1 ;;; ntlm.el --- NTLM (NT LanManager) authentication support
3 ;; Copyright (C) 2001, 2007-2015 Free Software Foundation, Inc.
5 ;; Author: Taro Kawagishi <tarok@transpulse.org>
6 ;; Keywords: NTLM, SASL
8 ;; Created: February 2001
10 ;; This file is part of GNU Emacs.
12 ;; GNU Emacs is free software: you can redistribute it and/or modify
13 ;; it under the terms of the GNU General Public License as published by
14 ;; the Free Software Foundation, either version 3 of the License, or
15 ;; (at your option) any later version.
17 ;; GNU Emacs is distributed in the hope that it will be useful,
18 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
19 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 ;; GNU General Public License for more details.
22 ;; You should have received a copy of the GNU General Public License
23 ;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.
27 ;; This library is a direct translation of the Samba release 2.2.0
28 ;; implementation of Windows NT and LanManager compatible password
31 ;; Interface functions:
33 ;; ntlm-build-auth-request
34 ;; This will return a binary string, which should be used in the
35 ;; base64 encoded form and it is the caller's responsibility to encode
36 ;; the returned string with base64.
38 ;; ntlm-build-auth-response
39 ;; It is the caller's responsibility to pass a base64 decoded string
40 ;; (which will be a binary string) as the first argument and to
41 ;; encode the returned string with base64. The second argument user
42 ;; should be given in user@domain format.
44 ;; ntlm-get-password-hashes
47 ;; NTLM authentication procedure example:
49 ;; 1. Open a network connection to the Exchange server at the IMAP port (143)
50 ;; 2. Receive an opening message such as:
51 ;; "* OK Microsoft Exchange IMAP4rev1 server version 5.5.2653.7 (XXXX) ready"
52 ;; 3. Ask for IMAP server capability by sending "NNN capability"
53 ;; 4. Receive a capability message such as:
54 ;; "* CAPABILITY IMAP4 IMAP4rev1 IDLE LITERAL+ LOGIN-REFERRALS MAILBOX-REFERRALS NAMESPACE AUTH=NTLM"
55 ;; 5. Ask for NTLM authentication by sending a string
56 ;; "NNN authenticate ntlm"
57 ;; 6. Receive continuation acknowledgment "+"
58 ;; 7. Send NTLM authentication request generated by 'ntlm-build-auth-request
59 ;; 8. Receive NTLM challenge string following acknowledgment "+"
60 ;; 9. Generate response to challenge by 'ntlm-build-auth-response
61 ;; (here two hash function values of the user password are encrypted)
62 ;; 10. Receive authentication completion message such as
63 ;; "NNN OK AUTHENTICATE NTLM completed."
70 ;;; NTLM authentication interface functions
72 (defun ntlm-build-auth-request (user &optional domain
)
73 "Return the NTLM authentication request string for USER and DOMAIN.
