feat: add -dev flag for local HTTP testing

In development mode (-dev):
- HSTS header is omitted (prevents browser caching HTTPS-only requirement)
- CSRF cookie Secure flag is cleared (allows cookies over plain HTTP)
- A warning is logged on startup

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

addy.go

@@ -3,13 +3,13 @@ package main
 import (
 	"bytes"
 	"crypto/hmac"
+	"crypto/rand"
 	"crypto/sha256"
 	"encoding/base32"
 	"encoding/json"
 	"flag"
 	"fmt"
 	"log"
-	"math/rand"
 	"net/http"
 	"os"
 	"strings"
@@ -76,7 +76,7 @@ func addyAliasAPIAuth(r *http.Request) (*string, error) {
 	// Decode header
 	authorization, err := base32.StdEncoding.DecodeString(fields[1])
 	if err != nil {
-		log.Println("Invalid Authorization header: %s", err.Error())
+		log.Printf("Invalid Authorization header: %s", err.Error())
 		return nil, err
 	}
 
@@ -89,6 +89,11 @@ func addyAliasAPIAuth(r *http.Request) (*string, error) {
 }
 
 func addyAliasAPI(w http.ResponseWriter, r *http.Request) {
+	if !aliasLimiter.Allow(remoteIP(r)) {
+		http.Error(w, "Too many requests", http.StatusTooManyRequests)
+		return
+	}
+
 	user, err := addyAliasAPIAuth(r)
 	if err != nil {
 		http.Error(w, err.Error(), http.StatusUnauthorized)
@@ -124,6 +129,23 @@ func addyAliasAPI(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
+	// Validate domain against allowlist
+	if len(allowedAliasDomains) == 0 {
+		http.Error(w, "Alias creation is not configured", http.StatusServiceUnavailable)
+		return
+	}
+	domainAllowed := false
+	for _, d := range allowedAliasDomains {
+		if body.Domain == d {
+			domainAllowed = true
+			break
+		}
+	}
+	if !domainAllowed {
+		http.Error(w, "Domain not allowed", http.StatusBadRequest)
+		return
+	}
+
 	if len(body.Alias) == 0 {
 		body.Alias = generateRandomString(10)
 	}
@@ -162,6 +184,11 @@ func addyAliasAPI(w http.ResponseWriter, r *http.Request) {
 }
 
 func addyAliasAPIDelete(w http.ResponseWriter, r *http.Request) {
+	if !aliasLimiter.Allow(remoteIP(r)) {
+		http.Error(w, "Too many requests", http.StatusTooManyRequests)
+		return
+	}
+
 	user, err := addyAliasAPIAuth(r)
 	if err != nil {
 		http.Error(w, err.Error(), http.StatusUnauthorized)
@@ -203,10 +230,14 @@ func addyAliasAPIDelete(w http.ResponseWriter, r *http.Request) {
 }
 
 func generateRandomString(length int) string {
-	charset := "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
+	const charset = "abcdefghijklmnopqrstuvwxyz0123456789"
 	result := make([]byte, length)
-	for i := range result {
-		result[i] = charset[rand.Intn(len(charset))]
+	buf := make([]byte, length)
+	if _, err := rand.Read(buf); err != nil {
+		panic("crypto/rand unavailable: " + err.Error())
+	}
+	for i, b := range buf {
+		result[i] = charset[int(b)%len(charset)]
 	}
 	return string(result)
 }

altcha.go

@@ -0,0 +1,27 @@
+package main
+
+import (
+	"net/http"
+
+	goaltcha "github.com/k42-software/go-altcha"
+	altchahttp "github.com/k42-software/go-altcha/http"
+)
+
+func serveAltchaJS(w http.ResponseWriter, r *http.Request) {
+	altchahttp.ServeJavascript(w, r)
+}
+
+func serveAltchaChallenge(w http.ResponseWriter, r *http.Request) {
+	challenge := goaltcha.NewChallenge()
+	w.Header().Set("Content-Type", "application/json")
+	w.Header().Set("Cache-Control", "private, no-cache, no-store, must-revalidate")
+	_, _ = w.Write([]byte(challenge.Encode()))
+}
+
+func validateAltcha(r *http.Request) bool {
+	encoded := r.PostFormValue("altcha")
+	if encoded == "" {
+		return false
+	}
+	return goaltcha.ValidateResponse(encoded, true)
+}

change.go

@@ -4,46 +4,90 @@ import (
 	"errors"
 	"log"
 	"net/http"
+	"unicode"
 )
 
 func checkPasswdConstraint(password string) error {
-	if len(password) < 8 {
-		return errors.New("too short, please choose a password at least 8 characters long.")
+	if len(password) < 12 {
+		return errors.New("too short, please choose a password at least 12 characters long")
+	}
+
+	var hasUpper, hasLower, hasDigit bool
+	for _, r := range password {
+		switch {
+		case unicode.IsUpper(r):
+			hasUpper = true
+		case unicode.IsLower(r):
+			hasLower = true
+		case unicode.IsDigit(r):
+			hasDigit = true
+		}
+	}
+	if !hasUpper || !hasLower || !hasDigit {
+		return errors.New("password must contain at least one uppercase letter, one lowercase letter, and one digit")
 	}
 
 	return nil
 }
 
 func changePassword(w http.ResponseWriter, r *http.Request) {
-	if r.Method != "POST" {
-		displayTmpl(w, "change.html", map[string]interface{}{})
+	if r.Method == "POST" && !changeLimiter.Allow(remoteIP(r)) {
+		csrfToken, _ := setCSRFToken(w)
+		displayTmplError(w, http.StatusTooManyRequests, "change.html", map[string]interface{}{"error": "Too many requests. Please try again later.", "csrf_token": csrfToken})
 		return
 	}
 
