From 5eb7d4d1e635cecaa21747eac6209f659eb1531a Mon Sep 17 00:00:00 2001
From: Russ Magee <rmagee@gmail.com>
Date: Sun, 29 Jul 2018 00:48:42 -0700
Subject: [PATCH] Initial (buggy) support for 'fancy arg' style ala ssh: eg
 user@example.org:port:path

---
 hkexsh/hkexsh.go | 76 ++++++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 70 insertions(+), 6 deletions(-)

diff --git a/hkexsh/hkexsh.go b/hkexsh/hkexsh.go
index 4f9ca23..d68e877 100755
--- a/hkexsh/hkexsh.go
+++ b/hkexsh/hkexsh.go
@@ -34,7 +34,8 @@ type cmdSpec struct {
 }
 
 var (
-	wg sync.WaitGroup
+	wg      sync.WaitGroup
+	defPort = "2000"
 )
 
 // Get terminal size using 'stty' command
@@ -52,6 +53,53 @@ func GetSize() (cols, rows int, err error) {
 	return
 }
 
+func parseFancyEndpointArg(a []string, dp string) (user, host, port, path string) {
+	//TODO: Look for non-option fancyArg of syntax user@host:filespec to set -r,-t and -u
+	//  Consider: whether fancyArg is src or dst file depends on flag.Args() index;
+	//            fancyArg as last flag.Args() element denotes dstFile
+	//            fancyArg as not-last flag.Args() element denotes srcFile
+	//            * throw error if >1 fancyArgs are found in flags.Args()
+	var fancyUser, fancyHost, fancyPort, fancyPath string
+	for i, arg := range flag.Args() {
+		if strings.Contains(arg, ":") || strings.Contains(arg, "@") {
+			fancyArg := strings.Split(flag.Arg(i), "@")
+			var fancyHostPortPath []string
+			if len(fancyArg) < 2 {
+				//TODO: no user specified, use current
+				fancyUser = "[default:getUser]"
+				fancyHostPortPath = strings.Split(fancyArg[0], ":")
+			} else {
+				// user@....
+				fancyUser = fancyArg[0]
+				fancyHostPortPath = strings.Split(fancyArg[1], ":")
+			}
+
+			if len(fancyHostPortPath) > 2 {
+				// [user]@host[:port]:path
+				fancyPath = fancyHostPortPath[2]
+			}
+			if len(fancyHostPortPath) > 1 {
+				// [user]@host:port[:...] or [user]@host:path (default port)
+				fancyPort = fancyHostPortPath[1]
+			}
+			// [user]@host[:...[:...]]
+			fancyHost = fancyHostPortPath[0]
+
+			if fancyPort == "" {
+				fancyPort = dp
+			}
+
+			if fancyPath == "" {
+				fancyPath = "."
+			}
+
+			fmt.Println("fancyArgs: user:", fancyUser, "host:", fancyHost, "port:", fancyPort, "path:", fancyPath)
+			break // ignore multiple 'fancyArgs'
+		}
+	}
+	return fancyUser, fancyHost, fancyPort, fancyPath
+}
+
 // Demo of a simple client that dials up to a simple test server to
 // send data.
 //
@@ -90,29 +138,45 @@ func main() {
 	flag.BoolVar(&dbg, "d", false, "debug logging")
 	flag.StringVar(&cAlg, "c", "C_AES_256", "cipher [\"C_AES_256\" | \"C_TWOFISH_128\" | \"C_BLOWFISH_64\"]")
 	flag.StringVar(&hAlg, "m", "H_SHA256", "hmac [\"H_SHA256\"]")
-	flag.StringVar(&server, "s", "localhost:2000", "server hostname/address[:port]")
+	flag.StringVar(&server, "s", "localhost:"+defPort, "server hostname/address[:port]")
 	flag.StringVar(&altUser, "u", "", "specify alternate user")
 	flag.StringVar(&authCookie, "a", "", "auth cookie")
 	flag.BoolVar(&chaffEnabled, "e", true, "enabled chaff pkts (default true)")
 	flag.UintVar(&chaffFreqMin, "f", 100, "chaff pkt freq min (msecs)")
 	flag.UintVar(&chaffFreqMax, "F", 5000, "chaff pkt freq max (msecs)")
 	flag.UintVar(&chaffBytesMax, "B", 64, "chaff pkt size max (bytes)")
-	
+
 	// Find out what program we are (shell or copier)
 	myPath := strings.Split(os.Args[0], string(os.PathSeparator))
-	if myPath[len(myPath)-1] != "hkexcp" {
+	if myPath[len(myPath)-1] != "hkexcp" && myPath[len(myPath)-1] != "hkexcp.exe" {
 		// hkexsh accepts a command (-x) but not
 		// a srcpath (-r) or dstpath (-t)
 		flag.StringVar(&cmdStr, "x", "", "command to run (default empty - interactive shell)")
-		flag.Parse()
 	} else {
 		// hkexcp accepts srcpath (-r) and dstpath (-t), but not
 		// a command (-x)
 		flag.StringVar(&copySrc, "r", "", "copy srcpath")
 		flag.StringVar(&copyDst, "t", "", "copy dstpath")
 	}
+	flag.Parse()
 
-	if flag.NFlag() == 0 {
+	fancyUser, fancyHost, fancyPort, fancyPath := parseFancyEndpointArg(flag.Args(), defPort /* defPort */)
+	fmt.Println("fancyHost:", fancyHost)
+	if fancyUser != "" {
+		altUser = fancyUser
+	}
+	if fancyHost != "" {
+		server = fancyHost + ":" + fancyPort
+		fmt.Println("fancyHost sets server to", server)
+	}
+	if fancyPath != "" {
+		//TODO: srcPath or dstPath depends on other flag.Args
+		copyDst = fancyPath
+	}
+
+	fmt.Println("server finally is:", server)
+
+	if flag.NFlag() == 0 && server == "" {
 		flag.Usage()
 		os.Exit(0)
 	}