source4/kdc/pac-glue.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    PAC Glue between Samba and the KDC
   5
   6    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2005-2009
   7    Copyright (C) Simo Sorce <idra@samba.org> 2010
   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
  20    You should have received a copy of the GNU General Public License
  21    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  22 */
  23
  24 #include "includes.h"
  25 #include "../libds/common/flags.h"
  26 #include <ldb.h>
  27 #include "auth/auth.h"
  28 #include "auth/auth_sam_reply.h"
  29 #include "kdc/kdc-glue.h"
  30 #include "kdc/pac-glue.h"
  31 #include "param/param.h"
  32 #include "librpc/gen_ndr/ndr_krb5pac.h"
  33
  34 static
  35 NTSTATUS samba_get_logon_info_pac_blob(TALLOC_CTX *mem_ctx,
  36                                        struct auth_user_info_dc *info,
  37                                        DATA_BLOB *pac_data)
  38 {
  39         struct netr_SamInfo3 *info3;
  40         union PAC_INFO pac_info;
  41         enum ndr_err_code ndr_err;
  42         NTSTATUS nt_status;
  43
  44         ZERO_STRUCT(pac_info);
  45
  46         nt_status = auth_convert_user_info_dc_saminfo3(mem_ctx, info, &info3);
  47         if (!NT_STATUS_IS_OK(nt_status)) {
  48                 DEBUG(1, ("Getting Samba info failed: %s\n",
  49                           nt_errstr(nt_status)));
  50                 return nt_status;
  51         }
  52
  53         pac_info.logon_info.info = talloc_zero(mem_ctx, struct PAC_LOGON_INFO);
  54         if (!mem_ctx) {
  55                 return NT_STATUS_NO_MEMORY;
  56         }
  57
  58         pac_info.logon_info.info->info3 = *info3;
  59
  60         ndr_err = ndr_push_union_blob(pac_data, mem_ctx, &pac_info,
  61                                       PAC_TYPE_LOGON_INFO,
  62                                       (ndr_push_flags_fn_t)ndr_push_PAC_INFO);
  63         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
  64                 nt_status = ndr_map_error2ntstatus(ndr_err);
  65                 DEBUG(1, ("PAC (presig) push failed: %s\n",
  66                           nt_errstr(nt_status)));
  67                 return nt_status;
  68         }
  69
  70         return NT_STATUS_OK;
  71 }
  72
  73 krb5_error_code samba_make_krb5_pac(krb5_context context,
  74                                     DATA_BLOB *pac_blob,
  75                                     DATA_BLOB *deleg_blob,
  76                                     krb5_pac *pac)
  77 {
  78         krb5_data pac_data;
  79         krb5_data deleg_data;
  80         krb5_error_code ret;
  81
  82         /* The user account may be set not to want the PAC */
  83         if (!pac_blob) {
  84                 return 0;
  85         }
  86
  87         ret = krb5_data_copy(&pac_data, pac_blob->data, pac_blob->length);
  88         if (ret != 0) {
  89                 return ret;
  90         }
  91
  92         ZERO_STRUCT(deleg_data);
  93         if (deleg_blob) {
  94                 ret = krb5_data_copy(&deleg_data,
  95                                      deleg_blob->data,
  96                                      deleg_blob->length);
  97                 if (ret != 0) {
  98                         krb5_data_free(&pac_data);
  99                         return ret;
 100                 }
 101         }
 102
 103         ret = krb5_pac_init(context, pac);
 104         if (ret != 0) {
 105                 krb5_data_free(&pac_data);
 106                 krb5_data_free(&deleg_data);
 107                 return ret;
 108         }
 109
 110         ret = krb5_pac_add_buffer(context, *pac, PAC_TYPE_LOGON_INFO, &pac_data);
 111         krb5_data_free(&pac_data);
 112         if (ret != 0) {
 113                 krb5_data_free(&deleg_data);
 114                 return ret;
 115         }
 116
 117         if (deleg_blob) {
 118                 ret = krb5_pac_add_buffer(context, *pac,
 119                                           PAC_TYPE_CONSTRAINED_DELEGATION,
 120                                           &deleg_data);
