source4/libcli/composite/sesssetup.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    Copyright (C) Andrew Tridgell 2005
   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   a composite API for making handling a generic async session setup
  22 */
  23
  24 #include "includes.h"
  25 #include "libcli/raw/libcliraw.h"
  26 #include "libcli/composite/composite.h"
  27 #include "auth/auth.h"
  28
  29
  30 struct sesssetup_state {
  31         union smb_sesssetup setup;
  32         NTSTATUS session_key_err;
  33         struct smb_composite_sesssetup *io;
  34         struct smbcli_request *req;
  35 };
  36
  37
  38 /*
  39   form an encrypted lanman password from a plaintext password
  40   and the server supplied challenge
  41 */
  42 static DATA_BLOB lanman_blob(TALLOC_CTX *mem_ctx, const char *pass, DATA_BLOB challenge)
  43 {
  44         DATA_BLOB blob = data_blob_talloc(mem_ctx, NULL, 24);
  45         SMBencrypt(pass, challenge.data, blob.data);
  46         return blob;
  47 }
  48
  49 /*
  50   form an encrypted NT password from a plaintext password
  51   and the server supplied challenge
  52 */
  53 static DATA_BLOB nt_blob(TALLOC_CTX *mem_ctx, const char *pass, DATA_BLOB challenge)
  54 {
  55         DATA_BLOB blob = data_blob_talloc(mem_ctx, NULL, 24);
  56         SMBNTencrypt(pass, challenge.data, blob.data);
  57         return blob;
  58 }
  59
  60 /*
  61   store the user session key for a transport
  62 */
  63 static void set_user_session_key(struct smbcli_session *session,
  64                                  const DATA_BLOB *session_key)
  65 {
  66         session->user_session_key = data_blob_talloc(session,
  67                                                      session_key->data,
  68                                                      session_key->length);
  69 }
  70
  71 /*
  72   setup signing for a NT1 style session setup
  73 */
  74 static void use_nt1_session_keys(struct smbcli_session *session,
  75                                  const char *password, const DATA_BLOB *nt_response)
  76 {
  77         struct smbcli_transport *transport = session->transport;
  78         uint8_t nt_hash[16];
  79         DATA_BLOB session_key = data_blob_talloc(session, NULL, 16);
  80
  81         E_md4hash(password, nt_hash);
  82         SMBsesskeygen_ntv1(nt_hash, session_key.data);
  83
  84         smbcli_transport_simple_set_signing(transport, session_key, *nt_response);
  85
  86         set_user_session_key(session, &session_key);
  87         data_blob_free(&session_key);
  88 }
  89
  90
  91 /*
  92   handler for completion of a smbcli_request sub-request
  93 */
  94 static void request_handler(struct smbcli_request *req)
  95 {
  96         struct smbcli_composite *c = req->async.private;
  97         struct sesssetup_state *state = c->private;
  98         struct smbcli_session *session = req->session;
  99         DATA_BLOB session_key = data_blob(NULL, 0);
 100         DATA_BLOB null_data_blob = data_blob(NULL, 0);
 101
 102         c->status = smb_raw_session_setup_recv(req, state, &state->setup);
 103
 104         switch (state->setup.old.level) {
 105         case RAW_SESSSETUP_OLD:
 106                 state->io->out.vuid = state->setup.old.out.vuid;
 107                 break;
 108
 109         case RAW_SESSSETUP_NT1:
 110                 state->io->out.vuid = state->setup.nt1.out.vuid;
 111                 break;
 112
 113         case RAW_SESSSETUP_SPNEGO:
 114                 session->vuid = state->io->out.vuid = state->setup.spnego.out.vuid;
 115                 if (!NT_STATUS_EQUAL(c->status, NT_STATUS_MORE_PROCESSING_REQUIRED) &&
 116                     !NT_STATUS_IS_OK(c->status)) {
 117                         break;
 118                 }
 119                 c->status = gensec_update(session->gensec, state,
 120                                           state->setup.spnego.out.secblob,
 121                                           &state->setup.spnego.in.secblob);
 122                 if (!NT_STATUS_EQUAL(c->status, NT_STATUS_MORE_PROCESSING_REQUIRED) &&
 123                     !NT_STATUS_IS_OK(c->status)) {
 124                         break;
 125                 }
