Files
crypto/ssh/knownhosts/knownhosts_test.go
T
Carlos A Becker 6b853fbea3 ssh/knownhosts: check more than one key
I believe this fixes https://github.com/golang/go/issues/36126 .

The problem was that it was keeping only the first known key of each
type found.
If you have a server advertising multiple keys of the same type,
you might get a missmatch key error.

Per sshd(8) man page, it should allow reapeatable hosts with
different host keys, although it don't specify anything about
hosts being from different types:

"It is permissible (but not recommended) to have several lines or
different host keys for the same names.  This will inevitably happen when
short forms of host names from different domains are put in the file.  It
is possible that the files contain conflicting information;
authentication is accepted if valid information can be found from either
file."

So, this changes knownhosts behavior to accept any of the keys for a
given host, regardless of type.

Fixes #36126

Change-Id: I3450ff954259a403f2471082d013a5f79def0e16
GitHub-Last-Rev: 361bd2bcd20348956aaf114ef159a5350397eaf4
GitHub-Pull-Request: golang/crypto#254
Reviewed-on: https://go-review.googlesource.com/c/crypto/+/478535
Reviewed-by: Junyang Shao <shaojunyang@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Nicola Murino <nicola.murino@gmail.com>
Reviewed-by: Michael Pratt <mpratt@google.com>
Auto-Submit: Nicola Murino <nicola.murino@gmail.com>
2025-03-06 10:51:46 -08:00

