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
  35 static NTSTATUS auth3_generate_session_info_pac(struct auth4_context *auth_ctx,
  36                                                 TALLOC_CTX *mem_ctx,
  37                                                 struct smb_krb5_context *smb_krb5_context,
  38                                                 DATA_BLOB *pac_blob,
  39                                                 const char *princ_name,
  40                                                 const struct tsocket_address *remote_address,
  41                                                 uint32_t session_info_flags,
  42                                                 struct auth_session_info **session_info)
  43 {
  44         TALLOC_CTX *tmp_ctx;
  45         struct PAC_LOGON_INFO *logon_info = NULL;
  46         bool is_mapped;
  47         bool is_guest;
  48         char *ntuser;
  49         char *ntdomain;
  50         char *username;
  51         char *rhost;
  52         struct passwd *pw;
  53         NTSTATUS status;
  54         int rc;
  55
  56         tmp_ctx = talloc_new(mem_ctx);
  57         if (!tmp_ctx) {
  58                 return NT_STATUS_NO_MEMORY;
  59         }
  60
  61         if (pac_blob) {
  62 #ifdef HAVE_KRB5
  63                 status = kerberos_pac_logon_info(tmp_ctx, *pac_blob, NULL, NULL,
  64                                                  NULL, NULL, 0, &logon_info);
  65 #else
  66                 status = NT_STATUS_ACCESS_DENIED;
  67 #endif
  68                 if (!NT_STATUS_IS_OK(status)) {
  69                         goto done;
  70                 }
  71         }
  72
  73         rc = get_remote_hostname(remote_address,
  74                                  &rhost,
  75                                  tmp_ctx);
  76         if (rc < 0) {
  77                 status = NT_STATUS_NO_MEMORY;
  78                 goto done;
  79         }
  80         if (strequal(rhost, "UNKNOWN")) {
  81                 rhost = tsocket_address_inet_addr_string(remote_address,
  82                                                          tmp_ctx);
  83                 if (rhost == NULL) {
  84                         status = NT_STATUS_NO_MEMORY;
  85                         goto done;
  86                 }
  87         }
  88
  89         status = get_user_from_kerberos_info(tmp_ctx, rhost,
  90                                              princ_name, logon_info,
  91                                              &is_mapped, &is_guest,
  92                                              &ntuser, &ntdomain,
  93                                              &username, &pw);
  94         if (!NT_STATUS_IS_OK(status)) {
  95                 DEBUG(1, ("Failed to map kerberos principal to system user "
  96                           "(%s)\n", nt_errstr(status)));
  97                 status = NT_STATUS_ACCESS_DENIED;
  98                 goto done;
  99         }
 100
 101         /* save the PAC data if we have it */
 102         if (logon_info) {
 103                 netsamlogon_cache_store(ntuser, &logon_info->info3);
 104         }
 105
 106         /* setup the string used by %U */
 107         sub_set_smb_name(username);
 108
 109         /* reload services so that the new %U is taken into account */
 110         lp_load(get_dyn_CONFIGFILE(), false, false, true, true);
 111
 112         status = make_session_info_krb5(mem_ctx,
 113                                         ntuser, ntdomain, username, pw,
 114                                         logon_info, is_guest, is_mapped, NULL /* No session key for now, caller will sort it out */,
 115                                         session_info);
 116         if (!NT_STATUS_IS_OK(status)) {
 117                 DEBUG(1, ("Failed to map kerberos pac to server info (%s)\n",
 118                           nt_errstr(status)));
 119                 status = NT_STATUS_ACCESS_DENIED;
 120                 goto done;
 121         }
 122
 123         DEBUG(5, (__location__ "OK: user: %s domain: %s client: %s\n",
 124                   ntuser, ntdomain, rhost));
 125
 126         status = NT_STATUS_OK;
 127
 128 done:
 129         TALLOC_FREE(tmp_ctx);
 130         return status;
 131 }
 132
 133 static struct auth4_context *make_auth4_context_s3(TALLOC_CTX *mem_ctx, struct auth_context *auth_context)
 134 {
 135         struct auth4_context *auth4_context = talloc_zero(mem_ctx, struct auth4_context);
 136         if (auth4_context == NULL) {
