Can issue and use SSL certs and serve sites

Code is a huge mess; much cleanup to follow.

config/config.go

 package config
 
 import (
-	"errors"
 	"fmt"
 	"io"
 	"log"
@@ -13,7 +12,6 @@ import (
 	"github.com/mholt/caddy/config/setup"
 	"github.com/mholt/caddy/middleware"
 	"github.com/mholt/caddy/server"
-	"github.com/xenolf/lego/acme"
 )
 
 const (
@@ -103,34 +101,13 @@ func Load(filename string, input io.Reader) (Group, error) {
 	// restore logging settings
 	log.SetFlags(flags)
 
-	// Initiate Let's Encrypt
-	leUser, err := NewLetsEncryptUser("example1@mail.com")
+	// secure all the things
+	err = initiateLetsEncrypt(configs)
 	if err != nil {
-		return Group{}, err
-	}
-	for _, cfg := range configs {
-		// TODO: && !IsLoopback()
-		if !cfg.TLS.Enabled && cfg.Port != "http" {
-			client := acme.NewClient("http://192.168.99.100:4000", &leUser, 2048, "5001")
-			reg, err := client.Register()
-			if err != nil {
-				return Group{}, errors.New("Error Registering: " + err.Error())
-			}
-			leUser.Registration = reg
-
-			err = client.AgreeToTos()
-			if err != nil {
-				return Group{}, errors.New("Error Agreeing to ToS: " + err.Error())
-			}
-
-			certs, err := client.ObtainCertificates([]string{"caddy.dev"})
-			if err != nil {
-				return Group{}, errors.New("Error Obtaining Certs: " + err.Error())
-			}
-		}
+		return nil, err
 	}
 
-	// Group by address/virtualhosts
+	// group by address/virtualhosts
 	return arrangeBindings(configs)
 }
 

config/letsencrypt.go

 package config
 
 import (
+	"bufio"
 	"crypto/rand"
 	"crypto/rsa"
+	"crypto/x509"
+	"encoding/json"
+	"encoding/pem"
 	"errors"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"strings"
 
+	"github.com/mholt/caddy/app"
+	"github.com/mholt/caddy/server"
 	"github.com/xenolf/lego/acme"
 )
 