+	if r.Method != "POST" {
+		csrfToken, err := setCSRFToken(w)
+		if err != nil {
+			http.Error(w, "Internal server error", http.StatusInternalServerError)
+			return
+		}
+		displayTmpl(w, "change.html", map[string]interface{}{"csrf_token": csrfToken})
+		return
+	}
+
+	if !validateCSRF(r) {
+		csrfToken, _ := setCSRFToken(w)
+		displayTmplError(w, http.StatusForbidden, "change.html", map[string]interface{}{"error": "Invalid or missing CSRF token. Please try again.", "csrf_token": csrfToken})
+		return
+	}
+
+	if !validateAltcha(r) {
+		csrfToken, _ := setCSRFToken(w)
+		displayTmplError(w, http.StatusForbidden, "change.html", map[string]interface{}{"error": "Invalid or missing altcha response. Please try again.", "csrf_token": csrfToken})
+		return
+	}
+
+	renderError := func(status int, msg string) {
+		csrfToken, _ := setCSRFToken(w)
+		displayTmplError(w, status, "change.html", map[string]interface{}{"error": msg, "csrf_token": csrfToken})
+	}
+
 	// Check the two new passwords are identical
 	if r.PostFormValue("newpassword") != r.PostFormValue("new2password") {
-		displayTmplError(w, http.StatusNotAcceptable, "change.html", map[string]interface{}{"error": "New passwords are not identical. Please retry."})
+		renderError(http.StatusNotAcceptable, "New passwords are not identical. Please retry.")
 	} else if len(r.PostFormValue("login")) == 0 {
-		displayTmplError(w, http.StatusNotAcceptable, "change.html", map[string]interface{}{"error": "Please provide a valid login"})
+		renderError(http.StatusNotAcceptable, "Please provide a valid login")
 	} else if err := checkPasswdConstraint(r.PostFormValue("newpassword")); err != nil {
-		displayTmplError(w, http.StatusNotAcceptable, "change.html", map[string]interface{}{"error": "The password you chose doesn't respect all constraints: " + err.Error()})
+		renderError(http.StatusNotAcceptable, "The password you chose doesn't respect all constraints: "+err.Error())
 	} else {
 		conn, err := myLDAP.Connect()
 		if err != nil || conn == nil {
 			log.Println(err)
-			displayTmplError(w, http.StatusInternalServerError, "change.html", map[string]interface{}{"error": err.Error()})
+			renderError(http.StatusInternalServerError, "Unable to process your request. Please try again later.")
 		} else if err := conn.ServiceBind(); err != nil {
 			log.Println(err)
-			displayTmplError(w, http.StatusInternalServerError, "change.html", map[string]interface{}{"error": err.Error()})
+			renderError(http.StatusInternalServerError, "Unable to process your request. Please try again later.")
 		} else if dn, err := conn.SearchDN(r.PostFormValue("login"), true); err != nil {
 			log.Println(err)
-			displayTmplError(w, http.StatusInternalServerError, "change.html", map[string]interface{}{"error": err.Error()})
+			renderError(http.StatusUnauthorized, "Invalid login or password.")
 		} else if err := conn.Bind(dn, r.PostFormValue("password")); err != nil {
 			log.Println(err)
-			displayTmplError(w, http.StatusUnauthorized, "change.html", map[string]interface{}{"error": err.Error()})
+			renderError(http.StatusUnauthorized, "Invalid login or password.")
 		} else if err := conn.ChangePassword(dn, r.PostFormValue("newpassword")); err != nil {
 			log.Println(err)
-			displayTmplError(w, http.StatusInternalServerError, "change.html", map[string]interface{}{"error": err.Error()})
+			renderError(http.StatusInternalServerError, "Unable to process your request. Please try again later.")
 		} else {
 			displayMsg(w, "Password successfully changed!", http.StatusOK)
 		}

csrf.go

@@ -0,0 +1,40 @@
+package main
+
+import (
+	"crypto/rand"
+	"encoding/base64"
+	"net/http"
+)
+
+func generateCSRFToken() (string, error) {
+	b := make([]byte, 32)
+	if _, err := rand.Read(b); err != nil {
+		return "", err
+	}
+	return base64.URLEncoding.EncodeToString(b), nil
+}
+
+func setCSRFToken(w http.ResponseWriter) (string, error) {
+	token, err := generateCSRFToken()
+	if err != nil {
+		return "", err
+	}
+	http.SetCookie(w, &http.Cookie{
+		Name:     "csrf_token",
+		Value:    token,
+		Path:     "/",
+		HttpOnly: false, // must be readable via form hidden field comparison
+		SameSite: http.SameSiteStrictMode,
+		Secure:   !devMode,
+	})
+	return token, nil
+}
+
+func validateCSRF(r *http.Request) bool {
+	cookie, err := r.Cookie("csrf_token")
+	if err != nil || cookie.Value == "" {
+		return false
+	}
+	formToken := r.PostFormValue("csrf_token")
+	return formToken != "" && cookie.Value == formToken
+}