74 USER is a string representing a user name to be authenticated and
75 DOMAIN is a NT domain. USER can include a NT domain part as in
76 user@domain where the string after @ is used as the domain if DOMAIN
79 (let ((request-ident (concat "NTLMSSP" (make-string 1 0)))
80 (request-msgType (concat (make-string 1 1) (make-string 3 0)))
82 (request-flags (concat (make-string 1 7) (make-string 1 178)
83 (make-string 1 8) (make-string 1 0)))
86 (when (string-match "@" user
)
88 (setq domain
(substring user
(1+ (match-beginning 0)))))
89 (setq user
(substring user
0 (match-beginning 0))))
90 ;; set fields offsets within the request struct
91 (setq lu
(length user
))
92 (setq ld
(length domain
))
93 (setq off-u
32) ;offset to the string 'user
94 (setq off-d
(+ 32 lu
)) ;offset to the string 'domain
95 ;; pack the request struct in a string
96 (concat request-ident
;8 bytes
97 request-msgType
;4 bytes
98 request-flags
;4 bytes
99 (md4-pack-int16 lu
) ;user field, count field
100 (md4-pack-int16 lu
) ;user field, max count field
101 (md4-pack-int32 (cons 0 off-u
)) ;user field, offset field
102 (md4-pack-int16 ld
) ;domain field, count field
103 (md4-pack-int16 ld
) ;domain field, max count field
104 (md4-pack-int32 (cons 0 off-d
)) ;domain field, offset field
110 (defmacro ntlm-string-as-unibyte
(string)
111 (if (fboundp 'string-as-unibyte
)
112 `(string-as-unibyte ,string
)
115 (defun ntlm-build-auth-response (challenge user password-hashes
)
116 "Return the response string to a challenge string CHALLENGE given by
117 the NTLM based server for the user USER and the password hash list
118 PASSWORD-HASHES. NTLM uses two hash values which are represented
119 by PASSWORD-HASHES. PASSWORD-HASHES should be a return value of
120 (list (ntlm-smb-passwd-hash password) (ntlm-md4hash password))"
121 (let* ((rchallenge (ntlm-string-as-unibyte challenge
))
122 ;; get fields within challenge struct
123 ;;(ident (substring rchallenge 0 8)) ;ident, 8 bytes
124 ;;(msgType (substring rchallenge 8 12)) ;msgType, 4 bytes
125 (uDomain (substring rchallenge
12 20)) ;uDomain, 8 bytes
126 (flags (substring rchallenge
20 24)) ;flags, 4 bytes
127 (challengeData (substring rchallenge
24 32)) ;challengeData, 8 bytes
128 uDomain-len uDomain-offs
129 ;; response struct and its fields
130 lmRespData
;lmRespData, 24 bytes
131 ntRespData
;ntRespData, 24 bytes
132 domain
;ascii domain string
133 lu ld off-lm off-nt off-d off-u off-w off-s
)
134 ;; extract domain string from challenge string
135 (setq uDomain-len
(md4-unpack-int16 (substring uDomain
0 2)))
136 (setq uDomain-offs
(md4-unpack-int32 (substring uDomain
4 8)))
138 (ntlm-unicode2ascii (substring challenge
140 (+ (cdr uDomain-offs
) uDomain-len
))
142 ;; overwrite domain in case user is given in <user>@<domain> format
143 (when (string-match "@" user
)
144 (setq domain
(substring user
(1+ (match-beginning 0))))
145 (setq user
(substring user
0 (match-beginning 0))))
147 ;; check if "negotiate NTLM2 key" flag is set in type 2 message
148 (if (not (zerop (logand (aref flags
2) 8)))
151 ;; generate NTLM2 session response data
152 (setq randomString
(string-make-unibyte
154 (make-string 1 (random 256))
155 (make-string 1 (random 256))
156 (make-string 1 (random 256))
157 (make-string 1 (random 256))
158 (make-string 1 (random 256))
159 (make-string 1 (random 256))
160 (make-string 1 (random 256))
161 (make-string 1 (random 256)))))
162 (setq sessionHash
(secure-hash 'md5
163 (concat challengeData randomString
)
165 (setq sessionHash
(substring sessionHash
0 8))
167 (setq lmRespData
(concat randomString
(make-string 16 0)))
168 (setq ntRespData
(ntlm-smb-owf-encrypt
169 (cadr password-hashes
) sessionHash
)))
171 ;; generate response data
173 (ntlm-smb-owf-encrypt (car password-hashes
) challengeData
))
175 (ntlm-smb-owf-encrypt (cadr password-hashes
) challengeData
))))
177 ;; get offsets to fields to pack the response struct in a string
178 (setq lu
(length user
))
179 (setq ld
(length domain
))
180 (setq off-lm
64) ;offset to string 'lmResponse
181 (setq off-nt
(+ 64 24)) ;offset to string 'ntResponse
182 (setq off-d
(+ 64 48)) ;offset to string 'uDomain
183 (setq off-u
(+ 64 48 (* 2 ld
))) ;offset to string 'uUser
184 (setq off-w
(+ 64 48 (* 2 (+ ld lu
)))) ;offset to string 'uWks
185 (setq off-s
(+ 64 48 (* 2 (+ ld lu lu
)))) ;offset to string 'sessionKey
186 ;; pack the response struct in a string
187 (concat "NTLMSSP\0" ;response ident field, 8 bytes
188 (md4-pack-int32 '(0 .