-func NewLetsEncryptUser(email string) (LetsEncryptUser, error) {
+const rsaKeySize = 2048
+
+// initiateLetsEncrypt sets up TLS ... <TODO>
+func initiateLetsEncrypt(configs []server.Config) error {
+	// fill map of email address to server configs that use that email address for TLS.
+	// this will help us reduce roundtrips when getting the certs.
+	initMap := make(map[string][]*server.Config)
+	for i := 0; i < len(configs); i++ {
+		if configs[i].TLS.Certificate == "" && configs[i].TLS.Key == "" && configs[i].Port != "http" { // TODO: && !cfg.Host.IsLoopback()
+			leEmail := getEmail(configs[i])
+			if leEmail == "" {
+				return errors.New("cannot serve HTTPS without email address OR certificate and key")
+			}
+			initMap[leEmail] = append(initMap[leEmail], &configs[i])
+		}
+	}
+
+	for leEmail, serverConfigs := range initMap {
+		leUser, err := getLetsEncryptUser(leEmail)
+		if err != nil {
+			return err
+		}
+
+		client := acme.NewClient("http://192.168.99.100:4000", &leUser, rsaKeySize, "5001")
+
+		if leUser.Registration == nil {
+			reg, err := client.Register()
+			if err != nil {
+				return errors.New("registration error: " + err.Error())
+			}
+			leUser.Registration = reg
+
+			// TODO: we can just do the agreement once, when registering, right?
+			err = client.AgreeToTos()
+			if err != nil {
+				saveLetsEncryptUser(leUser) // TODO: Might as well try, right? Error check?
+				return errors.New("error agreeing to terms: " + err.Error())
+			}
+
+			err = saveLetsEncryptUser(leUser)
+			if err != nil {
+				return errors.New("could not save user: " + err.Error())
+			}
+		}
+
+		// collect all the hostnames
+		var hosts []string
+		for _, cfg := range serverConfigs {
+			hosts = append(hosts, cfg.Host)
+		}
+
+		// showtime: let's get free, trusted SSL certificates! yee-haw!
+		certificates, err := client.ObtainCertificates(hosts)
+		if err != nil {
+			return errors.New("error obtaining certs: " + err.Error())
+		}
+
+		// ... that's it. pain gone. save the certs, keys, and update server configs.
+		for _, cert := range certificates {
+			certFolder := filepath.Join(app.DataFolder(), "letsencrypt", "sites", cert.Domain)
+			os.MkdirAll(certFolder, 0700)
+			// Save cert
+			err = saveCertificate(cert.Certificate, filepath.Join(certFolder, cert.Domain+".crt"))
+			//err = ioutil.WriteFile(filepath.Join(certFolder, cert.Domain+".crt"), cert.Certificate, 0600)
+			if err != nil {
+				return err
+			}
+
+			// Save private key
+			//savePrivateKey(cert.PrivateKey, filepath.Join(certFolder, cert.Domain+".key"))
+			err = ioutil.WriteFile(filepath.Join(certFolder, cert.Domain+".key"), cert.PrivateKey, 0600)
+			if err != nil {
+				return err
+			}
+
+			// Save cert metadata
+			jsonBytes, err := json.MarshalIndent(&CertificateMeta{URL: cert.CertURL, Domain: cert.Domain}, "", "\t")
+			if err != nil {
+				return err
+			}
+			err = ioutil.WriteFile(filepath.Join(certFolder, cert.Domain+".json"), jsonBytes, 0600)
+			if err != nil {
+				return err
+			}
+		}
+
+		// it all comes down to this: filling in the file path of a valid certificate automatically
+		for _, cfg := range serverConfigs {
+			cfg.TLS.Certificate = filepath.Join(app.DataFolder(), "letsencrypt", "sites", cfg.Host, cfg.Host+".crt")
+			cfg.TLS.Key = filepath.Join(app.DataFolder(), "letsencrypt", "sites", cfg.Host, cfg.Host+".key")
+		}
+	}
+
+	return nil
+}
+
+func getEmail(cfg server.Config) string {
+	leEmail := cfg.TLS.LetsEncryptEmail
+	if leEmail == "" {
+		leEmail = LetsEncryptEmail
+	}
+	if leEmail == "" {
+		// TODO: get most recent email from ~/.caddy/users file
+	}
+	if leEmail == "" {
+		reader := bufio.NewReader(os.Stdin)
+		fmt.Print("Email address: ")
+		var err error
+		leEmail, err = reader.ReadString('\n')
+		if err != nil {
+			return ""
+		}
+		LetsEncryptEmail = leEmail
+	}
+	return strings.TrimSpace(leEmail)
+}
+
+func saveLetsEncryptUser(user LetsEncryptUser) error {
+	// make user account folder
+	userFolder := filepath.Join(app.DataFolder(), "letsencrypt", "users", user.Email)
+	err := os.MkdirAll(userFolder, 0700)
+	if err != nil {
+		return err
+	}
+
+	// save private key file
+	user.KeyFile = filepath.Join(userFolder, emailUsername(user.Email)+".key")
+	err = savePrivateKey(user.key, user.KeyFile)
+	if err != nil {
+		return err
+	}
+
+	// save registration file
+	jsonBytes, err := json.MarshalIndent(&user, "", "\t")
+	if err != nil {
+		return err
+	}
+
+	return ioutil.WriteFile(filepath.Join(userFolder, "registration.json"), jsonBytes, 0600)
+}
+
+func getLetsEncryptUser(email string) (LetsEncryptUser, error) {
+	var user LetsEncryptUser
+
+	userFolder := filepath.Join(app.DataFolder(), "letsencrypt", "users", email)
+	regFile, err := os.Open(filepath.Join(userFolder, "registration.json"))
+	if err != nil {
+		if os.IsNotExist(err) {
+			// create a new user
+			return newLetsEncryptUser(email)
+		}
+		return user, err
+	}
+
+	err = json.NewDecoder(regFile).Decode(&user)
+	if err != nil {
+		return user, err
+	}
+
+	user.key, err = loadPrivateKey(user.KeyFile)
+	if err != nil {
+		return user, err
+	}
+
+	return user, nil
+}
+
+func newLetsEncryptUser(email string) (LetsEncryptUser, error) {
 	user := LetsEncryptUser{Email: email}
-	privateKey, err := rsa.GenerateKey(rand.Reader, 2048)
+	privateKey, err := rsa.GenerateKey(rand.Reader, rsaKeySize)
 	if err != nil {
 		return user, errors.New("error generating private key: " + err.Error())
 	}
-	user.Key = privateKey
+	user.key = privateKey
 	return user, nil
 }
 