 126                 if (state->setup.spnego.in.secblob.length == 0) {
 127                         break;
 128                 }
 129
 130                 /* we need to do another round of session setup. We keep going until both sides
 131                    are happy */
 132                 state->session_key_err = gensec_session_key(session->gensec, &session_key);
 133                 if (NT_STATUS_IS_OK(state->session_key_err)) {
 134                         set_user_session_key(session, &session_key);
 135                         smbcli_transport_simple_set_signing(session->transport, session_key, null_data_blob);
 136                 }
 137
 138                 state->req = smb_raw_session_setup_send(session, &state->setup);
 139                 state->req->async.fn = request_handler;
 140                 state->req->async.private = c;
 141                 return;
 142         }
 143
 144         /* enforce the local signing required flag */
 145         if (NT_STATUS_IS_OK(c->status) && state->io->in.user && state->io->in.user[0]) {
 146                 if (!session->transport->negotiate.sign_info.doing_signing
 147                     && session->transport->negotiate.sign_info.mandatory_signing) {
 148                         DEBUG(0, ("SMB signing required, but server does not support it\n"));
 149                         c->status = NT_STATUS_ACCESS_DENIED;
 150                 }
 151         }
 152
 153         if (NT_STATUS_IS_OK(c->status)) {
 154                 c->state = SMBCLI_REQUEST_DONE;
 155         } else {
 156                 c->state = SMBCLI_REQUEST_ERROR;
 157         }
 158         if (c->async.fn) {
 159                 c->async.fn(c);
 160         }
 161 }
 162
 163
 164 /*
 165   send a nt1 style session setup
 166 */
 167 static struct smbcli_request *session_setup_nt1(struct smbcli_composite *c,
 168                                                 struct smbcli_session *session,
 169                                                 struct smb_composite_sesssetup *io)
 170 {
 171         struct sesssetup_state *state = c->private;
 172
 173         state->setup.nt1.level           = RAW_SESSSETUP_NT1;
 174         state->setup.nt1.in.bufsize      = session->transport->options.max_xmit;
 175         state->setup.nt1.in.mpx_max      = session->transport->options.max_mux;
 176         state->setup.nt1.in.vc_num       = 1;
 177         state->setup.nt1.in.sesskey      = io->in.sesskey;
 178         state->setup.nt1.in.capabilities = io->in.capabilities;
 179         state->setup.nt1.in.domain       = io->in.domain;
 180         state->setup.nt1.in.user         = io->in.user;
 181         state->setup.nt1.in.os           = "Unix";
 182         state->setup.nt1.in.lanman       = "Samba";
 183
 184         if (!io->in.password) {
 185                 state->setup.nt1.in.password1 = data_blob(NULL, 0);
 186                 state->setup.nt1.in.password2 = data_blob(NULL, 0);
 187         } else if (session->transport->negotiate.sec_mode &
 188                    NEGOTIATE_SECURITY_CHALLENGE_RESPONSE) {
 189                 state->setup.nt1.in.password1 = lanman_blob(state, io->in.password,
 190                                                             session->transport->negotiate.secblob);
 191                 state->setup.nt1.in.password2 = nt_blob(state, io->in.password,
 192                                                         session->transport->negotiate.secblob);
 193                 use_nt1_session_keys(session, io->in.password, &state->setup.nt1.in.password2);
 194         } else {
 195                 state->setup.nt1.in.password1 = data_blob_talloc(state, io->in.password, strlen(io->in.password));
 196                 state->setup.nt1.in.password2 = data_blob(NULL, 0);
 197         }
 198
 199         return smb_raw_session_setup_send(session, &state->setup);
 200 }
 201
 202
 203 /*
 204   old style session setup (pre NT1 protocol level)
 205 */
 206 static struct smbcli_request *session_setup_old(struct smbcli_composite *c,
 207                                                 struct smbcli_session *session,
 208                                                 struct smb_composite_sesssetup *io)
 209 {
 210         struct sesssetup_state *state = c->private;