 137                 DEBUG(10, ("failed to allocate auth4_context failed\n"));
 138                 return NULL;
 139         }
 140         auth4_context->generate_session_info_pac = auth3_generate_session_info_pac;
 141         auth4_context->generate_session_info = auth3_generate_session_info;
 142         auth4_context->get_ntlm_challenge = auth3_get_challenge;
 143         auth4_context->set_ntlm_challenge = auth3_set_challenge;
 144         auth4_context->check_ntlm_password = auth3_check_password;
 145         auth4_context->private_data = talloc_steal(auth4_context, auth_context);
 146         return auth4_context;
 147 }
 148
 149 NTSTATUS make_auth4_context(TALLOC_CTX *mem_ctx, struct auth4_context **auth4_context_out)
 150 {
 151         struct auth_context *auth_context;
 152         NTSTATUS nt_status;
 153
 154         TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
 155         NT_STATUS_HAVE_NO_MEMORY(tmp_ctx);
 156
 157         nt_status = make_auth_context_subsystem(tmp_ctx, &auth_context);
 158         if (!NT_STATUS_IS_OK(nt_status)) {
 159                 TALLOC_FREE(tmp_ctx);
 160                 return nt_status;
 161         }
 162
 163         if (auth_context->make_auth4_context) {
 164                 nt_status = auth_context->make_auth4_context(mem_ctx, auth4_context_out);
 165                 TALLOC_FREE(tmp_ctx);
 166                 return nt_status;
 167
 168         } else {
 169                 struct auth4_context *auth4_context = make_auth4_context_s3(tmp_ctx, auth_context);
 170                 if (auth4_context == NULL) {
 171                         TALLOC_FREE(tmp_ctx);
 172                         return NT_STATUS_NO_MEMORY;
 173                 }
 174                 *auth4_context_out = talloc_steal(mem_ctx, auth4_context);
 175                 TALLOC_FREE(tmp_ctx);
 176                 return NT_STATUS_OK;
 177         }
 178 }
 179
 180 NTSTATUS auth_generic_prepare(TALLOC_CTX *mem_ctx,
 181                               const struct tsocket_address *remote_address,
 182                               struct gensec_security **gensec_security_out)
 183 {
 184         struct gensec_security *gensec_security;
 185         struct auth_context *auth_context;
 186         NTSTATUS nt_status;
 187
 188         TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
 189         NT_STATUS_HAVE_NO_MEMORY(tmp_ctx);
 190
 191         nt_status = make_auth_context_subsystem(tmp_ctx, &auth_context);
 192         if (!NT_STATUS_IS_OK(nt_status)) {
 193                 TALLOC_FREE(tmp_ctx);
 194                 return nt_status;
 195         }
 196
 197         if (auth_context->prepare_gensec) {
 198                 nt_status = auth_context->prepare_gensec(tmp_ctx,
 199                                                          &gensec_security);
 200                 if (!NT_STATUS_IS_OK(nt_status)) {
 201                         TALLOC_FREE(tmp_ctx);
 202                         return nt_status;
 203                 }
 204         } else {
 205                 struct gensec_settings *gensec_settings;
 206                 struct loadparm_context *lp_ctx;
 207                 size_t idx = 0;
 208                 struct cli_credentials *server_credentials;
 209                 const char *dns_name;
 210                 const char *dns_domain;
 211                 struct auth4_context *auth4_context = make_auth4_context_s3(tmp_ctx, auth_context);
 212                 if (auth4_context == NULL) {
 213                         TALLOC_FREE(tmp_ctx);
 214                         return NT_STATUS_NO_MEMORY;
 215                 }
 216
 217                 lp_ctx = loadparm_init_s3(tmp_ctx, loadparm_s3_helpers());
 218                 if (lp_ctx == NULL) {
 219                         DEBUG(10, ("loadparm_init_s3 failed\n"));
 220                         TALLOC_FREE(tmp_ctx);
 221                         return NT_STATUS_INVALID_SERVER_STATE;
 222                 }
 223
 224                 gensec_settings = lpcfg_gensec_settings(tmp_ctx, lp_ctx);
 225                 if (lp_ctx == NULL) {
 226                         DEBUG(10, ("lpcfg_gensec_settings failed\n"));
 227                         TALLOC_FREE(tmp_ctx);
 228                         return NT_STATUS_NO_MEMORY;
 229                 }
 230
 231                 /*
 232                  * This should be a 'netbios domain -> DNS domain'
 233                  * mapping, and can currently validly return NULL on
 234                  * poorly configured systems.
