Merge branch 'metalint'

Signed-off-by: Russ Magee <rmagee@gmail.com>

Makefile

@@ -1,4 +1,4 @@
-.PHONY: vis clean common client server passwd subpkgs install uninstall
+.PHONY: lint vis clean common client server passwd subpkgs install uninstall reinstall
 
 SUBPKGS = logger spinsult hkexnet herradurakex
 TOOLS = hkexpasswd hkexsh hkexshd
@@ -59,6 +59,13 @@ vis:
 	  make -C hkexpasswd vis; \
 	fi
 
+lint:
+	make -C hkexpasswd lint
+	make -C hkexshd lint
+	make -C hkexsh lint
+
+reinstall: uninstall install
+
 install:
 	cp hkexsh/hkexsh $(INSTPREFIX)/bin
 ifeq ($(MSYSTEM),)

consts.go

@@ -1,4 +1,4 @@
-// Common constants for the HKExSh
+// Package hkexsh - common constants for the HKExSh
 //
 // Copyright (c) 2017-2018 Russell Magee
 // Licensed under the terms of the MIT license (see LICENSE.mit in this
@@ -7,5 +7,6 @@
 // golang implementation by Russ Magee (rmagee_at_gmail.com)
 package hkexsh
 
+// Version string returned by tools
 const Version = "0.7pre (NO WARRANTY)"
 

hkexauth.go

@@ -24,15 +24,15 @@ import (
 
 func userExistsOnSystem(who string) bool {
 	_, userErr := user.Lookup(who)
-	if userErr != nil {
+	return userErr == nil
-		return false
-	} else {
-		return true
-	}
 }
 
+// AuthUserByPasswd checks user login information using a password.
+// This checks /etc/hkexsh.passwd for auth info, and system /etc/passwd
+// to cross-check the user actually exists.
+// nolint: gocyclo
 func AuthUserByPasswd(username string, auth string, fname string) (valid bool, allowedCmds string) {
-	b, e := ioutil.ReadFile(fname)
+	b, e := ioutil.ReadFile(fname) // nolint: gosec
 	if e != nil {
 		valid = false
 		log.Println("ERROR: Cannot read hkexsh.passwd file!")
@@ -60,7 +60,10 @@ func AuthUserByPasswd(username string, auth string, fname string) (valid bool, a
 		}
 
 		if username == record[0] {
-			tmp, _ := bcrypt.Hash(auth, record[1])
+			tmp, err := bcrypt.Hash(auth, record[1])
+			if err != nil {
+				break
+			}
 			if tmp == record[2] && username != "$nosuchuser$" {
 				valid = true
 			}
@@ -71,7 +74,6 @@ func AuthUserByPasswd(username string, auth string, fname string) (valid bool, a
 	for i := range b {
 		b[i] = 0
 	}
-	b = nil
 	r = nil
 	runtime.GC()
 
@@ -81,6 +83,11 @@ func AuthUserByPasswd(username string, auth string, fname string) (valid bool, a
 	return
 }
 
+// AuthUserByToken checks user login information against an auth token.
+// Auth tokens are stored in each user's $HOME/.hkexsh_id and are requested
+// via the -g option.
+// The function also check system /etc/passwd to cross-check the user
+// actually exists.
 func AuthUserByToken(username string, connhostname string, auth string) (valid bool) {
 	auth = strings.TrimSpace(auth)
 	u, ue := user.Lookup(username)
@@ -111,7 +118,8 @@ func AuthUserByToken(username string, connhostname string, auth string) (valid b
 
 		if (connhostname == record[0]) &&
 			(auth == strings.Join([]string{record[0], record[1]}, ":")) {
-			return true
+			valid = true
+			break
 		}
 	}
 	if !userExistsOnSystem(username) {

hkexpasswd/Makefile

@@ -1,4 +1,4 @@
-.PHONY: clean all vis
+.PHONY: clean all vis lint
 
 EXTPKGS = bytes,errors,flag,fmt,internal,io,log,net,os,path,runtime,time,strings,sync,syscall,binary,encoding
 EXE = $(notdir $(shell pwd))
@@ -12,3 +12,5 @@ clean:
 vis:
 	go-callvis -skipbrowser -png -svg -output hkexpasswd-vis -ignore $(EXTPKGS) -group pkg,type .
 
+lint:
+	-gometalinter --deadline=60s | sort

hkexpasswd/hkexpasswd.go

@@ -21,6 +21,7 @@ import (
 	"github.com/jameskeane/bcrypt"
 )
 
+// nolint: gocyclo
 func main() {
 	var pfName string
 	var newpw string
@@ -84,7 +85,7 @@ func main() {
 	}
 	//fmt.Println("Salt:", salt, "Hash:", hash)
 
-	b, err := ioutil.ReadFile(pfName)
+	b, err := ioutil.ReadFile(pfName) // nolint: gosec
 	if err != nil {
 		log.Fatal(err)
 	}
@@ -100,7 +101,7 @@ func main() {
 	}
 
 	recFound := false
-	for i, _ := range records {
+	for i := range records {
 		//fmt.Println(records[i])
 		if records[i][0] == uname {
 			recFound = true
@@ -124,8 +125,14 @@ func main() {
 	w := csv.NewWriter(outFile)
 	w.Comma = ':'
 	//w.FieldsPerRecord = 4 // username:salt:authCookie:disallowedCmdList (a,b,...)
-	w.Write([]string{"#username", "salt", "authCookie"/*, "disallowedCmdList"*/})
+	err = w.Write([]string{"#username", "salt", "authCookie" /*, "disallowedCmdList"*/})
-	w.WriteAll(records)
+	if err != nil {
+		log.Fatal(err)
+	}
+	err = w.WriteAll(records)
+	if err != nil {
+		log.Fatal(err)
+	}
 	if err = w.Error(); err != nil {
 		log.Fatal(err)
 	}

hkexsession.go

@@ -13,6 +13,7 @@ import (
 	"runtime"
 )
 
+// Session holds essential bookkeeping info about an active session.
 type Session struct {
 	op         []byte
 	who        []byte
@@ -29,58 +30,80 @@ func (h *Session) String() string {
 		h.op, h.who, h.cmd, h.AuthCookie(false), h.status)
 }
 
+// Op returns the op code of the Session (interactive shell, cmd, ...)
 func (h Session) Op() []byte {
 	return h.op
 }
 
+// SetOp stores the op code desired for a Session.
 func (h *Session) SetOp(o []byte) {
 	h.op = o
 }
 
+// Who returns the user associated with a Session.
 func (h Session) Who() []byte {
 	return h.who
 }
 
+// SetWho sets the username associated with a Session.
 func (h *Session) SetWho(w []byte) {
 	h.who = w
 }
 
