Update README.md

snmplog: only format the log file name, not the whole path

.travis.yml

@@ -1,6 +1,6 @@
 language: go
 go:
-    - 1.6
+    - 1.9
 before_install:
     - go get github.com/mattn/goveralls
     - go get golang.org/x/tools/cmd/cover

Dockerfile

@@ -1,8 +1,11 @@
-FROM golang:alpine
+FROM golang:alpine as builder
 MAINTAINER xtaci <daniel820313@gmail.com>
 RUN apk update && \
     apk upgrade && \
     apk add git
 RUN go get -ldflags "-X main.VERSION=$(date -u +%Y%m%d) -s -w" github.com/xtaci/kcptun/client && go get -ldflags "-X main.VERSION=$(date -u +%Y%m%d) -s -w" github.com/xtaci/kcptun/server
+
+FROM alpine:3.6
+COPY --from=builder /go/bin /bin
 EXPOSE 29900/udp
 EXPOSE 12948

README.md

@@ -21,23 +21,48 @@
 
 <img src="kcptun.png" alt="kcptun" height="300px"/>
 
+> *kcptun maintains a single website — [github.com/xtaci/kcptun](https://github.com/xtaci/kcptun). Any websites other than [github.com/xtaci/kcptun](https://github.com/xtaci/kcptun) are not endorsed by xtaci. kcptun won't publish anything on any social media.*
+
+> *KCP discussion QQ group: 364933586, KCP integration, tuning, network transmission and related technical discussions.*
+
 ### QuickStart
 
-Download precompiled [Releases](https://github.com/xtaci/kcptun/releases).
+Increase the number of open files on your server, as:
+
+`ulimit -n 65535`, or write it in `~/.bashrc`.
+
+Increase the OS UDP buffers to improve performance, as:
+
+```
+net.core.rmem_max=26214400
+net.core.rmem_default=26214400
+```
+
+You can also increase the per-socket buffer by adding parameter(default 4MB):
+```
+-sockbuf 16777217
+```
+increasing this would work for most of the old model CPUs.
+
+
+Download a corresponding precompiled [Releases](https://github.com/xtaci/kcptun/releases).
 
 ```
 KCP Client: ./client_darwin_amd64 -r "KCP_SERVER_IP:4000" -l ":8388" -mode fast2
 KCP Server: ./server_linux_amd64 -t "TARGET_IP:8388" -l ":4000" -mode fast2
 ```
-The above commands will establish port forwarding for 8388/tcp as:
+The above commands will establish port forwarding channel for 8388/tcp as:
 
-Application -> KCP Client(8388/tcp) -> KCP Server(4000/udp) -> Server(8388/tcp) 
+> Application -> **KCP Client(8388/tcp) -> KCP Server(4000/udp)** -> Target Server(8388/tcp) 
+
+which tunnels the original connection:
+
+> Application -> Target Server(8388/tcp) 
 
 ### Install from source
 
 ```
-$go get -u github.com/xtaci/kcptun/client
-$go get -u github.com/xtaci/kcptun/server
+$go get -u github.com/xtaci/kcptun/...
 ```
 
 All precompiled releases are genereated from `build-release.sh` script.
@@ -52,7 +77,8 @@ All precompiled releases are genereated from `build-release.sh` script.
 
 > **Q: I have a high speed network link, how to reach the maximum bandwidth?**        
 
-> **A:** Increase `-rcvwnd` on KCP Client and `-sndwnd` on KCP Server **simultaneously & gradually**, the mininum one decides the maximum transfer rate of the link, as `wnd * mtu / rtt`; Then try downloading something and to see if it meets your requirements.
+> **A:** Increase `-rcvwnd` on KCP Client and `-sndwnd` on KCP Server **simultaneously & gradually**, the mininum one decides the maximum transfer rate of the link, as `wnd * mtu / rtt`; Then try downloading something and to see if it meets your requirements. 
+(mtu is adjustable by `-mtu`)
 
 #### Improving Latency
 
@@ -66,7 +92,7 @@ All precompiled releases are genereated from `build-release.sh` script.
 
 > *fast3 > fast2 > fast > normal > default*
 
--
+
 
 ### Expert Tuning Guide
 
@@ -85,7 +111,7 @@ USAGE:
    client_darwin_amd64 [global options] command [command options] [arguments...]
 
