WIP: make SSH package dedicated submodule
This commit is contained in:
Hidde Beydals
13
ssh/Makefile
Normal file
13
ssh/Makefile
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@@ -0,0 +1,13 @@
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all: test
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tidy:
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go mod tidy
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fmt:
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go fmt ./...
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vet:
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go vet ./...
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test: tidy fmt vet
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go test ./... -coverprofile cover.out
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5
ssh/go.mod
Normal file
5
ssh/go.mod
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@@ -0,0 +1,5 @@
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module github.com/fluxcd/toolkit/ssh
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go 1.14
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require golang.org/x/crypto v0.0.0-20200604202706-70a84ac30bf9
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8
ssh/go.sum
Normal file
8
ssh/go.sum
Normal file
@@ -0,0 +1,8 @@
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golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
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golang.org/x/crypto v0.0.0-20200604202706-70a84ac30bf9 h1:vEg9joUBmeBcK9iSJftGNf3coIG4HqZElCPehJsfAYM=
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golang.org/x/crypto v0.0.0-20200604202706-70a84ac30bf9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
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golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
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golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
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golang.org/x/sys v0.0.0-20190412213103-97732733099d h1:+R4KGOnez64A81RvjARKc4UT5/tI9ujCIVX+P5KiHuI=
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golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
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golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
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71
ssh/host_key.go
Normal file
71
ssh/host_key.go
Normal file
@@ -0,0 +1,71 @@
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/*
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Copyright 2020 The Flux CD contributors.
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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*/
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package ssh
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import (
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"encoding/base64"
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"fmt"
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"net"
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"time"
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"golang.org/x/crypto/ssh"
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"golang.org/x/crypto/ssh/knownhosts"
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)
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// ScanHostKey collects the given host's preferred public key for the
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// Any errors (e.g. authentication failures) are ignored, except if
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// no key could be collected from the host.
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func ScanHostKey(host string, timeout time.Duration) ([]byte, error) {
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col := &HostKeyCollector{}
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config := &ssh.ClientConfig{
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HostKeyCallback: col.StoreKey(),
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Timeout: timeout,
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}
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client, err := ssh.Dial("tcp", host, config)
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if err == nil {
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defer client.Close()
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}
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if len(col.knownKeys) > 0 {
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return col.knownKeys, nil
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}
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return col.knownKeys, err
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}
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// HostKeyCollector offers a StoreKey method which provides an
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// HostKeyCallBack to collect public keys from an SSH server.
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type HostKeyCollector struct {
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knownKeys []byte
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}
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// StoreKey stores the public key in bytes as returned by the host.
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// To collect multiple public key types from the host, multiple
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// SSH dials need with the ClientConfig HostKeyAlgorithms set to
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// the algorithm you want to collect.
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func (c *HostKeyCollector) StoreKey() ssh.HostKeyCallback {
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return func(hostname string, remote net.Addr, key ssh.PublicKey) error {
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c.knownKeys = append(
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c.knownKeys,
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fmt.Sprintf("%s %s %s\n", knownhosts.Normalize(hostname), key.Type(), base64.StdEncoding.EncodeToString(key.Marshal()))...,
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)
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return nil
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}
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}
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// GetKnownKeys returns the collected public keys in bytes.
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func (c *HostKeyCollector) GetKnownKeys() []byte {
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return c.knownKeys
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}
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146
ssh/key_pair.go
Normal file
146
ssh/key_pair.go
Normal file
@@ -0,0 +1,146 @@
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/*
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Copyright 2020 The Flux CD contributors.
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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*/
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package ssh
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import (
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"crypto/ecdsa"
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"crypto/ed25519"
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"crypto/elliptic"
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"crypto/rand"
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"crypto/rsa"
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"crypto/x509"
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"encoding/pem"
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"golang.org/x/crypto/ssh"
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)
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// KeyPair holds the public and private key PEM block bytes.
