internal/config/config.go

782 lines · 28617 bytes

  1// Package config loads and validates the gitbayd server configuration.
  2package config
  3
  4import (
  5	"crypto/ecdsa"
  6	"crypto/x509"
  7	"encoding/pem"
  8	"errors"
  9	"fmt"
 10	"io"
 11	"math"
 12	"net"
 13	"os"
 14	"path/filepath"
 15	"strconv"
 16	"strings"
 17	"time"
 18
 19	"filippo.io/age"
 20	"github.com/BurntSushi/toml"
 21)
 22
 23// DefaultWriteRate is the per-account write budget when the config leaves
 24// write_rate at zero: generous for a person at a terminal, and a bound on
 25// what one account can enqueue — every write also queues notification mail
 26// and webhook deliveries.
 27const DefaultWriteRate = 60
 28
 29// Pack generation defaults for a four-core host: a full clone of a large
 30// repository runs git at about 1.5 cores (Performance wiki page).
 31const (
 32	DefaultPackConcurrency  = 3
 33	DefaultPackPerPrincipal = 2
 34	DefaultPackQueue        = 32
 35	DefaultPackQueueWait    = time.Minute
 36)
 37
 38type Config struct {
 39	Server       Server       `toml:"server"`
 40	SSH          SSH          `toml:"ssh"`
 41	HTTP         HTTP         `toml:"http"`
 42	GitDaemon    GitDaemon    `toml:"git_daemon"`
 43	Web          Web          `toml:"web"`
 44	Registration Registration `toml:"registration"`
 45	API          API          `toml:"api"`
 46	Webhooks     Webhooks     `toml:"webhooks"`
 47	Pages        Pages        `toml:"pages"`
 48	LFS          LFS          `toml:"lfs"`
 49	Limits       Limits       `toml:"limits"`
 50	Mail         Mail         `toml:"mail"`
 51	Mirrors      Mirrors      `toml:"mirrors"`
 52	Deps         Deps         `toml:"deps"`
 53	Retention    Retention    `toml:"retention"`
 54	Push         Push         `toml:"push"`
 55	Backup       Backup       `toml:"backup"`
 56	// GoImport maps vanity Go module paths to repositories, e.g.
 57	// "gitbay.org/gitbay" = "krz/gitbay". Requests carrying ?go-get=1
 58	// under a mapped path get a go-import meta tag.
 59	GoImport map[string]string `toml:"go_import"`
 60}
 61
 62type Server struct {
 63	Root    string `toml:"root"`
 64	SiteURL string `toml:"site_url"`
 65
 66	// SourceRepo names the repository this instance develops itself in, as
 67	// "owner/name". When set, startup warns if the running build's commit is
 68	// not on that repository's default branch. Empty disables the check, which
 69	// is right for any instance that does not host its own source.
 70	SourceRepo string `toml:"source_repo"`
 71
 72	// SecretKeyFile holds the keys that seal the secret columns of the
 73	// database (internal/seal). It lives outside Root, so neither a
 74	// backup archive nor a snapshot of Root carries it.
 75	SecretKeyFile string `toml:"secret_key_file"`
 76}
 77
 78type SSH struct {
 79	Mode     string   `toml:"mode"` // embedded | system
 80	Port     int      `toml:"port"`
 81	HostKeys []string `toml:"host_keys"`
 82}
 83
 84type HTTP struct {
 85	Addr     string `toml:"addr"`
 86	TLS      string `toml:"tls"` // acme | files | off
 87	CertFile string `toml:"cert_file"`
 88	KeyFile  string `toml:"key_file"`
 89	// ACME (Let's Encrypt by default). Certificates are cached under
 90	// server.root/acme. acme_http_addr serves HTTP-01 challenges and
 91	// redirects to HTTPS; "off" disables it (TLS-ALPN-01 on the HTTPS
 92	// port still works).
 93	ACMEEmail    string `toml:"acme_email"`
 94	ACMEHTTPAddr string `toml:"acme_http_addr"`
 95	// TrustedProxies are the addresses or CIDRs of reverse proxies in front
 96	// of this process. A request from one of them is attributed to the
 97	// last X-Forwarded-For hop that is not itself a trusted proxy; from
 98	// anyone else the peer address is the client and the header is
 99	// ignored. Empty means no proxy, which is how gitbayd is deployed by
100	// default: it terminates TLS itself.
