RC-1.0

main.go

@@ -0,0 +1,732 @@
+package main
+
+import (
+	"bytes"
+	"crypto/rand"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"html/template"
+	"io"
+	"log"
+	"math"
+	"math/big"
+	"net/http"
+	"os"
+	"regexp"
+	"sort"
+	"strconv"
+	"strings"
+	"time"
+)
+
+var (
+	lower   = "abcdefghijklmnopqrstuvwxyz"
+	upper   = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+	digits  = "0123456789"
+	symbols = "!@#$%^&*()-=+;:,.?" + "|"      // escaped backslash
+	_       = regexp.MustCompile(`[O0Il1|]+`) // reserved for future validation
+)
+
+// ==== Options & ENV parsing ====
+
+type options struct {
+	length     int
+	minLower   int
+	minUpper   int
+	minDigits  int
+	minSymbols int
+	custom     string
+	exclude    string
+	noAmbig    bool
+	noSeq      bool
+	noRepeat   bool
+	unique     bool
+	template   string
+	symbolSet  string
+	count      int
+	jsonOut    bool
+
+	// Virtual Clipboard target
+	clipBase   string // e.g. http://localhost:8080
+	clipRoom   string // e.g. default
+	clipAuthor string // optional author field
+	clipType   string // usually "text"
+	clipToken  string // X-Token value (falls back to CLIPBOARD_TOKEN)
+
+	// legacy/custom sender (kept for compatibility)
+	sendURL     string
+	sendField   string
+	sendHeaders []string
+	sendMethod  string
+	dryRun      bool
+	timeout     time.Duration
+
+	// web ui
+	webEnabled bool
+	webAddr    string
+	webUser    string
+	webPass    string
+}
+
+func getenvInt(key string, def int) int {
+	if v := os.Getenv(key); v != "" {
+		if i, err := strconv.Atoi(v); err == nil {
+			return i
+		}
+	}
+	return def
+}
+
+func getenvBool(key string, def bool) bool {
+	if v := os.Getenv(key); v != "" {
+		s := strings.ToLower(strings.TrimSpace(v))
+		if s == "1" || s == "true" || s == "yes" || s == "on" {
+			return true
+		}
+		if s == "0" || s == "false" || s == "no" || s == "off" {
+			return false
+		}
+	}
+	return def
+}
+
+func getenvStr(key, def string) string {
+	if v := os.Getenv(key); v != "" {
+		return v
+	}
+	return def
+}
+
+func getenvDuration(key string, def time.Duration) time.Duration {
+	if v := os.Getenv(key); v != "" {
+		if d, err := time.ParseDuration(v); err == nil {
+			return d
+		}
+	}
+	return def
+}
+
+func parseEnv() options {
+	var opt options
+	opt.length = getenvInt("PWGEN_LENGTH", 20)
+	opt.minLower = getenvInt("PWGEN_MIN_LOWER", 1)
+	opt.minUpper = getenvInt("PWGEN_MIN_UPPER", 1)
+	opt.minDigits = getenvInt("PWGEN_MIN_DIGITS", 1)
+	opt.minSymbols = getenvInt("PWGEN_MIN_SYMBOLS", 1)
+	opt.custom = getenvStr("PWGEN_CHARSET", "")
+	opt.exclude = getenvStr("PWGEN_EXCLUDE", "")
+	opt.noAmbig = getenvBool("PWGEN_NO_AMBIGUOUS", true)
+	opt.noSeq = getenvBool("PWGEN_NO_SEQ", true)
+	opt.noRepeat = getenvBool("PWGEN_NO_REPEAT", true)
+	opt.unique = getenvBool("PWGEN_UNIQUE", false)
+	opt.template = getenvStr("PWGEN_TEMPLATE", "")
+	opt.symbolSet = getenvStr("PWGEN_SYMBOLS", symbols)
+	opt.count = getenvInt("PWGEN_COUNT", 1)
+	opt.jsonOut = getenvBool("PWGEN_JSON", false)
+
+	// Virtual Clipboard integration
+	opt.clipBase = getenvStr("PWGEN_CLIPBOARD_BASE", "http://localhost:8080")
+	opt.clipRoom = getenvStr("PWGEN_CLIPBOARD_ROOM", "default")
+	opt.clipAuthor = getenvStr("PWGEN_CLIPBOARD_AUTHOR", "")
+	opt.clipType = getenvStr("PWGEN_CLIPBOARD_TYPE", "text")
+	opt.clipToken = getenvStr("PWGEN_CLIPBOARD_TOKEN", "")
+	if opt.clipToken == "" {
+		opt.clipToken = os.Getenv("CLIPBOARD_TOKEN")
