Passmgr (#3)

* password manager plugin

cli/cli.go

@@ -13,6 +13,7 @@ import (
 	"github.com/chzyer/readline"
 	"github.com/viert/xc/config"
 	"github.com/viert/xc/log"
+	"github.com/viert/xc/passmgr"
 	"github.com/viert/xc/remote"
 	"github.com/viert/xc/store"
 	"github.com/viert/xc/term"
@@ -44,6 +45,7 @@ type Cli struct {
 	prependHostnames bool
 	progressBar      bool
 	debug            bool
+	usePasswordMgr   bool
 
 	interpreter     string
 	sudoInterpreter string
@@ -114,6 +116,16 @@ func New(cfg *config.XCConfig, backend store.Backend) (*Cli, error) {
 	cli.outputFileName = ""
 	cli.outputFile = nil
 
+	if cfg.PasswordManagerPath != "" {
+		term.Warnf("Loading password manager from %s\n", cfg.PasswordManagerPath)
+		err = passmgr.Load(cfg.PasswordManagerPath)
+		if err != nil {
+			term.Errorf("Error initializing password manager: %s\n", err)
+		} else {
+			cli.usePasswordMgr = true
+		}
+	}
+
 	remote.Initialize(cli.sshThreads, cli.user)
 	remote.SetPrependHostnames(cli.prependHostnames)
 	remote.SetRemoteTmpdir(cfg.RemoteTmpdir)
@@ -276,9 +288,10 @@ func (c *Cli) confirm(msg string) bool {
 }
 
 func (c *Cli) acquirePasswd() {
-	if c.raiseType == remote.RTNone {
+	if c.raiseType == remote.RTNone || c.usePasswordMgr {
 		return
 	}
+
 	if c.raisePasswd == "" {
 		c.doPasswd("passwd", "")
 	}
@@ -407,3 +420,23 @@ func (c *Cli) dorunscript(mode execMode, argsLine string) {
 	r.ErrorHosts = append(r.ErrorHosts, copyError...)
 	r.Print()
 }
+
+func doOnOff(propName string, propRef *bool, args []string) {
+	if len(args) < 1 {
+		value := "off"
+		if *propRef {
+			value = "on"
+		}
+		term.Warnf("%s is %s\n", propName, value)
+		return
+	}
+	switch args[0] {
+	case "on":
+		*propRef = true
+	case "off":
+		*propRef = false
+	default:
+		term.Errorf("Invalid %s vaue. Please use either \"on\" or \"off\"\n", propName)
+		return
+	}
+}

cli/completer.go

@@ -40,7 +40,7 @@ func newCompleter(store *store.Store, commands []string) *completer {
 	x.handlers["c_runscript"] = x.completeDistribute
 	x.handlers["p_runscript"] = x.completeDistribute
 
-	helpTopics := append(commands, "expressions", "config", "rcfiles")
+	helpTopics := append(commands, "expressions", "config", "rcfiles", "passmgr")
 	x.handlers["help"] = staticCompleter(helpTopics)
 	return x
 }

cli/handlers.go

@@ -8,6 +8,8 @@ import (
 	"strconv"
 	"syscall"
 
+	"github.com/viert/xc/passmgr"
+
 	"github.com/viert/xc/remote"
 	"github.com/viert/xc/term"
 )
@@ -46,6 +48,7 @@ func (c *Cli) setupCmdHandlers() {
 	c.handlers["s_runscript"] = c.doSRunScript
 	c.handlers["c_runscript"] = c.doCRunScript
 	c.handlers["p_runscript"] = c.doPRunScript
+	c.handlers["use_password_manager"] = c.doUsePasswordManager
 
 	commands := make([]string, len(c.handlers))
 	i := 0
@@ -277,68 +280,29 @@ func (c *Cli) doDelay(name string, argsLine string, args ...string) {
 }
 
 func (c *Cli) doDebug(name string, argsLine string, args ...string) {
-	if len(args) < 1 {
-		value := "off"
-		if c.debug {
-			value = "on"
-		}
-		term.Warnf("Debug is %s\n", value)
-		return
-	}
-	switch args[0] {
-	case "on":
-		c.debug = true
-	case "off":
-		c.debug = false
-	default:
-		term.Errorf("Invalid debug value. Please use either \"on\" or \"off\"\n")
-		return
-	}
+	doOnOff("debug", &c.debug, args)
 	remote.SetDebug(c.debug)
 }
 
 func (c *Cli) doProgressBar(name string, argsLine string, args ...string) {
-	if len(args) < 1 {
-		value := "off"
-		if c.progressBar {
-			value = "on"
-		}
-		term.Warnf("Progressbar is %s\n", value)
-		return
-	}
-	switch args[0] {
-	case "on":
-		c.progressBar = true
-	case "off":
-		c.progressBar = false
-	default:
-		term.Errorf("Invalid progressbar value. Please use either \"on\" or \"off\"\n")
-		return
-	}
+	doOnOff("progressbar", &c.progressBar, args)
 	remote.SetProgressBar(c.progressBar)
 }
 
 func (c *Cli) doPrependHostnames(name string, argsLine string, args ...string) {
-	if len(args) < 1 {
-		value := "off"
-		if c.prependHostnames {
-			value = "on"
-		}
-		term.Warnf("prepend_hostnames is %s\n", value)
-		return
-	}
-	switch args[0] {
-	case "on":
-		c.prependHostnames = true
-	case "off":
-		c.prependHostnames = false
-	default:
-		term.Errorf("Invalid prepend_hostnames value. Please use either \"on\" or \"off\"\n")
-		return
-	}
+	doOnOff("prepend_hostnames", &c.prependHostnames, args)
 	remote.SetPrependHostnames(c.prependHostnames)
 }
 