+// ConnHost returns the connecting hostname/IP string for a Session.
 func (h Session) ConnHost() []byte {
 	return h.connhost
 }
 
+// SetConnHost stores the connecting hostname/IP string for a Session.
 func (h *Session) SetConnHost(n []byte) {
 	h.connhost = n
 }
 
+// TermType returns the TERM env variable reported by the client initiating
+// a Session.
 func (h Session) TermType() []byte {
 	return h.termtype
 }
 
+// SetTermType stores the TERM env variable supplied by the client initiating
+// a Session.
 func (h *Session) SetTermType(t []byte) {
 	h.termtype = t
 }
 
+// Cmd returns the command requested for execution by a client initiating
+// the Session.
 func (h Session) Cmd() []byte {
 	return h.cmd
 }
 
+// SetCmd stores the command request by the client for execution when initiating
+// the Session.
 func (h *Session) SetCmd(c []byte) {
 	h.cmd = c
 }
 
+// AuthCookie returns the authcookie (essentially the password) used for
+// authorization of the Session. This return value is censored unless
+// reallyShow is true (so dumps of Session Info do not accidentally leak it).
 func (h Session) AuthCookie(reallyShow bool) []byte {
 	if reallyShow {
 		return h.authCookie
-	} else {
-		return []byte("**REDACTED**")
 	}
+	return []byte("**REDACTED**")
 }
 
+// SetAuthCookie stores the authcookie (essential the password) used to
+// authenticate the Session.
 func (h *Session) SetAuthCookie(a []byte) {
 	h.authCookie = a
 }
 
+// ClearAuthCookie attempts to scrub the Session's stored authcookie.
+//
+// This should of course be called as soon as possible after authentication
+// and it is no longer required.
 func (h *Session) ClearAuthCookie() {
 	for i := range h.authCookie {
 		h.authCookie[i] = 0
@@ -88,14 +111,20 @@ func (h *Session) ClearAuthCookie() {
 	runtime.GC()
 }
 
+// Status returns the (current) Session status code.
+//
+// This usually corresponds to a UNIX shell exit code, but
+// extended codes are returns at times to indicate internal errors.
 func (h Session) Status() uint32 {
 	return h.status
 }
 
+// SetStatus stores the current Session status code.
 func (h *Session) SetStatus(s uint32) {
 	h.status = s
 }
 
+// NewSession returns a new Session record.
 func NewSession(op, who, connhost, ttype, cmd, authcookie []byte, status uint32) *Session {
 	return &Session{
 		op:         op,

hkexsh/Makefile

@@ -1,4 +1,4 @@
-.PHONY: clean all vis
+.PHONY: clean all vis lint
 
 EXTPKGS = bytes,errors,flag,fmt,internal,io,log,net,os,path,runtime,time,strings,sync,syscall,binary,encoding
 EXE = $(notdir $(shell pwd))
@@ -12,3 +12,6 @@ clean:
 vis:
 	go-callvis -skipbrowser -output hkexsh-vis -ignore $(EXTPKGS) -group pkg,type .
 	../fixup-gv.sh hkexsh.go && cat hkexsh-vis.gv | dot -Tpng -ohkexsh-vis.gv.png
+
+lint:
+	-gometalinter --deadline=60s | sort

hkexsh/hkexsh.go

@@ -66,6 +66,7 @@ func GetSize() (cols, rows int, err error) {
 }
 
 // doCopyMode begins a secure hkexsh local<->remote file copy operation.
+// TODO: reduce gocyclo
 func doCopyMode(conn *hkexnet.Conn, remoteDest bool, files string, rec *hkexsh.Session) (exitStatus uint32, err error) {
 	if remoteDest {
 		log.Println("local files:", files, "remote filepath:", string(rec.Cmd()))
@@ -305,15 +306,15 @@ func doShellMode(isInteractive bool, conn *hkexnet.Conn, oldState *hkexsh.State,
 }
 
 func usageShell() {
-	fmt.Fprintf(os.Stderr, "Usage of %s:\n", os.Args[0])
+	fmt.Fprintf(os.Stderr, "Usage of %s:\n", os.Args[0])            // nolint: errcheck
-	fmt.Fprintf(os.Stderr, "%s [opts] [user]@server\n", os.Args[0])
+	fmt.Fprintf(os.Stderr, "%s [opts] [user]@server\n", os.Args[0]) // nolint: errcheck
 	flag.PrintDefaults()
 }
 
 func usageCp() {
-	fmt.Fprintf(os.Stderr, "Usage of %s:\n", os.Args[0])
+	fmt.Fprintf(os.Stderr, "Usage of %s:\n", os.Args[0])                                         // nolint: errcheck
-	fmt.Fprintf(os.Stderr, "%s [opts] srcFileOrDir [...] [user]@server[:dstpath]\n", os.Args[0])
+	fmt.Fprintf(os.Stderr, "%s [opts] srcFileOrDir [...] [user]@server[:dstpath]\n", os.Args[0]) // nolint: errcheck
-	fmt.Fprintf(os.Stderr, "%s [opts] [user]@server[:srcFileOrDir] dstPath\n", os.Args[0])
+	fmt.Fprintf(os.Stderr, "%s [opts] [user]@server[:srcFileOrDir] dstPath\n", os.Args[0])       // nolint: errcheck
 	flag.PrintDefaults()
 }
 
@@ -329,17 +330,15 @@ func reqTunnel(hc *hkexnet.Conn, lp uint16, p string /*net.Addr*/, rp uint16) {
 	// Write request to server so it can attempt to set up its end
 	var bTmp bytes.Buffer
 	if e := binary.Write(&bTmp, binary.BigEndian, lp); e != nil {
-		fmt.Fprintln(os.Stderr, "reqTunnel:", e)
+		fmt.Fprintln(os.Stderr, "reqTunnel:", e) // nolint: errcheck
 	}
 	if e := binary.Write(&bTmp, binary.BigEndian, rp); e != nil {
-		fmt.Fprintln(os.Stderr, "reqTunnel:", e)
+		fmt.Fprintln(os.Stderr, "reqTunnel:", e) // nolint: errcheck
 	}
-	_ = logger.LogDebug(fmt.Sprintln("[Client sending CSOTunSetup]"))
+	_ = logger.LogDebug(fmt.Sprintln("[Client sending CSOTunSetup]")) // nolint: gosec
 	if n, e := hc.WritePacket(bTmp.Bytes(), hkexnet.CSOTunSetup); e != nil || n != len(bTmp.Bytes()) {
-		fmt.Fprintln(os.Stderr, "reqTunnel:", e)
+		fmt.Fprintln(os.Stderr, "reqTunnel:", e) // nolint: errcheck
 	}
-
-	return
 }
 