+	}
+
+	// legacy/custom sender (still supported)
+	opt.sendURL = getenvStr("PWGEN_SEND_URL", "")
+	opt.sendField = getenvStr("PWGEN_SEND_FIELD", "content")
+	if h := getenvStr("PWGEN_SEND_HEADERS", ""); h != "" {
+		opt.sendHeaders = strings.Split(h, ";")
+	}
+	opt.sendMethod = getenvStr("PWGEN_SEND_METHOD", "POST")
+	opt.dryRun = getenvBool("PWGEN_DRY_RUN", false)
+	opt.timeout = getenvDuration("PWGEN_TIMEOUT", 10*time.Second)
+
+	opt.webEnabled = getenvBool("PWGEN_WEB", true)
+	// Use a different default port than the VC server to avoid conflicts
+	opt.webAddr = getenvStr("PWGEN_WEB_ADDR", ":8090")
+	opt.webUser = getenvStr("PWGEN_WEB_USER", "")
+	opt.webPass = getenvStr("PWGEN_WEB_PASS", "")
+	return opt
+}
+
+// ==== Core generation logic ====
+
+// randInt returns a crypto-strong uniform integer in [0, n)
+func randInt(n int64) (int64, error) {
+	if n <= 0 {
+		return 0, errors.New("invalid n")
+	}
+	max := big.NewInt(n)
+	x, err := rand.Int(rand.Reader, max)
+	if err != nil {
+		return 0, err
+	}
+	return x.Int64(), nil
+}
+
+func shuffleBytes(b []byte) error {
+	for i := len(b) - 1; i > 0; i-- {
+		j64, err := randInt(int64(i + 1))
+		if err != nil {
+			return err
+		}
+		j := int(j64)
+		b[i], b[j] = b[j], b[i]
+	}
+	return nil
+}
+
+func containsRun(s string, maxRun int) bool {
+	if maxRun <= 1 { // no runs allowed
+		for i := 1; i < len(s); i++ {
+			if s[i] == s[i-1] {
+				return true
+			}
+		}
+		return false
+	}
+	run := 1
+	for i := 1; i < len(s); i++ {
+		if s[i] == s[i-1] {
+			run++
+			if run > maxRun {
+				return true
+			}
+		} else {
+			run = 1
+		}
+	}
+	return false
+}
+
+func hasSeq(s string, window int) bool {
+	if window <= 1 || len(s) < window {
+		return false
+	}
+	for i := 0; i <= len(s)-window; i++ {
+		asc := true
+		for j := 1; j < window; j++ {
+			if s[i+j] != s[i+j-1]+1 {
+				asc = false
+				break
+			}
+		}
+		if asc {
+			return true
+		}
+	}
+	return false
+}
+
+func removeChars(set, exclude string) string {
+	m := make(map[rune]bool)
+	for _, r := range exclude {
+		m[r] = true
+	}
+	var out strings.Builder
+	for _, r := range set {
+		if !m[r] {
+			out.WriteRune(r)
+		}
+	}
+	return out.String()
+}
+
+func buildSets(opt options) (lowerSet, upperSet, digitSet, symbolSet, anySet string) {
+	ls, us, ds, ss := lower, upper, digits, opt.symbolSet
+	if opt.noAmbig {
+		ls = removeChars(ls, "l")
+		us = removeChars(us, "OI")
+		ds = removeChars(ds, "01")
+		ss = removeChars(ss, "|")
+	}
+	if opt.exclude != "" {
+		ls = removeChars(ls, opt.exclude)
+		us = removeChars(us, opt.exclude)
+		ds = removeChars(ds, opt.exclude)
+		ss = removeChars(ss, opt.exclude)
+	}
+	any := uniqueConcat(ls + us + ds + ss + opt.custom)
+	return ls, us, ds, ss, any
+}
+
+func uniqueConcat(s string) string {
+	m := map[rune]bool{}
+	var b strings.Builder
+	for _, r := range s {
+		if !m[r] {
+			m[r] = true
+			b.WriteRune(r)
+		}
+	}
+	return b.String()
+}
+
+func pickRandom(set string) (byte, error) {
+	if len(set) == 0 {
+		return 0, errors.New("empty character set after exclusions")
+	}
+	i, err := randInt(int64(len(set)))
+	if err != nil {
+		return 0, err
+	}
+	return set[i], nil
+}
+
+func generateOne(opt options, sets [5]string) (string, error) {
+	ls, us, ds, ss, anyPool := sets[0], sets[1], sets[2], sets[3], sets[4]
+	if opt.template != "" {
+		return generateFromTemplate(opt, ls, us, ds, ss)
+	}
+	if opt.length <= 0 {
