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 #include "librpc/gen_ndr/dcerpc.h"
  36
  37 static NTSTATUS auth3_generate_session_info_pac(struct auth4_context *auth_ctx,
  38                                                 TALLOC_CTX *mem_ctx,
  39                                                 struct smb_krb5_context *smb_krb5_context,
  40                                                 DATA_BLOB *pac_blob,
  41                                                 const char *princ_name,
  42                                                 const struct tsocket_address *remote_address,
  43                                                 uint32_t session_info_flags,
  44                                                 struct auth_session_info **session_info)
  45 {
  46         TALLOC_CTX *tmp_ctx;
  47         struct PAC_LOGON_INFO *logon_info = 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                 netsamlogon_cache_store(ntuser, &logon_info->info3);
 106         }
 107
 108         /* setup the string used by %U */
 109         sub_set_smb_name(username);
 110
 111         /* reload services so that the new %U is taken into account */
 112         lp_load(get_dyn_CONFIGFILE(), false, false, true, true);
 113
 114         status = make_session_info_krb5(mem_ctx,
 115                                         ntuser, ntdomain, username, pw,
 116                                         logon_info, is_guest, is_mapped, NULL /* No session key for now, caller will sort it out */,
 117                                         session_info);
 118         if (!NT_STATUS_IS_OK(status)) {
 119                 DEBUG(1, ("Failed to map kerberos pac to server info (%s)\n",
 120                           nt_errstr(status)));
 121                 status = NT_STATUS_ACCESS_DENIED;
 122                 goto done;
 123         }
 124
 125         DEBUG(5, (__location__ "OK: user: %s domain: %s client: %s\n",
 126                   ntuser, ntdomain, rhost));
 127
 128         status = NT_STATUS_OK;
 129
 130 done:
 131         TALLOC_FREE(tmp_ctx);
 132         return status;
 133 }
 134
 135 static struct auth4_context *make_auth4_context_s3(TALLOC_CTX *mem_ctx, struct auth_context *auth_context)
 136 {
 137         struct auth4_context *auth4_context = talloc_zero(mem_ctx, struct auth4_context);
 138         if (auth4_context == NULL) {
 139                 DEBUG(10, ("failed to allocate auth4_context failed\n"));
 140                 return NULL;
 141         }
 142         auth4_context->generate_session_info_pac = auth3_generate_session_info_pac;
 143         auth4_context->generate_session_info = auth3_generate_session_info;
 144         auth4_context->get_ntlm_challenge = auth3_get_challenge;
 145         auth4_context->set_ntlm_challenge = auth3_set_challenge;
 146         auth4_context->check_ntlm_password = auth3_check_password;
 147         auth4_context->private_data = talloc_steal(auth4_context, auth_context);
 148         return auth4_context;
 149 }
 150
 151 NTSTATUS make_auth4_context(TALLOC_CTX *mem_ctx, struct auth4_context **auth4_context_out)
 152 {
 153         struct auth_context *auth_context;
 154         NTSTATUS nt_status;
 155
 156         TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
 157         NT_STATUS_HAVE_NO_MEMORY(tmp_ctx);
 158
 159         nt_status = make_auth_context_subsystem(tmp_ctx, &auth_context);
 160         if (!NT_STATUS_IS_OK(nt_status)) {
 161                 TALLOC_FREE(tmp_ctx);