 func parseNonSwitchArgs(a []string) (user, host, path string, isDest bool, otherArgs []string) {
@@ -384,7 +383,7 @@ func parseNonSwitchArgs(a []string) (user, host, path string, isDest bool, other
 }
 
 func launchTuns(conn *hkexnet.Conn, remoteHost string, tuns string) {
-	remAddrs, _ := net.LookupHost(remoteHost)
+	remAddrs, _ := net.LookupHost(remoteHost) // nolint: gosec
 
 	if tuns == "" {
 		return
@@ -393,7 +392,7 @@ func launchTuns(conn *hkexnet.Conn, remoteHost string, tuns string) {
 	tunSpecs := strings.Split(tuns, ",")
 	for _, tunItem := range tunSpecs {
 		var lPort, rPort uint16
-		_, _ = fmt.Sscanf(tunItem, "%d:%d", &lPort, &rPort)
+		_, _ = fmt.Sscanf(tunItem, "%d:%d", &lPort, &rPort) // nolint: gosec
 		reqTunnel(conn, lPort, remAddrs[0], rPort)
 	}
 }
@@ -401,13 +400,31 @@ func launchTuns(conn *hkexnet.Conn, remoteHost string, tuns string) {
 func sendSessionParams(conn io.Writer /* *hkexnet.Conn*/, rec *hkexsh.Session) (e error) {
 	_, e = fmt.Fprintf(conn, "%d %d %d %d %d %d\n",
 		len(rec.Op()), len(rec.Who()), len(rec.ConnHost()), len(rec.TermType()), len(rec.Cmd()), len(rec.AuthCookie(true)))
+	if e != nil {
+		return
+	}
 	_, e = conn.Write(rec.Op())
+	if e != nil {
+		return
+	}
 	_, e = conn.Write(rec.Who())
+	if e != nil {
+		return
+	}
 	_, e = conn.Write(rec.ConnHost())
+	if e != nil {
+		return
+	}
 	_, e = conn.Write(rec.TermType())
+	if e != nil {
+		return
+	}
 	_, e = conn.Write(rec.Cmd())
+	if e != nil {
+		return
+	}
 	_, e = conn.Write(rec.AuthCookie(true))
-	return
+	return e
 }
 
 // hkexsh - a client for secure shell and file copy operations.
@@ -421,6 +438,7 @@ func sendSessionParams(conn io.Writer /* *hkexnet.Conn*/, rec *hkexsh.Session) (
 // setting desired; as well as the intended operation mode for the
 // connection (app-specific, passed through to the server to use or
 // ignore at its discretion).
+// TODO: reduce gocyclo
 func main() {
 	version := hkexsh.Version
 	var vopt bool
@@ -481,7 +499,7 @@ func main() {
 	// Set defaults if user doesn't specify user, path or port
 	var uname string
 	if remoteUser == "" {
-		u, _ := user.Current()
+		u, _ := user.Current() // nolint: gosec
 		uname = u.Username
 	} else {
 		uname = remoteUser
@@ -547,7 +565,7 @@ func main() {
 	// either the shell session or copy operation.
 	_ = shellMode
 
-	Log, _ = logger.New(logger.LOG_USER|logger.LOG_DEBUG|logger.LOG_NOTICE|logger.LOG_ERR, "hkexsh")
+	Log, _ = logger.New(logger.LOG_USER|logger.LOG_DEBUG|logger.LOG_NOTICE|logger.LOG_ERR, "hkexsh") // nolint: errcheck,gosec
 	hkexnet.Init(dbg, "hkexsh", logger.LOG_USER|logger.LOG_DEBUG|logger.LOG_NOTICE|logger.LOG_ERR)
 	if dbg {
 		log.SetOutput(Log)
@@ -557,7 +575,7 @@ func main() {
 
 	if !gopt {
 		// See if we can log in via an auth token
-		u, _ := user.Current()
+		u, _ := user.Current() // nolint: gosec
 		ab, aerr := ioutil.ReadFile(fmt.Sprintf("%s/.hkexsh_id", u.HomeDir))
 		if aerr == nil {
 			idx := strings.Index(string(ab), remoteHost)
@@ -580,7 +598,7 @@ func main() {
 		// We must make the decision about interactivity before Dial()
 		// as it affects chaffing behaviour. 20180805
 		if gopt {
-			fmt.Fprintln(os.Stderr, "[requesting authtoken from server]")
+			fmt.Fprintln(os.Stderr, "[requesting authtoken from server]") // nolint: errcheck
 			op = []byte{'A'}
 			chaffFreqMin = 2
 			chaffFreqMax = 10
@@ -621,7 +639,7 @@ func main() {
 		fmt.Println(err)
 		panic(err)
 	}
-	defer conn.Close()
+	defer conn.Close() // nolint: errcheck
 	// From this point on, conn is a secure encrypted channel
 
 	// Set stdin in raw mode if it's an interactive session
@@ -636,7 +654,7 @@ func main() {
 			}
 			// #gv:s/label=\"main\$1\"/label=\"deferRestore\"/
 			// TODO:.gv:main:1:deferRestore
-			defer func() { _ = hkexsh.Restore(int(os.Stdin.Fd()), oldState) }() // Best effort.
+			defer func() { _ = hkexsh.Restore(int(os.Stdin.Fd()), oldState) }() // nolint: errcheck,gosec
 		} else {
 			log.Println("NOT A TTY")
 		}
@@ -657,20 +675,23 @@ func main() {
 
 	// Set up session params and send over to server
 	rec := hkexsh.NewSession(op, []byte(uname), []byte(remoteHost), []byte(os.Getenv("TERM")), []byte(cmdStr), []byte(authCookie), 0)
-	sendSessionParams(&conn, rec)
+	sendErr := sendSessionParams(&conn, rec)
+	if sendErr != nil {
+		log.Fatal(sendErr)
+	}
 
 	//Security scrub
-	authCookie = ""
+	authCookie = "" // nolint: ineffassign
 	runtime.GC()
 
 	// Read auth reply from server
 	authReply := make([]byte, 1) // bool: 0 = fail, 1 = pass
 	_, err = conn.Read(authReply)
 	if err != nil {
-		fmt.Fprintln(os.Stderr, "Error reading auth reply")
+		fmt.Fprintln(os.Stderr, "Error reading auth reply") // nolint: errcheck
 		rec.SetStatus(255)
 	} else if authReply[0] == 0 {
-		fmt.Fprintln(os.Stderr, rejectUserMsg())
+		fmt.Fprintln(os.Stderr, rejectUserMsg()) // nolint: errcheck
 		rec.SetStatus(255)
 	} else {
 