 235                  *
 236                  * This is used for the NTLMSSP server
 237                  *
 238                  */
 239                 dns_name = get_mydnsfullname();
 240                 if (dns_name == NULL) {
 241                         dns_name = "";
 242                 }
 243
 244                 dns_domain = get_mydnsdomname(tmp_ctx);
 245                 if (dns_domain == NULL) {
 246                         dns_domain = "";
 247                 }
 248
 249                 gensec_settings->server_dns_name = strlower_talloc(gensec_settings, dns_name);
 250                 if (gensec_settings->server_dns_name == NULL) {
 251                         TALLOC_FREE(tmp_ctx);
 252                         return NT_STATUS_NO_MEMORY;
 253                 }
 254
 255                 gensec_settings->server_dns_domain = strlower_talloc(gensec_settings, dns_domain);
 256                 if (gensec_settings->server_dns_domain == NULL) {
 257                         TALLOC_FREE(tmp_ctx);
 258                         return NT_STATUS_NO_MEMORY;
 259                 }
 260
 261                 gensec_settings->backends = talloc_zero_array(gensec_settings,
 262                                                 struct gensec_security_ops *, 4);
 263                 if (gensec_settings->backends == NULL) {
 264                         TALLOC_FREE(tmp_ctx);
 265                         return NT_STATUS_NO_MEMORY;
 266                 }
 267
 268                 gensec_init();
 269
 270                 /* These need to be in priority order, krb5 before NTLMSSP */
 271 #if defined(HAVE_KRB5)
 272                 gensec_settings->backends[idx++] = &gensec_gse_krb5_security_ops;
 273 #endif
 274
 275                 gensec_settings->backends[idx++] = gensec_security_by_oid(NULL, GENSEC_OID_NTLMSSP);
 276
 277                 gensec_settings->backends[idx++] = gensec_security_by_oid(NULL,
 278                                                         GENSEC_OID_SPNEGO);
 279
 280                 /*
 281                  * This is anonymous for now, because we just use it
 282                  * to set the kerberos state at the moment
 283                  */
 284                 server_credentials = cli_credentials_init_anon(tmp_ctx);
 285                 if (!server_credentials) {
 286                         DEBUG(0, ("auth_generic_prepare: Failed to init server credentials\n"));
 287                         return NT_STATUS_NO_MEMORY;
 288                 }
 289
 290                 cli_credentials_set_conf(server_credentials, lp_ctx);
 291
 292                 if (lp_security() == SEC_ADS || USE_KERBEROS_KEYTAB) {
 293                         cli_credentials_set_kerberos_state(server_credentials, CRED_AUTO_USE_KERBEROS);
 294                 } else {
 295                         cli_credentials_set_kerberos_state(server_credentials, CRED_DONT_USE_KERBEROS);
 296                 }
 297
 298                 nt_status = gensec_server_start(tmp_ctx, gensec_settings,
 299                                                 auth4_context, &gensec_security);
 300
 301                 if (!NT_STATUS_IS_OK(nt_status)) {
 302                         TALLOC_FREE(tmp_ctx);
 303                         return nt_status;
 304                 }
 305
 306                 gensec_set_credentials(gensec_security, server_credentials);
 307
 308                 talloc_unlink(tmp_ctx, lp_ctx);
 309                 talloc_unlink(tmp_ctx, server_credentials);
 310                 talloc_unlink(tmp_ctx, gensec_settings);
 311                 talloc_unlink(tmp_ctx, auth4_context);
 312         }
 313
 314         nt_status = gensec_set_remote_address(gensec_security,
 315                                               remote_address);
 316         if (!NT_STATUS_IS_OK(nt_status)) {
 317                 TALLOC_FREE(tmp_ctx);
 318                 return nt_status;
 319         }
 320
 321         *gensec_security_out = talloc_steal(mem_ctx, gensec_security);
 322         TALLOC_FREE(tmp_ctx);
 323         return NT_STATUS_OK;
 324 }
 325
 326 NTSTATUS auth_check_password_session_info(struct auth4_context *auth_context,
 327                                           TALLOC_CTX *mem_ctx,
 328                                           struct auth_usersupplied_info *user_info,
 329                                           struct auth_session_info **session_info)
 330 {
 331         NTSTATUS nt_status;
 332         void *server_info;
 333
 334         nt_status = auth_context->check_ntlm_password(auth_context,
 335                                                       talloc_tos(),
 336                                                       user_info,
 337                                                       &server_info, NULL, NULL);
 338
 339         if (NT_STATUS_IS_OK(nt_status)) {
 340                 nt_status = auth_context->generate_session_info(auth_context,
 341                                                                 mem_ctx,
 342                                                                 server_info,
 343                                                                 user_info->client.account_name,
 344                                                                 AUTH_SESSION_INFO_UNIX_TOKEN |
 345                                                                 AUTH_SESSION_INFO_DEFAULT_GROUPS,
 346                                                                 session_info);
 347                 TALLOC_FREE(server_info);
 348         }
 349         return nt_status;
 350 }