 121                 krb5_data_free(&deleg_data);
 122                 if (ret != 0) {
 123                         return ret;
 124                 }
 125         }
 126
 127         return ret;
 128 }
 129
 130 bool samba_princ_needs_pac(struct hdb_entry_ex *princ)
 131 {
 132
 133         struct samba_kdc_entry *p = talloc_get_type(princ->ctx, struct samba_kdc_entry);
 134         uint32_t userAccountControl;
 135
 136
 137         /* The service account may be set not to want the PAC */
 138         userAccountControl = ldb_msg_find_attr_as_uint(p->msg, "userAccountControl", 0);
 139         if (userAccountControl & UF_NO_AUTH_DATA_REQUIRED) {
 140                 return false;
 141         }
 142
 143         return true;
 144 }
 145
 146 /* Was the krbtgt an RODC (and we are not) */
 147 bool samba_krbtgt_was_untrusted_rodc(struct hdb_entry_ex *princ)
 148 {
 149
 150         struct samba_kdc_entry *p = talloc_get_type(princ->ctx, struct samba_kdc_entry);
 151         int rodc_krbtgt_number;
 152
 153         /* Determine if this was printed by an RODC */
 154         rodc_krbtgt_number = ldb_msg_find_attr_as_int(p->msg, "msDS-SecondaryKrbTgtNumber", -1);
 155         if (rodc_krbtgt_number == -1) {
 156                 return false;
 157         } else if (rodc_krbtgt_number != p->kdc_db_ctx->my_krbtgt_number) {
 158                 return true;
 159         }
 160
 161         return false;
 162 }
 163
 164 NTSTATUS samba_kdc_get_pac_blob(TALLOC_CTX *mem_ctx,
 165                                 struct hdb_entry_ex *client,
 166                                 DATA_BLOB **_pac_blob)
 167 {
 168         struct samba_kdc_entry *p = talloc_get_type(client->ctx, struct samba_kdc_entry);
 169         struct auth_user_info_dc *user_info_dc;
 170         DATA_BLOB *pac_blob;
 171         NTSTATUS nt_status;
 172
 173         /* The user account may be set not to want the PAC */
 174         if ( ! samba_princ_needs_pac(client)) {
 175                 *_pac_blob = NULL;
 176                 return NT_STATUS_OK;
 177         }
 178
 179         pac_blob = talloc_zero(mem_ctx, DATA_BLOB);
 180         if (!pac_blob) {
 181                 return NT_STATUS_NO_MEMORY;
 182         }
 183
 184         nt_status = authsam_make_user_info_dc(mem_ctx, p->kdc_db_ctx->samdb,
 185                                              lpcfg_netbios_name(p->kdc_db_ctx->lp_ctx),
 186                                              lpcfg_sam_name(p->kdc_db_ctx->lp_ctx),
 187                                              p->realm_dn,
 188                                              p->msg,
 189                                              data_blob(NULL, 0),
 190                                              data_blob(NULL, 0),
 191                                              &user_info_dc);
 192         if (!NT_STATUS_IS_OK(nt_status)) {
 193                 DEBUG(0, ("Getting user info for PAC failed: %s\n",
 194                           nt_errstr(nt_status)));
 195                 return nt_status;
 196         }
 197
 198         nt_status = samba_get_logon_info_pac_blob(mem_ctx, user_info_dc, pac_blob);
 199         if (!NT_STATUS_IS_OK(nt_status)) {
 200                 DEBUG(0, ("Building PAC failed: %s\n",
 201                           nt_errstr(nt_status)));
 202                 return nt_status;
 203         }
 204
 205         *_pac_blob = pac_blob;
 206         return NT_STATUS_OK;
 207 }
 208
 209 NTSTATUS samba_kdc_update_pac_blob(TALLOC_CTX *mem_ctx,
 210                                    krb5_context context,
 211                                    const krb5_pac pac, DATA_BLOB *pac_blob)
 212 {
 213         struct auth_user_info_dc *user_info_dc;
 214         krb5_error_code ret;
 215         NTSTATUS nt_status;
 216
 217         ret = kerberos_pac_to_user_info_dc(mem_ctx, pac,
 218                                            context, &user_info_dc, NULL, NULL);
 219         if (ret) {
 220                 return NT_STATUS_UNSUCCESSFUL;
 221         }
 222
 223         nt_status = samba_get_logon_info_pac_blob(mem_ctx,
 224                                                   user_info_dc, pac_blob);