 VERSION:
-   20170120
+   20180922
 
 COMMANDS:
      help, h  Shows a list of commands or help for one command
@@ -94,10 +120,11 @@ GLOBAL OPTIONS:
    --localaddr value, -l value      local listen address (default: ":12948")
    --remoteaddr value, -r value     kcp server address (default: "vps:29900")
    --key value                      pre-shared secret between client and server (default: "it's a secrect") [$KCPTUN_KEY]
-   --crypt value                    aes, aes-128, aes-192, salsa20, blowfish, twofish, cast5, 3des, tea, xtea, xor, none (default: "aes")
-   --mode value                     profiles: fast3, fast2, fast, normal (default: "fast")
+   --crypt value                    aes, aes-128, aes-192, salsa20, blowfish, twofish, cast5, 3des, tea, xtea, xor, sm4, none (default: "aes")
+   --mode value                     profiles: fast3, fast2, fast, normal, manual (default: "fast")
    --conn value                     set num of UDP connections to server (default: 1)
    --autoexpire value               set auto expiration time(in seconds) for a single UDP connection, 0 to disable (default: 0)
+   --scavengettl value              set how long an expired connection can live(in sec), -1 to disable (default: 600)
    --mtu value                      set maximum transmission unit for UDP packets (default: 1350)
    --sndwnd value                   set send window size(num of packets) (default: 128)
    --rcvwnd value                   set receive window size(num of packets) (default: 512)
@@ -105,9 +132,12 @@ GLOBAL OPTIONS:
    --parityshard value, --ps value  set reed-solomon erasure coding - parityshard (default: 3)
    --dscp value                     set DSCP(6bit) (default: 0)
    --nocomp                         disable compression
+   --sockbuf value                  (default: 4194304)
+   --keepalive value                (default: 10)
    --snmplog value                  collect snmp to file, aware of timeformat in golang, like: ./snmp-20060102.log
    --snmpperiod value               snmp collect period, in seconds (default: 60)
    --log value                      specify a log file to output, default goes to stderr
+   --quiet                          to suppress the 'stream open/close' messages
    -c value                         config from json file, which will override the command from shell
    --help, -h                       show help
    --version, -v                    print the version
@@ -120,7 +150,7 @@ USAGE:
    server_darwin_amd64 [global options] command [command options] [arguments...]
 
 VERSION:
-   20170120
+   20180922
 
 COMMANDS:
      help, h  Shows a list of commands or help for one command
@@ -129,8 +159,8 @@ GLOBAL OPTIONS:
    --listen value, -l value         kcp server listen address (default: ":29900")
    --target value, -t value         target server address (default: "127.0.0.1:12948")
    --key value                      pre-shared secret between client and server (default: "it's a secrect") [$KCPTUN_KEY]
-   --crypt value                    aes, aes-128, aes-192, salsa20, blowfish, twofish, cast5, 3des, tea, xtea, xor, none (default: "aes")
-   --mode value                     profiles: fast3, fast2, fast, normal (default: "fast")
+   --crypt value                    aes, aes-128, aes-192, salsa20, blowfish, twofish, cast5, 3des, tea, xtea, xor, sm4, none (default: "aes")
+   --mode value                     profiles: fast3, fast2, fast, normal, manual (default: "fast")
    --mtu value                      set maximum transmission unit for UDP packets (default: 1350)
    --sndwnd value                   set send window size(num of packets) (default: 1024)
    --rcvwnd value                   set receive window size(num of packets) (default: 1024)
@@ -138,9 +168,13 @@ GLOBAL OPTIONS:
    --parityshard value, --ps value  set reed-solomon erasure coding - parityshard (default: 3)
    --dscp value                     set DSCP(6bit) (default: 0)
    --nocomp                         disable compression
+   --sockbuf value                  (default: 4194304)
+   --keepalive value                (default: 10)
    --snmplog value                  collect snmp to file, aware of timeformat in golang, like: ./snmp-20060102.log
    --snmpperiod value               snmp collect period, in seconds (default: 60)
+   --pprof                          start profiling server on :6060
    --log value                      specify a log file to output, default goes to stderr
+   --quiet                          to suppress the 'stream open/close' messages
    -c value                         config from json file, which will override the command from shell
    --help, -h                       show help
    --version, -v                    print the version
@@ -154,7 +188,7 @@ It is able to detect and correct multiple symbol errors. By adding t check symbo
 
 ![reed-solomon](rs.png)
 
-Setting parameters of RS-Code with ```-datashard m -parityshard n``` on both KCP Client & KCP Server.
+Setting parameters of RS-Code with ```-datashard m -parityshard n``` on **BOTH** KCP Client & KCP Server **MUST** be **IDENTICAL**.
 