@@ -690,7 +711,7 @@ func main() {
 		keepAliveWorker := func() {
 			for {
 				time.Sleep(time.Duration(2) * time.Second)
-				conn.WritePacket([]byte{0, 0}, hkexnet.CSOTunKeepAlive)
+				conn.WritePacket([]byte{0, 0}, hkexnet.CSOTunKeepAlive) // nolint: errcheck,gosec
 			}
 		}
 		go keepAliveWorker()
@@ -700,17 +721,17 @@ func main() {
 
 			doShellMode(isInteractive, &conn, oldState, rec)
 		} else { // copyMode
-			s, _ := doCopyMode(&conn, pathIsDest, fileArgs, rec)
+			s, _ := doCopyMode(&conn, pathIsDest, fileArgs, rec) // nolint: errcheck,gosec
 			rec.SetStatus(s)
 		}
 
 		if rec.Status() != 0 {
-			fmt.Fprintln(os.Stderr, "Session exited with status:", rec.Status())
+			fmt.Fprintln(os.Stderr, "Session exited with status:", rec.Status()) // nolint: errcheck
 		}
 	}
 
 	if oldState != nil {
-		_ = hkexsh.Restore(int(os.Stdin.Fd()), oldState) // Best effort.
+		_ = hkexsh.Restore(int(os.Stdin.Fd()), oldState) // nolint: gosec
 	}
 	os.Exit(int(rec.Status()))
 }

hkexsh/termsize_linux.go

@@ -30,7 +30,7 @@ func handleTermResizes(conn *hkexnet.Conn) {
 				log.Println(err)
 			}
 			termSzPacket := fmt.Sprintf("%d %d", rows, cols)
-			conn.WritePacket([]byte(termSzPacket), hkexnet.CSOTermSize)
+			conn.WritePacket([]byte(termSzPacket), hkexnet.CSOTermSize) // nolint: errcheck,gosec
 		}
 	}()
 	ch <- syscall.SIGWINCH // Initial resize.

hkexshd/Makefile

@@ -1,4 +1,4 @@
-.PHONY: clean all vis
+.PHONY: clean all vis lint
 
 EXTPKGS = binary,bytes,crypto,encoding,errors,flag,fmt,internal,io,log,net,os,path,runtime,time,strings,sync,syscall
 EXE = $(notdir $(shell pwd))
@@ -13,3 +13,6 @@ vis:
 	go-callvis -skipbrowser -output hkexshd-vis -ignore $(EXTPKGS) -group pkg,type .
 	../fixup-gv.sh hkexshd.go && cat hkexshd-vis.gv | dot -Tpng -ohkexshd-vis.gv.png
 
+lint:
+	-gometalinter --deadline=60s | sort
+

hkexshd/hkexshd.go

@@ -34,16 +34,17 @@ import (
 )
 
 var (
-	Log *logger.Writer // reg. syslog output (no -d)
+	// Log - syslog output (with no -d)
+	Log *logger.Writer
 )
 
 /* -------------------------------------------------------------- */
 // Perform a client->server copy
-func runClientToServerCopyAs(who, ttype string, conn *hkexnet.Conn, fpath string, chaffing bool) (err error, exitStatus uint32) {
+func runClientToServerCopyAs(who, ttype string, conn *hkexnet.Conn, fpath string, chaffing bool) (exitStatus uint32, err error) {
-	u, _ := user.Lookup(who)
+	u, _ := user.Lookup(who) // nolint: gosec
 	var uid, gid uint32
-	fmt.Sscanf(u.Uid, "%d", &uid)
+	fmt.Sscanf(u.Uid, "%d", &uid) // nolint: gosec,errcheck
-	fmt.Sscanf(u.Gid, "%d", &gid)
+	fmt.Sscanf(u.Gid, "%d", &gid) // nolint: gosec,errcheck
 	log.Println("uid:", uid, "gid:", gid)
 
 	// Need to clear server's env and set key vars of the
@@ -54,9 +55,9 @@ func runClientToServerCopyAs(who, ttype string, conn *hkexnet.Conn, fpath string
 	// of client shell window used to run client.
 	// Investigate -- rlm 2018-01-26)
 	os.Clearenv()
-	os.Setenv("HOME", u.HomeDir)
+	os.Setenv("HOME", u.HomeDir) // nolint: gosec,errcheck
-	os.Setenv("TERM", ttype)
+	os.Setenv("TERM", ttype) // nolint: gosec,errcheck
-	os.Setenv("HKEXSH", "1")
+	os.Setenv("HKEXSH", "1") // nolint: gosec,errcheck
 
 	var c *exec.Cmd
 	cmdName := "/bin/tar"
@@ -74,7 +75,7 @@ func runClientToServerCopyAs(who, ttype string, conn *hkexnet.Conn, fpath string
 	// When args are passed in exec() format, no quoting is required
 	// (as this isn't input from a shell) (right? -rlm 20180823)
 	//cmdArgs := []string{"-x", "-C", destDir, `--xform=s#.*/\(.*\)#\1#`}
-	c = exec.Command(cmdName, cmdArgs...)
+	c = exec.Command(cmdName, cmdArgs...) // nolint: gosec
 
 	c.Dir = destDir
 
@@ -128,7 +129,7 @@ func runClientToServerCopyAs(who, ttype string, conn *hkexnet.Conn, fpath string
 				// an ExitStatus() method with the same signature.
 				if status, ok := exiterr.Sys().(syscall.WaitStatus); ok {
 					exitStatus = uint32(status.ExitStatus())
-					err = errors.New("cmd returned nonzero status")
+					//err = errors.New("cmd returned nonzero status")
 					log.Printf("Exit Status: %d\n", exitStatus)
 				}
 			}
@@ -139,11 +140,15 @@ func runClientToServerCopyAs(who, ttype string, conn *hkexnet.Conn, fpath string
 }
 
 // Perform a server->client copy
-func runServerToClientCopyAs(who, ttype string, conn *hkexnet.Conn, srcPath string, chaffing bool) (err error, exitStatus uint32) {
+func runServerToClientCopyAs(who, ttype string, conn *hkexnet.Conn, srcPath string, chaffing bool) (exitStatus uint32, err error) {
-	u, _ := user.Lookup(who)
+	u, err := user.Lookup(who)
+	if err != nil {
+		exitStatus = 1
+		return
+	}
 	var uid, gid uint32
-	fmt.Sscanf(u.Uid, "%d", &uid)
+	_, _ = fmt.Sscanf(u.Uid, "%d", &uid) // nolint: gosec
-	fmt.Sscanf(u.Gid, "%d", &gid)
+	_, _ = fmt.Sscanf(u.Gid, "%d", &gid) // nolint: gosec
 	log.Println("uid:", uid, "gid:", gid)
 
