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
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  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 "kdc/kdc.h"
  25 #include "dsdb/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
  32 struct krb5_dh_moduli;
  33 struct _krb5_krb_auth_data;
  34
  35 krb5_error_code samba_kdc_plugin_init(krb5_context context, void **ptr)
  36 {
  37         *ptr = NULL;
  38         return 0;
  39 }
  40
  41 void    samba_kdc_plugin_fini(void *ptr)
  42 {
  43         return;
  44 }
  45
  46 static krb5_error_code make_pac(krb5_context context,
  47                                 TALLOC_CTX *mem_ctx,
  48                                 struct auth_serversupplied_info *server_info,
  49                                 krb5_pac *pac)
  50 {
  51         struct PAC_LOGON_INFO_CTR logon_info;
  52         struct netr_SamInfo3 *info3;
  53         krb5_data pac_data;
  54         NTSTATUS nt_status;
  55         DATA_BLOB pac_out;
  56         krb5_error_code ret;
  57
  58         ZERO_STRUCT(logon_info);
  59
  60         nt_status = auth_convert_server_info_saminfo3(mem_ctx, server_info, &info3);
  61         if (!NT_STATUS_IS_OK(nt_status)) {
  62                 DEBUG(1, ("Getting Samba info failed: %s\n", nt_errstr(nt_status)));
  63                 return EINVAL;
  64         }
  65
  66         logon_info.info = talloc_zero(mem_ctx, struct PAC_LOGON_INFO);
  67         if (!mem_ctx) {
  68                 return ENOMEM;
  69         }
  70
  71         logon_info.info->info3 = *info3;
  72
  73         nt_status = ndr_push_struct_blob(&pac_out, mem_ctx, &logon_info,
  74                                          (ndr_push_flags_fn_t)ndr_push_PAC_LOGON_INFO_CTR);
  75         if (!NT_STATUS_IS_OK(nt_status)) {
  76                 DEBUG(1, ("PAC (presig) push failed: %s\n", nt_errstr(nt_status)));
  77                 return EINVAL;
  78         }
  79
  80         ret = krb5_data_copy(&pac_data, pac_out.data, pac_out.length);
  81         if (ret != 0) {
  82                 return ret;
  83         }
  84
  85         ret = krb5_pac_init(context, pac);
  86         if (ret != 0) {
  87                 krb5_data_free(&pac_data);
  88                 return ret;
  89         }
  90
  91         ret = krb5_pac_add_buffer(context, *pac, PAC_TYPE_LOGON_INFO, &pac_data);
  92         krb5_data_free(&pac_data);
  93         if (ret != 0) {
  94                 return ret;
  95         }
  96
  97         return ret;
  98 }
  99
 100 /* Given the right private pointer from hdb_ldb, get a PAC from the attached ldb messages */
 101 krb5_error_code samba_kdc_get_pac(void *priv,
 102                                   krb5_context context,
 103                                   struct hdb_entry_ex *client,
 104                                   krb5_pac *pac)
 105 {
 106         krb5_error_code ret;
 107         NTSTATUS nt_status;
 108         struct auth_serversupplied_info *server_info;
 109         struct hdb_ldb_private *private = talloc_get_type(client->ctx, struct hdb_ldb_private);
 110         TALLOC_CTX *mem_ctx = talloc_named(private, 0, "samba_get_pac context");
 111         unsigned int userAccountControl;
 112
 113         if (!mem_ctx) {
 114                 return ENOMEM;
 115         }
 116
 117         /* The user account may be set not to want the PAC */
 118         userAccountControl = ldb_msg_find_attr_as_uint(private->msg, "userAccountControl", 0);
 119         if (userAccountControl & UF_NO_AUTH_DATA_REQUIRED) {
 120                 *pac = NULL;
 121                 return 0;
 122         }
 123
 124         nt_status = authsam_make_server_info(mem_ctx, private->samdb,
 125                                              private->msg,
 126                                              private->realm_ref_msg,
 127                                              data_blob(NULL, 0),
 128                                              data_blob(NULL, 0),
 129                                              &server_info);
 130         if (!NT_STATUS_IS_OK(nt_status)) {
 131                 DEBUG(0, ("Getting user info for PAC failed: %s\n",
 132                           nt_errstr(nt_status)));
 133                 return ENOMEM;
 134         }
 135
 136         ret = make_pac(context, mem_ctx, server_info, pac);
 137
 138         talloc_free(mem_ctx);
 139         return ret;
 140 }
 141
 142 /* Resign (and reform, including possibly new groups) a PAC */
 143
 144 krb5_error_code samba_kdc_reget_pac(void *priv, krb5_context context,
 145                                 const krb5_principal client_principal,
 146                                 struct hdb_entry_ex *client,
 147                                 struct hdb_entry_ex *server, krb5_pac *pac)
 148 {
 149         NTSTATUS nt_status;
 150         krb5_error_code ret;
 151
 152         unsigned int userAccountControl;
 153
 154         struct hdb_ldb_private *private = talloc_get_type(server->ctx, struct hdb_ldb_private);
