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