 	// Need to clear server's env and set key vars of the
@@ -154,9 +159,9 @@ func runServerToClientCopyAs(who, ttype string, conn *hkexnet.Conn, srcPath stri
 	// of client shell window used to run client.
 	// Investigate -- rlm 2018-01-26)
 	os.Clearenv()
-	os.Setenv("HOME", u.HomeDir)
+	_ = os.Setenv("HOME", u.HomeDir) // nolint: gosec
-	os.Setenv("TERM", ttype)
+	_ = os.Setenv("TERM", ttype)     // nolint: gosec
-	os.Setenv("HKEXSH", "1")
+	_ = os.Setenv("HKEXSH", "1")     // nolint: gosec
 
 	var c *exec.Cmd
 	cmdName := "/bin/tar"
@@ -167,7 +172,7 @@ func runServerToClientCopyAs(who, ttype string, conn *hkexnet.Conn, srcPath stri
 	srcDir, srcBase := path.Split(srcPath)
 	cmdArgs := []string{"-cz", "-C", srcDir, "-f", "-", srcBase}
 
-	c = exec.Command(cmdName, cmdArgs...)
+	c = exec.Command(cmdName, cmdArgs...) // nolint: gosec
 
 	//If os.Clearenv() isn't called by server above these will be seen in the
 	//client's session env.
@@ -197,40 +202,44 @@ func runServerToClientCopyAs(who, ttype string, conn *hkexnet.Conn, srcPath stri
 	err = c.Start() // returns immediately
 	if err != nil {
 		log.Printf("Command finished with error: %v", err)
-		return err, hkexnet.CSEExecFail // !?
+		return hkexnet.CSEExecFail, err // !?
-	} else {
+	}
-		if err := c.Wait(); err != nil {
+	if err := c.Wait(); err != nil {
-			//fmt.Println("*** c.Wait() done ***")
+		//fmt.Println("*** c.Wait() done ***")
-			if exiterr, ok := err.(*exec.ExitError); ok {
+		if exiterr, ok := err.(*exec.ExitError); ok {
-				// The program has exited with an exit code != 0
+			// The program has exited with an exit code != 0
 
-				// This works on both Unix and Windows. Although package
+			// This works on both Unix and Windows. Although package
-				// syscall is generally platform dependent, WaitStatus is
+			// syscall is generally platform dependent, WaitStatus is
-				// defined for both Unix and Windows and in both cases has
+			// defined for both Unix and Windows and in both cases has
-				// an ExitStatus() method with the same signature.
+			// an ExitStatus() method with the same signature.
-				if status, ok := exiterr.Sys().(syscall.WaitStatus); ok {
+			if status, ok := exiterr.Sys().(syscall.WaitStatus); ok {
-					exitStatus = uint32(status.ExitStatus())
+				exitStatus = uint32(status.ExitStatus())
-					if len(stdErrBuffer.Bytes()) > 0 {
+				if len(stdErrBuffer.Bytes()) > 0 {
-						log.Print(stdErrBuffer)
+					log.Print(stdErrBuffer)
-					}
-					log.Printf("Exit Status: %d", exitStatus)
 				}
+				log.Printf("Exit Status: %d", exitStatus)
 			}
 		}
-		//fmt.Println("*** server->client cp finished ***")
-		return
 	}
+	//fmt.Println("*** server->client cp finished ***")
+	return
 }
 
 // Run a command (via default shell) as a specific user
 //
 // Uses ptys to support commands which expect a terminal.
-func runShellAs(who, ttype string, cmd string, interactive bool, conn *hkexnet.Conn, chaffing bool) (err error, exitStatus uint32) {
+// nolint: gocyclo
+func runShellAs(who, ttype string, cmd string, interactive bool, conn *hkexnet.Conn, chaffing bool) (exitStatus uint32, err error) {
 	var wg sync.WaitGroup
-	u, _ := user.Lookup(who)
+	u, err := user.Lookup(who)
+	if err != nil {
+		exitStatus = 1
+		return
+	}
 	var uid, gid uint32
-	fmt.Sscanf(u.Uid, "%d", &uid)
+	_, _ = fmt.Sscanf(u.Uid, "%d", &uid) // nolint: gosec
-	fmt.Sscanf(u.Gid, "%d", &gid)
+	_, _ = fmt.Sscanf(u.Gid, "%d", &gid) // nolint: gosec
 	log.Println("uid:", uid, "gid:", gid)
 
 	// Need to clear server's env and set key vars of the
@@ -241,15 +250,15 @@ func runShellAs(who, ttype string, cmd string, interactive bool, conn *hkexnet.C
 	// of client shell window used to run client.
 	// Investigate -- rlm 2018-01-26)
 	os.Clearenv()
-	os.Setenv("HOME", u.HomeDir)
+	_ = os.Setenv("HOME", u.HomeDir) // nolint: gosec
-	os.Setenv("TERM", ttype)
+	_ = os.Setenv("TERM", ttype)     // nolint: gosec
-	os.Setenv("HKEXSH", "1")
+	_ = os.Setenv("HKEXSH", "1")     // nolint: gosec
 
 	var c *exec.Cmd
 	if interactive {
-		c = exec.Command("/bin/bash", "-i", "-l")
+		c = exec.Command("/bin/bash", "-i", "-l") // nolint: gosec
 	} else {
-		c = exec.Command("/bin/bash", "-c", cmd)
+		c = exec.Command("/bin/bash", "-c", cmd) // nolint: gosec
 	}
 	//If os.Clearenv() isn't called by server above these will be seen in the
 	//client's session env.
@@ -264,11 +273,11 @@ func runShellAs(who, ttype string, cmd string, interactive bool, conn *hkexnet.C
 	// Start the command with a pty.
 	ptmx, err := pty.Start(c) // returns immediately with ptmx file
 	if err != nil {
-		return err, hkexnet.CSEPtyExecFail
+		return hkexnet.CSEPtyExecFail, err
 	}
 	// Make sure to close the pty at the end.
 	// #gv:s/label=\"runShellAs\$1\"/label=\"deferPtmxClose\"/
-	defer func() { _ = ptmx.Close() }() // Best effort.
+	defer func() { _ = ptmx.Close() }() // nolint: gosec
 
 	log.Printf("[%s]\n", cmd)
 	if err != nil {
@@ -279,7 +288,7 @@ func runShellAs(who, ttype string, cmd string, interactive bool, conn *hkexnet.C
 		go func() {
 			for sz := range conn.WinCh {
 				log.Printf("[Setting term size to: %v %v]\n", sz.Rows, sz.Cols)
-				pty.Setsize(ptmx, &pty.Winsize{Rows: sz.Rows, Cols: sz.Cols})
+				pty.Setsize(ptmx, &pty.Winsize{Rows: sz.Rows, Cols: sz.Cols}) // nolint: gosec,errcheck
 			}
 			log.Println("*** WinCh goroutine done ***")
 		}()
@@ -346,6 +355,8 @@ func runShellAs(who, ttype string, cmd string, interactive bool, conn *hkexnet.C
 	return
 }
 