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type KeyPair struct {
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PublicKey []byte
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PrivateKey []byte
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}
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type KeyPairGenerator interface {
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Generate() (*KeyPair, error)
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}
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type RSAGenerator struct {
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bits int
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}
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func NewRSAGenerator(bits int) KeyPairGenerator {
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return &RSAGenerator{bits}
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}
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func (g *RSAGenerator) Generate() (*KeyPair, error) {
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pk, err := rsa.GenerateKey(rand.Reader, g.bits)
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if err != nil {
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return nil, err
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}
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err = pk.Validate()
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if err != nil {
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return nil, err
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}
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pub, err := generatePublicKey(&pk.PublicKey)
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if err != nil {
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return nil, err
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}
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priv, err := encodePrivateKeyToPEM(pk)
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if err != nil {
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return nil, err
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}
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return &KeyPair{
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PublicKey: pub,
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PrivateKey: priv,
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}, nil
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}
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type ECDSAGenerator struct {
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c elliptic.Curve
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}
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func NewECDSAGenerator(c elliptic.Curve) KeyPairGenerator {
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return &ECDSAGenerator{c}
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}
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func (g *ECDSAGenerator) Generate() (*KeyPair, error) {
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pk, err := ecdsa.GenerateKey(g.c, rand.Reader)
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if err != nil {
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return nil, err
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}
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pub, err := generatePublicKey(&pk.PublicKey)
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if err != nil {
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return nil, err
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}
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priv, err := encodePrivateKeyToPEM(pk)
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if err != nil {
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return nil, err
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}
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return &KeyPair{
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PublicKey: pub,
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PrivateKey: priv,
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}, nil
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}
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type Ed25519Generator struct{}
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func NewEd25519Generator() KeyPairGenerator {
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return &Ed25519Generator{}
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}
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func (g *Ed25519Generator) Generate() (*KeyPair, error) {
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pk, pv, err := ed25519.GenerateKey(rand.Reader)
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if err != nil {
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return nil, err
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}
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pub, err := generatePublicKey(pk)
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if err != nil {
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return nil, err
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}
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priv, err := encodePrivateKeyToPEM(pv)
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if err != nil {
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return nil, err
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}
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return &KeyPair{
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PublicKey: pub,
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PrivateKey: priv,
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}, nil
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}
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func generatePublicKey(pk interface{}) ([]byte, error) {
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b, err := ssh.NewPublicKey(pk)
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if err != nil {
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return nil, err
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}
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k := ssh.MarshalAuthorizedKey(b)
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return k, nil
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}
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// encodePrivateKeyToPEM encodes the given private key to a PEM block.
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// The encoded format is PKCS#8 for universal support of the most
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// common key types (rsa, ecdsa, ed25519).
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func encodePrivateKeyToPEM(pk interface{}) ([]byte, error) {
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b, err := x509.MarshalPKCS8PrivateKey(pk)
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if err != nil {
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return nil, err
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}
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block := pem.Block{
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Type: "PRIVATE KEY",
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Bytes: b,
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}
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return pem.EncodeToMemory(&block), nil
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}
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446
ssh/knownhosts/knownhosts.go
Normal file
446
ssh/knownhosts/knownhosts.go
Normal file
@@ -0,0 +1,446 @@
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// Copyright 2017 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// Copyright 2020 The FluxCD contributors. All rights reserved.
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// This package provides an in-memory known hosts database
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// derived from the golang.org/x/crypto/ssh/knownhosts
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// package.
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// It has been slightly modified and adapted to work with
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// in-memory host keys not related to any known_hosts files
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// on disk, and the database can be initialized with just a
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// known_hosts byte blob.
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// https://pkg.go.dev/golang.org/x/crypto/ssh/knownhosts
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package knownhosts
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import (
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"bufio"
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"bytes"
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"crypto/hmac"
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"crypto/sha1"
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"encoding/base64"
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"errors"
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"fmt"
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"io"
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"net"
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"strings"
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"golang.org/x/crypto/ssh"
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"golang.org/x/crypto/ssh/knownhosts"
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)
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// See the sshd manpage
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// (http://man.openbsd.org/sshd#SSH_KNOWN_HOSTS_FILE_FORMAT) for
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// background.
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type addr struct{ host, port string }
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func (a *addr) String() string {
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h := a.host
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if strings.Contains(h, ":") {
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h = "[" + h + "]"
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}
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return h + ":" + a.port
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}
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type matcher interface {
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match(addr) bool
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}
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type hostPattern struct {
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negate bool
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addr addr
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}
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func (p *hostPattern) String() string {
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n := ""
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if p.negate {
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n = "!"
