-
Notifications
You must be signed in to change notification settings - Fork 4.3k
/
utils.go
164 lines (150 loc) · 4.61 KB
/
utils.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
151
152
153
154
155
156
157
158
159
160
161
162
163
164
/*
*
* Copyright 2018 gRPC 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 alts
import (
"context"
"errors"
"fmt"
"io"
"io/ioutil"
"log"
"os"
"os/exec"
"regexp"
"runtime"
"strings"
"google.golang.org/grpc/codes"
"google.golang.org/grpc/peer"
"google.golang.org/grpc/status"
)
const (
linuxProductNameFile = "/sys/class/dmi/id/product_name"
windowsCheckCommand = "powershell.exe"
windowsCheckCommandArgs = "Get-WmiObject -Class Win32_BIOS"
powershellOutputFilter = "Manufacturer"
windowsManufacturerRegex = ":(.*)"
)
type platformError string
func (k platformError) Error() string {
return fmt.Sprintf("%s is not supported", string(k))
}
var (
// The following two variables will be reassigned in tests.
runningOS = runtime.GOOS
manufacturerReader = func() (io.Reader, error) {
switch runningOS {
case "linux":
return os.Open(linuxProductNameFile)
case "windows":
cmd := exec.Command(windowsCheckCommand, windowsCheckCommandArgs)
out, err := cmd.Output()
if err != nil {
return nil, err
}
for _, line := range strings.Split(strings.TrimSuffix(string(out), "\n"), "\n") {
if strings.HasPrefix(line, powershellOutputFilter) {
re := regexp.MustCompile(windowsManufacturerRegex)
name := re.FindString(line)
name = strings.TrimLeft(name, ":")
return strings.NewReader(name), nil
}
}
return nil, errors.New("cannot determine the machine's manufacturer")
default:
return nil, platformError(runningOS)
}
}
vmOnGCP bool
)
// isRunningOnGCP checks whether the local system, without doing a network request is
// running on GCP.
func isRunningOnGCP() bool {
manufacturer, err := readManufacturer()
if os.IsNotExist(err) {
return false
}
if err != nil {
log.Fatalf("failure to read manufacturer information: %v", err)
}
name := string(manufacturer)
switch runningOS {
case "linux":
name = strings.TrimSpace(name)
return name == "Google" || name == "Google Compute Engine"
case "windows":
name = strings.Replace(name, " ", "", -1)
name = strings.Replace(name, "\n", "", -1)
name = strings.Replace(name, "\r", "", -1)
return name == "Google"
default:
log.Fatal(platformError(runningOS))
}
return false
}
func readManufacturer() ([]byte, error) {
reader, err := manufacturerReader()
if err != nil {
return nil, err
}
if reader == nil {
return nil, errors.New("got nil reader")
}
manufacturer, err := ioutil.ReadAll(reader)
if err != nil {
return nil, fmt.Errorf("failed reading %v: %v", linuxProductNameFile, err)
}
return manufacturer, nil
}
// AuthInfoFromContext extracts the alts.AuthInfo object from the given context,
// if it exists. This API should be used by gRPC server RPC handlers to get
// information about the communicating peer. For client-side, use grpc.Peer()
// CallOption.
func AuthInfoFromContext(ctx context.Context) (AuthInfo, error) {
p, ok := peer.FromContext(ctx)
if !ok {
return nil, errors.New("no Peer found in Context")
}
return AuthInfoFromPeer(p)
}
// AuthInfoFromPeer extracts the alts.AuthInfo object from the given peer, if it
// exists. This API should be used by gRPC clients after obtaining a peer object
// using the grpc.Peer() CallOption.
func AuthInfoFromPeer(p *peer.Peer) (AuthInfo, error) {
altsAuthInfo, ok := p.AuthInfo.(AuthInfo)
if !ok {
return nil, errors.New("no alts.AuthInfo found in Peer")
}
return altsAuthInfo, nil
}
// ClientAuthorizationCheck checks whether the client is authorized to access
// the requested resources based on the given expected client service accounts.
// This API should be used by gRPC server RPC handlers. This API should not be
// used by clients.
func ClientAuthorizationCheck(ctx context.Context, expectedServiceAccounts []string) error {
authInfo, err := AuthInfoFromContext(ctx)
if err != nil {
return status.Errorf(codes.PermissionDenied, "The context is not an ALTS-compatible context: %v", err)
}
peer := authInfo.PeerServiceAccount()
for _, sa := range expectedServiceAccounts {
if strings.EqualFold(peer, sa) {
return nil
}
}
return status.Errorf(codes.PermissionDenied, "Client %v is not authorized", peer)
}