source3/auth/auth_generic.c

   1 /*
   2    Unix SMB/Netbios implementation.
   3    Version 3.0
   4    handle GENSEC authentication, server side
   5
   6    Copyright (C) Andrew Tridgell      2001
   7    Copyright (C) Andrew Bartlett 2001-2003,2011
   8    Copyright (C) Simo Sorce 2010.
   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.h"
  26 #include "../lib/tsocket/tsocket.h"
  27 #include "auth/gensec/gensec.h"
  28 #include "lib/param/param.h"
  29 #ifdef HAVE_KRB5
  30 #include "auth/kerberos/pac_utils.h"
  31 #endif
  32 #include "librpc/crypto/gse.h"
  33 #include "auth/credentials/credentials.h"
  34 #include "lib/param/loadparm.h"
  35
  36 static NTSTATUS auth3_generate_session_info_pac(struct auth4_context *auth_ctx,
  37                                                 TALLOC_CTX *mem_ctx,
  38                                                 struct smb_krb5_context *smb_krb5_context,
  39                                                 DATA_BLOB *pac_blob,
  40                                                 const char *princ_name,
  41                                                 const struct tsocket_address *remote_address,
  42                                                 uint32_t session_info_flags,
  43                                                 struct auth_session_info **session_info)
  44 {
  45         TALLOC_CTX *tmp_ctx;
  46         struct PAC_LOGON_INFO *logon_info = NULL;
  47         struct netr_SamInfo3 *info3_copy = NULL;
  48         bool is_mapped;
  49         bool is_guest;
  50         char *ntuser;
  51         char *ntdomain;
  52         char *username;
  53         char *rhost;
  54         struct passwd *pw;
  55         NTSTATUS status;
  56         int rc;
  57
  58         tmp_ctx = talloc_new(mem_ctx);
  59         if (!tmp_ctx) {
  60                 return NT_STATUS_NO_MEMORY;
  61         }
  62
  63         if (pac_blob) {
  64 #ifdef HAVE_KRB5
  65                 status = kerberos_pac_logon_info(tmp_ctx, *pac_blob, NULL, NULL,
  66                                                  NULL, NULL, 0, &logon_info);
  67 #else
  68                 status = NT_STATUS_ACCESS_DENIED;
  69 #endif
  70                 if (!NT_STATUS_IS_OK(status)) {
  71                         goto done;
  72                 }
  73         }
  74
  75         rc = get_remote_hostname(remote_address,
  76                                  &rhost,
  77                                  tmp_ctx);
  78         if (rc < 0) {
  79                 status = NT_STATUS_NO_MEMORY;
  80                 goto done;
  81         }
  82         if (strequal(rhost, "UNKNOWN")) {
  83                 rhost = tsocket_address_inet_addr_string(remote_address,
  84                                                          tmp_ctx);
  85                 if (rhost == NULL) {
  86                         status = NT_STATUS_NO_MEMORY;
  87                         goto done;
  88                 }
  89         }
  90
  91         status = get_user_from_kerberos_info(tmp_ctx, rhost,
  92                                              princ_name, logon_info,
  93                                              &is_mapped, &is_guest,
  94                                              &ntuser, &ntdomain,
  95                                              &username, &pw);
  96         if (!NT_STATUS_IS_OK(status)) {
  97                 DEBUG(1, ("Failed to map kerberos principal to system user "
  98                           "(%s)\n", nt_errstr(status)));
  99                 status = NT_STATUS_ACCESS_DENIED;
 100                 goto done;
 101         }
 102
 103         /* save the PAC data if we have it */
 104         if (logon_info) {
 105                 status = create_info3_from_pac_logon_info(tmp_ctx,
 106                                         logon_info,
 107                                         &info3_copy);
 108                 if (!NT_STATUS_IS_OK(status)) {
 109                         goto done;
 110                 }
 111                 netsamlogon_cache_store(ntuser, info3_copy);
 112         }
 113
 114         /* setup the string used by %U */
 115         sub_set_smb_name(username);
 116
 117         /* reload services so that the new %U is taken into account */
 118         lp_load(get_dyn_CONFIGFILE(), false, false, true, true);
 119
 120         status = make_session_info_krb5(mem_ctx,
 121                                         ntuser, ntdomain, username, pw,
 122                                         info3_copy, is_guest, is_mapped, NULL /* No session key for now, caller will sort it out */,
 123                                         session_info);
 124         if (!NT_STATUS_IS_OK(status)) {
 125                 DEBUG(1, ("Failed to map kerberos pac to server info (%s)\n",
 126                           nt_errstr(status)));
 127                 status = NT_STATUS_ACCESS_DENIED;
 128                 goto done;
 129         }
 130