 162                 return nt_status;
 163         }
 164
 165         if (auth_context->make_auth4_context) {
 166                 nt_status = auth_context->make_auth4_context(mem_ctx, auth4_context_out);
 167                 TALLOC_FREE(tmp_ctx);
 168                 return nt_status;
 169
 170         } else {
 171                 struct auth4_context *auth4_context = make_auth4_context_s3(tmp_ctx, auth_context);
 172                 if (auth4_context == NULL) {
 173                         TALLOC_FREE(tmp_ctx);
 174                         return NT_STATUS_NO_MEMORY;
 175                 }
 176                 *auth4_context_out = talloc_steal(mem_ctx, auth4_context);
 177                 TALLOC_FREE(tmp_ctx);
 178                 return NT_STATUS_OK;
 179         }
 180 }
 181
 182 NTSTATUS auth_generic_prepare(TALLOC_CTX *mem_ctx,
 183                               const struct tsocket_address *remote_address,
 184                               struct gensec_security **gensec_security_out)
 185 {
 186         struct gensec_security *gensec_security;
 187         struct auth_context *auth_context;
 188         NTSTATUS nt_status;
 189
 190         TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
 191         NT_STATUS_HAVE_NO_MEMORY(tmp_ctx);
 192
 193         nt_status = make_auth_context_subsystem(tmp_ctx, &auth_context);
 194         if (!NT_STATUS_IS_OK(nt_status)) {
 195                 TALLOC_FREE(tmp_ctx);
 196                 return nt_status;
 197         }
 198
 199         if (auth_context->prepare_gensec) {
 200                 nt_status = auth_context->prepare_gensec(tmp_ctx,
 201                                                          &gensec_security);
 202                 if (!NT_STATUS_IS_OK(nt_status)) {
 203                         TALLOC_FREE(tmp_ctx);
 204                         return nt_status;
 205                 }
 206         } else {
 207                 const struct gensec_security_ops **backends = NULL;
 208                 struct gensec_settings *gensec_settings;
 209                 struct loadparm_context *lp_ctx;
 210                 size_t idx = 0;
 211                 struct cli_credentials *server_credentials;
 212                 const char *dns_name;
 213                 const char *dns_domain;
 214                 struct auth4_context *auth4_context = make_auth4_context_s3(tmp_ctx, auth_context);
 215                 if (auth4_context == NULL) {
 216                         TALLOC_FREE(tmp_ctx);
 217                         return NT_STATUS_NO_MEMORY;
 218                 }
 219
 220                 lp_ctx = loadparm_init_s3(tmp_ctx, loadparm_s3_helpers());
 221                 if (lp_ctx == NULL) {
 222                         DEBUG(10, ("loadparm_init_s3 failed\n"));
 223                         TALLOC_FREE(tmp_ctx);
 224                         return NT_STATUS_INVALID_SERVER_STATE;
 225                 }
 226
 227                 gensec_settings = lpcfg_gensec_settings(tmp_ctx, lp_ctx);
 228                 if (lp_ctx == NULL) {
 229                         DEBUG(10, ("lpcfg_gensec_settings failed\n"));
 230                         TALLOC_FREE(tmp_ctx);
 231                         return NT_STATUS_NO_MEMORY;
 232                 }
 233
 234                 /*
 235                  * This should be a 'netbios domain -> DNS domain'
 236                  * mapping, and can currently validly return NULL on
 237                  * poorly configured systems.