3)) ;response msgType field, 4 bytes
190 ;; lmResponse field, 8 bytes
191 ;;AddBytes(response,lmResponse,lmRespData,24);
192 (md4-pack-int16 24) ;len field
193 (md4-pack-int16 24) ;maxlen field
194 (md4-pack-int32 (cons 0 off-lm
)) ;field offset
196 ;; ntResponse field, 8 bytes
197 ;;AddBytes(response,ntResponse,ntRespData,24);
198 (md4-pack-int16 24) ;len field
199 (md4-pack-int16 24) ;maxlen field
200 (md4-pack-int32 (cons 0 off-nt
)) ;field offset
202 ;; uDomain field, 8 bytes
203 ;;AddUnicodeString(response,uDomain,domain);
204 ;;AddBytes(response, uDomain, udomain, 2*ld);
205 (md4-pack-int16 (* 2 ld
)) ;len field
206 (md4-pack-int16 (* 2 ld
)) ;maxlen field
207 (md4-pack-int32 (cons 0 off-d
)) ;field offset
209 ;; uUser field, 8 bytes
210 ;;AddUnicodeString(response,uUser,u);
211 ;;AddBytes(response, uUser, uuser, 2*lu);
212 (md4-pack-int16 (* 2 lu
)) ;len field
213 (md4-pack-int16 (* 2 lu
)) ;maxlen field
214 (md4-pack-int32 (cons 0 off-u
)) ;field offset
216 ;; uWks field, 8 bytes
217 ;;AddUnicodeString(response,uWks,u);
218 (md4-pack-int16 (* 2 lu
)) ;len field
219 (md4-pack-int16 (* 2 lu
)) ;maxlen field
220 (md4-pack-int32 (cons 0 off-w
)) ;field offset
222 ;; sessionKey field, 8 bytes
223 ;;AddString(response,sessionKey,NULL);
224 (md4-pack-int16 0) ;len field
225 (md4-pack-int16 0) ;maxlen field
226 (md4-pack-int32 (cons 0 (- off-s off-lm
))) ;field offset
228 ;; flags field, 4 bytes
232 lmRespData
;lmResponse, 24 bytes
233 ntRespData
;ntResponse, 24 bytes
234 (ntlm-ascii2unicode domain
;Unicode domain string, 2*ld bytes
236 (ntlm-ascii2unicode user
;Unicode user string, 2*lu bytes
238 (ntlm-ascii2unicode user
;Unicode user string, 2*lu bytes
242 (defun ntlm-get-password-hashes (password)
243 "Return a pair of SMB hash and NT MD4 hash of the given password PASSWORD."
244 (list (ntlm-smb-passwd-hash password
)
245 (ntlm-md4hash password
)))
247 (defun ntlm-ascii2unicode (str len
)
248 "Convert an ASCII string into a NT Unicode string, which is
249 little-endian utf16."
250 (let ((utf (make-string (* 2 len
) 0)) (i 0) val
)
251 (while (and (< i len
)
252 (not (zerop (setq val
(aref str i
)))))
253 (aset utf
(* 2 i
) val
)
254 (aset utf
(1+ (* 2 i
)) 0)
258 (defun ntlm-unicode2ascii (str len
)
259 "Extract 7 bits ASCII part of a little endian utf16 string STR of length LEN."
