Add -tftp server

.travis.yml

@@ -2,6 +2,8 @@ language: go
 go:
 - 1.13.x
 before_install:
+- sudo apt-get -y install python3-pip python3-setuptools
+- pip3 install scapy
 - go get -u github.com/mattn/goveralls
 - go get -u github.com/golangci/golangci-lint/cmd/golangci-lint
 script:

Makefile

@@ -1,6 +1,6 @@
 export GOPRIVATE := code.cfops.it
 IMPORT_PATH := github.com/majek/slirpnetstack
-GOFLAGS=-ldflags=-compressdwarf=false
+GOFLAGS=-ldflags=-compressdwarf=false -gcflags=all="-N -l"
 
 bin/slirpnetstack: *.go go.mod
 	go build \

dhcp.go

@@ -0,0 +1,119 @@
+package main
+
+import (
+	"gvisor.dev/gvisor/pkg/tcpip"
+	"gvisor.dev/gvisor/pkg/tcpip/adapters/gonet"
+	"gvisor.dev/gvisor/pkg/tcpip/network/ipv4"
+	"gvisor.dev/gvisor/pkg/tcpip/stack"
+
+	"github.com/insomniacslk/dhcp/dhcpv4"
+	"github.com/insomniacslk/dhcp/dhcpv4/server4"
+	"github.com/sirupsen/logrus"
+
+	"github.com/coredhcp/coredhcp"
+	"github.com/coredhcp/coredhcp/config"
+	"github.com/coredhcp/coredhcp/handler"
+	"github.com/coredhcp/coredhcp/logger"
+
+	"github.com/coredhcp/coredhcp/plugins"
+	"github.com/coredhcp/coredhcp/plugins/dns"
+	"github.com/coredhcp/coredhcp/plugins/nbp"
+	rangepl "github.com/coredhcp/coredhcp/plugins/range"
+	"github.com/coredhcp/coredhcp/plugins/router"
+	"github.com/coredhcp/coredhcp/plugins/serverid"
+)
+
+var bootfilePlugin = plugins.Plugin{
+	Name:   "slirp.bootfile",
+	Setup4: bootfile_setup4,
+}
+
+var desiredPlugins = []*plugins.Plugin{
+	&dns.Plugin,
+	&rangepl.Plugin,
+	&router.Plugin,
+	&serverid.Plugin,
+	&nbp.Plugin,
+	&bootfilePlugin,
+}
+
+func bootfile_setup4(args ...string) (handler.Handler4, error) {
+	h := func(req, resp *dhcpv4.DHCPv4) (*dhcpv4.DHCPv4, bool) {
+		resp.BootFileName = args[0]
+		return resp, false
+	}
+	return h, nil
+}
+
+func setupDHCP(s *stack.Stack, state *State) error {
+	log := logger.GetLogger("plugins")
+	log.Logger.SetLevel(logrus.WarnLevel)
+	for _, plugin := range desiredPlugins {
+		if e := plugins.RegisterPlugin(plugin); e != nil {
+			return e
+		}
+	}
+
+	conf := config.New()
+	plugins := make([]*config.PluginConfig, 0)
+	plugins = append(plugins,
+		&config.PluginConfig{
+			Name: "range",
+			Args: []string{"/dev/null",
+				state.DHCPStart.String(), state.DHCPEnd.String(),
+				"24h"},
+		},
+		&config.PluginConfig{
+			Name: "dns",
+			Args: state.DHCPDns.servers,
+		},
+		&config.PluginConfig{
+			Name: "server_id",
+			Args: []string{state.Host.String()},
+		})
+	if !state.Restricted {
+		plugins = append(plugins,
+			&config.PluginConfig{
+				Name: "router",
+				Args: []string{state.Host.String()},
+			},
+		)
+	}
+	if state.DHCPNbp != "" {
+		plugins = append(plugins,
+			&config.PluginConfig{
+				Name: "nbp",
+				Args: []string{state.DHCPNbp},
+			},
+		)
+	}
+	if state.DHCPBootfile != "" {
+		plugins = append(plugins,
+			&config.PluginConfig{
+				Name: "slirp.bootfile",
+				Args: []string{state.DHCPBootfile},
+			},
+		)
+	}
+	conf.Server4 = &config.ServerConfig{
+		Plugins: plugins,
+	}
+
+	server := coredhcp.NewServer(conf)
+	if _, _, e := server.LoadPlugins(server.Config); e != nil {
+		return e
+	}
+
+	// no IP, this will catch broadcasted packets
+	addr := tcpip.FullAddress{1, "", dhcpv4.ServerPort}
+	if conn, e := gonet.DialUDP(s, &addr, nil, ipv4.ProtocolNumber); e != nil {
+		return e
+	} else if server4, e := server4.NewServer("", nil, server.MainHandler4, server4.WithConn(conn)); e != nil {
+		return e
+	} else {
+		server.Server4 = server4
+	}
+	go server.Server4.Serve()
+
+	return nil
+}

dnsconfig.go

@@ -0,0 +1,50 @@
+package main
+
+import (
+	"bufio"
+	"net"
+	"os"
+	"strings"
+)
+
+type dnsConfig struct {
+	servers    []string // server addresses
+	err        error    // any error that occurs during open of resolv.conf
+	unknownOpt bool     // anything unknown was encountered
+}
+
+// See resolv.conf(5) on a Linux machine.
+func dnsReadConfig(filename string) *dnsConfig {
+	conf := &dnsConfig{}
+
+	file, err := os.Open(filename)
+	if err != nil {
+		conf.err = err
+		return conf
+	}
+	defer file.Close()
+
+	scanner := bufio.NewScanner(file)
+	for scanner.Scan() {
+		line := scanner.Text()
+		if len(line) > 0 && (line[0] == ';' || line[0] == '#') {
+			// comment.
+			continue
+		}
+		f := strings.Fields(line)
+		if len(f) < 1 {
+			continue
+		}
+		switch f[0] {
+		case "nameserver":
+			if len(f) > 1 && len(conf.servers) < 3 { // small, but the standard limit
+				if net.ParseIP(f[1]) != nil {
+					conf.servers = append(conf.servers, f[1])
+				}
+			}
+		default:
+			conf.unknownOpt = true
+		}
+	}
+	return conf
+}

go.mod

@@ -4,8 +4,12 @@ go 1.13
 
 require (
 	github.com/cenkalti/backoff v2.2.1+incompatible // indirect
+	github.com/coredhcp/coredhcp v0.0.0-20200209180252-349f5927f59c
 	github.com/golang/protobuf v1.3.3 // indirect
+	github.com/insomniacslk/dhcp v0.0.0-20200210095418-45e5f320b2f0
 	github.com/opencontainers/runtime-spec v0.1.2-0.20171211145439-b2d941ef6a78
+	github.com/pin/tftp v2.1.0+incompatible
+	github.com/sirupsen/logrus v1.4.2
 	github.com/wadey/gocovmerge v0.0.0-20160331181800-b5bfa59ec0ad // indirect
 	golang.org/x/sys v0.0.0-20200202164722-d101bd2416d5
 	golang.org/x/time v0.0.0-20191024005414-555d28b269f0 // indirect