 #### DSCP
 
@@ -194,7 +228,7 @@ BenchmarkSalsa20-4     	  300000	      4998 ns/op
 
 #### Memory Control
 
-Routers, mobile devices are sensitive to memory consumption; by setting GOGC environment(eg: GOGC=20) will lower memory consumption.
+Routers, mobile devices are susceptible to memory consumption; by setting GOGC environment(eg: GOGC=20) will make the garbage collector to recycle faster.
 Reference: https://blog.golang.org/go15gc
 
 #### Compression
@@ -212,7 +246,7 @@ kcptun has builtin snappy algorithms for compressing streams:
 
 Compression may save bandwidth for **PLAINTEXT** data, such as HTTP data.
 
-Compression is enabled by default, you can disable it by setting ```-nocomp``` on both KCP Client & KCP Server.
+Compression is enabled by default, you can disable it by setting ```-nocomp``` on **BOTH** KCP Client & KCP Server **MUST** be **IDENTICAL**.
 
 #### SNMP
 
@@ -254,6 +288,17 @@ https://github.com/skywind3000/kcp/blob/master/README.en.md#protocol-configurati
 
 Low-level KCP configuration can be altered by using manual mode like above, make sure you really **UNDERSTAND** what these means before doing **ANY** manual settings.
 
+
+### Identical Parmeters
+
+The parameters below **MUST** be **IDENTICAL** on **BOTH** side:
+
+1. -key
+1. -crypt
+1. -nocomp
+1. -datashard
+1. -parityshard
+
 ### References
 
 1. https://github.com/skywind3000/kcp -- KCP - A Fast and Reliable ARQ Protocol.
@@ -271,3 +316,10 @@ Low-level KCP configuration can be altered by using manual mode like above, make
 1. http://http2.github.io/ -- What is HTTP/2?
 1. http://www.lartc.org/ -- Linux Advanced Routing & Traffic Control
 1. https://en.wikipedia.org/wiki/Noisy-channel_coding_theorem -- Noisy channel coding theorem
+1. https://play.google.com/store/apps/details?id=com.k17game.k3 -- Battle Zone - Earth 2048, an online strategy game using kcp.
+
+### Donate via Ethereum(ETH)
+
+Address: 0x2e4b43ab3d0983da282592571eef61ae5e60f726 , Or scan here:
+
+<img src="0x2e4b43ab3d0983da282592571eef61ae5e60f726.png" alt="kcptun" height="100px" /> 

build-release.sh

@@ -47,10 +47,10 @@ tar -zcf kcptun-linux-arm-$VERSION.tar.gz client_linux_arm* server_linux_arm*
 $sum kcptun-linux-arm-$VERSION.tar.gz
 
 #MIPS32LE
-env CGO_ENABLED=0 GOOS=linux GOARCH=mipsle go build -ldflags "$LDFLAGS" -gcflags "$GCFLAGS" -o client_linux_mipsle github.com/xtaci/kcptun/client
-env CGO_ENABLED=0 GOOS=linux GOARCH=mipsle go build -ldflags "$LDFLAGS" -gcflags "$GCFLAGS" -o server_linux_mipsle github.com/xtaci/kcptun/server
-env CGO_ENABLED=0 GOOS=linux GOARCH=mips go build -ldflags "$LDFLAGS" -gcflags "$GCFLAGS" -o client_linux_mips github.com/xtaci/kcptun/client
-env CGO_ENABLED=0 GOOS=linux GOARCH=mips go build -ldflags "$LDFLAGS" -gcflags "$GCFLAGS" -o server_linux_mips github.com/xtaci/kcptun/server
+env CGO_ENABLED=0 GOOS=linux GOARCH=mipsle GOMIPS=softfloat go build -ldflags "$LDFLAGS" -gcflags "$GCFLAGS" -o client_linux_mipsle github.com/xtaci/kcptun/client
+env CGO_ENABLED=0 GOOS=linux GOARCH=mipsle GOMIPS=softfloat go build -ldflags "$LDFLAGS" -gcflags "$GCFLAGS" -o server_linux_mipsle github.com/xtaci/kcptun/server
+env CGO_ENABLED=0 GOOS=linux GOARCH=mips GOMIPS=softfloat go build -ldflags "$LDFLAGS" -gcflags "$GCFLAGS" -o client_linux_mips github.com/xtaci/kcptun/client
+env CGO_ENABLED=0 GOOS=linux GOARCH=mips GOMIPS=softfloat go build -ldflags "$LDFLAGS" -gcflags "$GCFLAGS" -o server_linux_mips github.com/xtaci/kcptun/server
 
