>1 account

README.md

@@ -5,9 +5,23 @@ Upon successful login, the browser gets a cookie,
 and further attempts to access will get the success page.
 
 I made this to use with the Traefik forward-auth middleware.
+I now use Caddy: it works with that too.
 All I need is a simple password, that's easy to fill with a password manager.
 This checks those boxes.
 
+
+## Format of the `passwd` file
+
+It's just like `/etc/shadow`.
+
+    username:crypted-password
+
+We use sha256,
+until there's a Go library that supports everything.
+
+There's a program included called `crypt` that will output lines for this file.
+
+
 ## Installation with Traefik
 
 You need to have traefik forward the Path `/` to this application.

cmd/crypt/main.go

@@ -0,0 +1,24 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"os"
+
+	"github.com/GehirnInc/crypt"
+	_ "github.com/GehirnInc/crypt/sha256_crypt"
+)
+
+func main() {
+	if len(os.Args) != 3 {
+		log.Fatal("Usage: crypt USERNAME PASSWORD")
+	}
+	username := os.Args[1]
+	password := os.Args[2]
+	c := crypt.SHA256.New()
+	if crypted, err := c.Generate([]byte(password), nil); err != nil {
+		log.Fatal(err)
+	} else {
+		fmt.Printf("%s:%s\n", username, crypted)
+	}
+}

cmd/simpleauth/main.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"bufio"
 	"flag"
 	"fmt"
 	"io/ioutil"
@@ -11,6 +12,8 @@ import (
 	"strings"
 	"time"
 
+	"github.com/GehirnInc/crypt"
+	_ "github.com/GehirnInc/crypt/sha256_crypt"
 	"github.com/nealey/simpleauth/pkg/token"
 )
 
@@ -18,21 +21,25 @@ const CookieName = "auth"
 
 var secret []byte = make([]byte, 256)
 var lifespan time.Duration
-var password string
+var cryptedPasswords map[string]string
 var loginHtml []byte
 var successHtml []byte
 
+func authenticationValid(username, password string) bool {
+	c := crypt.SHA256.New()
+	fmt.Println("checking", username, password)
+	if crypted, ok := cryptedPasswords[username]; ok {
+		fmt.Println(username, password, crypted)
+		if err := c.Verify(crypted, []byte(password)); err == nil {
+			return true
+		} else {
+			log.Println(err)
+		}
+	}
+	return false
+}
+
 func rootHandler(w http.ResponseWriter, req *http.Request) {
-  mechanism := "unauthenticated"
-	authenticated := false
-	if _, passwd, _ := req.BasicAuth(); passwd == password {
-		authenticated = true
-    mechanism = "HTTP-Basic"
-	}
-	if req.FormValue("passwd") == password {
-		authenticated = true
-    mechanism = "Form"
-	}
 	if cookie, err := req.Cookie(CookieName); err == nil {
 		t, _ := token.ParseString(cookie.Value)
 		if t.Valid(secret) {
@@ -43,14 +50,29 @@ func rootHandler(w http.ResponseWriter, req *http.Request) {
 		}
 	}
 
+	authenticated := ""
+
+	if username, password, ok := req.BasicAuth(); ok {
+		if authenticationValid(username, password) {
+			authenticated = "HTTP-Basic"
+		}
+	}
+
+	if authenticationValid(req.FormValue("username"), req.FormValue("password")) {
+		authenticated = "Form"
+	}
+
 	// Log the request
 	clientIP := req.Header.Get("X-Real-IP")
 	if clientIP == "" {
 		clientIP = req.RemoteAddr
 	}
-  log.Printf("%s %s %s [%s]", clientIP, req.Method, req.URL, mechanism)
+	log.Printf("%s %s %s [%s]", clientIP, req.Method, req.URL, authenticated)
 
-	if authenticated {
+	if authenticated == "" {
+		w.WriteHeader(http.StatusUnauthorized)
+		w.Write(loginHtml)
+	} else {
 		t := token.New(secret, time.Now().Add(lifespan))
 		http.SetCookie(w, &http.Cookie{
 			Name:     CookieName,
@@ -59,10 +81,8 @@ func rootHandler(w http.ResponseWriter, req *http.Request) {
 			Secure:   true,
 			SameSite: http.SameSiteStrictMode,
 		})
+		w.WriteHeader(http.StatusOK)
 		w.Write(successHtml)
-	} else {
-		w.WriteHeader(http.StatusUnauthorized)
-		w.Write(loginHtml)
 	}
 }
 
@@ -80,8 +100,8 @@ func main() {
 	)
 	passwordPath := flag.String(
 		"passwd",
-		"/run/secrets/password",
+		"/run/secrets/passwd",
-		"Path to a file containing the password",
+		"Path to a file containing passwords",
 	)
 	secretPath := flag.String(
 		"secret",
@@ -95,11 +115,25 @@ func main() {
 	)
 	flag.Parse()
 
-	passwordBytes, err := ioutil.ReadFile(*passwordPath)
+	cryptedPasswords = make(map[string]string, 10)
-	if err != nil {
+	if f, err := os.Open(*passwordPath); err != nil {
 		log.Fatal(err)
+	} else {
+		defer f.Close()
+		scanner := bufio.NewScanner(f)
+		for scanner.Scan() {
+			line := scanner.Text()
+			parts := strings.Split(line, ":")
+			if len(parts) >= 2 {
+				username := parts[0]
+				password := parts[1]
+				fmt.Println(username, password)
+				cryptedPasswords[username] = password
 			}
-	password = strings.TrimSpace(string(passwordBytes))
+		}
+	}
+
+	var err error
 
 	loginHtml, err = ioutil.ReadFile(path.Join(*htmlPath, "login.html"))
 	if err != nil {
@@ -117,8 +151,8 @@ func main() {
 	}
 	defer f.Close()
 	l, err := f.Read(secret)
-	if l == 0 {
+	if l < 8 {
-		log.Fatal("Secret file provided 0 bytes. That's not enough bytes!")
+		log.Fatalf("Secret file provided %d bytes. That's not enough bytes!", l)
 	} else if err != nil {
 		log.Fatal(err)
 	}

go.mod

@@ -1,3 +1,5 @@
 module github.com/nealey/simpleauth
 
 go 1.13
+
+require github.com/GehirnInc/crypt v0.0.0-20200316065508-bb7000b8a962

go.sum

@@ -0,0 +1,2 @@
+github.com/GehirnInc/crypt v0.0.0-20200316065508-bb7000b8a962 h1:KeNholpO2xKjgaaSyd+DyQRrsQjhbSeS7qe4nEw8aQw=
+github.com/GehirnInc/crypt v0.0.0-20200316065508-bb7000b8a962/go.mod h1:kC29dT1vFpj7py2OvG1khBdQpo3kInWP+6QipLbdngo=

static/login.html

@@ -46,7 +46,8 @@
   <body>
     <h1>Log In</h1>
     <form action="/" method="post">
-      <div>Password: <input type="password" name="passwd"></div>
+      <div>Username: <input name="username"></div>
+      <div>Password: <input type="password" name="password"></div>
       <div><input type="submit" value="Log In"></div>
     </form>
     <div id="error"></div>

static/success.html

@@ -8,7 +8,7 @@
             html {
                 font-family: sans-serif;
                 color: white;
-                background: seagreen linear-gradient(315, rgba(255,255,255,0.2), transparent); 
+                background: seagreen linear-gradient(315deg, rgba(255,255,255,0.2), transparent); 
                 height: 100%;
             }
             div {