[string][]string)
+	for _, m := range s.Modules {
+		for _, h := range m.Handlers() {
+			parts := strings.Split(h.Name, " ")
+			name := parts[0]
+
+			if _, found := tree[name]; !found {
+				tree[name] = []string{}
+			}
+
+			var appendedOption = strings.Join(parts[1:], " ")
+
+			if len(appendedOption) > 0 && !containsCapitals(appendedOption) {
+				tree[name] = append(tree[name], appendedOption)
+			}
+		}
+	}
+
+	history := ""
+	if !*s.Options.NoHistory {
+		history, _ = core.ExpandPath(HistoryFile)
+	}
+
+	cfg := readline.Config{
+		HistoryFile:     history,
+		InterruptPrompt: "^C",
+		EOFPrompt:       "exit",
+		AutoComplete:    readline.NewPrefixCompleter(pcompleters...),
+	}
+
+	s.Input, err = readline.NewEx(&cfg)
+	return err
+}
+
+func (s *Session) startNetMon() {
+	// keep reading network events in order to add / update endpoints
+	go func() {
+		for event := range s.Queue.Activities {
+			if !s.Active {
+				return
+			}
+
+			if s.IsOn("net.recon") && event.Source {
+				addr := event.IP.String()
+				mac := event.MAC.String()
+
+				existing := s.Lan.AddIfNew(addr, mac)
+				if existing != nil {
+					existing.LastSeen = time.Now()
+				}
+			}
+		}
+	}()
+}
+
+func (s *Session) setupSignals() {
+	c := make(chan os.Signal)
+	signal.Notify(c, os.Interrupt, syscall.SIGTERM)
+	go func() {
+		<-c
+		fmt.Println()
+		s.Events.Log(core.WARNING, "Got SIGTERM")
+		s.Close()
+		os.Exit(0)
+	}()
+}
+
+func (s *Session) setupEnv() {
+	s.Env.Set("iface.index", fmt.Sprintf("%d", s.Interface.Index))
+	s.Env.Set("iface.name", s.Interface.Name())
+	s.Env.Set("iface.ipv4", s.Interface.IpAddress)
+	s.Env.Set("iface.ipv6", s.Interface.Ip6Address)
+	s.Env.Set("iface.mac", s.Interface.HwAddress)
+	s.Env.Set("gateway.address", s.Gateway.IpAddress)
+	s.Env.Set("gateway.mac", s.Gateway.HwAddress)
+
+	if found, v := s.Env.Get(PromptVariable); !found || v == "" {
+		s.Env.Set(PromptVariable, DefaultPrompt)
+	}
+
+	dbg := "false"
+	if *s.Options.Debug {
+		dbg = "true"
+	}
+	s.Env.WithCallback("log.debug", dbg, func(newValue string) {
+		newDbg := false
+		if newValue == "true" {
+			newDbg = true
+		}
+		s.Events.SetDebug(newDbg)
+	})
+
+	silent := "false"
+	if *s.Options.Silent {
+		silent = "true"
+	}
+	s.Env.WithCallback("log.silent", silent, func(newValue string) {
+		newSilent := false
+		if newValue == "true" {
+			newSilent = true
+		}
+		s.Events.SetSilent(newSilent)
+	})
+}