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}
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return n + p.addr.String()
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}
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type hostPatterns []hostPattern
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func (ps hostPatterns) match(a addr) bool {
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matched := false
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for _, p := range ps {
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if !p.match(a) {
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continue
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}
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if p.negate {
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return false
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}
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matched = true
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}
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return matched
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}
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// See
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// https://android.googlesource.com/platform/external/openssh/+/ab28f5495c85297e7a597c1ba62e996416da7c7e/addrmatch.c
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// The matching of * has no regard for separators, unlike filesystem globs
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func wildcardMatch(pat []byte, str []byte) bool {
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for {
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if len(pat) == 0 {
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return len(str) == 0
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}
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if len(str) == 0 {
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return false
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}
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if pat[0] == '*' {
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if len(pat) == 1 {
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return true
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}
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for j := range str {
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if wildcardMatch(pat[1:], str[j:]) {
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return true
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}
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}
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return false
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}
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if pat[0] == '?' || pat[0] == str[0] {
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pat = pat[1:]
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str = str[1:]
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} else {
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return false
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}
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}
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}
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func (p *hostPattern) match(a addr) bool {
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return wildcardMatch([]byte(p.addr.host), []byte(a.host)) && p.addr.port == a.port
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}
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type inMemoryHostKeyDB struct {
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hostKeys []hostKey
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revoked map[string]*ssh.PublicKey
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}
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func newInMemoryHostKeyDB() *inMemoryHostKeyDB {
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db := &inMemoryHostKeyDB{
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revoked: make(map[string]*ssh.PublicKey),
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}
|
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|
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return db
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}
|
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|
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func keyEq(a, b ssh.PublicKey) bool {
|
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return bytes.Equal(a.Marshal(), b.Marshal())
|
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}
|
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|
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type hostKey struct {
|
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matcher matcher
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cert bool
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key ssh.PublicKey
|
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}
|
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|
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func (l *hostKey) match(a addr) bool {
|
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return l.matcher.match(a)
|
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}
|
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|
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// IsAuthorityForHost can be used as a callback in ssh.CertChecker
|
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func (db *inMemoryHostKeyDB) IsHostAuthority(remote ssh.PublicKey, address string) bool {
|
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h, p, err := net.SplitHostPort(address)
|
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if err != nil {
|
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return false
|
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}
|
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a := addr{host: h, port: p}
|
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|
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for _, l := range db.hostKeys {
|
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if l.cert && keyEq(l.key, remote) && l.match(a) {
|
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return true
|
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}
|
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}
|
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return false
|
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}
|
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|
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// IsRevoked can be used as a callback in ssh.CertChecker
|
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func (db *inMemoryHostKeyDB) IsRevoked(key *ssh.Certificate) bool {
|
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_, ok := db.revoked[string(key.Marshal())]
|
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return ok
|
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}
|
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|
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const markerCert = "@cert-authority"
|
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const markerRevoked = "@revoked"
|
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|
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func nextWord(line []byte) (string, []byte) {
|
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i := bytes.IndexAny(line, "\t ")
|
||||
if i == -1 {
|
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return string(line), nil
|
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}
|
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|
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return string(line[:i]), bytes.TrimSpace(line[i:])
|
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}
|
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|
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func parseLine(line []byte) (marker, host string, key ssh.PublicKey, err error) {
|
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if w, next := nextWord(line); w == markerCert || w == markerRevoked {
|
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marker = w
|
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line = next
|
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}
|
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|
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host, line = nextWord(line)
|
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if len(line) == 0 {
|
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return "", "", nil, errors.New("knownhosts: missing host pattern")
|
||||
}
|
||||
|
||||
// ignore the keytype as it's in the key blob anyway.
