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 "asn_1.h"
  24 #include "smb_server/smb_server.h"
  25
  26
  27 /* initialise the auth_context for this server and return the cryptkey */
  28 static void get_challenge(struct smbsrv_connection *smb_conn, char buff[8])
  29 {
  30         NTSTATUS nt_status;
  31         const uint8_t *cryptkey;
  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                 smb_panic("secondary negprot");
  37         }
  38
  39         DEBUG(10, ("get challenge: creating negprot_global_auth_context\n"));
  40
  41         nt_status = make_auth_context_subsystem(smb_conn, &smb_conn->negotiate.auth_context);
  42
  43         if (!NT_STATUS_IS_OK(nt_status)) {
  44                 DEBUG(0, ("make_auth_context_subsystem returned %s", nt_errstr(nt_status)));
  45                 smb_panic("cannot make_negprot_global_auth_context!\n");
  46         }
  47
  48         DEBUG(10, ("get challenge: getting challenge\n"));
  49         cryptkey = smb_conn->negotiate.auth_context->get_ntlm_challenge(smb_conn->negotiate.auth_context);
  50         memcpy(buff, cryptkey, 8);
  51 }
  52
  53 /****************************************************************************
  54  Reply for the core protocol.
  55 ****************************************************************************/
  56 static void reply_corep(struct smbsrv_request *req, uint16_t choice)
  57 {
  58         req_setup_reply(req, 1, 0);
  59
  60         SSVAL(req->out.vwv, VWV(0), choice);
  61
  62         req->smb_conn->negotiate.protocol = PROTOCOL_CORE;
  63
  64         if (req->smb_conn->signing.mandatory_signing) {
  65                 smbsrv_terminate_connection(req->smb_conn,
  66                                             "CORE does not support SMB signing, and it is mandetory\n");
  67         }
  68
  69         req_send_reply(req);
  70 }
  71
  72 /****************************************************************************
  73  Reply for the coreplus protocol.
  74 this is quite incomplete - we only fill in a small part of the reply, but as nobody uses
  75 this any more it probably doesn't matter
  76 ****************************************************************************/
  77 static void reply_coreplus(struct smbsrv_request *req, uint16_t choice)
  78 {
  79         uint16_t raw = (lp_readraw()?1:0) | (lp_writeraw()?2:0);
  80
  81         req_setup_reply(req, 13, 0);
  82
  83         /* Reply, SMBlockread, SMBwritelock supported. */
  84         SCVAL(req->out.hdr,HDR_FLG,
  85               CVAL(req->out.hdr, HDR_FLG) | FLAG_SUPPORT_LOCKREAD);
  86
  87         SSVAL(req->out.vwv, VWV(0), choice);
  88         SSVAL(req->out.vwv, VWV(1), 0x1); /* user level security, don't encrypt */
  89
  90         /* tell redirector we support
  91            readbraw and writebraw (possibly) */
  92         SSVAL(req->out.vwv, VWV(5), raw);
  93
  94         req->smb_conn->negotiate.protocol = PROTOCOL_COREPLUS;
  95
  96         if (req->smb_conn->signing.mandatory_signing) {
  97                 smbsrv_terminate_connection(req->smb_conn,
  98                                             "COREPLUS does not support SMB signing, and it is mandetory\n");
  99         }
 100
 101         req_send_reply(req);
 102 }
 103
 104 /****************************************************************************
