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 "lib/ldb/include/ldb.h"
  27 #include "librpc/gen_ndr/ndr_krb5pac.h"
  28 #include "librpc/gen_ndr/krb5pac.h"
  29 #include "auth/auth.h"
  30 #include "auth/auth_sam.h"
  31 #include "auth/auth_sam_reply.h"
  32 #include "kdc/kdc-glue.h"
  33 #include "param/param.h"
  34
  35 static
  36 NTSTATUS samba_get_logon_info_pac_blob(TALLOC_CTX *mem_ctx,
  37                                        struct auth_serversupplied_info *info,
  38                                        DATA_BLOB *pac_data)
  39 {
  40         struct netr_SamInfo3 *info3;
  41         union PAC_INFO pac_info;
  42         enum ndr_err_code ndr_err;
  43         NTSTATUS nt_status;
  44
  45         ZERO_STRUCT(pac_info);
  46
  47         nt_status = auth_convert_server_info_saminfo3(mem_ctx, info, &info3);
  48         if (!NT_STATUS_IS_OK(nt_status)) {
  49                 DEBUG(1, ("Getting Samba info failed: %s\n",
  50                           nt_errstr(nt_status)));
  51                 return nt_status;
  52         }
  53
  54         pac_info.logon_info.info = talloc_zero(mem_ctx, struct PAC_LOGON_INFO);
  55         if (!mem_ctx) {
  56                 return NT_STATUS_NO_MEMORY;
  57         }
  58
  59         pac_info.logon_info.info->info3 = *info3;
  60
  61         ndr_err = ndr_push_union_blob(pac_data, mem_ctx, &pac_info,
  62                                       PAC_TYPE_LOGON_INFO,
  63                                       (ndr_push_flags_fn_t)ndr_push_PAC_INFO);
  64         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
  65                 nt_status = ndr_map_error2ntstatus(ndr_err);
  66                 DEBUG(1, ("PAC (presig) push failed: %s\n",
  67                           nt_errstr(nt_status)));
  68                 return nt_status;
  69         }
  70
  71         return NT_STATUS_OK;
  72 }
  73
  74 krb5_error_code samba_make_krb5_pac(krb5_context context,
  75                                     DATA_BLOB *pac_blob,
  76                                     krb5_pac *pac)
  77 {
  78         krb5_data pac_data;
  79         krb5_error_code ret;
  80
  81         /* The user account may be set not to want the PAC */
  82         if (!pac_blob) {
  83                 return 0;
  84         }
  85
  86         ret = krb5_data_copy(&pac_data, pac_blob->data, pac_blob->length);
  87         if (ret != 0) {
  88                 return ret;
  89         }
  90
  91         ret = krb5_pac_init(context, pac);
  92         if (ret != 0) {
  93                 krb5_data_free(&pac_data);
  94                 return ret;
  95         }
  96
  97         ret = krb5_pac_add_buffer(context, *pac, PAC_TYPE_LOGON_INFO, &pac_data);
  98         krb5_data_free(&pac_data);
  99         if (ret != 0) {
 100                 return ret;
 101         }
 102
 103         return ret;
 104 }
 105
 106 bool samba_princ_needs_pac(struct hdb_entry_ex *princ)
 107 {
 108
 109         struct samba_kdc_entry *p = talloc_get_type(princ->ctx, struct samba_kdc_entry);
 110         uint32_t userAccountControl;
 111
 112
 113         /* The service account may be set not to want the PAC */
 114         userAccountControl = ldb_msg_find_attr_as_uint(p->msg, "userAccountControl", 0);
 115         if (userAccountControl & UF_NO_AUTH_DATA_REQUIRED) {
 116                 return false;
 117         }
 118
 119         return true;
 120 }
 121
 122 /* Was the krbtgt an RODC (and we are not) */
 123 bool samba_krbtgt_was_untrusted_rodc(struct hdb_entry_ex *princ)
 124 {
 125
 126         struct samba_kdc_entry *p = talloc_get_type(princ->ctx, struct samba_kdc_entry);
 127         int rodc_krbtgt_number;
 128
 129         /* Determine if this was printed by an RODC */
 130         rodc_krbtgt_number = ldb_msg_find_attr_as_int(p->msg, "msDS-SecondaryKrbTgtNumber", -1);
 131         if (rodc_krbtgt_number == -1) {
 132                 return false;
 133         } else if (rodc_krbtgt_number != p->kdc_db_ctx->my_krbtgt_number) {
 134                 return true;
 135         }
 136
 137         return false;
 138 }
 139
 140 NTSTATUS samba_kdc_get_pac_blob(TALLOC_CTX *mem_ctx,
 141                                 struct hdb_entry_ex *client,
 142                                 DATA_BLOB **_pac_blob)
 143 {
 144         struct samba_kdc_entry *p = talloc_get_type(client->ctx, struct samba_kdc_entry);
 145         struct auth_serversupplied_info *server_info;
 146         DATA_BLOB *pac_blob;
 147         NTSTATUS nt_status;
 148
 149         /* The user account may be set not to want the PAC */
 150         if ( ! samba_princ_needs_pac(client)) {
 151                 *_pac_blob = NULL;
 152                 return NT_STATUS_OK;
 153         }
 154
 155         pac_blob = talloc_zero(mem_ctx, DATA_BLOB);
 156         if (!pac_blob) {
 157                 return NT_STATUS_NO_MEMORY;
 158         }
 159
 160         nt_status = authsam_make_server_info(mem_ctx, p->kdc_db_ctx->samdb,
 161                                              lpcfg_netbios_name(p->kdc_db_ctx->lp_ctx),
 162                                              lpcfg_sam_name(p->kdc_db_ctx->lp_ctx),
 163                                              p->realm_dn,
 164                                              p->msg,
 165                                              data_blob(NULL, 0),
 166                                              data_blob(NULL, 0),
 167                                              &server_info);
 168         if (!NT_STATUS_IS_OK(nt_status)) {
 169                 DEBUG(0, ("Getting user info for PAC failed: %s\n",
 170                           nt_errstr(nt_status)));
 171                 return nt_status;
 172         }
 173
 174         nt_status = samba_get_logon_info_pac_blob(mem_ctx, server_info, pac_blob);
 175         if (!NT_STATUS_IS_OK(nt_status)) {
 176                 DEBUG(0, ("Building PAC failed: %s\n",
 177                           nt_errstr(nt_status)));
 178                 return nt_status;
 179         }
 180
 181         *_pac_blob = pac_blob;
 182         return NT_STATUS_OK;
 183 }
 184
 185 NTSTATUS samba_kdc_update_pac_blob(TALLOC_CTX *mem_ctx,
 186                                    krb5_context context,
 187                                    krb5_pac *pac, DATA_BLOB *pac_blob)
 188 {
 189         struct auth_serversupplied_info *server_info;
 190         krb5_error_code ret;
 191         NTSTATUS nt_status;
 192
 193         ret = kerberos_pac_to_server_info(mem_ctx, *pac,
 194                                           context, &server_info);
 195         if (ret) {
 196                 return NT_STATUS_UNSUCCESSFUL;
 197         }
 198
 199         nt_status = samba_get_logon_info_pac_blob(mem_ctx,
 200                                                   server_info, pac_blob);
 201
 202         return nt_status;
 203 }
 204
 205 /* this function allocates 'data' using malloc.
