widdler/main.go
2021-05-17 07:50:45 -06:00

163 lines
3.3 KiB
Go

package main
import (
"embed"
"encoding/csv"
"flag"
"fmt"
"io/ioutil"
"log"
"net"
"net/http"
"os"
"path"
"path/filepath"
"time"
"golang.org/x/crypto/bcrypt"
"golang.org/x/net/webdav"
"suah.dev/protect"
)
var twFile = "empty-5.1.23.html"
//go:embed empty-5.1.23.html
var tiddly embed.FS
var (
test bool
cacheDir string
davDir string
listen string
passPath string
users map[string]string
)
func init() {
users = make(map[string]string)
dir, err := filepath.Abs(filepath.Dir(os.Args[0]))
if err != nil {
log.Fatalln(err)
}
flag.StringVar(&cacheDir, "cache", fmt.Sprintf("%s/.cache", dir), "Directory in which to store ACME certificates.")
flag.StringVar(&davDir, "davdir", dir, "Directory to serve over WebDAV.")
flag.StringVar(&listen, "http", "127.0.0.1:8080", "Listen on")
flag.StringVar(&passPath, "htpass", fmt.Sprintf("%s/.htpasswd", dir), "Path to .htpasswd file..")
flag.BoolVar(&test, "test", false, "Enable testing mode (uses staging LetsEncrypt).")
flag.Parse()
// These are OpenBSD specific protections used to prevent unnecessary file access.
_ = protect.Unveil(passPath, "r")
_ = protect.Unveil(davDir, "rwc")
_ = protect.Unveil(cacheDir, "rwc")
_ = protect.Unveil("/etc/ssl/cert.pem", "r")
_ = protect.Unveil("/etc/resolv.conf", "r")
_ = protect.Pledge("stdio wpath rpath cpath inet dns")
p, err := os.Open(passPath)
if err != nil {
log.Fatal(err)
}
defer p.Close()
ht := csv.NewReader(p)
ht.Comma = ':'
ht.Comment = '#'
ht.TrimLeadingSpace = true
entries, err := ht.ReadAll()
if err != nil {
log.Fatal(err)
}
for _, parts := range entries {
users[parts[0]] = parts[1]
}
}
func authenticate(user string, pass string) bool {
htpass, exists := users[user]
if !exists {
return false
}
err := bcrypt.CompareHashAndPassword([]byte(htpass), []byte(pass))
return err == nil
}
func logger(f http.HandlerFunc) http.HandlerFunc {
return func(w http.ResponseWriter, r *http.Request) {
n := time.Now()
fmt.Printf("%s (%s) [%s] \"%s %s\" %03d\n",
r.RemoteAddr,
n.Format(time.RFC822Z),
r.Method,
r.URL.Path,
r.Proto,
r.ContentLength,
)
f(w, r)
}
}
func createEmpty(path string) error {
_, fErr := os.Stat(path)
if os.IsNotExist(fErr) {
log.Printf("creating %q\n", path)
twData, _ := tiddly.ReadFile(twFile)
wErr := ioutil.WriteFile(path, []byte(twData), 0600)
if wErr != nil {
return wErr
}
}
return nil
}
func main() {
wdav := &webdav.Handler{
LockSystem: webdav.NewMemLS(),
FileSystem: webdav.Dir(davDir),
}
idxHandler := http.FileServer(http.Dir(davDir))
mux := http.NewServeMux()
mux.HandleFunc("/", logger(func(w http.ResponseWriter, r *http.Request) {
user, pass, ok := r.BasicAuth()
if !(ok && authenticate(user, pass)) {
w.Header().Set("WWW-Authenticate", `Basic realm="davfs"`)
http.Error(w, "Unauthorized", http.StatusUnauthorized)
return
}
fp := path.Join(davDir, r.URL.Path)
err := createEmpty(fp)
if err != nil {
log.Println(err)
fmt.Fprintf(w, err.Error())
return
}
if r.URL.Path == "/" {
idxHandler.ServeHTTP(w, r)
return
}
wdav.ServeHTTP(w, r)
}))
s := http.Server{
Handler: mux,
}
lis, err := net.Listen("tcp", listen)
if err != nil {
log.Panic(err)
}
log.Printf("Listening for HTTP on '%s'", listen)
log.Panic(s.Serve(lis))
}