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