101	TrustedProxies []string `toml:"trusted_proxies,omitempty"`
102}
103
104type GitDaemon struct {
105	Enabled bool `toml:"enabled"`
106	Port    int  `toml:"port"`
107}
108
109type Web struct {
110	Mode         string `toml:"mode"` // view_only | accounts
111	PasswordAuth bool   `toml:"password_auth"`
112	// Title is the instance's display name in the header and page titles.
113	// Empty falls back to the site host.
114	Title string `toml:"title"`
115	// PrivacyNotice is operator-provided text shown on /privacy under the
116	// fixed project-level statement. Plain text; blank paragraphs split.
117	PrivacyNotice string `toml:"privacy_notice"`
118}
119
120type Registration struct {
121	Mode string `toml:"mode"` // closed | invite | open
122	// PendingExpiry is how long a self-registered account may stay
123	// unverified before it is removed, as a duration ("168h"). Empty
124	// keeps such accounts forever.
125	PendingExpiry string `toml:"pending_expiry"`
126	// NotifyAdmin mails the instance's admins when an account becomes
127	// active: an invite redeemed, or an open-mode signup that verified
128	// its address. The unverified row an open signup creates is not
129	// reported — anyone can post the form, so mailing on that would
130	// aim a flood at the admins (#234).
131	NotifyAdmin bool `toml:"notify_admin"`
132}
133
134// PendingExpiryDuration parses PendingExpiry; zero means never.
135func (r Registration) PendingExpiryDuration() time.Duration {
136	d, _ := time.ParseDuration(r.PendingExpiry)
137	return d
138}
139
140// Retention is how long the append-only tables keep a row. Each is a
141// duration string ("2160h"); empty or zero keeps forever, which is what
142// an instance that has never configured this gets. Expired sessions and
143// tokens are swept regardless: they are dead weight the moment they
144// expire and no setting makes them worth keeping.
145type Retention struct {
146	Audit             string `toml:"audit"`
147	Events            string `toml:"events"`
148	WebhookDeliveries string `toml:"webhook_deliveries"`
149	// Mail is the outbound queue: rows already sent or given up on.
150	Mail string `toml:"mail"`
151	// Push is the outbound device queue: rows already sent or given up on.
152	Push string `toml:"push"`
153}
154
155// Durations parses the five, mapping each to zero when unset or bad.
156func (r Retention) Durations() (audit, events, deliveries, mail, push time.Duration) {
157	parse := func(s string) time.Duration {
158		d, err := time.ParseDuration(s)
159		if err != nil || d < 0 {
160			return 0
161		}
162		return d
163	}
164	return parse(r.Audit), parse(r.Events), parse(r.WebhookDeliveries), parse(r.Mail), parse(r.Push)
165}
166
167// LFS stores large-file objects content-addressed under Root (default
168// <server.root>/lfs). MaxObjectBytes caps a single object; 0 means the
169// 512MB default.
170type LFS struct {
171	Root           string `toml:"root"`
172	MaxObjectBytes int64  `toml:"max_object_bytes"`
173}
174
175// Pages serves each public repo's `pages` branch as a static site on
176// <owner>.<domain> — a separate origin, so page-authored scripts never run
177// on the forge's own host. Empty domain disables the feature.
178type Pages struct {
179	Domain string `toml:"domain"`
180}
181
182// API controls the HTTPS/JSON control-plane API (bearer tokens minted over
183// SSH). Off by default: an instance that never enables it has no
184// credential-bearing HTTP surface at all.
185type API struct {
186	Enabled bool `toml:"enabled"`
187}
188
189// Webhooks controls outbound delivery. AllowLocal permits endpoints on
190// loopback/private addresses (off by default: SSRF).
191type Webhooks struct {
192	AllowLocal bool `toml:"allow_local"`
193}
194
195type Mirrors struct {
196	PullIntervalMinutes int `toml:"pull_interval_minutes"`
197}
198
199// Deps configures the dependency-update sweep. It runs only for repos that
200// have opted in with `repo deps enable`, because checking a private repo
201// tells a public registry what it depends on.