 105  Reply for the lanman 1.0 protocol.
 106 ****************************************************************************/
 107 static void reply_lanman1(struct smbsrv_request *req, uint16_t choice)
 108 {
 109         int raw = (lp_readraw()?1:0) | (lp_writeraw()?2:0);
 110         int secword=0;
 111         time_t t = req->request_time.tv_sec;
 112
 113         req->smb_conn->negotiate.encrypted_passwords = lp_encrypted_passwords();
 114
 115         if (lp_security() != SEC_SHARE)
 116                 secword |= NEGOTIATE_SECURITY_USER_LEVEL;
 117
 118         if (req->smb_conn->negotiate.encrypted_passwords)
 119                 secword |= NEGOTIATE_SECURITY_CHALLENGE_RESPONSE;
 120
 121         req->smb_conn->negotiate.protocol = PROTOCOL_LANMAN1;
 122
 123         req_setup_reply(req, 13, req->smb_conn->negotiate.encrypted_passwords ? 8 : 0);
 124
 125         /* SMBlockread, SMBwritelock supported. */
 126         SCVAL(req->out.hdr,HDR_FLG,
 127               CVAL(req->out.hdr, HDR_FLG) | FLAG_SUPPORT_LOCKREAD);
 128
 129         SSVAL(req->out.vwv, VWV(0), choice);
 130         SSVAL(req->out.vwv, VWV(1), secword);
 131         SSVAL(req->out.vwv, VWV(2), req->smb_conn->negotiate.max_recv);
 132         SSVAL(req->out.vwv, VWV(3), lp_maxmux());
 133         SSVAL(req->out.vwv, VWV(4), 1);
 134         SSVAL(req->out.vwv, VWV(5), raw);
 135         SIVAL(req->out.vwv, VWV(6), req->smb_conn->pid);
 136         srv_push_dos_date(req->smb_conn, req->out.vwv, VWV(8), t);
 137         SSVAL(req->out.vwv, VWV(10), req->smb_conn->negotiate.zone_offset/60);
 138         SIVAL(req->out.vwv, VWV(11), 0); /* reserved */
 139
 140         /* Create a token value and add it to the outgoing packet. */
 141         if (req->smb_conn->negotiate.encrypted_passwords) {
 142                 SSVAL(req->out.vwv, VWV(11), 8);
 143                 get_challenge(req->smb_conn, req->out.data);
 144         }
 145
 146         if (req->smb_conn->signing.mandatory_signing) {
 147                 smbsrv_terminate_connection(req->smb_conn,
 148                                             "LANMAN1 does not support SMB signing, and it is mandetory\n");
 149         }
 150
 151         req_send_reply(req);
 152 }
 153
 154 /****************************************************************************
 155  Reply for the lanman 2.0 protocol.
 156 ****************************************************************************/
 157 static void reply_lanman2(struct smbsrv_request *req, uint16_t choice)
 158 {
 159         int raw = (lp_readraw()?1:0) | (lp_writeraw()?2:0);
 160         int secword=0;
 161         time_t t = req->request_time.tv_sec;
 162
 163         req->smb_conn->negotiate.encrypted_passwords = lp_encrypted_passwords();
 164
 165         if (lp_security() != SEC_SHARE)
 166                 secword |= NEGOTIATE_SECURITY_USER_LEVEL;
 167
 168         if (req->smb_conn->negotiate.encrypted_passwords)
 169                 secword |= NEGOTIATE_SECURITY_CHALLENGE_RESPONSE;
 170
 171         req->smb_conn->negotiate.protocol = PROTOCOL_LANMAN2;
 172
 173         req_setup_reply(req, 13, 0);
 174
 175         SSVAL(req->out.vwv, VWV(0), choice);
 176         SSVAL(req->out.vwv, VWV(1), secword);
 177         SSVAL(req->out.vwv, VWV(2), req->smb_conn->negotiate.max_recv);
 178         SSVAL(req->out.vwv, VWV(3), lp_maxmux());
 179         SSVAL(req->out.vwv, VWV(4), 1);
 180         SSVAL(req->out.vwv, VWV(5), raw);
 181         SIVAL(req->out.vwv, VWV(6), req->smb_conn->pid);
 182         srv_push_dos_date(req->smb_conn, req->out.vwv, VWV(8), t);
 183         SSVAL(req->out.vwv, VWV(10), req->smb_conn->negotiate.zone_offset/60);
 184
 185         /* Create a token value and add it to the outgoing packet. */
 186         if (req->smb_conn->negotiate.encrypted_passwords) {
 187                 SSVAL(req->out.vwv, VWV(11), 8);
 188                 req_grow_data(req, 8);
 189                 get_challenge(req->smb_conn, req->out.data);
 190         }
 191
 192         req_push_str(req, NULL, lp_workgroup(), -1, STR_TERMINATE);
 193
 194         if (req->smb_conn->signing.mandatory_signing) {
 195                 smbsrv_terminate_connection(req->smb_conn,
 196                                             "LANMAN2 does not support SMB signing, and it is mandetory\n");
 197         }
 198
 199         req_send_reply(req);
 200 }
 201
 202 /****************************************************************************
