Files
crypto/ssh/certs_test.go
T
Peter Moody 527d12e535 ssh/knownhosts: add IsHostAuthority.
This is a breaking change.

This adds a new hostkey callback which takes the hostname field
restrictions into account when validating host certificates.

Prior to this, a known_hosts file with the following entry

  @cert-authority *.example.com ssh-rsa <example.com public key>

would, when passed to knownhosts.New() generate an ssh.HostKeyCallback
that would accept all host certificates signed by the example.com public
key, no matter what host the client was connecting to.

After this change, that known_hosts entry can only be used to validate
host certificates presented when connecting to hosts under *.example.com

This also renames IsAuthority to IsUserAuthority to make its intended
purpose more clear.

Change-Id: I7188a53fdd40a8c0bc21983105317b3498f567bb
Reviewed-on: https://go-review.googlesource.com/41751
Reviewed-by: Han-Wen Nienhuys <hanwen@google.com>
Run-TryBot: Han-Wen Nienhuys <hanwen@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-05-02 11:58:17 +00:00

217 lines
8.3 KiB
Go

// Copyright 2013 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package ssh
import (
"bytes"
"crypto/rand"
"reflect"
"testing"
"time"
)
// Cert generated by ssh-keygen 6.0p1 Debian-4.
// % ssh-keygen -s ca-key -I test user-key
const exampleSSHCert = `ssh-rsa-cert-v01@openssh.com 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`
func TestParseCert(t *testing.T) {
authKeyBytes := []byte(exampleSSHCert)
key, _, _, rest, err := ParseAuthorizedKey(authKeyBytes)
if err != nil {
t.Fatalf("ParseAuthorizedKey: %v", err)
}
if len(rest) > 0 {
t.Errorf("rest: got %q, want empty", rest)
}
if _, ok := key.(*Certificate); !ok {
t.Fatalf("got %v (%T), want *Certificate", key, key)
}
marshaled := MarshalAuthorizedKey(key)
// Before comparison, remove the trailing newline that
// MarshalAuthorizedKey adds.
marshaled = marshaled[:len(marshaled)-1]
if !bytes.Equal(authKeyBytes, marshaled) {
t.Errorf("marshaled certificate does not match original: got %q, want %q", marshaled, authKeyBytes)
}
}
// Cert generated by ssh-keygen OpenSSH_6.8p1 OS X 10.10.3
// % ssh-keygen -s ca -I testcert -O source-address=192.168.1.0/24 -O force-command=/bin/sleep user.pub
// user.pub key: ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDACh1rt2DXfV3hk6fszSQcQ/rueMId0kVD9U7nl8cfEnFxqOCrNT92g4laQIGl2mn8lsGZfTLg8ksHq3gkvgO3oo/0wHy4v32JeBOHTsN5AL4gfHNEhWeWb50ev47hnTsRIt9P4dxogeUo/hTu7j9+s9lLpEQXCvq6xocXQt0j8MV9qZBBXFLXVT3cWIkSqOdwt/5ZBg+1GSrc7WfCXVWgTk4a20uPMuJPxU4RQwZW6X3+O8Pqo8C3cW0OzZRFP6gUYUKUsTI5WntlS+LAxgw1mZNsozFGdbiOPRnEryE3SRldh9vjDR3tin1fGpA5P7+CEB/bqaXtG3V+F2OkqaMN
// Critical Options:
// force-command /bin/sleep
// source-address 192.168.1.0/24
// Extensions:
// permit-X11-forwarding
// permit-agent-forwarding
// permit-port-forwarding
// permit-pty
// permit-user-rc
const exampleSSHCertWithOptions = `ssh-rsa-cert-v01@openssh.com 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`
func TestParseCertWithOptions(t *testing.T) {
opts := map[string]string{
"source-address": "192.168.1.0/24",
"force-command": "/bin/sleep",
}
exts := map[string]string{
"permit-X11-forwarding": "",
"permit-agent-forwarding": "",
"permit-port-forwarding": "",
"permit-pty": "",
"permit-user-rc": "",
}
authKeyBytes := []byte(exampleSSHCertWithOptions)
key, _, _, rest, err := ParseAuthorizedKey(authKeyBytes)
if err != nil {
