source4/smb_server/negprot.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    negprot reply code
   4    Copyright (C) Andrew Tridgell 1992-1998
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 2 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, write to the Free Software
  18    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19 */
  20
  21 #include "includes.h"
  22 #include "auth/auth.h"
  23 #include "smb_server/smb_server.h"
  24
  25
  26 /* initialise the auth_context for this server and return the cryptkey */
  27 static NTSTATUS get_challenge(struct smbsrv_connection *smb_conn, uint8_t buff[8])
  28 {
  29         NTSTATUS nt_status;
  30         const uint8_t *challenge;
  31
  32         /* muliple negprots are not premitted */
  33         if (smb_conn->negotiate.auth_context) {
  34                 DEBUG(3,("get challenge: is this a secondary negprot?  auth_context is non-NULL!\n"));
  35                 return NT_STATUS_FOOBAR;
  36         }
  37
  38         DEBUG(10, ("get challenge: creating negprot_global_auth_context\n"));
  39
  40         nt_status = auth_context_create(smb_conn, lp_auth_methods(), &smb_conn->negotiate.auth_context);
  41         if (!NT_STATUS_IS_OK(nt_status)) {
  42                 DEBUG(0, ("auth_context_create() returned %s", nt_errstr(nt_status)));
  43                 return nt_status;
  44         }
  45
  46         nt_status = auth_context_create(smb_conn, lp_auth_methods(), &smb_conn->negotiate.auth_context);
  47         if (!NT_STATUS_IS_OK(nt_status)) {
  48                 DEBUG(0, ("auth_context_create() returned %s", nt_errstr(nt_status)));
  49                 return nt_status;
  50         }
  51
  52         nt_status = auth_get_challenge(smb_conn->negotiate.auth_context, &challenge);
  53         if (!NT_STATUS_IS_OK(nt_status)) {
  54                 DEBUG(0, ("auth_get_challenge() returned %s", nt_errstr(nt_status)));
  55                 return nt_status;
  56         }
  57
  58         memcpy(buff, challenge, 8);
  59
  60         return NT_STATUS_OK;
  61 }
  62
  63 /****************************************************************************
  64  Reply for the core protocol.
  65 ****************************************************************************/
  66 static void reply_corep(struct smbsrv_request *req, uint16_t choice)
  67 {
  68         req_setup_reply(req, 1, 0);
  69
  70         SSVAL(req->out.vwv, VWV(0), choice);
  71
  72         req->smb_conn->negotiate.protocol = PROTOCOL_CORE;
  73
  74         if (req->smb_conn->signing.mandatory_signing) {
  75                 smbsrv_terminate_connection(req->smb_conn,
  76                                             "CORE does not support SMB signing, and it is mandatory\n");
  77                 return;
  78         }
  79
  80         req_send_reply(req);
  81 }
  82
  83 /****************************************************************************
  84  Reply for the coreplus protocol.
  85 this is quite incomplete - we only fill in a small part of the reply, but as nobody uses
  86 this any more it probably doesn't matter
  87 ****************************************************************************/
  88 static void reply_coreplus(struct smbsrv_request *req, uint16_t choice)
  89 {
  90         uint16_t raw = (lp_readraw()?1:0) | (lp_writeraw()?2:0);
  91
  92         req_setup_reply(req, 13, 0);
  93
  94         /* Reply, SMBlockread, SMBwritelock supported. */
  95         SCVAL(req->out.hdr,HDR_FLG,
  96               CVAL(req->out.hdr, HDR_FLG) | FLAG_SUPPORT_LOCKREAD);
  97
  98         SSVAL(req->out.vwv, VWV(0), choice);
  99         SSVAL(req->out.vwv, VWV(1), 0x1); /* user level security, don't encrypt */
 100
 101         /* tell redirector we support
 102            readbraw and writebraw (possibly) */
 103         SSVAL(req->out.vwv, VWV(5), raw);
 104
 105         req->smb_conn->negotiate.protocol = PROTOCOL_COREPLUS;
 106
 107         if (req->smb_conn->signing.mandatory_signing) {
 108                 smbsrv_terminate_connection(req->smb_conn,
 109                                             "COREPLUS does not support SMB signing, and it is mandatory\n");
 110                 return;
 111         }
 112
 113         req_send_reply(req);
 114 }
 115
 116 /****************************************************************************
