internal/config/config.go

491 lines · 17561 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	"net"
 11	"os"
 12	"strconv"
 13	"strings"
 14	"time"
 15
 16	"github.com/BurntSushi/toml"
 17)
 18
 19// DefaultWriteRate is the per-account write budget when the config leaves
 20// write_rate at zero: generous for a person at a terminal, and a bound on
 21// what one account can enqueue — every write also queues notification mail
 22// and webhook deliveries.
 23const DefaultWriteRate = 60
 24
 25type Config struct {
 26	Server       Server       `toml:"server"`
 27	SSH          SSH          `toml:"ssh"`
 28	HTTP         HTTP         `toml:"http"`
 29	GitDaemon    GitDaemon    `toml:"git_daemon"`
 30	Web          Web          `toml:"web"`
 31	Registration Registration `toml:"registration"`
 32	API          API          `toml:"api"`
 33	Webhooks     Webhooks     `toml:"webhooks"`
 34	Pages        Pages        `toml:"pages"`
 35	LFS          LFS          `toml:"lfs"`
 36	Limits       Limits       `toml:"limits"`
 37	Mail         Mail         `toml:"mail"`
 38	Mirrors      Mirrors      `toml:"mirrors"`
 39	Deps         Deps         `toml:"deps"`
 40	Retention    Retention    `toml:"retention"`
 41	Push         Push         `toml:"push"`
 42	// GoImport maps vanity Go module paths to repositories, e.g.
 43	// "gitbay.org/gitbay" = "krz/gitbay". Requests carrying ?go-get=1
 44	// under a mapped path get a go-import meta tag.
 45	GoImport map[string]string `toml:"go_import"`
 46}
 47
 48type Server struct {
 49	Root    string `toml:"root"`
 50	SiteURL string `toml:"site_url"`
 51
 52	// SourceRepo names the repository this instance develops itself in, as
 53	// "owner/name". When set, startup warns if the running build's commit is
 54	// not on that repository's default branch. Empty disables the check, which
 55	// is right for any instance that does not host its own source.
 56	SourceRepo string `toml:"source_repo"`
 57}
 58
 59type SSH struct {
 60	Mode     string   `toml:"mode"` // embedded | system
 61	Port     int      `toml:"port"`
 62	HostKeys []string `toml:"host_keys"`
 63}
 64
 65type HTTP struct {
 66	Addr     string `toml:"addr"`
 67	TLS      string `toml:"tls"` // acme | files | off
 68	CertFile string `toml:"cert_file"`
 69	KeyFile  string `toml:"key_file"`
 70	// ACME (Let's Encrypt by default). Certificates are cached under
 71	// server.root/acme. acme_http_addr serves HTTP-01 challenges and
 72	// redirects to HTTPS; "off" disables it (TLS-ALPN-01 on the HTTPS
 73	// port still works).
 74	ACMEEmail    string `toml:"acme_email"`
 75	ACMEHTTPAddr string `toml:"acme_http_addr"`
 76	// TrustedProxies are the addresses or CIDRs of reverse proxies in front
 77	// of this process. A request from one of them is attributed to the
 78	// last X-Forwarded-For hop that is not itself a trusted proxy; from
 79	// anyone else the peer address is the client and the header is
 80	// ignored. Empty means no proxy, which is how gitbayd is deployed by
 81	// default: it terminates TLS itself.
 82	TrustedProxies []string `toml:"trusted_proxies,omitempty"`
 83}
 84
 85type GitDaemon struct {
 86	Enabled bool `toml:"enabled"`
 87	Port    int  `toml:"port"`
 88}
 89
 90type Web struct {
 91	Mode         string `toml:"mode"` // view_only | accounts
 92	PasswordAuth bool   `toml:"password_auth"`
 93	// Title is the instance's display name in the header and page titles.
 94	// Empty falls back to the site host.
 95	Title string `toml:"title"`
 96	// PrivacyNotice is operator-provided text shown on /privacy under the
 97	// fixed project-level statement. Plain text; blank paragraphs split.
 98	PrivacyNotice string `toml:"privacy_notice"`
 99}
100
101type Registration struct {
102	Mode string `toml:"mode"` // closed | invite | open
103	// PendingExpiry is how long a self-registered account may stay
104	// unverified before it is removed, as a duration ("168h"). Empty
105	// keeps such accounts forever.
