Add endpoint to return the SSH public keys.

Related to smallstep/ca-component#195

api/api.go

@@ -250,9 +250,12 @@ func (h *caHandler) Route(r Router) {
 	r.MethodFunc("GET", "/provisioners/{kid}/encrypted-key", h.ProvisionerKey)
 	r.MethodFunc("GET", "/roots", h.Roots)
 	r.MethodFunc("GET", "/federation", h.Federation)
+	// SSH CA
+	r.MethodFunc("GET", "/ssh/sign", h.SignSSH)
+	r.MethodFunc("GET", "/ssh/keys", h.SSHKeys)
+
 	// For compatibility with old code:
 	r.MethodFunc("POST", "/re-sign", h.Renew)
-	// SSH CA
 	r.MethodFunc("POST", "/sign-ssh", h.SignSSH)
 }
 

api/api_test.go

@@ -512,6 +512,7 @@ type mockAuthority struct {
 	getEncryptedKey              func(kid string) (string, error)
 	getRoots                     func() ([]*x509.Certificate, error)
 	getFederation                func() ([]*x509.Certificate, error)
+	getSSHKeys                   func() (*authority.SSHKeys, error)
 }
 
 // TODO: remove once Authorize is deprecated.
@@ -617,6 +618,13 @@ func (m *mockAuthority) GetFederation() ([]*x509.Certificate, error) {
 	return m.ret1.([]*x509.Certificate), m.err
 }
 
+func (m *mockAuthority) GetSSHKeys() (*authority.SSHKeys, error) {
+	if m.getSSHKeys != nil {
+		return m.getSSHKeys()
+	}
+	return m.ret1.(*authority.SSHKeys), m.err
+}
+
 func Test_caHandler_Route(t *testing.T) {
 	type fields struct {
 		Authority Authority

api/ssh.go

@@ -16,7 +16,7 @@ import (
 type SSHAuthority interface {
 	SignSSH(key ssh.PublicKey, opts provisioner.SSHOptions, signOpts ...provisioner.SignOption) (*ssh.Certificate, error)
 	SignSSHAddUser(key ssh.PublicKey, cert *ssh.Certificate) (*ssh.Certificate, error)
-	SSHConfig() (*authority.SSHConfiguration, error)
+	GetSSHKeys() (*authority.SSHKeys, error)
 }
 
 // SignSSHRequest is the request body of an SSH certificate request.
@@ -30,15 +30,29 @@ type SignSSHRequest struct {
 	AddUserPublicKey []byte       `json:"addUserPublicKey,omitempty"`
 }
 
+// Validate validates the SignSSHRequest.
+func (s *SignSSHRequest) Validate() error {
+	switch {
+	case s.CertType != "" && s.CertType != provisioner.SSHUserCert && s.CertType != provisioner.SSHHostCert:
+		return errors.Errorf("unknown certType %s", s.CertType)
+	case len(s.PublicKey) == 0:
+		return errors.New("missing or empty publicKey")
+	case len(s.OTT) == 0:
+		return errors.New("missing or empty ott")
+	default:
+		return nil
+	}
+}
+
 // SignSSHResponse is the response object that returns the SSH certificate.
 type SignSSHResponse struct {
 	Certificate        SSHCertificate  `json:"crt"`
 	AddUserCertificate *SSHCertificate `json:"addUserCrt,omitempty"`
 }
 
-// SSHConfigResponse represents the response object that returns the SSH user
-// and host keys.
-type SSHConfigResponse struct {
+// SSHKeysResponse represents the response object that returns the SSH user and
+// host keys.
+type SSHKeysResponse struct {
 	UserKey *SSHPublicKey `json:"userKey,omitempty"`
 	HostKey *SSHPublicKey `json:"hostKey,omitempty"`
 }
@@ -58,21 +72,6 @@ func (c SSHCertificate) MarshalJSON() ([]byte, error) {
 	return []byte(`"` + s + `"`), nil
 }
 
-// SSHPublicKey represents a public key in a response object.
-type SSHPublicKey struct {
-	ssh.PublicKey
-}
-
-// MarshalJSON implements the json.Marshaler interface. Returns a quoted,
-// base64 encoded, openssh wire format version of the public key.
-func (p *SSHPublicKey) MarshalJSON() ([]byte, error) {
-	if p == nil || p.PublicKey == nil {
-		return []byte("null"), nil
-	}
-	s := base64.StdEncoding.EncodeToString(p.PublicKey.Marshal())
-	return []byte(`"` + s + `"`), nil
-}
-
 // UnmarshalJSON implements the json.Unmarshaler interface. The certificate is
 // expected to be a quoted, base64 encoded, openssh wire formatted block of bytes.
 func (c *SSHCertificate) UnmarshalJSON(data []byte) error {
@@ -100,18 +99,43 @@ func (c *SSHCertificate) UnmarshalJSON(data []byte) error {
 	return nil
 }
 
