feat: implement tftp server

MODULE.bazel

@@ -11,7 +11,7 @@ go_sdk.download(version = "1.23.3")
 
 go_deps = use_extension("@bazel_gazelle//:extensions.bzl", "go_deps")
 go_deps.from_file(go_mod = "//:go.mod")
-use_repo(go_deps, "com_github_spf13_cobra")
+use_repo(go_deps, "com_github_pin_tftp_v3", "com_github_sirupsen_logrus", "com_github_spf13_cobra")
 
 ###############################################################################
 # RPM

go.mod

@@ -2,9 +2,15 @@ module toni.systems/goisoboot
 
 go 1.22.0
 
-require github.com/spf13/cobra v1.8.1
+require (
+	github.com/pin/tftp/v3 v3.1.0
+	github.com/sirupsen/logrus v1.9.3
+	github.com/spf13/cobra v1.8.1
+)
 
 require (
 	github.com/inconshreveable/mousetrap v1.1.0 // indirect
 	github.com/spf13/pflag v1.0.5 // indirect
+	golang.org/x/net v0.0.0-20200202094626-16171245cfb2 // indirect
+	golang.org/x/sys v0.0.0-20220715151400-c0bba94af5f8 // indirect
 )

go.sum

@@ -1,10 +1,31 @@
 github.com/cpuguy83/go-md2man/v2 v2.0.4/go.mod h1:tgQtvFlXSQOSOSIRvRPT7W67SCa46tRHOmNcaadrF8o=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/inconshreveable/mousetrap v1.1.0 h1:wN+x4NVGpMsO7ErUn/mUI3vEoE6Jt13X2s0bqwp9tc8=
 github.com/inconshreveable/mousetrap v1.1.0/go.mod h1:vpF70FUmC8bwa3OWnCshd2FqLfsEA9PFc4w1p2J65bw=
+github.com/pin/tftp/v3 v3.1.0 h1:rQaxd4pGwcAJnpId8zC+O2NX3B2/NscjDZQaqEjuE7c=
+github.com/pin/tftp/v3 v3.1.0/go.mod h1:xwQaN4viYL019tM4i8iecm++5cGxSqen6AJEOEyEI0w=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
+github.com/sirupsen/logrus v1.9.3 h1:dueUQJ1C2q9oE3F7wvmSGAaVtTmUizReu6fjN8uqzbQ=
+github.com/sirupsen/logrus v1.9.3/go.mod h1:naHLuLoDiP4jHNo9R0sCBMtWGeIprob74mVsIT4qYEQ=
 github.com/spf13/cobra v1.8.1 h1:e5/vxKd/rZsfSJMUX1agtjeTDf+qv1/JdBF8gg5k9ZM=
 github.com/spf13/cobra v1.8.1/go.mod h1:wHxEcudfqmLYa8iTfL+OuZPbBZkmvliBWKIezN3kD9Y=
 github.com/spf13/pflag v1.0.5 h1:iy+VFUOCP1a+8yFto/drg2CJ5u0yRoB7fZw3DKv/JXA=
 github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
+github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/testify v1.7.0 h1:nwc3DEeHmmLAfoZucVR881uASk0Mfjw8xYJ99tb5CcY=
+github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/net v0.0.0-20200202094626-16171245cfb2 h1:CCH4IOTTfewWjGOlSp+zGcjutRKlBEZQ6wTn8ozI/nI=
+golang.org/x/net v0.0.0-20200202094626-16171245cfb2/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
+golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20220715151400-c0bba94af5f8 h1:0A+M6Uqn+Eje4kHMK80dtF3JCXC4ykBgQG4Fe06QRhQ=
+golang.org/x/sys v0.0.0-20220715151400-c0bba94af5f8/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

pkg/cli/BUILD.bazel

@@ -8,5 +8,8 @@ go_library(
     ],
     importpath = "toni.systems/goisoboot/pkg/cli",
     visibility = ["//visibility:public"],
-    deps = ["@com_github_spf13_cobra//:cobra"],
+    deps = [
+        "//pkg/tftp",
+        "@com_github_spf13_cobra//:cobra",
+    ],
 )

pkg/cli/server.go

@@ -1,17 +1,28 @@
 package cli
 
-import "github.com/spf13/cobra"
+import (
+	"fmt"
+	"os"
 
-func server(cmd *cobra.Command, args []string) error {
-	return nil
+	"github.com/spf13/cobra"
+	"toni.systems/goisoboot/pkg/tftp"
+)
+
+func server(cmd *cobra.Command, args []string) {
+	tftp := tftp.New()
+
+	if err := tftp.Run(); err != nil {
+		fmt.Printf("Error: %v\n", err)
+		os.Exit(1)
+	}
 }
 
 func NewServerCmd() *cobra.Command {
 	cmd := &cobra.Command{
 		Use:   "server",
 		Short: "Start the goisoboot server",
 		Long:  "Starts TFTP and HTTP Server",
-		RunE:  server,
+		Run:   server,
 	}
 
 	cmd.Flags().IntP("http-port", "p", 8080, "HTTP Port")

pkg/tftp/BUILD.bazel

@@ -0,0 +1,12 @@
+load("@rules_go//go:def.bzl", "go_library")
+
+go_library(
+    name = "tftp",
+    srcs = ["server.go"],
+    importpath = "toni.systems/goisoboot/pkg/tftp",
+    visibility = ["//visibility:public"],
+    deps = [
+        "@com_github_pin_tftp_v3//:tftp",
+        "@com_github_sirupsen_logrus//:logrus",
+    ],
+)

pkg/tftp/server.go

@@ -0,0 +1,70 @@
+package tftp
+
+import (
+	"errors"
+	"io"
+	"os"
+	"time"
+
+	"github.com/pin/tftp/v3"
+	log "github.com/sirupsen/logrus"
+)
+
+const (
+	ipxeFilename = "ipxe.efi"
+	listenAddr   = ":69"
+)
+
+var (
+	timeout             = 5 * time.Second
+	ErrInvalidFilename  = errors.New("invalid filename, expected ipxe.efi")
+	ErrFailedToOpenFile = errors.New("failed to open file")
+	ErrFailedToReadFile = errors.New("failed to read file")
+)
+
+type Server interface {
+	Run() error
+}
+
+type server struct {
+	tftp     *tftp.Server
+	filename string
+}
+
+func New() Server {
+	s := &server{
+		filename: "./ipxe/ipxe.efi",
+	}
+
+	t := tftp.NewServer(s.ReadHandler, nil)
+	t.SetTimeout(timeout)
+	s.tftp = t
+
+	return s
+}
+
+func (s *server) Run() error {
+	log.Infof("Starting TFTP server on %s", listenAddr)
+	return s.tftp.ListenAndServe(listenAddr) // blocks until s.Shutdown() is called
+}
+
+func (s *server) ReadHandler(filename string, rf io.ReaderFrom) error {
+	log.Infof("Getting file %s", filename)
+	if filename != ipxeFilename {
+		log.Warnf("Filename %s not allowed", filename)
+		return ErrInvalidFilename
+	}
+
+	file, err := os.Open(s.filename)
+	if err != nil {
+		return errors.Join(err, ErrFailedToOpenFile)
+	}
+
+	n, err := rf.ReadFrom(file)
+	if err != nil {
+		return errors.Join(err, ErrFailedToReadFile)
+	}
+
+	log.Infof("File %s %d bytes sent\n", filename, n)
+	return nil
+}