 225
 226         return nt_status;
 227 }
 228
 229 NTSTATUS samba_kdc_update_delegation_info_blob(TALLOC_CTX *mem_ctx,
 230                                 krb5_context context,
 231                                 const krb5_pac pac,
 232                                 const krb5_principal server_principal,
 233                                 const krb5_principal proxy_principal,
 234                                 DATA_BLOB *new_blob)
 235 {
 236         krb5_data old_data;
 237         DATA_BLOB old_blob;
 238         krb5_error_code ret;
 239         NTSTATUS nt_status;
 240         enum ndr_err_code ndr_err;
 241         union PAC_INFO info;
 242         struct PAC_CONSTRAINED_DELEGATION _d;
 243         struct PAC_CONSTRAINED_DELEGATION *d = NULL;
 244         char *server = NULL;
 245         char *proxy = NULL;
 246         uint32_t i;
 247         TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
 248
 249         if (tmp_ctx == NULL) {
 250                 return NT_STATUS_NO_MEMORY;
 251         }
 252
 253         ret = krb5_pac_get_buffer(context, pac, PAC_TYPE_CONSTRAINED_DELEGATION, &old_data);
 254         if (ret == ENOENT) {
 255                 ZERO_STRUCT(old_data);
 256         } else if (ret) {
 257                 talloc_free(tmp_ctx);
 258                 return NT_STATUS_UNSUCCESSFUL;
 259         }
 260
 261         old_blob.length = old_data.length;
 262         old_blob.data = (uint8_t *)old_data.data;
 263
 264         ZERO_STRUCT(info);
 265         if (old_blob.length > 0) {
 266                 ndr_err = ndr_pull_union_blob(&old_blob, mem_ctx,
 267                                 &info, PAC_TYPE_CONSTRAINED_DELEGATION,
 268                                 (ndr_pull_flags_fn_t)ndr_pull_PAC_INFO);
 269                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 270                         krb5_data_free(&old_data);
 271                         nt_status = ndr_map_error2ntstatus(ndr_err);
 272                         DEBUG(0,("can't parse the PAC LOGON_INFO: %s\n", nt_errstr(nt_status)));
 273                         talloc_free(tmp_ctx);
 274                         return nt_status;
 275                 }
 276         } else {
 277                 ZERO_STRUCT(_d);
 278                 info.constrained_delegation.info = &_d;
 279         }
 280         krb5_data_free(&old_data);
 281
 282         ret = krb5_unparse_name(context, server_principal, &server);
 283         if (ret) {
 284                 talloc_free(tmp_ctx);
 285                 return NT_STATUS_INTERNAL_ERROR;
 286         }
 287
 288         ret = krb5_unparse_name_flags(context, proxy_principal,
 289                                       KRB5_PRINCIPAL_UNPARSE_NO_REALM, &proxy);
 290         if (ret) {
 291                 SAFE_FREE(server);
 292                 talloc_free(tmp_ctx);
 293                 return NT_STATUS_INTERNAL_ERROR;
 294         }
 295
 296         d = info.constrained_delegation.info;
 297         i = d->num_transited_services;
 298         d->proxy_target.string = server;
 299         d->transited_services = talloc_realloc(mem_ctx, d->transited_services,
 300                                                struct lsa_String, i + 1);
 301         d->transited_services[i].string = proxy;
 302         d->num_transited_services = i + 1;
 303
 304         ndr_err = ndr_push_union_blob(new_blob, mem_ctx,
 305                                 &info, PAC_TYPE_CONSTRAINED_DELEGATION,
 306                                 (ndr_push_flags_fn_t)ndr_push_PAC_INFO);
 307         SAFE_FREE(server);
 308         SAFE_FREE(proxy);
 309         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 310                 krb5_data_free(&old_data);
 311                 nt_status = ndr_map_error2ntstatus(ndr_err);
 312                 DEBUG(0,("can't parse the PAC LOGON_INFO: %s\n", nt_errstr(nt_status)));
 313                 talloc_free(tmp_ctx);
 314                 return nt_status;
 315         }
 316
 317         talloc_free(tmp_ctx);
 318         return NT_STATUS_OK;
 319 }
 320
 321 /* this function allocates 'data' using malloc.