 117  Reply for the lanman 1.0 protocol.
 118 ****************************************************************************/
 119 static void reply_lanman1(struct smbsrv_request *req, uint16_t choice)
 120 {
 121         int raw = (lp_readraw()?1:0) | (lp_writeraw()?2:0);
 122         int secword=0;
 123         time_t t = req->request_time.tv_sec;
 124
 125         req->smb_conn->negotiate.encrypted_passwords = lp_encrypted_passwords();
 126
 127         if (lp_security() != SEC_SHARE)
 128                 secword |= NEGOTIATE_SECURITY_USER_LEVEL;
 129
 130         if (req->smb_conn->negotiate.encrypted_passwords)
 131                 secword |= NEGOTIATE_SECURITY_CHALLENGE_RESPONSE;
 132
 133         req->smb_conn->negotiate.protocol = PROTOCOL_LANMAN1;
 134
 135         req_setup_reply(req, 13, req->smb_conn->negotiate.encrypted_passwords ? 8 : 0);
 136
 137         /* SMBlockread, SMBwritelock supported. */
 138         SCVAL(req->out.hdr,HDR_FLG,
 139               CVAL(req->out.hdr, HDR_FLG) | FLAG_SUPPORT_LOCKREAD);
 140
 141         SSVAL(req->out.vwv, VWV(0), choice);
 142         SSVAL(req->out.vwv, VWV(1), secword);
 143         SSVAL(req->out.vwv, VWV(2), req->smb_conn->negotiate.max_recv);
 144         SSVAL(req->out.vwv, VWV(3), lp_maxmux());
 145         SSVAL(req->out.vwv, VWV(4), 1);
 146         SSVAL(req->out.vwv, VWV(5), raw);
 147         SIVAL(req->out.vwv, VWV(6), req->smb_conn->connection->connection.id);
 148         srv_push_dos_date(req->smb_conn, req->out.vwv, VWV(8), t);
 149         SSVAL(req->out.vwv, VWV(10), req->smb_conn->negotiate.zone_offset/60);
 150         SIVAL(req->out.vwv, VWV(11), 0); /* reserved */
 151
 152         /* Create a token value and add it to the outgoing packet. */
 153         if (req->smb_conn->negotiate.encrypted_passwords) {
 154                 NTSTATUS nt_status;
 155
 156                 SSVAL(req->out.vwv, VWV(11), 8);
 157
 158                 nt_status = get_challenge(req->smb_conn, req->out.data);
 159                 if (!NT_STATUS_IS_OK(nt_status)) {
 160                         smbsrv_terminate_connection(req->smb_conn, "LANMAN1 get_challenge failed\n");
 161                         return;
 162                 }
 163         }
 164
 165         if (req->smb_conn->signing.mandatory_signing) {
 166                 smbsrv_terminate_connection(req->smb_conn,
 167                                             "LANMAN1 does not support SMB signing, and it is mandatory\n");
 168                 return;
 169         }
 170
 171         req_send_reply(req);
 172 }
 173
 174 /****************************************************************************
