Various improvements and bug fixes

.gitignore

@@ -14,6 +14,7 @@
 *log
 Vagrantfile
 trunk
+trunks
 trunks_amd64
 
 # Dependency directories (remove the comment below to include it)

README.md

@@ -71,11 +71,13 @@ COMMANDS:
    help, h  Shows a list of commands or help for one command
 
 GLOBAL OPTIONS:
-   --config FILE  Load configuration from FILE (default: not set)
-   --flush        Flush IPTABLES table mangle and clear all TC rules (default: false)
-   --acm          Activate the ACM simulation (default: not activated)
-   --qos          Process traffic using QoS (default: not activated)
-   --help, -h     show help (default: false)
+   --config FILE                   Load configuration from FILE (default: not set)
+   --logs value                    Log path for the log file (default: not set)
+   --flush                         Flush IPTABLES table mangle and clear all TC rules (default: false)
+   --acm                           Activate the ACM simulation (default: not activated)
+   --qos                           Process traffic using QoS (default: not activated)
+   --disable-kernel-version-check  Disable check for bugged kernel versions (default: kernel version check enabled)
+   --help, -h                      show help (default: false)
 
 ```
 
@@ -149,4 +151,7 @@ cd container
 docker-compose up -d
 ```
 
-You still must configure the routes inside the client and server containers.
+You still must configure the routes inside the client and server containers.
+
+## Known issues
+Some versions of the kernel are known to crash when offset delay is enabled. As a protection, offset delay is by default disabled if you are running on affected versions. You can bypass protection by using the flag `--disable-kernel-version-check`, but this is NOT recommended. See [this issue](https://github.com/shynuu/trunks/issues/6) for details.

bash-completion/completions/trunks

@@ -0,0 +1,21 @@
+#! /bin/bash
+
+: ${PROG:=$(basename ${BASH_SOURCE})}
+
+_cli_bash_autocomplete() {
+  if [[ "${COMP_WORDS[0]}" != "source" ]]; then
+    local cur opts base
+    COMPREPLY=()
+    cur="${COMP_WORDS[COMP_CWORD]}"
+    if [[ "$cur" == "-"* ]]; then
+      opts=$( ${COMP_WORDS[@]:0:$COMP_CWORD} ${cur} --generate-bash-completion )
+    else
+      opts=$( ${COMP_WORDS[@]:0:$COMP_CWORD} --generate-bash-completion )
+    fi
+    COMPREPLY=( $(compgen -W "${opts}" -- ${cur}) )
+    return 0
+  fi
+}
+
+complete -o bashdefault -o default -o nospace -F _cli_bash_autocomplete $PROG
+unset PROG

main.go

@@ -4,22 +4,33 @@ import (
 	"fmt"
 	"log"
 	"os"
+	"os/signal"
+	"syscall"
 
 	trunks "github.com/shynuu/trunks/runtime"
-
 	"github.com/urfave/cli/v2"
 )
 
+// Initialize signals handling
+func initSignals() {
+	cancelChan := make(chan os.Signal, 1)
+	signal.Notify(cancelChan, syscall.SIGTERM, syscall.SIGINT)
+	func(_ os.Signal) {}(<-cancelChan)
+	os.Exit(0)
+}
+
 func main() {
 	var config string
 	var flush bool = false
 	var acm bool = false
 	var qos bool = false
+	var disable_kernel_version_check = false
 	var logs string
 
 	app := &cli.App{
-		Name:  "trunks",
-		Usage: "a simple DVB-S2/DVB-RCS2 simulator",
+		Name:                 "trunks",
+		Usage:                "a simple DVB-S2/DVB-RCS2 simulator",
+		EnableBashCompletion: true,
 		Authors: []*cli.Author{
 			{Name: "Youssouf Drif"},
 		},
@@ -55,27 +66,33 @@ func main() {
 				Destination: &qos,
 				DefaultText: "not activated",
 			},
+			&cli.BoolFlag{
+				Name:        "disable-kernel-version-check",
+				Usage:       "Disable check for bugged kernel versions",
+				Destination: &disable_kernel_version_check,
+				DefaultText: "kernel version check enabled",
+			},
 		},
 		Action: func(c *cli.Context) error {
-			err := trunks.InitTrunks(config, qos, logs)
+			trunksConfig, err := trunks.InitTrunks(config, qos, logs, acm, disable_kernel_version_check)
 			if err != nil {
 				fmt.Println("Init error, exiting...")
 				os.Exit(1)
 			}
 
 			if flush {
-				err = trunks.FlushTables()
+				err = trunksConfig.FlushTables()
 				if err != nil {
 					fmt.Println("Impossible to flush tables, exiting...")
 					os.Exit(1)
 				}
 			}
 
