2 Unix SMB/Netbios implementation.
4 handle NLTMSSP, client server side parsing
6 Copyright (C) Andrew Tridgell 2001
7 Copyright (C) Andrew Bartlett <abartlet@samba.org> 2001-2005
8 Copyright (C) Stefan Metzmacher 2005
10 This program is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 2 of the License, or
13 (at your option) any later version.
15 This program is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with this program; if not, write to the Free Software
22 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
26 #include "auth/auth.h"
27 #include "auth/ntlmssp/ntlmssp.h"
28 #include "auth/ntlmssp/msrpc_parse.h"
31 * Callbacks for NTLMSSP - for both client and server operating modes
35 static const struct ntlmssp_callbacks {
36 enum ntlmssp_role role;
37 enum ntlmssp_message_type ntlmssp_command;
38 NTSTATUS (*fn)(struct gensec_security *gensec_security,
39 TALLOC_CTX *out_mem_ctx,
40 DATA_BLOB in, DATA_BLOB *out);
41 } ntlmssp_callbacks[] = {
42 {NTLMSSP_CLIENT, NTLMSSP_INITIAL, ntlmssp_client_initial},
43 {NTLMSSP_SERVER, NTLMSSP_NEGOTIATE, ntlmssp_server_negotiate},
44 {NTLMSSP_CLIENT, NTLMSSP_CHALLENGE, ntlmssp_client_challenge},
45 {NTLMSSP_SERVER, NTLMSSP_AUTH, ntlmssp_server_auth},
50 * Print out the NTLMSSP flags for debugging
51 * @param neg_flags The flags from the packet
54 void debug_ntlmssp_flags(uint32_t neg_flags)
56 DEBUG(3,("Got NTLMSSP neg_flags=0x%08x\n", neg_flags));
58 if (neg_flags & NTLMSSP_NEGOTIATE_UNICODE)
59 DEBUGADD(4, (" NTLMSSP_NEGOTIATE_UNICODE\n"));
60 if (neg_flags & NTLMSSP_NEGOTIATE_OEM)
61 DEBUGADD(4, (" NTLMSSP_NEGOTIATE_OEM\n"));
62 if (neg_flags & NTLMSSP_REQUEST_TARGET)
63 DEBUGADD(4, (" NTLMSSP_REQUEST_TARGET\n"));
64 if (neg_flags & NTLMSSP_NEGOTIATE_SIGN)
65 DEBUGADD(4, (" NTLMSSP_NEGOTIATE_SIGN\n"));
66 if (neg_flags & NTLMSSP_NEGOTIATE_SEAL)
67 DEBUGADD(4, (" NTLMSSP_NEGOTIATE_SEAL\n"));
68 if (neg_flags & NTLMSSP_NEGOTIATE_DATAGRAM_STYLE)
69 DEBUGADD(4, (" NTLMSSP_NEGOTIATE_DATAGRAM_STYLE\n"));
70 if (neg_flags & NTLMSSP_NEGOTIATE_LM_KEY)
71 DEBUGADD(4, (" NTLMSSP_NEGOTIATE_LM_KEY\n"));
72 if (neg_flags & NTLMSSP_NEGOTIATE_NETWARE)
73 DEBUGADD(4, (" NTLMSSP_NEGOTIATE_NETWARE\n"));
74 if (neg_flags & NTLMSSP_NEGOTIATE_NTLM)
75 DEBUGADD(4, (" NTLMSSP_NEGOTIATE_NTLM\n"));
76 if (neg_flags & NTLMSSP_NEGOTIATE_DOMAIN_SUPPLIED)
77 DEBUGADD(4, (" NTLMSSP_NEGOTIATE_DOMAIN_SUPPLIED\n"));
78 if (neg_flags & NTLMSSP_NEGOTIATE_WORKSTATION_SUPPLIED)
79 DEBUGADD(4, (" NTLMSSP_NEGOTIATE_WORKSTATION_SUPPLIED\n"));
80 if (neg_flags & NTLMSSP_NEGOTIATE_THIS_IS_LOCAL_CALL)
81 DEBUGADD(4, (" NTLMSSP_NEGOTIATE_THIS_IS_LOCAL_CALL\n"));
82 if (neg_flags & NTLMSSP_NEGOTIATE_ALWAYS_SIGN)
83 DEBUGADD(4, (" NTLMSSP_NEGOTIATE_ALWAYS_SIGN\n"));
84 if (neg_flags & NTLMSSP_CHAL_ACCEPT_RESPONSE)
85 DEBUGADD(4, (" NTLMSSP_CHAL_ACCEPT_RESPONSE\n"));
86 if (neg_flags & NTLMSSP_CHAL_NON_NT_SESSION_KEY)
87 DEBUGADD(4, (" NTLMSSP_CHAL_NON_NT_SESSION_KEY\n"));
