lego/acme/tls_sni_challenge.go
Tommie Gannert 58a2fd2267 Split off validation function.
This is a loop that interacts with the ACME server, not the individual challenges.

Also switch to exponential back-off polling for good measure.
2015-12-05 11:52:24 +00:00

108 lines
2.4 KiB
Go

package acme
import (
"crypto/rsa"
"crypto/sha256"
"crypto/tls"
"encoding/hex"
"fmt"
"net"
"net/http"
)
type tlsSNIChallenge struct {
jws *jws
optPort string
start chan net.Listener
end chan error
}
func (t *tlsSNIChallenge) Solve(chlng challenge, domain string) error {
// FIXME: https://github.com/ietf-wg-acme/acme/pull/22
// Currently we implement this challenge to track boulder, not the current spec!
logf("[INFO] acme: Trying to solve TLS-SNI-01")
t.start = make(chan net.Listener)
t.end = make(chan error)
// Generate the Key Authorization for the challenge
keyAuth, err := getKeyAuthorization(chlng.Token, &t.jws.privKey.PublicKey)
if err != nil {
return err
}
certificate, err := t.generateCertificate(keyAuth)
if err != nil {
return err
}
go t.startSNITLSServer(certificate)
var listener net.Listener
select {
case listener = <-t.start:
break
case err := <-t.end:
return fmt.Errorf("Could not start HTTPS server for challenge -> %v", err)
}
// Make sure we properly close the HTTP server before we return
defer func() {
listener.Close()
err = <-t.end
close(t.start)
close(t.end)
}()
return validate(t.jws, chlng.URI, challenge{Resource: "challenge", Type: chlng.Type, Token: chlng.Token, KeyAuthorization: keyAuth})
}
func (t *tlsSNIChallenge) generateCertificate(keyAuth string) (tls.Certificate, error) {
zBytes := sha256.Sum256([]byte(keyAuth))
z := hex.EncodeToString(zBytes[:sha256.Size])
// generate a new RSA key for the certificates
tempPrivKey, err := generatePrivateKey(rsakey, 2048)
if err != nil {
return tls.Certificate{}, err
}
rsaPrivKey := tempPrivKey.(*rsa.PrivateKey)
rsaPrivPEM := pemEncode(rsaPrivKey)
domain := fmt.Sprintf("%s.%s.acme.invalid", z[:32], z[32:])
tempCertPEM, err := generatePemCert(rsaPrivKey, domain)
if err != nil {
return tls.Certificate{}, err
}
certificate, err := tls.X509KeyPair(tempCertPEM, rsaPrivPEM)
if err != nil {
return tls.Certificate{}, err
}
return certificate, nil
}
func (t *tlsSNIChallenge) startSNITLSServer(cert tls.Certificate) {
// Allow for CLI port override
port := ":443"
if t.optPort != "" {
port = ":" + t.optPort
}
tlsConf := new(tls.Config)
tlsConf.Certificates = []tls.Certificate{cert}
tlsListener, err := tls.Listen("tcp", port, tlsConf)
if err != nil {
t.end <- err
}
// Signal successfull start
t.start <- tlsListener
http.Serve(tlsListener, nil)
t.end <- nil
}