-			trunks.Run(acm)
+			trunksConfig.Run()
 			return nil
 		},
 	}
-
+	go initSignals()
 	err := app.Run(os.Args)
 	if err != nil {
 		log.Fatal(err)

runtime/acm.go

@@ -10,33 +10,33 @@ import (
 )
 
 // RunACM simulate the used by the DVB-S2/RCS2 system
-func RunACM(qos bool) {
-	if Trunks.CurrentACM == nil || Trunks.ACMCounter >= Trunks.CurrentACM.Duration {
+func (t *TrunksConfig) RunACM(qos bool) {
+	if t.CurrentACM == nil || t.ACMCounter >= t.CurrentACM.Duration {
 		log.Println("Changing link capacity")
-		var l = len(Trunks.ACMList)
+		var l = len(t.ACMList)
 		rand.Seed(time.Now().UnixNano())
 		var index int = rand.Intn(l)
-		Trunks.CurrentACM = Trunks.ACMList[index]
+		t.CurrentACM = t.ACMList[index]
 
 		var forward string
 		var retun string
 
 		if qos {
-			forward = fmt.Sprintf("%dmbit", int64(math.Round(Trunks.Bandwidth.Forward*Trunks.CurrentACM.Weight))-1)
-			retun = fmt.Sprintf("%dmbit", int64(math.Round(Trunks.Bandwidth.Return*Trunks.CurrentACM.Weight))-1)
-			runTC("class", "change", "dev", Trunks.NIC.GW, "parent", "1:0", "classid", "1:20", "htb", "rate", retun, "prio", "1")
-			runTC("class", "change", "dev", Trunks.NIC.ST, "parent", "1:0", "classid", "1:20", "htb", "rate", forward, "prio", "1")
+			forward = fmt.Sprintf("%dmbit", int64(math.Round(t.Bandwidth.Forward*t.CurrentACM.Weight))-1)
+			retun = fmt.Sprintf("%dmbit", int64(math.Round(t.Bandwidth.Return*t.CurrentACM.Weight))-1)
+			runTC("class", "change", "dev", t.NIC.GW, "parent", "1:0", "classid", "1:20", "htb", "rate", retun, "prio", "1")
+			runTC("class", "change", "dev", t.NIC.ST, "parent", "1:0", "classid", "1:20", "htb", "rate", forward, "prio", "1")
 
 		} else {
-			forward = fmt.Sprintf("%dmbit", int64(math.Round(Trunks.Bandwidth.Forward*Trunks.CurrentACM.Weight)))
-			retun = fmt.Sprintf("%dmbit", int64(math.Round(Trunks.Bandwidth.Return*Trunks.CurrentACM.Weight)))
-			runTC("class", "change", "dev", Trunks.NIC.GW, "parent", "1:0", "classid", "1:1", "htb", "rate", retun)
-			runTC("class", "change", "dev", Trunks.NIC.ST, "parent", "1:0", "classid", "1:1", "htb", "rate", forward)
+			forward = fmt.Sprintf("%dmbit", int64(math.Round(t.Bandwidth.Forward*t.CurrentACM.Weight)))
+			retun = fmt.Sprintf("%dmbit", int64(math.Round(t.Bandwidth.Return*t.CurrentACM.Weight)))
+			runTC("class", "change", "dev", t.NIC.GW, "parent", "1:0", "classid", "1:1", "htb", "rate", retun)
+			runTC("class", "change", "dev", t.NIC.ST, "parent", "1:0", "classid", "1:1", "htb", "rate", forward)
 		}
 		log.Println("Setting the forward link bandwidth at", forward)
 		log.Println("Setting the return link bandwidth at", retun)
 
-		Trunks.ACMCounter = 0
+		t.ACMCounter = 0
 	}
-	Trunks.ACMCounter++
+	t.ACMCounter++
 }

runtime/config.go

@@ -8,17 +8,17 @@ import (
 )
 
 // ParseConf read the yaml file and populate the Config instancce
-func ParseConf(file string) error {
+func ParseConf(file string) (*TrunksConfig, error) {
+	var trunksConfig *TrunksConfig
 	path, err := filepath.Abs(file)
 	yamlFile, err := ioutil.ReadFile(path)
 	if err != nil {
-		return err
+		return nil, err
 	}
-	err = yaml.Unmarshal(yamlFile, &Trunks)
-	if err != nil {
-		return err
+	if err := yaml.Unmarshal(yamlFile, &trunksConfig); err != nil {
+		return nil, err
 	}
-	return nil
+	return trunksConfig, nil
 }
 
