source/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 2 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, write to the Free Software
  21    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  22 */
  23
  24 #include "includes.h"
  25 #include "kdc/kdc.h"
  26 #include "dsdb/common/flags.h"
  27 #include "lib/ldb/include/ldb.h"
  28 #include "librpc/gen_ndr/ndr_krb5pac.h"
  29 #include "librpc/gen_ndr/krb5pac.h"
  30 #include "auth/auth.h"
  31 #include "auth/auth_sam.h"
  32
  33 struct krb5_dh_moduli;
  34 struct _krb5_krb_auth_data;
  35
  36 krb5_error_code samba_kdc_plugin_init(krb5_context context, void **ptr)
  37 {
  38         *ptr = NULL;
  39         return 0;
  40 }
  41
  42 void    samba_kdc_plugin_fini(void *ptr)
  43 {
  44         return;
  45 }
  46
  47 static krb5_error_code make_pac(krb5_context context,
  48                                 TALLOC_CTX *mem_ctx,
  49                                 struct auth_serversupplied_info *server_info,
  50                                 krb5_pac *pac)
  51 {
  52         struct PAC_LOGON_INFO_CTR logon_info;
  53         struct netr_SamInfo3 *info3;
  54         krb5_data pac_data;
  55         NTSTATUS nt_status;
  56         DATA_BLOB pac_out;
  57         krb5_error_code ret;
  58
  59         ZERO_STRUCT(logon_info);
  60
  61         nt_status = auth_convert_server_info_saminfo3(mem_ctx, server_info, &info3);
  62         if (!NT_STATUS_IS_OK(nt_status)) {
  63                 DEBUG(1, ("Getting Samba info failed: %s\n", nt_errstr(nt_status)));
  64                 return EINVAL;
  65         }
  66
  67         logon_info.info = talloc_zero(mem_ctx, struct PAC_LOGON_INFO);
  68         if (!mem_ctx) {
  69                 return ENOMEM;
  70         }
  71
  72         logon_info.info->info3 = *info3;
  73
  74         nt_status = ndr_push_struct_blob(&pac_out, mem_ctx, &logon_info,
  75                                          (ndr_push_flags_fn_t)ndr_push_PAC_LOGON_INFO_CTR);
  76         if (!NT_STATUS_IS_OK(nt_status)) {
  77                 DEBUG(1, ("PAC (presig) push failed: %s\n", nt_errstr(nt_status)));
  78                 return EINVAL;
  79         }
  80
  81         ret = krb5_data_copy(&pac_data, pac_out.data, pac_out.length);
  82         if (ret != 0) {
  83                 return ret;
  84         }
  85
  86         ret = krb5_pac_init(context, pac);
  87         if (ret != 0) {
  88                 krb5_data_free(&pac_data);
  89                 return ret;
  90         }
  91
  92         ret = krb5_pac_add_buffer(context, *pac, PAC_TYPE_LOGON_INFO, &pac_data);
  93         krb5_data_free(&pac_data);
  94         if (ret != 0) {
  95                 return ret;
  96         }
  97
  98         return ret;
  99 }
 100
 101 /* Given the right private pointer from hdb_ldb, get a PAC from the attached ldb messages */
 102 krb5_error_code samba_kdc_get_pac(void *priv,
 103                                   krb5_context context,
 104                                   struct hdb_entry_ex *client,
 105                                   krb5_pac *pac)
 106 {
 107         krb5_error_code ret;
 108         NTSTATUS nt_status;
 109         struct auth_serversupplied_info *server_info;
 110         struct hdb_ldb_private *private = talloc_get_type(client->ctx, struct hdb_ldb_private);
 111         TALLOC_CTX *mem_ctx = talloc_named(private, 0, "samba_get_pac context");
 112         unsigned int userAccountControl;
 113
 114         if (!mem_ctx) {
 115                 return ENOMEM;
 116         }
 117
 118         /* The user account may be set not to want the PAC */
 119         userAccountControl = ldb_msg_find_attr_as_uint(private->msg, "userAccountControl", 0);
 120         if (userAccountControl & UF_NO_AUTH_DATA_REQUIRED) {
 121                 *pac = NULL;
 122                 return 0;
 123         }
 124
 125         nt_status = authsam_make_server_info(mem_ctx, private->samdb,
 126                                              private->msg,
 127                                              private->realm_ref_msg,
 128                                              data_blob(NULL, 0),
 129                                              data_blob(NULL, 0),
 130                                              &server_info);
 131         if (!NT_STATUS_IS_OK(nt_status)) {
 132                 DEBUG(0, ("Getting user info for PAC failed: %s\n",
 133                           nt_errstr(nt_status)));
 134                 return ENOMEM;
 135         }
 136
 137         ret = make_pac(context, mem_ctx, server_info, pac);
 138
 139         talloc_free(mem_ctx);
 140         return ret;
 141 }
 142
 143 /* Resign (and reform, including possibly new groups) a PAC */
 144
 145 krb5_error_code samba_kdc_reget_pac(void *priv, krb5_context context,
 146                                 const krb5_principal client_principal,
 147                                 struct hdb_entry_ex *client,
 148                                 struct hdb_entry_ex *server, krb5_pac *pac)
 149 {
 150         NTSTATUS nt_status;
 151         krb5_error_code ret;
 152
