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                                        const DATA_BLOB in, DATA_BLOB *out)
  56 {
  57         struct schannel_state *state = (struct schannel_state *)gensec_security->private_data;
  58         NTSTATUS status;
  59         enum ndr_err_code ndr_err;
  60         struct NL_AUTH_MESSAGE bind_schannel;
  61         struct NL_AUTH_MESSAGE bind_schannel_ack;
  62         struct netlogon_creds_CredentialState *creds;
  63         const char *workstation;
  64         const char *domain;
  65
  66         *out = data_blob(NULL, 0);
  67
  68         switch (gensec_security->gensec_role) {
  69         case GENSEC_CLIENT:
  70                 if (state->state != SCHANNEL_STATE_START) {
  71                         /* we could parse the bind ack, but we don't know what it is yet */
  72                         return NT_STATUS_OK;
  73                 }
  74
  75                 state->creds = talloc_reference(state, cli_credentials_get_netlogon_creds(gensec_security->credentials));
  76
  77                 bind_schannel.MessageType = NL_NEGOTIATE_REQUEST;
  78 #if 0
  79                 /* to support this we'd need to have access to the full domain name */
  80                 /* 0x17, 23 */
  81                 bind_schannel.Flags = NL_FLAG_OEM_NETBIOS_DOMAIN_NAME |
  82                                       NL_FLAG_OEM_NETBIOS_COMPUTER_NAME |
  83                                       NL_FLAG_UTF8_DNS_DOMAIN_NAME |
  84                                       NL_FLAG_UTF8_NETBIOS_COMPUTER_NAME;
  85                 bind_schannel.oem_netbios_domain.a = cli_credentials_get_domain(gensec_security->credentials);
  86                 bind_schannel.oem_netbios_computer.a = cli_credentials_get_workstation(gensec_security->credentials);
  87                 bind_schannel.utf8_dns_domain = cli_credentials_get_realm(gensec_security->credentials);
  88                 /* w2k3 refuses us if we use the full DNS workstation?
  89                  why? perhaps because we don't fill in the dNSHostName
  90                  attribute in the machine account? */
  91                 bind_schannel.utf8_netbios_computer = cli_credentials_get_workstation(gensec_security->credentials);
  92 #else
  93                 bind_schannel.Flags = NL_FLAG_OEM_NETBIOS_DOMAIN_NAME |
  94                                       NL_FLAG_OEM_NETBIOS_COMPUTER_NAME;
  95                 bind_schannel.oem_netbios_domain.a = cli_credentials_get_domain(gensec_security->credentials);
  96                 bind_schannel.oem_netbios_computer.a = cli_credentials_get_workstation(gensec_security->credentials);
  97 #endif
  98
  99                 ndr_err = ndr_push_struct_blob(out, out_mem_ctx, &bind_schannel,
 100                                                (ndr_push_flags_fn_t)ndr_push_NL_AUTH_MESSAGE);
 101                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 102                         status = ndr_map_error2ntstatus(ndr_err);
 103                         DEBUG(3, ("Could not create schannel bind: %s\n",
 104                                   nt_errstr(status)));
 105                         return status;
 106                 }
 107
 108                 state->state = SCHANNEL_STATE_UPDATE_1;
 109
 110                 return NT_STATUS_MORE_PROCESSING_REQUIRED;
 111         case GENSEC_SERVER:
 112
 113                 if (state->state != SCHANNEL_STATE_START) {
 114                         /* no third leg on this protocol */
 115                         return NT_STATUS_INVALID_PARAMETER;
 116                 }
 117
 118                 /* parse the schannel startup blob */
 119                 ndr_err = ndr_pull_struct_blob(&in, out_mem_ctx, &bind_schannel,
 120                         (ndr_pull_flags_fn_t)ndr_pull_NL_AUTH_MESSAGE);
 121                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 122                         status = ndr_map_error2ntstatus(ndr_err);
 123                         DEBUG(3, ("Could not parse incoming schannel bind: %s\n",
 124                                   nt_errstr(status)));
 125                         return status;
 126                 }
 127
 128                 if (bind_schannel.Flags & NL_FLAG_OEM_NETBIOS_DOMAIN_NAME) {
 129                         domain = bind_schannel.oem_netbios_domain.a;
 130                         if (strcasecmp_m(domain, lpcfg_workgroup(gensec_security->settings->lp_ctx)) != 0) {