202type Deps struct {
203	CheckIntervalHours int `toml:"check_interval_hours"`
204}
205
206type Limits struct {
207	MaxPackBytes    int64 `toml:"max_pack_bytes"`
208	MaxBlobBytes    int64 `toml:"max_blob_bytes"`
209	MaxAssetBytes   int64 `toml:"max_asset_bytes"`   // per release asset
210	MaxSnippetBytes int64 `toml:"max_snippet_bytes"` // per snippet file
211	// MaxSnippetsPerUser caps snippets an account may own. 0 means
212	// unlimited, like MaxReposPerUser.
213	MaxSnippetsPerUser int `toml:"max_snippets_per_user"`
214	CloneTimeoutSec    int `toml:"clone_timeout"`
215	SSHAuthRate        int `toml:"ssh_auth_rate"`
216	// APIRate is sustained JSON-API requests per minute per caller; writes
217	// draw on a tenth of it. 0 uses the default.
218	APIRate int `toml:"api_rate"`
219	// WriteRate is sustained mutating commands per minute per account,
220	// counted in the dispatcher so every surface shares one budget. 0 uses
221	// the default; a negative value turns the limit off.
222	WriteRate int `toml:"write_rate"`
223	// Per-account quotas on what a user owns directly (organizations are
224	// not capped). 0 means unlimited; admin user limits overrides per
225	// account.
226	MaxReposPerUser int   `toml:"max_repos_per_user"`
227	MaxBytesPerUser int64 `toml:"max_bytes_per_user"`
228	// PackConcurrency caps git pack generation (upload-pack and
229	// upload-archive) running at once across SSH, smart HTTP and git://.
230	// PackPerPrincipal caps it per account, or per client address on the
231	// anonymous transports. PackQueue is how many may wait for a slot,
232	// for at most PackQueueWait ("60s"). For the three counts 0 takes the
233	// default and a negative value turns that bound off.
234	PackConcurrency  int    `toml:"pack_concurrency"`
235	PackPerPrincipal int    `toml:"pack_per_principal"`
236	PackQueue        int    `toml:"pack_queue"`
237	PackQueueWait    string `toml:"pack_queue_wait"`
238}
239
240// PackLimits resolves the pack_* settings for packlimit.New. A zero
241// max or per is no bound; an unbounded queue is math.MaxInt, since
242// packlimit reads a zero queue as no queue at all.
243func (l Limits) PackLimits() (max, per, queue int, wait time.Duration) {
244	pick := func(v, def int) int {
245		switch {
246		case v == 0:
247			return def
248		case v < 0:
249			return 0
250		}
251		return v
252	}
253	queue = pick(l.PackQueue, DefaultPackQueue)
254	if l.PackQueue < 0 {
255		queue = math.MaxInt
256	}
257	wait = DefaultPackQueueWait
258	if d, err := time.ParseDuration(l.PackQueueWait); err == nil && d > 0 {
259		wait = d
260	}
261	return pick(l.PackConcurrency, DefaultPackConcurrency),
262		pick(l.PackPerPrincipal, DefaultPackPerPrincipal), queue, wait
263}
264
265type Mail struct {
266	SMTPHost string `toml:"smtp_host"` // host:port (port defaults to 587, 465 with tls = "implicit")
267	From     string `toml:"from"`
268	SMTPUser string `toml:"smtp_user,omitempty"`
269	SMTPPass string `toml:"smtp_pass,omitempty"`
270	// RequireTLS fails delivery when the relay does not offer STARTTLS,
271	// instead of sending in clear. Unset, it is on for any relay but
272	// localhost or a loopback address (TLSRequired).
273	RequireTLS *bool `toml:"require_tls,omitempty"`
274	// TLS is "starttls" (the default, also when empty) or "implicit":
275	// TLS from the first byte, as relays on port 465 expect.
276	TLS string `toml:"tls,omitempty"`
277	// Inbound polls a mailbox for replies to notification mail (#295).
278	Inbound MailInbound `toml:"inbound"`
279}
280
281// MailInbound is the IMAP mailbox replies to notification mail arrive
282// in. Off unless enabled. The connection is always encrypted; there is
283// no setting for plaintext.
284type MailInbound struct {
285	Enabled bool `toml:"enabled"`
286	// IMAPHost is host:port; the port defaults to 993 with tls =
287	// "implicit" (the default) and 143 with tls = "starttls".
288	IMAPHost string `toml:"imap_host"`
289	TLS      string `toml:"tls"`
290	User     string `toml:"user"`
291	// PasswordFile holds the mailbox password, read at each connection.
292	// Never inline in this file.
