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                 state->creds = netlogon_creds_copy(state, state->creds);
  81                 if (state->creds == NULL) {
  82                         return NT_STATUS_NO_MEMORY;
  83                 }
  84
  85                 bind_schannel.MessageType = NL_NEGOTIATE_REQUEST;
  86 #if 0
  87                 /* to support this we'd need to have access to the full domain name */
  88                 /* 0x17, 23 */
  89                 bind_schannel.Flags = NL_FLAG_OEM_NETBIOS_DOMAIN_NAME |
  90                                       NL_FLAG_OEM_NETBIOS_COMPUTER_NAME |
  91                                       NL_FLAG_UTF8_DNS_DOMAIN_NAME |
  92                                       NL_FLAG_UTF8_NETBIOS_COMPUTER_NAME;
  93                 bind_schannel.oem_netbios_domain.a = cli_credentials_get_domain(gensec_security->credentials);
  94                 bind_schannel.oem_netbios_computer.a = cli_credentials_get_workstation(gensec_security->credentials);
  95                 bind_schannel.utf8_dns_domain = cli_credentials_get_realm(gensec_security->credentials);
  96                 /* w2k3 refuses us if we use the full DNS workstation?
  97                  why? perhaps because we don't fill in the dNSHostName
  98                  attribute in the machine account? */
  99                 bind_schannel.utf8_netbios_computer = cli_credentials_get_workstation(gensec_security->credentials);
 100 #else
 101                 bind_schannel.Flags = NL_FLAG_OEM_NETBIOS_DOMAIN_NAME |
 102                                       NL_FLAG_OEM_NETBIOS_COMPUTER_NAME;
 103                 bind_schannel.oem_netbios_domain.a = cli_credentials_get_domain(gensec_security->credentials);
 104                 bind_schannel.oem_netbios_computer.a = cli_credentials_get_workstation(gensec_security->credentials);
 105 #endif
 106
 107                 ndr_err = ndr_push_struct_blob(out, out_mem_ctx, &bind_schannel,
 108                                                (ndr_push_flags_fn_t)ndr_push_NL_AUTH_MESSAGE);
 109                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 110                         status = ndr_map_error2ntstatus(ndr_err);
 111                         DEBUG(3, ("Could not create schannel bind: %s\n",
 112                                   nt_errstr(status)));
 113                         return status;
 114                 }
 115
 116                 state->state = SCHANNEL_STATE_UPDATE_1;
 117
 118                 return NT_STATUS_MORE_PROCESSING_REQUIRED;
 119         case GENSEC_SERVER:
 120
 121                 if (state->state != SCHANNEL_STATE_START) {
 122                         /* no third leg on this protocol */
 123                         return NT_STATUS_INVALID_PARAMETER;
 124                 }
 125
 126                 /* parse the schannel startup blob */
 127                 ndr_err = ndr_pull_struct_blob(&in, out_mem_ctx, &bind_schannel,
 128                         (ndr_pull_flags_fn_t)ndr_pull_NL_AUTH_MESSAGE);
 129                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 130                         status = ndr_map_error2ntstatus(ndr_err);
 131                         DEBUG(3, ("Could not parse incoming schannel bind: %s\n",
 132                                   nt_errstr(status)));
 133                         return status;
 134                 }
 135
 136                 if (bind_schannel.Flags & NL_FLAG_OEM_NETBIOS_DOMAIN_NAME) {
 137                         domain = bind_schannel.oem_netbios_domain.a;
 138                         if (strcasecmp_m(domain, lpcfg_workgroup(gensec_security->settings->lp_ctx)) != 0) {
 139                                 DEBUG(3, ("Request for schannel to incorrect domain: %s != our domain %s\n",
 140                                           domain, lpcfg_workgroup(gensec_security->settings->lp_ctx)));
 141                                 return NT_STATUS_LOGON_FAILURE;
 142                         }
 143                 } else if (bind_schannel.Flags & NL_FLAG_UTF8_DNS_DOMAIN_NAME) {
 144                         domain = bind_schannel.utf8_dns_domain.u;
 145                         if (strcasecmp_m(domain, lpcfg_dnsdomain(gensec_security->settings->lp_ctx)) != 0) {
 146                                 DEBUG(3, ("Request for schannel to incorrect domain: %s != our domain %s\n",
 147                                           domain, lpcfg_dnsdomain(gensec_security->settings->lp_ctx)));
 148                                 return NT_STATUS_LOGON_FAILURE;
 149                         }
 150                 } else {
 151                         DEBUG(3, ("Request for schannel to without domain\n"));
 152                         return NT_STATUS_LOGON_FAILURE;
 153                 }
 154
 155                 if (bind_schannel.Flags & NL_FLAG_OEM_NETBIOS_COMPUTER_NAME) {
 156                         workstation = bind_schannel.oem_netbios_computer.a;
