Fixed errors in copy scatter/gather logic. Added block-chunking to hc.Write() to allow

writes of larger data blocks
TODO: copies of files > hc.Read() block size fails w/incomplete tarfile (last partial block
likely incorrectly written or client exits before data is flushed?)

hkexnet/hkexnet.go

@@ -394,7 +394,7 @@ func (hc Conn) Read(b []byte) (n int, err error) {
 			}
 		}
 
-		if payloadLen > 16384 {
+		if payloadLen > 8192 {
 			log.Printf("[Insane payloadLen:%v]\n", payloadLen)
 			hc.Close()
 			return 1, errors.New("Insane payloadLen")
@@ -499,13 +499,15 @@ func (hc Conn) WritePacket(b []byte, op byte) (n int, err error) {
 	// Would be nice to determine if the mutex scope
 	// could be tightened.
 	hc.m.Lock()
-	{
-		log.Printf("  :>ptext:\r\n%s\r\n", hex.Dump(b))
-
+	for uint32(len(b)) > 0 {
 		payloadLen = uint32(len(b))
+		if payloadLen > 8192 {
+			payloadLen = 8192
+		}
+		log.Printf("  :>ptext:\r\n%s\r\n", hex.Dump(b[0:payloadLen]))
 
 		// Calculate hmac on payload
-		hc.wm.Write(b)
+		hc.wm.Write(b[0:payloadLen])
 		hmacOut = hc.wm.Sum(nil)[0:4]
 
 		log.Printf("  (%04x> HMAC(o):%s\r\n", payloadLen, hex.EncodeToString(hmacOut))
@@ -514,14 +516,13 @@ func (hc Conn) WritePacket(b []byte, op byte) (n int, err error) {
 		// The StreamWriter acts like a pipe, forwarding whatever is
 		// written to it through the cipher, encrypting as it goes
 		ws := &cipher.StreamWriter{S: hc.w, W: &wb}
-		_, err = ws.Write(b)
+		_, err = ws.Write(b[0:payloadLen])
 		if err != nil {
 			panic(err)
 		}
 		log.Printf("  ->ctext:\r\n%s\r\n", hex.Dump(wb.Bytes()))
 		
 		ctrlStatOp := op
-
 		err = binary.Write(hc.c, binary.BigEndian, &ctrlStatOp)
 		if err == nil {
 			// Write hmac LSB, payloadLen followed by payload
@@ -533,6 +534,7 @@ func (hc Conn) WritePacket(b []byte, op byte) (n int, err error) {
 				}
 			}
 		}
+		b = b[payloadLen:]
 	}
 	hc.m.Unlock()
 

hkexsh/hkexsh.go

@@ -17,6 +17,7 @@ import (
 	"os/exec"
 	"os/user"
 	"path"
+	"path/filepath"
 	"runtime"
 	"strings"
 	"sync"
@@ -107,19 +108,29 @@ func doCopyMode(conn *hkexnet.Conn, remoteDest bool, files string, rec *cmdSpec)
 		//os.Setenv("TERM", "vt102") // TODO: server or client option?
 
 		cmdName := "/bin/tar"
-		cmdArgs := []string{"-cz", "-f", "/dev/stdout"}
+		cmdArgs := []string{"-c", "-f", "/dev/stdout"}
 		files = strings.TrimSpace(files)
 		// Awesome fact: tar actually can take multiple -C args, and
 		// changes to the dest dir *as it sees each one*. This enables
 		// its use below, where clients can send scattered sets of source
-		// files and dirs to be extraced to a single dest dir server-side,
+		// files and dirs to be extracted to a single dest dir server-side,
 		// whilst preserving the subtrees of dirs on the other side. :)
 		// Eg., tar -c -f /dev/stdout -C /dirA fileInA -C /some/where/dirB fileInB /foo/dirC
 		// packages fileInA, fileInB, and dirC at a single toplevel in the tar.
 		// The tar authors are/were real smarties :)
+		//
+		// This is the 'scatter/gather' logic to allow specification of
+		// files and dirs in different trees to be deposited in a single
+		// remote destDir.
 		for _, v := range strings.Split(files, " ") {
+			v, _ = filepath.Abs(v)
 			dirTmp, fileTmp := path.Split(v)
-			cmdArgs = append(cmdArgs, "-C", dirTmp, fileTmp)
+			if dirTmp == "" {
+				cmdArgs = append(cmdArgs, fileTmp)
+			} else {
+				cmdArgs = append(cmdArgs, "-C", dirTmp, fileTmp)
+			}
+
 			//cmdArgs = append(cmdArgs, v)
 		}
 
@@ -171,7 +182,7 @@ func doCopyMode(conn *hkexnet.Conn, remoteDest bool, files string, rec *cmdSpec)
 		cmdName := "/bin/tar"
 		destPath := files
 
-		cmdArgs := []string{"-xz", "-C", destPath}
+		cmdArgs := []string{"-x", "-C", destPath}
 		fmt.Printf("[%v %v]\n", cmdName, cmdArgs)
 		// NOTE the lack of quotes around --xform option's sed expression.
 		// When args are passed in exec() format, no quoting is required

hkexshd/hkexshd.go

@@ -67,7 +67,7 @@ func runClientToServerCopyAs(who string, conn hkexnet.Conn, fpath string, chaffi
 		destDir = path.Join(u.HomeDir, fpath)
 	}
 
-	cmdArgs := []string{"-xz", "-C", destDir}
+	cmdArgs := []string{"-x", "-C", destDir}
 
 	// NOTE the lack of quotes around --xform option's sed expression.
 	// When args are passed in exec() format, no quoting is required
@@ -146,7 +146,7 @@ func runServerToClientCopyAs(who string, conn hkexnet.Conn, srcPath string, chaf
 	}
 
 	srcDir, srcBase := path.Split(srcPath)
-	cmdArgs := []string{"-cz", "-C", srcDir, "-f", "-", srcBase}
+	cmdArgs := []string{"-c", "-C", srcDir, "-f", "-", srcBase}
 
 	c = exec.Command(cmdName, cmdArgs...)