source4/kdc/mit_samba.c

   1 /*
   2    MIT-Samba4 library
   3
   4    Copyright (c) 2010, Simo Sorce <idra@samba.org>
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include "includes.h"
  21 #include "param/param.h"
  22 #include "dsdb/samdb/samdb.h"
  23 #include "auth/auth.h"
  24 #include "auth/credentials/credentials.h"
  25 #include "system/kerberos.h"
  26 #include "hdb.h"
  27 #include "mit_samba_interface.h"
  28 #include "auth/kerberos/kerberos.h"
  29 #include "kdc/samba_kdc.h"
  30 #include "kdc/pac-glue.h"
  31 #include "kdc/db-glue.h"
  32
  33 const int mit_samba_interface_version = MIT_SAMBA_INTERFACE_VERSION;
  34
  35 struct mit_samba_context {
  36         struct auth_session_info *session_info;
  37
  38         /* for compat with hdb plugin common code */
  39         krb5_context context;
  40         struct samba_kdc_db_context *db_ctx;
  41 };
  42
  43 static void mit_samba_context_free(struct mit_samba_context *ctx)
  44 {
  45         /* free heimdal's krb5_context */
  46         if (ctx->context) {
  47                 krb5_free_context(ctx->context);
  48         }
  49
  50         /* then free everything else */
  51         talloc_free(ctx);
  52 }
  53
  54 static int mit_samba_context_init(struct mit_samba_context **_ctx)
  55 {
  56         struct mit_samba_context *ctx;
  57         const char *s4_conf_file;
  58         int ret;
  59
  60
  61         ctx = talloc(NULL, struct mit_samba_context);
  62         if (!ctx) {
  63                 ret = ENOMEM;
  64                 goto done;
  65         }
  66
  67         ctx->db_ctx = talloc_zero(ctx, struct samba_kdc_db_context);
  68         if (!ctx->db_ctx) {
  69                 ret = ENOMEM;
  70                 goto done;
  71         }
  72
  73         ctx->db_ctx->ev_ctx = tevent_context_init(ctx);
  74         if (!ctx->db_ctx->ev_ctx) {
  75                 ret = ENOMEM;
  76                 goto done;
  77         }
  78         ctx->db_ctx->lp_ctx = loadparm_init(ctx);
  79         if (!ctx->db_ctx->lp_ctx) {
  80                 ret = ENOMEM;
  81                 goto done;
  82         }
  83
  84         /* init s4 configuration */
  85         s4_conf_file = lpcfg_configfile(ctx->db_ctx->lp_ctx);
  86         if (s4_conf_file) {
  87                 lpcfg_load(ctx->db_ctx->lp_ctx, s4_conf_file);
  88         } else {
  89                 lpcfg_load_default(ctx->db_ctx->lp_ctx);
  90         }
  91
  92         ctx->session_info = system_session(ctx->db_ctx->lp_ctx);
  93         if (!ctx->session_info) {
  94                 ret = EFAULT;
  95                 goto done;
  96         }
  97
  98         cli_credentials_set_kerberos_state(ctx->session_info->credentials,
  99                                            CRED_DONT_USE_KERBEROS);
 100
 101         ctx->db_ctx->samdb = samdb_connect(ctx->db_ctx,
 102                                            ctx->db_ctx->ev_ctx,
 103                                            ctx->db_ctx->lp_ctx,
 104                                            ctx->session_info);
 105         if (!ctx->db_ctx->samdb) {
 106                 ret = EFAULT;
 107                 goto done;
 108         }
 109
 110         /* init heimdal's krb_context and log facilities */
 111         ret = smb_krb5_init_context_basic(ctx,
 112                                           ctx->db_ctx->ev_ctx,
 113                                           ctx->db_ctx->lp_ctx,
 114                                           &ctx->context);
 115         if (ret) {
 116                 goto done;
 117         }
 118
 119         ret = 0;
 120
 121 done:
 122         if (ret) {
 123                 mit_samba_context_free(ctx);
 124         } else {
 125                 *_ctx = ctx;
 126         }
 127         return ret;
 128 }
 129
 130
 131 static int mit_samba_get_principal(struct mit_samba_context *ctx,
 132                                    char *principal_string,
 133                                    unsigned int flags,
 134                                    hdb_entry_ex **_hentry)
 135 {
 136         krb5_principal principal;