 157                 } else if (bind_schannel.Flags & NL_FLAG_UTF8_NETBIOS_COMPUTER_NAME) {
 158                         workstation = bind_schannel.utf8_netbios_computer.u;
 159                 } else {
 160                         DEBUG(3, ("Request for schannel to without netbios workstation\n"));
 161                         return NT_STATUS_LOGON_FAILURE;
 162                 }
 163
 164                 status = schannel_get_creds_state(out_mem_ctx,
 165                                                   gensec_security->settings->lp_ctx,
 166                                                   workstation, &creds);
 167                 if (!NT_STATUS_IS_OK(status)) {
 168                         DEBUG(3, ("Could not find session key for attempted schannel connection from %s: %s\n",
 169                                   workstation, nt_errstr(status)));
 170                         if (NT_STATUS_EQUAL(status, NT_STATUS_INVALID_HANDLE)) {
 171                                 return NT_STATUS_LOGON_FAILURE;
 172                         }
 173                         return status;
 174                 }
 175
 176                 state->creds = talloc_steal(state, creds);
 177
 178                 bind_schannel_ack.MessageType = NL_NEGOTIATE_RESPONSE;
 179                 bind_schannel_ack.Flags = 0;
 180                 bind_schannel_ack.Buffer.dummy = 0x6c0000; /* actually I think
 181                                                             * this does not have
 182                                                             * any meaning here
 183                                                             * - gd */
 184
 185                 ndr_err = ndr_push_struct_blob(out, out_mem_ctx, &bind_schannel_ack,
 186                                                (ndr_push_flags_fn_t)ndr_push_NL_AUTH_MESSAGE);
 187                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 188                         status = ndr_map_error2ntstatus(ndr_err);
 189                         DEBUG(3, ("Could not return schannel bind ack for client %s: %s\n",
 190                                   workstation, nt_errstr(status)));
 191                         return status;
 192                 }
 193
 194                 state->state = SCHANNEL_STATE_UPDATE_1;
 195
 196                 return NT_STATUS_OK;
 197         }
 198         return NT_STATUS_INVALID_PARAMETER;
 199 }
 200
 201 /**
 202  * Return the struct netlogon_creds_CredentialState.
 203  *
 204  * Make sure not to call this unless gensec is using schannel...
 205  */
 206
 207 /* TODO: make this non-public */
 208
 209 _PUBLIC_ NTSTATUS dcerpc_schannel_creds(struct gensec_security *gensec_security,
 210                                         TALLOC_CTX *mem_ctx,
 211                                         struct netlogon_creds_CredentialState **creds)
 212 {
 213         struct schannel_state *state = talloc_get_type(gensec_security->private_data, struct schannel_state);
 214
 215         *creds = talloc_reference(mem_ctx, state->creds);
 216         if (!*creds) {
 217                 return NT_STATUS_NO_MEMORY;
 218         }
 219         return NT_STATUS_OK;
 220 }
 221
 222
 223 /**
 224  * Returns anonymous credentials for schannel, matching Win2k3.
 225  *
 226  */
 227
 228 static NTSTATUS schannel_session_info(struct gensec_security *gensec_security,
 229                                       TALLOC_CTX *mem_ctx,
 230                                       struct auth_session_info **_session_info)
 231 {
 232         return auth_anonymous_session_info(mem_ctx, gensec_security->settings->lp_ctx, _session_info);
 233 }
 234
 235 static NTSTATUS schannel_start(struct gensec_security *gensec_security)
 236 {
 237         struct schannel_state *state;
 238
 239         state = talloc(gensec_security, struct schannel_state);
 240         if (!state) {
 241                 return NT_STATUS_NO_MEMORY;
 242         }
 243
 244         state->state = SCHANNEL_STATE_START;
 245         state->seq_num = 0;
 246         gensec_security->private_data = state;
 247
 248         return NT_STATUS_OK;
 249 }
 250
 251 static NTSTATUS schannel_server_start(struct gensec_security *gensec_security)
 252 {
 253         NTSTATUS status;
 254         struct schannel_state *state;
 255
 256         status = schannel_start(gensec_security);
 257         if (!NT_STATUS_IS_OK(status)) {
 258                 return status;
 259         }
 260
 261         state = (struct schannel_state *)gensec_security->private_data;
 262         state->initiator = false;
 263
 264         return NT_STATUS_OK;
 265 }
 266
 267 static NTSTATUS schannel_client_start(struct gensec_security *gensec_security)
 268 {
 269         NTSTATUS status;
 270         struct schannel_state *state;
 271
 272         status = schannel_start(gensec_security);
 273         if (!NT_STATUS_IS_OK(status)) {
 274                 return status;
 275         }
 276
 277         state = (struct schannel_state *)gensec_security->private_data;