+// GenAuthToken generates a pseudorandom auth token for a specific
+// user from a specific host to allow non-interactive logins.
 func GenAuthToken(who string, connhost string) string {
 	//tokenA, e := os.Hostname()
 	//if e != nil {
@@ -354,7 +365,7 @@ func GenAuthToken(who string, connhost string) string {
 	tokenA := connhost
 
 	tokenB := make([]byte, 64)
-	_, _ = rand.Read(tokenB)
+	_, _ = rand.Read(tokenB) // nolint: gosec
 	return fmt.Sprintf("%s:%s", tokenA, hex.EncodeToString(tokenB))
 }
 
@@ -363,6 +374,7 @@ func GenAuthToken(who string, connhost string) string {
 // server code, save for declaring 'hkex' rather than 'net'
 // Listener and Conns. The KEx and encrypt/decrypt is done within the type.
 // Compare to 'serverp.go' in this directory to see the equivalence.
+// TODO: reduce gocyclo
 func main() {
 	version := hkexsh.Version
 
@@ -395,7 +407,7 @@ func main() {
 		}
 	}
 
-	Log, _ = logger.New(logger.LOG_DAEMON|logger.LOG_DEBUG|logger.LOG_NOTICE|logger.LOG_ERR, "hkexshd")
+	Log, _ = logger.New(logger.LOG_DAEMON|logger.LOG_DEBUG|logger.LOG_NOTICE|logger.LOG_ERR, "hkexshd") // nolint: gosec
 	hkexnet.Init(dbg, "hkexshd", logger.LOG_DAEMON|logger.LOG_DEBUG|logger.LOG_NOTICE|logger.LOG_ERR)
 	if dbg {
 		log.SetOutput(Log)
@@ -411,17 +423,17 @@ func main() {
 			sig := <-exitCh
 			switch sig.String() {
 			case "terminated":
-				logger.LogNotice(fmt.Sprintf("[Got signal: %s]", sig))
+				logger.LogNotice(fmt.Sprintf("[Got signal: %s]", sig)) // nolint: gosec,errcheck
 				signal.Reset()
-				syscall.Kill(0, syscall.SIGTERM)
+				syscall.Kill(0, syscall.SIGTERM) // nolint: gosec,errcheck
 			case "interrupt":
-				logger.LogNotice(fmt.Sprintf("[Got signal: %s]", sig))
+				logger.LogNotice(fmt.Sprintf("[Got signal: %s]", sig)) // nolint: gosec,errcheck
 				signal.Reset()
-				syscall.Kill(0, syscall.SIGINT)
+				syscall.Kill(0, syscall.SIGINT) // nolint: gosec,errcheck
 			case "hangup":
-				logger.LogNotice(fmt.Sprintf("[Got signal: %s - nop]", sig))
+				logger.LogNotice(fmt.Sprintf("[Got signal: %s - nop]", sig)) // nolint:gosec,errcheck
 			default:
-				logger.LogNotice(fmt.Sprintf("[Got signal: %s - ignored]", sig))
+				logger.LogNotice(fmt.Sprintf("[Got signal: %s - ignored]", sig)) // nolint: gosec,errcheck
 			}
 		}
 	}()
@@ -432,7 +444,7 @@ func main() {
 	if err != nil {
 		log.Fatal(err)
 	}
-	defer l.Close()
+	defer l.Close() // nolint: errcheck
 
 	log.Println("Serving on", laddr)
 	for {
@@ -452,7 +464,7 @@ func main() {
 			// The loop then returns to accepting, so that
 			// multiple connections may be served concurrently.
 			go func(hc *hkexnet.Conn) (e error) {
-				defer hc.Close()
+				defer hc.Close() // nolint: errcheck
 
 				//We use io.ReadFull() here to guarantee we consume
 				//just the data we want for the hkexsh.Session, and no more.
@@ -469,7 +481,7 @@ func main() {
 					return err
 				}
 
-				tmp := make([]byte, len1, len1)
+				tmp := make([]byte, len1)
 				_, err = io.ReadFull(hc, tmp)
 				if err != nil {
 					log.Println("[Bad hkexsh.Session.Op]")
@@ -477,7 +489,7 @@ func main() {
 				}
 				rec.SetOp(tmp)
 
-				tmp = make([]byte, len2, len2)
+				tmp = make([]byte, len2)
 				_, err = io.ReadFull(hc, tmp)
 				if err != nil {
 					log.Println("[Bad hkexsh.Session.Who]")
@@ -485,7 +497,7 @@ func main() {
 				}
 				rec.SetWho(tmp)
 
-				tmp = make([]byte, len3, len3)
+				tmp = make([]byte, len3)
 				_, err = io.ReadFull(hc, tmp)
 				if err != nil {
 					log.Println("[Bad hkexsh.Session.ConnHost]")
@@ -493,7 +505,7 @@ func main() {
 				}
 				rec.SetConnHost(tmp)
 
-				tmp = make([]byte, len4, len4)
+				tmp = make([]byte, len4)
 				_, err = io.ReadFull(hc, tmp)
 				if err != nil {
 					log.Println("[Bad hkexsh.Session.TermType]")
@@ -501,7 +513,7 @@ func main() {
 				}
 				rec.SetTermType(tmp)
 
-				tmp = make([]byte, len5, len5)
+				tmp = make([]byte, len5)
 				_, err = io.ReadFull(hc, tmp)
 				if err != nil {
 					log.Println("[Bad hkexsh.Session.Cmd]")
@@ -509,7 +521,7 @@ func main() {
 				}
 				rec.SetCmd(tmp)
 
-				tmp = make([]byte, len6, len6)
+				tmp = make([]byte, len6)
 				_, err = io.ReadFull(hc, tmp)
 				if err != nil {
 					log.Println("[Bad hkexsh.Session.AuthCookie]")
@@ -533,10 +545,10 @@ func main() {
 
 				// Tell client if auth was valid
 				if valid {
-					hc.Write([]byte{1})
+					hc.Write([]byte{1}) // nolint: gosec,errcheck
 				} else {
-					logger.LogNotice(fmt.Sprintln("Invalid user", string(rec.Who())))
+					logger.LogNotice(fmt.Sprintln("Invalid user", string(rec.Who()))) // nolint: errcheck,gosec
-					hc.Write([]byte{0}) // ? required?
+					hc.Write([]byte{0}) // nolint: gosec,errcheck
 					return
 				}
 
