Implement command-based echo app and HTTP handler

config.go

@@ -2,6 +2,7 @@ package ussher
 
 import (
 	"io/ioutil"
+	"net/http"
 
 	"golang.org/x/crypto/ssh"
 )
@@ -9,6 +10,11 @@ import (
 type Config struct {
 	HostKeyPath string
 	Keystore    Keystore
+	BindAddress string
+	Port        int
+	HTTPPort    int
+	SSHApps     map[string]SSHApp
+	HTTPMux     *http.ServeMux
 }
 
 func (c *Config) GetPrivateKey() (ssh.Signer, error) {
@@ -18,7 +24,3 @@ func (c *Config) GetPrivateKey() (ssh.Signer, error) {
 	}
 	return ssh.ParsePrivateKey(bytes)
 }
-
-type Keystore interface {
-	CheckPublicKey(user string, key ssh.PublicKey) (*ssh.Permissions, error)
-}