 238                  *
 239                  * This is used for the NTLMSSP server
 240                  *
 241                  */
 242                 dns_name = get_mydnsfullname();
 243                 if (dns_name == NULL) {
 244                         dns_name = "";
 245                 }
 246
 247                 dns_domain = get_mydnsdomname(tmp_ctx);
 248                 if (dns_domain == NULL) {
 249                         dns_domain = "";
 250                 }
 251
 252                 gensec_settings->server_dns_name = strlower_talloc(gensec_settings, dns_name);
 253                 if (gensec_settings->server_dns_name == NULL) {
 254                         TALLOC_FREE(tmp_ctx);
 255                         return NT_STATUS_NO_MEMORY;
 256                 }
 257
 258                 gensec_settings->server_dns_domain = strlower_talloc(gensec_settings, dns_domain);
 259                 if (gensec_settings->server_dns_domain == NULL) {
 260                         TALLOC_FREE(tmp_ctx);
 261                         return NT_STATUS_NO_MEMORY;
 262                 }
 263
 264                 backends = talloc_zero_array(gensec_settings,
 265                                              const struct gensec_security_ops *, 5);
 266                 if (backends == NULL) {
 267                         TALLOC_FREE(tmp_ctx);
 268                         return NT_STATUS_NO_MEMORY;
 269                 }
 270                 gensec_settings->backends = backends;
 271
 272                 gensec_init();
 273
 274                 /* These need to be in priority order, krb5 before NTLMSSP */
 275 #if defined(HAVE_KRB5)
 276                 backends[idx++] = &gensec_gse_krb5_security_ops;
 277 #endif
 278
 279                 backends[idx++] = gensec_security_by_oid(NULL, GENSEC_OID_NTLMSSP);
 280
 281                 backends[idx++] = gensec_security_by_oid(NULL, GENSEC_OID_SPNEGO);
 282
 283                 backends[idx++] = gensec_security_by_auth_type(NULL, DCERPC_AUTH_TYPE_SCHANNEL);
 284
 285                 /*
 286                  * This is anonymous for now, because we just use it
 287                  * to set the kerberos state at the moment
 288                  */
 289                 server_credentials = cli_credentials_init_anon(tmp_ctx);
 290                 if (!server_credentials) {
 291                         DEBUG(0, ("auth_generic_prepare: Failed to init server credentials\n"));
 292                         return NT_STATUS_NO_MEMORY;
 293                 }
 294
 295                 cli_credentials_set_conf(server_credentials, lp_ctx);
 296
 297                 if (lp_security() == SEC_ADS || USE_KERBEROS_KEYTAB) {
 298                         cli_credentials_set_kerberos_state(server_credentials, CRED_AUTO_USE_KERBEROS);
 299                 } else {
 300                         cli_credentials_set_kerberos_state(server_credentials, CRED_DONT_USE_KERBEROS);
 301                 }
 302
 303                 nt_status = gensec_server_start(tmp_ctx, gensec_settings,
 304                                                 auth4_context, &gensec_security);
 305
 306                 if (!NT_STATUS_IS_OK(nt_status)) {
 307                         TALLOC_FREE(tmp_ctx);
 308                         return nt_status;
 309                 }
 310
 311                 gensec_set_credentials(gensec_security, server_credentials);
 312
 313                 talloc_unlink(tmp_ctx, lp_ctx);
 314                 talloc_unlink(tmp_ctx, server_credentials);
 315                 talloc_unlink(tmp_ctx, gensec_settings);
 316                 talloc_unlink(tmp_ctx, auth4_context);
 317         }
 318
 319         nt_status = gensec_set_remote_address(gensec_security,
 320                                               remote_address);
 321         if (!NT_STATUS_IS_OK(nt_status)) {
 322                 TALLOC_FREE(tmp_ctx);
 323                 return nt_status;
 324         }
 325
 326         *gensec_security_out = talloc_steal(mem_ctx, gensec_security);
 327         TALLOC_FREE(tmp_ctx);
 328         return NT_STATUS_OK;
 329 }
 330
 331 NTSTATUS auth_check_password_session_info(struct auth4_context *auth_context,
 332                                           TALLOC_CTX *mem_ctx,
 333                                           struct auth_usersupplied_info *user_info,
 334                                           struct auth_session_info **session_info)
 335 {
 336         NTSTATUS nt_status;
 337         void *server_info;
 338
 339         nt_status = auth_context->check_ntlm_password(auth_context,
 340                                                       talloc_tos(),
 341                                                       user_info,
 342                                                       &server_info, NULL, NULL);
 343
 344         if (NT_STATUS_IS_OK(nt_status)) {
 345                 nt_status = auth_context->generate_session_info(auth_context,
 346                                                                 mem_ctx,
 347                                                                 server_info,
 348                                                                 user_info->client.account_name,
 349                                                                 AUTH_SESSION_INFO_UNIX_TOKEN |
 350                                                                 AUTH_SESSION_INFO_DEFAULT_GROUPS,
 351                                                                 session_info);
 352                 TALLOC_FREE(server_info);
 353         }
 354         return nt_status;
 355 }