88 if (neg_flags & NTLMSSP_NEGOTIATE_NTLM2)
89 DEBUGADD(4, (" NTLMSSP_NEGOTIATE_NTLM2\n"));
90 if (neg_flags & NTLMSSP_CHAL_TARGET_INFO)
91 DEBUGADD(4, (" NTLMSSP_CHAL_TARGET_INFO\n"));
92 if (neg_flags & NTLMSSP_NEGOTIATE_128)
93 DEBUGADD(4, (" NTLMSSP_NEGOTIATE_128\n"));
94 if (neg_flags & NTLMSSP_NEGOTIATE_KEY_EXCH)
95 DEBUGADD(4, (" NTLMSSP_NEGOTIATE_KEY_EXCH\n"));
96 if (neg_flags & NTLMSSP_NEGOTIATE_56)
97 DEBUGADD(4, (" NTLMSSP_NEGOTIATE_56\n"));
100 static NTSTATUS gensec_ntlmssp_magic(struct gensec_security *gensec_security,
101 const DATA_BLOB *first_packet)
103 if (first_packet->length > 8 && memcmp("NTLMSSP\0", first_packet->data, 8) == 0) {
106 return NT_STATUS_INVALID_PARAMETER;
111 * Next state function for the wrapped NTLMSSP state machine
113 * @param gensec_security GENSEC state, initialised to NTLMSSP
114 * @param out_mem_ctx The TALLOC_CTX for *out to be allocated on
115 * @param in The request, as a DATA_BLOB
116 * @param out The reply, as an talloc()ed DATA_BLOB, on *out_mem_ctx
117 * @return Error, MORE_PROCESSING_REQUIRED if a reply is sent,
118 * or NT_STATUS_OK if the user is authenticated.
121 static NTSTATUS gensec_ntlmssp_update(struct gensec_security *gensec_security,
122 TALLOC_CTX *out_mem_ctx,
123 const DATA_BLOB input, DATA_BLOB *out)
125 struct gensec_ntlmssp_state *gensec_ntlmssp_state = gensec_security->private_data;
128 uint32_t ntlmssp_command;
131 *out = data_blob(NULL, 0);
133 if (gensec_ntlmssp_state->expected_state == NTLMSSP_DONE) {
134 /* We are strict here because other modules, which we
135 * don't fully control (such as GSSAPI) are also
136 * strict, but are tested less often */
138 DEBUG(1, ("Called NTLMSSP after state machine was 'done'\n"));
139 return NT_STATUS_INVALID_PARAMETER;
143 /* if the caller doesn't want to manage/own the memory,
144 we can put it on our context */
145 out_mem_ctx = gensec_ntlmssp_state;
149 switch (gensec_ntlmssp_state->role) {
151 ntlmssp_command = NTLMSSP_INITIAL;
154 if (gensec_security->want_features & GENSEC_FEATURE_DATAGRAM_MODE) {
155 /* 'datagram' mode - no neg packet */
156 ntlmssp_command = NTLMSSP_NEGOTIATE;
158 /* This is normal in SPNEGO mech negotiation fallback */
159 DEBUG(2, ("Failed to parse NTLMSSP packet: zero length\n"));
160 return NT_STATUS_INVALID_PARAMETER;
165 if (!msrpc_parse(gensec_ntlmssp_state,
169 DEBUG(1, ("Failed to parse NTLMSSP packet, could not extract NTLMSSP command\n"));
170 dump_data(2, input.data, input.length);
171 return NT_STATUS_INVALID_PARAMETER;
175 if (ntlmssp_command != gensec_ntlmssp_state->expected_state) {
176 DEBUG(2, ("got NTLMSSP command %u, expected %u\n", ntlmssp_command, gensec_ntlmssp_state->expected_state));
177 return NT_STATUS_INVALID_PARAMETER;
180 for (i=0; i < ARRAY_SIZE(ntlmssp_callbacks); i++) {
181 if (ntlmssp_callbacks[i].role == gensec_ntlmssp_state->role
182 && ntlmssp_callbacks[i].ntlmssp_command == ntlmssp_command) {