-// Validate validates the SignSSHRequest.
-func (s *SignSSHRequest) Validate() error {
-	switch {
-	case s.CertType != "" && s.CertType != provisioner.SSHUserCert && s.CertType != provisioner.SSHHostCert:
-		return errors.Errorf("unknown certType %s", s.CertType)
-	case len(s.PublicKey) == 0:
-		return errors.New("missing or empty publicKey")
-	case len(s.OTT) == 0:
-		return errors.New("missing or empty ott")
-	default:
+// SSHPublicKey represents a public key in a response object.
+type SSHPublicKey struct {
+	ssh.PublicKey
+}
+
+// MarshalJSON implements the json.Marshaler interface. Returns a quoted,
+// base64 encoded, openssh wire format version of the public key.
+func (p *SSHPublicKey) MarshalJSON() ([]byte, error) {
+	if p == nil || p.PublicKey == nil {
+		return []byte("null"), nil
+	}
+	s := base64.StdEncoding.EncodeToString(p.PublicKey.Marshal())
+	return []byte(`"` + s + `"`), nil
+}
+
+// UnmarshalJSON implements the json.Unmarshaler interface. The public key is
+// expected to be a quoted, base64 encoded, openssh wire formatted block of
+// bytes.
+func (p *SSHPublicKey) UnmarshalJSON(data []byte) error {
+	var s string
+	if err := json.Unmarshal(data, &s); err != nil {
+		return errors.Wrap(err, "error decoding ssh public key")
+	}
+	if s == "" {
+		p.PublicKey = nil
 		return nil
 	}
+	data, err := base64.StdEncoding.DecodeString(s)
+	if err != nil {
+		return errors.Wrap(err, "error decoding ssh public key")
+	}
+	pub, err := ssh.ParsePublicKey(data)
+	if err != nil {
+		return errors.Wrap(err, "error parsing ssh public key")
+	}
+	p.PublicKey = pub
+	return nil
 }
 
 // SignSSH is an HTTP handler that reads an SignSSHRequest with a one-time-token
@@ -182,24 +206,24 @@ func (h *caHandler) SignSSH(w http.ResponseWriter, r *http.Request) {
 	})
 }
 
-// SSHConfig is an HTTP handler that returns the SSH public keys for user and
-// host certificates.
-func (h *caHandler) SSHConfig(w http.ResponseWriter, r *http.Request) {
-	config, err := h.Authority.SSHConfig()
+// SSHKeys is an HTTP handler that returns the SSH public keys for user and host
+// certificates.
+func (h *caHandler) SSHKeys(w http.ResponseWriter, r *http.Request) {
+	keys, err := h.Authority.GetSSHKeys()
 	if err != nil {
 		WriteError(w, NotFound(err))
 		return
 	}
 
 	var host, user *SSHPublicKey
-	if config.HostKey != nil {
-		host = &SSHPublicKey{config.HostKey}
+	if keys.HostKey != nil {
+		host = &SSHPublicKey{PublicKey: keys.HostKey}
 	}
-	if config.UserKey != nil {
-		user = &SSHPublicKey{config.UserKey}
+	if keys.UserKey != nil {
+		user = &SSHPublicKey{PublicKey: keys.UserKey}
 	}
 
-	JSON(w, &SSHConfigResponse{
+	JSON(w, &SSHKeysResponse{
 		HostKey: host,
 		UserKey: user,
 	})

api/ssh_test.go

@@ -16,6 +16,7 @@ import (
 	"time"
 
 	"github.com/smallstep/assert"
+	"github.com/smallstep/certificates/authority"
 	"github.com/smallstep/certificates/authority/provisioner"
 	"github.com/smallstep/certificates/logging"
 	"golang.org/x/crypto/ssh"
@@ -296,23 +297,75 @@ func Test_caHandler_SignSSH(t *testing.T) {
 				},
 			}).(*caHandler)
 
-			req := httptest.NewRequest("POST", "http://example.com/sign-ssh", bytes.NewReader(tt.req))
+			req := httptest.NewRequest("POST", "http://example.com/ssh/sign", bytes.NewReader(tt.req))
 			w := httptest.NewRecorder()
 			h.SignSSH(logging.NewResponseLogger(w), req)
 			res := w.Result()
 
 			if res.StatusCode != tt.statusCode {
-				t.Errorf("caHandler.Root StatusCode = %d, wants %d", res.StatusCode, tt.statusCode)
+				t.Errorf("caHandler.SignSSH StatusCode = %d, wants %d", res.StatusCode, tt.statusCode)
 			}
 