293	PasswordFile string `toml:"password_file"`
294	Mailbox      string `toml:"mailbox"`       // default INBOX
295	PollInterval string `toml:"poll_interval"` // default 1m
296	// ReplyAddress is the address a notification's Reply-To is built
297	// from: reply@example.org becomes reply+<token>@example.org, so the
298	// mailbox must receive plus-addressed mail for it (or a catch-all).
299	ReplyAddress string `toml:"reply_address"`
300	// TrustedAuthservID is the authserv-id the mail host writes in its
301	// Authentication-Results header. When set, a reply must carry DMARC
302	// pass, or an aligned DKIM pass, in the topmost such header. Only
303	// safe when the mail host removes incoming headers claiming its id.
304	TrustedAuthservID string `toml:"trusted_authserv_id"`
305	// RequireDKIM makes a reply need a DKIM signature, verified by
306	// gitbayd, that covers From and whose d= is in relaxed alignment
307	// with the From domain. With TrustedAuthservID also set, either
308	// passing is enough.
309	RequireDKIM bool `toml:"require_dkim"`
310}
311
312// Authenticated reports whether a reply's From is checked at all.
313func (m MailInbound) Authenticated() bool {
314	return m.TrustedAuthservID != "" || m.RequireDKIM
315}
316
317// DefaultInboundPoll is the poll interval when poll_interval is unset.
318const DefaultInboundPoll = time.Minute
319
320// Poll is the configured poll interval.
321func (m MailInbound) Poll() time.Duration {
322	if d, err := time.ParseDuration(m.PollInterval); err == nil && d > 0 {
323		return d
324	}
325	return DefaultInboundPoll
326}
327
328// Addr is IMAPHost with the default port filled in.
329func (m MailInbound) Addr() string {
330	if _, _, err := net.SplitHostPort(m.IMAPHost); err == nil {
331		return m.IMAPHost
332	}
333	if m.TLS == "starttls" {
334		return net.JoinHostPort(m.IMAPHost, "143")
335	}
336	return net.JoinHostPort(m.IMAPHost, "993")
337}
338
339// MailboxName is Mailbox, INBOX when unset.
340func (m MailInbound) MailboxName() string {
341	if m.Mailbox == "" {
342		return "INBOX"
343	}
344	return m.Mailbox
345}
346
347// Password reads PasswordFile: its first line, which must be all it
348// holds. The file must be readable by its owner alone.
349func (m MailInbound) Password() (string, error) {
350	f, err := os.Open(m.PasswordFile)
351	if err != nil {
352		return "", fmt.Errorf("mail.inbound.password_file: %w", err)
353	}
354	defer f.Close()
355	fi, err := f.Stat()
356	if err != nil {
357		return "", fmt.Errorf("mail.inbound.password_file: %w", err)
358	}
359	if perm := fi.Mode().Perm(); perm&0o077 != 0 {
360		return "", fmt.Errorf("mail.inbound.password_file %s is mode %04o; it must be readable by its owner alone (0600)", m.PasswordFile, perm)
361	}
362	raw, err := io.ReadAll(io.LimitReader(f, 4097))
363	if err != nil {
364		return "", fmt.Errorf("mail.inbound.password_file: %w", err)
365	}
366	pass := strings.TrimRight(string(raw), "\r\n")
367	if pass == "" || len(raw) > 4096 || strings.ContainsAny(pass, "\r\n") {
368		return "", fmt.Errorf("mail.inbound.password_file %s must hold the password on one line", m.PasswordFile)
369	}
370	return pass, nil
371}
372
373func (m MailInbound) validate() []error {
374	if !m.Enabled {
375		return nil
376	}
377	var errs []error
378	for _, f := range []struct{ name, val string }{
379		{"mail.inbound.imap_host", m.IMAPHost},
380		{"mail.inbound.user", m.User},
381		{"mail.inbound.password_file", m.PasswordFile},
382		{"mail.inbound.reply_address", m.ReplyAddress},
383	} {
384		if f.val == "" {
385			errs = append(errs, fmt.Errorf("%s is required when mail.inbound.enabled", f.name))
386		}
387	}
388	if t := m.TLS; t != "" && t != "implicit" && t != "starttls" {
389		errs = append(errs, fmt.Errorf("mail.inbound.tls must be implicit or starttls, got %q: IMAP in clear is not supported", t))
390	}
391	if m.PollInterval != "" {
392		if d, err := time.ParseDuration(m.PollInterval); err != nil || d < 10*time.Second {
393			errs = append(errs, fmt.Errorf("mail.inbound.poll_interval %q must be a duration of at least 10s", m.PollInterval))
394		}
395	}
396	if id := m.TrustedAuthservID; id != "" && strings.ContainsAny(id, " \t;()\"\r\n") {
397		errs = append(errs, fmt.Errorf("mail.inbound.trusted_authserv_id %q must be a bare host name such as mx.google.com", id))
398	}
399	if a := m.ReplyAddress; a != "" {
400		local, domain, ok := strings.Cut(a, "@")
401		if !ok || local == "" || domain == "" || strings.ContainsAny(a, "+ <>\"\r\n") || strings.Contains(domain, "@") {
402			errs = append(errs, fmt.Errorf("mail.inbound.reply_address %q must be a bare address such as reply@example.org, with no + in it", a))
403		}
404	}
405	return errs
406}
407
408// TLSRequired reports whether mail must not go to the relay in clear.