 131         DEBUG(5, (__location__ "OK: user: %s domain: %s client: %s\n",
 132                   ntuser, ntdomain, rhost));
 133
 134         status = NT_STATUS_OK;
 135
 136 done:
 137         TALLOC_FREE(tmp_ctx);
 138         return status;
 139 }
 140
 141 static struct auth4_context *make_auth4_context_s3(TALLOC_CTX *mem_ctx, struct auth_context *auth_context)
 142 {
 143         struct auth4_context *auth4_context = talloc_zero(mem_ctx, struct auth4_context);
 144         if (auth4_context == NULL) {
 145                 DEBUG(10, ("failed to allocate auth4_context failed\n"));
 146                 return NULL;
 147         }
 148         auth4_context->generate_session_info_pac = auth3_generate_session_info_pac;
 149         auth4_context->generate_session_info = auth3_generate_session_info;
 150         auth4_context->get_ntlm_challenge = auth3_get_challenge;
 151         auth4_context->set_ntlm_challenge = auth3_set_challenge;
 152         auth4_context->check_ntlm_password = auth3_check_password;
 153         auth4_context->private_data = talloc_steal(auth4_context, auth_context);
 154         return auth4_context;
 155 }
 156
 157 NTSTATUS make_auth4_context(TALLOC_CTX *mem_ctx, struct auth4_context **auth4_context_out)
 158 {
 159         struct auth_context *auth_context;
 160         NTSTATUS nt_status;
 161
 162         TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
 163         NT_STATUS_HAVE_NO_MEMORY(tmp_ctx);
 164
 165         nt_status = make_auth_context_subsystem(tmp_ctx, &auth_context);
 166         if (!NT_STATUS_IS_OK(nt_status)) {
 167                 TALLOC_FREE(tmp_ctx);
 168                 return nt_status;
 169         }
 170
 171         if (auth_context->make_auth4_context) {
 172                 nt_status = auth_context->make_auth4_context(mem_ctx, auth4_context_out);
 173                 TALLOC_FREE(tmp_ctx);
 174                 return nt_status;
 175
 176         } else {
 177                 struct auth4_context *auth4_context = make_auth4_context_s3(tmp_ctx, auth_context);
 178                 if (auth4_context == NULL) {
 179                         TALLOC_FREE(tmp_ctx);
 180                         return NT_STATUS_NO_MEMORY;
 181                 }
 182                 *auth4_context_out = talloc_steal(mem_ctx, auth4_context);
 183                 TALLOC_FREE(tmp_ctx);
 184                 return NT_STATUS_OK;
 185         }
 186 }
 187
 188 NTSTATUS auth_generic_prepare(TALLOC_CTX *mem_ctx,
 189                               const struct tsocket_address *remote_address,
 190                               struct gensec_security **gensec_security_out)
 191 {
 192         struct gensec_security *gensec_security;
 193         struct auth_context *auth_context;
 194         NTSTATUS nt_status;
 195
 196         TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
 197         NT_STATUS_HAVE_NO_MEMORY(tmp_ctx);
 198
 199         nt_status = make_auth_context_subsystem(tmp_ctx, &auth_context);
 200         if (!NT_STATUS_IS_OK(nt_status)) {
 201                 TALLOC_FREE(tmp_ctx);
 202                 return nt_status;
 203         }
 204
 205         if (auth_context->prepare_gensec) {
 206                 nt_status = auth_context->prepare_gensec(tmp_ctx,
 207                                                          &gensec_security);
 208                 if (!NT_STATUS_IS_OK(nt_status)) {
 209                         TALLOC_FREE(tmp_ctx);
 210                         return nt_status;
 211                 }
 212         } else {
 213                 struct gensec_settings *gensec_settings;
 214                 struct loadparm_context *lp_ctx;
 215                 size_t idx = 0;
 216                 struct cli_credentials *server_credentials;
 217                 const char *dns_name;
 218                 const char *dns_domain;
 219                 struct auth4_context *auth4_context = make_auth4_context_s3(tmp_ctx, auth_context);
 220                 if (auth4_context == NULL) {
 221                         TALLOC_FREE(tmp_ctx);
 222                         return NT_STATUS_NO_MEMORY;
 223                 }
 224
 225                 lp_ctx = loadparm_init_s3(tmp_ctx, loadparm_s3_helpers());
 226                 if (lp_ctx == NULL) {
 227                         DEBUG(10, ("loadparm_init_s3 failed\n"));
 228                         TALLOC_FREE(tmp_ctx);
 229                         return NT_STATUS_INVALID_SERVER_STATE;
 230                 }
 231
 232                 gensec_settings = lpcfg_gensec_settings(tmp_ctx, lp_ctx);
 233                 if (lp_ctx == NULL) {
 234                         DEBUG(10, ("lpcfg_gensec_settings failed\n"));
 235                         TALLOC_FREE(tmp_ctx);
 236                         return NT_STATUS_NO_MEMORY;
 237                 }
 238
 239                 /*
 240                  * This should be a 'netbios domain -> DNS domain'
 241                  * mapping, and can currently validly return NULL on
 242                  * poorly configured systems.
