headscale/hscontrol/types/config.go

671 lines
19 KiB
Go

package types
import (
"errors"
"fmt"
"io/fs"
"net/netip"
"net/url"
"os"
"strings"
"time"
"github.com/coreos/go-oidc/v3/oidc"
"github.com/juanfont/headscale/hscontrol/util"
"github.com/prometheus/common/model"
"github.com/rs/zerolog"
"github.com/rs/zerolog/log"
"github.com/spf13/viper"
"go4.org/netipx"
"tailscale.com/net/tsaddr"
"tailscale.com/tailcfg"
"tailscale.com/types/dnstype"
)
const (
defaultOIDCExpiryTime = 180 * 24 * time.Hour // 180 Days
maxDuration time.Duration = 1<<63 - 1
)
var errOidcMutuallyExclusive = errors.New(
"oidc_client_secret and oidc_client_secret_path are mutually exclusive",
)
// Config contains the initial Headscale configuration.
type Config struct {
ServerURL string
Addr string
MetricsAddr string
GRPCAddr string
GRPCAllowInsecure bool
EphemeralNodeInactivityTimeout time.Duration
NodeUpdateCheckInterval time.Duration
IPPrefixes []netip.Prefix
NoisePrivateKeyPath string
BaseDomain string
Log LogConfig
DisableUpdateCheck bool
DERP DERPConfig
DBtype string
DBpath string
DBhost string
DBport int
DBname string
DBuser string
DBpass string
DBssl string
TLS TLSConfig
ACMEURL string
ACMEEmail string
DNSConfig *tailcfg.DNSConfig
UnixSocket string
UnixSocketPermission fs.FileMode
OIDC OIDCConfig
LogTail LogTailConfig
RandomizeClientPort bool
CLI CLIConfig
ACL ACLConfig
}
type TLSConfig struct {
CertPath string
KeyPath string
LetsEncrypt LetsEncryptConfig
}
type LetsEncryptConfig struct {
Listen string
Hostname string
CacheDir string
ChallengeType string
}
type OIDCConfig struct {
OnlyStartIfOIDCIsAvailable bool
Issuer string
ClientID string
ClientSecret string
Scope []string
ExtraParams map[string]string
AllowedDomains []string
AllowedUsers []string
AllowedGroups []string
StripEmaildomain bool
Expiry time.Duration
UseExpiryFromToken bool
}
type DERPConfig struct {
ServerEnabled bool
ServerRegionID int
ServerRegionCode string
ServerRegionName string
ServerPrivateKeyPath string
STUNAddr string
URLs []url.URL
Paths []string
AutoUpdate bool
UpdateFrequency time.Duration
}
type LogTailConfig struct {
Enabled bool
}
type CLIConfig struct {
Address string
APIKey string
Timeout time.Duration
Insecure bool
}
type ACLConfig struct {
PolicyPath string
}
type LogConfig struct {
Format string
Level zerolog.Level
}
func LoadConfig(path string, isFile bool) error {
if isFile {
viper.SetConfigFile(path)
} else {
viper.SetConfigName("config")
if path == "" {
viper.AddConfigPath("/etc/headscale/")
viper.AddConfigPath("$HOME/.headscale")
viper.AddConfigPath(".")
