-
Notifications
You must be signed in to change notification settings - Fork 55
/
recv.go
403 lines (341 loc) · 9.54 KB
/
recv.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
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
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
package wormhole
import (
"context"
"crypto/sha256"
"encoding/hex"
"encoding/json"
"errors"
"fmt"
"hash"
"io"
"strings"
"github.com/psanford/wormhole-william/internal/crypto"
"github.com/psanford/wormhole-william/rendezvous"
)
// Receive receives a message sent by a wormhole client.
//
// It returns an IncomingMessage with metadata about the payload being sent.
// To read the contents of the message call IncomingMessage.Read().
func (c *Client) Receive(ctx context.Context, code string) (fr *IncomingMessage, returnErr error) {
sideID := crypto.RandSideID()
appID := c.appID()
rc := rendezvous.NewClient(c.url(), sideID, appID)
defer func() {
mood := rendezvous.Errory
if returnErr == nil {
// don't close our connection in this case
// wait until the user actually accepts the transfer
return
} else if returnErr == errDecryptFailed {
mood = rendezvous.Scary
}
rc.Close(ctx, mood)
}()
_, err := rc.Connect(ctx)
if err != nil {
return nil, err
}
nameplate, err := nameplateFromCode(code)
if err != nil {
return nil, err
}
err = rc.AttachMailbox(ctx, nameplate)
if err != nil {
return nil, err
}
clientProto := newClientProtocol(ctx, rc, sideID, appID)
err = clientProto.WritePake(ctx, code)
if err != nil {
return nil, err
}
err = clientProto.ReadPake(ctx)
if err != nil {
return nil, err
}
err = clientProto.WriteVersion(ctx)
if err != nil {
return nil, err
}
_, err = clientProto.ReadVersion()
if err != nil {
return nil, err
}
if c.VerifierOk != nil {
verifier, err := clientProto.Verifier()
if err != nil {
return nil, err
}
if ok := c.VerifierOk(hex.EncodeToString(verifier)); !ok {
errMsg := "sender rejected verification check, abandoned transfer"
writeErr := clientProto.WriteAppData(ctx, &genericMessage{
Error: &errMsg,
})
if writeErr != nil {
return nil, writeErr
}
return nil, errors.New(errMsg)
}
}
collector, err := clientProto.Collect(collectOffer, collectTransit)
if err != nil {
return nil, err
}
defer collector.close()
var offer offerMsg
err = collector.waitFor(&offer)
if err != nil {
return nil, err
}
fr = &IncomingMessage{}
if offer.Message != nil {
answer := genericMessage{
Answer: &answerMsg{
MessageAck: "ok",
},
}
err = clientProto.WriteAppData(ctx, &answer)
if err != nil {
return nil, err
}
rc.Close(ctx, rendezvous.Happy)
text := *offer.Message
fr.TransferBytes = len(text)
fr.TransferBytes64 = int64(fr.TransferBytes)
fr.UncompressedBytes = fr.TransferBytes
fr.UncompressedBytes64 = fr.TransferBytes64
fr.Type = TransferText
fr.textReader = strings.NewReader(text)
return fr, nil
} else if offer.File != nil {
fr.Type = TransferFile
fr.Name = offer.File.FileName
fr.TransferBytes = int(offer.File.FileSize)
fr.TransferBytes64 = offer.File.FileSize
fr.UncompressedBytes = int(offer.File.FileSize)
fr.UncompressedBytes64 = offer.File.FileSize
fr.FileCount = 1
fr.ctx = ctx
} else if offer.Directory != nil {
fr.Type = TransferDirectory
fr.Name = offer.Directory.Dirname
fr.TransferBytes = int(offer.Directory.ZipSize)
fr.TransferBytes64 = offer.Directory.ZipSize
fr.UncompressedBytes = int(offer.Directory.NumBytes)
fr.UncompressedBytes64 = offer.Directory.NumBytes
fr.FileCount = int(offer.Directory.NumFiles)
fr.ctx = ctx
} else {
return nil, errors.New("got non-file transfer offer")
}
var gotTransitMsg transitMsg
err = collector.waitFor(&gotTransitMsg)
if err != nil {
return nil, err
}
transitKey := deriveTransitKey(clientProto.sharedKey, appID)
transport := newFileTransport(transitKey, appID, c.relayAddr())
transitMsg, err := transport.makeTransitMsg()
if err != nil {
return nil, fmt.Errorf("make transit msg error: %s", err)
}
err = clientProto.WriteAppData(ctx, &genericMessage{
Transit: transitMsg,
})
if err != nil {
return nil, err
}
reject := func() (initErr error) {
defer func() {
mood := rendezvous.Errory
if returnErr == nil {
mood = rendezvous.Happy
} else if returnErr == errDecryptFailed {
mood = rendezvous.Scary
}
rc.Close(ctx, mood)
}()
var errStr = "transfer rejected"
answer := &genericMessage{
Error: &errStr,
}
ctx := context.Background()
err = clientProto.WriteAppData(ctx, answer)
if err != nil {
return err
}
return nil
}
// defer actually sending the "ok" message until
// the caller does a read on the IncomingMessage object.
