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|
package config
import (
"flag"
"fmt"
"github.com/BurntSushi/toml"
)
type Config struct {
Server ServerConfig `toml:"server"`
Cache CacheConfig `toml:"cache"`
Resolver ResolverConfig `toml:"resolver"`
Blocklist BlocklistConfig `toml:"blocklist"`
Admin AdminConfig `toml:"admin"`
ACL ACLConfig `toml:"acl"`
Log LogConfig `toml:"log"`
}
type ServerConfig struct {
ListenUDP string `toml:"listen_udp"`
ListenTCP string `toml:"listen_tcp"`
ListenDOH string `toml:"listen_doh"`
}
type CacheConfig struct {
MaxEntries int `toml:"max_entries"`
DBPath string `toml:"db_path"`
}
type ResolverConfig struct {
Mode string `toml:"mode"`
Timeout string `toml:"timeout"`
MaxDelegations int `toml:"max_delegations"`
Forwarders []string `toml:"forwarders"`
}
type BlocklistConfig struct {
Response string `toml:"response"`
Files []string `toml:"files"`
URLs []string `toml:"urls"`
}
type LogConfig struct {
Level string `toml:"level"`
}
type CLIFlags struct {
Config string
LogLevel string
ListenUDP string
ListenTCP string
ListenDOH string
}
type ACLConfig struct {
Allow []string `toml:"allow"`
RateLimitQPS int `toml:"rate_limit_qps"`
RateLimitBurst int `toml:"rate_limit_burst"`
}
type AdminConfig struct {
Listen string `toml:"listen"`
}
func ParseFlags() CLIFlags {
var f CLIFlags
flag.StringVar(&f.Config, "config", "linum.toml", "path to config file")
flag.StringVar(&f.LogLevel, "loglevel", "", "log level (debug|info|warn|error)")
flag.StringVar(&f.ListenUDP, "udp", "", "UDP listen address")
flag.StringVar(&f.ListenTCP, "tcp", "", "TCP listen address")
flag.StringVar(&f.ListenDOH, "doh", "", "DoH listen address")
flag.Parse()
return f
}
func Default() Config {
return Config{
Server: ServerConfig{
ListenUDP: ":5353",
ListenTCP: ":5353",
ListenDOH: ":8443",
},
Cache: CacheConfig{
MaxEntries: 100000,
},
Resolver: ResolverConfig{
Mode: "recursive",
Timeout: "2s",
MaxDelegations: 30,
},
Blocklist: BlocklistConfig{
Response: "zero_ip",
},
Log: LogConfig{
Level: "info",
},
Admin: AdminConfig{
Listen: "127.0.0.1:8080",
},
ACL: ACLConfig{
Allow: []string{},
RateLimitQPS: 50,
RateLimitBurst: 10,
},
}
}
func LoadFile(path string) (Config, error) {
var cfg Config
_, err := toml.DecodeFile(path, &cfg)
return cfg, err
}
func Merge(dst, src Config) Config {
if src.Server.ListenUDP != "" {
dst.Server.ListenUDP = src.Server.ListenUDP
}
if src.Server.ListenTCP != "" {
dst.Server.ListenTCP = src.Server.ListenTCP
}
if src.Server.ListenDOH != "" {
dst.Server.ListenDOH = src.Server.ListenDOH
}
if src.Cache.MaxEntries > 0 {
dst.Cache.MaxEntries = src.Cache.MaxEntries
}
if src.Cache.DBPath != "" {
dst.Cache.DBPath = src.Cache.DBPath
}
if src.Resolver.Timeout != "" {
dst.Resolver.Timeout = src.Resolver.Timeout
}
if src.Resolver.MaxDelegations > 0 {
dst.Resolver.MaxDelegations = src.Resolver.MaxDelegations
}
if src.Resolver.Mode != "" {
dst.Resolver.Mode = src.Resolver.Mode
}
if len(src.Resolver.Forwarders) > 0 {
dst.Resolver.Forwarders = src.Resolver.Forwarders
}
if src.Blocklist.Response != "" {
dst.Blocklist.Response = src.Blocklist.Response
}
if len(src.Blocklist.Files) > 0 {
dst.Blocklist.Files = src.Blocklist.Files
}
if len(src.Blocklist.URLs) > 0 {
dst.Blocklist.URLs = src.Blocklist.URLs
}
if src.Log.Level != "" {
dst.Log.Level = src.Log.Level
}
if src.ACL.Allow != nil {
dst.ACL.Allow = src.ACL.Allow
}
if src.ACL.RateLimitQPS != 0 {
dst.ACL.RateLimitQPS = src.ACL.RateLimitQPS
}
if src.ACL.RateLimitBurst != 0 {
dst.ACL.RateLimitBurst = src.ACL.RateLimitBurst
}
if src.Admin.Listen != "" {
dst.Admin.Listen = src.Admin.Listen
}
return dst
}
func (f CLIFlags) Apply(cfg Config) Config {
if f.ListenUDP != "" {
cfg.Server.ListenUDP = f.ListenUDP
}
if f.ListenTCP != "" {
cfg.Server.ListenTCP = f.ListenTCP
}
if f.ListenDOH != "" {
cfg.Server.ListenDOH = f.ListenDOH
}
if f.LogLevel != "" {
cfg.Log.Level = f.LogLevel
}
return cfg
}
func (c Config) Validate() error {
switch c.Blocklist.Response {
case "zero_ip", "nxdomain", "":
default:
return fmt.Errorf("invalid blocklist response %q (want zero_ip or nxdomain)", c.Blocklist.Response)
}
switch c.ACL.Allow {
default:
}
switch c.Resolver.Mode {
case "recursive", "forward", "":
// nothing happened lol
default:
return fmt.Errorf("invalid resolver mode %q (recursive or forward)", c.Resolver.Mode)
}
if c.Resolver.Mode == "forward" && len(c.Resolver.Forwarders) == 0 {
return fmt.Errorf("resolver mode=forward requires at least one forwarder")
}
return nil
}
|