|
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_, line = nextWord(line)
|
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if len(line) == 0 {
|
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return "", "", nil, errors.New("knownhosts: missing key type pattern")
|
||||
}
|
||||
|
||||
keyBlob, _ := nextWord(line)
|
||||
|
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keyBytes, err := base64.StdEncoding.DecodeString(keyBlob)
|
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if err != nil {
|
||||
return "", "", nil, err
|
||||
}
|
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key, err = ssh.ParsePublicKey(keyBytes)
|
||||
if err != nil {
|
||||
return "", "", nil, err
|
||||
}
|
||||
|
||||
return marker, host, key, nil
|
||||
}
|
||||
|
||||
func (db *inMemoryHostKeyDB) parseLine(line []byte) error {
|
||||
marker, pattern, key, err := parseLine(line)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
if marker == markerRevoked {
|
||||
db.revoked[string(key.Marshal())] = &key
|
||||
return nil
|
||||
}
|
||||
|
||||
entry := hostKey{
|
||||
key: key,
|
||||
cert: marker == markerCert,
|
||||
}
|
||||
|
||||
if pattern[0] == '|' {
|
||||
entry.matcher, err = newHashedHost(pattern)
|
||||
} else {
|
||||
entry.matcher, err = newHostnameMatcher(pattern)
|
||||
}
|
||||
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
db.hostKeys = append(db.hostKeys, entry)
|
||||
return nil
|
||||
}
|
||||
|
||||
func newHostnameMatcher(pattern string) (matcher, error) {
|
||||
var hps hostPatterns
|
||||
for _, p := range strings.Split(pattern, ",") {
|
||||
if len(p) == 0 {
|
||||
continue
|
||||
}
|
||||
|
||||
var a addr
|
||||
var negate bool
|
||||
if p[0] == '!' {
|
||||
negate = true
|
||||
p = p[1:]
|
||||
}
|
||||
|
||||
if len(p) == 0 {
|
||||
return nil, errors.New("knownhosts: negation without following hostname")
|
||||
}
|
||||
|
||||
var err error
|
||||
if p[0] == '[' {
|
||||
a.host, a.port, err = net.SplitHostPort(p)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
} else {
|
||||
a.host, a.port, err = net.SplitHostPort(p)
|
||||
if err != nil {
|
||||
a.host = p
|
||||
a.port = "22"
|
||||
}
|
||||
}
|
||||
hps = append(hps, hostPattern{
|
||||
negate: negate,
|
||||
addr: a,
|
||||
})
|
||||
}
|
||||
return hps, nil
|
||||
}
|
||||
|
||||
// check checks a key against the host database. This should not be
|
||||
// used for verifying certificates.
|
||||
func (db *inMemoryHostKeyDB) check(address string, remote net.Addr, remoteKey ssh.PublicKey) error {
|
||||
if revoked := db.revoked[string(remoteKey.Marshal())]; revoked != nil {
|
||||
return &knownhosts.RevokedError{Revoked: knownhosts.KnownKey{Key: *revoked}}
|
||||
}
|
||||
|
||||
host, port, err := net.SplitHostPort(remote.String())
|
||||
if err != nil {
|
||||
return fmt.Errorf("knownhosts: SplitHostPort(%s): %v", remote, err)
|
||||
}
|
||||
|
||||
hostToCheck := addr{host, port}
|
||||
if address != "" {
|
||||
// Give preference to the hostname if available.
|
||||
host, port, err := net.SplitHostPort(address)
|
||||
if err != nil {
|
||||
return fmt.Errorf("knownhosts: SplitHostPort(%s): %v", address, err)
|
||||
}
|
||||
|
||||
hostToCheck = addr{host, port}
|
||||
}
|
||||
|
||||
return db.checkAddr(hostToCheck, remoteKey)
|
||||
}
|
||||
|
||||
// checkAddr checks if we can find the given public key for the
|
||||
// given address. If we only find an entry for the IP address,
|
||||
// or only the hostname, then this still succeeds.
|
||||
func (db *inMemoryHostKeyDB) checkAddr(a addr, remoteKey ssh.PublicKey) error {
|
||||
// TODO(hanwen): are these the right semantics? What if there
|
||||
// is just a key for the IP address, but not for the
|
||||
// hostname?
|
||||
|
||||
// Algorithm => key.