260 (let ((buf (make-string len
0)) (i 0) (j 0))
262 (aset buf i
(logand (aref str j
) 127)) ;(string-to-number "7f" 16)
267 (defun ntlm-smb-passwd-hash (passwd)
268 "Return the SMB password hash string of 16 bytes long for the given password
269 string PASSWD. PASSWD is truncated to 14 bytes if longer."
270 (let ((len (min (length passwd
) 14)))
272 (concat (substring (upcase passwd
) 0 len
) ;fill top 14 bytes with passwd
273 (make-string (- 15 len
) 0)))))
275 (defun ntlm-smb-owf-encrypt (passwd c8
)
276 "Return the response string of 24 bytes long for the given password
277 string PASSWD based on the DES encryption. PASSWD is of at most 14
278 bytes long and the challenge string C8 of 8 bytes long."
279 (let ((len (min (length passwd
) 16)) p22
)
280 (setq p22
(concat (substring passwd
0 len
) ;fill top 16 bytes with passwd
281 (make-string (- 22 len
) 0)))
282 (ntlm-smb-des-e-p24 p22 c8
)))
284 (defun ntlm-smb-des-e-p24 (p22 c8
)
285 "Return a 24 bytes hashed string for a 21 bytes string P22 and a 8 bytes
287 (concat (ntlm-smb-hash c8 p22 t
) ;hash first 8 bytes of p22
288 (ntlm-smb-hash c8
(substring p22
7) t
)
289 (ntlm-smb-hash c8
(substring p22
14) t
)))
291 (defconst ntlm-smb-sp8
[75 71 83 33 64 35 36 37])
293 (defun ntlm-smb-des-e-p16 (p15)
294 "Return a 16 bytes hashed string for a 15 bytes string P15."
295 (concat (ntlm-smb-hash ntlm-smb-sp8 p15 t
) ;hash of first 8 bytes of p15
296 (ntlm-smb-hash ntlm-smb-sp8
;hash of last 8 bytes of p15
297 (substring p15
7) t
)))
299 (defun ntlm-smb-hash (in key forw
)
300 "Return the hash string of length 8 for a string IN of length 8 and
301 a string KEY of length 8. FORW is t or nil."
302 (let ((out (make-string 8 0))
303 outb
;string of length 64
304 (inb (make-string 64 0))
305 (keyb (make-string 64 0))
306 (key2 (ntlm-smb-str-to-key key
))
309 (unless (zerop (logand (aref in
(/ i
8)) (lsh 1 (- 7 (% i
8)))))
311 (unless (zerop (logand (aref key2
(/ i
8)) (lsh 1 (- 7 (% i
8)))))
314 (setq outb
(ntlm-smb-dohash inb keyb forw
))
317 (unless (zerop (aref outb i
))
318 (setq aa
(aref out
(/ i
8)))
320 (logior aa
(lsh 1 (- 7 (% i
8))))))
324 (defun ntlm-smb-str-to-key (str)
325 "Return a string of length 8 for the given string STR of length 7."
