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 = talloc_reference(state, cli_credentials_get_netlogon_creds(gensec_security->credentials));
  77
  78                 bind_schannel.MessageType = NL_NEGOTIATE_REQUEST;
  79 #if 0
  80                 /* to support this we'd need to have access to the full domain name */
  81                 /* 0x17, 23 */
  82                 bind_schannel.Flags = NL_FLAG_OEM_NETBIOS_DOMAIN_NAME |
  83                                       NL_FLAG_OEM_NETBIOS_COMPUTER_NAME |
  84                                       NL_FLAG_UTF8_DNS_DOMAIN_NAME |
  85                                       NL_FLAG_UTF8_NETBIOS_COMPUTER_NAME;
  86                 bind_schannel.oem_netbios_domain.a = cli_credentials_get_domain(gensec_security->credentials);
  87                 bind_schannel.oem_netbios_computer.a = cli_credentials_get_workstation(gensec_security->credentials);
  88                 bind_schannel.utf8_dns_domain = cli_credentials_get_realm(gensec_security->credentials);
  89                 /* w2k3 refuses us if we use the full DNS workstation?
  90                  why? perhaps because we don't fill in the dNSHostName
  91                  attribute in the machine account? */
  92                 bind_schannel.utf8_netbios_computer = cli_credentials_get_workstation(gensec_security->credentials);
  93 #else
  94                 bind_schannel.Flags = NL_FLAG_OEM_NETBIOS_DOMAIN_NAME |
  95                                       NL_FLAG_OEM_NETBIOS_COMPUTER_NAME;
  96                 bind_schannel.oem_netbios_domain.a = cli_credentials_get_domain(gensec_security->credentials);
  97                 bind_schannel.oem_netbios_computer.a = cli_credentials_get_workstation(gensec_security->credentials);
  98 #endif
  99
 100                 ndr_err = ndr_push_struct_blob(out, out_mem_ctx, &bind_schannel,
 101                                                (ndr_push_flags_fn_t)ndr_push_NL_AUTH_MESSAGE);
 102                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 103                         status = ndr_map_error2ntstatus(ndr_err);
 104                         DEBUG(3, ("Could not create schannel bind: %s\n",
 105                                   nt_errstr(status)));
 106                         return status;
 107                 }
 108
 109                 state->state = SCHANNEL_STATE_UPDATE_1;
 110
 111                 return NT_STATUS_MORE_PROCESSING_REQUIRED;
 112         case GENSEC_SERVER:
 113
 114                 if (state->state != SCHANNEL_STATE_START) {
 115                         /* no third leg on this protocol */
 116                         return NT_STATUS_INVALID_PARAMETER;
 117                 }
 118
 119                 /* parse the schannel startup blob */
 120                 ndr_err = ndr_pull_struct_blob(&in, out_mem_ctx, &bind_schannel,
 121                         (ndr_pull_flags_fn_t)ndr_pull_NL_AUTH_MESSAGE);
 122                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 123                         status = ndr_map_error2ntstatus(ndr_err);
 124                         DEBUG(3, ("Could not parse incoming schannel bind: %s\n",
 125                                   nt_errstr(status)));
 126                         return status;
 127                 }
 128
 129                 if (bind_schannel.Flags & NL_FLAG_OEM_NETBIOS_DOMAIN_NAME) {
 130                         domain = bind_schannel.oem_netbios_domain.a;
 131                         if (strcasecmp_m(domain, lpcfg_workgroup(gensec_security->settings->lp_ctx)) != 0) {
 132                                 DEBUG(3, ("Request for schannel to incorrect domain: %s != our domain %s\n",
 133                                           domain, lpcfg_workgroup(gensec_security->settings->lp_ctx)));
 134                                 return NT_STATUS_LOGON_FAILURE;
 135                         }
 136                 } else if (bind_schannel.Flags & NL_FLAG_UTF8_DNS_DOMAIN_NAME) {
 137                         domain = bind_schannel.utf8_dns_domain.u;
 138                         if (strcasecmp_m(domain, lpcfg_dnsdomain(gensec_security->settings->lp_ctx)) != 0) {
 139                                 DEBUG(3, ("Request for schannel to incorrect domain: %s != our domain %s\n",
 140                                           domain, lpcfg_dnsdomain(gensec_security->settings->lp_ctx)));
 141                                 return NT_STATUS_LOGON_FAILURE;
 142                         }
 143                 } else {
 144                         DEBUG(3, ("Request for schannel to without domain\n"));
 145                         return NT_STATUS_LOGON_FAILURE;
 146                 }
 147
 148                 if (bind_schannel.Flags & NL_FLAG_OEM_NETBIOS_COMPUTER_NAME) {
 149                         workstation = bind_schannel.oem_netbios_computer.a;
 150                 } else if (bind_schannel.Flags & NL_FLAG_UTF8_NETBIOS_COMPUTER_NAME) {
