Agent confirmation tests (#202)

* enable agent confirmation from config

* cleanup

* update versions

* fixing tests

* fixing typo

Makefile

@@ -10,7 +10,7 @@ endif
 BINARY=keymaster
 
 # These are the values we want to pass for Version and BuildTime
-VERSION=1.13.5
+VERSION=1.14.0
 #BUILD_TIME=`date +%FT%T%z`
 
 # Setup the -ldflags option for go build here, interpolate the variable values

cmd/keymaster/main.go

@@ -17,6 +17,9 @@ import (
 	"strings"
 	"time"
 
+	"golang.org/x/crypto/ssh"
+	"golang.org/x/crypto/ssh/agent"
+
 	"github.com/Cloud-Foundations/Dominator/lib/log/cmdlogger"
 	"github.com/Cloud-Foundations/Dominator/lib/net/rrdialer"
 	"github.com/Cloud-Foundations/golib/pkg/log"
@@ -271,9 +274,29 @@ func insertSSHCertIntoAgentORWriteToFilesystem(certText []byte,
 	filePrefix string,
 	userName string,
 	privateKeyPath string,
+	confirmBeforeUse bool,
 	logger log.DebugLogger) (err error) {
+
+	pubKey, _, _, _, err := ssh.ParseAuthorizedKey(certText)
+	if err != nil {
+		logger.Println(err)
+		return err
+	}
+	sshCert, ok := pubKey.(*ssh.Certificate)
+	if !ok {
+		return fmt.Errorf("It is not a certificate")
+	}
+	comment := filePrefix + "-" + userName
+	keyToAdd := agent.AddedKey{
+		PrivateKey:       signer,
+		Certificate:      sshCert,
+		Comment:          comment,
+		LifetimeSecs:     uint32((*twofa.Duration).Seconds()),
+		ConfirmBeforeUse: confirmBeforeUse,
+	}
+
 	//comment should be based on key type?
-	err = sshagent.UpsertCertIntoAgent(certText, signer, filePrefix+"-"+userName, uint32((*twofa.Duration).Seconds()), logger)
+	err = sshagent.WithAddedKeyUpsertCertIntoAgent(keyToAdd, logger)
 	if err == nil {
 		return nil
 	}
@@ -282,7 +305,10 @@ func insertSSHCertIntoAgentORWriteToFilesystem(certText []byte,
 	// barfs on timeouts missing, so we rety without a timeout in case
 	// we are on windows OR we have an agent running on windows thar is forwarded
 	// to us.
-	err = sshagent.UpsertCertIntoAgent(certText, signer, filePrefix+"-"+userName, 0, logger)
+	keyToAdd.LifetimeSecs = 0
+	// confirmation is also broken on windows, but since it is an opt-in security
+	// feature we never change the user preference
+	err = sshagent.WithAddedKeyUpsertCertIntoAgent(keyToAdd, logger)
 	if err == nil {
 		return nil
 	}
@@ -390,6 +416,7 @@ func setupCerts(
 	}
 	logger.Debugf(0, "certificates successfully generated")
 
+	confirmKeyUse := configContents.Base.AgentConfirmUse
 	// Time to write certs and keys
 	// old agents do not understand sha2 certs, so we inject Ed25519 first
 	// if present
@@ -399,6 +426,7 @@ func setupCerts(
 			FilePrefix+"-ed25519",
 			userName,
 			sshKeyPath+"-ed25519",
+			confirmKeyUse,
 			logger)
 		if err != nil {
 			return err
@@ -409,6 +437,7 @@ func setupCerts(
 		FilePrefix+"-rsa",
 		userName,
 		sshKeyPath+"-rsa",
+		confirmKeyUse,
 		logger)
 	if err != nil {
 		return err
@@ -502,6 +531,7 @@ func main() {
 		logger.Fatal(err)
 	}
 	config := loadConfigFile(client, logger)
+	logger.Debugf(3, "loaded Config=%+v", config)
 	// Adjust user name
 	if len(config.Base.Username) > 0 {
 		userName = config.Base.Username

cmd/keymaster/main_test.go

@@ -267,6 +267,7 @@ func TestInsertSSHCertIntoAgentORWriteToFilesystem(t *testing.T) {
 		"someprefix",
 		"username",
 		privateKeyPath,
+		false,
 		testlogger.New(t))
 	if err != nil {
 		t.Fatal(err)

