source4/auth/gensec/schannel.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    dcerpc schannel operations
   5
   6    Copyright (C) Andrew Tridgell 2004
   7    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2004-2005
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  21 */
  22
  23 #include "includes.h"
  24 #include "librpc/gen_ndr/ndr_schannel.h"
  25 #include "auth/auth.h"
  26 #include "auth/credentials/credentials.h"
  27 #include "auth/gensec/gensec.h"
  28 #include "auth/gensec/gensec_proto.h"
  29 #include "../libcli/auth/schannel.h"
  30 #include "librpc/rpc/dcerpc.h"
  31 #include "param/param.h"
  32 #include "auth/gensec/schannel.h"
  33 #include "auth/gensec/gensec_toplevel_proto.h"
  34
  35 _PUBLIC_ NTSTATUS gensec_schannel_init(void);
  36
  37 static size_t schannel_sig_size(struct gensec_security *gensec_security, size_t data_size)
  38 {
  39         struct schannel_state *state = (struct schannel_state *)gensec_security->private_data;
  40         uint32_t sig_size;
  41
  42         sig_size = netsec_outgoing_sig_size(state);
  43
  44         return sig_size;
  45 }
  46
  47 static NTSTATUS schannel_session_key(struct gensec_security *gensec_security,
  48                                      TALLOC_CTX *mem_ctx,
  49                                      DATA_BLOB *session_key)
  50 {
  51         return NT_STATUS_NOT_IMPLEMENTED;
  52 }
  53
  54 static NTSTATUS schannel_update(struct gensec_security *gensec_security, TALLOC_CTX *out_mem_ctx,
  55                                 struct tevent_context *ev,
  56                                 const DATA_BLOB in, DATA_BLOB *out)
  57 {
  58         struct schannel_state *state = (struct schannel_state *)gensec_security->private_data;
  59         NTSTATUS status;
  60         enum ndr_err_code ndr_err;
  61         struct NL_AUTH_MESSAGE bind_schannel;
  62         struct NL_AUTH_MESSAGE bind_schannel_ack;
  63         struct netlogon_creds_CredentialState *creds;
  64         const char *workstation;
  65         const char *domain;
  66
  67         *out = data_blob(NULL, 0);
  68
  69         switch (gensec_security->gensec_role) {
  70         case GENSEC_CLIENT:
  71                 if (state->state != SCHANNEL_STATE_START) {
  72                         /* we could parse the bind ack, but we don't know what it is yet */
  73                         return NT_STATUS_OK;
  74                 }
  75
  76                 state->creds = cli_credentials_get_netlogon_creds(gensec_security->credentials);
  77                 if (state->creds == NULL) {
  78                         return NT_STATUS_INVALID_PARAMETER_MIX;
  79                 }
  80                 /*
  81                  * We need to create a reference here or we don't get
  82                  * updates performed on the credentials if we create a
  83                  * copy.
  84                  */
  85                 state->creds = talloc_reference(state, state->creds);
  86                 if (state->creds == NULL) {
  87                         return NT_STATUS_NO_MEMORY;
  88                 }
  89
  90                 bind_schannel.MessageType = NL_NEGOTIATE_REQUEST;
  91 #if 0
  92                 /* to support this we'd need to have access to the full domain name */
  93                 /* 0x17, 23 */
  94                 bind_schannel.Flags = NL_FLAG_OEM_NETBIOS_DOMAIN_NAME |
  95                                       NL_FLAG_OEM_NETBIOS_COMPUTER_NAME |
  96                                       NL_FLAG_UTF8_DNS_DOMAIN_NAME |
  97                                       NL_FLAG_UTF8_NETBIOS_COMPUTER_NAME;
  98                 bind_schannel.oem_netbios_domain.a = cli_credentials_get_domain(gensec_security->credentials);
  99                 bind_schannel.oem_netbios_computer.a = cli_credentials_get_workstation(gensec_security->credentials);
 100                 bind_schannel.utf8_dns_domain = cli_credentials_get_realm(gensec_security->credentials);
 101                 /* w2k3 refuses us if we use the full DNS workstation?