106	PendingExpiry string `toml:"pending_expiry"`
107	// NotifyAdmin mails the instance's admins when an account becomes
108	// active: an invite redeemed, or an open-mode signup that verified
109	// its address. The unverified row an open signup creates is not
110	// reported — anyone can post the form, so mailing on that would
111	// aim a flood at the admins (#234).
112	NotifyAdmin bool `toml:"notify_admin"`
113}
114
115// PendingExpiryDuration parses PendingExpiry; zero means never.
116func (r Registration) PendingExpiryDuration() time.Duration {
117	d, _ := time.ParseDuration(r.PendingExpiry)
118	return d
119}
120
121// Retention is how long the append-only tables keep a row. Each is a
122// duration string ("2160h"); empty or zero keeps forever, which is what
123// an instance that has never configured this gets. Expired sessions and
124// tokens are swept regardless: they are dead weight the moment they
125// expire and no setting makes them worth keeping.
126type Retention struct {
127	Audit             string `toml:"audit"`
128	Events            string `toml:"events"`
129	WebhookDeliveries string `toml:"webhook_deliveries"`
130	// Mail is the outbound queue: rows already sent or given up on.
131	Mail string `toml:"mail"`
132	// Push is the outbound device queue: rows already sent or given up on.
133	Push string `toml:"push"`
134}
135
136// Durations parses the five, mapping each to zero when unset or bad.
137func (r Retention) Durations() (audit, events, deliveries, mail, push time.Duration) {
138	parse := func(s string) time.Duration {
139		d, err := time.ParseDuration(s)
140		if err != nil || d < 0 {
141			return 0
142		}
143		return d
144	}
145	return parse(r.Audit), parse(r.Events), parse(r.WebhookDeliveries), parse(r.Mail), parse(r.Push)
146}
147
148// LFS stores large-file objects content-addressed under Root (default
149// <server.root>/lfs). MaxObjectBytes caps a single object; 0 means the
150// 512MB default.
151type LFS struct {
152	Root           string `toml:"root"`
153	MaxObjectBytes int64  `toml:"max_object_bytes"`
154}
155
156// Pages serves each public repo's `pages` branch as a static site on
157// <owner>.<domain> — a separate origin, so page-authored scripts never run
158// on the forge's own host. Empty domain disables the feature.
159type Pages struct {
160	Domain string `toml:"domain"`
161}
162
163// API controls the HTTPS/JSON control-plane API (bearer tokens minted over
164// SSH). Off by default: an instance that never enables it has no
165// credential-bearing HTTP surface at all.
166type API struct {
167	Enabled bool `toml:"enabled"`
168}
169
170// Webhooks controls outbound delivery. AllowLocal permits endpoints on
171// loopback/private addresses (off by default: SSRF).
172type Webhooks struct {
173	AllowLocal bool `toml:"allow_local"`
174}
175
176type Mirrors struct {
177	PullIntervalMinutes int `toml:"pull_interval_minutes"`
178}
179
180// Deps configures the dependency-update sweep. It runs only for repos that
181// have opted in with `repo deps enable`, because checking a private repo
182// tells a public registry what it depends on.
183type Deps struct {
184	CheckIntervalHours int `toml:"check_interval_hours"`
185}
186
187type Limits struct {
188	MaxPackBytes    int64 `toml:"max_pack_bytes"`
189	MaxBlobBytes    int64 `toml:"max_blob_bytes"`
190	MaxAssetBytes   int64 `toml:"max_asset_bytes"`   // per release asset
191	MaxSnippetBytes int64 `toml:"max_snippet_bytes"` // per snippet file
192	// MaxSnippetsPerUser caps snippets an account may own. 0 means
193	// unlimited, like MaxReposPerUser.
194	MaxSnippetsPerUser int `toml:"max_snippets_per_user"`
195	CloneTimeoutSec    int `toml:"clone_timeout"`
196	SSHAuthRate        int `toml:"ssh_auth_rate"`
197	// APIRate is sustained JSON-API requests per minute per caller; writes
198	// draw on a tenth of it. 0 uses the default.
