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