 102                  why? perhaps because we don't fill in the dNSHostName
 103                  attribute in the machine account? */
 104                 bind_schannel.utf8_netbios_computer = cli_credentials_get_workstation(gensec_security->credentials);
 105 #else
 106                 bind_schannel.Flags = NL_FLAG_OEM_NETBIOS_DOMAIN_NAME |
 107                                       NL_FLAG_OEM_NETBIOS_COMPUTER_NAME;
 108                 bind_schannel.oem_netbios_domain.a = cli_credentials_get_domain(gensec_security->credentials);
 109                 bind_schannel.oem_netbios_computer.a = cli_credentials_get_workstation(gensec_security->credentials);
 110 #endif
 111
 112                 ndr_err = ndr_push_struct_blob(out, out_mem_ctx, &bind_schannel,
 113                                                (ndr_push_flags_fn_t)ndr_push_NL_AUTH_MESSAGE);
 114                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 115                         status = ndr_map_error2ntstatus(ndr_err);
 116                         DEBUG(3, ("Could not create schannel bind: %s\n",
 117                                   nt_errstr(status)));
 118                         return status;
 119                 }
 120
 121                 state->state = SCHANNEL_STATE_UPDATE_1;
 122
 123                 return NT_STATUS_MORE_PROCESSING_REQUIRED;
 124         case GENSEC_SERVER:
 125
 126                 if (state->state != SCHANNEL_STATE_START) {
 127                         /* no third leg on this protocol */
 128                         return NT_STATUS_INVALID_PARAMETER;
 129                 }
 130
 131                 /* parse the schannel startup blob */
 132                 ndr_err = ndr_pull_struct_blob(&in, out_mem_ctx, &bind_schannel,
 133                         (ndr_pull_flags_fn_t)ndr_pull_NL_AUTH_MESSAGE);
 134                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 135                         status = ndr_map_error2ntstatus(ndr_err);
 136                         DEBUG(3, ("Could not parse incoming schannel bind: %s\n",
 137                                   nt_errstr(status)));
 138                         return status;
 139                 }
 140
 141                 if (bind_schannel.Flags & NL_FLAG_OEM_NETBIOS_DOMAIN_NAME) {
 142                         domain = bind_schannel.oem_netbios_domain.a;
 143                         if (strcasecmp_m(domain, lpcfg_workgroup(gensec_security->settings->lp_ctx)) != 0) {
 144                                 DEBUG(3, ("Request for schannel to incorrect domain: %s != our domain %s\n",
 145                                           domain, lpcfg_workgroup(gensec_security->settings->lp_ctx)));
 146                                 return NT_STATUS_LOGON_FAILURE;
 147                         }
 148                 } else if (bind_schannel.Flags & NL_FLAG_UTF8_DNS_DOMAIN_NAME) {
 149                         domain = bind_schannel.utf8_dns_domain.u;
 150                         if (strcasecmp_m(domain, lpcfg_dnsdomain(gensec_security->settings->lp_ctx)) != 0) {
 151                                 DEBUG(3, ("Request for schannel to incorrect domain: %s != our domain %s\n",
 152                                           domain, lpcfg_dnsdomain(gensec_security->settings->lp_ctx)));
 153                                 return NT_STATUS_LOGON_FAILURE;
 154                         }
 155                 } else {
 156                         DEBUG(3, ("Request for schannel to without domain\n"));
 157                         return NT_STATUS_LOGON_FAILURE;
 158                 }
 159
 160                 if (bind_schannel.Flags & NL_FLAG_OEM_NETBIOS_COMPUTER_NAME) {
 161                         workstation = bind_schannel.oem_netbios_computer.a;
 162                 } else if (bind_schannel.Flags & NL_FLAG_UTF8_NETBIOS_COMPUTER_NAME) {
 163                         workstation = bind_schannel.utf8_netbios_computer.u;
 164                 } else {
 165                         DEBUG(3, ("Request for schannel to without netbios workstation\n"));
 166                         return NT_STATUS_LOGON_FAILURE;
 167                 }
 168
 169                 status = schannel_get_creds_state(out_mem_ctx,
 170                                                   gensec_security->settings->lp_ctx,
 171                                                   workstation, &creds);
 172                 if (!NT_STATUS_IS_OK(status)) {
 173                         DEBUG(3, ("Could not find session key for attempted schannel connection from %s: %s\n",