 153         unsigned int userAccountControl;
 154
 155         struct hdb_ldb_private *private = talloc_get_type(server->ctx, struct hdb_ldb_private);
 156         krb5_data k5pac_in;
 157         DATA_BLOB pac_in;
 158
 159         struct PAC_LOGON_INFO_CTR logon_info;
 160         union netr_Validation validation;
 161         struct auth_serversupplied_info *server_info_out;
 162
 163         TALLOC_CTX *mem_ctx = talloc_named(private, 0, "samba_get_pac context");
 164
 165         if (!mem_ctx) {
 166                 return ENOMEM;
 167         }
 168
 169         /* The service account may be set not to want the PAC */
 170         userAccountControl = ldb_msg_find_attr_as_uint(private->msg, "userAccountControl", 0);
 171         if (userAccountControl & UF_NO_AUTH_DATA_REQUIRED) {
 172                 *pac = NULL;
 173                 return 0;
 174         }
 175
 176         ret = krb5_pac_get_buffer(context, *pac, PAC_TYPE_LOGON_INFO, &k5pac_in);
 177         if (ret != 0) {
 178                 return ret;
 179         }
 180
 181         pac_in = data_blob_talloc(mem_ctx, k5pac_in.data, k5pac_in.length);
 182         krb5_data_free(&k5pac_in);
 183         if (!pac_in.data) {
 184                 talloc_free(mem_ctx);
 185                 return ENOMEM;
 186         }
 187
 188         nt_status = ndr_pull_struct_blob(&pac_in, mem_ctx, &logon_info,
 189                                       (ndr_pull_flags_fn_t)ndr_pull_PAC_LOGON_INFO_CTR);
 190         if (!NT_STATUS_IS_OK(nt_status) || !logon_info.info) {
 191                 talloc_free(mem_ctx);
 192                 DEBUG(0,("can't parse the PAC LOGON_INFO\n"));
 193                 return EINVAL;
 194         }
 195
 196         /* Pull this right into the normal auth sysstem structures */
 197         validation.sam3 = &logon_info.info->info3;
 198         nt_status = make_server_info_netlogon_validation(mem_ctx,
 199                                                          "",
 200                                                          3, &validation,
 201                                                          &server_info_out);
 202         if (!NT_STATUS_IS_OK(nt_status)) {
 203                 talloc_free(mem_ctx);
 204                 return ENOMEM;
 205         }
 206
 207         /* We will compleatly regenerate this pac */
 208         krb5_pac_free(context, *pac);
 209
 210         ret = make_pac(context, mem_ctx, server_info_out, pac);
 211
 212         talloc_free(mem_ctx);
 213         return ret;
 214 }
 215
 216 /* Given an hdb entry (and in particular it's private member), consult
 217  * the account_ok routine in auth/auth_sam.c for consistancy */
 218
 219
 220 krb5_error_code samba_kdc_check_client_access(void *priv,
 221                                               krb5_context context, hdb_entry_ex *entry_ex,
 222                                               KDC_REQ *req)
 223 {
 224         krb5_error_code ret;
 225         NTSTATUS nt_status;
 226         TALLOC_CTX *tmp_ctx = talloc_new(entry_ex->ctx);
 227         struct hdb_ldb_private *private = talloc_get_type(entry_ex->ctx, struct hdb_ldb_private);
 228         char *name, *workstation = NULL;
 229         HostAddresses *addresses = req->req_body.addresses;
 230         int i;
 231
 232         if (!tmp_ctx) {
 233                 return ENOMEM;
 234         }
 235
 236         ret = krb5_unparse_name(context, entry_ex->entry.principal, &name);
 237         if (ret != 0) {
 238                 talloc_free(tmp_ctx);
 239                 return ret;
 240         }
 241
 242         if (addresses) {
 243                 for (i=0; i < addresses->len; i++) {
 244                         if (addresses->val->addr_type == KRB5_ADDRESS_NETBIOS) {
 245                                 workstation = talloc_strndup(tmp_ctx, addresses->val->address.data, MIN(addresses->val->address.length, 15));
 246                                 if (workstation) {
 247                                         break;
 248                                 }
 249                         }
 250                 }
 251         }
 252
 253         /* Strip space padding */
 254         if (workstation) {
 255                 i = MIN(strlen(workstation), 15);
 256                 for (; i > 0 && workstation[i - 1] == ' '; i--) {
 257                         workstation[i - 1] = '\0';
 258                 }
 259         }
 260
 261         nt_status = authsam_account_ok(tmp_ctx,
 262                                        private->samdb,
 263                                        MSV1_0_ALLOW_SERVER_TRUST_ACCOUNT | MSV1_0_ALLOW_WORKSTATION_TRUST_ACCOUNT,
 264                                        private->msg,
 265                                        private->realm_ref_msg,
 266                                        workstation,
 267                                        name);
 268         free(name);
 269
 270         /* TODO:  Need a more complete mapping of NTSTATUS to krb5kdc errors */
 271
 272         if (!NT_STATUS_IS_OK(nt_status)) {
 273                 return KRB5KDC_ERR_POLICY;
 274         }
 275         return 0;
 276 }
 277