 if $UPX; then upx -9 client_linux_mips* server_linux_mips*;fi
 tar -zcf kcptun-linux-mipsle-$VERSION.tar.gz client_linux_mipsle server_linux_mipsle

client/config.go

@@ -32,6 +32,7 @@ type Config struct {
 	Log          string `json:"log"`
 	SnmpLog      string `json:"snmplog"`
 	SnmpPeriod   int    `json:"snmpperiod"`
+	Quiet        bool   `json:"quiet"`
 }
 
 func parseJSONConfig(config *Config, path string) error {

client/main.go

@@ -18,6 +18,8 @@ import (
 	"github.com/urfave/cli"
 	kcp "github.com/xtaci/kcp-go"
 	"github.com/xtaci/smux"
+
+	"path/filepath"
 )
 
 var (
@@ -55,9 +57,12 @@ func newCompStream(conn net.Conn) *compStream {
 	return c
 }
 
-func handleClient(sess *smux.Session, p1 io.ReadWriteCloser) {
-	log.Println("stream opened")
-	defer log.Println("stream closed")
+func handleClient(sess *smux.Session, p1 io.ReadWriteCloser, quiet bool) {
+	if !quiet {
+		log.Println("stream opened")
+		defer log.Println("stream closed")
+	}
+
 	defer p1.Close()
 	p2, err := sess.OpenStream()
 	if err != nil {
@@ -67,10 +72,12 @@ func handleClient(sess *smux.Session, p1 io.ReadWriteCloser) {
 
 	// start tunnel
 	p1die := make(chan struct{})
-	go func() { io.Copy(p1, p2); close(p1die) }()
+	buf1 := make([]byte, 65535)
+	go func() { io.CopyBuffer(p1, p2, buf1); close(p1die) }()
 
 	p2die := make(chan struct{})
-	go func() { io.Copy(p2, p1); close(p2die) }()
+	buf2 := make([]byte, 65535)
+	go func() { io.CopyBuffer(p2, p1, buf2); close(p2die) }()
 
 	// wait for tunnel termination
 	select {
@@ -116,7 +123,7 @@ func main() {
 		cli.StringFlag{
 			Name:  "crypt",
 			Value: "aes",
-			Usage: "aes, aes-128, aes-192, salsa20, blowfish, twofish, cast5, 3des, tea, xtea, xor, none",
+			Usage: "aes, aes-128, aes-192, salsa20, blowfish, twofish, cast5, 3des, tea, xtea, xor, sm4, none",
 		},
 		cli.StringFlag{
 			Name:  "mode",
@@ -198,14 +205,14 @@ func main() {
 			Hidden: true,
 		},
 		cli.IntFlag{
-			Name:   "sockbuf",
-			Value:  4194304, // socket buffer size in bytes
-			Hidden: true,
+			Name:  "sockbuf",
+			Value: 4194304, // socket buffer size in bytes
+			Usage: "per-socket buffer in bytes",
 		},
 		cli.IntFlag{
-			Name:   "keepalive",
-			Value:  10, // nat keepalive interval in seconds
-			Hidden: true,
+			Name:  "keepalive",
+			Value: 10, // nat keepalive interval in seconds
+			Usage: "seconds between heartbeats",
 		},
 		cli.StringFlag{
 			Name:  "snmplog",
@@ -222,6 +229,10 @@ func main() {
 			Value: "",
 			Usage: "specify a log file to output, default goes to stderr",
 		},
+		cli.BoolFlag{
+			Name:  "quiet",
+			Usage: "to suppress the 'stream open/close' messages",
+		},
 		cli.StringFlag{
 			Name:  "c",
 			Value: "", // when the value is not empty, the config path must exists
@@ -255,6 +266,7 @@ func main() {
 		config.Log = c.String("log")
 		config.SnmpLog = c.String("snmplog")
 		config.SnmpPeriod = c.Int("snmpperiod")
+		config.Quiet = c.Bool("quiet")
 
 		if c.String("c") != "" {
 			err := parseJSONConfig(&config, c.String("c"))
@@ -286,9 +298,12 @@ func main() {
 		listener, err := net.ListenTCP("tcp", addr)
 		checkError(err)
 
