astraproxy/main.go

184 lines
5.0 KiB
Go

package main
import (
"crypto/tls"
"flag"
"fmt"
"log"
"net/http"
"os"
"path/filepath"
"strings"
"time"
"golang.org/x/crypto/acme"
"golang.org/x/crypto/acme/autocert"
)
var (
home, _ = os.UserHomeDir()
version = "undefined"
)
func perror(msg string) {
fmt.Fprintln(os.Stderr, "")
fmt.Fprintln(os.Stderr, msg)
}
func arg_fail(msg string) {
perror(msg)
perror("Usage:")
flag.PrintDefaults()
os.Exit(2)
}
type CSVArg []string
func (a *CSVArg) Set(s string) error {
*a = strings.Split(s, ",")
return nil
}
func (a *CSVArg) String() string {
if a == nil {
return "<nil>"
}
if *a == nil {
return "<empty>"
}
return strings.Join(*a, ",")
}
type CLIArgs struct {
bind_address string
auth string
verbosity int
timeout time.Duration
cert, key, cafile string
list_ciphers bool
ciphers string
disableHTTP2 bool
showVersion bool
autocert bool
autocertWhitelist CSVArg
autocertDir string
autocertACME string
autocertEmail string
autocertHTTP string
}
func list_ciphers() {
for _, cipher := range tls.CipherSuites() {
fmt.Println(cipher.Name)
}
}
func parse_args() CLIArgs {
var args CLIArgs
flag.StringVar(&args.bind_address, "bind-address", ":8080", "HTTP proxy listen address")
flag.StringVar(&args.auth, "auth", "none://", "auth parameters")
flag.IntVar(&args.verbosity, "verbosity", 20, "logging verbosity "+
"(10 - debug, 20 - info, 30 - warning, 40 - error, 50 - critical)")
flag.DurationVar(&args.timeout, "timeout", 10*time.Second, "timeout for network operations")
flag.StringVar(&args.cert, "cert", "", "enable TLS and use certificate")
flag.StringVar(&args.key, "key", "", "key for TLS certificate")
flag.StringVar(&args.cafile, "cafile", "", "CA file to authenticate clients with certificates")
flag.BoolVar(&args.list_ciphers, "list-ciphers", false, "list ciphersuites")
flag.StringVar(&args.ciphers, "ciphers", "", "colon-separated list of enabled ciphers")
flag.BoolVar(&args.disableHTTP2, "disable-http2", false, "disable HTTP2")
flag.BoolVar(&args.showVersion, "version", false, "show program version and exit")
flag.BoolVar(&args.autocert, "autocert", false, "issue TLS certificates automatically")
flag.Var(&args.autocertWhitelist, "autocert-whitelist", "restrict autocert domains to this comma-separated list")
flag.StringVar(&args.autocertDir, "autocert-dir", filepath.Join(home, ".dumbproxy", "autocert"), "path to autocert cache")
flag.StringVar(&args.autocertACME, "autocert-acme", autocert.DefaultACMEDirectory, "custom ACME endpoint")
flag.StringVar(&args.autocertEmail, "autocert-email", "", "email used for ACME registration")
flag.StringVar(&args.autocertHTTP, "autocert-http", "", "listen address for HTTP-01 challenges handler of ACME")
flag.Parse()
return args
}
func run() int {
args := parse_args()
if args.showVersion {
fmt.Println(version)
return 0
}
if args.list_ciphers {
list_ciphers()
return 0
}
logWriter := NewLogWriter(os.Stderr)
defer logWriter.Close()
mainLogger := NewCondLogger(log.New(logWriter, "MAIN : ",
log.LstdFlags|log.Lshortfile),
args.verbosity)
proxyLogger := NewCondLogger(log.New(logWriter, "PROXY : ",
log.LstdFlags|log.Lshortfile),
args.verbosity)
auth, err := NewAuth(args.auth)
if err != nil {
mainLogger.Critical("Failed to instantiate auth provider: %v", err)
return 3
}
server := http.Server{
Addr: args.bind_address,
Handler: NewProxyHandler(args.timeout, auth, proxyLogger),
ErrorLog: log.New(logWriter, "HTTPSRV : ", log.LstdFlags|log.Lshortfile),
ReadTimeout: 0,
ReadHeaderTimeout: 0,
WriteTimeout: 0,
IdleTimeout: 0,
}
if args.disableHTTP2 {
server.TLSNextProto = make(map[string]func(*http.Server, *tls.Conn, http.Handler))
}
mainLogger.Info("Starting proxy server...")
if args.cert != "" {
cfg, err1 := makeServerTLSConfig(args.cert, args.key, args.cafile)
if err1 != nil {
mainLogger.Critical("TLS config construction failed: %v", err1)
return 3
}
cfg.CipherSuites = makeCipherList(args.ciphers)
server.TLSConfig = cfg
err = server.ListenAndServeTLS("", "")
} else if args.autocert {
m := &autocert.Manager{
Cache: autocert.DirCache(args.autocertDir),
Prompt: autocert.AcceptTOS,
Client: &acme.Client{DirectoryURL: args.autocertACME},
Email: args.autocertEmail,
}
if args.autocertWhitelist != nil {
m.HostPolicy = autocert.HostWhitelist([]string(args.autocertWhitelist)...)
}
if args.autocertHTTP != "" {
go func() {
log.Fatalf("HTTP-01 ACME challenge server stopped: %v",
http.ListenAndServe(args.autocertHTTP, m.HTTPHandler(nil)))
}()
}
cfg := m.TLSConfig()
cfg.CipherSuites = makeCipherList(args.ciphers)
server.TLSConfig = cfg
err = server.ListenAndServeTLS("", "")
} else {
err = server.ListenAndServe()
}
mainLogger.Critical("Server terminated with a reason: %v", err)
mainLogger.Info("Shutting down...")
return 0
}
func main() {
os.Exit(run())
}