} else {
// For testing
viper.AddConfigPath(path)
}
}
viper.SetEnvPrefix("headscale")
viper.SetEnvKeyReplacer(strings.NewReplacer(".", "_"))
viper.AutomaticEnv()
viper.SetDefault("tls_letsencrypt_cache_dir", "/var/www/.cache")
viper.SetDefault("tls_letsencrypt_challenge_type", HTTP01ChallengeType)
viper.SetDefault("log.level", "info")
viper.SetDefault("log.format", TextLogFormat)
viper.SetDefault("dns_config", nil)
viper.SetDefault("dns_config.override_local_dns", true)
viper.SetDefault("derp.server.enabled", false)
viper.SetDefault("derp.server.stun.enabled", true)
viper.SetDefault("unix_socket", "/var/run/headscale/headscale.sock")
viper.SetDefault("unix_socket_permission", "0o770")
viper.SetDefault("grpc_listen_addr", ":50443")
viper.SetDefault("grpc_allow_insecure", false)
viper.SetDefault("cli.timeout", "5s")
viper.SetDefault("cli.insecure", false)
viper.SetDefault("db_ssl", false)
viper.SetDefault("oidc.scope", []string{oidc.ScopeOpenID, "profile", "email"})
viper.SetDefault("oidc.strip_email_domain", true)
viper.SetDefault("oidc.only_start_if_oidc_is_available", true)
viper.SetDefault("oidc.expiry", "180d")
viper.SetDefault("oidc.use_expiry_from_token", false)
viper.SetDefault("logtail.enabled", false)
viper.SetDefault("randomize_client_port", false)
viper.SetDefault("ephemeral_node_inactivity_timeout", "120s")
viper.SetDefault("node_update_check_interval", "10s")
if IsCLIConfigured() {
return nil
}
if err := viper.ReadInConfig(); err != nil {
log.Warn().Err(err).Msg("Failed to read configuration from disk")
return fmt.Errorf("fatal error reading config file: %w", err)
}
// Collect any validation errors and return them all at once
var errorText string
if (viper.GetString("tls_letsencrypt_hostname") != "") &&
((viper.GetString("tls_cert_path") != "") || (viper.GetString("tls_key_path") != "")) {
errorText += "Fatal config error: set either tls_letsencrypt_hostname or tls_cert_path/tls_key_path, not both\n"
}
if !viper.IsSet("noise") || viper.GetString("noise.private_key_path") == "" {
errorText += "Fatal config error: headscale now requires a new `noise.private_key_path` field in the config file for the Tailscale v2 protocol\n"
}
if (viper.GetString("tls_letsencrypt_hostname") != "") &&
(viper.GetString("tls_letsencrypt_challenge_type") == TLSALPN01ChallengeType) &&
(!strings.HasSuffix(viper.GetString("listen_addr"), ":443")) {
// this is only a warning because there could be something sitting in front of headscale that redirects the traffic (e.g. an iptables rule)
log.Warn().
Msg("Warning: when using tls_letsencrypt_hostname with TLS-ALPN-01 as challenge type, headscale must be reachable on port 443, i.e. listen_addr should probably end in :443")
}
if (viper.GetString("tls_letsencrypt_challenge_type") != HTTP01ChallengeType) &&
(viper.GetString("tls_letsencrypt_challenge_type") != TLSALPN01ChallengeType) {
errorText += "Fatal config error: the only supported values for tls_letsencrypt_challenge_type are HTTP-01 and TLS-ALPN-01\n"
}
if !strings.HasPrefix(viper.GetString("server_url"), "http://") &&
!strings.HasPrefix(viper.GetString("server_url"), "https://") {
errorText += "Fatal config error: server_url must start with https:// or http://\n"
}
// Minimum inactivity time out is keepalive timeout (60s) plus a few seconds
// to avoid races
minInactivityTimeout, _ := time.ParseDuration("65s")
if viper.GetDuration("ephemeral_node_inactivity_timeout") <= minInactivityTimeout {
errorText += fmt.Sprintf(
"Fatal config error: ephemeral_node_inactivity_timeout (%s) is set too low, must be more than %s",
viper.GetString("ephemeral_node_inactivity_timeout"),
minInactivityTimeout,
)
}
maxNodeUpdateCheckInterval, _ := time.ParseDuration("60s")
if viper.GetDuration("node_update_check_interval") > maxNodeUpdateCheckInterval {
errorText += fmt.Sprintf(
"Fatal config error: node_update_check_interval (%s) is set too high, must be less than %s",
viper.GetString("node_update_check_interval"),
maxNodeUpdateCheckInterval,
)
}
if errorText != "" {
//nolint
return errors.New(strings.TrimSuffix(errorText, "\n"))
} else {
return nil
}
}
func GetTLSConfig() TLSConfig {
return TLSConfig{
LetsEncrypt: LetsEncryptConfig{
Hostname: viper.GetString("tls_letsencrypt_hostname"),
Listen: viper.GetString("tls_letsencrypt_listen"),
CacheDir: util.AbsolutePathFromConfigPath(
viper.GetString("tls_letsencrypt_cache_dir"),
),
ChallengeType: viper.GetString("tls_letsencrypt_challenge_type"),
},
CertPath: util.AbsolutePathFromConfigPath(
viper.GetString("tls_cert_path"),
),
KeyPath: util.AbsolutePathFromConfigPath(
viper.GetString("tls_key_path"),
),
}
}
func GetDERPConfig() DERPConfig {
serverEnabled := viper.GetBool("derp.server.enabled")
serverRegionID := viper.GetInt("derp.server.region_id")
serverRegionCode := viper.GetString("derp.server.region_code")
serverRegionName := viper.GetString("derp.server.region_name")
stunAddr := viper.GetString("derp.server.stun_listen_addr")
privateKeyPath := util.AbsolutePathFromConfigPath(viper.GetString("derp.server.private_key_path"))
if serverEnabled && stunAddr == "" {
log.Fatal().
