source4/auth/session.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Authentication utility functions
   4    Copyright (C) Andrew Tridgell 1992-1998
   5    Copyright (C) Andrew Bartlett 2001-2010
   6    Copyright (C) Jeremy Allison 2000-2001
   7    Copyright (C) Rafal Szczesniak 2002
   8    Copyright (C) Stefan Metzmacher 2005
   9
  10    This program is free software; you can redistribute it and/or modify
  11    it under the terms of the GNU General Public License as published by
  12    the Free Software Foundation; either version 3 of the License, or
  13    (at your option) any later version.
  14
  15    This program is distributed in the hope that it will be useful,
  16    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18    GNU General Public License for more details.
  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 "auth/auth.h"
  26 #include "libcli/security/security.h"
  27 #include "libcli/auth/libcli_auth.h"
  28 #include "dsdb/samdb/samdb.h"
  29 #include "auth/session_proto.h"
  30
  31 _PUBLIC_ struct auth_session_info *anonymous_session(TALLOC_CTX *mem_ctx,
  32                                             struct loadparm_context *lp_ctx)
  33 {
  34         NTSTATUS nt_status;
  35         struct auth_session_info *session_info = NULL;
  36         nt_status = auth_anonymous_session_info(mem_ctx, lp_ctx, &session_info);
  37         if (!NT_STATUS_IS_OK(nt_status)) {
  38                 return NULL;
  39         }
  40         return session_info;
  41 }
  42
  43 _PUBLIC_ NTSTATUS auth_generate_session_info(TALLOC_CTX *mem_ctx,
  44                                              struct auth_context *auth_context, /* Optional if the domain SID is in the NT AUTHORITY domain */
  45                                              struct auth_serversupplied_info *server_info,
  46                                              uint32_t session_info_flags,
  47                                              struct auth_session_info **_session_info)
  48 {
  49         struct auth_session_info *session_info;
  50         NTSTATUS nt_status;
  51         unsigned int i, num_groupSIDs = 0;
  52         const char *account_sid_string;
  53         const char *account_sid_dn;
  54         DATA_BLOB account_sid_blob;
  55         const char *primary_group_string;
  56         const char *primary_group_dn;
  57         DATA_BLOB primary_group_blob;
  58
  59         const char *filter;
  60
  61         struct dom_sid **groupSIDs = NULL;
  62         const struct dom_sid *dom_sid, *anonymous_sid, *system_sid;
  63
  64         TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
  65         NT_STATUS_HAVE_NO_MEMORY(tmp_ctx);
  66
  67         /* For now, we don't have trusted domains, so we do a very
  68          * simple check to see that the user's SID is in *this*
  69          * domain, and then trust the user account control.  When we
  70          * get trusted domains, we should check it's a trusted domain
  71          * in this forest.  This elaborate check is to try and avoid a
  72          * nasty security bug if we forget about this later... */
  73
  74         session_info = talloc(tmp_ctx, struct auth_session_info);
  75         NT_STATUS_HAVE_NO_MEMORY_AND_FREE(session_info, tmp_ctx);
  76
  77         session_info->server_info = talloc_reference(session_info, server_info);
  78
  79         /* unless set otherwise, the session key is the user session
  80          * key from the auth subsystem */
  81         session_info->session_key = server_info->user_session_key;
  82
  83         anonymous_sid = dom_sid_parse_talloc(tmp_ctx, SID_NT_ANONYMOUS);
  84         NT_STATUS_HAVE_NO_MEMORY_AND_FREE(anonymous_sid, tmp_ctx);
  85
  86         system_sid = dom_sid_parse_talloc(tmp_ctx, SID_NT_SYSTEM);
  87         NT_STATUS_HAVE_NO_MEMORY_AND_FREE(system_sid, tmp_ctx);
  88
  89         if (dom_sid_equal(anonymous_sid, server_info->account_sid)) {
  90                 /* Don't expand nested groups of system, anonymous etc*/
  91         } else if (dom_sid_equal(system_sid, server_info->account_sid)) {
  92                 /* Don't expand nested groups of system, anonymous etc*/
  93         } else if (auth_context) {
  94                 if (server_info->acct_flags & ACB_SVRTRUST) {
  95                         dom_sid = samdb_domain_sid(auth_context->sam_ctx);
  96                         if (dom_sid) {
  97                                 if (dom_sid_in_domain(dom_sid, server_info->account_sid)) {
  98                                 session_info_flags |= AUTH_SESSION_INFO_ENTERPRISE_DC;
  99                                 } else {
 100                                         DEBUG(2, ("DC %s is not in our domain.  "
 101                                                   "It will not have Enterprise Domain Controllers membership on this server",
 102                                                   server_info->account_name));
 103                                 }
 104                         } else {
 105                                 DEBUG(2, ("Could not obtain local domain SID, "
 106                                           "so can not determine if DC %s is a DC of this domain.  "
 107                                           "It will not have Enterprise Domain Controllers membership",
 108                                           server_info->account_name));
 109                         }
 110                 }
 111
 112                 groupSIDs = talloc_array(tmp_ctx, struct dom_sid *, server_info->n_domain_groups);
 113                 NT_STATUS_HAVE_NO_MEMORY_AND_FREE(groupSIDs, tmp_ctx);
 114                 if (!groupSIDs) {
 115                         talloc_free(tmp_ctx);
 116                         return NT_STATUS_NO_MEMORY;
 117                 }
 118
 119                 num_groupSIDs = server_info->n_domain_groups;
 120
 121                 for (i=0; i < server_info->n_domain_groups; i++) {