+		log.Println("initiating key derivation")
 		pass := pbkdf2.Key([]byte(config.Key), []byte(SALT), 4096, 32, sha1.New)
 		var block kcp.BlockCrypt
 		switch config.Crypt {
+		case "sm4":
+			block, _ = kcp.NewSM4BlockCrypt(pass[:16])
 		case "tea":
 			block, _ = kcp.NewTEABlockCrypt(pass[:16])
 		case "xor":
@@ -333,6 +348,7 @@ func main() {
 		log.Println("scavengettl:", config.ScavengeTTL)
 		log.Println("snmplog:", config.SnmpLog)
 		log.Println("snmpperiod:", config.SnmpPeriod)
+		log.Println("quiet:", config.Quiet)
 
 		smuxConfig := smux.DefaultConfig()
 		smuxConfig.MaxReceiveBuffer = config.SockBuf
@@ -344,7 +360,7 @@ func main() {
 				return nil, errors.Wrap(err, "createConn()")
 			}
 			kcpconn.SetStreamMode(true)
-			kcpconn.SetWriteDelay(true)
+			kcpconn.SetWriteDelay(false)
 			kcpconn.SetNoDelay(config.NoDelay, config.Interval, config.Resend, config.NoCongestion)
 			kcpconn.SetWindowSize(config.SndWnd, config.RcvWnd)
 			kcpconn.SetMtu(config.MTU)
@@ -380,6 +396,7 @@ func main() {
 				if session, err := createConn(); err == nil {
 					return session
 				} else {
+					log.Println("re-connecting:", err)
 					time.Sleep(time.Second)
 				}
 			}
@@ -415,7 +432,7 @@ func main() {
 				muxes[idx].ttl = time.Now().Add(time.Duration(config.AutoExpire) * time.Second)
 			}
 
-			go handleClient(muxes[idx].session, p1)
+			go handleClient(muxes[idx].session, p1, config.Quiet)
 			rr++
 		}
 	}
@@ -464,7 +481,10 @@ func snmpLogger(path string, interval int) {
 	for {
 		select {
 		case <-ticker.C:
-			f, err := os.OpenFile(time.Now().Format(path), os.O_RDWR|os.O_CREATE|os.O_APPEND, 0666)
+			// split path into dirname and filename
+			logdir, logfile := filepath.Split(path)
+			// only format logfile
+			f, err := os.OpenFile(logdir+time.Now().Format(logfile), os.O_RDWR|os.O_CREATE|os.O_APPEND, 0666)
 			if err != nil {
 				log.Println(err)
 				return

server/config.go

@@ -30,6 +30,7 @@ type Config struct {
 	SnmpLog      string `json:"snmplog"`
 	SnmpPeriod   int    `json:"snmpperiod"`
 	Pprof        bool   `json:"pprof"`
+	Quiet        bool   `json:"quiet"`
 }
 
 func parseJSONConfig(config *Config, path string) error {

server/main.go

@@ -15,6 +15,8 @@ import (
 
 	"golang.org/x/crypto/pbkdf2"
 
+	"path/filepath"
+
 	"github.com/golang/snappy"
 	"github.com/urfave/cli"
 	kcp "github.com/xtaci/kcp-go"
@@ -81,22 +83,26 @@ func handleMux(conn io.ReadWriteCloser, config *Config) {
 			log.Println(err)
 			continue
 		}
-		go handleClient(p1, p2)
+		go handleClient(p1, p2, config.Quiet)
 	}
 }
 
-func handleClient(p1, p2 io.ReadWriteCloser) {
-	log.Println("stream opened")
-	defer log.Println("stream closed")
+func handleClient(p1, p2 io.ReadWriteCloser, quiet bool) {
+	if !quiet {
+		log.Println("stream opened")
+		defer log.Println("stream closed")
+	}
 	defer p1.Close()
 	defer p2.Close()
 
