source4/smb_server/smb/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 3 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, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "includes.h"
  21 #include "auth/credentials/credentials.h"
  22 #include "auth/gensec/gensec.h"
  23 #include "auth/auth.h"
  24 #include "smb_server/smb_server.h"
  25 #include "libcli/smb2/smb2.h"
  26 #include "smb_server/smb2/smb2_server.h"
  27 #include "smbd/service_stream.h"
  28 #include "lib/stream/packet.h"
  29 #include "param/param.h"
  30
  31
  32 /* initialise the auth_context for this server and return the cryptkey */
  33 static NTSTATUS get_challenge(struct smbsrv_connection *smb_conn, uint8_t buff[8])
  34 {
  35         NTSTATUS nt_status;
  36
  37         /* muliple negprots are not premitted */
  38         if (smb_conn->negotiate.auth_context) {
  39                 DEBUG(3,("get challenge: is this a secondary negprot?  auth_context is non-NULL!\n"));
  40                 return NT_STATUS_FOOBAR;
  41         }
  42
  43         DEBUG(10, ("get challenge: creating negprot_global_auth_context\n"));
  44
  45         nt_status = auth_context_create(smb_conn,
  46                                         smb_conn->connection->event.ctx,
  47                                         smb_conn->connection->msg_ctx,
  48                                         smb_conn->lp_ctx,
  49                                         &smb_conn->negotiate.auth_context);
  50         if (!NT_STATUS_IS_OK(nt_status)) {
  51                 DEBUG(0, ("auth_context_create() returned %s", nt_errstr(nt_status)));
  52                 return nt_status;
  53         }
  54
  55         nt_status = auth_get_challenge(smb_conn->negotiate.auth_context, buff);
  56         if (!NT_STATUS_IS_OK(nt_status)) {
  57                 DEBUG(0, ("auth_get_challenge() returned %s", nt_errstr(nt_status)));
  58                 return nt_status;
  59         }
  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         smbsrv_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         smbsrv_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;
  92         if (lpcfg_async_smb_echo_handler(req->smb_conn->lp_ctx)) {
  93                 raw = 0;
  94         } else {
  95                 raw = (lpcfg_read_raw(req->smb_conn->lp_ctx)?1:0) |
  96                       (lpcfg_write_raw(req->smb_conn->lp_ctx)?2:0);
  97         }
  98
  99         smbsrv_setup_reply(req, 13, 0);
 100
 101         /* Reply, SMBlockread, SMBwritelock supported. */
 102         SCVAL(req->out.hdr,HDR_FLG,
 103               CVAL(req->out.hdr, HDR_FLG) | FLAG_SUPPORT_LOCKREAD);
 104
 105         SSVAL(req->out.vwv, VWV(0), choice);
 106         SSVAL(req->out.vwv, VWV(1), 0x1); /* user level security, don't encrypt */
 107
 108         /* tell redirector we support
 109            readbraw and writebraw (possibly) */
 110         SSVAL(req->out.vwv, VWV(5), raw);
 111
 112         req->smb_conn->negotiate.protocol = PROTOCOL_COREPLUS;
 113
 114         if (req->smb_conn->signing.mandatory_signing) {
 115                 smbsrv_terminate_connection(req->smb_conn,
 116                                             "COREPLUS does not support SMB signing, and it is mandatory\n");
 117                 return;
 118         }
 119
 120         smbsrv_send_reply(req);
 121 }
 122
 123 /****************************************************************************
