/
autodiscover.go
439 lines (388 loc) · 14.6 KB
/
autodiscover.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
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
package autodiscover
import (
"bytes"
"crypto/tls"
"fmt"
"io/ioutil"
"net"
"net/http"
"net/url"
"os"
"regexp"
"strings"
"text/template"
"github.com/sensepost/ruler/http-ntlm"
"github.com/sensepost/ruler/utils"
)
//globals
//SessionConfig holds the configuration for this autodiscover session
var SessionConfig *utils.Session
var autodiscoverStep int
var secondaryEmail string //a secondary email to use, edge case seen in office365
//the xml for the autodiscover service
const autodiscoverXML = `<?xml version="1.0" encoding="utf-8"?><Autodiscover xmlns="http://schemas.microsoft.com/exchange/autodiscover/outlook/requestschema/2006">
<Request><EMailAddress>{{.Email}}</EMailAddress>
<AcceptableResponseSchema>http://schemas.microsoft.com/exchange/autodiscover/outlook/responseschema/2006a</AcceptableResponseSchema>
</Request></Autodiscover>`
func parseTemplate(tmpl string) (string, error) {
t := template.Must(template.New("tmpl").Parse(tmpl))
var buff bytes.Buffer
err := t.Execute(&buff, SessionConfig)
if err != nil {
return "", err
}
return buff.String(), nil
}
//createAutodiscover generates a domain name of the format autodiscover.domain.com
//and checks if a DNS entry exists for it. If it doesn't it tries DNS for just the domain name.
//returns an empty string if no valid domain was found.
//returns the full (expected) autodiscover URL
func createAutodiscover(domain string, https bool) string {
_, err := net.LookupHost(domain)
if err != nil {
return ""
}
if https == true {
return fmt.Sprintf("https://%s/autodiscover/autodiscover.xml", domain)
}
return fmt.Sprintf("http://%s/autodiscover/autodiscover.xml", domain)
}
//GetMapiHTTP gets the details for MAPI/HTTP
func GetMapiHTTP(email, autoURLPtr string, resp *utils.AutodiscoverResp) (*utils.AutodiscoverResp, string, error) {
//var resp *utils.AutodiscoverResp
var err error
var rawAutodiscover string
if autoURLPtr == "" && resp == nil {
utils.Info.Println("Retrieving MAPI/HTTP info")
//rather use the email address's domain here and --domain is the authentication domain
lastBin := strings.LastIndex(email, "@")
if lastBin == -1 {
return nil, "", fmt.Errorf("The supplied email address seems to be incorrect.\n%s", err)
}
maildomain := email[lastBin+1:]
resp, rawAutodiscover, err = MAPIDiscover(maildomain)
} else if resp == nil {
resp, rawAutodiscover, err = MAPIDiscover(autoURLPtr)
}
if resp == nil || err != nil {
return nil, "", fmt.Errorf("The autodiscover service request did not complete.\n%s", err)
}
//check if the autodiscover service responded with an error
if resp.Response.Error != (utils.AutoError{}) {
return nil, "", fmt.Errorf("The autodiscover service responded with an error.\n%s", resp.Response.Error.Message)
}
return resp, rawAutodiscover, nil
}
//GetRPCHTTP exports the RPC details for RPC/HTTP
func GetRPCHTTP(email, autoURLPtr string, resp *utils.AutodiscoverResp) (*utils.AutodiscoverResp, string, string, string, bool, error) {
//var resp *utils.AutodiscoverResp
var err error
var rawAutodiscover string
if autoURLPtr == "" && resp == nil {
utils.Info.Println("Retrieving RPC/HTTP info")
//rather use the email address's domain here and --domain is the authentication domain
lastBin := strings.LastIndex(email, "@")
if lastBin == -1 {
return nil, "", "", "", false, fmt.Errorf("The supplied email address seems to be incorrect.\n%s", err)
}
maildomain := email[lastBin+1:]
resp, rawAutodiscover, err = Autodiscover(maildomain)