 322  * The caller is responsible for freeing it */
 323 void samba_kdc_build_edata_reply(NTSTATUS nt_status, DATA_BLOB *e_data)
 324 {
 325         PA_DATA pa;
 326         unsigned char *buf;
 327         size_t len;
 328         krb5_error_code ret = 0;
 329
 330         if (!e_data)
 331                 return;
 332
 333         pa.padata_type          = KRB5_PADATA_PW_SALT;
 334         pa.padata_value.length  = 12;
 335         pa.padata_value.data    = malloc(pa.padata_value.length);
 336         if (!pa.padata_value.data) {
 337                 e_data->length = 0;
 338                 e_data->data = NULL;
 339                 return;
 340         }
 341
 342         SIVAL(pa.padata_value.data, 0, NT_STATUS_V(nt_status));
 343         SIVAL(pa.padata_value.data, 4, 0);
 344         SIVAL(pa.padata_value.data, 8, 1);
 345
 346         ASN1_MALLOC_ENCODE(PA_DATA, buf, len, &pa, &len, ret);
 347         free(pa.padata_value.data);
 348
 349         e_data->data   = buf;
 350         e_data->length = len;
 351
 352         return;
 353 }
 354
 355 /* function to map policy errors */
 356 krb5_error_code samba_kdc_map_policy_err(NTSTATUS nt_status)
 357 {
 358         krb5_error_code ret;
 359
 360         if (NT_STATUS_EQUAL(nt_status, NT_STATUS_PASSWORD_MUST_CHANGE))
 361                 ret = KRB5KDC_ERR_KEY_EXPIRED;
 362         else if (NT_STATUS_EQUAL(nt_status, NT_STATUS_PASSWORD_EXPIRED))
 363                 ret = KRB5KDC_ERR_KEY_EXPIRED;
 364         else if (NT_STATUS_EQUAL(nt_status, NT_STATUS_ACCOUNT_EXPIRED))
 365                 ret = KRB5KDC_ERR_CLIENT_REVOKED;
 366         else if (NT_STATUS_EQUAL(nt_status, NT_STATUS_ACCOUNT_DISABLED))
 367                 ret = KRB5KDC_ERR_CLIENT_REVOKED;
 368         else if (NT_STATUS_EQUAL(nt_status, NT_STATUS_INVALID_LOGON_HOURS))
 369                 ret = KRB5KDC_ERR_CLIENT_REVOKED;
 370         else if (NT_STATUS_EQUAL(nt_status, NT_STATUS_ACCOUNT_LOCKED_OUT))
 371                 ret = KRB5KDC_ERR_CLIENT_REVOKED;
 372         else if (NT_STATUS_EQUAL(nt_status, NT_STATUS_INVALID_WORKSTATION))
 373                 ret = KRB5KDC_ERR_POLICY;
 374         else
 375                 ret = KRB5KDC_ERR_POLICY;
 376
 377         return ret;
 378 }
 379
 380 /* Given a kdc entry, consult the account_ok routine in auth/auth_sam.c
 381  * for consistency */
 382 NTSTATUS samba_kdc_check_client_access(struct samba_kdc_entry *kdc_entry,
 383                                        const char *client_name,
 384                                        const char *workstation,
 385                                        bool password_change)
 386 {
 387         TALLOC_CTX *tmp_ctx;
 388         NTSTATUS nt_status;
 389
 390         tmp_ctx = talloc_named(NULL, 0, "samba_kdc_check_client_access");
 391         if (!tmp_ctx) {
 392                 return NT_STATUS_NO_MEMORY;
 393         }
 394
 395         /* we allow all kinds of trusts here */
 396         nt_status = authsam_account_ok(tmp_ctx,
 397                                        kdc_entry->kdc_db_ctx->samdb,
 398                                        MSV1_0_ALLOW_SERVER_TRUST_ACCOUNT |
 399                                        MSV1_0_ALLOW_WORKSTATION_TRUST_ACCOUNT,
 400                                        kdc_entry->realm_dn, kdc_entry->msg,
 401                                        workstation, client_name,
 402                                        true, password_change);
 403
 404         talloc_free(tmp_ctx);
 405         return nt_status;
 406 }
 407