199	APIRate int `toml:"api_rate"`
200	// WriteRate is sustained mutating commands per minute per account,
201	// counted in the dispatcher so every surface shares one budget. 0 uses
202	// the default; a negative value turns the limit off.
203	WriteRate int `toml:"write_rate"`
204	// Per-account quotas on what a user owns directly (organizations are
205	// not capped). 0 means unlimited; admin user limits overrides per
206	// account.
207	MaxReposPerUser int   `toml:"max_repos_per_user"`
208	MaxBytesPerUser int64 `toml:"max_bytes_per_user"`
209}
210
211type Mail struct {
212	SMTPHost string `toml:"smtp_host"` // host:port (port defaults to 587)
213	From     string `toml:"from"`
214	SMTPUser string `toml:"smtp_user,omitempty"`
215	SMTPPass string `toml:"smtp_pass,omitempty"`
216}
217
218// Push is APNs delivery to registered Apple devices. A key belongs to a
219// bundle ID, so an instance pushes to the app built under the topic named
220// here and no other; a self-hoster points this at their own key and their
221// own build.
222type Push struct {
223	Enabled bool   `toml:"enabled"`
224	KeyFile string `toml:"key_file"`
225	KeyID   string `toml:"key_id"`
226	TeamID  string `toml:"team_id"`
227	Topic   string `toml:"topic"` // the app's bundle identifier
228	// Environment is a name rather than a URL so a typo cannot aim the
229	// key at a host that is not Apple's.
230	Environment string `toml:"environment"` // production | sandbox
231}
232
233// Host is the APNs endpoint for the configured environment.
234// GITBAY_APNS_HOST overrides it for tests, as GITBAY_SWEEP_TICK does for
235// the retention sweep.
236func (p Push) Host() string {
237	if h := os.Getenv("GITBAY_APNS_HOST"); h != "" {
238		return h
239	}
240	if p.Environment == "sandbox" {
241		return "api.sandbox.push.apple.com"
242	}
243	return "api.push.apple.com"
244}
245
246// LoadAPNSKey reads Apple's .p8 provider key: a PEM-wrapped PKCS#8
247// P-256 private key. Read at startup and validated there, so a
248// misconfigured [push] refuses to start rather than filling a queue
249// nobody is watching.
250func LoadAPNSKey(path string) (*ecdsa.PrivateKey, error) {
251	data, err := os.ReadFile(path)
252	if err != nil {
253		return nil, err
254	}
255	block, _ := pem.Decode(data)
256	if block == nil {
257		return nil, errors.New("not PEM")
258	}
259	any, err := x509.ParsePKCS8PrivateKey(block.Bytes)
260	if err != nil {
261		return nil, err
262	}
263	key, ok := any.(*ecdsa.PrivateKey)
264	if !ok {
265		return nil, errors.New("not an EC private key")
266	}
267	return key, nil
268}
269
270// Default returns the configuration used when a key is absent from the file.
271func Default() Config {
272	return Config{
273		Server: Server{Root: "/var/lib/gitbay"},
274		SSH:    SSH{Mode: "embedded", Port: 22},
275		HTTP:   HTTP{Addr: ":443", TLS: "acme", ACMEHTTPAddr: ":80"},
276		Web:    Web{Mode: "view_only"},
277		Registration: Registration{
278			Mode: "closed",
279		},
280		GitDaemon: GitDaemon{Port: 9418},
281		Mirrors:   Mirrors{PullIntervalMinutes: 15},
282		Deps:      Deps{CheckIntervalHours: 24},
283		Limits: Limits{
284			MaxPackBytes:    2 << 30, // 2 GiB
285			MaxBlobBytes:    100 << 20,
286			MaxAssetBytes:   512 << 20,
287			MaxSnippetBytes: 1 << 20,
288			CloneTimeoutSec: 3600,
289			SSHAuthRate:     10,
290			APIRate:         120,
291		},
292	}
293}
294
295// Load reads path, applies defaults, and validates. It does not probe the
296// host (see CheckHost) so it is safe in tests and on non-target machines.