 124  Reply for the lanman 1.0 protocol.
 125 ****************************************************************************/
 126 static void reply_lanman1(struct smbsrv_request *req, uint16_t choice)
 127 {
 128         uint16_t raw;
 129         if (lpcfg_async_smb_echo_handler(req->smb_conn->lp_ctx)) {
 130                 raw = 0;
 131         } else {
 132                 raw = (lpcfg_read_raw(req->smb_conn->lp_ctx)?1:0) |
 133                       (lpcfg_write_raw(req->smb_conn->lp_ctx)?2:0);
 134         }
 135         int secword=0;
 136         time_t t = req->request_time.tv_sec;
 137
 138         req->smb_conn->negotiate.encrypted_passwords = lpcfg_encrypt_passwords(req->smb_conn->lp_ctx);
 139
 140         if (req->smb_conn->negotiate.encrypted_passwords)
 141                 secword |= NEGOTIATE_SECURITY_CHALLENGE_RESPONSE;
 142
 143         req->smb_conn->negotiate.protocol = PROTOCOL_LANMAN1;
 144
 145         smbsrv_setup_reply(req, 13, req->smb_conn->negotiate.encrypted_passwords ? 8 : 0);
 146
 147         /* SMBlockread, SMBwritelock supported. */
 148         SCVAL(req->out.hdr,HDR_FLG,
 149               CVAL(req->out.hdr, HDR_FLG) | FLAG_SUPPORT_LOCKREAD);
 150
 151         SSVAL(req->out.vwv, VWV(0), choice);
 152         SSVAL(req->out.vwv, VWV(1), secword);
 153         SSVAL(req->out.vwv, VWV(2), req->smb_conn->negotiate.max_recv);
 154         SSVAL(req->out.vwv, VWV(3), lpcfg_max_mux(req->smb_conn->lp_ctx));
 155         SSVAL(req->out.vwv, VWV(4), 1);
 156         SSVAL(req->out.vwv, VWV(5), raw);
 157         SIVAL(req->out.vwv, VWV(6), req->smb_conn->connection->server_id.pid);
 158         srv_push_dos_date(req->smb_conn, req->out.vwv, VWV(8), t);
 159         SSVAL(req->out.vwv, VWV(10), req->smb_conn->negotiate.zone_offset/60);
 160         SIVAL(req->out.vwv, VWV(11), 0); /* reserved */
 161
 162         /* Create a token value and add it to the outgoing packet. */
 163         if (req->smb_conn->negotiate.encrypted_passwords) {
 164                 NTSTATUS nt_status;
 165
 166                 SSVAL(req->out.vwv, VWV(11), 8);
 167
 168                 nt_status = get_challenge(req->smb_conn, req->out.data);
 169                 if (!NT_STATUS_IS_OK(nt_status)) {
 170                         smbsrv_terminate_connection(req->smb_conn, "LANMAN1 get_challenge failed\n");
 171                         return;
 172                 }
 173         }
 174
 175         if (req->smb_conn->signing.mandatory_signing) {
 176                 smbsrv_terminate_connection(req->smb_conn,
 177                                             "LANMAN1 does not support SMB signing, and it is mandatory\n");
 178                 return;
 179         }
 180
 181         smbsrv_send_reply(req);
 182 }
 183
 184 /****************************************************************************
 185  Reply for the lanman 2.0 protocol.
 186 ****************************************************************************/
 187 static void reply_lanman2(struct smbsrv_request *req, uint16_t choice)
 188 {
 189         int secword=0;
 190         time_t t = req->request_time.tv_sec;
 191         uint16_t raw;
 192         if (lpcfg_async_smb_echo_handler(req->smb_conn->lp_ctx)) {
 193                 raw = 0;
 194         } else {
 195                 raw = (lpcfg_read_raw(req->smb_conn->lp_ctx)?1:0) |
 196                       (lpcfg_write_raw(req->smb_conn->lp_ctx)?2:0);
 197         }
 198
 199         req->smb_conn->negotiate.encrypted_passwords = lpcfg_encrypt_passwords(req->smb_conn->lp_ctx);
 200
 201         if (req->smb_conn->negotiate.encrypted_passwords)
 202                 secword |= NEGOTIATE_SECURITY_CHALLENGE_RESPONSE;
 203
 204         req->smb_conn->negotiate.protocol = PROTOCOL_LANMAN2;
 205
 206         smbsrv_setup_reply(req, 13, 0);
 207
 208         SSVAL(req->out.vwv, VWV(0), choice);
 209         SSVAL(req->out.vwv, VWV(1), secword);
 210         SSVAL(req->out.vwv, VWV(2), req->smb_conn->negotiate.max_recv);
 211         SSVAL(req->out.vwv, VWV(3), lpcfg_max_mux(req->smb_conn->lp_ctx));