 206  * The caller is responsible for freeing it */
 207 void samba_kdc_build_edata_reply(NTSTATUS nt_status, DATA_BLOB *e_data)
 208 {
 209         PA_DATA pa;
 210         unsigned char *buf;
 211         size_t len;
 212         krb5_error_code ret = 0;
 213
 214         if (!e_data)
 215                 return;
 216
 217         pa.padata_type          = KRB5_PADATA_PW_SALT;
 218         pa.padata_value.length  = 12;
 219         pa.padata_value.data    = malloc(pa.padata_value.length);
 220         if (!pa.padata_value.data) {
 221                 e_data->length = 0;
 222                 e_data->data = NULL;
 223                 return;
 224         }
 225
 226         SIVAL(pa.padata_value.data, 0, NT_STATUS_V(nt_status));
 227         SIVAL(pa.padata_value.data, 4, 0);
 228         SIVAL(pa.padata_value.data, 8, 1);
 229
 230         ASN1_MALLOC_ENCODE(PA_DATA, buf, len, &pa, &len, ret);
 231         free(pa.padata_value.data);
 232
 233         e_data->data   = buf;
 234         e_data->length = len;
 235
 236         return;
 237 }
 238
 239 /* function to map policy errors */
 240 krb5_error_code samba_kdc_map_policy_err(NTSTATUS nt_status)
 241 {
 242         krb5_error_code ret;
 243
 244         if (NT_STATUS_EQUAL(nt_status, NT_STATUS_PASSWORD_MUST_CHANGE))
 245                 ret = KRB5KDC_ERR_KEY_EXPIRED;
 246         else if (NT_STATUS_EQUAL(nt_status, NT_STATUS_PASSWORD_EXPIRED))
 247                 ret = KRB5KDC_ERR_KEY_EXPIRED;
 248         else if (NT_STATUS_EQUAL(nt_status, NT_STATUS_ACCOUNT_EXPIRED))
 249                 ret = KRB5KDC_ERR_CLIENT_REVOKED;
 250         else if (NT_STATUS_EQUAL(nt_status, NT_STATUS_ACCOUNT_DISABLED))
 251                 ret = KRB5KDC_ERR_CLIENT_REVOKED;
 252         else if (NT_STATUS_EQUAL(nt_status, NT_STATUS_INVALID_LOGON_HOURS))
 253                 ret = KRB5KDC_ERR_CLIENT_REVOKED;
 254         else if (NT_STATUS_EQUAL(nt_status, NT_STATUS_ACCOUNT_LOCKED_OUT))
 255                 ret = KRB5KDC_ERR_CLIENT_REVOKED;
 256         else if (NT_STATUS_EQUAL(nt_status, NT_STATUS_INVALID_WORKSTATION))
 257                 ret = KRB5KDC_ERR_POLICY;
 258         else
 259                 ret = KRB5KDC_ERR_POLICY;
 260
 261         return ret;
 262 }
 263
 264 /* Given a kdc entry, consult the account_ok routine in auth/auth_sam.c
 265  * for consistency */
 266 NTSTATUS samba_kdc_check_client_access(struct samba_kdc_entry *kdc_entry,
 267                                        const char *client_name,
 268                                        const char *workstation,
 269                                        bool password_change)
 270 {
 271         TALLOC_CTX *tmp_ctx;
 272         NTSTATUS nt_status;
 273
 274         tmp_ctx = talloc_named(NULL, 0, "samba_kdc_check_client_access");
 275         if (!tmp_ctx) {
 276                 return NT_STATUS_NO_MEMORY;
 277         }
 278
 279         /* we allow all kinds of trusts here */
 280         nt_status = authsam_account_ok(tmp_ctx,
 281                                        kdc_entry->kdc_db_ctx->samdb,
 282                                        MSV1_0_ALLOW_SERVER_TRUST_ACCOUNT |
 283                                        MSV1_0_ALLOW_WORKSTATION_TRUST_ACCOUNT,
 284                                        kdc_entry->realm_dn, kdc_entry->msg,
 285                                        workstation, client_name,
 286                                        true, password_change);
 287
 288         talloc_free(tmp_ctx);
 289         return nt_status;
 290 }
 291