go.mod

@@ -14,6 +14,8 @@ require (
 	github.com/Azure/go-ntlmssp v0.0.0-20221128193559-754e69321358 // indirect
 	github.com/go-asn1-ber/asn1-ber v1.5.8-0.20250403174932-29230038a667 // indirect
 	github.com/google/uuid v1.6.0 // indirect
+	github.com/k42-software/go-altcha v0.1.1
+	github.com/pkg/errors v0.9.1 // indirect
 	golang.org/x/crypto v0.36.0 // indirect
 	gopkg.in/alexcesaro/quotedprintable.v3 v3.0.0-20150716171945-2caba252f4dc // indirect
 )

go.sum

@@ -41,6 +41,10 @@ github.com/jcmturner/gokrb5/v8 v8.4.4 h1:x1Sv4HaTpepFkXbt2IkL29DXRf8sOfZXo8eRKh6
 github.com/jcmturner/gokrb5/v8 v8.4.4/go.mod h1:1btQEpgT6k+unzCwX1KdWMEwPPkkgBtP+F6aCACiMrs=
 github.com/jcmturner/rpc/v2 v2.0.3 h1:7FXXj8Ti1IaVFpSAziCZWNzbNuZmnvw/i6CqLNdWfZY=
 github.com/jcmturner/rpc/v2 v2.0.3/go.mod h1:VUJYCIDm3PVOEHw8sgt091/20OJjskO/YJki3ELg/Hc=
+github.com/k42-software/go-altcha v0.1.1 h1:vfA+0+0gr7jK4vp21Q7xvEpIjDsx8PqzxS0obgIToQs=
+github.com/k42-software/go-altcha v0.1.1/go.mod h1:2aX+0PkUSI0YPDVfjapZeuGELWt8ugEXkg8gr6QejMU=
+github.com/pkg/errors v0.9.1 h1:FEBLx1zS214owpjy7qsBeixbURkuhQAwrK5UwLGTwt4=
+github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 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/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=

ldap.go

@@ -23,6 +23,7 @@ type LDAP struct {
 	MailPort        int
 	MailUser        string
 	MailPassword    string
+	MailFrom        string
 }
 
 func (l LDAP) Connect() (*LDAPConn, error) {
@@ -74,7 +75,7 @@ func (l LDAPConn) SearchDN(username string, person bool) (string, error) {
 	searchRequest := ldap.NewSearchRequest(
 		l.BaseDN,
 		ldap.ScopeWholeSubtree, ldap.NeverDerefAliases, 0, 0, false,
-		fmt.Sprintf("(&(objectClass=%s)(uid=%s))", objectClass, username),
+		fmt.Sprintf("(&(objectClass=%s)(uid=%s))", ldap.EscapeFilter(objectClass), ldap.EscapeFilter(username)),
 		[]string{"dn"},
 		nil,
 	)
@@ -147,7 +148,7 @@ func (l LDAPConn) SearchMailAlias(address string) (int, error) {
 	searchRequest := ldap.NewSearchRequest(
 		l.BaseDN,
 		ldap.ScopeWholeSubtree, ldap.NeverDerefAliases, 0, 0, false,
-		fmt.Sprintf("(&(objectClass=*)(mailAlias=%s))", address),
+		fmt.Sprintf("(&(objectClass=*)(mailAlias=%s))", ldap.EscapeFilter(address)),
 		[]string{"dn"},
 		nil,
 	)

login.go

@@ -2,9 +2,11 @@ package main
 
 import (
 	"fmt"
+	"html"
 	"html/template"
 	"log"
 	"net/http"
+	"net/url"
 	"strings"
 
 	"github.com/go-ldap/ldap/v3"
@@ -46,6 +48,16 @@ func tryLogin(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
+	if !authLimiter.Allow(remoteIP(r)) {
+		displayTmplError(w, http.StatusTooManyRequests, "login.html", map[string]interface{}{"error": "Too many login attempts. Please try again later."})
+		return
+	}
+
+	if !validateAltcha(r) {
+		displayTmplError(w, http.StatusForbidden, "login.html", map[string]interface{}{"error": "Invalid or missing altcha response. Please try again."})
+		return
+	}
+
 	if entries, err := login(r.PostFormValue("login"), r.PostFormValue("password")); err != nil {
 		log.Println(err)
 		displayTmplError(w, http.StatusInternalServerError, "login.html", map[string]interface{}{"error": err.Error()})
@@ -55,20 +67,34 @@ func tryLogin(w http.ResponseWriter, r *http.Request) {
 		cnt := "<ul>"
 		for _, e := range entries {
 			for i, v := range e.Values {
+				safeName := html.EscapeString(e.Name)
+				safeVal := html.EscapeString(v)
+				elemID := fmt.Sprintf("mailAlias-%d", i)
 				if e.Name == "userPassword" || e.Name == "krbPrincipalKey" {
-					cnt += "<li><strong>" + e.Name + ":</strong> <em>[...]</em></li>"
+					cnt += "<li><strong>" + safeName + ":</strong> <em>[...]</em></li>"
 				} else if e.Name == "mailAlias" && len(strings.SplitN(v, "@", 2)[0]) == 10 {
-					cnt += "<li id='" + fmt.Sprintf("mailAlias-%d", i) + "'><strong>" + e.Name + ":</strong> " + v + `<button type="button" class="mx-1 btn btn-sm btn-danger" onclick="fetch('/api/v1/aliases/` + v + `', {'method': 'delete', 'headers': {'Authorization': 'Bearer ` + apiToken + `'}}).then((res) => { if (res.ok) document.getElementById('` + fmt.Sprintf("mailAlias-%d", i) + `').remove(); });">Supprimer</a></li>`
+					safeURL := url.PathEscape(v)
+					safeToken := html.EscapeString(apiToken)
+					safeElemID := html.EscapeString(elemID)
+					cnt += `<li id="` + safeElemID + `"><strong>` + safeName + `:</strong> ` + safeVal +
+						`<button type="button" class="mx-1 btn btn-sm btn-danger" data-alias="` + safeURL + `" data-token="` + safeToken + `" data-elem="` + safeElemID + `" onclick="(function(b){fetch('/api/v1/aliases/'+b.dataset.alias,{'method':'delete','headers':{'Authorization':'Bearer '+b.dataset.token}}).then(function(r){if(r.ok)document.getElementById(b.dataset.elem).remove();})})(this)">Supprimer</button></li>`
 				} else {
-					cnt += "<li><strong>" + e.Name + ":</strong> " + v + "</li>"
+					cnt += "<li><strong>" + safeName + ":</strong> " + safeVal + "</li>"
 				}
 			}
 		}
-		displayTmpl(w, "message.html", map[string]interface{}{"details": template.HTML(`Login ok<br><br>Here are the information we have about you:` + cnt + "</ul><p>To use our Addy.io compatible API, use the following token: <code>" + apiToken + "</code></p>")})
+		displayTmpl(w, "message.html", map[string]interface{}{"details": template.HTML(`Login ok<br><br>Here are the information we have about you:` + cnt + "</ul><p>To use our Addy.io compatible API, use the following token: <code>" + html.EscapeString(apiToken) + "</code></p>")})
 	}
 }
 