326 (let ((key (make-string 8 0))
328 (aset key
0 (lsh (aref str
0) -
1))
330 (lsh (logand (aref str
0) 1) 6)
331 (lsh (aref str
1) -
2)))
333 (lsh (logand (aref str
1) 3) 5)
334 (lsh (aref str
2) -
3)))
336 (lsh (logand (aref str
2) 7) 4)
337 (lsh (aref str
3) -
4)))
339 (lsh (logand (aref str
3) 15) 3)
340 (lsh (aref str
4) -
5)))
342 (lsh (logand (aref str
4) 31) 2)
343 (lsh (aref str
5) -
6)))
345 (lsh (logand (aref str
5) 63) 1)
346 (lsh (aref str
6) -
7)))
347 (aset key
7 (logand (aref str
6) 127))
349 (aset key i
(lsh (aref key i
) 1))
353 (defconst ntlm-smb-perm1
[57 49 41 33 25 17 9
362 (defconst ntlm-smb-perm2
[14 17 11 24 1 5
371 (defconst ntlm-smb-perm3
[58 50 42 34 26 18 10 2
372 60 52 44 36 28 20 12 4
373 62 54 46 38 30 22 14 6
374 64 56 48 40 32 24 16 8
375 57 49 41 33 25 17 9 1
376 59 51 43 35 27 19 11 3
377 61 53 45 37 29 21 13 5
378 63 55 47 39 31 23 15 7])
380 (defconst ntlm-smb-perm4
[32 1 2 3 4 5
389 (defconst ntlm-smb-perm5
[16 7 20 21
398 (defconst ntlm-smb-perm6
[40 8 48 16 56 24 64 32
399 39 7 47 15 55 23 63 31
400 38 6 46 14 54 22 62 30
401 37 5 45 13 53 21 61 29
402 36 4 44 12 52 20 60 28
403 35 3 43 11 51 19 59 27
404 34 2 42 10 50 18 58 26
405 33 1 41 9 49 17 57 25])
407 (defconst ntlm-smb-sc
[1 1 2 2 2 2 2 2 1 2 2 2 2 2 2 1])
409 (defconst ntlm-smb-sbox
[[[14 4 13 1 2 15 11 8 3 10 6 12 5 9 0 7]
410 [ 0 15 7 4 14 2 13 1 10 6 12 11 9 5 3 8]
411 [ 4 1 14 8 13 6 2 11 15 12 9 7 3 10 5 0]
412 [15 12 8 2 4 9 1 7 5 11 3 14 10 0 6 13]]
413 [[15 1 8 14 6 11 3 4 9 7 2 13 12 0 5 10]
414 [ 3 13 4 7 15 2 8 14 12 0 1 10 6 9 11 5]
415 [ 0 14 7 11 10 4 13 1 5 8 12 6 9 3 2 15]
416 [13 8 10 1 3 15 4 2 11 6 7 12 0 5 14 9]]
417 [[10 0 9 14 6 3 15 5 1 13 12 7 11 4 2 8]
418 [13 7 0 9 3 4 6 10 2 8 5 14 12 11 15 1]
419 [13 6 4 9 8 15 3 0 11 1 2 12 5 10 14 7]
420 [ 1 10 13 0 6 9 8 7 4 15 14 3 11 5 2 12]]
421 [[ 7 13 14 3 0 6 9 10 1 2 8 5 11 12 4 15]
422 [13 8 11 5 6 15 0 3 4 7 2 12 1 10 14 9]
423 [10 6 9 0 12 11 7 13 15 1 3 14 5 2 8 4]
424 [ 3 15 0 6 10 1 13 8 9 4 5 11 12 7 2 14]]
425 [[ 2 12 4 1 7 10 11 6 8 5 3 15 13 0 14 9]
426 [14 11 2 12 4 7 13 1 5 0 15 10 3 9 8 6]
427 [ 4 2 1 11 10 13 7 8 15 9 12 5 6 3 0 14]
428 [11 8 12 7 1 14 2 13 6 15 0 9 10 4 5 3]]
429 [[12 1 10 15 9 2 6 8 0 13 3 4 14 7 5 11]
430 [10 15 4 2 7 12 9 5 6 1 13 14 0 11 3 8]
431 [ 9 14 15 5 2 8 12 3 7 0 4 10 1 13 11 6]
432 [ 4 3 2 12 9 5 15 10 11 14 1 7 6 0 8 13]]
433 [[ 4 11 2 14 15 0 8 13 3 12 9 7 5 10 6 1]
434 [13 0 11 7 4 9 1 10 14 3 5 12 2 15 8 6]
435 [ 1 4 11 13 12 3 7 14 10 15 6 8 0 5 9 2]
436 [ 6 11 13 8 1 4 10 7 9 5 0 15 14 2 3 12]]
437 [[13 2 8 4 6 15 11 1 10 9 3 14 5 0 12 7]
438 [ 1 15 13 8 10 3 7 4 12 5 6 11 0 14 9 2]
439 [ 7 11 4 1 9 12 14 2 0 6 10 13 15 3 5 8]
440 [ 2 1 14 7 4 10 8 13 15 12 9 0 3 5 6 11]]])
442 (defsubst ntlm-string-permute
(in perm n
)
