internal/config/config.go
227 lines · 7155 bytes
1// Package config loads and validates the gitbayd server configuration.
2package config
3
4import (
5 "errors"
6 "fmt"
7 "net"
8 "os"
9 "strconv"
10 "strings"
11
12 "github.com/BurntSushi/toml"
13)
14
15type Config struct {
16 Server Server `toml:"server"`
17 SSH SSH `toml:"ssh"`
18 HTTP HTTP `toml:"http"`
19 GitDaemon GitDaemon `toml:"git_daemon"`
20 Web Web `toml:"web"`
21 Registration Registration `toml:"registration"`
22 API API `toml:"api"`
23 Limits Limits `toml:"limits"`
24 Mail Mail `toml:"mail"`
25}
26
27type Server struct {
28 Root string `toml:"root"`
29 SiteURL string `toml:"site_url"`
30}
31
32type SSH struct {
33 Mode string `toml:"mode"` // embedded | system
34 Port int `toml:"port"`
35 HostKeys []string `toml:"host_keys"`
36}
37
38type HTTP struct {
39 Addr string `toml:"addr"`
40 TLS string `toml:"tls"` // acme | files | off
41 CertFile string `toml:"cert_file"`
42 KeyFile string `toml:"key_file"`
43 // ACME (Let's Encrypt by default). Certificates are cached under
44 // server.root/acme. acme_http_addr serves HTTP-01 challenges and
45 // redirects to HTTPS; "off" disables it (TLS-ALPN-01 on the HTTPS
46 // port still works).
47 ACMEEmail string `toml:"acme_email"`
48 ACMEHTTPAddr string `toml:"acme_http_addr"`
49}
50
51type GitDaemon struct {
52 Enabled bool `toml:"enabled"`
53 Port int `toml:"port"`
54}
55
56type Web struct {
57 Mode string `toml:"mode"` // view_only | accounts
58 PasswordAuth bool `toml:"password_auth"`
59}
60
61type Registration struct {
62 Mode string `toml:"mode"` // closed | invite | open
63}
64
65// API controls the HTTPS/JSON control-plane API (bearer tokens minted over
66// SSH). Off by default: an instance that never enables it has no
67// credential-bearing HTTP surface at all.
68type API struct {
69 Enabled bool `toml:"enabled"`
70}
71
72type Limits struct {
73 MaxPackBytes int64 `toml:"max_pack_bytes"`
74 MaxBlobBytes int64 `toml:"max_blob_bytes"`
75 CloneTimeoutSec int `toml:"clone_timeout"`
76 SSHAuthRate int `toml:"ssh_auth_rate"`
77}
78
79type Mail struct {
80 SMTPHost string `toml:"smtp_host"` // host:port (port defaults to 587)
81 From string `toml:"from"`
82 SMTPUser string `toml:"smtp_user,omitempty"`
83 SMTPPass string `toml:"smtp_pass,omitempty"`
84}
85
86// Default returns the configuration used when a key is absent from the file.
87func Default() Config {
88 return Config{
89 Server: Server{Root: "/var/lib/gitbay"},
90 SSH: SSH{Mode: "embedded", Port: 22},
91 HTTP: HTTP{Addr: ":443", TLS: "acme", ACMEHTTPAddr: ":80"},
92 Web: Web{Mode: "view_only"},
93 Registration: Registration{
94 Mode: "closed",
95 },
96 GitDaemon: GitDaemon{Port: 9418},
97 Limits: Limits{
98 MaxPackBytes: 2 << 30, // 2 GiB
99 MaxBlobBytes: 100 << 20,
100 CloneTimeoutSec: 3600,
101 SSHAuthRate: 10,
102 },
103 }
104}
105
106// Load reads path, applies defaults, and validates. It does not probe the
107// host (see CheckHost) so it is safe in tests and on non-target machines.
108func Load(path string) (Config, error) {
109 cfg := Default()
110 md, err := toml.DecodeFile(path, &cfg)
111 if err != nil {
112 return cfg, err
113 }
114 if u := md.Undecoded(); len(u) > 0 {
115 return cfg, fmt.Errorf("unknown config key %q", u[0].String())
116 }
117 return cfg, cfg.Validate()
118}
119
120func oneOf(field, val string, allowed ...string) error {
121 for _, a := range allowed {
122 if val == a {
123 return nil
124 }
125 }
126 return fmt.Errorf("%s must be one of %v, got %q", field, allowed, val)
127}
128
129// Validate applies the static contradiction checks from the plan.
