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