keymaster.spec

@@ -1,5 +1,5 @@
 Name:           keymaster
-Version:        1.13.5
+Version:        1.14.0
 Release:        1%{?dist}
 Summary:        Short term access certificate generator and client
 

lib/client/config/api.go

@@ -7,11 +7,12 @@ import (
 )
 
 type BaseConfig struct {
-	Gen_Cert_URLS  string `yaml:"gen_cert_urls"`
-	Username       string `yaml:"username"`
-	FilePrefix     string `yaml:"file_prefix"`
-	AddGroups      bool   `yaml:"add_groups"`
-	WebauthBrowser string `yaml:"webauth_browser"`
+	Gen_Cert_URLS   string `yaml:"gen_cert_urls"`
+	Username        string `yaml:"username"`
+	FilePrefix      string `yaml:"file_prefix"`
+	AddGroups       bool   `yaml:"add_groups"`
+	WebauthBrowser  string `yaml:"webauth_browser"`
+	AgentConfirmUse bool   `yaml:"agent_confirm_use"`
 }
 
 // AppConfigFile represents a keymaster client configuration file

lib/client/sshagent/agent.go

@@ -55,6 +55,7 @@ func upsertCertIntoAgent(
 	privateKey interface{},
 	comment string,
 	lifeTimeSecs uint32,
+	confirmBeforeUse bool,
 	logger log.Logger) error {
 	pubKey, _, _, _, err := ssh.ParseAuthorizedKey(certText)
 	if err != nil {
@@ -65,6 +66,20 @@ func upsertCertIntoAgent(
 	if !ok {
 		return fmt.Errorf("It is not a certificate")
 	}
+	keyToAdd := agent.AddedKey{
+		PrivateKey:       privateKey,
+		Certificate:      sshCert,
+		Comment:          comment,
+		ConfirmBeforeUse: confirmBeforeUse,
+	}
+	return withAddedKeyUpsertCertIntoAgent(keyToAdd, logger)
+}
+
+func withAddedKeyUpsertCertIntoAgent(certToAdd agent.AddedKey, logger log.Logger) error {
+	if certToAdd.Certificate == nil {
+		return fmt.Errorf("Needs a certificate to be added")
+	}
+
 	conn, err := connectToDefaultSSHAgentLocation()
 	if err != nil {
 		return err
@@ -73,22 +88,17 @@ func upsertCertIntoAgent(
 	agentClient := agent.NewClient(conn)
 
 	//delete certs in agent with the same comment
-	_, err = deleteDuplicateEntries(comment, agentClient, logger)
+	_, err = deleteDuplicateEntries(certToAdd.Comment, agentClient, logger)
 	if err != nil {
 		logger.Printf("failed during deletion err=%s", err)
 		return err
 	}
-
-	keyToAdd := agent.AddedKey{
-		PrivateKey:  privateKey,
-		Certificate: sshCert,
-		Comment:     comment,
-	}
 	// NOTE: Current Windows ssh (OpenSSH_for_Windows_7.7p1, LibreSSL 2.6.5)
 	// barfs when encountering a lifetime so we only add it for non-windows
-	if runtime.GOOS != "windows" {
-		keyToAdd.LifetimeSecs = lifeTimeSecs
+	if runtime.GOOS == "windows" {
+		certToAdd.LifetimeSecs = 0
+		certToAdd.ConfirmBeforeUse = false
 	}
 
-	return agentClient.Add(keyToAdd)
+	return agentClient.Add(certToAdd)
 }

lib/client/sshagent/api.go

@@ -1,6 +1,8 @@
 package sshagent
 
 import (
+	"golang.org/x/crypto/ssh/agent"
+
 	"github.com/Cloud-Foundations/golib/pkg/log"
 )
 
@@ -10,5 +12,9 @@ func UpsertCertIntoAgent(
 	comment string,
 	lifeTimeSecs uint32,
 	logger log.Logger) error {
-	return upsertCertIntoAgent(certText, privateKey, comment, lifeTimeSecs, logger)
+	return upsertCertIntoAgent(certText, privateKey, comment, lifeTimeSecs, false, logger)
+}
+
+func WithAddedKeyUpsertCertIntoAgent(certToAdd agent.AddedKey, logger log.Logger) error {
+	return withAddedKeyUpsertCertIntoAgent(certToAdd, logger)
 }