acceptAndInitialize := func() (initErr error) {
defer func() {
mood := rendezvous.Errory
if returnErr == nil {
mood = rendezvous.Happy
} else if returnErr == errDecryptFailed {
mood = rendezvous.Scary
}
rc.Close(ctx, mood)
}()
answer := &genericMessage{
Answer: &answerMsg{
FileAck: "ok",
},
}
ctx := context.Background()
err = clientProto.WriteAppData(ctx, answer)
if err != nil {
return err
}
conn, err := transport.connectDirect(&gotTransitMsg)
if err != nil {
return err
}
if conn == nil {
conn, err = transport.connectViaRelay(&gotTransitMsg)
if err != nil {
return err
}
}
if conn == nil {
return errors.New("failed to establish connection")
}
cryptor := newTransportCryptor(conn, transitKey, "transit_record_sender_key", "transit_record_receiver_key")
fr.cryptor = cryptor
fr.sha256 = sha256.New()
return nil
}
fr.initializeTransfer = acceptAndInitialize
fr.rejectTransfer = reject
return fr, nil
}
// A IncomingMessage contains information about a payload sent to this wormhole client.
//
// The Type field indicates if the sender sent a single file or a directory.
// If the Type is TransferDirectory then reading from the IncomingMessage will
// read a zip file of the contents of the directory.
type IncomingMessage struct {
// Name is the name of the file or directory being transferred.
Name string
// The type of file transfer being offered.
Type TransferType
// Deprecated: TransferBytes has been replaced with with TransferBytes64
// to allow transfer of >2 GiB files on 32 bit systems
TransferBytes int
// TransferBytes64 is the offered size of the file transfer from the peer.
// This is expected to be the number of bytes sent over the network to
// perform the file transfer, however a malicious client could lie about this.
// The primary purpose of this field is to allow the user to choose to accept
// or reject the transfer if the file size is unexpected.
//
// For client implementation convenience, TransferBytes64 is also set for text messages.
// Note that the message has already been fully transferred by the time this value is known.
TransferBytes64 int64
// Deprecated: UncompressedBytes has been replaced with UncompressedBytes64
// to allow transfers of > 2 GiB files on 32 bit systems
UncompressedBytes int
// UncompressedBytes64 is the offered size of the files on disk post decompression.
// This is sent from the peer as part of the offer and a malicious peer could lie
// about this.
// The primary purpose of this field is to allow the user to choose to accept
// or reject the transfer if the file size is unexpected.
//
// For client implementation convenience, UncompressedBytes64 is also set for text messages.
// Note that the message has already been fully transferred by the time this value is known.
UncompressedBytes64 int64
// FileCount is the number of files in a TransferDirectory offer. This is sent
// as part of the offer from the peer and a malicious peer could lie about this.
FileCount int
textReader io.Reader
transferInitialized bool
initializeTransfer func() error
rejectTransfer func() error
cryptor *transportCryptor
buf []byte
readCount int64
sha256 hash.Hash
readErr error
ctx context.Context
}
// Read the decrypted contents sent to this client.
func (f *IncomingMessage) Read(p []byte) (int, error) {
if f.readErr != nil {
return 0, f.readErr
}
switch f.Type {
case TransferText:
return f.readText(p)
case TransferFile, TransferDirectory:
return f.readCrypt(p)
default:
return 0, fmt.Errorf("unknown Receiver type %d", f.Type)
}
}
func (f *IncomingMessage) readText(p []byte) (int, error) {
return f.textReader.Read(p)
}
// Reject an incoming file or directory transfer. This must be
// called before any calls to Read. This does nothing for
// text message transfers.
func (f *IncomingMessage) Reject() error {
switch f.Type {
case TransferFile, TransferDirectory:
default:
return errors.New("can only reject File and Directory transfers")
}
if f.readErr != nil {
return f.readErr
}
if f.transferInitialized {
return errors.New("cannot Reject after calls to Read")
}
f.transferInitialized = true
f.rejectTransfer()
return nil
}
func (f *IncomingMessage) readCrypt(p []byte) (int, error) {
if f.readErr != nil {
return 0, f.readErr
}
if err := f.ctx.Err(); err != nil {
f.readErr = err
if f.cryptor != nil {
f.cryptor.Close()
}
return 0, err
}
if !f.transferInitialized {
f.transferInitialized = true
err := f.initializeTransfer()
if err != nil {
return 0, err
}
}
if len(f.buf) == 0 {
rec, err := f.cryptor.readRecord()
if err == io.EOF {
f.readErr = io.ErrUnexpectedEOF
return 0, f.readErr
} else if err != nil {
f.readErr = err
return 0, err
}
f.buf = rec
}
n := copy(p, f.buf)
f.buf = f.buf[n:]
f.readCount += int64(n)
f.sha256.Write(p[:n])
if f.readCount >= f.TransferBytes64 {
f.readErr = io.EOF
sum := f.sha256.Sum(nil)
ack := fileTransportAck{
Ack: "ok",
SHA256: fmt.Sprintf("%x", sum),
}
msg, _ := json.Marshal(ack)
f.cryptor.writeRecord(msg)
f.cryptor.Close()
}
return n, nil
}