183 status = ntlmssp_callbacks[i].fn(gensec_security, out_mem_ctx, input, out);
188 if (i == ARRAY_SIZE(ntlmssp_callbacks)) {
190 DEBUG(1, ("failed to find NTLMSSP callback for NTLMSSP mode %u, command %u\n",
191 gensec_ntlmssp_state->role, ntlmssp_command));
193 return NT_STATUS_INVALID_PARAMETER;
196 if (!NT_STATUS_IS_OK(status)) {
197 /* error or more processing required */
205 * Return the NTLMSSP master session key
207 * @param gensec_ntlmssp_state NTLMSSP State
210 NTSTATUS gensec_ntlmssp_session_key(struct gensec_security *gensec_security,
211 DATA_BLOB *session_key)
213 struct gensec_ntlmssp_state *gensec_ntlmssp_state = gensec_security->private_data;
215 if (!gensec_ntlmssp_state->session_key.data) {
216 return NT_STATUS_NO_USER_SESSION_KEY;
218 *session_key = gensec_ntlmssp_state->session_key;
223 void ntlmssp_handle_neg_flags(struct gensec_ntlmssp_state *gensec_ntlmssp_state,
224 uint32_t neg_flags, BOOL allow_lm)
226 if (neg_flags & NTLMSSP_NEGOTIATE_UNICODE) {
227 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_UNICODE;
228 gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_OEM;
229 gensec_ntlmssp_state->unicode = True;
231 gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_UNICODE;
232 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_OEM;
233 gensec_ntlmssp_state->unicode = False;
236 if ((neg_flags & NTLMSSP_NEGOTIATE_LM_KEY) && allow_lm && !gensec_ntlmssp_state->use_ntlmv2) {
237 /* other end forcing us to use LM */
238 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_LM_KEY;
239 gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_NTLM2;
241 gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_LM_KEY;
244 if (neg_flags & NTLMSSP_NEGOTIATE_ALWAYS_SIGN) {
245 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_ALWAYS_SIGN;
248 if (!(neg_flags & NTLMSSP_NEGOTIATE_SIGN)) {
249 gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_SIGN;
252 if (!(neg_flags & NTLMSSP_NEGOTIATE_SEAL)) {
253 gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_SEAL;
256 if (!(neg_flags & NTLMSSP_NEGOTIATE_NTLM2)) {
257 gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_NTLM2;
260 if (!(neg_flags & NTLMSSP_NEGOTIATE_128)) {
261 gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_128;
262 if (neg_flags & NTLMSSP_NEGOTIATE_56) {
263 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_56;
267 if (!(neg_flags & NTLMSSP_NEGOTIATE_56)) {
268 gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_56;
271 if (!(neg_flags & NTLMSSP_NEGOTIATE_KEY_EXCH)) {
272 gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_KEY_EXCH;
275 if ((neg_flags & NTLMSSP_REQUEST_TARGET)) {
276 gensec_ntlmssp_state->neg_flags |= NTLMSSP_REQUEST_TARGET;
282 Weaken NTLMSSP keys to cope with down-level clients and servers.
284 We probably should have some parameters to control this, but as
285 it only occours for LM_KEY connections, and this is controlled
286 by the client lanman auth/lanman auth parameters, it isn't too bad.