 131                                 DEBUG(3, ("Request for schannel to incorrect domain: %s != our domain %s\n",
 132                                           domain, lpcfg_workgroup(gensec_security->settings->lp_ctx)));
 133                                 return NT_STATUS_LOGON_FAILURE;
 134                         }
 135                 } else if (bind_schannel.Flags & NL_FLAG_UTF8_DNS_DOMAIN_NAME) {
 136                         domain = bind_schannel.utf8_dns_domain.u;
 137                         if (strcasecmp_m(domain, lpcfg_dnsdomain(gensec_security->settings->lp_ctx)) != 0) {
 138                                 DEBUG(3, ("Request for schannel to incorrect domain: %s != our domain %s\n",
 139                                           domain, lpcfg_dnsdomain(gensec_security->settings->lp_ctx)));
 140                                 return NT_STATUS_LOGON_FAILURE;
 141                         }
 142                 } else {
 143                         DEBUG(3, ("Request for schannel to without domain\n"));
 144                         return NT_STATUS_LOGON_FAILURE;
 145                 }
 146
 147                 if (bind_schannel.Flags & NL_FLAG_OEM_NETBIOS_COMPUTER_NAME) {
 148                         workstation = bind_schannel.oem_netbios_computer.a;
 149                 } else if (bind_schannel.Flags & NL_FLAG_UTF8_NETBIOS_COMPUTER_NAME) {
 150                         workstation = bind_schannel.utf8_netbios_computer.u;
 151                 } else {
 152                         DEBUG(3, ("Request for schannel to without netbios workstation\n"));
 153                         return NT_STATUS_LOGON_FAILURE;
 154                 }
 155
 156                 status = schannel_get_creds_state(out_mem_ctx,
 157                                                   gensec_security->settings->lp_ctx,
 158                                                   workstation, &creds);
 159                 if (!NT_STATUS_IS_OK(status)) {
 160                         DEBUG(3, ("Could not find session key for attempted schannel connection from %s: %s\n",
 161                                   workstation, nt_errstr(status)));
 162                         if (NT_STATUS_EQUAL(status, NT_STATUS_INVALID_HANDLE)) {
 163                                 return NT_STATUS_LOGON_FAILURE;
 164                         }
 165                         return status;
 166                 }
 167
 168                 state->creds = talloc_steal(state, creds);
 169
 170                 bind_schannel_ack.MessageType = NL_NEGOTIATE_RESPONSE;
 171                 bind_schannel_ack.Flags = 0;
 172                 bind_schannel_ack.Buffer.dummy = 0x6c0000; /* actually I think
 173                                                             * this does not have
 174                                                             * any meaning here
 175                                                             * - gd */
 176
 177                 ndr_err = ndr_push_struct_blob(out, out_mem_ctx, &bind_schannel_ack,
 178                                                (ndr_push_flags_fn_t)ndr_push_NL_AUTH_MESSAGE);
 179                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 180                         status = ndr_map_error2ntstatus(ndr_err);
 181                         DEBUG(3, ("Could not return schannel bind ack for client %s: %s\n",
 182                                   workstation, nt_errstr(status)));
 183                         return status;
 184                 }
 185
 186                 state->state = SCHANNEL_STATE_UPDATE_1;
 187
 188                 return NT_STATUS_OK;
 189         }
 190         return NT_STATUS_INVALID_PARAMETER;
 191 }
 192
 193 /**
 194  * Return the struct netlogon_creds_CredentialState.
 195  *
 196  * Make sure not to call this unless gensec is using schannel...
 197  */
 198
 199 /* TODO: make this non-public */
 200
 201 _PUBLIC_ NTSTATUS dcerpc_schannel_creds(struct gensec_security *gensec_security,
 202                                         TALLOC_CTX *mem_ctx,
 203                                         struct netlogon_creds_CredentialState **creds)
 204 {
 205         struct schannel_state *state = talloc_get_type(gensec_security->private_data, struct schannel_state);
 206
 207         *creds = talloc_reference(mem_ctx, state->creds);
 208         if (!*creds) {
 209                 return NT_STATUS_NO_MEMORY;
 210         }
 211         return NT_STATUS_OK;
 212 }
 213
 214
 215 /**
 216  * Returns anonymous credentials for schannel, matching Win2k3.