 137         hdb_entry_ex *hentry;
 138         int ret;
 139
 140         hentry = talloc(ctx, hdb_entry_ex);
 141         if (!hentry) {
 142                 return ENOMEM;
 143         }
 144
 145         ret = krb5_parse_name(ctx->context, principal_string, &principal);
 146         if (ret) {
 147                 goto done;
 148         }
 149
 150         ret = samba_kdc_fetch(ctx->context, ctx->db_ctx,
 151                               principal, flags, hentry);
 152
 153         krb5_free_principal(ctx->context, principal);
 154
 155 done:
 156         if (ret) {
 157                 talloc_free(hentry);
 158         } else {
 159                 talloc_steal(hentry->ctx, hentry);
 160                 *_hentry = hentry;
 161         }
 162         return ret;
 163 }
 164
 165 static int mit_samba_get_firstkey(struct mit_samba_context *ctx,
 166                                   hdb_entry_ex **_hentry)
 167 {
 168         hdb_entry_ex *hentry;
 169         int ret;
 170
 171         hentry = talloc(ctx, hdb_entry_ex);
 172         if (!hentry) {
 173                 return ENOMEM;
 174         }
 175
 176         ret = samba_kdc_firstkey(ctx->context, ctx->db_ctx, hentry);
 177
 178         if (ret) {
 179                 talloc_free(hentry);
 180         } else {
 181                 talloc_steal(hentry->ctx, hentry);
 182                 *_hentry = hentry;
 183         }
 184         return ret;
 185 }
 186
 187 static int mit_samba_get_nextkey(struct mit_samba_context *ctx,
 188                                  hdb_entry_ex **_hentry)
 189 {
 190         hdb_entry_ex *hentry;
 191         int ret;
 192
 193         hentry = talloc(ctx, hdb_entry_ex);
 194         if (!hentry) {
 195                 return ENOMEM;
 196         }
 197
 198         ret = samba_kdc_nextkey(ctx->context, ctx->db_ctx, hentry);
 199
 200         if (ret) {
 201                 talloc_free(hentry);
 202         } else {
 203                 talloc_steal(hentry->ctx, hentry);
 204                 *_hentry = hentry;
 205         }
 206         return ret;
 207 }
 208
 209 static int mit_samba_get_pac_data(struct mit_samba_context *ctx,
 210                                   hdb_entry_ex *client,
 211                                   DATA_BLOB *data)
 212 {
 213         TALLOC_CTX *tmp_ctx;
 214         DATA_BLOB *pac_blob;
 215         NTSTATUS nt_status;
 216
 217         tmp_ctx = talloc_named(ctx, 0, "mit_samba_get_pac_data context");
 218         if (!tmp_ctx) {
 219                 return ENOMEM;
 220         }
 221
 222         nt_status = samba_kdc_get_pac_blob(tmp_ctx, client, &pac_blob);
 223         if (!NT_STATUS_IS_OK(nt_status)) {
 224                 talloc_free(tmp_ctx);
 225                 return EINVAL;
 226         }
 227
 228         data->data = (uint8_t *)malloc(pac_blob->length);
 229         if (!data->data) {
 230                 talloc_free(tmp_ctx);
 231                 return ENOMEM;
 232         }
 233         memcpy(data->data, pac_blob->data, pac_blob->length);
 234         data->length = pac_blob->length;
 235
 236         talloc_free(tmp_ctx);
 237         return 0;
 238 }
 239
 240 static int mit_samba_update_pac_data(struct mit_samba_context *ctx,
 241                                      hdb_entry_ex *client,
 242                                      DATA_BLOB *pac_data,
 243                                      DATA_BLOB *logon_data)
 244 {
 245         TALLOC_CTX *tmp_ctx;
 246         DATA_BLOB *logon_blob;
 247         krb5_error_code code;
 248         NTSTATUS nt_status;
 249         krb5_pac pac = NULL;
 250         int ret;
 251
 252         /* The user account may be set not to want the PAC */
 253         if (client && !samba_princ_needs_pac(client)) {
 254                 return EINVAL;
 255         }
 256
 257         tmp_ctx = talloc_named(ctx, 0, "mit_samba_update_pac_data context");
 258         if (!tmp_ctx) {
 259                 return ENOMEM;
 260         }
 261
 262         logon_blob = talloc_zero(tmp_ctx, DATA_BLOB);
 263         if (!logon_blob) {
 264                 ret = ENOMEM;
 265                 goto done;