 212         SSVAL(req->out.vwv, VWV(4), 1);
 213         SSVAL(req->out.vwv, VWV(5), raw);
 214         SIVAL(req->out.vwv, VWV(6), req->smb_conn->connection->server_id.pid);
 215         srv_push_dos_date(req->smb_conn, req->out.vwv, VWV(8), t);
 216         SSVAL(req->out.vwv, VWV(10), req->smb_conn->negotiate.zone_offset/60);
 217         SIVAL(req->out.vwv, VWV(11), 0);
 218
 219         /* Create a token value and add it to the outgoing packet. */
 220         if (req->smb_conn->negotiate.encrypted_passwords) {
 221                 SSVAL(req->out.vwv, VWV(11), 8);
 222                 req_grow_data(req, 8);
 223                 get_challenge(req->smb_conn, req->out.data);
 224         }
 225
 226         req_push_str(req, NULL, lpcfg_workgroup(req->smb_conn->lp_ctx), -1, STR_TERMINATE);
 227
 228         if (req->smb_conn->signing.mandatory_signing) {
 229                 smbsrv_terminate_connection(req->smb_conn,
 230                                             "LANMAN2 does not support SMB signing, and it is mandatory\n");
 231                 return;
 232         }
 233
 234         smbsrv_send_reply(req);
 235 }
 236
 237 static void reply_nt1_orig(struct smbsrv_request *req)
 238 {
 239         /* Create a token value and add it to the outgoing packet. */
 240         if (req->smb_conn->negotiate.encrypted_passwords) {
 241                 req_grow_data(req, 8);
 242                 /* note that we do not send a challenge at all if
 243                    we are using plaintext */
 244                 get_challenge(req->smb_conn, req->out.ptr);
 245                 req->out.ptr += 8;
 246                 SCVAL(req->out.vwv+1, VWV(16), 8);
 247         }
 248         req_push_str(req, NULL, lpcfg_workgroup(req->smb_conn->lp_ctx), -1, STR_UNICODE|STR_TERMINATE|STR_NOALIGN);
 249         req_push_str(req, NULL, lpcfg_netbios_name(req->smb_conn->lp_ctx), -1, STR_UNICODE|STR_TERMINATE|STR_NOALIGN);
 250         DEBUG(3,("not using extended security (SPNEGO or NTLMSSP)\n"));
 251 }
 252
 253 /****************************************************************************
 254  Reply for the nt protocol.
 255 ****************************************************************************/
 256 static void reply_nt1(struct smbsrv_request *req, uint16_t choice)
 257 {
 258         /* dual names + lock_and_read + nt SMBs + remote API calls */
 259         int capabilities;
 260         int secword=0;
 261         time_t t = req->request_time.tv_sec;
 262         NTTIME nttime;
 263         bool negotiate_spnego = false;
 264         char *large_test_path;
 265
 266         unix_to_nt_time(&nttime, t);
 267
 268         capabilities =
 269                 CAP_NT_FIND | CAP_LOCK_AND_READ |
 270                 CAP_LEVEL_II_OPLOCKS | CAP_NT_SMBS | CAP_RPC_REMOTE_APIS;
 271
 272         req->smb_conn->negotiate.encrypted_passwords = lpcfg_encrypt_passwords(req->smb_conn->lp_ctx);
 273
 274         /* do spnego in user level security if the client
 275            supports it and we can do encrypted passwords */
 276
 277         if (req->smb_conn->negotiate.encrypted_passwords &&
 278             lpcfg_use_spnego(req->smb_conn->lp_ctx) &&
 279             (req->flags2 & FLAGS2_EXTENDED_SECURITY)) {
 280                 negotiate_spnego = true;
 281                 capabilities |= CAP_EXTENDED_SECURITY;
 282         }
 283
 284         if (lpcfg_large_readwrite(req->smb_conn->lp_ctx)) {
 285                 capabilities |= CAP_LARGE_READX | CAP_LARGE_WRITEX | CAP_W2K_SMBS;
 286         }
 287
 288         large_test_path = lpcfg_lock_path(req, req->smb_conn->lp_ctx, "large_test.dat");
 289         if (large_file_support(large_test_path)) {
 290                 capabilities |= CAP_LARGE_FILES;
 291         }
 292
 293         if (!lpcfg_async_smb_echo_handler(req->smb_conn->lp_ctx) &&
 294             lpcfg_read_raw(req->smb_conn->lp_ctx) &&
 295             lpcfg_write_raw(req->smb_conn->lp_ctx)) {
 296                 capabilities |= CAP_RAW_MODE;
 297         }