 151                         workstation = bind_schannel.utf8_netbios_computer.u;
 152                 } else {
 153                         DEBUG(3, ("Request for schannel to without netbios workstation\n"));
 154                         return NT_STATUS_LOGON_FAILURE;
 155                 }
 156
 157                 status = schannel_get_creds_state(out_mem_ctx,
 158                                                   gensec_security->settings->lp_ctx,
 159                                                   workstation, &creds);
 160                 if (!NT_STATUS_IS_OK(status)) {
 161                         DEBUG(3, ("Could not find session key for attempted schannel connection from %s: %s\n",
 162                                   workstation, nt_errstr(status)));
 163                         if (NT_STATUS_EQUAL(status, NT_STATUS_INVALID_HANDLE)) {
 164                                 return NT_STATUS_LOGON_FAILURE;
 165                         }
 166                         return status;
 167                 }
 168
 169                 state->creds = talloc_steal(state, creds);
 170
 171                 bind_schannel_ack.MessageType = NL_NEGOTIATE_RESPONSE;
 172                 bind_schannel_ack.Flags = 0;
 173                 bind_schannel_ack.Buffer.dummy = 0x6c0000; /* actually I think
 174                                                             * this does not have
 175                                                             * any meaning here
 176                                                             * - gd */
 177
 178                 ndr_err = ndr_push_struct_blob(out, out_mem_ctx, &bind_schannel_ack,
 179                                                (ndr_push_flags_fn_t)ndr_push_NL_AUTH_MESSAGE);
 180                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 181                         status = ndr_map_error2ntstatus(ndr_err);
 182                         DEBUG(3, ("Could not return schannel bind ack for client %s: %s\n",
 183                                   workstation, nt_errstr(status)));
 184                         return status;
 185                 }
 186
 187                 state->state = SCHANNEL_STATE_UPDATE_1;
 188
 189                 return NT_STATUS_OK;
 190         }
 191         return NT_STATUS_INVALID_PARAMETER;
 192 }
 193
 194 /**
 195  * Return the struct netlogon_creds_CredentialState.
 196  *
 197  * Make sure not to call this unless gensec is using schannel...
 198  */
 199
 200 /* TODO: make this non-public */
 201
 202 _PUBLIC_ NTSTATUS dcerpc_schannel_creds(struct gensec_security *gensec_security,
 203                                         TALLOC_CTX *mem_ctx,
 204                                         struct netlogon_creds_CredentialState **creds)
 205 {
 206         struct schannel_state *state = talloc_get_type(gensec_security->private_data, struct schannel_state);
 207
 208         *creds = talloc_reference(mem_ctx, state->creds);
 209         if (!*creds) {
 210                 return NT_STATUS_NO_MEMORY;
 211         }
 212         return NT_STATUS_OK;
 213 }
 214
 215
 216 /**
 217  * Returns anonymous credentials for schannel, matching Win2k3.
 218  *
 219  */
 220
 221 static NTSTATUS schannel_session_info(struct gensec_security *gensec_security,
 222                                       TALLOC_CTX *mem_ctx,
 223                                       struct auth_session_info **_session_info)
 224 {
 225         return auth_anonymous_session_info(mem_ctx, gensec_security->settings->lp_ctx, _session_info);
 226 }
 227
 228 static NTSTATUS schannel_start(struct gensec_security *gensec_security)
 229 {
 230         struct schannel_state *state;
 231
 232         state = talloc(gensec_security, struct schannel_state);
 233         if (!state) {
 234                 return NT_STATUS_NO_MEMORY;
 235         }
 236
 237         state->state = SCHANNEL_STATE_START;
 238         state->seq_num = 0;
 239         gensec_security->private_data = state;
 240
 241         return NT_STATUS_OK;
 242 }
 243
 244 static NTSTATUS schannel_server_start(struct gensec_security *gensec_security)
 245 {
 246         NTSTATUS status;
 247         struct schannel_state *state;
 248
 249         status = schannel_start(gensec_security);
 250         if (!NT_STATUS_IS_OK(status)) {
 251                 return status;
 252         }
 253
 254         state = (struct schannel_state *)gensec_security->private_data;
 255         state->initiator = false;
 256
 257         return NT_STATUS_OK;
 258 }
 259
 260 static NTSTATUS schannel_client_start(struct gensec_security *gensec_security)
 261 {
 262         NTSTATUS status;
 263         struct schannel_state *state;
 264
 265         status = schannel_start(gensec_security);
 266         if (!NT_STATUS_IS_OK(status)) {
 267                 return status;
 268         }
 269
 270         state = (struct schannel_state *)gensec_security->private_data;