409func (m Mail) TLSRequired() bool {
410	if m.RequireTLS != nil {
411		return *m.RequireTLS
412	}
413	host := m.SMTPHost
414	if h, _, err := net.SplitHostPort(host); err == nil {
415		host = h
416	}
417	host = strings.Trim(host, "[]")
418	if host == "localhost" {
419		return false
420	}
421	ip := net.ParseIP(host)
422	return ip == nil || !ip.IsLoopback()
423}
424
425// Push is APNs delivery to registered Apple devices. A key belongs to a
426// bundle ID, so an instance pushes to the app built under the topic named
427// here and no other; a self-hoster points this at their own key and their
428// own build.
429type Push struct {
430	Enabled bool   `toml:"enabled"`
431	KeyFile string `toml:"key_file"`
432	KeyID   string `toml:"key_id"`
433	TeamID  string `toml:"team_id"`
434	Topic   string `toml:"topic"` // the app's bundle identifier
435	// Environment is a name rather than a URL so a typo cannot aim the
436	// key at a host that is not Apple's.
437	Environment string `toml:"environment"` // production | sandbox
438}
439
440// Host is the APNs endpoint for the configured environment.
441// GITBAY_APNS_HOST overrides it for tests, as GITBAY_SWEEP_TICK does for
442// the retention sweep.
443func (p Push) Host() string {
444	if h := os.Getenv("GITBAY_APNS_HOST"); h != "" {
445		return h
446	}
447	if p.Environment == "sandbox" {
448		return "api.sandbox.push.apple.com"
449	}
450	return "api.push.apple.com"
451}
452
453// LoadAPNSKey reads Apple's .p8 provider key: a PEM-wrapped PKCS#8
454// P-256 private key. Read at startup and validated there, so a
455// misconfigured [push] refuses to start rather than filling a queue
456// nobody is watching.
457func LoadAPNSKey(path string) (*ecdsa.PrivateKey, error) {
458	data, err := os.ReadFile(path)
459	if err != nil {
460		return nil, err
461	}
462	block, _ := pem.Decode(data)
463	if block == nil {
464		return nil, errors.New("not PEM")
465	}
466	any, err := x509.ParsePKCS8PrivateKey(block.Bytes)
467	if err != nil {
468		return nil, err
469	}
470	key, ok := any.(*ecdsa.PrivateKey)
471	if !ok {
472		return nil, errors.New("not an EC private key")
473	}
474	return key, nil
475}
476
477// Backup configures gitbayd admin backup.
478type Backup struct {
479	// AgeRecipients, when set, encrypts every archive to these age
480	// public keys (age1...). The matching identities stay off the host,
481	// so the host writes archives it cannot read.
482	AgeRecipients []string `toml:"age_recipients"`
483}
484
485// Recipients parses AgeRecipients.
486func (b Backup) Recipients() ([]age.Recipient, error) {
487	var rs []age.Recipient
488	for _, s := range b.AgeRecipients {
489		r, err := age.ParseX25519Recipient(s)
490		if err != nil {
491			return nil, fmt.Errorf("backup.age_recipients: %q: %w", s, err)
492		}
493		rs = append(rs, r)
494	}
495	return rs, nil
496}
497
498// Default returns the configuration used when a key is absent from the file.