297func Load(path string) (Config, error) {
298	cfg := Default()
299	md, err := toml.DecodeFile(path, &cfg)
300	if err != nil {
301		return cfg, err
302	}
303	if u := md.Undecoded(); len(u) > 0 {
304		return cfg, fmt.Errorf("unknown config key %q", u[0].String())
305	}
306	return cfg, cfg.Validate()
307}
308
309func oneOf(field, val string, allowed ...string) error {
310	for _, a := range allowed {
311		if val == a {
312			return nil
313		}
314	}
315	return fmt.Errorf("%s must be one of %v, got %q", field, allowed, val)
316}
317
318// Validate applies the static contradiction checks from the plan.
319func (c Config) Validate() error {
320	var errs []error
321
322	if c.Server.Root == "" {
323		errs = append(errs, errors.New("server.root is required"))
324	}
325	if d := c.Pages.Domain; d != "" {
326		if d == c.SiteHost() {
327			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"))
328		}
329		if strings.HasSuffix(c.SiteHost(), "."+d) {
330			errs = append(errs, errors.New("pages.domain must not be a parent of the site host"))
331		}
332	}
333	if c.Server.SiteURL == "" {
334		errs = append(errs, errors.New("server.site_url is required"))
335	}
336	if err := oneOf("ssh.mode", c.SSH.Mode, "embedded", "system"); err != nil {
337		errs = append(errs, err)
338	}
339	if c.Registration.PendingExpiry != "" {
340		if d, err := time.ParseDuration(c.Registration.PendingExpiry); err != nil || d <= 0 {
341			errs = append(errs, fmt.Errorf("registration.pending_expiry %q must be a positive duration such as 168h", c.Registration.PendingExpiry))
342		}
343	}
344	if c.Limits.MaxReposPerUser < 0 || c.Limits.MaxBytesPerUser < 0 || c.Limits.MaxSnippetsPerUser < 0 {
345		errs = append(errs, errors.New("limits.max_repos_per_user, max_bytes_per_user and max_snippets_per_user must not be negative"))
346	}
347	if c.Push.Enabled {
348		for _, f := range []struct{ name, val string }{
349			{"push.key_file", c.Push.KeyFile},
350			{"push.key_id", c.Push.KeyID},
351			{"push.team_id", c.Push.TeamID},
352			{"push.topic", c.Push.Topic},
353		} {
354			if f.val == "" {
355				errs = append(errs, fmt.Errorf("%s is required when push.enabled", f.name))
356			}
357		}
358		if err := oneOf("push.environment", c.Push.Environment, "production", "sandbox"); err != nil {
359			errs = append(errs, err)
360		}
361		if c.Push.KeyFile != "" {
362			if _, err := LoadAPNSKey(c.Push.KeyFile); err != nil {
363				errs = append(errs, fmt.Errorf("push.key_file: %w", err))
364			}
365		}
366	}
367	if c.SSH.Port < 1 || c.SSH.Port > 65535 {
368		errs = append(errs, fmt.Errorf("ssh.port %d out of range", c.SSH.Port))
369	}
370	if err := oneOf("http.tls", c.HTTP.TLS, "acme", "files", "off"); err != nil {
371		errs = append(errs, err)
372	}
373	if _, err := c.HTTP.TrustedProxyNets(); err != nil {
374		errs = append(errs, err)
375	}
376	if c.HTTP.TLS == "files" && (c.HTTP.CertFile == "" || c.HTTP.KeyFile == "") {
377		errs = append(errs, errors.New("http.tls = \"files\" requires cert_file and key_file"))
378	}
379	if c.HTTP.TLS == "acme" {
380		host := c.SiteHost()
381		switch {
382		case !strings.HasPrefix(c.Server.SiteURL, "https://"):
383			errs = append(errs, errors.New("http.tls = \"acme\" requires an https:// site_url: certificates are issued for that host"))
384		case host == "" || host == "localhost" || net.ParseIP(host) != nil:
385			errs = append(errs, fmt.Errorf("http.tls = \"acme\" cannot issue a certificate for %q: use a public DNS name in site_url", host))
386		}
387	}
388	if err := oneOf("web.mode", c.Web.Mode, "view_only", "accounts"); err != nil {
389		errs = append(errs, err)
390	}
391	if err := oneOf("registration.mode", c.Registration.Mode, "closed", "invite", "open"); err != nil {
392		errs = append(errs, err)
393	}
394
395	for module, repo := range c.GoImport {
396		host, _, ok := strings.Cut(module, "/")
397		if !ok || host == "" || !strings.Contains(host, ".") {
398			errs = append(errs, fmt.Errorf("go_import key %q must be host/path (e.g. gitbay.org/gitbay)", module))
399		}
400		if parts := strings.Split(repo, "/"); len(parts) != 2 || parts[0] == "" || parts[1] == "" {
401			errs = append(errs, fmt.Errorf("go_import value %q must be owner/name", repo))
402		}
403	}
404
405	// Contradictions.