t.Fatalf("ParseAuthorizedKey: %v", err)
}
if len(rest) > 0 {
t.Errorf("rest: got %q, want empty", rest)
}
cert, ok := key.(*Certificate)
if !ok {
t.Fatalf("got %v (%T), want *Certificate", key, key)
}
if !reflect.DeepEqual(cert.CriticalOptions, opts) {
t.Errorf("unexpected critical options - got %v, want %v", cert.CriticalOptions, opts)
}
if !reflect.DeepEqual(cert.Extensions, exts) {
t.Errorf("unexpected Extensions - got %v, want %v", cert.Extensions, exts)
}
marshaled := MarshalAuthorizedKey(key)
// Before comparison, remove the trailing newline that
// MarshalAuthorizedKey adds.
marshaled = marshaled[:len(marshaled)-1]
if !bytes.Equal(authKeyBytes, marshaled) {
t.Errorf("marshaled certificate does not match original: got %q, want %q", marshaled, authKeyBytes)
}
}
func TestValidateCert(t *testing.T) {
key, _, _, _, err := ParseAuthorizedKey([]byte(exampleSSHCert))
if err != nil {
t.Fatalf("ParseAuthorizedKey: %v", err)
}
validCert, ok := key.(*Certificate)
if !ok {
t.Fatalf("got %v (%T), want *Certificate", key, key)
}
checker := CertChecker{}
checker.IsUserAuthority = func(k PublicKey) bool {
return bytes.Equal(k.Marshal(), validCert.SignatureKey.Marshal())
}
if err := checker.CheckCert("user", validCert); err != nil {
t.Errorf("Unable to validate certificate: %v", err)
}
invalidCert := &Certificate{
Key: testPublicKeys["rsa"],
SignatureKey: testPublicKeys["ecdsa"],
ValidBefore: CertTimeInfinity,
Signature: &Signature{},
}
if err := checker.CheckCert("user", invalidCert); err == nil {
t.Error("Invalid cert signature passed validation")
}
}
func TestValidateCertTime(t *testing.T) {
cert := Certificate{
ValidPrincipals: []string{"user"},
Key: testPublicKeys["rsa"],
ValidAfter: 50,
ValidBefore: 100,
}
cert.SignCert(rand.Reader, testSigners["ecdsa"])
for ts, ok := range map[int64]bool{
25: false,
50: true,
99: true,
100: false,
125: false,
} {
checker := CertChecker{
Clock: func() time.Time { return time.Unix(ts, 0) },
}
checker.IsUserAuthority = func(k PublicKey) bool {
return bytes.Equal(k.Marshal(),
testPublicKeys["ecdsa"].Marshal())
}
if v := checker.CheckCert("user", &cert); (v == nil) != ok {
t.Errorf("Authenticate(%d): %v", ts, v)
}
}
}
// TODO(hanwen): tests for
//
// host keys:
// * fallbacks
func TestHostKeyCert(t *testing.T) {
cert := &Certificate{
ValidPrincipals: []string{"hostname", "hostname.domain", "otherhost"},
Key: testPublicKeys["rsa"],
ValidBefore: CertTimeInfinity,
CertType: HostCert,
}
cert.SignCert(rand.Reader, testSigners["ecdsa"])
checker := &CertChecker{
IsHostAuthority: func(p PublicKey, h string) bool {
return h == "hostname" && bytes.Equal(testPublicKeys["ecdsa"].Marshal(), p.Marshal())
},
}
certSigner, err := NewCertSigner(cert, testSigners["rsa"])
if err != nil {
t.Errorf("NewCertSigner: %v", err)
}
for _, name := range []string{"hostname", "otherhost", "lasthost"} {
c1, c2, err := netPipe()
if err != nil {
t.Fatalf("netPipe: %v", err)
}
defer c1.Close()
defer c2.Close()
errc := make(chan error)
go func() {
conf := ServerConfig{
NoClientAuth: true,
}
conf.AddHostKey(certSigner)
_, _, _, err := NewServerConn(c1, &conf)
errc <- err
}()
config := &ClientConfig{
User: "user",
HostKeyCallback: checker.CheckHostKey,
}
_, _, _, err = NewClientConn(c2, name, config)
succeed := name == "hostname"
if (err == nil) != succeed {
t.Fatalf("NewClientConn(%q): %v", name, err)
}
err = <-errc
if (err == nil) != succeed {
t.Fatalf("NewServerConn(%q): %v", name, err)
}
}
}