Msg("derp.server.stun_listen_addr must be set if derp.server.enabled is true")
}
urlStrs := viper.GetStringSlice("derp.urls")
urls := make([]url.URL, len(urlStrs))
for index, urlStr := range urlStrs {
urlAddr, err := url.Parse(urlStr)
if err != nil {
log.Error().
Str("url", urlStr).
Err(err).
Msg("Failed to parse url, ignoring...")
}
urls[index] = *urlAddr
}
paths := viper.GetStringSlice("derp.paths")
autoUpdate := viper.GetBool("derp.auto_update_enabled")
updateFrequency := viper.GetDuration("derp.update_frequency")
return DERPConfig{
ServerEnabled: serverEnabled,
ServerRegionID: serverRegionID,
ServerRegionCode: serverRegionCode,
ServerRegionName: serverRegionName,
ServerPrivateKeyPath: privateKeyPath,
STUNAddr: stunAddr,
URLs: urls,
Paths: paths,
AutoUpdate: autoUpdate,
UpdateFrequency: updateFrequency,
}
}
func GetLogTailConfig() LogTailConfig {
enabled := viper.GetBool("logtail.enabled")
return LogTailConfig{
Enabled: enabled,
}
}
func GetACLConfig() ACLConfig {
policyPath := viper.GetString("acl_policy_path")
return ACLConfig{
PolicyPath: policyPath,
}
}
func GetLogConfig() LogConfig {
logLevelStr := viper.GetString("log.level")
logLevel, err := zerolog.ParseLevel(logLevelStr)
if err != nil {
logLevel = zerolog.DebugLevel
}
logFormatOpt := viper.GetString("log.format")
var logFormat string
switch logFormatOpt {
case "json":
logFormat = JSONLogFormat
case "text":
logFormat = TextLogFormat
case "":
logFormat = TextLogFormat
default:
log.Error().
Str("func", "GetLogConfig").
Msgf("Could not parse log format: %s. Valid choices are 'json' or 'text'", logFormatOpt)
}
return LogConfig{
Format: logFormat,
Level: logLevel,
}
}
func GetDNSConfig() (*tailcfg.DNSConfig, string) {
if viper.IsSet("dns_config") {
dnsConfig := &tailcfg.DNSConfig{}
overrideLocalDNS := viper.GetBool("dns_config.override_local_dns")
if viper.IsSet("dns_config.nameservers") {
nameserversStr := viper.GetStringSlice("dns_config.nameservers")
nameservers := []netip.Addr{}
resolvers := []*dnstype.Resolver{}
for _, nameserverStr := range nameserversStr {
// Search for explicit DNS-over-HTTPS resolvers
if strings.HasPrefix(nameserverStr, "https://") {
resolvers = append(resolvers, &dnstype.Resolver{
Addr: nameserverStr,
})
// This nameserver can not be parsed as an IP address
continue
}
// Parse nameserver as a regular IP
nameserver, err := netip.ParseAddr(nameserverStr)
if err != nil {
log.Error().
Str("func", "getDNSConfig").
Err(err).
Msgf("Could not parse nameserver IP: %s", nameserverStr)
}
nameservers = append(nameservers, nameserver)
resolvers = append(resolvers, &dnstype.Resolver{
Addr: nameserver.String(),
})
}
dnsConfig.Nameservers = nameservers
if overrideLocalDNS {
dnsConfig.Resolvers = resolvers
} else {
dnsConfig.FallbackResolvers = resolvers
}
}
if viper.IsSet("dns_config.restricted_nameservers") {
dnsConfig.Routes = make(map[string][]*dnstype.Resolver)
domains := []string{}
restrictedDNS := viper.GetStringMapStringSlice(
"dns_config.restricted_nameservers",
)
for domain, restrictedNameservers := range restrictedDNS {
restrictedResolvers := make(
[]*dnstype.Resolver,
len(restrictedNameservers),
)
for index, nameserverStr := range restrictedNameservers {
nameserver, err := netip.ParseAddr(nameserverStr)
if err != nil {
log.Error().