 155         krb5_data k5pac_in;
 156         DATA_BLOB pac_in;
 157
 158         struct PAC_LOGON_INFO_CTR logon_info;
 159         union netr_Validation validation;
 160         struct auth_serversupplied_info *server_info_out;
 161
 162         TALLOC_CTX *mem_ctx = talloc_named(private, 0, "samba_get_pac context");
 163
 164         if (!mem_ctx) {
 165                 return ENOMEM;
 166         }
 167
 168         /* The service account may be set not to want the PAC */
 169         userAccountControl = ldb_msg_find_attr_as_uint(private->msg, "userAccountControl", 0);
 170         if (userAccountControl & UF_NO_AUTH_DATA_REQUIRED) {
 171                 *pac = NULL;
 172                 return 0;
 173         }
 174
 175         ret = krb5_pac_get_buffer(context, *pac, PAC_TYPE_LOGON_INFO, &k5pac_in);
 176         if (ret != 0) {
 177                 return ret;
 178         }
 179
 180         pac_in = data_blob_talloc(mem_ctx, k5pac_in.data, k5pac_in.length);
 181         krb5_data_free(&k5pac_in);
 182         if (!pac_in.data) {
 183                 talloc_free(mem_ctx);
 184                 return ENOMEM;
 185         }
 186
 187         nt_status = ndr_pull_struct_blob(&pac_in, mem_ctx, &logon_info,
 188                                       (ndr_pull_flags_fn_t)ndr_pull_PAC_LOGON_INFO_CTR);
 189         if (!NT_STATUS_IS_OK(nt_status) || !logon_info.info) {
 190                 DEBUG(0,("can't parse the PAC LOGON_INFO: %s\n", nt_errstr(nt_status)));
 191                 talloc_free(mem_ctx);
 192                 return EINVAL;
 193         }
 194
 195         /* Pull this right into the normal auth sysstem structures */
 196         validation.sam3 = &logon_info.info->info3;
 197         nt_status = make_server_info_netlogon_validation(mem_ctx,
 198                                                          "",
 199                                                          3, &validation,
 200                                                          &server_info_out);
 201         if (!NT_STATUS_IS_OK(nt_status)) {
 202                 talloc_free(mem_ctx);
 203                 return ENOMEM;
 204         }
 205
 206         /* We will compleatly regenerate this pac */
 207         krb5_pac_free(context, *pac);
 208
 209         ret = make_pac(context, mem_ctx, server_info_out, pac);
 210
 211         talloc_free(mem_ctx);
 212         return ret;
 213 }
 214
 215 /* Given an hdb entry (and in particular it's private member), consult
 216  * the account_ok routine in auth/auth_sam.c for consistancy */
 217
 218
 219 krb5_error_code samba_kdc_check_client_access(void *priv,
 220                                               krb5_context context, hdb_entry_ex *entry_ex,
 221                                               KDC_REQ *req)
 222 {
 223         krb5_error_code ret;
 224         NTSTATUS nt_status;
 225         TALLOC_CTX *tmp_ctx = talloc_new(entry_ex->ctx);
 226         struct hdb_ldb_private *private = talloc_get_type(entry_ex->ctx, struct hdb_ldb_private);
 227         char *name, *workstation = NULL;
 228         HostAddresses *addresses = req->req_body.addresses;
 229         int i;
 230
 231         if (!tmp_ctx) {
 232                 return ENOMEM;
 233         }
 234
 235         ret = krb5_unparse_name(context, entry_ex->entry.principal, &name);
 236         if (ret != 0) {
 237                 talloc_free(tmp_ctx);
 238                 return ret;
 239         }
 240
 241         if (addresses) {
 242                 for (i=0; i < addresses->len; i++) {
 243                         if (addresses->val->addr_type == KRB5_ADDRESS_NETBIOS) {
 244                                 workstation = talloc_strndup(tmp_ctx, addresses->val->address.data, MIN(addresses->val->address.length, 15));
 245                                 if (workstation) {
 246                                         break;
 247                                 }
 248                         }
 249                 }
 250         }
 251
 252         /* Strip space padding */
 253         if (workstation) {
 254                 i = MIN(strlen(workstation), 15);
 255                 for (; i > 0 && workstation[i - 1] == ' '; i--) {
 256                         workstation[i - 1] = '\0';
 257                 }
 258         }
 259
 260         nt_status = authsam_account_ok(tmp_ctx,
 261                                        private->samdb,
 262                                        MSV1_0_ALLOW_SERVER_TRUST_ACCOUNT | MSV1_0_ALLOW_WORKSTATION_TRUST_ACCOUNT,
 263                                        private->msg,
 264                                        private->realm_ref_msg,
 265                                        workstation,
 266                                        name);
 267         free(name);
 268
 269         /* TODO:  Need a more complete mapping of NTSTATUS to krb5kdc errors */
 270
 271         if (!NT_STATUS_IS_OK(nt_status)) {
 272                 return KRB5KDC_ERR_POLICY;
 273         }
 274         return 0;
 275 }
 276