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
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
|
package main
import (
"context"
"fmt"
"io"
"io/ioutil"
"log"
"net"
"net/http"
"os"
"git.deuxfleurs.fr/Deuxfleurs/bagage/s3"
"git.deuxfleurs.fr/Deuxfleurs/bagage/sftp"
"github.com/minio/minio-go/v7"
"github.com/minio/minio-go/v7/pkg/credentials"
"golang.org/x/crypto/ssh"
)
func main() {
log.Println("=== Starting Bagage ===")
config := (&Config{}).LoadWithDefault().LoadWithEnv()
log.Println(config)
// Some init
err := os.MkdirAll(config.S3Cache, 0755)
if err != nil {
log.Fatalf("init failed: mkdir s3 cache failed: ", err)
}
// Launch our submodules
done := make(chan error)
go httpServer(config, done)
go sshServer(config, done)
err = <-done
if err != nil {
log.Fatalf("A component failed: %v", err)
}
}
type s3creds struct {
accessKey string
secretKey string
}
var keychain map[string]s3creds
func sshServer(dconfig *Config, done chan error) {
keychain = make(map[string]s3creds)
config := &ssh.ServerConfig{
PasswordCallback: func(c ssh.ConnMetadata, pass []byte) (*ssh.Permissions, error) {
log.Printf("Login: %s\n", c.User())
access_key, secret_key, err := LdapGetS3(dconfig, c.User(), string(pass))
if err == nil {
keychain[c.User()] = s3creds{access_key, secret_key}
}
return nil, err
},
}
privateBytes, err := ioutil.ReadFile(dconfig.SSHKey)
if err != nil {
log.Fatal("Failed to load private key", err)
}
private, err := ssh.ParsePrivateKey(privateBytes)
if err != nil {
log.Fatal("Failed to parse private key", err)
}
config.AddHostKey(private)
// Once a ServerConfig has been configured, connections can be
// accepted.
listener, err := net.Listen("tcp", "0.0.0.0:2222")
if err != nil {
log.Fatal("failed to listen for connection", err)
}
log.Printf("Listening on %v\n", listener.Addr())
for {
nConn, err := listener.Accept()
if err != nil {
log.Printf("failed to accept incoming connection: ", err)
continue
}
go handleSSHConn(nConn, dconfig, config)
}
}
func handleSSHConn(nConn net.Conn, dconfig *Config, config *ssh.ServerConfig) {
ctx, cancel := context.WithCancel(context.Background())
defer cancel()
defer nConn.Close()
// Before use, a handshake must be performed on the incoming
// net.Conn.
serverConn, chans, reqs, err := ssh.NewServerConn(nConn, config)
if err != nil {
log.Printf("failed to handshake: ", err)
return
}
defer serverConn.Conn.Close()
user := serverConn.Conn.User()
log.Printf("SSH connection established for %v\n", user)
// The incoming Request channel must be serviced.
go ssh.DiscardRequests(reqs)
// Service the incoming Channel channel.
for newChannel := range chans {
// Channels have a type, depending on the application level
// protocol intended. In the case of an SFTP session, this is "subsystem"
// with a payload string of "<length=4>sftp"
log.Printf("Incoming channel: %s\n", newChannel.ChannelType())
if newChannel.ChannelType() != "session" {
newChannel.Reject(ssh.UnknownChannelType, "unknown channel type")
log.Printf("Unknown channel type: %s\n", newChannel.ChannelType())
continue
}
channel, requests, err := newChannel.Accept()
if err != nil {
log.Print("could not accept channel.", err)
return
}
log.Printf("Channel accepted\n")
// Sessions have out-of-band requests such as "shell",
// "pty-req" and "env". Here we handle only the
// "subsystem" request.
go func(in <-chan *ssh.Request) {
for req := range in {
log.Printf("Request: %v\n", req.Type)
ok := false
switch req.Type {
case "subsystem":
log.Printf("Subsystem: %s\n", req.Payload[4:])
if string(req.Payload[4:]) == "sftp" {
ok = true
}
}
log.Printf(" - accepted: %v\n", ok)
req.Reply(ok, nil)
}
}(requests)
creds := keychain[user]
mc, err := minio.New(dconfig.Endpoint, &minio.Options{
Creds: credentials.NewStaticV4(creds.accessKey, creds.secretKey, ""),
Secure: dconfig.UseSSL,
})
if err != nil {
return
}
fs := s3.NewS3FS(mc, dconfig.S3Cache)
server, err := sftp.NewServer(ctx, channel, &fs)
if err != nil {
log.Println(err)
return
}
if err := server.Serve(); err == io.EOF {
server.Close()
log.Print("sftp client exited session.")
} else if err != nil {
log.Print("sftp server completed with error:", err)
}
}
}
func httpServer(config *Config, done chan error) {
// Assemble components to handle WebDAV requests
http.Handle(config.DavPath+"/",
CorsAllowAllOrigins{
AndThen: BasicAuthExtract{
OnNotFound: OptionsNoError{
NotAuthorized{},
},
OnCreds: LdapPreAuth{
WithConfig: config,
OnWrongPassword: OptionsNoError{
Error: NotAuthorized{},
},
OnFailure: InternalError{},
OnCreds: S3Auth{
WithConfig: config,
OnFailure: InternalError{},
OnMinioClient: WebDav{
WithConfig: config,
},
},
},
},
})
if err := http.ListenAndServe(config.HttpListen, nil); err != nil {
done <- fmt.Errorf("Error with WebDAV server: %v", err)
} else {
done <- nil
}
}
|