 211
 212         state->setup.old.level      = RAW_SESSSETUP_OLD;
 213         state->setup.old.in.bufsize = session->transport->options.max_xmit;
 214         state->setup.old.in.mpx_max = session->transport->options.max_mux;
 215         state->setup.old.in.vc_num  = 1;
 216         state->setup.old.in.sesskey = io->in.sesskey;
 217         state->setup.old.in.domain  = io->in.domain;
 218         state->setup.old.in.user    = io->in.user;
 219         state->setup.old.in.os      = "Unix";
 220         state->setup.old.in.lanman  = "Samba";
 221
 222         if (!io->in.password) {
 223                 state->setup.old.in.password = data_blob(NULL, 0);
 224         } else if (session->transport->negotiate.sec_mode & NEGOTIATE_SECURITY_CHALLENGE_RESPONSE) {
 225                 state->setup.old.in.password = lanman_blob(state, io->in.password,
 226                                                            session->transport->negotiate.secblob);
 227         } else {
 228                 state->setup.old.in.password = data_blob_talloc(state,
 229                                                                 io->in.password,
 230                                                                 strlen(io->in.password));
 231         }
 232
 233         return smb_raw_session_setup_send(session, &state->setup);
 234 }
 235
 236
 237 /*
 238   old style session setup (pre NT1 protocol level)
 239 */
 240 static struct smbcli_request *session_setup_spnego(struct smbcli_composite *c,
 241                                                    struct smbcli_session *session,
 242                                                    struct smb_composite_sesssetup *io)
 243 {
 244         struct sesssetup_state *state = c->private;
 245         NTSTATUS status;
 246         DATA_BLOB session_key = data_blob(NULL, 0);
 247         DATA_BLOB null_data_blob = data_blob(NULL, 0);
 248         const char *chosen_oid = NULL;
 249
 250         state->setup.spnego.level           = RAW_SESSSETUP_SPNEGO;
 251         state->setup.spnego.in.bufsize      = session->transport->options.max_xmit;
 252         state->setup.spnego.in.mpx_max      = session->transport->options.max_mux;
 253         state->setup.spnego.in.vc_num       = 1;
 254         state->setup.spnego.in.sesskey      = io->in.sesskey;
 255         state->setup.spnego.in.capabilities = io->in.capabilities;
 256         state->setup.spnego.in.domain       = io->in.domain;
 257         state->setup.spnego.in.os           = "Unix";
 258         state->setup.spnego.in.lanman       = "Samba";
 259         state->setup.spnego.out.vuid        = session->vuid;
 260
 261         smbcli_temp_set_signing(session->transport);
 262
 263         status = gensec_client_start(session, &session->gensec);
 264         if (!NT_STATUS_IS_OK(status)) {
 265                 DEBUG(1, ("Failed to start GENSEC client mode: %s\n", nt_errstr(status)));
 266                 return NULL;
 267         }
 268
 269         gensec_want_feature(session->gensec, GENSEC_FEATURE_SESSION_KEY);
 270
 271         status = gensec_set_domain(session->gensec, io->in.domain);
 272         if (!NT_STATUS_IS_OK(status)) {
 273                 DEBUG(1, ("Failed to start set GENSEC client domain to %s: %s\n",
 274                           io->in.domain, nt_errstr(status)));
 275                 return NULL;
 276         }
 277
 278         status = gensec_set_username(session->gensec, io->in.user);
 279         if (!NT_STATUS_IS_OK(status)) {
 280                 DEBUG(1, ("Failed to start set GENSEC client username to %s: %s\n",
 281                           io->in.user, nt_errstr(status)));
 282                 return NULL;
 283         }
 284
 285         status = gensec_set_password(session->gensec, io->in.password);
 286         if (!NT_STATUS_IS_OK(status)) {
 287                 DEBUG(1, ("Failed to start set GENSEC client password: %s\n",
 288                           nt_errstr(status)));
 289                 return NULL;
 290         }
 291
 292         status = gensec_set_target_hostname(session->gensec, session->transport->socket->hostname);
 293         if (!NT_STATUS_IS_OK(status)) {