} else if resp == nil {
resp, rawAutodiscover, err = Autodiscover(autoURLPtr)
}
if resp == nil || err != nil {
return nil, "", "", "", false, fmt.Errorf("The autodiscover service request did not complete.\n%s", err)
}
//check if the autodiscover service responded with an error
if resp.Response.Error != (utils.AutoError{}) {
return nil, "", "", "", false, fmt.Errorf("The autodiscover service responded with an error.\n%s", resp.Response.Error.Message)
}
url := ""
user := ""
ntlmAuth := false
for _, v := range resp.Response.Account.Protocol {
if v.Type == "EXPR" {
if v.SSL == "Off" {
url = "http://" + v.Server
} else {
url = "https://" + v.Server
}
if v.AuthPackage == "Ntlm" { //set the encryption on if the server specifies NTLM auth
ntlmAuth = true
}
}
if v.Type == "EXCH" {
user = v.Server
}
}
//possibly office365 with forced RPC/HTTP
if user == "" {
if resp.Response.Account.MicrosoftOnline == true {
lindex := strings.LastIndex(resp.Response.Account.Protocol[0].MailStore.ExternalUrl, "=")
user = resp.Response.Account.Protocol[0].MailStore.ExternalUrl[lindex+1:]
url = "https://outlook.office365.com"
}
}
RPCURL := fmt.Sprintf("%s/rpc/rpcproxy.dll?%s:6001", url, user)
utils.Trace.Printf("RPC URL set: %s\n", RPCURL)
return resp, rawAutodiscover, RPCURL, user, ntlmAuth, nil
}
//CheckCache checks to see if there is a stored copy of the autodiscover record
func CheckCache(email string) *utils.AutodiscoverResp {
//check the cache folder for a stored autodiscover record
email = strings.Replace(email, "@", "_", -1)
email = strings.Replace(email, ".", "_", -1)
path := fmt.Sprintf("./logs/%s.cache", email)
if _, err := os.Stat(path); err != nil {
if os.IsNotExist(err) {
return nil
}
utils.Error.Println(err)
return nil
}
utils.Info.Println("Found cached Autodiscover record. Using this (use --nocache to force new lookup)")
data, err := ioutil.ReadFile(path)
if err != nil {
utils.Error.Println("Error reading stored record ", err)
return nil
}
autodiscoverResp := utils.AutodiscoverResp{}
autodiscoverResp.Unmarshal(data)
return &autodiscoverResp
}
//CreateCache function stores the raw autodiscover record to file
func CreateCache(email, autodiscover string) {
if autodiscover == "" { //no autodiscover record passed in, don't try write
return
}
email = strings.Replace(email, "@", "_", -1)
email = strings.Replace(email, ".", "_", -1)
path := fmt.Sprintf("./logs/%s.cache", email)
if _, err := os.Stat("./logs"); err != nil {
if os.IsNotExist(err) {
//create the logs directory
if err := os.MkdirAll("./logs", 0711); err != nil {
utils.Error.Println("Couldn't create a cache directory")
}
//return nil
}
}
fout, _ := os.OpenFile(path, os.O_CREATE|os.O_WRONLY, 0666)
_, err := fout.WriteString(autodiscover)
if err != nil {
utils.Error.Println("Couldn't write to file for some reason..", err)
}
}
//Autodiscover function to retrieve mailbox details using the autodiscover mechanism from MS Exchange
func Autodiscover(domain string) (*utils.AutodiscoverResp, string, error) {
return autodiscover(domain, false)
}
//MAPIDiscover function to do the autodiscover request but specify the MAPI header
//indicating that the MAPI end-points should be returned
func MAPIDiscover(domain string) (*utils.AutodiscoverResp, string, error) {
//fmt.Println("Doing Autodiscover for domain")
return autodiscover(domain, true)
}
func autodiscover(domain string, mapi bool) (*utils.AutodiscoverResp, string, error) {
//replace Email with the email from the config
r, _ := parseTemplate(autodiscoverXML)
autodiscoverResp := utils.AutodiscoverResp{}
//for now let's rely on autodiscover.domain/autodiscover/autodiscover.xml