 298
 299         /* allow for disabling unicode */
 300         if (lpcfg_unicode(req->smb_conn->lp_ctx)) {
 301                 capabilities |= CAP_UNICODE;
 302         }
 303
 304         if (lpcfg_nt_status_support(req->smb_conn->lp_ctx)) {
 305                 capabilities |= CAP_STATUS32;
 306         }
 307
 308         if (lpcfg_host_msdfs(req->smb_conn->lp_ctx)) {
 309                 capabilities |= CAP_DFS;
 310         }
 311
 312         secword |= NEGOTIATE_SECURITY_USER_LEVEL;
 313
 314         if (req->smb_conn->negotiate.encrypted_passwords) {
 315                 secword |= NEGOTIATE_SECURITY_CHALLENGE_RESPONSE;
 316         }
 317
 318         if (req->smb_conn->signing.allow_smb_signing) {
 319                 secword |= NEGOTIATE_SECURITY_SIGNATURES_ENABLED;
 320         }
 321
 322         if (req->smb_conn->signing.mandatory_signing) {
 323                 secword |= NEGOTIATE_SECURITY_SIGNATURES_REQUIRED;
 324         }
 325
 326         req->smb_conn->negotiate.protocol = PROTOCOL_NT1;
 327
 328         smbsrv_setup_reply(req, 17, 0);
 329
 330         SSVAL(req->out.vwv, VWV(0), choice);
 331         SCVAL(req->out.vwv, VWV(1), secword);
 332
 333         /* notice the strange +1 on vwv here? That's because
 334            this is the one and only SMB packet that is malformed in
 335            the specification - all the command words after the secword
 336            are offset by 1 byte */
 337         SSVAL(req->out.vwv+1, VWV(1), lpcfg_max_mux(req->smb_conn->lp_ctx));
 338         SSVAL(req->out.vwv+1, VWV(2), 1); /* num vcs */
 339         SIVAL(req->out.vwv+1, VWV(3), req->smb_conn->negotiate.max_recv);
 340         SIVAL(req->out.vwv+1, VWV(5), 0x10000); /* raw size. full 64k */
 341         SIVAL(req->out.vwv+1, VWV(7), req->smb_conn->connection->server_id.pid); /* session key */
 342
 343         SIVAL(req->out.vwv+1, VWV(9), capabilities);
 344         push_nttime(req->out.vwv+1, VWV(11), nttime);
 345         SSVALS(req->out.vwv+1,VWV(15), req->smb_conn->negotiate.zone_offset/60);
 346
 347         if (!negotiate_spnego) {
 348                 reply_nt1_orig(req);
 349         } else {
 350                 struct cli_credentials *server_credentials;
 351                 struct gensec_security *gensec_security;
 352                 DATA_BLOB null_data_blob = data_blob(NULL, 0);
 353                 DATA_BLOB blob;
 354                 const char *oid;
 355                 NTSTATUS nt_status;
 356
 357                 server_credentials
 358                         = cli_credentials_init(req);
 359                 if (!server_credentials) {
 360                         smbsrv_terminate_connection(req->smb_conn, "Failed to init server credentials\n");
 361                         return;
 362                 }
 363
 364                 cli_credentials_set_conf(server_credentials, req->smb_conn->lp_ctx);
 365                 nt_status = cli_credentials_set_machine_account(server_credentials, req->smb_conn->lp_ctx);
 366                 if (!NT_STATUS_IS_OK(nt_status)) {
 367                         DEBUG(10, ("Failed to obtain server credentials, perhaps a standalone server?: %s\n", nt_errstr(nt_status)));
 368                         talloc_free(server_credentials);
 369                         server_credentials = NULL;
 370                 }
 371
 372                 nt_status = samba_server_gensec_start(req,
 373                                                       req->smb_conn->connection->event.ctx,
 374                                                       req->smb_conn->connection->msg_ctx,
 375                                                       req->smb_conn->lp_ctx,
 376                                                       server_credentials,
 377                                                       "cifs",
 378                                                       &gensec_security);
 379
 380                 if (!NT_STATUS_IS_OK(nt_status)) {
 381                         DEBUG(0, ("Failed to start GENSEC: %s\n", nt_errstr(nt_status)));