499func Default() Config {
500	return Config{
501		Server: Server{Root: "/var/lib/gitbay", SecretKeyFile: "/etc/gitbay/secret.key"},
502		SSH:    SSH{Mode: "embedded", Port: 22},
503		HTTP:   HTTP{Addr: ":443", TLS: "acme", ACMEHTTPAddr: ":80"},
504		Web:    Web{Mode: "view_only"},
505		Registration: Registration{
506			Mode: "closed",
507		},
508		GitDaemon: GitDaemon{Port: 9418},
509		Mirrors:   Mirrors{PullIntervalMinutes: 15},
510		Deps:      Deps{CheckIntervalHours: 24},
511		Limits: Limits{
512			MaxPackBytes:    2 << 30, // 2 GiB
513			MaxBlobBytes:    100 << 20,
514			MaxAssetBytes:   512 << 20,
515			MaxSnippetBytes: 1 << 20,
516			CloneTimeoutSec: 3600,
517			SSHAuthRate:     10,
518			APIRate:         120,
519		},
520	}
521}
522
523// Load reads path, applies defaults, and validates. It does not probe the
524// host (see CheckHost) so it is safe in tests and on non-target machines.
525func Load(path string) (Config, error) {
526	cfg := Default()
527	md, err := toml.DecodeFile(path, &cfg)
528	if err != nil {
529		return cfg, err
530	}
531	if u := md.Undecoded(); len(u) > 0 {
532		return cfg, fmt.Errorf("unknown config key %q", u[0].String())
533	}
534	return cfg, cfg.Validate()
535}
536
537// Within reports whether path is dir or below it. Both are compared as
538// cleaned absolute paths (a relative path resolves against the working
539// directory, same as every other path in this config), with symlinks
540// resolved where the path exists on disk, so a path that reaches into dir
541// through a symlink, or through "..", is still reported as inside.
542func Within(dir, path string) bool {
543	dir, path = resolvePath(dir), resolvePath(path)
544	rel, err := filepath.Rel(dir, path)
545	return err == nil && rel != ".." && !strings.HasPrefix(rel, ".."+string(filepath.Separator))
546}
547
548// resolvePath returns path as a cleaned absolute path, resolving symlinks in
549// it. The secret key file commonly does not exist yet (it is created by
550// `gitbayd admin secrets init`), and on this platform /var itself is a
551// symlink, so a whole-path resolution is tried first and, failing that, each
552// ancestor directory in turn, walking up to the nearest one that exists and
553// reattaching the missing suffix — a symlinked ancestor still resolves even
554// though the leaf, or several levels above it, does not exist.
555func resolvePath(path string) string {
556	abs, err := filepath.Abs(path)
557	if err != nil {
558		return filepath.Clean(path)
559	}
560	dir := abs
561	var suffix []string
562	for {
563		if resolved, err := filepath.EvalSymlinks(dir); err == nil {
564			for i := len(suffix) - 1; i >= 0; i-- {
565				resolved = filepath.Join(resolved, suffix[i])
566			}
567			return resolved
568		}
569		parent := filepath.Dir(dir)
570		if parent == dir {
571			return abs
572		}
573		suffix = append(suffix, filepath.Base(dir))
574		dir = parent
575	}
576}
577
578func oneOf(field, val string, allowed ...string) error {
579	for _, a := range allowed {
580		if val == a {
581			return nil
582		}
583	}
584	return fmt.Errorf("%s must be one of %v, got %q", field, allowed, val)
585}
586
587// Validate applies the static contradiction checks from the plan.