 // Interfaces struct
@@ -47,13 +47,15 @@ type ACM struct {
 
 // TrunksConfig struct
 type TrunksConfig struct {
-	NIC        NIC       `yaml:"nic"`
-	Bandwidth  Bandwidth `yaml:"bandwidth"`
-	Delay      Delay     `yaml:"delay"`
-	ACMList    []*ACM    `yaml:"acm"`
-	QoS        bool
-	Logs       string
-	ACMCounter int
-	ACMIndex   int
-	CurrentACM *ACM
+	NIC                NIC       `yaml:"nic"`
+	Bandwidth          Bandwidth `yaml:"bandwidth"`
+	Delay              Delay     `yaml:"delay"`
+	ACMList            []*ACM    `yaml:"acm"`
+	QoS                bool
+	Logs               string
+	KernelVersionCheck bool
+	ACMEnabled         bool
+	ACMCounter         int
+	ACMIndex           int
+	CurrentACM         *ACM
 }

runtime/init.go

@@ -21,10 +21,10 @@ func Exists(path string) (bool, error) {
 }
 
 // CheckInterfaces checks if the interfaces exist
-func CheckInterfaces(st string, gw string) error {
+func (t *TrunksConfig) CheckInterfaces() error {
 	path := "/sys/class/net/%s/operstate"
-	ifST := fmt.Sprintf(path, st)
-	ifGW := fmt.Sprintf(path, gw)
+	ifST := fmt.Sprintf(path, t.NIC.ST)
+	ifGW := fmt.Sprintf(path, t.NIC.GW)
 	var err1, err2 error
 	existST, _ := Exists(ifST)
 	if !existST {
@@ -44,9 +44,9 @@ func CheckInterfaces(st string, gw string) error {
 	return nil
 }
 
-func FindInterfaces() error {
-	ip_st := Trunks.NIC.ST
-	ip_gw := Trunks.NIC.GW
+func (t *TrunksConfig) FindInterfaces() error {
+	ip_st := t.NIC.ST
+	ip_gw := t.NIC.GW
 	ifaces, err := net.Interfaces()
 	if err != nil {
 		log.Printf("Error reading interfaces: %+v\n", err.Error())
@@ -61,24 +61,24 @@ func FindInterfaces() error {
 		for _, a := range addrs {
 			switch v := a.(type) {
 			case *net.IPNet:
-				if v.IP.To4().String() == Trunks.NIC.GW {
-					Trunks.NIC.GW = i.Name
+				if v.IP.To4().String() == t.NIC.GW {
+					t.NIC.GW = i.Name
 				}
-				if v.IP.To4().String() == Trunks.NIC.ST {
-					Trunks.NIC.ST = i.Name
+				if v.IP.To4().String() == t.NIC.ST {
+					t.NIC.ST = i.Name
 				}
 			}
 
 		}
 	}
 
 	var err1, err2 error
-	if ip_st == Trunks.NIC.ST {
+	if ip_st == t.NIC.ST {
 		err1 = errors.New("[L3] Interface for ST not found")
 		log.Println(err1.Error())
 	}
 
-	if ip_gw == Trunks.NIC.GW {
+	if ip_gw == t.NIC.GW {
 		err2 = errors.New("[L3] Interface for GW not found")
 		log.Println(err2.Error())
 	}
@@ -91,17 +91,21 @@ func FindInterfaces() error {
 }
 
 // InitTrunks initialize the trunks module
-func InitTrunks(file string, qos bool, logs string) error {
-	err := ParseConf(file)
+func InitTrunks(file string, qos bool, logs string, acm bool, disable_kernel_version_check bool) (*TrunksConfig, error) {
+	t, err := ParseConf(file)
 	if err != nil {
-		return err
+		return nil, err
 	}
-	err = CheckInterfaces(Trunks.NIC.ST, Trunks.NIC.GW)
-	if err != nil {
+	if err := t.CheckInterfaces(); err != nil {
 		log.Println("Interfaces configuration by IP")
-		err = FindInterfaces()
+		if err := t.FindInterfaces(); err != nil {
+			return nil, err
+		}
 	}
-	Trunks.QoS = qos
-	Trunks.Logs = logs
-	return err
+
+	t.QoS = qos
+	t.Logs = logs
+	t.ACMEnabled = acm
+	t.KernelVersionCheck = !disable_kernel_version_check
+	return t, nil
 }