//var client http.Client
client := http.Client{Transport: &http.Transport{
TLSClientConfig: &tls.Config{InsecureSkipVerify: SessionConfig.Insecure},
}}
if SessionConfig.Basic == false {
//check if this is a first request or a redirect
//create an ntml http client
client = http.Client{
Transport: &httpntlm.NtlmTransport{
Domain: SessionConfig.Domain,
User: SessionConfig.User,
Password: SessionConfig.Pass,
NTHash: SessionConfig.NTHash,
Insecure: SessionConfig.Insecure,
CookieJar: SessionConfig.CookieJar,
},
Jar: SessionConfig.CookieJar,
}
}
var autodiscoverURL string
//check if this is just a domain, a redirect or a url (starts with http[s]://)
if m, _ := regexp.Match("http[s]?://", []byte(domain)); m == true {
autodiscoverURL = domain
} else {
//create the autodiscover url
if autodiscoverStep == 0 {
autodiscoverURL = createAutodiscover(domain, true)
if autodiscoverURL == "" {
autodiscoverStep++
}
}
if autodiscoverStep == 1 {
autodiscoverURL = createAutodiscover(fmt.Sprintf("autodiscover.%s", domain), true)
if autodiscoverURL == "" {
autodiscoverStep++
}
}
if autodiscoverStep == 2 {
autodiscoverURL = createAutodiscover(fmt.Sprintf("autodiscover.%s", domain), false)
if autodiscoverURL == "" {
return nil, "", fmt.Errorf("Invalid domain or no autodiscover DNS record found")
}
}
}
utils.Trace.Printf("Autodiscover step %d - URL: %s\n", autodiscoverStep, autodiscoverURL)
req, err := http.NewRequest("POST", autodiscoverURL, strings.NewReader(r))
req.Header.Add("Content-Type", "text/xml")
req.Header.Add("User-Agent", "ruler")
if mapi == true {
req.Header.Add("X-MapiHttpCapability", "1") //we want MAPI info
req.Header.Add("X-AnchorMailbox", SessionConfig.Email) //we want MAPI info
}
//if we have been redirected to outlook, change the auth header to basic auth
if SessionConfig.Basic == false {
req.SetBasicAuth(SessionConfig.Email, SessionConfig.Pass)
SessionConfig.BasicAuth = req.Header.Get("WWW-Authenticate")
} else {
req.SetBasicAuth(SessionConfig.User, SessionConfig.Pass)
}
//request the autodiscover url
resp, err := client.Do(req)
if err != nil {
//check if this error was because of ntml auth when basic auth was expected.
if m, _ := regexp.Match("illegal base64", []byte(err.Error())); m == true {
client = http.Client{Transport: InsecureRedirectsO365{User: SessionConfig.Email, Pass: SessionConfig.Pass, Insecure: SessionConfig.Insecure}}
resp, err = client.Do(req)
if err != nil {
return nil, "", err
}
} else {
if autodiscoverStep < 2 {
autodiscoverStep++
return autodiscover(domain, mapi)
}
//we've done all three steps of autodiscover and all three failed
return nil, "", err
}
}
defer resp.Body.Close()
body, err := ioutil.ReadAll(resp.Body)
if err != nil {
return nil, "", err
}
//check if we got a 200 response
if resp.StatusCode == 200 {
err := autodiscoverResp.Unmarshal(body)
if err != nil {
if SessionConfig.Verbose == true {
utils.Error.Printf("%s\n", err)
}
if autodiscoverStep < 2 {
autodiscoverStep++
return autodiscover(domain, mapi)
}
return nil, "", fmt.Errorf("Error in autodiscover response, %s", err)
}
SessionConfig.NTLMAuth = req.Header.Get("Authorization")
if SessionConfig.Verbose == true {
//fmt.Println(string(body))
}
//check if we got a RedirectAddr ,
//if yes, get the new autodiscover url
if autodiscoverResp.Response.Account.Action == "redirectAddr" {
rediraddr := autodiscoverResp.Response.Account.RedirectAddr
redirAddrs := strings.Split(rediraddr, "@") //regexp.MustCompile(".*@").Split(rediraddr, 2)
secondaryEmail = fmt.Sprintf("%s@%s", redirAddrs[0], domain)
red, err := redirectAutodiscover(redirAddrs[1])
if err != nil {
return nil, "", err