588func (c Config) Validate() error {
589	var errs []error
590
591	if c.Server.Root == "" {
592		errs = append(errs, errors.New("server.root is required"))
593	}
594	if d := c.Pages.Domain; d != "" {
595		if d == c.SiteHost() {
596			errs = append(errs, errors.New("pages.domain must differ from the site host: pages serve repo-authored scripts, which must not run on the forge's origin"))
597		}
598		if strings.HasSuffix(c.SiteHost(), "."+d) {
599			errs = append(errs, errors.New("pages.domain must not be a parent of the site host"))
600		}
601	}
602	if c.Server.SiteURL == "" {
603		errs = append(errs, errors.New("server.site_url is required"))
604	}
605	switch {
606	case c.Server.SecretKeyFile == "":
607		errs = append(errs, errors.New("server.secret_key_file is required"))
608	case Within(c.Server.Root, c.Server.SecretKeyFile):
609		errs = append(errs, fmt.Errorf("server.secret_key_file %q is inside server.root: backups of the root would carry the key beside the values it seals", c.Server.SecretKeyFile))
610	}
611	if err := oneOf("ssh.mode", c.SSH.Mode, "embedded", "system"); err != nil {
612		errs = append(errs, err)
613	}
614	if c.Registration.PendingExpiry != "" {
615		if d, err := time.ParseDuration(c.Registration.PendingExpiry); err != nil || d <= 0 {
616			errs = append(errs, fmt.Errorf("registration.pending_expiry %q must be a positive duration such as 168h", c.Registration.PendingExpiry))
617		}
618	}
619	if c.Limits.MaxReposPerUser < 0 || c.Limits.MaxBytesPerUser < 0 || c.Limits.MaxSnippetsPerUser < 0 {
620		errs = append(errs, errors.New("limits.max_repos_per_user, max_bytes_per_user and max_snippets_per_user must not be negative"))
621	}
622	if w := c.Limits.PackQueueWait; w != "" {
623		if d, err := time.ParseDuration(w); err != nil || d <= 0 {
624			errs = append(errs, fmt.Errorf("limits.pack_queue_wait %q must be a positive duration such as 60s", w))
625		}
626	}
627	if c.Push.Enabled {
628		for _, f := range []struct{ name, val string }{
629			{"push.key_file", c.Push.KeyFile},
630			{"push.key_id", c.Push.KeyID},
631			{"push.team_id", c.Push.TeamID},
632			{"push.topic", c.Push.Topic},
633		} {
634			if f.val == "" {
635				errs = append(errs, fmt.Errorf("%s is required when push.enabled", f.name))
636			}
637		}
638		if err := oneOf("push.environment", c.Push.Environment, "production", "sandbox"); err != nil {
639			errs = append(errs, err)
640		}
641		if c.Push.KeyFile != "" {
642			if _, err := LoadAPNSKey(c.Push.KeyFile); err != nil {
643				errs = append(errs, fmt.Errorf("push.key_file: %w", err))
644			}
645		}
646	}
647	if c.SSH.Port < 1 || c.SSH.Port > 65535 {
648		errs = append(errs, fmt.Errorf("ssh.port %d out of range", c.SSH.Port))
649	}
650	if err := oneOf("http.tls", c.HTTP.TLS, "acme", "files", "off"); err != nil {
651		errs = append(errs, err)
652	}
653	if _, err := c.HTTP.TrustedProxyNets(); err != nil {
654		errs = append(errs, err)
655	}
656	if c.HTTP.TLS == "files" && (c.HTTP.CertFile == "" || c.HTTP.KeyFile == "") {
657		errs = append(errs, errors.New("http.tls = \"files\" requires cert_file and key_file"))
658	}
659	if c.HTTP.TLS == "acme" {
660		host := c.SiteHost()
661		switch {
662		case !strings.HasPrefix(c.Server.SiteURL, "https://"):
663			errs = append(errs, errors.New("http.tls = \"acme\" requires an https:// site_url: certificates are issued for that host"))
664		case host == "" || host == "localhost" || net.ParseIP(host) != nil:
665			errs = append(errs, fmt.Errorf("http.tls = \"acme\" cannot issue a certificate for %q: use a public DNS name in site_url", host))
666		}
667	}
668	if err := oneOf("web.mode", c.Web.Mode, "view_only", "accounts"); err != nil {
669		errs = append(errs, err)
670	}
671	if err := oneOf("registration.mode", c.Registration.Mode, "closed", "invite", "open"); err != nil {
672		errs = append(errs, err)
673	}
674
675	for module, repo := range c.GoImport {
676		host, _, ok := strings.Cut(module, "/")
677		if !ok || host == "" || !strings.Contains(host, ".") {
678			errs = append(errs, fmt.Errorf("go_import key %q must be host/path (e.g. gitbay.org/gitbay)", module))
679		}
680		if parts := strings.Split(repo, "/"); len(parts) != 2 || parts[0] == "" || parts[1] == "" {
681			errs = append(errs, fmt.Errorf("go_import value %q must be owner/name", repo))
682		}
683	}
684
685	if _, err := c.Backup.Recipients(); err != nil {
686		errs = append(errs, err)
687	}
688
689	// Contradictions.