@@ -546,15 +558,15 @@ func main() {
 					// Generate automated login token
 					addr := hc.RemoteAddr()
 					hname := goutmp.GetHost(addr.String())
-					logger.LogNotice(fmt.Sprintf("[Generating autologin token for [%s@%s]]\n", rec.Who(), hname))
+					logger.LogNotice(fmt.Sprintf("[Generating autologin token for [%s@%s]]\n", rec.Who(), hname)) // nolint: gosec,errcheck
 					token := GenAuthToken(string(rec.Who()), string(rec.ConnHost()))
 					tokenCmd := fmt.Sprintf("echo \"%s\" | tee -a ~/.hkexsh_id", token)
-					runErr, cmdStatus := runShellAs(string(rec.Who()), string(rec.TermType()), tokenCmd, false, hc, chaffEnabled)
+					cmdStatus, runErr := runShellAs(string(rec.Who()), string(rec.TermType()), tokenCmd, false, hc, chaffEnabled)
 					// Returned hopefully via an EOF or exit/logout;
 					// Clear current op so user can enter next, or EOF
 					rec.SetOp([]byte{0})
 					if runErr != nil {
-						logger.LogErr(fmt.Sprintf("[Error generating autologin token for %s@%s]\n", rec.Who(), hname))
+						logger.LogErr(fmt.Sprintf("[Error generating autologin token for %s@%s]\n", rec.Who(), hname)) // nolint: gosec,errcheck
 					} else {
 						log.Printf("[Autologin token generation completed for %s@%s, status %d]\n", rec.Who(), hname, cmdStatus)
 						hc.SetStatus(hkexnet.CSOType(cmdStatus))
@@ -563,34 +575,34 @@ func main() {
 					// Non-interactive command
 					addr := hc.RemoteAddr()
 					hname := goutmp.GetHost(addr.String())
-					logger.LogNotice(fmt.Sprintf("[Running command for [%s@%s]]\n", rec.Who(), hname))
+					logger.LogNotice(fmt.Sprintf("[Running command for [%s@%s]]\n", rec.Who(), hname)) // nolint: gosec,errcheck
-					runErr, cmdStatus := runShellAs(string(rec.Who()), string(rec.TermType()), string(rec.Cmd()), false, hc, chaffEnabled)
+					cmdStatus, runErr := runShellAs(string(rec.Who()), string(rec.TermType()), string(rec.Cmd()), false, hc, chaffEnabled)
 					// Returned hopefully via an EOF or exit/logout;
 					// Clear current op so user can enter next, or EOF
 					rec.SetOp([]byte{0})
 					if runErr != nil {
-						logger.LogErr(fmt.Sprintf("[Error spawning cmd for %s@%s]\n", rec.Who(), hname))
+						logger.LogErr(fmt.Sprintf("[Error spawning cmd for %s@%s]\n", rec.Who(), hname)) // nolint: gosec,errcheck
 					} else {
-						logger.LogNotice(fmt.Sprintf("[Command completed for %s@%s, status %d]\n", rec.Who(), hname, cmdStatus))
+						logger.LogNotice(fmt.Sprintf("[Command completed for %s@%s, status %d]\n", rec.Who(), hname, cmdStatus)) // nolint: gosec,errcheck
 						hc.SetStatus(hkexnet.CSOType(cmdStatus))
 					}
 				} else if rec.Op()[0] == 's' {
 					// Interactive session
 					addr := hc.RemoteAddr()
 					hname := goutmp.GetHost(addr.String())
-					logger.LogNotice(fmt.Sprintf("[Running shell for [%s@%s]]\n", rec.Who(), hname))
+					logger.LogNotice(fmt.Sprintf("[Running shell for [%s@%s]]\n", rec.Who(), hname)) // nolint: gosec,errcheck
 
 					utmpx := goutmp.Put_utmp(string(rec.Who()), hname)
 					defer func() { goutmp.Unput_utmp(utmpx) }()
 					goutmp.Put_lastlog_entry("hkexsh", string(rec.Who()), hname)
-					runErr, cmdStatus := runShellAs(string(rec.Who()), string(rec.TermType()), string(rec.Cmd()), true, hc, chaffEnabled)
+					cmdStatus, runErr := runShellAs(string(rec.Who()), string(rec.TermType()), string(rec.Cmd()), true, hc, chaffEnabled)
 					// Returned hopefully via an EOF or exit/logout;
 					// Clear current op so user can enter next, or EOF
 					rec.SetOp([]byte{0})
 					if runErr != nil {
-						Log.Err(fmt.Sprintf("[Error spawning shell for %s@%s]\n", rec.Who(), hname))
+						Log.Err(fmt.Sprintf("[Error spawning shell for %s@%s]\n", rec.Who(), hname)) // nolint: gosec,errcheck
 					} else {
-						logger.LogNotice(fmt.Sprintf("[Shell completed for %s@%s, status %d]\n", rec.Who(), hname, cmdStatus))
+						logger.LogNotice(fmt.Sprintf("[Shell completed for %s@%s, status %d]\n", rec.Who(), hname, cmdStatus)) // nolint: gosec,errcheck
 						hc.SetStatus(hkexnet.CSOType(cmdStatus))
 					}
 				} else if rec.Op()[0] == 'D' {
@@ -598,15 +610,15 @@ func main() {
 					log.Printf("[Client->Server copy]\n")
 					addr := hc.RemoteAddr()
 					hname := goutmp.GetHost(addr.String())
-					logger.LogNotice(fmt.Sprintf("[Running copy for [%s@%s]]\n", rec.Who(), hname))
+					logger.LogNotice(fmt.Sprintf("[Running copy for [%s@%s]]\n", rec.Who(), hname)) // nolint: gosec,errcheck
-					runErr, cmdStatus := runClientToServerCopyAs(string(rec.Who()), string(rec.TermType()), hc, string(rec.Cmd()), chaffEnabled)
+					cmdStatus, runErr := runClientToServerCopyAs(string(rec.Who()), string(rec.TermType()), hc, string(rec.Cmd()), chaffEnabled)
 					// Returned hopefully via an EOF or exit/logout;
 					// Clear current op so user can enter next, or EOF
 					rec.SetOp([]byte{0})
 					if runErr != nil {
-						logger.LogErr(fmt.Sprintf("[Error running cp for %s@%s]\n", rec.Who(), hname))
+						logger.LogErr(fmt.Sprintf("[Error running cp for %s@%s]\n", rec.Who(), hname)) // nolint: gosec,errcheck
 					} else {
-						logger.LogNotice(fmt.Sprintf("[Command completed for %s@%s, status %d]\n", rec.Who(), hname, cmdStatus))
+						logger.LogNotice(fmt.Sprintf("[Command completed for %s@%s, status %d]\n", rec.Who(), hname, cmdStatus)) // nolint: gosec,errcheck
 					}
 					hc.SetStatus(hkexnet.CSOType(cmdStatus))
 