|
||||
knownKeys := map[string]ssh.PublicKey{}
|
||||
for _, l := range db.hostKeys {
|
||||
if l.match(a) {
|
||||
typ := l.key.Type()
|
||||
if _, ok := knownKeys[typ]; !ok {
|
||||
knownKeys[typ] = l.key
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
keyErr := &knownhosts.KeyError{}
|
||||
for _, v := range knownKeys {
|
||||
keyErr.Want = append(keyErr.Want, knownhosts.KnownKey{Key: v})
|
||||
}
|
||||
|
||||
// Unknown remote host.
|
||||
if len(knownKeys) == 0 {
|
||||
return keyErr
|
||||
}
|
||||
|
||||
// If the remote host starts using a different, unknown key type, we
|
||||
// also interpret that as a mismatch.
|
||||
if known, ok := knownKeys[remoteKey.Type()]; !ok || !keyEq(known, remoteKey) {
|
||||
return keyErr
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
// The Read function parses file contents.
|
||||
func (db *inMemoryHostKeyDB) Read(r io.Reader) error {
|
||||
scanner := bufio.NewScanner(r)
|
||||
|
||||
lineNum := 0
|
||||
for scanner.Scan() {
|
||||
lineNum++
|
||||
line := scanner.Bytes()
|
||||
line = bytes.TrimSpace(line)
|
||||
if len(line) == 0 || line[0] == '#' {
|
||||
continue
|
||||
}
|
||||
|
||||
if err := db.parseLine(line); err != nil {
|
||||
return fmt.Errorf("knownhosts: %v", err)
|
||||
}
|
||||
}
|
||||
return scanner.Err()
|
||||
}
|
||||
|
||||
// New creates a host key callback from the given OpenSSH host key
|
||||
// file bytes. The returned callback is for use in
|
||||
// ssh.ClientConfig.HostKeyCallback. By preference, the key check
|
||||
// operates on the hostname if available, i.e. if a server changes its
|
||||
// IP address, the host key check will still succeed, even though a
|
||||
// record of the new IP address is not available.
|
||||
func New(b []byte) (ssh.HostKeyCallback, error) {
|
||||
db := newInMemoryHostKeyDB()
|
||||
r := bytes.NewReader(b)
|
||||
if err := db.Read(r); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
var certChecker ssh.CertChecker
|
||||
certChecker.IsHostAuthority = db.IsHostAuthority
|
||||
certChecker.IsRevoked = db.IsRevoked
|
||||
certChecker.HostKeyFallback = db.check
|
||||
|
||||
return certChecker.CheckHostKey, nil
|
||||
}
|
||||
|
||||
func decodeHash(encoded string) (hashType string, salt, hash []byte, err error) {
|
||||
if len(encoded) == 0 || encoded[0] != '|' {
|
||||
err = errors.New("knownhosts: hashed host must start with '|'")
|
||||
return
|
||||
}
|
||||
components := strings.Split(encoded, "|")
|
||||
if len(components) != 4 {
|
||||
err = fmt.Errorf("knownhosts: got %d components, want 3", len(components))
|
||||
return
|
||||
}
|
||||
|
||||
hashType = components[1]
|
||||
if salt, err = base64.StdEncoding.DecodeString(components[2]); err != nil {
|
||||
return
|
||||
}
|
||||
if hash, err = base64.StdEncoding.DecodeString(components[3]); err != nil {
|
||||
return
|
||||
}
|
||||
return
|
||||
}
|
||||
|
||||
func encodeHash(typ string, salt []byte, hash []byte) string {
|
||||
return strings.Join([]string{"",
|
||||
typ,
|
||||
base64.StdEncoding.EncodeToString(salt),
|
||||
base64.StdEncoding.EncodeToString(hash),
|
||||
}, "|")
|
||||
}
|
||||
|
||||
// See https://android.googlesource.com/platform/external/openssh/+/ab28f5495c85297e7a597c1ba62e996416da7c7e/hostfile.c#120
|
||||
func hashHost(hostname string, salt []byte) []byte {
|
||||
mac := hmac.New(sha1.New, salt)
|
||||
mac.Write([]byte(hostname))
|
||||
return mac.Sum(nil)
|
||||
}
|
||||
|
||||
type hashedHost struct {
|
||||
salt []byte
|
||||
hash []byte
|
||||
}
|
||||
|
||||
const sha1HashType = "1"
|
||||
|
||||
func newHashedHost(encoded string) (*hashedHost, error) {
|
||||
typ, salt, hash, err := decodeHash(encoded)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
// The type field seems for future algorithm agility, but it's
|
||||
// actually hardcoded in openssh currently, see
|
||||
// https://android.googlesource.com/platform/external/openssh/+/ab28f5495c85297e7a597c1ba62e996416da7c7e/hostfile.c#120
|
||||
if typ != sha1HashType {
|
||||
return nil, fmt.Errorf("knownhosts: got hash type %s, must be '1'", typ)
|
||||
}
|
||||
|
||||
return &hashedHost{salt: salt, hash: hash}, nil
|
||||
}
|
||||
|
||||
func (h *hashedHost) match(a addr) bool {
|
||||
return bytes.Equal(hashHost(knownhosts.Normalize(a.String()), h.salt), h.hash)
|
||||
}
|
||||
327
ssh/knownhosts/knownhosts_test.go
Normal file
327
ssh/knownhosts/knownhosts_test.go
Normal file
@@ -0,0 +1,327 @@
|
||||
// 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.