 func httpBasicAuth(w http.ResponseWriter, r *http.Request) {
+	if !authLimiter.Allow(remoteIP(r)) {
+		w.Header().Set("WWW-Authenticate", `Basic realm="nemunai.re restricted"`)
+		w.WriteHeader(http.StatusTooManyRequests)
+		w.Write([]byte("Too many requests"))
+		return
+	}
+
 	if user, pass, ok := r.BasicAuth(); ok {
 		if entries, err := login(user, pass); err != nil {
 			w.Header().Set("WWW-Authenticate", `Basic realm="nemunai.re restricted"`)
@@ -87,7 +113,7 @@ func httpBasicAuth(w http.ResponseWriter, r *http.Request) {
 			}
 			return
 		}
-	} else if v := r.Header.Get("X-Special-Auth"); v == "docker-registry" {
+	} else if dockerRegistrySecret != "" && r.Header.Get("X-Special-Auth") == dockerRegistrySecret {
 		method := r.Header.Get("X-Original-Method")
 		uri := r.Header.Get("X-Original-URI")
 

lost.go

@@ -1,54 +1,64 @@
 package main
 
 import (
-	"crypto/sha512"
+	"crypto/rand"
 	"encoding/base64"
-	"encoding/binary"
 	"io"
 	"log"
 	"net/http"
 	"os"
 	"os/exec"
+	"sync"
 	"time"
 
 	"gopkg.in/gomail.v2"
 )
 
-func (l LDAPConn) genToken(dn string, previous bool) string {
-	hour := time.Now()
-	// Generate the previous token?
-	if previous {
-		hour.Add(time.Hour * -1)
+type resetTokenEntry struct {
+	dn        string
+	expiresAt time.Time
+}
+
+var resetTokenStore = struct {
+	mu     sync.Mutex
+	tokens map[string]resetTokenEntry
+}{tokens: make(map[string]resetTokenEntry)}
+
+func generateResetToken() (string, error) {
+	b := make([]byte, 32)
+	if _, err := rand.Read(b); err != nil {
+		return "", err
 	}
+	return base64.URLEncoding.EncodeToString(b), nil
+}
 
-	b := make([]byte, binary.MaxVarintLen64)
-	binary.PutVarint(b, hour.Round(time.Hour).Unix())
+func storeResetToken(token string, dn string) {
+	resetTokenStore.mu.Lock()
+	defer resetTokenStore.mu.Unlock()
 
-	// Search the email address and current password
-	entries, err := l.GetEntry(dn)
-	if err != nil {
-		log.Println("Unable to generate token:", err)
-		return "#err"
-	}
-
-	email := ""
-	curpasswd := ""
-	for _, e := range entries {
-		if e.Name == "mail" {
-			email += e.Values[0]
-		} else if e.Name == "userPassword" {
-			curpasswd += e.Values[0]
+	// Clean expired tokens
+	now := time.Now()
+	for t, e := range resetTokenStore.tokens {
+		if now.After(e.expiresAt) {
+			delete(resetTokenStore.tokens, t)
 		}
 	}
+	resetTokenStore.tokens[token] = resetTokenEntry{
+		dn:        dn,
+		expiresAt: now.Add(time.Hour),
+	}
+}
 