 122                         groupSIDs[i] = server_info->domain_groups[i];
 123                 }
 124
 125                 filter = talloc_asprintf(tmp_ctx, "(&(objectClass=group)(groupType:1.2.840.113556.1.4.803:=%u))",
 126                                          GROUP_TYPE_BUILTIN_LOCAL_GROUP);
 127
 128                 /* Search for each group in the token */
 129
 130                 /* Expands the account SID - this function takes in
 131                  * memberOf-like values, so we fake one up with the
 132                  * <SID=S-...> format of DN and then let it expand
 133                  * them, as long as they meet the filter - so only
 134                  * builtin groups
 135                  *
 136                  * We already have the primary group in the token, so set
 137                  * 'only childs' flag to true
 138                  */
 139                 account_sid_string = dom_sid_string(tmp_ctx, server_info->account_sid);
 140                 NT_STATUS_HAVE_NO_MEMORY_AND_FREE(account_sid_string, server_info);
 141
 142                 account_sid_dn = talloc_asprintf(tmp_ctx, "<SID=%s>", account_sid_string);
 143                 NT_STATUS_HAVE_NO_MEMORY_AND_FREE(account_sid_dn, server_info);
 144
 145                 account_sid_blob = data_blob_string_const(account_sid_dn);
 146
 147                 nt_status = authsam_expand_nested_groups(auth_context->sam_ctx, &account_sid_blob, true, filter,
 148                                                          tmp_ctx, &groupSIDs, &num_groupSIDs);
 149                 if (!NT_STATUS_IS_OK(nt_status)) {
 150                         talloc_free(tmp_ctx);
 151                         return nt_status;
 152                 }
 153
 154                 /* Expands the primary group - this function takes in
 155                  * memberOf-like values, so we fake one up with the
 156                  * <SID=S-...> format of DN and then let it expand
 157                  * them, as long as they meet the filter - so only
 158                  * builtin groups
 159                  *
 160                  * We already have the primary group in the token, so set
 161                  * 'only childs' flag to true
 162                  */
 163                 primary_group_string = dom_sid_string(tmp_ctx, server_info->primary_group_sid);
 164                 NT_STATUS_HAVE_NO_MEMORY_AND_FREE(primary_group_string, server_info);
 165
 166                 primary_group_dn = talloc_asprintf(tmp_ctx, "<SID=%s>", primary_group_string);
 167                 NT_STATUS_HAVE_NO_MEMORY_AND_FREE(primary_group_dn, server_info);
 168
 169                 primary_group_blob = data_blob_string_const(primary_group_dn);
 170
 171                 nt_status = authsam_expand_nested_groups(auth_context->sam_ctx, &primary_group_blob, true, filter,
 172                                                          tmp_ctx, &groupSIDs, &num_groupSIDs);
 173                 if (!NT_STATUS_IS_OK(nt_status)) {
 174                         talloc_free(tmp_ctx);
 175                         return nt_status;
 176                 }
 177
 178                 for (i = 0; i < server_info->n_domain_groups; i++) {
 179                         char *group_string;
 180                         const char *group_dn;
 181                         DATA_BLOB group_blob;
 182
 183                         group_string = dom_sid_string(tmp_ctx,
 184                                                       server_info->domain_groups[i]);
 185                         NT_STATUS_HAVE_NO_MEMORY_AND_FREE(group_string, server_info);
 186
 187                         group_dn = talloc_asprintf(tmp_ctx, "<SID=%s>", group_string);
 188                         talloc_free(group_string);
 189                         NT_STATUS_HAVE_NO_MEMORY_AND_FREE(group_dn, server_info);
 190                         group_blob = data_blob_string_const(group_dn);
 191
 192                         /* This function takes in memberOf values and expands
 193                          * them, as long as they meet the filter - so only
 194                          * builtin groups */
 195                         nt_status = authsam_expand_nested_groups(auth_context->sam_ctx, &group_blob, true, filter,
 196                                                                  tmp_ctx, &groupSIDs, &num_groupSIDs);
 197                         if (!NT_STATUS_IS_OK(nt_status)) {
 198                                 talloc_free(tmp_ctx);
 199                                 return nt_status;
 200                         }
 201                 }
 202         }
 203
 204         nt_status = security_token_create(session_info,
 205                                           auth_context ? auth_context->event_ctx : NULL,
 206                                           auth_context ? auth_context->lp_ctx : NULL,
 207                                           server_info->account_sid,
 208                                           server_info->primary_group_sid,
 209                                           num_groupSIDs,
 210                                           groupSIDs,
 211                                           session_info_flags,
 212                                           &session_info->security_token);
 213         NT_STATUS_NOT_OK_RETURN_AND_FREE(nt_status, tmp_ctx);
 214
 215         session_info->credentials = NULL;
 216
 217         talloc_steal(mem_ctx, session_info);
 218         *_session_info = session_info;
 219         talloc_free(tmp_ctx);
 220         return NT_STATUS_OK;
 221 }
 222
 223 /**
 224  * prints a struct auth_session_info security token to debug output.
 225  */
 226 void auth_session_info_debug(int dbg_lev,
 227                              const struct auth_session_info *session_info)
 228 {
 229         if (!session_info) {
 230                 DEBUG(dbg_lev, ("Session Info: (NULL)\n"));
 231                 return;
 232         }
 233
 234         security_token_debug(dbg_lev, session_info->security_token);
 235 }
 236