+		return "", errors.New("length must be > 0")
+	}
+	if opt.minLower+opt.minUpper+opt.minDigits+opt.minSymbols > opt.length {
+		return "", errors.New("sum of minimums exceeds length")
+	}
+	bytesBuf := make([]byte, 0, opt.length)
+	for i := 0; i < opt.minLower; i++ {
+		c, err := pickRandom(ls)
+		if err != nil {
+			return "", err
+		}
+		bytesBuf = append(bytesBuf, c)
+	}
+	for i := 0; i < opt.minUpper; i++ {
+		c, err := pickRandom(us)
+		if err != nil {
+			return "", err
+		}
+		bytesBuf = append(bytesBuf, c)
+	}
+	for i := 0; i < opt.minDigits; i++ {
+		c, err := pickRandom(ds)
+		if err != nil {
+			return "", err
+		}
+		bytesBuf = append(bytesBuf, c)
+	}
+	for i := 0; i < opt.minSymbols; i++ {
+		c, err := pickRandom(ss)
+		if err != nil {
+			return "", err
+		}
+		bytesBuf = append(bytesBuf, c)
+	}
+	pool := anyPool
+	if opt.unique && len(pool) < opt.length {
+		return "", fmt.Errorf("unique requested but pool size %d < length %d", len(pool), opt.length)
+	}
+	for len(bytesBuf) < opt.length {
+		c, err := pickRandom(pool)
+		if err != nil {
+			return "", err
+		}
+		if opt.unique && bytesContains(bytesBuf, c) {
+			continue
+		}
+		bytesBuf = append(bytesBuf, c)
+	}
+	if err := shuffleBytes(bytesBuf); err != nil {
+		return "", err
+	}
+	pwd := string(bytesBuf)
+	if opt.noRepeat && containsRun(pwd, 1) {
+		return generateOne(opt, sets)
+	}
+	if opt.noSeq && hasSeq(pwd, 3) {
+		return generateOne(opt, sets)
+	}
+	return pwd, nil
+}
+
+func generateFromTemplate(opt options, ls, us, ds, ss string) (string, error) {
+	var out strings.Builder
+	for i := 0; i < len(opt.template); i++ {
+		ch := opt.template[i]
+		var set string
+		switch ch {
+		case 'l':
+			set = ls
+		case 'L':
+			set = us
+		case 'd':
+			set = ds
+		case 's':
+			set = ss
+		case 'a':
+			set = uniqueConcat(ls + us + ds)
+		case 'A':
+			set = uniqueConcat(ls + us + ds + ss)
+		default:
+			out.WriteByte(ch)
+			continue
+		}
+		c, err := pickRandom(set)
+		if err != nil {
+			return "", err
+		}
+		out.WriteByte(c)
+	}
+	pwd := out.String()
+	if opt.noRepeat && containsRun(pwd, 1) {
+		return generateFromTemplate(opt, ls, us, ds, ss)
+	}
+	if opt.noSeq && hasSeq(pwd, 3) {
+		return generateFromTemplate(opt, ls, us, ds, ss)
+	}
+	return pwd, nil
+}
+
+func bytesContains(b []byte, c byte) bool {
+	for _, x := range b {
+		if x == c {
+			return true
+		}
+	}
+	return false
+}
+
+// entropy helpers
+func entropyForTemplate(tpl string, ls, us, ds, ss string) float64 {
+	bits := 0.0
+	for i := 0; i < len(tpl); i++ {
+		ch := tpl[i]
+		size := 1
+		switch ch {
+		case 'l':
+			size = len(ls)
+		case 'L':
+			size = len(us)
+		case 'd':
+			size = len(ds)
+		case 's':
+			size = len(ss)
+		case 'a':
+			size = len(ls) + len(us) + len(ds)
+		case 'A':
+			size = len(ls) + len(us) + len(ds) + len(ss)
+		default:
+			size = 1
+		}
+		bits += math.Log2(float64(size))
+	}
+	return bits
+}
+
+func entropyForCombined(length int, poolSize int) float64 {
+	return float64(length) * math.Log2(float64(poolSize))
+}
+
+// sendToClipboard posts to Virtual Clipboard (preferred) or legacy custom endpoint
+func sendToClipboard(opt options, pwd string) (bool, error) {
+	// Preferred: Virtual Clipboard
+	if opt.clipBase != "" && opt.clipRoom != "" {
+		url := strings.TrimRight(opt.clipBase, "/") + "/api/" + opt.clipRoom + "/clip"
+		payload := map[string]string{
+			"type":    opt.clipType,