-	// Hash that
-	hash := sha512.New()
-	hash.Write(b)
-	hash.Write([]byte(dn))
-	hash.Write([]byte(email))
-	hash.Write([]byte(curpasswd))
-
-	return base64.StdEncoding.EncodeToString(hash.Sum(nil)[:])
+func consumeResetToken(token string) (string, bool) {
+	resetTokenStore.mu.Lock()
+	defer resetTokenStore.mu.Unlock()
+	entry, ok := resetTokenStore.tokens[token]
+	if !ok || time.Now().After(entry.expiresAt) {
+		delete(resetTokenStore.tokens, token)
+		return "", false
+	}
+	delete(resetTokenStore.tokens, token)
+	return entry.dn, true
 }
 
 func lostPasswordToken(conn *LDAPConn, login string) (string, string, error) {
@@ -64,15 +74,41 @@ func lostPasswordToken(conn *LDAPConn, login string) (string, string, error) {
 		return "", "", err
 	}
 
-	// Generate the token
-	token := conn.genToken(dn, false)
+	// Generate a cryptographically random token
+	token, err := generateResetToken()
+	if err != nil {
+		return "", "", err
+	}
+
+	// Store token server-side with expiration
+	storeResetToken(token, dn)
 
 	return token, dn, nil
 }
 
 func lostPassword(w http.ResponseWriter, r *http.Request) {
+	if r.Method == "POST" && !lostLimiter.Allow(remoteIP(r)) {
+		displayTmplError(w, http.StatusTooManyRequests, "lost.html", map[string]interface{}{"error": "Too many requests. Please try again later."})
+		return
+	}
+
 	if r.Method != "POST" {
-		displayTmpl(w, "lost.html", map[string]interface{}{})
+		csrfToken, err := setCSRFToken(w)
+		if err != nil {
+			http.Error(w, "Internal server error", http.StatusInternalServerError)
+			return
+		}
+		displayTmpl(w, "lost.html", map[string]interface{}{"csrf_token": csrfToken})
+		return
+	}
+
+	if !validateCSRF(r) {
+		displayTmplError(w, http.StatusForbidden, "lost.html", map[string]interface{}{"error": "Invalid or missing CSRF token. Please try again."})
+		return
+	}
+
+	if !validateAltcha(r) {
+		displayTmplError(w, http.StatusForbidden, "lost.html", map[string]interface{}{"error": "Invalid or missing altcha response. Please try again."})
 		return
 	}
 
@@ -80,7 +116,7 @@ func lostPassword(w http.ResponseWriter, r *http.Request) {
 	conn, err := myLDAP.Connect()
 	if err != nil || conn == nil {
 		log.Println(err)
-		displayTmplError(w, http.StatusInternalServerError, "lost.html", map[string]interface{}{"error": err.Error()})
+		displayTmplError(w, http.StatusInternalServerError, "lost.html", map[string]interface{}{"error": "Unable to process your request. Please try again later."})
 		return
 	}
 
@@ -88,7 +124,8 @@ func lostPassword(w http.ResponseWriter, r *http.Request) {
 	token, dn, err := lostPasswordToken(conn, r.PostFormValue("login"))
 	if err != nil {
 		log.Println(err)
-		displayTmplError(w, http.StatusInternalServerError, "lost.html", map[string]interface{}{"error": err.Error()})
+		// Return generic message to avoid user enumeration
+		displayMsg(w, "If an account with that login exists, a password recovery email has been sent.", http.StatusOK)
 		return
 	}
 
@@ -96,7 +133,7 @@ func lostPassword(w http.ResponseWriter, r *http.Request) {
 	entries, err := conn.GetEntry(dn)
 	if err != nil {
 		log.Println(err)
-		displayTmplError(w, http.StatusInternalServerError, "lost.html", map[string]interface{}{"error": err.Error()})
+		displayMsg(w, "If an account with that login exists, a password recovery email has been sent.", http.StatusOK)
 		return
 	}
 
@@ -113,16 +150,16 @@ func lostPassword(w http.ResponseWriter, r *http.Request) {
 
 	if email == "" {
 		log.Println("Unable to find a valid adress for user " + dn)
-		displayTmplError(w, http.StatusBadRequest, "lost.html", map[string]interface{}{"error": "We were unable to find a valid email address associated with your account. Please contact an administrator."})
+		displayMsg(w, "If an account with that login exists, a password recovery email has been sent.", http.StatusOK)
 		return
 	}
 
 	// Send the email
 	m := gomail.NewMessage()
-	m.SetHeader("From", "noreply@nemunai.re")
+	m.SetHeader("From", myLDAP.MailFrom)
 	m.SetHeader("To", email)
 	m.SetHeader("Subject", "SSO nemunai.re: password recovery")
-	m.SetBody("text/plain", "Hello "+cn+"!\n\nSomeone, and we hope it's you, requested to reset your account password. \nIn order to continue, go to:\n"+BASEURL+"/reset?l="+r.PostFormValue("login")+"&t="+token+"\n\nBest regards,\n-- \nnemunai.re SSO")
+	m.SetBody("text/plain", "Hello "+cn+"!\n\nSomeone, and we hope it's you, requested to reset your account password. \nIn order to continue, go to:\n"+myPublicURL+"/reset?l="+r.PostFormValue("login")+"&t="+token+"\n\nThis link expires in 1 hour and can only be used once.\n\nBest regards,\n-- \nnemunai.re SSO")
 