+func (c *Cli) doUsePasswordManager(name string, argsLine string, args ...string) {
+	doOnOff("use_password_manager", &c.usePasswordMgr, args)
+	if c.usePasswordMgr && !passmgr.Ready() {
+		term.Errorf("Password manager is not ready\n")
+		c.usePasswordMgr = false
+	}
+	remote.SetUsePasswordManager(c.usePasswordMgr)
+}
+
 func (c *Cli) doReload(name string, argsLine string, args ...string) {
 	err := c.store.BackendReload()
 	if err != nil {
@@ -359,7 +323,7 @@ func (c *Cli) doInterpreter(name string, argsLine string, args ...string) {
 
 func (c *Cli) doConnectTimeout(name string, argsLine string, args ...string) {
 	if len(args) < 1 {
-		term.Warnf("connect_timeout = %s\n", c.connectTimeout)
+		term.Warnf("connect_timeout = %d\n", c.connectTimeout)
 		return
 	}
 	ct, err := strconv.ParseInt(args[0], 10, 64)

cli/help.go

@@ -161,6 +161,16 @@ It may be useful for configuring aliases (as they are dropped when xc exits) and
 Rcfile is just a number of xc commands in a text file.`,
 		},
 
+		"passmgr": &helpItem{
+			isTopic: true,
+			help: `Password manager is a golang plugin which must have two exported functions:
+func Init() error, which is called on xc start 
+func GetPass(host string) (password string), which is kinda self-explanatory
+
+For more info on how to write golang plugins, please refer to golang documentation or this article:
+https://medium.com/learning-the-go-programming-language/writing-modular-go-programs-with-plugins-ec46381ee1a9`,
+		},
+
 		"debug": &helpItem{
 			usage: "<on/off>",
 			help:  `An internal debug. May cause unexpected output. One shouldn't use it unless she knows what she's doing.`,
@@ -318,6 +328,12 @@ xc moves on to the next server.`,
 without arguments, prints the current value.`,
 		},
 
+		"use_password_manager": &helpItem{
+			usage: "[<on/off>]",
+			help: `Sets the password manager on/off. If no value is given, prints the current value.
+If password manager is not ready, setting this value to "on" will print an error.`,
+		},
+
 		"user": &helpItem{
 			usage: "<username>",
 			help:  `Sets the username for all the execution commands. This is used to get access to hosts via ssh/scp.`,
@@ -370,7 +386,8 @@ List of commands:
     reload                                 reloads hosts and groups data from inventoree
     runscript                              runs a local script on a number of remote hosts
     serial                                 shortcut for "mode serial"
-    ssh                                    starts ssh session to a number of hosts sequentally
-    user                                   sets current user
-`)
+	ssh                                    starts ssh session to a number of hosts sequentally
+	use_password_manager                   turns password manager on/off
+	user                                   sets current user`)
+	fmt.Println()
 }

config/config.go

@@ -39,6 +39,9 @@ interpreter_su = su -
 type = conductor
 url = http://c.inventoree.ru
 work_groups = 
+
+[passmgr]
+path =
 `
 
 // BackendType is a backend type enum
@@ -61,28 +64,29 @@ type BackendConfig struct {
 
 // XCConfig represents a configuration struct for XC
 type XCConfig struct {
-	Readline          *readline.Config
-	BackendCfg        *BackendConfig
-	User              string
-	SSHThreads        int
-	SSHConnectTimeout int
-	PingCount         int
-	RemoteTmpdir      string
-	Mode              string
-	RaiseType         string
-	Delay             int
-	RCfile            string
-	CacheDir          string
-	CacheTTL          time.Duration
-	Debug             bool
-	ProgressBar       bool
-	PrependHostnames  bool
-	LogFile           string
-	ExitConfirm       bool
-	ExecConfirm       bool
-	SudoInterpreter   string
-	SuInterpreter     string
-	Interpreter       string
+	Readline            *readline.Config
+	BackendCfg          *BackendConfig
+	User                string
+	SSHThreads          int
+	SSHConnectTimeout   int
+	PingCount           int
+	RemoteTmpdir        string
+	Mode                string
+	RaiseType           string
+	Delay               int
+	RCfile              string
+	CacheDir            string
+	CacheTTL            time.Duration
+	Debug               bool
+	ProgressBar         bool
+	PrependHostnames    bool
+	LogFile             string
+	ExitConfirm         bool
+	ExecConfirm         bool
+	SudoInterpreter     string
+	SuInterpreter       string
+	Interpreter         string
+	PasswordManagerPath string
 }
 
 const (
@@ -310,5 +314,7 @@ func read(filename string, secondPass bool) (*XCConfig, error) {
 		return nil, fmt.Errorf("Error configuring backend: backend type is not defined")
 	}
 