 266         }
 267
 268         code = krb5_pac_parse(ctx->context,
 269                               pac_data->data, pac_data->length, &pac);
 270         if (code) {
 271                 ret = EINVAL;
 272                 goto done;
 273         }
 274
 275         nt_status = samba_kdc_update_pac_blob(tmp_ctx, ctx->context,
 276                                               &pac, logon_blob);
 277         if (!NT_STATUS_IS_OK(nt_status)) {
 278                 DEBUG(0, ("Building PAC failed: %s\n",
 279                           nt_errstr(nt_status)));
 280                 ret = EINVAL;
 281                 goto done;
 282         }
 283
 284         logon_data->data = (uint8_t *)malloc(logon_blob->length);
 285         if (!logon_data->data) {
 286                 ret = ENOMEM;
 287                 goto done;
 288         }
 289         memcpy(logon_data->data, logon_blob->data, logon_blob->length);
 290         logon_data->length = logon_blob->length;
 291
 292         ret = 0;
 293
 294 done:
 295         if (pac) krb5_pac_free(ctx->context, pac);
 296         talloc_free(tmp_ctx);
 297         return ret;
 298 }
 299
 300 static int mit_samba_check_client_access(struct mit_samba_context *ctx,
 301                                          hdb_entry_ex *client,
 302                                          const char *client_name,
 303                                          hdb_entry_ex *server,
 304                                          const char *server_name,
 305                                          const char *netbios_name,
 306                                          bool password_change,
 307                                          DATA_BLOB *e_data)
 308 {
 309         struct samba_kdc_entry *kdc_entry;
 310         NTSTATUS nt_status;
 311
 312         kdc_entry = talloc_get_type(client->ctx, struct samba_kdc_entry);
 313
 314         nt_status = samba_kdc_check_client_access(kdc_entry,
 315                                                   client_name,
 316                                                   netbios_name,
 317                                                   password_change);
 318
 319         if (!NT_STATUS_IS_OK(nt_status)) {
 320                 if (NT_STATUS_EQUAL(nt_status, NT_STATUS_NO_MEMORY)) {
 321                         return ENOMEM;
 322                 }
 323
 324                 samba_kdc_build_edata_reply(nt_status, e_data);
 325
 326                 return samba_kdc_map_policy_err(nt_status);
 327         }
 328
 329         return 0;
 330 }
 331
 332 static int mit_samba_check_s4u2proxy(struct mit_samba_context *ctx,
 333                                      hdb_entry_ex *entry,
 334                                      const char *target_name,
 335                                      bool is_nt_enterprise_name)
 336 {
 337         krb5_principal target_principal;
 338         int flags = 0;
 339         int ret;
 340
 341         if (is_nt_enterprise_name) {
 342                 flags = KRB5_PRINCIPAL_PARSE_ENTERPRISE;
 343         }
 344
 345         ret = krb5_parse_name_flags(ctx->context, target_name,
 346                                     flags, &target_principal);
 347         if (ret) {
 348                 return ret;
 349         }
 350
 351         ret = samba_kdc_check_identical_client_and_server(ctx->context,
 352                                                           ctx->db_ctx,
 353                                                           entry,
 354                                                           target_principal);
 355
 356         krb5_free_principal(ctx->context, target_principal);
 357
 358         return ret;
 359 }
 360
 361 struct mit_samba_function_table mit_samba_function_table = {
 362         mit_samba_context_init,
 363         mit_samba_context_free,
 364         mit_samba_get_principal,
 365         mit_samba_get_firstkey,
 366         mit_samba_get_nextkey,
 367         mit_samba_get_pac_data,
 368         mit_samba_update_pac_data,
 369         mit_samba_check_client_access,
 370         mit_samba_check_s4u2proxy
 371 };