 	var s gomail.Sender
 	if myLDAP.MailHost != "" {
@@ -130,7 +167,7 @@ func lostPassword(w http.ResponseWriter, r *http.Request) {
 		s, err = d.Dial()
 		if err != nil {
 			log.Println("Unable to connect to email server: " + err.Error())
-			displayTmplError(w, http.StatusInternalServerError, "lost.html", map[string]interface{}{"error": "Unable to connect to email server: " + err.Error()})
+			displayTmplError(w, http.StatusInternalServerError, "lost.html", map[string]interface{}{"error": "Unable to send password recovery email. Please try again later."})
 			return
 		}
 	} else {
@@ -165,7 +202,7 @@ func lostPassword(w http.ResponseWriter, r *http.Request) {
 
 	if err := gomail.Send(s, m); err != nil {
 		log.Println("Unable to send email: " + err.Error())
-		displayTmplError(w, http.StatusInternalServerError, "lost.html", map[string]interface{}{"error": "Unable to send email: " + err.Error()})
+		displayTmplError(w, http.StatusInternalServerError, "lost.html", map[string]interface{}{"error": "Unable to send password recovery email. Please try again later."})
 		return
 	}
 

main.go

@@ -17,13 +17,23 @@ import (
 	"syscall"
 )
 
-const BASEURL = "https://ldap.nemunai.re"
+var myPublicURL = "https://ldap.nemunai.re"
+var devMode bool
+
+// dockerRegistrySecret is required for X-Special-Auth anonymous access.
+// If empty, the feature is disabled.
+var dockerRegistrySecret string
+
+// allowedAliasDomains is the allowlist of domains users may create aliases under.
+// If empty, alias creation is disabled.
+var allowedAliasDomains []string
 
 var myLDAP = LDAP{
 	Host:     "localhost",
 	Port:     389,
 	BaseDN:   "dc=example,dc=com",
 	MailPort: 587,
+	MailFrom: "noreply@nemunai.re",
 }
 
 type ResponseWriterPrefix struct {
@@ -70,8 +80,16 @@ func main() {
 	var bind = flag.String("bind", "127.0.0.1:8080", "Bind port/socket")
 	var baseURL = flag.String("baseurl", "/", "URL prepended to each URL")
 	var configfile = flag.String("config", "", "path to the configuration file")
+	var publicURL = flag.String("public-url", myPublicURL, "Public base URL used in password reset emails")
+	var dev = flag.Bool("dev", false, "Development mode: disables HSTS and cookie Secure flag for local HTTP testing")
 	flag.Parse()
 
+	myPublicURL = *publicURL
+	devMode = *dev
+	if devMode {
+		log.Println("WARNING: running in development mode — security features relaxed, do not use in production")
+	}
+
 	// Sanitize options
 	log.Println("Checking paths...")
 	if *baseURL != "/" {
@@ -141,9 +159,31 @@ func main() {
 	if val, ok := os.LookupEnv("SMTP_USER"); ok {
 		myLDAP.MailUser = val
 	}
-	if val, ok := os.LookupEnv("SMTP_PASSWORD"); ok {
+	if val, ok := os.LookupEnv("SMTP_PASSWORD_FILE"); ok {
+		if fd, err := os.Open(val); err != nil {
+			log.Fatal(err)
+		} else if cnt, err := os.ReadFile(val); err != nil {
+			fd.Close()
+			log.Fatal(err)
+		} else {
+			fd.Close()
+			myLDAP.MailPassword = string(cnt)
+		}
+	} else if val, ok := os.LookupEnv("SMTP_PASSWORD"); ok {
 		myLDAP.MailPassword = val
 	}
+	if val, ok := os.LookupEnv("SMTP_FROM"); ok {
+		myLDAP.MailFrom = val
+	}
+	if val, ok := os.LookupEnv("PUBLIC_URL"); ok {
+		myPublicURL = val
+	}
+	if val, ok := os.LookupEnv("DOCKER_REGISTRY_SECRET"); ok {
+		dockerRegistrySecret = val
+	}
+	if val, ok := os.LookupEnv("ALIAS_ALLOWED_DOMAINS"); ok && val != "" {
+		allowedAliasDomains = strings.Split(val, ",")
+	}
 
 	if flag.NArg() > 0 {
 		switch flag.Arg(0) {
@@ -164,7 +204,7 @@ func main() {
 				log.Fatal(err.Error())
 			}
 
-			fmt.Printf("Reset link for %s: %s/reset?l=%s&t=%s", dn, BASEURL, login, token)
+			fmt.Printf("Reset link for %s: %s/reset?l=%s&t=%s", dn, myPublicURL, login, token)
 			return
 		case "serve":
 		case "server":
@@ -179,6 +219,8 @@ func main() {
 	signal.Notify(interrupt, os.Interrupt, syscall.SIGTERM)
 
 	// Register handlers
+	http.HandleFunc(fmt.Sprintf("GET %s/altcha.min.js", *baseURL), serveAltchaJS)
+	http.HandleFunc(fmt.Sprintf("GET %s/altcha-challenge", *baseURL), serveAltchaChallenge)
 	http.HandleFunc(fmt.Sprintf("%s/{$}", *baseURL), changePassword)
 	http.HandleFunc(fmt.Sprintf("POST %s/api/v1/aliases", *baseURL), addyAliasAPI)
 	http.HandleFunc(fmt.Sprintf("DELETE %s/api/v1/aliases/{alias}", *baseURL), addyAliasAPIDelete)
@@ -189,7 +231,8 @@ func main() {
 	http.HandleFunc(fmt.Sprintf("%s/lost", *baseURL), lostPassword)
 
 	srv := &http.Server{
-		Addr: *bind,
+		Addr:    *bind,
+		Handler: securityHeaders(http.DefaultServeMux),
 	}
 