 174                                   workstation, nt_errstr(status)));
 175                         if (NT_STATUS_EQUAL(status, NT_STATUS_INVALID_HANDLE)) {
 176                                 return NT_STATUS_LOGON_FAILURE;
 177                         }
 178                         return status;
 179                 }
 180
 181                 state->creds = talloc_steal(state, creds);
 182
 183                 bind_schannel_ack.MessageType = NL_NEGOTIATE_RESPONSE;
 184                 bind_schannel_ack.Flags = 0;
 185                 bind_schannel_ack.Buffer.dummy = 0x6c0000; /* actually I think
 186                                                             * this does not have
 187                                                             * any meaning here
 188                                                             * - gd */
 189
 190                 ndr_err = ndr_push_struct_blob(out, out_mem_ctx, &bind_schannel_ack,
 191                                                (ndr_push_flags_fn_t)ndr_push_NL_AUTH_MESSAGE);
 192                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 193                         status = ndr_map_error2ntstatus(ndr_err);
 194                         DEBUG(3, ("Could not return schannel bind ack for client %s: %s\n",
 195                                   workstation, nt_errstr(status)));
 196                         return status;
 197                 }
 198
 199                 state->state = SCHANNEL_STATE_UPDATE_1;
 200
 201                 return NT_STATUS_OK;
 202         }
 203         return NT_STATUS_INVALID_PARAMETER;
 204 }
 205
 206 /**
 207  * Return the struct netlogon_creds_CredentialState.
 208  *
 209  * Make sure not to call this unless gensec is using schannel...
 210  */
 211
 212 /* TODO: make this non-public */
 213
 214 _PUBLIC_ NTSTATUS dcerpc_schannel_creds(struct gensec_security *gensec_security,
 215                                         TALLOC_CTX *mem_ctx,
 216                                         struct netlogon_creds_CredentialState **creds)
 217 {
 218         struct schannel_state *state = talloc_get_type(gensec_security->private_data, struct schannel_state);
 219
 220         *creds = talloc_reference(mem_ctx, state->creds);
 221         if (!*creds) {
 222                 return NT_STATUS_NO_MEMORY;
 223         }
 224         return NT_STATUS_OK;
 225 }
 226
 227
 228 /**
 229  * Returns anonymous credentials for schannel, matching Win2k3.
 230  *
 231  */
 232
 233 static NTSTATUS schannel_session_info(struct gensec_security *gensec_security,
 234                                       TALLOC_CTX *mem_ctx,
 235                                       struct auth_session_info **_session_info)
 236 {
 237         return auth_anonymous_session_info(mem_ctx, gensec_security->settings->lp_ctx, _session_info);
 238 }
 239
 240 static NTSTATUS schannel_start(struct gensec_security *gensec_security)
 241 {
 242         struct schannel_state *state;
 243
 244         state = talloc_zero(gensec_security, struct schannel_state);
 245         if (!state) {
 246                 return NT_STATUS_NO_MEMORY;
 247         }
 248
 249         state->state = SCHANNEL_STATE_START;
 250         gensec_security->private_data = state;
 251
 252         return NT_STATUS_OK;
 253 }
 254
 255 static NTSTATUS schannel_server_start(struct gensec_security *gensec_security)
 256 {
 257         NTSTATUS status;
 258         struct schannel_state *state;
 259
 260         status = schannel_start(gensec_security);
 261         if (!NT_STATUS_IS_OK(status)) {
 262                 return status;
 263         }
 264
 265         state = (struct schannel_state *)gensec_security->private_data;
 266         state->initiator = false;
 267
 268         return NT_STATUS_OK;
 269 }
 270
 271 static NTSTATUS schannel_client_start(struct gensec_security *gensec_security)
 272 {
 273         NTSTATUS status;
 274         struct schannel_state *state;
 275
 276         status = schannel_start(gensec_security);
 277         if (!NT_STATUS_IS_OK(status)) {
 278                 return status;
 279         }
 280
 281         state = (struct schannel_state *)gensec_security->private_data;
 282         state->initiator = true;
 283
 284         return NT_STATUS_OK;
 285 }
 286
 287
 288 static bool schannel_have_feature(struct gensec_security *gensec_security,
 289                                          uint32_t feature)
 290 {
 291         if (feature & (GENSEC_FEATURE_SIGN |
 292                        GENSEC_FEATURE_SEAL)) {
 293                 return true;