 			body, err := ioutil.ReadAll(res.Body)
 			res.Body.Close()
 			if err != nil {
-				t.Errorf("caHandler.Root unexpected error = %v", err)
+				t.Errorf("caHandler.SignSSH unexpected error = %v", err)
 			}
 			if tt.statusCode < http.StatusBadRequest {
 				if !bytes.Equal(bytes.TrimSpace(body), tt.body) {
-					t.Errorf("caHandler.Root Body = %s, wants %s", body, tt.body)
+					t.Errorf("caHandler.SignSSH Body = %s, wants %s", body, tt.body)
+				}
+			}
+		})
+	}
+}
+
+func Test_caHandler_SSHKeys(t *testing.T) {
+	user, err := ssh.NewPublicKey(sshUserKey.Public())
+	assert.FatalError(t, err)
+	userB64 := base64.StdEncoding.EncodeToString(user.Marshal())
+
+	host, err := ssh.NewPublicKey(sshHostKey.Public())
+	assert.FatalError(t, err)
+	hostB64 := base64.StdEncoding.EncodeToString(host.Marshal())
+
+	tests := []struct {
+		name       string
+		keys       *authority.SSHKeys
+		keysErr    error
+		body       []byte
+		statusCode int
+	}{
+		{"ok", &authority.SSHKeys{HostKey: host, UserKey: user}, nil, []byte(fmt.Sprintf(`{"userKey":"%s","hostKey":"%s"}`, userB64, hostB64)), http.StatusOK},
+		{"user", &authority.SSHKeys{UserKey: user}, nil, []byte(fmt.Sprintf(`{"userKey":"%s"}`, userB64)), http.StatusOK},
+		{"host", &authority.SSHKeys{HostKey: host}, nil, []byte(fmt.Sprintf(`{"hostKey":"%s"}`, hostB64)), http.StatusOK},
+		{"error", nil, fmt.Errorf("an error"), nil, http.StatusNotFound},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			h := New(&mockAuthority{
+				getSSHKeys: func() (*authority.SSHKeys, error) {
+					return tt.keys, tt.keysErr
+				},
+			}).(*caHandler)
+
+			req := httptest.NewRequest("GET", "http://example.com/ssh/keys", http.NoBody)
+			w := httptest.NewRecorder()
+			h.SSHKeys(logging.NewResponseLogger(w), req)
+			res := w.Result()
+
+			if res.StatusCode != tt.statusCode {
+				t.Errorf("caHandler.SSHKeys StatusCode = %d, wants %d", res.StatusCode, tt.statusCode)
+			}
+
+			body, err := ioutil.ReadAll(res.Body)
+			res.Body.Close()
+			if err != nil {
+				t.Errorf("caHandler.SSHKeys unexpected error = %v", err)
+			}
+			if tt.statusCode < http.StatusBadRequest {
+				if !bytes.Equal(bytes.TrimSpace(body), tt.body) {
+					t.Errorf("caHandler.SSHKeys Body = %s, wants %s", body, tt.body)
 				}
 			}
 		})

authority/ssh.go

@@ -24,28 +24,28 @@ const (
 	SSHAddUserCommand = "sudo useradd -m <principal>; nc -q0 localhost 22"
 )
 
-// SSHConfiguration is the return type for SSHConfig.
-type SSHConfiguration struct {
+// SSHKeys represents the SSH User and Host public keys.
+type SSHKeys struct {
 	UserKey ssh.PublicKey
 	HostKey ssh.PublicKey
 }
 
-// SSHConfig returns the SSH User and Host public keys.
-func (a *Authority) SSHConfig() (*SSHConfiguration, error) {
-	var config SSHConfiguration
+// GetSSHKeys returns the SSH User and Host public keys.
+func (a *Authority) GetSSHKeys() (*SSHKeys, error) {
+	var keys SSHKeys
 	if a.sshCAUserCertSignKey != nil {
-		config.UserKey = a.sshCAUserCertSignKey.PublicKey()
+		keys.UserKey = a.sshCAUserCertSignKey.PublicKey()
 	}
 	if a.sshCAHostCertSignKey != nil {
-		config.HostKey = a.sshCAHostCertSignKey.PublicKey()
+		keys.HostKey = a.sshCAHostCertSignKey.PublicKey()
 	}
-	if config.UserKey == nil && config.HostKey == nil {
+	if keys.UserKey == nil && keys.HostKey == nil {
 		return nil, &apiError{
 			err:  errors.New("sshConfig: ssh is not configured"),
 			code: http.StatusNotFound,
 		}
 	}
-	return &config, nil
+	return &keys, nil
 }
 
 // SignSSH creates a signed SSH certificate with the given public key and options.