 217  *
 218  */
 219
 220 static NTSTATUS schannel_session_info(struct gensec_security *gensec_security,
 221                                       TALLOC_CTX *mem_ctx,
 222                                       struct auth_session_info **_session_info)
 223 {
 224         return auth_anonymous_session_info(mem_ctx, gensec_security->settings->lp_ctx, _session_info);
 225 }
 226
 227 static NTSTATUS schannel_start(struct gensec_security *gensec_security)
 228 {
 229         struct schannel_state *state;
 230
 231         state = talloc(gensec_security, struct schannel_state);
 232         if (!state) {
 233                 return NT_STATUS_NO_MEMORY;
 234         }
 235
 236         state->state = SCHANNEL_STATE_START;
 237         state->seq_num = 0;
 238         gensec_security->private_data = state;
 239
 240         return NT_STATUS_OK;
 241 }
 242
 243 static NTSTATUS schannel_server_start(struct gensec_security *gensec_security)
 244 {
 245         NTSTATUS status;
 246         struct schannel_state *state;
 247
 248         status = schannel_start(gensec_security);
 249         if (!NT_STATUS_IS_OK(status)) {
 250                 return status;
 251         }
 252
 253         state = (struct schannel_state *)gensec_security->private_data;
 254         state->initiator = false;
 255
 256         return NT_STATUS_OK;
 257 }
 258
 259 static NTSTATUS schannel_client_start(struct gensec_security *gensec_security)
 260 {
 261         NTSTATUS status;
 262         struct schannel_state *state;
 263
 264         status = schannel_start(gensec_security);
 265         if (!NT_STATUS_IS_OK(status)) {
 266                 return status;
 267         }
 268
 269         state = (struct schannel_state *)gensec_security->private_data;
 270         state->initiator = true;
 271
 272         return NT_STATUS_OK;
 273 }
 274
 275
 276 static bool schannel_have_feature(struct gensec_security *gensec_security,
 277                                          uint32_t feature)
 278 {
 279         if (feature & (GENSEC_FEATURE_SIGN |
 280                        GENSEC_FEATURE_SEAL)) {
 281                 return true;
 282         }
 283         if (feature & GENSEC_FEATURE_DCE_STYLE) {
 284                 return true;
 285         }
 286         if (feature & GENSEC_FEATURE_ASYNC_REPLIES) {
 287                 return true;
 288         }
 289         return false;
 290 }
 291
 292 /*
 293   unseal a packet
 294 */
 295 static NTSTATUS schannel_unseal_packet(struct gensec_security *gensec_security,
 296                                        uint8_t *data, size_t length,
 297                                        const uint8_t *whole_pdu, size_t pdu_length,
 298                                        const DATA_BLOB *sig)
 299 {
 300         struct schannel_state *state =
 301                 talloc_get_type(gensec_security->private_data,
 302                                 struct schannel_state);
 303
 304         return netsec_incoming_packet(state, true,
 305                                       discard_const_p(uint8_t, data),
 306                                       length, sig);
 307 }
 308
 309 /*
 310   check the signature on a packet
 311 */
 312 static NTSTATUS schannel_check_packet(struct gensec_security *gensec_security,
 313                                       const uint8_t *data, size_t length,
 314                                       const uint8_t *whole_pdu, size_t pdu_length,
 315                                       const DATA_BLOB *sig)
 316 {
 317         struct schannel_state *state =
 318                 talloc_get_type(gensec_security->private_data,
 319                                 struct schannel_state);
 320
 321         return netsec_incoming_packet(state, false,
 322                                       discard_const_p(uint8_t, data),
 323                                       length, sig);
 324 }
 325 /*
 326   seal a packet
 327 */
 328 static NTSTATUS schannel_seal_packet(struct gensec_security *gensec_security,
 329                                      TALLOC_CTX *mem_ctx,
 330                                      uint8_t *data, size_t length,
 331                                      const uint8_t *whole_pdu, size_t pdu_length,
 332                                      DATA_BLOB *sig)
 333 {
 334         struct schannel_state *state =
 335                 talloc_get_type(gensec_security->private_data,
 336                                 struct schannel_state);
 337
 338         return netsec_outgoing_packet(state, mem_ctx, true,
 339                                       data, length, sig);
 340 }
 341
 342 /*
 343   sign a packet
 344 */
 345 static NTSTATUS schannel_sign_packet(struct gensec_security *gensec_security,
 346                                      TALLOC_CTX *mem_ctx,
 347                                      const uint8_t *data, size_t length,
 348                                      const uint8_t *whole_pdu, size_t pdu_length,
 349                                      DATA_BLOB *sig)
 350 {
 351         struct schannel_state *state =
 352                 talloc_get_type(gensec_security->private_data,
 353                                 struct schannel_state);
 354
 355         return netsec_outgoing_packet(state, mem_ctx, false,
 356                                       discard_const_p(uint8_t, data),
 357                                       length, sig);
 358 }
 359
 360 static const struct gensec_security_ops gensec_schannel_security_ops = {
 361         .name           = "schannel",
 362         .auth_type      = DCERPC_AUTH_TYPE_SCHANNEL,
 363         .client_start   = schannel_client_start,
 364         .server_start   = schannel_server_start,
 365         .update         = schannel_update,
 366         .seal_packet    = schannel_seal_packet,
 367         .sign_packet    = schannel_sign_packet,
 368         .check_packet   = schannel_check_packet,
 369         .unseal_packet  = schannel_unseal_packet,
 370         .session_key    = schannel_session_key,
 371         .session_info   = schannel_session_info,
 372         .sig_size       = schannel_sig_size,
 373         .have_feature   = schannel_have_feature,
 374         .enabled        = true,
 375         .priority       = GENSEC_SCHANNEL
 376 };
 377
 378 _PUBLIC_ NTSTATUS gensec_schannel_init(void)
 379 {
 380         NTSTATUS ret;
 381         ret = gensec_register(&gensec_schannel_security_ops);
 382         if (!NT_STATUS_IS_OK(ret)) {
 383                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
 384                         gensec_schannel_security_ops.name));
 385                 return ret;
 386         }
 387
 388         return ret;
 389 }