 294         }
 295         if (feature & GENSEC_FEATURE_DCE_STYLE) {
 296                 return true;
 297         }
 298         if (feature & GENSEC_FEATURE_ASYNC_REPLIES) {
 299                 return true;
 300         }
 301         return false;
 302 }
 303
 304 /*
 305   unseal a packet
 306 */
 307 static NTSTATUS schannel_unseal_packet(struct gensec_security *gensec_security,
 308                                        uint8_t *data, size_t length,
 309                                        const uint8_t *whole_pdu, size_t pdu_length,
 310                                        const DATA_BLOB *sig)
 311 {
 312         struct schannel_state *state =
 313                 talloc_get_type(gensec_security->private_data,
 314                                 struct schannel_state);
 315
 316         return netsec_incoming_packet(state, true,
 317                                       discard_const_p(uint8_t, data),
 318                                       length, sig);
 319 }
 320
 321 /*
 322   check the signature on a packet
 323 */
 324 static NTSTATUS schannel_check_packet(struct gensec_security *gensec_security,
 325                                       const uint8_t *data, size_t length,
 326                                       const uint8_t *whole_pdu, size_t pdu_length,
 327                                       const DATA_BLOB *sig)
 328 {
 329         struct schannel_state *state =
 330                 talloc_get_type(gensec_security->private_data,
 331                                 struct schannel_state);
 332
 333         return netsec_incoming_packet(state, false,
 334                                       discard_const_p(uint8_t, data),
 335                                       length, sig);
 336 }
 337 /*
 338   seal a packet
 339 */
 340 static NTSTATUS schannel_seal_packet(struct gensec_security *gensec_security,
 341                                      TALLOC_CTX *mem_ctx,
 342                                      uint8_t *data, size_t length,
 343                                      const uint8_t *whole_pdu, size_t pdu_length,
 344                                      DATA_BLOB *sig)
 345 {
 346         struct schannel_state *state =
 347                 talloc_get_type(gensec_security->private_data,
 348                                 struct schannel_state);
 349
 350         return netsec_outgoing_packet(state, mem_ctx, true,
 351                                       data, length, sig);
 352 }
 353
 354 /*
 355   sign a packet
 356 */
 357 static NTSTATUS schannel_sign_packet(struct gensec_security *gensec_security,
 358                                      TALLOC_CTX *mem_ctx,
 359                                      const uint8_t *data, size_t length,
 360                                      const uint8_t *whole_pdu, size_t pdu_length,
 361                                      DATA_BLOB *sig)
 362 {
 363         struct schannel_state *state =
 364                 talloc_get_type(gensec_security->private_data,
 365                                 struct schannel_state);
 366
 367         return netsec_outgoing_packet(state, mem_ctx, false,
 368                                       discard_const_p(uint8_t, data),
 369                                       length, sig);
 370 }
 371
 372 static const struct gensec_security_ops gensec_schannel_security_ops = {
 373         .name           = "schannel",
 374         .auth_type      = DCERPC_AUTH_TYPE_SCHANNEL,
 375         .client_start   = schannel_client_start,
 376         .server_start   = schannel_server_start,
 377         .update         = schannel_update,
 378         .seal_packet    = schannel_seal_packet,
 379         .sign_packet    = schannel_sign_packet,
 380         .check_packet   = schannel_check_packet,
 381         .unseal_packet  = schannel_unseal_packet,
 382         .session_key    = schannel_session_key,
 383         .session_info   = schannel_session_info,
 384         .sig_size       = schannel_sig_size,
 385         .have_feature   = schannel_have_feature,
 386         .enabled        = true,
 387         .priority       = GENSEC_SCHANNEL
 388 };
 389
 390 _PUBLIC_ NTSTATUS gensec_schannel_init(void)
 391 {
 392         NTSTATUS ret;
 393         ret = gensec_register(&gensec_schannel_security_ops);
 394         if (!NT_STATUS_IS_OK(ret)) {
 395                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
 396                         gensec_schannel_security_ops.name));
 397                 return ret;
 398         }
 399
 400         return ret;
 401 }