@@ -614,32 +626,32 @@ func main() {
 					s := make([]byte, 4)
 					binary.BigEndian.PutUint32(s, cmdStatus)
 					log.Printf("** cp writing closeStat %d at Close()\n", cmdStatus)
-					hc.WritePacket(s, hkexnet.CSOExitStatus)
+					hc.WritePacket(s, hkexnet.CSOExitStatus) // nolint: gosec,errcheck
 				} else if rec.Op()[0] == 'S' {
 					// File copy (src) operation - server copy to client
 					log.Printf("[Server->Client copy]\n")
 					addr := hc.RemoteAddr()
 					hname := goutmp.GetHost(addr.String())
-					logger.LogNotice(fmt.Sprintf("[Running copy for [%s@%s]]\n", rec.Who(), hname))
+					logger.LogNotice(fmt.Sprintf("[Running copy for [%s@%s]]\n", rec.Who(), hname)) // nolint: gosec,errcheck
-					runErr, cmdStatus := runServerToClientCopyAs(string(rec.Who()), string(rec.TermType()), hc, string(rec.Cmd()), chaffEnabled)
+					cmdStatus, runErr := runServerToClientCopyAs(string(rec.Who()), string(rec.TermType()), hc, string(rec.Cmd()), chaffEnabled)
-					// Returned hopefully via an EOF or exit/logout;
+					if runErr != nil {
+						logger.LogErr(fmt.Sprintf("[Error spawning cp for %s@%s]\n", rec.Who(), hname)) // nolint: gosec,errcheck
+					} else {
+						// Returned hopefully via an EOF or exit/logout;
+						logger.LogNotice(fmt.Sprintf("[Command completed for %s@%s, status %d]\n", rec.Who(), hname, cmdStatus)) // nolint: gosec,errcheck
+					}
 					// Clear current op so user can enter next, or EOF
 					rec.SetOp([]byte{0})
-					if runErr != nil {
-						logger.LogErr(fmt.Sprintf("[Error spawning cp for %s@%s]\n", rec.Who(), hname))
-					} else {
-						logger.LogNotice(fmt.Sprintf("[Command completed for %s@%s, status %d]\n", rec.Who(), hname, cmdStatus))
-					}
 					hc.SetStatus(hkexnet.CSOType(cmdStatus))
 					//fmt.Println("Waiting for EOF from other end.")
 					//_, _ = hc.Read(nil /*ackByte*/)
 					//fmt.Println("Got remote end ack.")
 				} else {
-					logger.LogErr(fmt.Sprintln("[Bad hkexsh.Session]"))
+					logger.LogErr(fmt.Sprintln("[Bad hkexsh.Session]")) // nolint: gosec,errcheck
 				}
 				return
-			}(&conn)
+			}(&conn) // nolint: errcheck
 		} // Accept() success
 	} //endfor
-	logger.LogNotice(fmt.Sprintln("[Exiting]"))
+	//logger.LogNotice(fmt.Sprintln("[Exiting]")) // nolint: gosec,errcheck
 }

logger/Makefile

@@ -1,4 +1,4 @@
-.PHONY: clean all
+.PHONY: clean all lint
 
 EXE = $(notdir $(shell pwd))
 
@@ -8,3 +8,5 @@ all:
 clean:
 	$(RM) $(EXE) $(EXE).exe
 
+lint:
+	gometalinter --deadline 60s | sort

logger/logger_linux.go

@@ -1,17 +1,20 @@
 // +build linux
-//
+
-// Wrapper around UNIX syslog, so that it also may be wrapped
+// Package logger is a wrapper around UNIX syslog, so that it also may
-// with something else for Windows (Sadly, the stdlib log/syslog
+// be wrapped with something else for Windows (Sadly, the stdlib log/syslog
-// is frozen, and there is no Window implementation.)
+// is frozen, and there is no Windows implementation.)
 package logger
 
 import (
 	sl "log/syslog"
 )
 
+// Priority is the logger priority
 type Priority = sl.Priority
+// Writer is a syslog Writer
 type Writer = sl.Writer
 
+// nolint: golint
 const (
 	// Severity.
 
@@ -27,6 +30,7 @@ const (
 	LOG_DEBUG
 )
 
+// nolint: golint
 const (
 	// Facility.
 
@@ -62,39 +66,59 @@ var (
 	l *sl.Writer
 )
 
+// New returns a new log Writer.
 func New(flags Priority, tag string) (w *Writer, e error) {
-	w, e = sl.New(sl.Priority(flags), tag)
+	w, e = sl.New(flags, tag)
 	l = w
 	return w, e
 }
 
+// Alert returns a log Alert error
 func Alert(s string) error {
 		return l.Alert(s)
 }
+
+// LogClose closes the log Writer.
 func LogClose() error {
 		return l.Close()
 }
+
+// LogCrit returns a log Alert error
 func LogCrit(s string) error {
 		return l.Crit(s)
 }
+
+// LogDebug returns a log Debug error
 func LogDebug(s string) error {
 		return l.Debug(s)
 }
+
+// LogEmerg returns a log Emerg error
 func LogEmerg(s string) error {
 		return l.Emerg(s)
 }
+
+// LogErr returns a log Err error
 func LogErr(s string) error {
 		return l.Err(s)
 }
+
+// LogInfo returns a log Info error
 func LogInfo(s string) error {
 		return l.Info(s)
 }
+
+// LogNotice returns a log Notice error
 func LogNotice(s string) error {
 		return l.Notice(s)
 }
+
+// LogWarning returns a log Warning error
 func LogWarning(s string) error {
 		return l.Warning(s)
 }
+
+// LogWrite writes to the logger at default level
 func LogWrite(b []byte) (int, error) {
 		return l.Write(b)
 }

termmode_unix.go

@@ -20,6 +20,7 @@ const ioctlReadTermios = unix.TCGETS
 const ioctlWriteTermios = unix.TCSETS
 
 // From github.com/golang/crypto/blob/master/ssh/terminal/util.go
+
 // State contains the state of a terminal.
 type State struct {
 	termios unix.Termios
@@ -87,7 +88,7 @@ func ReadPassword(fd int) ([]byte, error) {
 	}
 
 	defer func() {
-		unix.IoctlSetTermios(fd, ioctlWriteTermios, termios)
+		_ = unix.IoctlSetTermios(fd, ioctlWriteTermios, termios) // nolint: gosec
 	}()
 
 	return readPasswordLine(passwordReader(fd))