 382                         smbsrv_terminate_connection(req->smb_conn, "Failed to start GENSEC\n");
 383                         return;
 384                 }
 385
 386                 if (req->smb_conn->negotiate.auth_context) {
 387                         smbsrv_terminate_connection(req->smb_conn, "reply_nt1: is this a secondary negprot?  auth_context is non-NULL!\n");
 388                         return;
 389                 }
 390                 req->smb_conn->negotiate.server_credentials = talloc_reparent(req, req->smb_conn, server_credentials);
 391
 392                 oid = GENSEC_OID_SPNEGO;
 393                 nt_status = gensec_start_mech_by_oid(gensec_security, oid);
 394
 395                 if (NT_STATUS_IS_OK(nt_status)) {
 396                         /* Get and push the proposed OID list into the packets */
 397                         nt_status = gensec_update(gensec_security, req, req->smb_conn->connection->event.ctx, null_data_blob, &blob);
 398
 399                         if (!NT_STATUS_IS_OK(nt_status) && !NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 400                                 DEBUG(1, ("Failed to get SPNEGO to give us the first token: %s\n", nt_errstr(nt_status)));
 401                         }
 402                 }
 403
 404                 if (NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 405                         DEBUG(3,("using SPNEGO\n"));
 406                 } else {
 407                         DEBUG(5, ("Failed to start SPNEGO, falling back to NTLMSSP only: %s\n", nt_errstr(nt_status)));
 408                         oid = GENSEC_OID_NTLMSSP;
 409                         nt_status = gensec_start_mech_by_oid(gensec_security, oid);
 410
 411                         if (!NT_STATUS_IS_OK(nt_status)) {
 412                                 DEBUG(0, ("Failed to start SPNEGO as well as NTLMSSP fallback: %s\n", nt_errstr(nt_status)));
 413                                 reply_nt1_orig(req);
 414                                 return;
 415                         }
 416                         /* NTLMSSP is a client-first exchange */
 417                         blob = data_blob(NULL, 0);
 418                         DEBUG(3,("using raw-NTLMSSP\n"));
 419                 }
 420
 421                 req->smb_conn->negotiate.oid = oid;
 422
 423                 req_grow_data(req, blob.length + 16);
 424                 /* a NOT very random guid, perhaps we should get it
 425                  * from the credentials (kitchen sink...) */
 426                 memset(req->out.ptr, '\0', 16);
 427                 req->out.ptr += 16;
 428
 429                 memcpy(req->out.ptr, blob.data, blob.length);
 430                 SCVAL(req->out.vwv+1, VWV(16), blob.length + 16);
 431                 req->out.ptr += blob.length;
 432         }
 433
 434         smbsrv_send_reply_nosign(req);
 435 }
 436
 437 /****************************************************************************
 438  Reply for the SMB2 2.001 protocol
 439 ****************************************************************************/
 440 static void reply_smb2(struct smbsrv_request *req, uint16_t choice)
 441 {
 442         struct smbsrv_connection *smb_conn = req->smb_conn;
 443         NTSTATUS status;
 444
 445         talloc_free(smb_conn->sessions.idtree_vuid);
 446         ZERO_STRUCT(smb_conn->sessions);
 447         talloc_free(smb_conn->smb_tcons.idtree_tid);
 448         ZERO_STRUCT(smb_conn->smb_tcons);
 449         ZERO_STRUCT(smb_conn->signing);
 450
 451         /* reply with a SMB2 packet */
 452         status = smbsrv_init_smb2_connection(smb_conn);
 453         if (!NT_STATUS_IS_OK(status)) {
 454                 smbsrv_terminate_connection(smb_conn, nt_errstr(status));
 455                 talloc_free(req);
 456                 return;
 457         }
 458         packet_set_callback(smb_conn->packet, smbsrv_recv_smb2_request);
 459         smb2srv_reply_smb_negprot(req);
 460         req = NULL;
 461 }
 462