 	// Serve content

ratelimit.go

@@ -0,0 +1,63 @@
+package main
+
+import (
+	"net"
+	"net/http"
+	"sync"
+	"time"
+)
+
+type rateLimiter struct {
+	mu      sync.Mutex
+	counts  map[string][]time.Time
+	limit   int
+	window  time.Duration
+}
+
+func newRateLimiter(limit int, window time.Duration) *rateLimiter {
+	return &rateLimiter{
+		counts: make(map[string][]time.Time),
+		limit:  limit,
+		window: window,
+	}
+}
+
+func (rl *rateLimiter) Allow(key string) bool {
+	rl.mu.Lock()
+	defer rl.mu.Unlock()
+
+	now := time.Now()
+	windowStart := now.Add(-rl.window)
+
+	timestamps := rl.counts[key]
+	filtered := timestamps[:0]
+	for _, t := range timestamps {
+		if t.After(windowStart) {
+			filtered = append(filtered, t)
+		}
+	}
+
+	if len(filtered) >= rl.limit {
+		rl.counts[key] = filtered
+		return false
+	}
+
+	rl.counts[key] = append(filtered, now)
+	return true
+}
+
+var (
+	authLimiter   = newRateLimiter(20, time.Minute)
+	changeLimiter = newRateLimiter(10, time.Minute)
+	lostLimiter   = newRateLimiter(5, time.Minute)
+	resetLimiter  = newRateLimiter(10, time.Minute)
+	aliasLimiter  = newRateLimiter(30, time.Minute)
+)
+
+func remoteIP(r *http.Request) string {
+	host, _, err := net.SplitHostPort(r.RemoteAddr)
+	if err != nil {
+		return r.RemoteAddr
+	}
+	return host
+}

reset.go

@@ -3,32 +3,66 @@ package main
 import (
 	"log"
 	"net/http"
-	"strings"
 )
 
 func resetPassword(w http.ResponseWriter, r *http.Request) {
+	if r.Method == "POST" && !resetLimiter.Allow(remoteIP(r)) {
+		http.Error(w, "Too many requests. Please try again later.", http.StatusTooManyRequests)
+		return
+	}
+
 	if len(r.URL.Query().Get("l")) == 0 || len(r.URL.Query().Get("t")) == 0 {
 		http.Redirect(w, r, "lost", http.StatusFound)
+		return
 	}
 
 	base := map[string]interface{}{
 		"login": r.URL.Query().Get("l"),
-		"token": strings.Replace(r.URL.Query().Get("t"), " ", "+", -1),
+		"token": r.URL.Query().Get("t"),
 	}
 
 	if r.Method != "POST" {
+		csrfToken, err := setCSRFToken(w)
+		if err != nil {
+			http.Error(w, "Internal server error", http.StatusInternalServerError)
+			return
+		}
+		base["csrf_token"] = csrfToken
 		displayTmpl(w, "reset.html", base)
 		return
 	}
 
+	renderError := func(status int, msg string) {
+		csrfToken, _ := setCSRFToken(w)
+		base["error"] = msg
+		base["csrf_token"] = csrfToken
+		displayTmplError(w, status, "reset.html", base)
+	}
+
+	if !validateCSRF(r) {
+		renderError(http.StatusForbidden, "Invalid or missing CSRF token. Please try again.")
+		return
+	}
+
+	if !validateAltcha(r) {
+		renderError(http.StatusForbidden, "Invalid or missing altcha response. Please try again.")
+		return
+	}
+
 	// Check the two new passwords are identical
 	if r.PostFormValue("newpassword") != r.PostFormValue("new2password") {
-		base["error"] = "New passwords are not identical. Please retry."
-		displayTmplError(w, http.StatusNotAcceptable, "reset.html", base)
+		renderError(http.StatusNotAcceptable, "New passwords are not identical. Please retry.")
 		return
 	} else if err := checkPasswdConstraint(r.PostFormValue("newpassword")); err != nil {
-		base["error"] = "The password you chose doesn't respect all constraints: " + err.Error()
-		displayTmplError(w, http.StatusNotAcceptable, "reset.html", base)
+		renderError(http.StatusNotAcceptable, "The password you chose doesn't respect all constraints: "+err.Error())
+		return
+	}
+
+	// Validate and consume the token (single-use, server-side)
+	token := r.PostFormValue("token")
+	dn, ok := consumeResetToken(token)
+	if !ok {
+		renderError(http.StatusNotAcceptable, "Token invalid or expired, please retry the lost password procedure. Tokens expire after 1 hour.")
 		return
 	}
 
@@ -36,41 +70,22 @@ func resetPassword(w http.ResponseWriter, r *http.Request) {
 	conn, err := myLDAP.Connect()
 	if err != nil || conn == nil {
 		log.Println(err)
-		base["error"] = err.Error()
-		displayTmplError(w, http.StatusInternalServerError, "reset.html", base)
+		renderError(http.StatusInternalServerError, "Unable to process your request. Please try again later.")
 		return
 	}
 