ca/client.go

@@ -380,7 +380,7 @@ func (c *Client) SignSSH(req *api.SignSSHRequest) (*api.SignSSHResponse, error)
 	if err != nil {
 		return nil, errors.Wrap(err, "error marshaling request")
 	}
-	u := c.endpoint.ResolveReference(&url.URL{Path: "/sign-ssh"})
+	u := c.endpoint.ResolveReference(&url.URL{Path: "/ssh/sign"})
 	resp, err := c.client.Post(u.String(), "application/json", bytes.NewReader(body))
 	if err != nil {
 		return nil, errors.Wrapf(err, "client POST %s failed", u)
@@ -527,6 +527,24 @@ func (c *Client) Federation() (*api.FederationResponse, error) {
 	return &federation, nil
 }
 
+// SSHKeys performs the get ssh keys request to the CA and returns the
+// api.SSHKeysResponse struct.
+func (c *Client) SSHKeys() (*api.SSHKeysResponse, error) {
+	u := c.endpoint.ResolveReference(&url.URL{Path: "/ssh/keys"})
+	resp, err := c.client.Get(u.String())
+	if err != nil {
+		return nil, errors.Wrapf(err, "client GET %s failed", u)
+	}
+	if resp.StatusCode >= 400 {
+		return nil, readError(resp.Body)
+	}
+	var keys api.SSHKeysResponse
+	if err := readJSON(resp.Body, &keys); err != nil {
+		return nil, errors.Wrapf(err, "error reading %s", u)
+	}
+	return &keys, nil
+}
+
 // RootFingerprint is a helper method that returns the current root fingerprint.
 // It does an health connection and gets the fingerprint from the TLS verified
 // chains.

ca/client_test.go

@@ -2,6 +2,9 @@ package ca
 
 import (
 	"bytes"
+	"crypto/ecdsa"
+	"crypto/elliptic"
+	"crypto/rand"
 	"crypto/x509"
 	"encoding/json"
 	"encoding/pem"
@@ -17,6 +20,7 @@ import (
 	"github.com/smallstep/certificates/api"
 	"github.com/smallstep/certificates/authority/provisioner"
 	"github.com/smallstep/cli/crypto/x509util"
+	"golang.org/x/crypto/ssh"
 )
 
 const (
@@ -96,6 +100,14 @@ DCbKzWTW8lqVdp9Kyf7XEhhc2R8C5w==
 -----END CERTIFICATE REQUEST-----`
 )
 
+func mustKey() *ecdsa.PrivateKey {
+	priv, err := ecdsa.GenerateKey(elliptic.P256(), rand.Reader)
+	if err != nil {
+		panic(err)
+	}
+	return priv
+}
+
 func parseCertificate(data string) *x509.Certificate {
 	block, _ := pem.Decode([]byte(data))
 	if block == nil {
@@ -710,6 +722,67 @@ func TestClient_Federation(t *testing.T) {
 	}
 }
 
+func TestClient_SSHKeys(t *testing.T) {
+	key, err := ssh.NewPublicKey(mustKey().Public())
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	ok := &api.SSHKeysResponse{
+		HostKey: &api.SSHPublicKey{PublicKey: key},
+		UserKey: &api.SSHPublicKey{PublicKey: key},
+	}
+	notFound := api.NotFound(fmt.Errorf("Not Found"))
+
+	tests := []struct {
+		name         string
+		response     interface{}
+		responseCode int
+		wantErr      bool
+	}{
+		{"ok", ok, 200, false},
+		{"not found", notFound, 404, true},
+	}
+
+	srv := httptest.NewServer(nil)
+	defer srv.Close()
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			c, err := NewClient(srv.URL, WithTransport(http.DefaultTransport))
+			if err != nil {
+				t.Errorf("NewClient() error = %v", err)
+				return
+			}
+
+			srv.Config.Handler = http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
+				api.JSONStatus(w, tt.response, tt.responseCode)
+			})
+
+			got, err := c.SSHKeys()
+			if (err != nil) != tt.wantErr {
+				fmt.Printf("%+v", err)
+				t.Errorf("Client.SSHKeys() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+
+			switch {
+			case err != nil:
+				if got != nil {
+					t.Errorf("Client.SSHKeys() = %v, want nil", got)
+				}
+				if !reflect.DeepEqual(err, tt.response) {
+					t.Errorf("Client.SSHKeys() error = %v, want %v", err, tt.response)
+				}
+			default:
+				if !reflect.DeepEqual(got, tt.response) {
+					t.Errorf("Client.SSHKeys() = %v, want %v", got, tt.response)
+				}
+			}
+		})
+	}
+}
+
 func Test_parseEndpoint(t *testing.T) {
 	expected1 := &url.URL{Scheme: "https", Host: "ca.smallstep.com"}
 	expected2 := &url.URL{Scheme: "https", Host: "ca.smallstep.com", Path: "/1.0/sign"}