 278         state->initiator = true;
 279
 280         return NT_STATUS_OK;
 281 }
 282
 283
 284 static bool schannel_have_feature(struct gensec_security *gensec_security,
 285                                          uint32_t feature)
 286 {
 287         if (feature & (GENSEC_FEATURE_SIGN |
 288                        GENSEC_FEATURE_SEAL)) {
 289                 return true;
 290         }
 291         if (feature & GENSEC_FEATURE_DCE_STYLE) {
 292                 return true;
 293         }
 294         if (feature & GENSEC_FEATURE_ASYNC_REPLIES) {
 295                 return true;
 296         }
 297         return false;
 298 }
 299
 300 /*
 301   unseal a packet
 302 */
 303 static NTSTATUS schannel_unseal_packet(struct gensec_security *gensec_security,
 304                                        uint8_t *data, size_t length,
 305                                        const uint8_t *whole_pdu, size_t pdu_length,
 306                                        const DATA_BLOB *sig)
 307 {
 308         struct schannel_state *state =
 309                 talloc_get_type(gensec_security->private_data,
 310                                 struct schannel_state);
 311
 312         return netsec_incoming_packet(state, true,
 313                                       discard_const_p(uint8_t, data),
 314                                       length, sig);
 315 }
 316
 317 /*
 318   check the signature on a packet
 319 */
 320 static NTSTATUS schannel_check_packet(struct gensec_security *gensec_security,
 321                                       const uint8_t *data, size_t length,
 322                                       const uint8_t *whole_pdu, size_t pdu_length,
 323                                       const DATA_BLOB *sig)
 324 {
 325         struct schannel_state *state =
 326                 talloc_get_type(gensec_security->private_data,
 327                                 struct schannel_state);
 328
 329         return netsec_incoming_packet(state, false,
 330                                       discard_const_p(uint8_t, data),
 331                                       length, sig);
 332 }
 333 /*
 334   seal a packet
 335 */
 336 static NTSTATUS schannel_seal_packet(struct gensec_security *gensec_security,
 337                                      TALLOC_CTX *mem_ctx,
 338                                      uint8_t *data, size_t length,
 339                                      const uint8_t *whole_pdu, size_t pdu_length,
 340                                      DATA_BLOB *sig)
 341 {
 342         struct schannel_state *state =
 343                 talloc_get_type(gensec_security->private_data,
 344                                 struct schannel_state);
 345
 346         return netsec_outgoing_packet(state, mem_ctx, true,
 347                                       data, length, sig);
 348 }
 349
 350 /*
 351   sign a packet
 352 */
 353 static NTSTATUS schannel_sign_packet(struct gensec_security *gensec_security,
 354                                      TALLOC_CTX *mem_ctx,
 355                                      const uint8_t *data, size_t length,
 356                                      const uint8_t *whole_pdu, size_t pdu_length,
 357                                      DATA_BLOB *sig)
 358 {
 359         struct schannel_state *state =
 360                 talloc_get_type(gensec_security->private_data,
 361                                 struct schannel_state);
 362
 363         return netsec_outgoing_packet(state, mem_ctx, false,
 364                                       discard_const_p(uint8_t, data),
 365                                       length, sig);
 366 }
 367
 368 static const struct gensec_security_ops gensec_schannel_security_ops = {
 369         .name           = "schannel",
 370         .auth_type      = DCERPC_AUTH_TYPE_SCHANNEL,
 371         .client_start   = schannel_client_start,
 372         .server_start   = schannel_server_start,
 373         .update         = schannel_update,
 374         .seal_packet    = schannel_seal_packet,
 375         .sign_packet    = schannel_sign_packet,
 376         .check_packet   = schannel_check_packet,
 377         .unseal_packet  = schannel_unseal_packet,
 378         .session_key    = schannel_session_key,
 379         .session_info   = schannel_session_info,
 380         .sig_size       = schannel_sig_size,
 381         .have_feature   = schannel_have_feature,
 382         .enabled        = true,
 383         .priority       = GENSEC_SCHANNEL
 384 };
 385
 386 _PUBLIC_ NTSTATUS gensec_schannel_init(void)
 387 {
 388         NTSTATUS ret;
 389         ret = gensec_register(&gensec_schannel_security_ops);
 390         if (!NT_STATUS_IS_OK(ret)) {
 391                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
 392                         gensec_schannel_security_ops.name));
 393                 return ret;
 394         }
 395
 396         return ret;
 397 }