289 DATA_BLOB ntlmssp_weakend_key(struct gensec_ntlmssp_state *gensec_ntlmssp_state,
292 DATA_BLOB weakened_key = data_blob_talloc(mem_ctx,
293 gensec_ntlmssp_state->session_key.data,
294 gensec_ntlmssp_state->session_key.length);
295 /* Nothing to weaken. We certainly don't want to 'extend' the length... */
296 if (weakened_key.length < 16) {
297 /* perhaps there was no key? */
301 /* Key weakening not performed on the master key for NTLM2
302 and does not occour for NTLM1. Therefore we only need
303 to do this for the LM_KEY.
305 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_LM_KEY) {
306 /* LM key doesn't support 128 bit crypto, so this is
307 * the best we can do. If you negotiate 128 bit, but
308 * not 56, you end up with 40 bit... */
309 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_56) {
310 weakened_key.data[7] = 0xa0;
311 weakened_key.length = 8;
312 } else { /* forty bits */
313 weakened_key.data[5] = 0xe5;
314 weakened_key.data[6] = 0x38;
315 weakened_key.data[7] = 0xb0;
316 weakened_key.length = 8;
322 static BOOL gensec_ntlmssp_have_feature(struct gensec_security *gensec_security,
325 struct gensec_ntlmssp_state *gensec_ntlmssp_state = gensec_security->private_data;
326 if (feature & GENSEC_FEATURE_SIGN) {
327 if (!gensec_ntlmssp_state->session_key.length) {
330 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_SIGN) {
334 if (feature & GENSEC_FEATURE_SEAL) {
335 if (!gensec_ntlmssp_state->session_key.length) {
338 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_SEAL) {
342 if (feature & GENSEC_FEATURE_SESSION_KEY) {
343 if (gensec_ntlmssp_state->session_key.length) {
347 if (feature & GENSEC_FEATURE_DCE_STYLE) {
350 if (feature & GENSEC_FEATURE_ASYNC_REPLIES) {
351 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
358 NTSTATUS gensec_ntlmssp_start(struct gensec_security *gensec_security)
360 struct gensec_ntlmssp_state *gensec_ntlmssp_state;
362 gensec_ntlmssp_state = talloc_zero(gensec_security, struct gensec_ntlmssp_state);
363 if (!gensec_ntlmssp_state) {
364 return NT_STATUS_NO_MEMORY;
367 gensec_ntlmssp_state->gensec_security = gensec_security;
368 gensec_ntlmssp_state->auth_context = NULL;
369 gensec_ntlmssp_state->server_info = NULL;
371 gensec_security->private_data = gensec_ntlmssp_state;
375 static const char *gensec_ntlmssp_oids[] = {
380 static const struct gensec_security_ops gensec_ntlmssp_security_ops = {
383 .auth_type = DCERPC_AUTH_TYPE_NTLMSSP,
384 .oid = gensec_ntlmssp_oids,
385 .client_start = gensec_ntlmssp_client_start,
386 .server_start = gensec_ntlmssp_server_start,
387 .magic = gensec_ntlmssp_magic,
388 .update = gensec_ntlmssp_update,
389 .sig_size = gensec_ntlmssp_sig_size,
390 .sign_packet = gensec_ntlmssp_sign_packet,
391 .check_packet = gensec_ntlmssp_check_packet,
392 .seal_packet = gensec_ntlmssp_seal_packet,
393 .unseal_packet = gensec_ntlmssp_unseal_packet,
394 .wrap = gensec_ntlmssp_wrap,
395 .unwrap = gensec_ntlmssp_unwrap,
396 .session_key = gensec_ntlmssp_session_key,
397 .session_info = gensec_ntlmssp_session_info,
398 .have_feature = gensec_ntlmssp_have_feature,
403 NTSTATUS gensec_ntlmssp_init(void)
406 ret = gensec_register(&gensec_ntlmssp_security_ops);
407 if (!NT_STATUS_IS_OK(ret)) {
408 DEBUG(0,("Failed to register '%s' gensec backend!\n",
409 gensec_ntlmssp_security_ops.name));