 175  Reply for the lanman 2.0 protocol.
 176 ****************************************************************************/
 177 static void reply_lanman2(struct smbsrv_request *req, uint16_t choice)
 178 {
 179         int raw = (lp_readraw()?1:0) | (lp_writeraw()?2:0);
 180         int secword=0;
 181         time_t t = req->request_time.tv_sec;
 182
 183         req->smb_conn->negotiate.encrypted_passwords = lp_encrypted_passwords();
 184
 185         if (lp_security() != SEC_SHARE)
 186                 secword |= NEGOTIATE_SECURITY_USER_LEVEL;
 187
 188         if (req->smb_conn->negotiate.encrypted_passwords)
 189                 secword |= NEGOTIATE_SECURITY_CHALLENGE_RESPONSE;
 190
 191         req->smb_conn->negotiate.protocol = PROTOCOL_LANMAN2;
 192
 193         req_setup_reply(req, 13, 0);
 194
 195         SSVAL(req->out.vwv, VWV(0), choice);
 196         SSVAL(req->out.vwv, VWV(1), secword);
 197         SSVAL(req->out.vwv, VWV(2), req->smb_conn->negotiate.max_recv);
 198         SSVAL(req->out.vwv, VWV(3), lp_maxmux());
 199         SSVAL(req->out.vwv, VWV(4), 1);
 200         SSVAL(req->out.vwv, VWV(5), raw);
 201         SIVAL(req->out.vwv, VWV(6), req->smb_conn->connection->connection.id);
 202         srv_push_dos_date(req->smb_conn, req->out.vwv, VWV(8), t);
 203         SSVAL(req->out.vwv, VWV(10), req->smb_conn->negotiate.zone_offset/60);
 204         SIVAL(req->out.vwv, VWV(11), 0);
 205
 206         /* Create a token value and add it to the outgoing packet. */
 207         if (req->smb_conn->negotiate.encrypted_passwords) {
 208                 SSVAL(req->out.vwv, VWV(11), 8);
 209                 req_grow_data(req, 8);
 210                 get_challenge(req->smb_conn, req->out.data);
 211         }
 212
 213         req_push_str(req, NULL, lp_workgroup(), -1, STR_TERMINATE);
 214
 215         if (req->smb_conn->signing.mandatory_signing) {
 216                 smbsrv_terminate_connection(req->smb_conn,
 217                                             "LANMAN2 does not support SMB signing, and it is mandatory\n");
 218                 return;
 219         }
 220
 221         req_send_reply(req);
 222 }
 223
 224 /****************************************************************************
 225  Reply for the nt protocol.
 226 ****************************************************************************/
 227 static void reply_nt1(struct smbsrv_request *req, uint16_t choice)
 228 {
 229         /* dual names + lock_and_read + nt SMBs + remote API calls */
 230         int capabilities;
 231         int secword=0;
 232         time_t t = req->request_time.tv_sec;
 233         NTTIME nttime;
 234         BOOL negotiate_spnego = False;
 235
 236         unix_to_nt_time(&nttime, t);
 237
 238         capabilities =
 239                 CAP_NT_FIND | CAP_LOCK_AND_READ |
 240                 CAP_LEVEL_II_OPLOCKS | CAP_NT_SMBS | CAP_RPC_REMOTE_APIS;
 241
 242         req->smb_conn->negotiate.encrypted_passwords = lp_encrypted_passwords();
 243
 244         /* do spnego in user level security if the client
 245            supports it and we can do encrypted passwords */
 246
 247         if (req->smb_conn->negotiate.encrypted_passwords &&
 248             (lp_security() != SEC_SHARE) &&
 249             lp_use_spnego() &&
 250             (req->flags2 & FLAGS2_EXTENDED_SECURITY)) {
 251                 negotiate_spnego = True;
 252                 capabilities |= CAP_EXTENDED_SECURITY;
 253         }
 254
 255         if (lp_unix_extensions()) {
 256                 capabilities |= CAP_UNIX;
 257         }
 258
 259         if (lp_large_readwrite()) {
 260                 capabilities |= CAP_LARGE_READX | CAP_LARGE_WRITEX | CAP_W2K_SMBS;
 261         }
 262
 263         capabilities |= CAP_LARGE_FILES;
 264
 265         if (lp_readraw() && lp_writeraw()) {
 266                 capabilities |= CAP_RAW_MODE;
 267         }
 268
 269         /* allow for disabling unicode */
 270         if (lp_unicode()) {
 271                 capabilities |= CAP_UNICODE;
 272         }
 273
 274         if (lp_nt_status_support()) {
 275                 capabilities |= CAP_STATUS32;
 276         }
 277
 278         if (lp_host_msdfs()) {
 279                 capabilities |= CAP_DFS;
 280         }
 281
