forked from kubernetes/kubernetes
-
Notifications
You must be signed in to change notification settings - Fork 0
/
check_metadata_concealment.go
150 lines (141 loc) · 5.3 KB
/
check_metadata_concealment.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
/*
Copyright 2017 The Kubernetes Authors.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package main
import (
"fmt"
"io/ioutil"
"log"
"net/http"
"os"
"regexp"
)
var (
successEndpoints = []string{
// Discovery
"http://169.254.169.254",
"http://metadata.google.internal",
"http://169.254.169.254/",
"http://metadata.google.internal/",
"http://metadata.google.internal/0.1",
"http://metadata.google.internal/0.1/",
"http://metadata.google.internal/0.1/meta-data",
"http://metadata.google.internal/computeMetadata",
"http://metadata.google.internal/computeMetadata/v1beta1",
"http://metadata.google.internal/computeMetadata/v1",
// Allowed API versions.
"http://metadata.google.internal/0.1/meta-data/",
"http://metadata.google.internal/computeMetadata/v1beta1/",
"http://metadata.google.internal/computeMetadata/v1/",
// Service account token endpoints.
"http://metadata.google.internal/0.1/meta-data/service-accounts/default/acquire",
"http://metadata.google.internal/computeMetadata/v1beta1/instance/service-accounts/default/token",
"http://metadata.google.internal/computeMetadata/v1/instance/service-accounts/default/token",
// Params that contain 'recursive' as substring.
"http://metadata.google.internal/computeMetadata/v1/instance/?nonrecursive=true",
"http://metadata.google.internal/computeMetadata/v1/instance/?something=other&nonrecursive=true",
}
noKubeEnvEndpoints = []string{
// Check that these don't get a recursive result.
"http://metadata.google.internal/computeMetadata/v1/instance/?recursive%3Dtrue", // urlencoded
"http://metadata.google.internal/computeMetadata/v1/instance/?re%08ecursive=true", // backspaced
}
failureEndpoints = []string{
// Other API versions.
"http://metadata.google.internal/0.2/",
"http://metadata.google.internal/computeMetadata/v2/",
// kube-env.
"http://metadata.google.internal/0.1/meta-data/attributes/kube-env",
"http://metadata.google.internal/computeMetadata/v1beta1/instance/attributes/kube-env",
"http://metadata.google.internal/computeMetadata/v1/instance/attributes/kube-env",
// VM identity.
"http://metadata.google.internal/0.1/meta-data/service-accounts/default/identity",
"http://metadata.google.internal/computeMetadata/v1beta1/instance/service-accounts/default/identity",
"http://metadata.google.internal/computeMetadata/v1/instance/service-accounts/default/identity",
// Recursive.
"http://metadata.google.internal/computeMetadata/v1/instance/?recursive=true",
"http://metadata.google.internal/computeMetadata/v1/instance/?something=other&recursive=true",
"http://metadata.google.internal/computeMetadata/v1/instance/?recursive=true&something=other",
// Other.
"http://metadata.google.internal/computeMetadata/v1/instance/attributes//kube-env",
"http://metadata.google.internal/computeMetadata/v1/instance/attributes/../attributes/kube-env",
"http://metadata.google.internal/computeMetadata/v1/instance/service-accounts//default/identity",
"http://metadata.google.internal/computeMetadata/v1/instance/service-accounts/../service-accounts/default/identity",
}
)
func main() {
success := 0
h := map[string][]string{
"Metadata-Flavor": {"Google"},
}
for _, e := range successEndpoints {
if err := checkURL(e, h, 200, ""); err != nil {
log.Printf("Wrong response for %v: %v", e, err)
success = 1
}
}
for _, e := range noKubeEnvEndpoints {
if err := checkURL(e, h, 200, "kube-env"); err != nil {
log.Printf("Wrong response for %v: %v", e, err)
success = 1
}
}
for _, e := range failureEndpoints {
if err := checkURL(e, h, 403, ""); err != nil {
log.Printf("Wrong response for %v: %v", e, err)
success = 1
}
}
xForwardedForHeader := map[string][]string{
"X-Forwarded-For": {"Somebody-somewhere"},
}
// Check that success endpoints fail if X-Forwarded-For is present.
for _, e := range successEndpoints {
if err := checkURL(e, xForwardedForHeader, 403, ""); err != nil {
log.Printf("Wrong response for %v with X-Forwarded-For: %v", e, err)
success = 1
}
}
os.Exit(success)
}
// Checks that a URL with the given headers returns the right code, and if s is
// non-empty, checks that the body doesn't contain s.
func checkURL(url string, header http.Header, expectedStatus int, s string) error {
client := &http.Client{}
req, err := http.NewRequest("GET", url, nil)
if err != nil {
return err
}
req.Header = header
resp, err := client.Do(req)
if err != nil {
return err
}
defer resp.Body.Close()
if resp.StatusCode != expectedStatus {
return fmt.Errorf("unexpected response: got %d, want %d", resp.StatusCode, expectedStatus)
}
body, err := ioutil.ReadAll(resp.Body)
if err != nil {
return err
}
if s != "" {
matched, err := regexp.Match(s, body)
if err != nil {
return err
}
if matched {
return fmt.Errorf("body incorrectly contained %q: got %v", s, string(body))
}
}
return nil
}