 463 /* List of supported protocols, most desired first */
 464 static const struct {
 465         const char *proto_name;
 466         const char *short_name;
 467         void (*proto_reply_fn)(struct smbsrv_request *req, uint16_t choice);
 468         int protocol_level;
 469 } supported_protocols[] = {
 470         {"SMB 2.002",                   "SMB2",         reply_smb2,     PROTOCOL_SMB2_02},
 471         {"NT LANMAN 1.0",               "NT1",          reply_nt1,      PROTOCOL_NT1},
 472         {"NT LM 0.12",                  "NT1",          reply_nt1,      PROTOCOL_NT1},
 473         {"LANMAN2.1",                   "LANMAN2",      reply_lanman2,  PROTOCOL_LANMAN2},
 474         {"LM1.2X002",                   "LANMAN2",      reply_lanman2,  PROTOCOL_LANMAN2},
 475         {"Samba",                       "LANMAN2",      reply_lanman2,  PROTOCOL_LANMAN2},
 476         {"DOS LM1.2X002",               "LANMAN2",      reply_lanman2,  PROTOCOL_LANMAN2},
 477         {"Windows for Workgroups 3.1a", "LANMAN1",      reply_lanman1,  PROTOCOL_LANMAN1},
 478         {"LANMAN1.0",                   "LANMAN1",      reply_lanman1,  PROTOCOL_LANMAN1},
 479         {"MICROSOFT NETWORKS 3.0",      "LANMAN1",      reply_lanman1,  PROTOCOL_LANMAN1},
 480         {"MICROSOFT NETWORKS 1.03",     "COREPLUS",     reply_coreplus, PROTOCOL_COREPLUS},
 481         {"PC NETWORK PROGRAM 1.0",      "CORE",         reply_corep,    PROTOCOL_CORE},
 482         {NULL,NULL,NULL,0},
 483 };
 484
 485 /****************************************************************************
 486  Reply to a negprot.
 487 ****************************************************************************/
 488
 489 void smbsrv_reply_negprot(struct smbsrv_request *req)
 490 {
 491         int protocol;
 492         uint8_t *p;
 493         uint32_t protos_count = 0;
 494         char **protos = NULL;
 495
 496         if (req->smb_conn->negotiate.done_negprot) {
 497                 smbsrv_terminate_connection(req->smb_conn, "multiple negprot's are not permitted");
 498                 return;
 499         }
 500         req->smb_conn->negotiate.done_negprot = true;
 501
 502         p = req->in.data;
 503         while (true) {
 504                 size_t len;
 505
 506                 protos = talloc_realloc(req, protos, char *, protos_count + 1);
 507                 if (!protos) {
 508                         smbsrv_terminate_connection(req->smb_conn, nt_errstr(NT_STATUS_NO_MEMORY));
 509                         return;
 510                 }
 511                 protos[protos_count] = NULL;
 512                 len = req_pull_ascii4(&req->in.bufinfo, (const char **)&protos[protos_count], p, STR_ASCII|STR_TERMINATE);
 513                 p += len;
 514                 if (len == 0 || !protos[protos_count]) break;
 515
 516                 DEBUG(5,("Requested protocol [%d][%s]\n", protos_count, protos[protos_count]));
 517                 protos_count++;
 518         }
 519
 520         /* Check for protocols, most desirable first */
 521         for (protocol = 0; supported_protocols[protocol].proto_name; protocol++) {
 522                 int i;
 523
 524                 if (supported_protocols[protocol].protocol_level > lpcfg_server_max_protocol(req->smb_conn->lp_ctx))
 525                         continue;
 526                 if (supported_protocols[protocol].protocol_level < lpcfg_server_min_protocol(req->smb_conn->lp_ctx))
 527                         continue;
 528
 529                 for (i = 0; i < protos_count; i++) {
 530                         if (strcmp(supported_protocols[protocol].proto_name, protos[i]) != 0) continue;
 531
 532                         supported_protocols[protocol].proto_reply_fn(req, i);
 533                         DEBUG(3,("Selected protocol [%d][%s]\n",
 534                                 i, supported_protocols[protocol].proto_name));
 535                         return;
 536                 }
 537         }
 538
 539         smbsrv_terminate_connection(req->smb_conn, "No protocol supported !");
 540 }