host download tokens

cmd/dkl-dir2config/render-context.go

@@ -301,8 +301,11 @@ func (ctx *renderContext) templateFuncs(ctxMap map[string]interface{}) map[strin
 		},
 
 		"ssh_host_keys": func(dir string) (s string) {
-			return fmt.Sprintf("{{ ssh_host_keys %q %q %q}}",
+			return fmt.Sprintf("{{ ssh_host_keys %q %q \"\"}}",
-				dir, cluster, ctx.Host.Name)
+				dir, cluster)
+		},
+		"host_download_token": func() (s string) {
+			return "{{ host_download_token }}"
 		},
 
 		"hosts_of_group": func() (hosts []interface{}) {

cmd/dkl-local-server/cluster-render-context.go

@@ -133,33 +133,6 @@ func templateFuncs(sslCfg *cfsslconfig.Config) map[string]any {
 				},
 			})
 		},
-
-		"ssh_host_keys": func(dir, cluster, host string) (s string, err error) {
-			pairs, err := getSSHKeyPairs(host)
-			if err != nil {
-				return
-			}
-
-			files := make([]config.FileDef, 0, len(pairs)*2)
-
-			for _, pair := range pairs {
-				basePath := path.Join(dir, "ssh_host_"+pair.Type+"_key")
-				files = append(files, []config.FileDef{
-					{
-						Path:    basePath,
-						Mode:    0600,
-						Content: pair.Private,
-					},
-					{
-						Path:    basePath + ".pub",
-						Mode:    0644,
-						Content: pair.Public,
-					},
-				}...)
-			}
-
-			return asYaml(files)
-		},
 	}
 }
 

cmd/dkl-local-server/host-download-tokens.go

@@ -0,0 +1,3 @@
+package main
+
+var hostDownloadTokens = KVSecrets[string]{"hosts/download-tokens"}

cmd/dkl-local-server/render-context.go

@@ -4,10 +4,12 @@ import (
 	"bytes"
 	"crypto/sha256"
 	"encoding/hex"
+	"fmt"
 	"io"
 	"log"
 	"net/http"
 	"net/url"
+	"path"
 	"path/filepath"
 	"text/template"
 
@@ -115,7 +117,7 @@ func (ctx *renderContext) BootstrapConfig() (ba []byte, cfg *bsconfig.Config, er
 
 func (ctx *renderContext) render(templateText string) (ba []byte, err error) {
 	tmpl, err := template.New(ctx.Host.Name + "/config").
-		Funcs(templateFuncs(ctx.SSLConfig)).
+		Funcs(ctx.TemplateFuncs()).
 		Parse(templateText)
 
 	if err != nil {
@@ -168,3 +170,69 @@ func asMap(v interface{}) map[string]interface{} {
 
 	return result
 }
+
+func (ctx *renderContext) TemplateFuncs() map[string]any {
+	funcs := templateFuncs(ctx.SSLConfig)
+
+	for name, method := range map[string]any{
+		"ssh_host_keys": func(dir, cluster, host string) (s string, err error) {
+			if host == "" {
+				host = ctx.Host.Name
+			}
+			if host != ctx.Host.Name {
+				err = fmt.Errorf("wrong host name")
+				return
+			}
+
+			pairs, err := getSSHKeyPairs(host)
+			if err != nil {
+				return
+			}
+
+			files := make([]config.FileDef, 0, len(pairs)*2)
+
+			for _, pair := range pairs {
+				basePath := path.Join(dir, "ssh_host_"+pair.Type+"_key")
+				files = append(files, []config.FileDef{
+					{
+						Path:    basePath,
+						Mode:    0600,
+						Content: pair.Private,
+					},
+					{
+						Path:    basePath + ".pub",
+						Mode:    0644,
+						Content: pair.Public,
+					},
+				}...)
+			}
+
+			return asYaml(files)
+		},
+		"host_download_token": func() (token string, err error) {
+			key := ctx.Host.Name
+			token, found, err := hostDownloadTokens.Get(key)
+			if err != nil {
+				return
+			}
+
+			if !found {
+				token, err = newToken(32)
+				if err != nil {
+					return
+				}
+
+				err = hostDownloadTokens.Put(key, token)
+				if err != nil {
+					return
+				}
+			}
+
+			return
+		},
+	} {
+		funcs[name] = method
+	}
+
+	return funcs
+}

cmd/dkl-local-server/ws-host.go

@@ -18,7 +18,7 @@ var trustXFF = flag.Bool("trust-xff", true, "Trust the X-Forwarded-For header")
 type wsHost struct {
 	prefix  string
 	hostDoc string
-	getHost func(req *restful.Request) string
+	getHost func(req *restful.Request) (hostName string, err error)
 }
 
 func (ws *wsHost) register(rws *restful.WebService, alterRB func(*restful.RouteBuilder)) {
@@ -105,13 +105,17 @@ func (ws *wsHost) register(rws *restful.WebService, alterRB func(*restful.RouteB
 }
 
 func (ws *wsHost) host(req *restful.Request, resp *restful.Response) (host *localconfig.Host, cfg *localconfig.Config) {
-	hostname := ws.getHost(req)
+	hostname, err := ws.getHost(req)
+	if err != nil {
+		wsError(resp, err)
+		return
+	}
 	if hostname == "" {
 		wsNotFound(req, resp)
 		return
 	}
 
-	cfg, err := readConfig()
+	cfg, err = readConfig()
 	if err != nil {
 		wsError(resp, err)
 		return

cmd/dkl-local-server/ws.go

@@ -120,8 +120,8 @@ func registerWS(rest *restful.Container) {
 	(&wsHost{
 		prefix:  "/hosts/{host-name}",
 		hostDoc: "given host",
-		getHost: func(req *restful.Request) string {
+		getHost: func(req *restful.Request) (string, error) {
-			return req.PathParameter("host-name")
+			return req.PathParameter("host-name"), nil
 		},
 	}).register(ws, func(rb *restful.RouteBuilder) {
 	})
@@ -146,10 +146,37 @@ func registerWS(rest *restful.Container) {
 		rb.Notes("In this case, the host is detected from the remote IP")
 	})
 
+	// Hosts by token API
+	ws = &restful.WebService{}
+	ws.Path("/hosts-by-token/{host-token}")
+
+	(&wsHost{
+		hostDoc: "token's host",
+		getHost: func(req *restful.Request) (host string, err error) {
+			reqToken := req.PathParameter("host-name")
+
+			data, err := hostDownloadTokens.Data()
+			if err != nil {
+				return
+			}
+
+			for h, token := range data {
+				if token == reqToken {
+					host = h
+					return
+				}
+			}
+
+			return
+		},
+	}).register(ws, func(rb *restful.RouteBuilder) {
+		rb.Notes("In this case, the host is detected from the remote IP")
+	})
+
 	rest.Add(ws)
 }
 
-func detectHost(req *restful.Request) string {
+func detectHost(req *restful.Request) (hostName string, err error) {
 	r := req.Request
 	remoteAddr := r.RemoteAddr
 
@@ -167,17 +194,17 @@ func detectHost(req *restful.Request) string {
 
 	cfg, err := readConfig()
 	if err != nil {
-		return ""
+		return
 	}
 
 	host := cfg.HostByIP(hostIP)
 
 	if host == nil {
 		log.Print("no host found for IP ", hostIP)
-		return ""
+		return
 	}
 
-	return host.Name
+	return host.Name, nil
 }
 
 func wsReadConfig(resp *restful.Response) *localconfig.Config {