+func emailUsername(email string) string {
+	at := strings.Index(email, "@")
+	if at == -1 {
+		return email
+	}
+	return email[:at]
+}
+
 type LetsEncryptUser struct {
 	Email        string
 	Registration *acme.RegistrationResource
-	Key          *rsa.PrivateKey
+	KeyFile      string
+	key          *rsa.PrivateKey
 }
 
 func (u LetsEncryptUser) GetEmail() string {
@@ -31,5 +218,49 @@ func (u LetsEncryptUser) GetRegistration() *acme.RegistrationResource {
 	return u.Registration
 }
 func (u LetsEncryptUser) GetPrivateKey() *rsa.PrivateKey {
-	return u.Key
+	return u.key
+}
+
+// savePrivateKey saves an RSA private key to file.
+//
+// Borrowed from Sebastian Erhart
+// https://github.com/xenolf/lego/blob/34910bd541315993224af1f04f9b2877513e5477/crypto.go
+func savePrivateKey(key *rsa.PrivateKey, file string) error {
+	pemKey := pem.Block{Type: "RSA PRIVATE KEY", Bytes: x509.MarshalPKCS1PrivateKey(key)}
+	keyOut, err := os.Create(file)
+	if err != nil {
+		return err
+	}
+	pem.Encode(keyOut, &pemKey)
+	keyOut.Close()
+	return nil
+}
+
+// TODO: Check file permission
+func saveCertificate(certBytes []byte, file string) error {
+	pemCert := pem.Block{Type: "CERTIFICATE", Bytes: certBytes}
+	certOut, err := os.Create(file)
+	if err != nil {
+		return err
+	}
+	pem.Encode(certOut, &pemCert)
+	certOut.Close()
+	return nil
+}
+
+// loadPrivateKey loads an RSA private key from filename.
+//
+// Borrowed from Sebastian Erhart
+// https://github.com/xenolf/lego/blob/34910bd541315993224af1f04f9b2877513e5477/crypto.go
+func loadPrivateKey(file string) (*rsa.PrivateKey, error) {
+	keyBytes, err := ioutil.ReadFile(file)
+	if err != nil {
+		return nil, err
+	}
+	keyBlock, _ := pem.Decode(keyBytes)
+	return x509.ParsePKCS1PrivateKey(keyBlock.Bytes)
+}
+
+type CertificateMeta struct {
+	Domain, URL string
 }

config/setup/tls.go

@@ -11,10 +11,7 @@ import (
 func TLS(c *Controller) (middleware.Middleware, error) {
 	if c.Port != "http" {
 		c.TLS.Enabled = true
-	}
-
-	if c.Port == "http" {
-		c.TLS.Enabled = false
+	} else {
 		log.Printf("Warning: TLS disabled for %s://%s. To force TLS over the plaintext HTTP port, "+
 			"specify port 80 explicitly (https://%s:80).", c.Port, c.Host, c.Host)
 	}