-	return cfg, err
+	cfg.PasswordManagerPath, _ = props.GetString("passmgr.path")
+
+	return cfg, nil
 }

passmgr/passmgr.go

@@ -0,0 +1,62 @@
+package passmgr
+
+import (
+	"fmt"
+	"plugin"
+)
+
+type initFunc func() error
+type acquireFunc func(string) string
+
+const (
+	initFuncName    = "Init"
+	acquireFuncName = "GetPass"
+)
+
+var (
+	p             *plugin.Plugin
+	initialized   bool
+	pluginInit    initFunc
+	pluginAcquire acquireFunc
+)
+
+// Load loads a password manager library
+func Load(filename string) error {
+	var err error
+	p, err = plugin.Open(filename)
+	if err != nil {
+		return err
+	}
+
+	init, err := p.Lookup(initFuncName)
+	if err != nil {
+		return err
+	}
+	pluginInit, initialized = init.(initFunc)
+	if !initialized {
+		return fmt.Errorf("invalid plugin `%s() error` function signature", initFuncName)
+	}
+
+	acq, err := p.Lookup(acquireFuncName)
+	if err != nil {
+		return err
+	}
+	pluginAcquire, initialized = acq.(acquireFunc)
+	if !initialized {
+		return fmt.Errorf("invalid plugin `%s(string) string` function signature", acquireFuncName)
+	}
+	return nil
+}
+
+// GetPass returns password for a given host from password manager
+func GetPass(hostname string) string {
+	if !initialized {
+		return ""
+	}
+	return pluginAcquire(hostname)
+}
+
+// Ready returns a bool value indicating if the passmgr is initialized and ready to use
+func Ready() bool {
+	return initialized
+}

remote/remote.go

@@ -10,15 +10,16 @@ import (
 )
 
 var (
-	pool                    *Pool
-	currentUser             string
-	currentPassword         string
-	currentRaise            RaiseType
-	currentProgressBar      bool
-	currentPrependHostnames bool
-	currentRemoteTmpdir     string
-	currentDebug            bool
-	outputFile              *os.File
+	pool                      *Pool
+	currentUser               string
+	currentPassword           string
+	currentRaise              RaiseType
+	currentUsePasswordManager bool
+	currentProgressBar        bool
+	currentPrependHostnames   bool
+	currentRemoteTmpdir       string
+	currentDebug              bool
+	outputFile                *os.File
 
 	noneInterpreter string
 	suInterpreter   string
@@ -83,6 +84,11 @@ func SetPrependHostnames(prependHostnames bool) {
 	currentPrependHostnames = prependHostnames
 }
 
+// SetUsePasswordManager sets using passmgr on/off
+func SetUsePasswordManager(usePasswordMgr bool) {
+	currentUsePasswordManager = usePasswordMgr
+}
+
 // SetConnectTimeout sets the ssh connect timeout in sshOptions
 func SetConnectTimeout(timeout int) {
 	sshOptions["ConnectTimeout"] = fmt.Sprintf("%d", timeout)

remote/runcmd.go

@@ -10,14 +10,17 @@ import (
 	"github.com/kr/pty"
 	"github.com/npat-efault/poller"
 	"github.com/viert/xc/log"
+	"github.com/viert/xc/passmgr"
 )
 
 func (w *Worker) runcmd(task *Task) int {
-	var err error
-	var n int
-	var passwordSent bool
+	var (
+		err          error
+		n            int
+		password     string
+		passwordSent bool
+	)
 
-	passwordSent = currentRaise == RTNone
 	cmd := createSSHCmd(task.Hostname, task.Cmd)
 	cmd.Env = append(os.Environ(), environment...)
 
@@ -38,6 +41,17 @@ func (w *Worker) runcmd(task *Task) int {
 	shouldSkipEcho := false
 	msgCount := 0
 
+	if currentRaise != RTNone {
+		passwordSent = false
+		if currentUsePasswordManager {
+			password = passmgr.GetPass(task.Hostname)
+		} else {
+			password = currentPassword
+		}
+	} else {
+		passwordSent = true
+	}
+
 execLoop:
 	for {
 		if w.forceStopped() {
@@ -68,7 +82,7 @@ execLoop:
 			// Trying to find Password prompt in first 5 chunks of data from server
 			if msgCount < 5 {
 				if !passwordSent && exPasswdPrompt.Match(chunk) {
-					ptmx.Write([]byte(currentPassword + "\n"))
+					ptmx.Write([]byte(password + "\n"))
 					passwordSent = true
 					shouldSkipEcho = true
 					continue