+			"content": pwd,
+		}
+		if opt.clipAuthor != "" {
+			payload["author"] = opt.clipAuthor
+		}
+		body, _ := json.Marshal(payload)
+		if opt.dryRun {
+			log.Printf("[dry-run] VC POST %s -> %s", url, string(body))
+			return false, nil
+		}
+		client := &http.Client{Timeout: opt.timeout}
+		req, err := http.NewRequest(http.MethodPost, url, bytes.NewReader(body))
+		if err != nil {
+			return false, err
+		}
+		req.Header.Set("Content-Type", "application/json")
+		if tok := opt.clipToken; tok != "" {
+			req.Header.Set("X-Token", tok)
+		}
+		resp, err := client.Do(req)
+		if err != nil {
+			return false, err
+		}
+		defer resp.Body.Close()
+		io.ReadAll(resp.Body)
+		if resp.StatusCode >= 200 && resp.StatusCode < 300 {
+			return true, nil
+		}
+		return false, fmt.Errorf("clipboard API responded %s", resp.Status)
+	}
+
+	// Fallback: legacy/custom
+	if opt.sendURL == "" {
+		return false, nil
+	}
+	method := strings.ToUpper(opt.sendMethod)
+	if method == "" {
+		method = "POST"
+	}
+	payload := map[string]string{opt.sendField: pwd}
+	body, _ := json.Marshal(payload)
+	if opt.dryRun {
+		log.Printf("[dry-run] Custom %s %s -> %s (headers=%v)", method, opt.sendURL, string(body), opt.sendHeaders)
+		return false, nil
+	}
+	client := &http.Client{Timeout: opt.timeout}
+	req, err := http.NewRequest(method, opt.sendURL, bytes.NewReader(body))
+	if err != nil {
+		return false, err
+	}
+	req.Header.Set("Content-Type", "application/json")
+	for _, kv := range opt.sendHeaders {
+		parts := strings.SplitN(kv, ":", 2)
+		if len(parts) == 2 {
+			req.Header.Set(strings.TrimSpace(parts[0]), strings.TrimSpace(parts[1]))
+		}
+	}
+	resp, err := client.Do(req)
+	if err != nil {
+		return false, err
+	}
+	defer resp.Body.Close()
+	io.ReadAll(resp.Body)
+	if resp.StatusCode >= 200 && resp.StatusCode < 300 {
+		return true, nil
+	}
+	return false, fmt.Errorf("clipboard API responded %s", resp.Status)
+}
+
+// ==== Web UI ====
+
+var page = template.Must(template.New("idx").Parse(`<!doctype html>
+<html lang="de">
+<head>
+<meta charset="utf-8" />
+<meta name="viewport" content="width=device-width, initial-scale=1" />
+<title>Passwort-Generator</title>
+<style>
+	:root { font-family: system-ui, -apple-system, Segoe UI, Roboto, Ubuntu, Cantarell, Noto Sans, sans-serif; }
+	.container { max-width: 720px; margin: 5vh auto; padding: 24px; border-radius: 16px; box-shadow: 0 8px 30px rgba(0,0,0,.08); }
+	.h1 { font-size: 1.5rem; margin-bottom: 8px; }
+	.sub { color: #555; margin-bottom: 16px; }
+	.btn { display: inline-flex; align-items:center; gap:10px; padding: 12px 16px; border:0; border-radius: 12px; cursor:pointer; font-weight: 600; }
+	.btn-primary { background: #111; color:#fff; }
+	.row { display:flex; gap:12px; align-items:center; }
+	.out { font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace; padding: 10px 12px; border:1px solid #e3e3e3; border-radius: 10px; flex:1; overflow:auto; white-space:pre-wrap; }
+	.badge { display:inline-block; padding:.25rem .5rem; border-radius:999px; background:#f2f2f2; }
+	.footer { margin-top:16px; color:#666; font-size:.9rem; }
+	label { font-size:.9rem; color:#444; }
+</style>
+</head>
+<body>
+	<div class="container">
+		<div class="h1">🔐 Passwort-Generator</div>
+		<div class="sub">Ein Klick – generieren & an den <em>Virtual Clipboard</em>-Server posten.</div>
+		<div class="row" style="margin-bottom:12px;">