406	if c.Mail.SMTPHost != "" && c.Mail.From == "" {
407		errs = append(errs, errors.New("[mail] from is required when smtp_host is set"))
408	}
409	if c.Registration.Mode != "closed" && c.Mail.SMTPHost == "" {
410		errs = append(errs, fmt.Errorf(
411			"registration.mode = %q requires [mail] smtp_host: email verification cannot run without SMTP",
412			c.Registration.Mode))
413	}
414	if c.Registration.NotifyAdmin && c.Mail.SMTPHost == "" {
415		errs = append(errs, errors.New(
416			"registration.notify_admin = true requires [mail] smtp_host: there is nowhere to send the notice"))
417	}
418	if c.SSH.Mode == "system" && c.Registration.Mode != "closed" {
419		errs = append(errs, fmt.Errorf(
420			"ssh.mode = \"system\" requires registration.mode = \"closed\": host sshd rejects unknown keys before the dispatcher runs, so registration by unknown key is impossible"))
421	}
422	if c.Web.PasswordAuth && c.Web.Mode == "view_only" {
423		errs = append(errs, errors.New(
424			"web.password_auth = true is meaningless with web.mode = \"view_only\": no login route exists"))
425	}
426	if c.Web.PasswordAuth && c.Web.Mode == "accounts" {
427		errs = append(errs, errors.New(
428			"web.password_auth is not implemented yet; browser sessions are minted over SSH (gitbay web login)"))
429	}
430
431	return errors.Join(errs...)
432}
433
434// SiteHost returns the bare hostname from site_url (no scheme, port, path).
435func (c Config) SiteHost() string {
436	h := strings.TrimPrefix(strings.TrimPrefix(c.Server.SiteURL, "https://"), "http://")
437	h = strings.TrimSuffix(h, "/")
438	if i := strings.IndexByte(h, '/'); i >= 0 {
439		h = h[:i]
440	}
441	if host, _, err := net.SplitHostPort(h); err == nil {
442		return host
443	}
444	return h
445}
446
447// CheckHost performs environment probes that only make sense on the target
448// machine: port availability for the embedded listener and root existence.
449func (c Config) CheckHost() error {
450	var errs []error
451
452	if st, err := os.Stat(c.Server.Root); err != nil {
453		errs = append(errs, fmt.Errorf("server.root: %w", err))
454	} else if !st.IsDir() {
455		errs = append(errs, fmt.Errorf("server.root %q is not a directory", c.Server.Root))
456	}
457
458	if c.SSH.Mode == "embedded" {
459		addr := net.JoinHostPort("", strconv.Itoa(c.SSH.Port))
460		ln, err := net.Listen("tcp", addr)
461		if err != nil {
462			errs = append(errs, fmt.Errorf("ssh.port %d is not bindable (already in use by another daemon?): %w", c.SSH.Port, err))
463		} else {
464			ln.Close()
465		}
466	}
467
468	return errors.Join(errs...)
469}
470
471// TrustedProxyNets parses http.trusted_proxies; a bare address is a /32
472// or /128.
473func (h HTTP) TrustedProxyNets() ([]*net.IPNet, error) {
474	var nets []*net.IPNet
475	for _, p := range h.TrustedProxies {
476		if _, n, err := net.ParseCIDR(p); err == nil {
477			nets = append(nets, n)
478			continue
479		}
480		ip := net.ParseIP(p)
481		if ip == nil {
482			return nil, fmt.Errorf("http.trusted_proxies: %q is not an address or CIDR", p)
483		}
484		bits := 32
485		if ip.To4() == nil {
486			bits = 128
487		}
488		nets = append(nets, &net.IPNet{IP: ip, Mask: net.CIDRMask(bits, bits)})
489	}
490	return nets, nil
491}