130func (c Config) Validate() error {
131 var errs []error
132
133 if c.Server.Root == "" {
134 errs = append(errs, errors.New("server.root is required"))
135 }
136 if c.Server.SiteURL == "" {
137 errs = append(errs, errors.New("server.site_url is required"))
138 }
139 if err := oneOf("ssh.mode", c.SSH.Mode, "embedded", "system"); err != nil {
140 errs = append(errs, err)
141 }
142 if c.SSH.Port < 1 || c.SSH.Port > 65535 {
143 errs = append(errs, fmt.Errorf("ssh.port %d out of range", c.SSH.Port))
144 }
145 if err := oneOf("http.tls", c.HTTP.TLS, "acme", "files", "off"); err != nil {
146 errs = append(errs, err)
147 }
148 if c.HTTP.TLS == "files" && (c.HTTP.CertFile == "" || c.HTTP.KeyFile == "") {
149 errs = append(errs, errors.New("http.tls = \"files\" requires cert_file and key_file"))
150 }
151 if c.HTTP.TLS == "acme" {
152 host := c.SiteHost()
153 switch {
154 case !strings.HasPrefix(c.Server.SiteURL, "https://"):
155 errs = append(errs, errors.New("http.tls = \"acme\" requires an https:// site_url: certificates are issued for that host"))
156 case host == "" || host == "localhost" || net.ParseIP(host) != nil:
157 errs = append(errs, fmt.Errorf("http.tls = \"acme\" cannot issue a certificate for %q: use a public DNS name in site_url", host))
158 }
159 }
160 if err := oneOf("web.mode", c.Web.Mode, "view_only", "accounts"); err != nil {
161 errs = append(errs, err)
162 }
163 if err := oneOf("registration.mode", c.Registration.Mode, "closed", "invite", "open"); err != nil {
164 errs = append(errs, err)
165 }
166
167 // Contradictions.
168 if c.Mail.SMTPHost != "" && c.Mail.From == "" {
169 errs = append(errs, errors.New("[mail] from is required when smtp_host is set"))
170 }
171 if c.Registration.Mode != "closed" && c.Mail.SMTPHost == "" {
172 errs = append(errs, fmt.Errorf(
173 "registration.mode = %q requires [mail] smtp_host: email verification cannot run without SMTP",
174 c.Registration.Mode))
175 }
176 if c.SSH.Mode == "system" && c.Registration.Mode != "closed" {
177 errs = append(errs, fmt.Errorf(
178 "ssh.mode = \"system\" requires registration.mode = \"closed\": host sshd rejects unknown keys before the dispatcher runs, so registration by unknown key is impossible"))
179 }
180 if c.Web.PasswordAuth && c.Web.Mode == "view_only" {
181 errs = append(errs, errors.New(
182 "web.password_auth = true is meaningless with web.mode = \"view_only\": no login route exists"))
183 }
184 if c.Web.PasswordAuth && c.Web.Mode == "accounts" {
185 errs = append(errs, errors.New(
186 "web.password_auth is not implemented yet; browser sessions are minted over SSH (gitbay web login)"))
187 }
188
189 return errors.Join(errs...)
190}
191
192// SiteHost returns the bare hostname from site_url (no scheme, port, path).
193func (c Config) SiteHost() string {
194 h := strings.TrimPrefix(strings.TrimPrefix(c.Server.SiteURL, "https://"), "http://")
195 h = strings.TrimSuffix(h, "/")
196 if i := strings.IndexByte(h, '/'); i >= 0 {
197 h = h[:i]
198 }
199 if host, _, err := net.SplitHostPort(h); err == nil {
200 return host
201 }
202 return h
203}
204
205// CheckHost performs environment probes that only make sense on the target
206// machine: port availability for the embedded listener and root existence.
207func (c Config) CheckHost() error {
208 var errs []error
209
210 if st, err := os.Stat(c.Server.Root); err != nil {
211 errs = append(errs, fmt.Errorf("server.root: %w", err))
212 } else if !st.IsDir() {
213 errs = append(errs, fmt.Errorf("server.root %q is not a directory", c.Server.Root))
214 }
215
216 if c.SSH.Mode == "embedded" {
217 addr := net.JoinHostPort("", strconv.Itoa(c.SSH.Port))
218 ln, err := net.Listen("tcp", addr)
219 if err != nil {
220 errs = append(errs, fmt.Errorf("ssh.port %d is not bindable (already in use by another daemon?): %w", c.SSH.Port, err))
221 } else {
222 ln.Close()
223 }
224 }
225
226 return errors.Join(errs...)
227}