 	// start tunnel
 	p1die := make(chan struct{})
-	go func() { io.Copy(p1, p2); close(p1die) }()
+	buf1 := make([]byte, 65535)
+	go func() { io.CopyBuffer(p1, p2, buf1); close(p1die) }()
 
 	p2die := make(chan struct{})
-	go func() { io.Copy(p2, p1); close(p2die) }()
+	buf2 := make([]byte, 65535)
+	go func() { io.CopyBuffer(p2, p1, buf2); close(p2die) }()
 
 	// wait for tunnel termination
 	select {
@@ -142,7 +148,7 @@ func main() {
 		cli.StringFlag{
 			Name:  "crypt",
 			Value: "aes",
-			Usage: "aes, aes-128, aes-192, salsa20, blowfish, twofish, cast5, 3des, tea, xtea, xor, none",
+			Usage: "aes, aes-128, aes-192, salsa20, blowfish, twofish, cast5, 3des, tea, xtea, xor, sm4, none",
 		},
 		cli.StringFlag{
 			Name:  "mode",
@@ -209,14 +215,14 @@ func main() {
 			Hidden: true,
 		},
 		cli.IntFlag{
-			Name:   "sockbuf",
-			Value:  4194304, // socket buffer size in bytes
-			Hidden: true,
+			Name:  "sockbuf",
+			Value: 4194304, // socket buffer size in bytes
+			Usage: "per-socket buffer in bytes",
 		},
 		cli.IntFlag{
-			Name:   "keepalive",
-			Value:  10, // nat keepalive interval in seconds
-			Hidden: true,
+			Name:  "keepalive",
+			Value: 10, // nat keepalive interval in seconds
+			Usage: "seconds between heartbeats",
 		},
 		cli.StringFlag{
 			Name:  "snmplog",
@@ -237,6 +243,10 @@ func main() {
 			Value: "",
 			Usage: "specify a log file to output, default goes to stderr",
 		},
+		cli.BoolFlag{
+			Name:  "quiet",
+			Usage: "to suppress the 'stream open/close' messages",
+		},
 		cli.StringFlag{
 			Name:  "c",
 			Value: "", // when the value is not empty, the config path must exists
@@ -268,6 +278,7 @@ func main() {
 		config.SnmpLog = c.String("snmplog")
 		config.SnmpPeriod = c.Int("snmpperiod")
 		config.Pprof = c.Bool("pprof")
+		config.Quiet = c.Bool("quiet")
 
 		if c.String("c") != "" {
 			//Now only support json config file
@@ -295,9 +306,12 @@ func main() {
 		}
 
 		log.Println("version:", VERSION)
+		log.Println("initiating key derivation")
 		pass := pbkdf2.Key([]byte(config.Key), []byte(SALT), 4096, 32, sha1.New)
 		var block kcp.BlockCrypt
 		switch config.Crypt {
+		case "sm4":
+			block, _ = kcp.NewSM4BlockCrypt(pass[:16])
 		case "tea":
 			block, _ = kcp.NewTEABlockCrypt(pass[:16])
 		case "xor":
@@ -342,6 +356,7 @@ func main() {
 		log.Println("snmplog:", config.SnmpLog)
 		log.Println("snmpperiod:", config.SnmpPeriod)
 		log.Println("pprof:", config.Pprof)
+		log.Println("quiet:", config.Quiet)
 
 		if err := lis.SetDSCP(config.DSCP); err != nil {
 			log.Println("SetDSCP:", err)
@@ -362,7 +377,7 @@ func main() {
 			if conn, err := lis.AcceptKCP(); err == nil {
 				log.Println("remote address:", conn.RemoteAddr())
 				conn.SetStreamMode(true)
-				conn.SetWriteDelay(true)
+				conn.SetWriteDelay(false)
 				conn.SetNoDelay(config.NoDelay, config.Interval, config.Resend, config.NoCongestion)
 				conn.SetMtu(config.MTU)
 				conn.SetWindowSize(config.SndWnd, config.RcvWnd)
@@ -390,7 +405,10 @@ func snmpLogger(path string, interval int) {
 	for {
 		select {
 		case <-ticker.C:
-			f, err := os.OpenFile(time.Now().Format(path), os.O_RDWR|os.O_CREATE|os.O_APPEND, 0666)
+			// split path into dirname and filename
+			logdir, logfile := filepath.Split(path)
+			// only format logfile
+			f, err := os.OpenFile(logdir+time.Now().Format(logfile), os.O_RDWR|os.O_CREATE|os.O_APPEND, 0666)
 			if err != nil {
 				log.Println(err)
 				return