359 lines
10 KiB
Go

// Copyright 2017 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 knownhosts
import (
"bytes"
"fmt"
"net"
"reflect"
"testing"
"golang.org/x/crypto/ssh"
)
const edKeyStr = "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIGBAarftlLeoyf+v+nVchEZII/vna2PCV8FaX4vsF5BX"
const alternateEdKeyStr = "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIIXffBYeYL+WVzVru8npl5JHt2cjlr4ornFTWzoij9sx"
const ecKeyStr = "ecdsa-sha2-nistp256 AAAAE2VjZHNhLXNoYTItbmlzdHAyNTYAAAAIbmlzdHAyNTYAAABBBNLCu01+wpXe3xB5olXCN4SqU2rQu0qjSRKJO4Bg+JRCPU+ENcgdA5srTU8xYDz/GEa4dzK5ldPw4J/gZgSXCMs="
var ecKey, alternateEdKey, edKey ssh.PublicKey
var testAddr = &net.TCPAddr{
IP: net.IP{198, 41, 30, 196},
Port: 22,
}
var testAddr6 = &net.TCPAddr{
IP: net.IP{198, 41, 30, 196,
1, 2, 3, 4,
1, 2, 3, 4,
1, 2, 3, 4,
},
Port: 22,
}
func init() {
var err error
ecKey, _, _, _, err = ssh.ParseAuthorizedKey([]byte(ecKeyStr))
if err != nil {
panic(err)
}
edKey, _, _, _, err = ssh.ParseAuthorizedKey([]byte(edKeyStr))
if err != nil {
panic(err)
}
alternateEdKey, _, _, _, err = ssh.ParseAuthorizedKey([]byte(alternateEdKeyStr))
if err != nil {
panic(err)
}
}
func testDB(t *testing.T, s string) *hostKeyDB {
db := newHostKeyDB()
if err := db.Read(bytes.NewBufferString(s), "testdb"); err != nil {
t.Fatalf("Read: %v", err)
}
return db
}
func TestRevoked(t *testing.T) {
db := testDB(t, "\n\n@revoked * "+edKeyStr+"\n")
want := &RevokedError{
Revoked: KnownKey{
Key: edKey,
Filename: "testdb",
Line: 3,
},
}
if err := db.check("", &net.TCPAddr{
Port: 42,
}, edKey); err == nil {
t.Fatal("no error for revoked key")
} else if !reflect.DeepEqual(want, err) {
t.Fatalf("got %#v, want %#v", want, err)
}
}
func TestHostAuthority(t *testing.T) {
for _, m := range []struct {
authorityFor string
address string
good bool
}{
{authorityFor: "localhost", address: "localhost:22", good: true},
{authorityFor: "localhost", address: "localhost", good: false},
{authorityFor: "localhost", address: "localhost:1234", good: false},
{authorityFor: "[localhost]:1234", address: "localhost:1234", good: true},
{authorityFor: "[localhost]:1234", address: "localhost:22", good: false},
{authorityFor: "[localhost]:1234", address: "localhost", good: false},
} {
db := testDB(t, `@cert-authority `+m.authorityFor+` `+edKeyStr)
if ok := db.IsHostAuthority(db.lines[0].knownKey.Key, m.address); ok != m.good {
t.Errorf("IsHostAuthority: authority %s, address %s, wanted good = %v, got good = %v",
m.authorityFor, m.address, m.good, ok)
}
}
}
func TestBracket(t *testing.T) {
db := testDB(t, `[git.eclipse.org]:29418,[198.41.30.196]:29418 `+edKeyStr)
if err := db.check("git.eclipse.org:29418", &net.TCPAddr{
IP: net.IP{198, 41, 30, 196},
Port: 29418,
}, edKey); err != nil {
t.Errorf("got error %v, want none", err)
}
if err := db.check("git.eclipse.org:29419", &net.TCPAddr{
Port: 42,
}, edKey); err == nil {
t.Fatalf("no error for unknown address")
} else if ke, ok := err.(*KeyError); !ok {
t.Fatalf("got type %T, want *KeyError", err)
} else if len(ke.Want) > 0 {
t.Fatalf("got Want %v, want []", ke.Want)
}
}
func TestNewKeyType(t *testing.T) {
str := fmt.Sprintf("%s %s", testAddr, edKeyStr)
db := testDB(t, str)
if err := db.check("", testAddr, ecKey); err == nil {
t.Fatalf("no error for unknown address")
} else if ke, ok := err.(*KeyError); !ok {
t.Fatalf("got type %T, want *KeyError", err)
} else if len(ke.Want) == 0 {
t.Fatalf("got empty KeyError.Want")
}
}
func TestSameKeyType(t *testing.T) {
str := fmt.Sprintf("%s %s", testAddr, edKeyStr)
db := testDB(t, str)
if err := db.check("", testAddr, alternateEdKey); err == nil {
t.Fatalf("no error for unknown address")
} else if ke, ok := err.(*KeyError); !ok {
t.Fatalf("got type %T, want *KeyError", err)
} else if len(ke.Want) == 0 {
t.Fatalf("got empty KeyError.Want")
} else if got, want := ke.Want[0].Key.Marshal(), edKey.Marshal(); !bytes.Equal(got, want) {
t.Fatalf("got key %q, want %q", got, want)
}
}
func TestIPAddress(t *testing.T) {
str := fmt.Sprintf("%s %s", testAddr, edKeyStr)
db := testDB(t, str)
if err := db.check("", testAddr, edKey); err != nil {
t.Errorf("got error %q, want none", err)
}
}
func TestIPv6Address(t *testing.T) {
str := fmt.Sprintf("%s %s", testAddr6, edKeyStr)
db := testDB(t, str)
if err := db.check("", testAddr6, edKey); err != nil {
t.Errorf("got error %q, want none", err)
}
}
func TestBasic(t *testing.T) {
str := fmt.Sprintf("#comment\n\nserver.org,%s %s\notherhost %s", testAddr, edKeyStr, ecKeyStr)
db := testDB(t, str)
if err := db.check("server.org:22", testAddr, edKey); err != nil {
t.Errorf("got error %v, want none", err)
}
want := KnownKey{
Key: edKey,
Filename: "testdb",
Line: 3,
}
if err := db.check("server.org:22", testAddr, ecKey); err == nil {
t.Errorf("succeeded, want KeyError")