}
return autodiscover(red, mapi)
}
return &autodiscoverResp, string(body), nil
}
if resp.StatusCode == 401 || resp.StatusCode == 403 || resp.StatusCode == 404 {
//for office365 we might need to use a different email address, try this
if resp.StatusCode == 401 && secondaryEmail != "" {
utils.Trace.Printf("Authentication failed with primary email, trying secondary email [%s]\n", secondaryEmail)
SessionConfig.Email = secondaryEmail
return autodiscover(domain, mapi)
}
if SessionConfig.Verbose == true {
utils.Error.Printf("Failed, StatusCode [%d]\n", resp.StatusCode)
}
if m, _ := regexp.Match("http[s]?://", []byte(domain)); m == true {
return nil, "", fmt.Errorf("Failed to authenticate: StatusCode [%d]\n", resp.StatusCode)
}
if autodiscoverStep < 2 {
autodiscoverStep++
return autodiscover(domain, mapi)
}
return nil, "", fmt.Errorf("Permission Denied or URL not found: StatusCode [%d]\n", resp.StatusCode)
}
if SessionConfig.Verbose == true {
utils.Error.Printf("Failed, StatusCode [%d]\n", resp.StatusCode)
}
if autodiscoverStep < 2 {
autodiscoverStep++
return autodiscover(domain, mapi)
}
return nil, "", fmt.Errorf("Got an unexpected result: StatusCode [%d] %s\n", resp.StatusCode, body)
}
func redirectAutodiscover(redirdom string) (string, error) {
utils.Trace.Printf("Redirected with new address [%s]\n", redirdom)
//create the autodiscover url
autodiscoverURL := fmt.Sprintf("http://autodiscover.%s/autodiscover/autodiscover.xml", redirdom)
req, _ := http.NewRequest("GET", autodiscoverURL, nil)
var DefaultTransport http.RoundTripper = &http.Transport{
TLSClientConfig: &tls.Config{InsecureSkipVerify: SessionConfig.Insecure},
}
resp, err := DefaultTransport.RoundTrip(req)
if err != nil {
return "", err
}
defer resp.Body.Close()
utils.Trace.Printf("Authenticating through: %s\n", string(resp.Header.Get("Location")))
//return the new autodiscover server location
return resp.Header.Get("Location"), nil
}
//InsecureRedirectsO365 allows forwarding the Authorization header even when we shouldn't
type InsecureRedirectsO365 struct {
Transport http.RoundTripper
User string
Pass string
Insecure bool
}
//RoundTrip custom redirector that allows us to forward the auth header, even when the domain changes.
//This is needed as some office365 domains will redirect from autodiscover.domain.com to autodiscover.outlook.com
//and Go does not forward Sensitive headers such as Authorization (https://golang.org/src/net/http/client.go#41)
func (l InsecureRedirectsO365) RoundTrip(req *http.Request) (resp *http.Response, err error) {
t := l.Transport
if t == nil {
t = http.DefaultTransport
}
resp, err = t.RoundTrip(req)
if err != nil {
return
}
switch resp.StatusCode {
case http.StatusMovedPermanently, http.StatusFound, http.StatusSeeOther, http.StatusTemporaryRedirect:
utils.Trace.Printf("Request for %s redirected. Following to %s\n", req.URL, resp.Header.Get("Location"))
URL, _ := url.Parse(resp.Header.Get("Location"))
r, _ := parseTemplate(autodiscoverXML)
//if the domains are different, we need to force the auth cookie to be passed along.. this is for redirects to office365
client := http.Client{Transport: &http.Transport{
TLSClientConfig: &tls.Config{InsecureSkipVerify: l.Insecure},
}}
req, err = http.NewRequest("POST", URL.String(), strings.NewReader(r))
req.Header.Add("Content-Type", "text/xml")
req.Header.Add("User-Agent", "ruler")
req.Header.Add("X-MapiHttpCapability", "1") //we want MAPI info
req.Header.Add("X-AnchorMailbox", l.User) //we want MAPI info
req.URL, _ = url.Parse(resp.Header.Get("Location"))
req.SetBasicAuth(l.User, l.Pass)
resp, err = client.Do(req)
}
return
}