+			<label>Count <input id="count" type="number" min="1" max="20" value="1" style="width:90px; padding:8px; border-radius:10px; border:1px solid #e3e3e3" /></label>
+			<button id="go" class="btn btn-primary">Passwort generieren</button>
+			<button id="copy" class="btn" title="in die lokale Browser-Zwischenablage kopieren">Kopieren</button>
+		</div>
+		<div class="out" id="out" placeholder="Hier erscheint das Passwort…"></div>
+		<div style="margin-top:8px; display:flex; gap:10px; align-items:center; flex-wrap:wrap;">
+			<span class="badge" id="entropy">Entropy: –</span>
+			<span class="badge" id="sent">API: –</span>
+			<span class="badge" id="room">Room: {{.Room}}</span>
+			<span class="badge" id="base">Base: {{.Base}}</span>
+		</div>
+		<div class="footer">Server POST: <code>{{.Base}}/api/{{.Room}}/clip</code> · Steuerung per <code>PWGEN_*</code>-ENV.</div>
+	</div>
+<script>
+async function gen(count){
+	const res = await fetch('/api/generate?count='+encodeURIComponent(count||1), {method:'POST', headers:{'X-Requested-With':'fetch'}});
+	if(!res.ok){ const t = await res.text(); throw new Error('HTTP '+res.status+' '+t); }
+	return res.json();
+}
+const go = document.getElementById('go');
+const out = document.getElementById('out');
+const ent = document.getElementById('entropy');
+const sent = document.getElementById('sent');
+const cnt = document.getElementById('count');
+const copy = document.getElementById('copy');
+
+go.addEventListener('click', async ()=>{
+	go.disabled = true; go.textContent='…';
+	try{
+		const data = await gen(cnt.value);
+		if(Array.isArray(data) && data.length){
+			out.textContent = data.map(r=>r.password).join('\n');
+			const median = [...data.map(r=>r.entropy_bits)].sort((a,b)=>a-b)[Math.floor(data.length/2)];
+			ent.textContent = 'Entropy: '+median.toFixed(1)+' bits';
+			sent.textContent = 'API: '+(data.some(r=>r.sent)?'gesendet':'nicht gesendet');
+		}
+	}catch(e){ out.textContent = 'Fehler: '+e.message; }
+	finally{ go.disabled=false; go.textContent='Passwort generieren'; }
+});
+
+copy.addEventListener('click', async ()=>{
+	try{ await navigator.clipboard.writeText(out.textContent); sent.textContent='API: lokal kopiert'; }catch(e){ alert('Kopieren fehlgeschlagen: '+e.message); }
+});
+</script>
+</body>
+</html>`))
+
+func basicAuth(user, pass string, next http.Handler) http.Handler {
+	if user == "" && pass == "" {
+		return next
+	}
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		u, p, ok := r.BasicAuth()
+		if !ok || u != user || p != pass {
+			w.Header().Set("WWW-Authenticate", "Basic realm=restricted")
+			w.WriteHeader(http.StatusUnauthorized)
+			_, _ = w.Write([]byte("Unauthorized"))
+			return
+		}
+		next.ServeHTTP(w, r)
+	})
+}
+
+func withSecurityHeaders(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("X-Content-Type-Options", "nosniff")
+		w.Header().Set("X-Frame-Options", "DENY")
+		w.Header().Set("Referrer-Policy", "no-referrer")
+		w.Header().Set("Cache-Control", "no-store")
+		w.Header().Set("Content-Security-Policy", "default-src 'self'; style-src 'self' 'unsafe-inline'; script-src 'self' 'unsafe-inline'; base-uri 'none'; frame-ancestors 'none'")
+		next.ServeHTTP(w, r)
+	})
+}
+
+func startWeb(opt options) error {
+	ls, us, ds, ss, anyPool := buildSets(opt)
+	sets := [5]string{ls, us, ds, ss, anyPool}
+
+	mux := http.NewServeMux()
+	mux.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "text/html; charset=utf-8")
