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