 271         state->initiator = true;
 272
 273         return NT_STATUS_OK;
 274 }
 275
 276
 277 static bool schannel_have_feature(struct gensec_security *gensec_security,
 278                                          uint32_t feature)
 279 {
 280         if (feature & (GENSEC_FEATURE_SIGN |
 281                        GENSEC_FEATURE_SEAL)) {
 282                 return true;
 283         }
 284         if (feature & GENSEC_FEATURE_DCE_STYLE) {
 285                 return true;
 286         }
 287         if (feature & GENSEC_FEATURE_ASYNC_REPLIES) {
 288                 return true;
 289         }
 290         return false;
 291 }
 292
 293 /*
 294   unseal a packet
 295 */
 296 static NTSTATUS schannel_unseal_packet(struct gensec_security *gensec_security,
 297                                        uint8_t *data, size_t length,
 298                                        const uint8_t *whole_pdu, size_t pdu_length,
 299                                        const DATA_BLOB *sig)
 300 {
 301         struct schannel_state *state =
 302                 talloc_get_type(gensec_security->private_data,
 303                                 struct schannel_state);
 304
 305         return netsec_incoming_packet(state, true,
 306                                       discard_const_p(uint8_t, data),
 307                                       length, sig);
 308 }
 309
 310 /*
 311   check the signature on a packet
 312 */
 313 static NTSTATUS schannel_check_packet(struct gensec_security *gensec_security,
 314                                       const uint8_t *data, size_t length,
 315                                       const uint8_t *whole_pdu, size_t pdu_length,
 316                                       const DATA_BLOB *sig)
 317 {
 318         struct schannel_state *state =
 319                 talloc_get_type(gensec_security->private_data,
 320                                 struct schannel_state);
 321
 322         return netsec_incoming_packet(state, false,
 323                                       discard_const_p(uint8_t, data),
 324                                       length, sig);
 325 }
 326 /*
 327   seal a packet
 328 */
 329 static NTSTATUS schannel_seal_packet(struct gensec_security *gensec_security,
 330                                      TALLOC_CTX *mem_ctx,
 331                                      uint8_t *data, size_t length,
 332                                      const uint8_t *whole_pdu, size_t pdu_length,
 333                                      DATA_BLOB *sig)
 334 {
 335         struct schannel_state *state =
 336                 talloc_get_type(gensec_security->private_data,
 337                                 struct schannel_state);
 338
 339         return netsec_outgoing_packet(state, mem_ctx, true,
 340                                       data, length, sig);
 341 }
 342
 343 /*
 344   sign a packet
 345 */
 346 static NTSTATUS schannel_sign_packet(struct gensec_security *gensec_security,
 347                                      TALLOC_CTX *mem_ctx,
 348                                      const uint8_t *data, size_t length,
 349                                      const uint8_t *whole_pdu, size_t pdu_length,
 350                                      DATA_BLOB *sig)
 351 {
 352         struct schannel_state *state =
 353                 talloc_get_type(gensec_security->private_data,
 354                                 struct schannel_state);
 355
 356         return netsec_outgoing_packet(state, mem_ctx, false,
 357                                       discard_const_p(uint8_t, data),
 358                                       length, sig);
 359 }
 360
 361 static const struct gensec_security_ops gensec_schannel_security_ops = {
 362         .name           = "schannel",
 363         .auth_type      = DCERPC_AUTH_TYPE_SCHANNEL,
 364         .client_start   = schannel_client_start,
 365         .server_start   = schannel_server_start,
 366         .update         = schannel_update,
 367         .seal_packet    = schannel_seal_packet,
 368         .sign_packet    = schannel_sign_packet,
 369         .check_packet   = schannel_check_packet,
 370         .unseal_packet  = schannel_unseal_packet,
 371         .session_key    = schannel_session_key,
 372         .session_info   = schannel_session_info,
 373         .sig_size       = schannel_sig_size,
 374         .have_feature   = schannel_have_feature,
 375         .enabled        = true,
 376         .priority       = GENSEC_SCHANNEL
 377 };
 378
 379 _PUBLIC_ NTSTATUS gensec_schannel_init(void)
 380 {
 381         NTSTATUS ret;
 382         ret = gensec_register(&gensec_schannel_security_ops);
 383         if (!NT_STATUS_IS_OK(ret)) {
 384                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
 385                         gensec_schannel_security_ops.name));
 386                 return ret;
 387         }
 388
 389         return ret;
 390 }