 203  Reply for the nt protocol.
 204 ****************************************************************************/
 205 static void reply_nt1(struct smbsrv_request *req, uint16_t choice)
 206 {
 207         /* dual names + lock_and_read + nt SMBs + remote API calls */
 208         int capabilities;
 209         int secword=0;
 210         time_t t = req->request_time.tv_sec;
 211         NTTIME nttime;
 212         BOOL negotiate_spnego = False;
 213
 214         unix_to_nt_time(&nttime, t);
 215
 216         capabilities =
 217                 CAP_NT_FIND | CAP_LOCK_AND_READ |
 218                 CAP_LEVEL_II_OPLOCKS | CAP_NT_SMBS | CAP_RPC_REMOTE_APIS;
 219
 220         req->smb_conn->negotiate.encrypted_passwords = lp_encrypted_passwords();
 221
 222         /* do spnego in user level security if the client
 223            supports it and we can do encrypted passwords */
 224
 225         if (req->smb_conn->negotiate.encrypted_passwords &&
 226             (lp_security() != SEC_SHARE) &&
 227             lp_use_spnego() &&
 228             (req->flags2 & FLAGS2_EXTENDED_SECURITY)) {
 229                 negotiate_spnego = True;
 230                 capabilities |= CAP_EXTENDED_SECURITY;
 231         }
 232
 233         if (lp_unix_extensions()) {
 234                 capabilities |= CAP_UNIX;
 235         }
 236
 237         if (lp_large_readwrite()) {
 238                 capabilities |= CAP_LARGE_READX | CAP_LARGE_WRITEX | CAP_W2K_SMBS;
 239         }
 240
 241         capabilities |= CAP_LARGE_FILES;
 242
 243         if (lp_readraw() && lp_writeraw()) {
 244                 capabilities |= CAP_RAW_MODE;
 245         }
 246
 247         /* allow for disabling unicode */
 248         if (lp_unicode()) {
 249                 capabilities |= CAP_UNICODE;
 250         }
 251
 252         if (lp_nt_status_support()) {
 253                 capabilities |= CAP_STATUS32;
 254         }
 255
 256         if (lp_host_msdfs()) {
 257                 capabilities |= CAP_DFS;
 258         }
 259
 260         if (lp_security() != SEC_SHARE) {
 261                 secword |= NEGOTIATE_SECURITY_USER_LEVEL;
 262         }
 263
 264         if (req->smb_conn->negotiate.encrypted_passwords) {
 265                 secword |= NEGOTIATE_SECURITY_CHALLENGE_RESPONSE;
 266         }
 267
 268         if (req->smb_conn->signing.allow_smb_signing) {
 269                 secword |= NEGOTIATE_SECURITY_SIGNATURES_ENABLED;
 270         }
 271
 272         if (req->smb_conn->signing.mandatory_signing) {
 273                 secword |= NEGOTIATE_SECURITY_SIGNATURES_REQUIRED;
 274         }
 275
 276         req->smb_conn->negotiate.protocol = PROTOCOL_NT1;
 277
 278         req_setup_reply(req, 17, 0);
 279
 280         SSVAL(req->out.vwv, VWV(0), choice);
 281         SCVAL(req->out.vwv, VWV(1), secword);
 282
 283         /* notice the strange +1 on vwv here? That's because
 284            this is the one and only SMB packet that is malformed in
 285            the specification - all the command words after the secword
 286            are offset by 1 byte */
 287         SSVAL(req->out.vwv+1, VWV(1), lp_maxmux());
 288         SSVAL(req->out.vwv+1, VWV(2), 1); /* num vcs */
 289         SIVAL(req->out.vwv+1, VWV(3), req->smb_conn->negotiate.max_recv);
 290         SIVAL(req->out.vwv+1, VWV(5), 0x10000); /* raw size. full 64k */
 291         SIVAL(req->out.vwv+1, VWV(7), req->smb_conn->pid); /* session key */