 243                  *
 244                  * This is used for the NTLMSSP server
 245                  *
 246                  */
 247                 dns_name = get_mydnsfullname();
 248                 if (dns_name == NULL) {
 249                         dns_name = "";
 250                 }
 251
 252                 dns_domain = get_mydnsdomname(tmp_ctx);
 253                 if (dns_domain == NULL) {
 254                         dns_domain = "";
 255                 }
 256
 257                 gensec_settings->server_dns_name = strlower_talloc(gensec_settings, dns_name);
 258                 if (gensec_settings->server_dns_name == NULL) {
 259                         TALLOC_FREE(tmp_ctx);
 260                         return NT_STATUS_NO_MEMORY;
 261                 }
 262
 263                 gensec_settings->server_dns_domain = strlower_talloc(gensec_settings, dns_domain);
 264                 if (gensec_settings->server_dns_domain == NULL) {
 265                         TALLOC_FREE(tmp_ctx);
 266                         return NT_STATUS_NO_MEMORY;
 267                 }
 268
 269                 gensec_settings->backends = talloc_zero_array(gensec_settings,
 270                                                 struct gensec_security_ops *, 4);
 271                 if (gensec_settings->backends == NULL) {
 272                         TALLOC_FREE(tmp_ctx);
 273                         return NT_STATUS_NO_MEMORY;
 274                 }
 275
 276                 gensec_init();
 277
 278                 /* These need to be in priority order, krb5 before NTLMSSP */
 279 #if defined(HAVE_KRB5)
 280                 gensec_settings->backends[idx++] = &gensec_gse_krb5_security_ops;
 281 #endif
 282
 283                 gensec_settings->backends[idx++] = gensec_security_by_oid(NULL, GENSEC_OID_NTLMSSP);
 284
 285                 gensec_settings->backends[idx++] = gensec_security_by_oid(NULL,
 286                                                         GENSEC_OID_SPNEGO);
 287
 288                 /*
 289                  * This is anonymous for now, because we just use it
 290                  * to set the kerberos state at the moment
 291                  */
 292                 server_credentials = cli_credentials_init_anon(tmp_ctx);
 293                 if (!server_credentials) {
 294                         DEBUG(0, ("auth_generic_prepare: Failed to init server credentials\n"));
 295                         return NT_STATUS_NO_MEMORY;
 296                 }
 297
 298                 cli_credentials_set_conf(server_credentials, lp_ctx);
 299
 300                 if (lp_security() == SEC_ADS || USE_KERBEROS_KEYTAB) {
 301                         cli_credentials_set_kerberos_state(server_credentials, CRED_AUTO_USE_KERBEROS);
 302                 } else {
 303                         cli_credentials_set_kerberos_state(server_credentials, CRED_DONT_USE_KERBEROS);
 304                 }
 305
 306                 nt_status = gensec_server_start(tmp_ctx, gensec_settings,
 307                                                 auth4_context, &gensec_security);
 308
 309                 if (!NT_STATUS_IS_OK(nt_status)) {
 310                         TALLOC_FREE(tmp_ctx);
 311                         return nt_status;
 312                 }
 313
 314                 gensec_set_credentials(gensec_security, server_credentials);
 315
 316                 talloc_unlink(tmp_ctx, lp_ctx);
 317                 talloc_unlink(tmp_ctx, server_credentials);
 318                 talloc_unlink(tmp_ctx, gensec_settings);
 319                 talloc_unlink(tmp_ctx, auth4_context);
 320         }
 321
 322         nt_status = gensec_set_remote_address(gensec_security,
 323                                               remote_address);
 324         if (!NT_STATUS_IS_OK(nt_status)) {
 325                 TALLOC_FREE(tmp_ctx);
 326                 return nt_status;
 327         }
 328
 329         *gensec_security_out = talloc_steal(mem_ctx, gensec_security);
 330         TALLOC_FREE(tmp_ctx);
 331         return NT_STATUS_OK;
 332 }
 333
 334 NTSTATUS auth_check_password_session_info(struct auth4_context *auth_context,
 335                                           TALLOC_CTX *mem_ctx,
 336                                           struct auth_usersupplied_info *user_info,
 337                                           struct auth_session_info **session_info)
 338 {
 339         NTSTATUS nt_status;
 340         void *server_info;
 341
 342         nt_status = auth_context->check_ntlm_password(auth_context,
 343                                                       talloc_tos(),
 344                                                       user_info,
 345                                                       &server_info, NULL, NULL);
 346
 347         if (NT_STATUS_IS_OK(nt_status)) {
 348                 nt_status = auth_context->generate_session_info(auth_context,
 349                                                                 mem_ctx,
 350                                                                 server_info,
 351                                                                 user_info->client.account_name,
 352                                                                 AUTH_SESSION_INFO_UNIX_TOKEN |
 353                                                                 AUTH_SESSION_INFO_DEFAULT_GROUPS,
 354                                                                 session_info);
 355                 TALLOC_FREE(server_info);
 356         }
 357         return nt_status;
 358 }