|
||||
|
||||
// Copyright 2020 The FluxCD contributors. All rights reserved.
|
||||
// This package provides an in-memory known hosts database
|
||||
// derived from the golang.org/x/crypto/ssh/knownhosts
|
||||
// package.
|
||||
// It has been slightly modified and adapted to work with
|
||||
// in-memory host keys not related to any known_hosts files
|
||||
// on disk, and the database can be initialized with just a
|
||||
// known_hosts byte blob.
|
||||
// https://pkg.go.dev/golang.org/x/crypto/ssh/knownhosts
|
||||
|
||||
package knownhosts
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"fmt"
|
||||
"net"
|
||||
"reflect"
|
||||
"testing"
|
||||
|
||||
"golang.org/x/crypto/ssh"
|
||||
"golang.org/x/crypto/ssh/knownhosts"
|
||||
)
|
||||
|
||||
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) *inMemoryHostKeyDB {
|
||||
db := newInMemoryHostKeyDB()
|
||||
if err := db.Read(bytes.NewBufferString(s)); err != nil {
|
||||
t.Fatalf("Read: %v", err)
|
||||
}
|
||||
|
||||
return db
|
||||
}
|
||||
|
||||
func TestRevoked(t *testing.T) {
|
||||
db := testDB(t, "\n\n@revoked * "+edKeyStr+"\n")
|
||||
want := &knownhosts.RevokedError{
|
||||
Revoked: knownhosts.KnownKey{
|
||||
Key: edKey,
|
||||
},
|
||||
}
|
||||
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.hostKeys[0].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.(*knownhosts.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.(*knownhosts.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.(*knownhosts.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 := knownhosts.KnownKey{
|
||||
Key: edKey,
|
||||
}
|
||||
if err := db.check("server.org:22", testAddr, ecKey); err == nil {
|
||||
t.Errorf("succeeded, want KeyError")
|
||||
} else if ke, ok := err.(*knownhosts.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.(*knownhosts.KeyError); !ok {
|
||||
t.Errorf("got %T, want *KeyError", err)
|
||||
}
|
||||
}
|
||||
|
||||
func TestDBOrderingPrecedenceKeyType(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, alternateEdKey); err == nil {
|
||||
t.Errorf("check succeeded")
|
||||
} else if _, ok := err.(*knownhosts.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.(*knownhosts.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 := &knownhosts.KeyError{
|
||||
Want: []knownhosts.KnownKey{{
|
||||
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 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 := knownhosts.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 TestHashedHostkeyCheck(t *testing.T) {
|
||||
str := fmt.Sprintf("%s %s", knownhosts.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 := &knownhosts.KeyError{
|
||||
Want: []knownhosts.KnownKey{{
|
||||
Key: edKey,
|
||||
}},
|
||||
}
|
||||
if got := db.check(testHostname+":22", testAddr, alternateEdKey); !reflect.DeepEqual(got, want) {
|
||||
t.Errorf("got error %v, want %v", got, want)
|
||||
}
|
||||
}
|
||||
Reference in New Issue
Block a user