 292         SIVAL(req->out.vwv+1, VWV(9), capabilities);
 293         push_nttime(req->out.vwv+1, VWV(11), nttime);
 294         SSVALS(req->out.vwv+1,VWV(15), req->smb_conn->negotiate.zone_offset/60);
 295
 296         if (!negotiate_spnego) {
 297                 /* Create a token value and add it to the outgoing packet. */
 298                 if (req->smb_conn->negotiate.encrypted_passwords) {
 299                         req_grow_data(req, 8);
 300                         /* note that we do not send a challenge at all if
 301                            we are using plaintext */
 302                         get_challenge(req->smb_conn, req->out.ptr);
 303                         req->out.ptr += 8;
 304                         SCVAL(req->out.vwv+1, VWV(16), 8);
 305                 }
 306                 req_push_str(req, NULL, lp_workgroup(), -1, STR_UNICODE|STR_TERMINATE|STR_NOALIGN);
 307                 req_push_str(req, NULL, lp_netbios_name(), -1, STR_UNICODE|STR_TERMINATE|STR_NOALIGN);
 308                 DEBUG(3,("not using SPNEGO\n"));
 309         } else {
 310                 struct gensec_security *gensec_security;
 311                 DATA_BLOB null_data_blob = data_blob(NULL, 0);
 312                 DATA_BLOB blob;
 313                 NTSTATUS nt_status = gensec_server_start(req->smb_conn, &gensec_security);
 314
 315                 if (req->smb_conn->negotiate.auth_context) {
 316                         smbsrv_terminate_connection(req->smb_conn, "reply_nt1: is this a secondary negprot?  auth_context is non-NULL!\n");
 317                         return;
 318                 }
 319
 320                 req->smb_conn->negotiate.auth_context = NULL;
 321
 322                 if (!NT_STATUS_IS_OK(nt_status)) {
 323                         DEBUG(0, ("Failed to start GENSEC: %s\n", nt_errstr(nt_status)));
 324                         smbsrv_terminate_connection(req->smb_conn, "Failed to start GENSEC\n");
 325                         return;
 326                 }
 327
 328                 nt_status = gensec_start_mech_by_oid(gensec_security, OID_SPNEGO);
 329
 330                 if (!NT_STATUS_IS_OK(nt_status)) {
 331                         DEBUG(0, ("Failed to start SPNEGO: %s\n", nt_errstr(nt_status)));
 332                         smbsrv_terminate_connection(req->smb_conn, "Failed to start SPNEGO\n");
 333                         return;
 334                 }
 335
 336                 nt_status = gensec_update(gensec_security, req, null_data_blob, &blob);
 337
 338                 if (!NT_STATUS_IS_OK(nt_status) && !NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 339                         DEBUG(0, ("Failed to get SPNEGO to give us the first token: %s\n", nt_errstr(nt_status)));
 340                         smbsrv_terminate_connection(req->smb_conn, "Failed to start SPNEGO - no first token\n");
 341                         return;
 342                 }
 343
 344                 req->smb_conn->negotiate.spnego_negotiated = True;
 345
 346                 req_grow_data(req, blob.length + 16);
 347                 /* a NOT very random guid */
 348                 memset(req->out.ptr, '\0', 16);
 349                 req->out.ptr += 16;
 350
 351                 memcpy(req->out.ptr, blob.data, blob.length);
 352                 SCVAL(req->out.vwv+1, VWV(16), blob.length + 16);
 353                 req->out.ptr += blob.length;
 354                 DEBUG(3,("using SPNEGO\n"));
 355         }
 356