Str("func", "getDNSConfig").
Err(err).
Msgf("Could not parse restricted nameserver IP: %s", nameserverStr)
}
restrictedResolvers[index] = &dnstype.Resolver{
Addr: nameserver.String(),
}
}
dnsConfig.Routes[domain] = restrictedResolvers
domains = append(domains, domain)
}
dnsConfig.Domains = domains
}
if viper.IsSet("dns_config.domains") {
domains := viper.GetStringSlice("dns_config.domains")
if len(dnsConfig.Resolvers) > 0 {
dnsConfig.Domains = domains
} else if domains != nil {
log.Warn().
Msg("Warning: dns_config.domains is set, but no nameservers are configured. Ignoring domains.")
}
}
if viper.IsSet("dns_config.extra_records") {
var extraRecords []tailcfg.DNSRecord
err := viper.UnmarshalKey("dns_config.extra_records", &extraRecords)
if err != nil {
log.Error().
Str("func", "getDNSConfig").
Err(err).
Msgf("Could not parse dns_config.extra_records")
}
dnsConfig.ExtraRecords = extraRecords
}
if viper.IsSet("dns_config.magic_dns") {
dnsConfig.Proxied = viper.GetBool("dns_config.magic_dns")
}
var baseDomain string
if viper.IsSet("dns_config.base_domain") {
baseDomain = viper.GetString("dns_config.base_domain")
} else {
baseDomain = "headscale.net" // does not really matter when MagicDNS is not enabled
}
log.Trace().Interface("dns_config", dnsConfig).Msg("DNS configuration loaded")
return dnsConfig, baseDomain
}
return nil, ""
}
func GetHeadscaleConfig() (*Config, error) {
if IsCLIConfigured() {
return &Config{
CLI: CLIConfig{
Address: viper.GetString("cli.address"),
APIKey: viper.GetString("cli.api_key"),
Timeout: viper.GetDuration("cli.timeout"),
Insecure: viper.GetBool("cli.insecure"),
},
}, nil
}
dnsConfig, baseDomain := GetDNSConfig()
derpConfig := GetDERPConfig()
logConfig := GetLogTailConfig()
randomizeClientPort := viper.GetBool("randomize_client_port")
configuredPrefixes := viper.GetStringSlice("ip_prefixes")
parsedPrefixes := make([]netip.Prefix, 0, len(configuredPrefixes)+1)
for i, prefixInConfig := range configuredPrefixes {
prefix, err := netip.ParsePrefix(prefixInConfig)
if err != nil {
panic(fmt.Errorf("failed to parse ip_prefixes[%d]: %w", i, err))
}
if prefix.Addr().Is4() {
builder := netipx.IPSetBuilder{}
builder.AddPrefix(tsaddr.CGNATRange())
ipSet, _ := builder.IPSet()
if !ipSet.ContainsPrefix(prefix) {
log.Warn().
Msgf("Prefix %s is not in the %s range. This is an unsupported configuration.",
prefixInConfig, tsaddr.CGNATRange())
}
}
if prefix.Addr().Is6() {
builder := netipx.IPSetBuilder{}
builder.AddPrefix(tsaddr.TailscaleULARange())
ipSet, _ := builder.IPSet()
if !ipSet.ContainsPrefix(prefix) {
log.Warn().
Msgf("Prefix %s is not in the %s range. This is an unsupported configuration.",
prefixInConfig, tsaddr.TailscaleULARange())
}
}
parsedPrefixes = append(parsedPrefixes, prefix)
}
prefixes := make([]netip.Prefix, 0, len(parsedPrefixes))
{
// dedup
normalizedPrefixes := make(map[string]int, len(parsedPrefixes))
for i, p := range parsedPrefixes {
normalized, _ := netipx.RangeOfPrefix(p).Prefix()
normalizedPrefixes[normalized.String()] = i
}
// convert back to list
for _, i := range normalizedPrefixes {
prefixes = append(prefixes, parsedPrefixes[i])
}
}
if len(prefixes) < 1 {
prefixes = append(prefixes, netip.MustParsePrefix("100.64.0.0/10"))
log.Warn().