 282         if (lp_security() != SEC_SHARE) {
 283                 secword |= NEGOTIATE_SECURITY_USER_LEVEL;
 284         }
 285
 286         if (req->smb_conn->negotiate.encrypted_passwords) {
 287                 secword |= NEGOTIATE_SECURITY_CHALLENGE_RESPONSE;
 288         }
 289
 290         if (req->smb_conn->signing.allow_smb_signing) {
 291                 secword |= NEGOTIATE_SECURITY_SIGNATURES_ENABLED;
 292         }
 293
 294         if (req->smb_conn->signing.mandatory_signing) {
 295                 secword |= NEGOTIATE_SECURITY_SIGNATURES_REQUIRED;
 296         }
 297
 298         req->smb_conn->negotiate.protocol = PROTOCOL_NT1;
 299
 300         req_setup_reply(req, 17, 0);
 301
 302         SSVAL(req->out.vwv, VWV(0), choice);
 303         SCVAL(req->out.vwv, VWV(1), secword);
 304
 305         /* notice the strange +1 on vwv here? That's because
 306            this is the one and only SMB packet that is malformed in
 307            the specification - all the command words after the secword
 308            are offset by 1 byte */
 309         SSVAL(req->out.vwv+1, VWV(1), lp_maxmux());
 310         SSVAL(req->out.vwv+1, VWV(2), 1); /* num vcs */
 311         SIVAL(req->out.vwv+1, VWV(3), req->smb_conn->negotiate.max_recv);
 312         SIVAL(req->out.vwv+1, VWV(5), 0x10000); /* raw size. full 64k */
 313         SIVAL(req->out.vwv+1, VWV(7), req->smb_conn->connection->connection.id); /* session key */
 314         SIVAL(req->out.vwv+1, VWV(9), capabilities);
 315         push_nttime(req->out.vwv+1, VWV(11), nttime);
 316         SSVALS(req->out.vwv+1,VWV(15), req->smb_conn->negotiate.zone_offset/60);
 317
 318         if (!negotiate_spnego) {
 319                 /* Create a token value and add it to the outgoing packet. */
 320                 if (req->smb_conn->negotiate.encrypted_passwords) {
 321                         req_grow_data(req, 8);
 322                         /* note that we do not send a challenge at all if
 323                            we are using plaintext */
 324                         get_challenge(req->smb_conn, req->out.ptr);
 325                         req->out.ptr += 8;
 326                         SCVAL(req->out.vwv+1, VWV(16), 8);
 327                 }
 328                 req_push_str(req, NULL, lp_workgroup(), -1, STR_UNICODE|STR_TERMINATE|STR_NOALIGN);
 329                 req_push_str(req, NULL, lp_netbios_name(), -1, STR_UNICODE|STR_TERMINATE|STR_NOALIGN);
 330                 DEBUG(3,("not using SPNEGO\n"));
 331         } else {
 332                 struct gensec_security *gensec_security;
 333                 DATA_BLOB null_data_blob = data_blob(NULL, 0);
 334                 DATA_BLOB blob;
 335                 NTSTATUS nt_status = gensec_server_start(req->smb_conn, &gensec_security);
 336
 337                 if (req->smb_conn->negotiate.auth_context) {
 338                         smbsrv_terminate_connection(req->smb_conn, "reply_nt1: is this a secondary negprot?  auth_context is non-NULL!\n");
 339                         return;
 340                 }
 341
 342                 req->smb_conn->negotiate.auth_context = NULL;
 343
 344                 if (!NT_STATUS_IS_OK(nt_status)) {
 345                         DEBUG(0, ("Failed to start GENSEC: %s\n", nt_errstr(nt_status)));
 346                         smbsrv_terminate_connection(req->smb_conn, "Failed to start GENSEC\n");
 347                         return;
 348                 }
 349
 350                 nt_status = gensec_start_mech_by_oid(gensec_security, GENSEC_OID_SPNEGO);
 351
 352                 if (!NT_STATUS_IS_OK(nt_status)) {
 353                         DEBUG(0, ("Failed to start SPNEGO: %s\n", nt_errstr(nt_status)));
 354                         smbsrv_terminate_connection(req->smb_conn, "Failed to start SPNEGO\n");
 355                         return;
 356                 }
 357
 358                 nt_status = gensec_update(gensec_security, req, null_data_blob, &blob);
 359
 360                 if (!NT_STATUS_IS_OK(nt_status) && !NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 361                         DEBUG(0, ("Failed to get SPNEGO to give us the first token: %s\n", nt_errstr(nt_status)));
 362                         smbsrv_terminate_connection(req->smb_conn, "Failed to start SPNEGO - no first token\n");