} else if ke, ok := err.(*KeyError); !ok {
t.Errorf("got %T, want *KeyError", err)
} else if len(ke.Want) != 1 {
t.Errorf("got %v, want 1 entry", ke)
} else if !reflect.DeepEqual(ke.Want[0], want) {
t.Errorf("got %v, want %v", ke.Want[0], want)
}
}
func TestHostNamePrecedence(t *testing.T) {
var evilAddr = &net.TCPAddr{
IP: net.IP{66, 66, 66, 66},
Port: 22,
}
str := fmt.Sprintf("server.org,%s %s\nevil.org,%s %s", testAddr, edKeyStr, evilAddr, ecKeyStr)
db := testDB(t, str)
if err := db.check("server.org:22", evilAddr, ecKey); err == nil {
t.Errorf("check succeeded")
} else if _, ok := err.(*KeyError); !ok {
t.Errorf("got %T, want *KeyError", err)
}
}
func TestNegate(t *testing.T) {
str := fmt.Sprintf("%s,!server.org %s", testAddr, edKeyStr)
db := testDB(t, str)
if err := db.check("server.org:22", testAddr, ecKey); err == nil {
t.Errorf("succeeded")
} else if ke, ok := err.(*KeyError); !ok {
t.Errorf("got error type %T, want *KeyError", err)
} else if len(ke.Want) != 0 {
t.Errorf("got expected keys %d (first of type %s), want []", len(ke.Want), ke.Want[0].Key.Type())
}
}
func TestWildcard(t *testing.T) {
str := fmt.Sprintf("server*.domain %s", edKeyStr)
db := testDB(t, str)
want := &KeyError{
Want: []KnownKey{{
Filename: "testdb",
Line: 1,
Key: edKey,
}},
}
got := db.check("server.domain:22", &net.TCPAddr{}, ecKey)
if !reflect.DeepEqual(got, want) {
t.Errorf("got %s, want %s", got, want)
}
}
func TestLine(t *testing.T) {
for in, want := range map[string]string{
"server.org": "server.org " + edKeyStr,
"server.org:22": "server.org " + edKeyStr,
"server.org:23": "[server.org]:23 " + edKeyStr,
"[c629:1ec4:102:304:102:304:102:304]:22": "[c629:1ec4:102:304:102:304:102:304] " + edKeyStr,
"[c629:1ec4:102:304:102:304:102:304]:23": "[c629:1ec4:102:304:102:304:102:304]:23 " + edKeyStr,
} {
if got := Line([]string{in}, edKey); got != want {
t.Errorf("Line(%q) = %q, want %q", in, got, want)
}
}
}
func TestWildcardMatch(t *testing.T) {
for _, c := range []struct {
pat, str string
want bool
}{
{"a?b", "abb", true},
{"ab", "abc", false},
{"abc", "ab", false},
{"a*b", "axxxb", true},
{"a*b", "axbxb", true},
{"a*b", "axbxbc", false},
{"a*?", "axbxc", true},
{"a*b*", "axxbxxxxxx", true},
{"a*b*c", "axxbxxxxxxc", true},
{"a*b*?", "axxbxxxxxxc", true},
{"a*b*z", "axxbxxbxxxz", true},
{"a*b*z", "axxbxxzxxxz", true},
{"a*b*z", "axxbxxzxxx", false},
} {
got := wildcardMatch([]byte(c.pat), []byte(c.str))
if got != c.want {
t.Errorf("wildcardMatch(%q, %q) = %v, want %v", c.pat, c.str, got, c.want)
}
}
}
// TODO(hanwen): test coverage for certificates.
const testHostname = "hostname"
// generated with keygen -H -f
const encodedTestHostnameHash = "|1|IHXZvQMvTcZTUU29+2vXFgx8Frs=|UGccIWfRVDwilMBnA3WJoRAC75Y="
func TestHostHash(t *testing.T) {
testHostHash(t, testHostname, encodedTestHostnameHash)
}
func TestHashList(t *testing.T) {
encoded := HashHostname(testHostname)
testHostHash(t, testHostname, encoded)
}
func testHostHash(t *testing.T, hostname, encoded string) {
typ, salt, hash, err := decodeHash(encoded)
if err != nil {
t.Fatalf("decodeHash: %v", err)
}
if got := encodeHash(typ, salt, hash); got != encoded {
t.Errorf("got encoding %s want %s", got, encoded)
}
if typ != sha1HashType {
t.Fatalf("got hash type %q, want %q", typ, sha1HashType)
}
got := hashHost(hostname, salt)
if !bytes.Equal(got, hash) {
t.Errorf("got hash %x want %x", got, hash)
}
}
func TestNormalize(t *testing.T) {
for in, want := range map[string]string{
"127.0.0.1:22": "127.0.0.1",
"[127.0.0.1]:22": "127.0.0.1",
"[127.0.0.1]:23": "[127.0.0.1]:23",
"127.0.0.1:23": "[127.0.0.1]:23",
"[a.b.c]:22": "a.b.c",
"[abcd:abcd:abcd:abcd]": "[abcd:abcd:abcd:abcd]",
"[abcd:abcd:abcd:abcd]:22": "[abcd:abcd:abcd:abcd]",
"[abcd:abcd:abcd:abcd]:23": "[abcd:abcd:abcd:abcd]:23",
} {
got := Normalize(in)
if got != want {
t.Errorf("Normalize(%q) = %q, want %q", in, got, want)
}
}
}
func TestHashedHostkeyCheck(t *testing.T) {
str := fmt.Sprintf("%s %s", HashHostname(testHostname), edKeyStr)
db := testDB(t, str)
if err := db.check(testHostname+":22", testAddr, edKey); err != nil {
t.Errorf("check(%s): %v", testHostname, err)
}
want := &KeyError{
Want: []KnownKey{{
Filename: "testdb",
Line: 1,
Key: edKey,
}},
}
if got := db.check(testHostname+":22", testAddr, alternateEdKey); !reflect.DeepEqual(got, want) {
t.Errorf("got error %v, want %v", got, want)
}
}
func TestIssue36126(t *testing.T) {
str := fmt.Sprintf("server.org,%s %s\nserver.org,%s %s", testAddr, edKeyStr, testAddr, alternateEdKeyStr)
db := testDB(t, str)
if err := db.check("server.org:22", testAddr, edKey); err != nil {
t.Errorf("should have passed the check, got %v", err)
}
if err := db.check("server.org:22", testAddr, alternateEdKey); err != nil {
t.Errorf("should have passed the check, got %v", err)
}
}