690	if c.Mail.SMTPHost != "" && c.Mail.From == "" {
691		errs = append(errs, errors.New("[mail] from is required when smtp_host is set"))
692	}
693	if t := c.Mail.TLS; t != "" && t != "starttls" && t != "implicit" {
694		errs = append(errs, fmt.Errorf("mail.tls must be starttls or implicit, got %q", t))
695	}
696	errs = append(errs, c.Mail.Inbound.validate()...)
697	if c.Mail.Inbound.Enabled && c.Mail.SMTPHost == "" {
698		errs = append(errs, errors.New("mail.inbound.enabled requires [mail] smtp_host: replies answer notification mail, which is not sent without SMTP"))
699	}
700	if c.Registration.Mode != "closed" && c.Mail.SMTPHost == "" {
701		errs = append(errs, fmt.Errorf(
702			"registration.mode = %q requires [mail] smtp_host: email verification cannot run without SMTP",
703			c.Registration.Mode))
704	}
705	if c.Registration.NotifyAdmin && c.Mail.SMTPHost == "" {
706		errs = append(errs, errors.New(
707			"registration.notify_admin = true requires [mail] smtp_host: there is nowhere to send the notice"))
708	}
709	if c.SSH.Mode == "system" && c.Registration.Mode != "closed" {
710		errs = append(errs, fmt.Errorf(
711			"ssh.mode = \"system\" requires registration.mode = \"closed\": host sshd rejects unknown keys before the dispatcher runs, so registration by unknown key is impossible"))
712	}
713	if c.Web.PasswordAuth && c.Web.Mode == "view_only" {
714		errs = append(errs, errors.New(
715			"web.password_auth = true is meaningless with web.mode = \"view_only\": no login route exists"))
716	}
717	if c.Web.PasswordAuth && c.Web.Mode == "accounts" {
718		errs = append(errs, errors.New(
719			"web.password_auth is not implemented yet; browser sessions are minted over SSH (gitbay web login)"))
720	}
721
722	return errors.Join(errs...)
723}
724
725// SiteHost returns the bare hostname from site_url (no scheme, port, path).
726func (c Config) SiteHost() string {
727	h := strings.TrimPrefix(strings.TrimPrefix(c.Server.SiteURL, "https://"), "http://")
728	h = strings.TrimSuffix(h, "/")
729	if i := strings.IndexByte(h, '/'); i >= 0 {
730		h = h[:i]
731	}
732	if host, _, err := net.SplitHostPort(h); err == nil {
733		return host
734	}
735	return h
736}
737
738// CheckHost performs environment probes that only make sense on the target
739// machine: port availability for the embedded listener and root existence.
740func (c Config) CheckHost() error {
741	var errs []error
742
743	if st, err := os.Stat(c.Server.Root); err != nil {
744		errs = append(errs, fmt.Errorf("server.root: %w", err))
745	} else if !st.IsDir() {
746		errs = append(errs, fmt.Errorf("server.root %q is not a directory", c.Server.Root))
747	}
748
749	if c.SSH.Mode == "embedded" {
750		addr := net.JoinHostPort("", strconv.Itoa(c.SSH.Port))
751		ln, err := net.Listen("tcp", addr)
752		if err != nil {
753			errs = append(errs, fmt.Errorf("ssh.port %d is not bindable (already in use by another daemon?): %w", c.SSH.Port, err))
754		} else {
755			ln.Close()
756		}
757	}
758
759	return errors.Join(errs...)
760}
761
762// TrustedProxyNets parses http.trusted_proxies; a bare address is a /32
763// or /128.
764func (h HTTP) TrustedProxyNets() ([]*net.IPNet, error) {
765	var nets []*net.IPNet
766	for _, p := range h.TrustedProxies {
767		if _, n, err := net.ParseCIDR(p); err == nil {
768			nets = append(nets, n)
769			continue
770		}
771		ip := net.ParseIP(p)
772		if ip == nil {
773			return nil, fmt.Errorf("http.trusted_proxies: %q is not an address or CIDR", p)
774		}
775		bits := 32
776		if ip.To4() == nil {
777			bits = 128
778		}
779		nets = append(nets, &net.IPNet{IP: ip, Mask: net.CIDRMask(bits, bits)})
780	}
781	return nets, nil
782}