 363                         return;
 364                 }
 365
 366                 req->smb_conn->negotiate.spnego_negotiated = True;
 367
 368                 req_grow_data(req, blob.length + 16);
 369                 /* a NOT very random guid */
 370                 memset(req->out.ptr, '\0', 16);
 371                 req->out.ptr += 16;
 372
 373                 memcpy(req->out.ptr, blob.data, blob.length);
 374                 SCVAL(req->out.vwv+1, VWV(16), blob.length + 16);
 375                 req->out.ptr += blob.length;
 376                 DEBUG(3,("using SPNEGO\n"));
 377         }
 378
 379         req_send_reply_nosign(req);
 380 }
 381
 382
 383 /* List of supported protocols, most desired first */
 384 static const struct {
 385         const char *proto_name;
 386         const char *short_name;
 387         void (*proto_reply_fn)(struct smbsrv_request *req, uint16_t choice);
 388         int protocol_level;
 389 } supported_protocols[] = {
 390         {"NT LANMAN 1.0",           "NT1",      reply_nt1,      PROTOCOL_NT1},
 391         {"NT LM 0.12",              "NT1",      reply_nt1,      PROTOCOL_NT1},
 392         {"LANMAN2.1",               "LANMAN2",  reply_lanman2,  PROTOCOL_LANMAN2},
 393         {"LM1.2X002",               "LANMAN2",  reply_lanman2,  PROTOCOL_LANMAN2},
 394         {"Samba",                   "LANMAN2",  reply_lanman2,  PROTOCOL_LANMAN2},
 395         {"DOS LM1.2X002",           "LANMAN2",  reply_lanman2,  PROTOCOL_LANMAN2},
 396         {"LANMAN1.0",               "LANMAN1",  reply_lanman1,  PROTOCOL_LANMAN1},
 397         {"MICROSOFT NETWORKS 3.0",  "LANMAN1",  reply_lanman1,  PROTOCOL_LANMAN1},
 398         {"MICROSOFT NETWORKS 1.03", "COREPLUS", reply_coreplus, PROTOCOL_COREPLUS},
 399         {"PC NETWORK PROGRAM 1.0",  "CORE",     reply_corep,    PROTOCOL_CORE},
 400         {NULL,NULL,NULL,0},
 401 };
 402
 403 /****************************************************************************
 404  Reply to a negprot.
 405 ****************************************************************************/
 406
 407 void reply_negprot(struct smbsrv_request *req)
 408 {
 409         int Index=0;
 410         int choice = -1;
 411         int protocol;
 412         uint8_t *p;
 413
 414         if (req->smb_conn->negotiate.done_negprot) {
 415                 smbsrv_terminate_connection(req->smb_conn, "multiple negprot's are not permitted");
 416                 return;
 417         }
 418         req->smb_conn->negotiate.done_negprot = True;
 419
 420         p = req->in.data + 1;
 421
 422         while (p < req->in.data + req->in.data_size) {
 423                 Index++;
 424                 DEBUG(3,("Requested protocol [%s]\n",(const char *)p));
 425                 p += strlen((const char *)p) + 2;
 426         }
 427
 428         /* Check for protocols, most desirable first */
 429         for (protocol = 0; supported_protocols[protocol].proto_name; protocol++) {
 430                 p = req->in.data+1;
 431                 Index = 0;
 432                 if ((supported_protocols[protocol].protocol_level <= lp_maxprotocol()) &&
 433                                 (supported_protocols[protocol].protocol_level >= lp_minprotocol()))
 434                         while (p < (req->in.data + req->in.data_size)) {
 435                                 if (strequal((const char *)p,supported_protocols[protocol].proto_name))
 436                                         choice = Index;
 437                                 Index++;
 438                                 p += strlen((const char *)p) + 2;
 439                         }
 440                 if(choice != -1)
 441                         break;
 442         }
 443
 444         if(choice != -1) {
 445                 sub_set_remote_proto(supported_protocols[protocol].short_name);
 446                 reload_services(req->smb_conn, True);
 447                 supported_protocols[protocol].proto_reply_fn(req, choice);
 448                 DEBUG(3,("Selected protocol %s\n",supported_protocols[protocol].proto_name));
 449         } else {
 450                 DEBUG(0,("No protocol supported !\n"));
 451         }
 452
 453         DEBUG(5,("negprot index=%d\n", choice));
 454 }