+		_ = page.Execute(w, map[string]string{"Room": opt.clipRoom, "Base": opt.clipBase})
+	})
+	mux.HandleFunc("/api/generate", func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != http.MethodPost {
+			w.WriteHeader(http.StatusMethodNotAllowed)
+			return
+		}
+		count := 1
+		if c := r.URL.Query().Get("count"); c != "" {
+			if n, err := strconv.Atoi(c); err == nil && n > 0 && n <= 50 {
+				count = n
+			}
+		}
+		res := make([]map[string]interface{}, 0, count)
+		for i := 0; i < count; i++ {
+			pwd, err := generateOne(opt, sets)
+			if err != nil {
+				w.WriteHeader(http.StatusBadRequest)
+				_, _ = w.Write([]byte(err.Error()))
+				return
+			}
+			var bits float64
+			if opt.template != "" {
+				bits = entropyForTemplate(opt.template, ls, us, ds, ss)
+			} else {
+				bits = entropyForCombined(len(pwd), len(anyPool))
+			}
+			sent, err := sendToClipboard(opt, pwd)
+			if err != nil {
+				log.Printf("send error: %v", err)
+			}
+			res = append(res, map[string]interface{}{
+				"password":     pwd,
+				"entropy_bits": bits,
+				"sent":         sent,
+				"send_to":      strings.TrimRight(opt.clipBase, "/") + "/api/" + opt.clipRoom + "/clip",
+			})
+		}
+		w.Header().Set("Content-Type", "application/json")
+		json.NewEncoder(w).Encode(res)
+	})
+
+	h := withSecurityHeaders(basicAuth(opt.webUser, opt.webPass, mux))
+	log.Printf("Web UI listening on %s", opt.webAddr)
+	return http.ListenAndServe(opt.webAddr, h)
+}
+
+// ==== CLI ====
+
+type result struct {
+	Password string  `json:"password"`
+	Entropy  float64 `json:"entropy_bits"`
+	Sent     bool    `json:"sent"`
+	SendTo   string  `json:"send_to,omitempty"`
+}
+
+func runCLI(opt options) int {
+	ls, us, ds, ss, anyPool := buildSets(opt)
+	sets := [5]string{ls, us, ds, ss, anyPool}
+	results := make([]result, 0, opt.count)
+
+	// Resolve effective target URL for reporting
+	sendTo := ""
+	if opt.clipBase != "" && opt.clipRoom != "" {
+		sendTo = strings.TrimRight(opt.clipBase, "/") + "/api/" + opt.clipRoom + "/clip"
+	} else if opt.sendURL != "" {
+		sendTo = opt.sendURL
+	}
+
+	for i := 0; i < opt.count; i++ {
+		pwd, err := generateOne(opt, sets)
+		if err != nil {
+			fmt.Fprintln(os.Stderr, "error:", err)
+			return 1
+		}
+		var bits float64
+		if opt.template != "" {
+			bits = entropyForTemplate(opt.template, ls, us, ds, ss)
+		} else {
+			bits = entropyForCombined(len(pwd), len(anyPool))
+		}
+		sent, err := sendToClipboard(opt, pwd)
+		if err != nil {
+			fmt.Fprintln(os.Stderr, "send error:", err)
+		}
+		results = append(results, result{Password: pwd, Entropy: bits, Sent: sent, SendTo: sendTo})
+	}
+
+	if opt.jsonOut {
+		enc := json.NewEncoder(os.Stdout)
+		enc.SetIndent("", "  ")
+		_ = enc.Encode(results)
+		return 0
+	}
+
+	if opt.count == 1 {
+		fmt.Println(results[0].Password)
+		fmt.Fprintf(os.Stderr, "entropy≈%.1f bits\n", results[0].Entropy)
+	} else {
+		for idx, r := range results {
+			fmt.Printf("%2d: %s\n", idx+1, r.Password)
+		}
+		vals := make([]float64, 0, len(results))
+		for _, r := range results {
+			vals = append(vals, r.Entropy)
+		}
+		sort.Float64s(vals)
+		fmt.Fprintf(os.Stderr, "entropy median≈%.1f bits\n", vals[len(vals)/2])
+	}
+	return 0
+}
+
+// ==== main ====
+
+func main() {
+	opt := parseEnv()
+	if opt.webEnabled {
+		if err := startWeb(opt); err != nil {
+			log.Fatal(err)
+		}
+		return
+	}
+	os.Exit(runCLI(opt))
+}