443 "Return a string of length N for a string IN and a permutation vector
444 PERM of size N. The length of IN should be height of PERM."
445 (let ((i 0) (out (make-string n
0)))
447 (aset out i
(aref in
(- (aref perm i
) 1)))
451 (defsubst ntlm-string-lshift
(str count len
)
452 "Return a string by circularly shifting a string STR by COUNT to the left.
453 length of STR is LEN."
454 (let ((c (% count len
)))
455 (concat (substring str c len
) (substring str
0 c
))))
457 (defsubst ntlm-string-xor
(in1 in2 n
)
458 "Return exclusive-or of sequences in1 and in2"
459 (let ((w (make-string n
0)) (i 0))
461 (aset w i
(logxor (aref in1 i
) (aref in2 i
)))
465 (defun ntlm-smb-dohash (in key forw
)
466 "Return the hash value for a string IN and a string KEY.
467 Length of IN and KEY are 64. FORW non-nil means forward, nil means
469 (let (pk1 ;string of length 56
470 c
;string of length 28
471 d
;string of length 28
472 cd
;string of length 56
473 (ki (make-vector 16 0)) ;vector of string of length 48
474 pd1
;string of length 64
475 l
;string of length 32
476 r
;string of length 32
477 rl
;string of length 64
479 (setq pk1
(ntlm-string-permute key ntlm-smb-perm1
56))
480 (setq c
(substring pk1
0 28))
481 (setq d
(substring pk1
28 56))
485 (setq c
(ntlm-string-lshift c
(aref ntlm-smb-sc i
) 28))
486 (setq d
(ntlm-string-lshift d
(aref ntlm-smb-sc i
) 28))
487 (setq cd
(concat (substring c
0 28) (substring d
0 28)))
488 (aset ki i
(ntlm-string-permute cd ntlm-smb-perm2
48))
491 (setq pd1
(ntlm-string-permute in ntlm-smb-perm3
64))
493 (setq l
(substring pd1
0 32))
494 (setq r
(substring pd1
32 64))
497 (let (er ;string of length 48
498 erk
;string of length 48
499 (b (make-vector 8 0)) ;vector of strings of length 6
500 cb
;string of length 32
501 pcb
;string of length 32
502 r2
;string of length 32
505 (setq er
(ntlm-string-permute r ntlm-smb-perm4
48))
506 (setq erk
(ntlm-string-xor er
507 (aref ki
(if forw i
(- 15 i
)))
512 (aset b j
(substring erk jj
(+ jj
6)))
517 (setq m
(logior (lsh (aref bj
0) 1) (aref bj
5)))
518 (setq n
(logior (lsh (aref bj
1) 3)
523 (setq sbox-jmn
(aref (aref (aref ntlm-smb-sbox j
) m
) n
))
526 (if (zerop (logand sbox-jmn
(lsh 1 (- 3 k
))))
534 (setq cb
(concat cb
(substring (aref b j
) 0 4)))
537 (setq pcb
(ntlm-string-permute cb ntlm-smb-perm5
32))
538 (setq r2
(ntlm-string-xor l pcb
32))
542 (setq rl
(concat r l
))
543 (ntlm-string-permute rl ntlm-smb-perm6
64)))
545 (defun ntlm-md4hash (passwd)
546 "Return the 16 bytes MD4 hash of a string PASSWD after converting it
547 into a Unicode string. PASSWD is truncated to 128 bytes if longer."
549 ;; Password cannot be longer than 128 characters
550 (setq len
(length passwd
))
553 ;; Password must be converted to NT Unicode
554 (setq wpwd
(ntlm-ascii2unicode passwd len
))
555 ;; Calculate length in bytes
561 ;;; ntlm.el ends here