 357         req_send_reply_nosign(req);
 358 }
 359
 360
 361 /* List of supported protocols, most desired first */
 362 static const struct {
 363         const char *proto_name;
 364         const char *short_name;
 365         void (*proto_reply_fn)(struct smbsrv_request *req, uint16_t choice);
 366         int protocol_level;
 367 } supported_protocols[] = {
 368         {"NT LANMAN 1.0",           "NT1",      reply_nt1,      PROTOCOL_NT1},
 369         {"NT LM 0.12",              "NT1",      reply_nt1,      PROTOCOL_NT1},
 370         {"LM1.2X002",               "LANMAN2",  reply_lanman2,  PROTOCOL_LANMAN2},
 371         {"Samba",                   "LANMAN2",  reply_lanman2,  PROTOCOL_LANMAN2},
 372         {"DOS LM1.2X002",           "LANMAN2",  reply_lanman2,  PROTOCOL_LANMAN2},
 373         {"LANMAN1.0",               "LANMAN1",  reply_lanman1,  PROTOCOL_LANMAN1},
 374         {"MICROSOFT NETWORKS 3.0",  "LANMAN1",  reply_lanman1,  PROTOCOL_LANMAN1},
 375         {"MICROSOFT NETWORKS 1.03", "COREPLUS", reply_coreplus, PROTOCOL_COREPLUS},
 376         {"PC NETWORK PROGRAM 1.0",  "CORE",     reply_corep,    PROTOCOL_CORE},
 377         {NULL,NULL,NULL,0},
 378 };
 379
 380 /****************************************************************************
 381  Reply to a negprot.
 382 ****************************************************************************/
 383
 384 void reply_negprot(struct smbsrv_request *req)
 385 {
 386         int Index=0;
 387         int choice = -1;
 388         int protocol;
 389         char *p;
 390
 391         if (req->smb_conn->negotiate.done_negprot) {
 392                 smbsrv_terminate_connection(req->smb_conn, "multiple negprot's are not permitted");
 393                 return;
 394         }
 395         req->smb_conn->negotiate.done_negprot = True;
 396
 397         p = req->in.data + 1;
 398
 399         while (p < req->in.data + req->in.data_size) {
 400                 Index++;
 401                 DEBUG(3,("Requested protocol [%s]\n",p));
 402                 p += strlen(p) + 2;
 403         }
 404
 405         /* Check for protocols, most desirable first */
 406         for (protocol = 0; supported_protocols[protocol].proto_name; protocol++) {
 407                 p = req->in.data+1;
 408                 Index = 0;
 409                 if ((supported_protocols[protocol].protocol_level <= lp_maxprotocol()) &&
 410                                 (supported_protocols[protocol].protocol_level >= lp_minprotocol()))
 411                         while (p < (req->in.data + req->in.data_size)) {
 412                                 if (strequal(p,supported_protocols[protocol].proto_name))
 413                                         choice = Index;
 414                                 Index++;
 415                                 p += strlen(p) + 2;
 416                         }
 417                 if(choice != -1)
 418                         break;
 419         }
 420
 421         if(choice != -1) {
 422                 sub_set_remote_proto(supported_protocols[protocol].short_name);
 423                 reload_services(req->smb_conn, True);
 424                 supported_protocols[protocol].proto_reply_fn(req, choice);
 425                 DEBUG(3,("Selected protocol %s\n",supported_protocols[protocol].proto_name));
 426         } else {
 427                 DEBUG(0,("No protocol supported !\n"));
 428         }
 429
 430         DEBUG(5,("negprot index=%d\n", choice));
 431 }