94 lines
2.5 KiB
Go
94 lines
2.5 KiB
Go
package main
|
|
|
|
import (
|
|
"bytes"
|
|
"context"
|
|
"crypto/md5"
|
|
"crypto/tls"
|
|
"crypto/x509"
|
|
"encoding/hex"
|
|
"fmt"
|
|
"log"
|
|
"os"
|
|
"strings"
|
|
|
|
"tildegit.org/tjp/gus"
|
|
guslog "tildegit.org/tjp/gus/contrib/log"
|
|
"tildegit.org/tjp/gus/gemini"
|
|
)
|
|
|
|
func main() {
|
|
// Get TLS files from the environment
|
|
certfile, keyfile := envConfig()
|
|
|
|
// build a TLS configuration suitable for gemini
|
|
tlsconf, err := gemini.FileTLS(certfile, keyfile)
|
|
if err != nil {
|
|
log.Fatal(err)
|
|
}
|
|
|
|
// add stdout logging to the request handler
|
|
handler := guslog.Requests(os.Stdout, nil)(inspectHandler)
|
|
|
|
// run the server
|
|
server, err := gemini.NewServer(context.Background(), tlsconf, "tcp4", ":1965", handler)
|
|
if err != nil {
|
|
log.Fatal(err)
|
|
}
|
|
server.Serve()
|
|
}
|
|
|
|
func envConfig() (string, string) {
|
|
certfile, ok := os.LookupEnv("SERVER_CERTIFICATE")
|
|
if !ok {
|
|
log.Fatal("missing SERVER_CERTIFICATE environment variable")
|
|
}
|
|
|
|
keyfile, ok := os.LookupEnv("SERVER_PRIVATEKEY")
|
|
if !ok {
|
|
log.Fatal("missing SERVER_PRIVATEKEY environment variable")
|
|
}
|
|
|
|
return certfile, keyfile
|
|
}
|
|
|
|
func inspectHandler(ctx context.Context, req *gus.Request) *gus.Response {
|
|
// build and return a ```-wrapped description of the connection TLS state
|
|
body := "```\n" + displayTLSState(req.TLSState) + "\n```"
|
|
return gemini.Success("text/gemini", bytes.NewBufferString(body))
|
|
}
|
|
|
|
func displayTLSState(state *tls.ConnectionState) string {
|
|
builder := &strings.Builder{}
|
|
|
|
builder.WriteString("Version: ")
|
|
builder.WriteString(map[uint16]string{
|
|
tls.VersionTLS10: "TLSv1.0",
|
|
tls.VersionTLS11: "TLSv1.1",
|
|
tls.VersionTLS12: "TLSv1.2",
|
|
tls.VersionTLS13: "TLSv1.3",
|
|
tls.VersionSSL30: "SSLv3",
|
|
}[state.Version])
|
|
builder.WriteString("\n")
|
|
|
|
builder.WriteString(fmt.Sprintf("Handshake complete: %t\n", state.HandshakeComplete))
|
|
builder.WriteString(fmt.Sprintf("Did resume: %t\n", state.DidResume))
|
|
builder.WriteString(fmt.Sprintf("Cipher suite: %x\n", state.CipherSuite))
|
|
builder.WriteString(fmt.Sprintf("Negotiated protocol: %q\n", state.NegotiatedProtocol))
|
|
builder.WriteString(fmt.Sprintf("Server name: %s\n", state.ServerName))
|
|
|
|
builder.WriteString(fmt.Sprintf("Certificates (%d)\n", len(state.PeerCertificates)))
|
|
for i, cert := range state.PeerCertificates {
|
|
builder.WriteString(fmt.Sprintf(" #%d: %s\n", i+1, fingerprint(cert)))
|
|
}
|
|
|
|
return builder.String()
|
|
}
|
|
|
|
func fingerprint(cert *x509.Certificate) []byte {
|
|
raw := md5.Sum(cert.Raw)
|
|
dst := make([]byte, hex.EncodedLen(len(raw)))
|
|
hex.Encode(dst, raw[:])
|
|
return dst
|
|
}
|