Msgf("'ip_prefixes' not configured, falling back to default: %v", prefixes)
}
oidcClientSecret := viper.GetString("oidc.client_secret")
oidcClientSecretPath := viper.GetString("oidc.client_secret_path")
if oidcClientSecretPath != "" && oidcClientSecret != "" {
return nil, errOidcMutuallyExclusive
}
if oidcClientSecretPath != "" {
secretBytes, err := os.ReadFile(os.ExpandEnv(oidcClientSecretPath))
if err != nil {
return nil, err
}
oidcClientSecret = string(secretBytes)
}
return &Config{
ServerURL: viper.GetString("server_url"),
Addr: viper.GetString("listen_addr"),
MetricsAddr: viper.GetString("metrics_listen_addr"),
GRPCAddr: viper.GetString("grpc_listen_addr"),
GRPCAllowInsecure: viper.GetBool("grpc_allow_insecure"),
DisableUpdateCheck: viper.GetBool("disable_check_updates"),
IPPrefixes: prefixes,
NoisePrivateKeyPath: util.AbsolutePathFromConfigPath(
viper.GetString("noise.private_key_path"),
),
BaseDomain: baseDomain,
DERP: derpConfig,
EphemeralNodeInactivityTimeout: viper.GetDuration(
"ephemeral_node_inactivity_timeout",
),
NodeUpdateCheckInterval: viper.GetDuration(
"node_update_check_interval",
),
DBtype: viper.GetString("db_type"),
DBpath: util.AbsolutePathFromConfigPath(viper.GetString("db_path")),
DBhost: viper.GetString("db_host"),
DBport: viper.GetInt("db_port"),
DBname: viper.GetString("db_name"),
DBuser: viper.GetString("db_user"),
DBpass: viper.GetString("db_pass"),
DBssl: viper.GetString("db_ssl"),
TLS: GetTLSConfig(),
DNSConfig: dnsConfig,
ACMEEmail: viper.GetString("acme_email"),
ACMEURL: viper.GetString("acme_url"),
UnixSocket: viper.GetString("unix_socket"),
UnixSocketPermission: util.GetFileMode("unix_socket_permission"),
OIDC: OIDCConfig{
OnlyStartIfOIDCIsAvailable: viper.GetBool(
"oidc.only_start_if_oidc_is_available",
),
Issuer: viper.GetString("oidc.issuer"),
ClientID: viper.GetString("oidc.client_id"),
ClientSecret: oidcClientSecret,
Scope: viper.GetStringSlice("oidc.scope"),
ExtraParams: viper.GetStringMapString("oidc.extra_params"),
AllowedDomains: viper.GetStringSlice("oidc.allowed_domains"),
AllowedUsers: viper.GetStringSlice("oidc.allowed_users"),
AllowedGroups: viper.GetStringSlice("oidc.allowed_groups"),
StripEmaildomain: viper.GetBool("oidc.strip_email_domain"),
Expiry: func() time.Duration {
// if set to 0, we assume no expiry
if value := viper.GetString("oidc.expiry"); value == "0" {
return maxDuration
} else {
expiry, err := model.ParseDuration(value)
if err != nil {
log.Warn().Msg("failed to parse oidc.expiry, defaulting back to 180 days")
return defaultOIDCExpiryTime
}
return time.Duration(expiry)
}
}(),
UseExpiryFromToken: viper.GetBool("oidc.use_expiry_from_token"),
},
LogTail: logConfig,
RandomizeClientPort: randomizeClientPort,
ACL: GetACLConfig(),
CLI: CLIConfig{
Address: viper.GetString("cli.address"),
APIKey: viper.GetString("cli.api_key"),
Timeout: viper.GetDuration("cli.timeout"),
Insecure: viper.GetBool("cli.insecure"),
},
Log: GetLogConfig(),
}, nil
}
func IsCLIConfigured() bool {
return viper.GetString("cli.address") != "" && viper.GetString("cli.api_key") != ""
}