-	// Bind as service to perform the search
+	// Bind as service to perform the password change
 	err = conn.ServiceBind()
 	if err != nil {
 		log.Println(err)
-		base["error"] = err.Error()
-		displayTmplError(w, http.StatusInternalServerError, "reset.html", base)
-		return
-	}
-
-	// Search the dn of the given user
-	dn, err := conn.SearchDN(r.PostFormValue("login"), true)
-	if err != nil {
-		log.Println(err)
-		base["error"] = err.Error()
-		displayTmplError(w, http.StatusInternalServerError, "reset.html", base)
-		return
-	}
-
-	// Check token validity (allow current token + last one)
-	if conn.genToken(dn, false) != r.PostFormValue("token") && conn.genToken(dn, true) != r.PostFormValue("token") {
-		base["error"] = "Token invalid, please retry the lost password procedure. Please note that our token expires after 1 hour."
-		displayTmplError(w, http.StatusNotAcceptable, "reset.html", base)
+		renderError(http.StatusInternalServerError, "Unable to process your request. Please try again later.")
 		return
 	}
 
 	// Replace the password by the new given
 	if err := conn.ChangePassword(dn, r.PostFormValue("newpassword")); err != nil {
 		log.Println(err)
-		base["error"] = err.Error()
-		displayTmplError(w, http.StatusInternalServerError, "reset.html", base)
+		renderError(http.StatusInternalServerError, "Unable to process your request. Please try again later.")
 		return
 	}
 

static.go

@@ -7,6 +7,19 @@ import (
 	"net/http"
 )
 
+func securityHeaders(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("X-Frame-Options", "DENY")
+		w.Header().Set("X-Content-Type-Options", "nosniff")
+		w.Header().Set("Referrer-Policy", "strict-origin-when-cross-origin")
+		w.Header().Set("Content-Security-Policy", "default-src 'self'; script-src 'self' 'wasm-unsafe-eval' 'unsafe-inline' https://stackpath.bootstrapcdn.com; style-src https://stackpath.bootstrapcdn.com; img-src 'self'; font-src https://stackpath.bootstrapcdn.com")
+		if !devMode {
+			w.Header().Set("Strict-Transport-Security", "max-age=63072000; includeSubDomains")
+		}
+		next.ServeHTTP(w, r)
+	})
+}
+
 //go:embed all:static
 var assets embed.FS
 

static/change.html

@@ -3,6 +3,7 @@
 
   <form method="post" action="change">
     {{if .error}}<div class="alert alert-danger" role="alert">{{.error}}</div>{{end}}
+    <input type="hidden" name="csrf_token" value="{{ .csrf_token }}">
     <div class="form-group">
       <input name="login" required="" class="form-control" id="input_0" type="text" placeholder="Login" autofocus>
     </div>
@@ -39,6 +40,9 @@
         </button>
       </div>
     </div>
+    <div class="form-group">
+      <altcha-widget challengeurl="altcha-challenge"></altcha-widget>
+    </div>
     <button class="btn btn-primary" type="submit">Change my password</button>
     <a href="/lost" class="btn btn-outline-secondary">Forgot your password?</a>
   </form>

static/header.html

@@ -10,6 +10,7 @@
     <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/css/bootstrap.min.css" integrity="sha384-MCw98/SFnGE8fJT3GXwEOngsV7Zt27NXFoaoApmYm81iuXoPkFOJwJ8ERdknLPMO" crossorigin="anonymous">
 
     <title>nemunai.re password change</title>
+    <script src="altcha.min.js" async defer></script>
   </head>
   <body>
     <div class="container">

static/login.html

@@ -9,6 +9,9 @@
     <div class="form-group">
       <input name="password" required="" class="form-control" id="input_1" type="password" placeholder="Current password">
     </div>
+    <div class="form-group">
+      <altcha-widget challengeurl="altcha-challenge"></altcha-widget>
+    </div>
     <button class="btn btn-primary" type="submit">Sign in</button>
     <a href="/lost" class="btn btn-outline-secondary">Forgot your password?</a>
     </form>

static/lost.html

@@ -3,9 +3,13 @@
 
   <form method="post" action="lost">
     {{if .error}}<div class="alert alert-danger" role="alert">{{.error}}</div>{{end}}
+    <input type="hidden" name="csrf_token" value="{{ .csrf_token }}">
     <div class="form-group">
       <input name="login" required="" class="form-control" id="input_0" type="text" placeholder="Login" autofocus>
     </div>
+    <div class="form-group">
+      <altcha-widget challengeurl="altcha-challenge"></altcha-widget>
+    </div>
     <button class="btn btn-primary" type="submit">Reset my password</button>
     <a href="/change" class="btn btn-outline-success">Just want to change your password?</a>
   </form>

static/reset.html

@@ -1,8 +1,9 @@
 {{template "header"}}
   <h1 class="display-4">Forgot your password? <small class="text-muted">Define a new one!</small></h1>
 
-  <form method="post" action="reset?l={{ .login }}&t={{ .token }}">
+  <form method="post" action="reset">
     {{if .error}}<div class="alert alert-danger" role="alert">{{.error}}</div>{{end}}
+    <input type="hidden" name="csrf_token" value="{{ .csrf_token }}">
     <div class="form-group">
       <input required="" class="form-control" id="input_0" type="text" placeholder="Email" value="{{ .login }}" disabled="">
     </div>
@@ -14,6 +15,9 @@
     <div class="form-group">
       <input name="new2password" required="" class="form-control" id="input_3" type="password" placeholder="Retype new password">
     </div>
+    <div class="form-group">
+      <altcha-widget challengeurl="altcha-challenge"></altcha-widget>
+    </div>
     <button class="btn btn-primary" type="submit">Reset my password</button>
   </form>
 {{template "footer"}}