 294                 DEBUG(1, ("Failed to start set GENSEC target hostname: %s\n",
 295                           nt_errstr(status)));
 296                 return NULL;
 297         }
 298
 299         if (session->transport->negotiate.secblob.length) {
 300                 chosen_oid = GENSEC_OID_SPNEGO;
 301         } else {
 302                 /* without a sec blob, means raw NTLMSSP */
 303                 chosen_oid = GENSEC_OID_NTLMSSP;
 304         }
 305
 306         status = gensec_start_mech_by_oid(session->gensec, chosen_oid);
 307         if (!NT_STATUS_IS_OK(status)) {
 308                 DEBUG(1, ("Failed to start set GENSEC client SPNEGO mechanism %s: %s\n",
 309                           gensec_get_name_by_oid(chosen_oid), nt_errstr(status)));
 310                 return NULL;
 311         }
 312
 313         status = gensec_update(session->gensec, state,
 314                                session->transport->negotiate.secblob,
 315                                &state->setup.spnego.in.secblob);
 316         if (!NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 317                 DEBUG(1, ("Failed initial gensec_update with mechanism %s: %s\n",
 318                           gensec_get_name_by_oid(chosen_oid), nt_errstr(status)));
 319                 return NULL;
 320         }
 321
 322         state->session_key_err = gensec_session_key(session->gensec, &session_key);
 323         if (NT_STATUS_IS_OK(state->session_key_err)) {
 324                 smbcli_transport_simple_set_signing(session->transport, session_key, null_data_blob);
 325         }
 326
 327         return smb_raw_session_setup_send(session, &state->setup);
 328 }
 329
 330
 331 /*
 332   composite session setup function that hides the details of all the
 333   different session setup varients, including the multi-pass nature of
 334   the spnego varient
 335 */
 336 struct smbcli_composite *smb_composite_sesssetup_send(struct smbcli_session *session,
 337                                                       struct smb_composite_sesssetup *io)
 338 {
 339         struct smbcli_composite *c;
 340         struct sesssetup_state *state;
 341
 342         c = talloc_zero(session, struct smbcli_composite);
 343         if (c == NULL) goto failed;
 344
 345         state = talloc(c, struct sesssetup_state);
 346         if (state == NULL) goto failed;
 347
 348         state->io = io;
 349
 350         c->state = SMBCLI_REQUEST_SEND;
 351         c->private = state;
 352         c->event_ctx = session->transport->socket->event.ctx;
 353
 354         /* no session setup at all in earliest protocol varients */
 355         if (session->transport->negotiate.protocol < PROTOCOL_LANMAN1) {
 356                 ZERO_STRUCT(io->out);
 357                 c->state = SMBCLI_REQUEST_DONE;
 358                 return c;
 359         }
 360
 361         /* see what session setup interface we will use */
 362         if (session->transport->negotiate.protocol < PROTOCOL_NT1) {
 363                 state->req = session_setup_old(c, session, io);
 364         } else if (!session->transport->options.use_spnego ||
 365                    !(io->in.capabilities & CAP_EXTENDED_SECURITY)) {
 366                 state->req = session_setup_nt1(c, session, io);
 367         } else {
 368                 state->req = session_setup_spnego(c, session, io);
 369         }
 370
 371         if (state->req == NULL) goto failed;
 372
 373         state->req->async.fn = request_handler;
 374         state->req->async.private = c;
 375
 376         return c;
 377
 378 failed:
 379         talloc_free(c);
 380         return NULL;
 381 }
 382
 383
 384 /*
 385   receive a composite session setup reply
 386 */
 387 NTSTATUS smb_composite_sesssetup_recv(struct smbcli_composite *c)
 388 {
 389         NTSTATUS status;
 390         status = smb_composite_wait(c);
 391         talloc_free(c);
 392         return status;
 393 }
 394
 395 /*
 396   sync version of smb_composite_sesssetup
 397 */
 398 NTSTATUS smb_composite_sesssetup(struct smbcli_session *session, struct smb_composite_sesssetup *io)
 399 {
 400         struct smbcli_composite *c = smb_composite_sesssetup_send(session, io);
 401         return smb_composite_sesssetup_recv(c);
 402 }