source3/libads/authdata.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    kerberos authorization data (PAC) utility library
   4    Copyright (C) Jim McDonough <jmcd@us.ibm.com> 2003
   5    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2004-2005
   6    Copyright (C) Andrew Tridgell 2001
   7    Copyright (C) Luke Howard 2002-2003
   8    Copyright (C) Stefan Metzmacher 2004-2005
   9    Copyright (C) Guenther Deschner 2005,2007,2008
  10
  11    This program is free software; you can redistribute it and/or modify
  12    it under the terms of the GNU General Public License as published by
  13    the Free Software Foundation; either version 3 of the License, or
  14    (at your option) any later version.
  15
  16    This program is distributed in the hope that it will be useful,
  17    but WITHOUT ANY WARRANTY; without even the implied warranty of
  18    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19    GNU General Public License for more details.
  20
  21    You should have received a copy of the GNU General Public License
  22    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  23 */
  24
  25 #include "includes.h"
  26 #include "librpc/gen_ndr/ndr_krb5pac.h"
  27 #include "smb_krb5.h"
  28 #include "libads/kerberos_proto.h"
  29 #include "auth/common_auth.h"
  30 #include "lib/param/param.h"
  31 #include "librpc/crypto/gse.h"
  32 #include "auth/gensec/gensec.h"
  33 #include "auth/gensec/gensec_internal.h" /* TODO: remove this */
  34 #include "../libcli/auth/spnego.h"
  35 #include "krb5_errs.h"
  36
  37 #ifdef HAVE_KRB5
  38
  39 #include "auth/kerberos/pac_utils.h"
  40
  41 struct smb_krb5_context;
  42
  43 /****************************************************************
  44 Callback to get the PAC_LOGON_INFO from the blob
  45 ****************************************************************/
  46 static NTSTATUS kerberos_fetch_pac(struct auth4_context *auth_ctx,
  47                                    TALLOC_CTX *mem_ctx,
  48                                    struct smb_krb5_context *smb_krb5_context,
  49                                    DATA_BLOB *pac_blob,
  50                                    const char *princ_name,
  51                                    const struct tsocket_address *remote_address,
  52                                    uint32_t session_info_flags,
  53                                    struct auth_session_info **session_info)
  54 {
  55         TALLOC_CTX *tmp_ctx;
  56         struct PAC_DATA *pac_data = NULL;
  57         struct PAC_DATA_CTR *pac_data_ctr = NULL;
  58         NTSTATUS status = NT_STATUS_INTERNAL_ERROR;
  59
  60         tmp_ctx = talloc_new(mem_ctx);
  61         if (!tmp_ctx) {
  62                 return NT_STATUS_NO_MEMORY;
  63         }
  64
  65         if (pac_blob != NULL) {
  66                 status = kerberos_decode_pac(tmp_ctx,
  67                                              *pac_blob,
  68                                              NULL,
  69                                              NULL,
  70                                              NULL,
  71                                              NULL,
  72                                              0,
  73                                              &pac_data);
  74                 if (!NT_STATUS_IS_OK(status)) {
  75                         goto done;
  76                 }
  77
  78                 pac_data_ctr = talloc(mem_ctx, struct PAC_DATA_CTR);
  79                 if (pac_data_ctr == NULL) {
  80                         status = NT_STATUS_NO_MEMORY;
  81                         goto done;
  82                 }
  83
  84                 talloc_set_name_const(pac_data_ctr, "struct PAC_DATA_CTR");
  85
  86                 pac_data_ctr->pac_data = talloc_steal(pac_data_ctr, pac_data);
  87                 pac_data_ctr->pac_blob = data_blob_talloc(pac_data_ctr,
  88                                                           pac_blob->data,
  89                                                           pac_blob->length);
  90
  91                 auth_ctx->private_data = talloc_steal(auth_ctx, pac_data_ctr);
  92         }
  93
  94         *session_info = talloc_zero(mem_ctx, struct auth_session_info);
  95         if (!*session_info) {
  96                 status = NT_STATUS_NO_MEMORY;
  97                 goto done;
  98         }
  99         status = NT_STATUS_OK;
 100
 101 done:
 102         TALLOC_FREE(tmp_ctx);
 103
 104         return status;
 105 }
 106
 107 /*
 108  * Given the username/password, do a kinit, store the ticket in
 109  * cache_name if specified, and return the PAC_LOGON_INFO (the
 110  * structure containing the important user information such as
 111  * groups).
 112  */
 113 NTSTATUS kerberos_return_pac(TALLOC_CTX *mem_ctx,
 114                              const char *name,
 115                              const char *pass,
 116                              time_t time_offset,
 117                              time_t *expire_time,
 118                              time_t *renew_till_time,
 119                              const char *cache_name,
 120                              bool request_pac,
 121                              bool add_netbios_addr,
 122                              time_t renewable_time,
 123                              const char *impersonate_princ_s,
 124                              const char *local_service,
 125                              struct PAC_DATA_CTR **_pac_data_ctr)
 126 {
 127         krb5_error_code ret;
 128         NTSTATUS status = NT_STATUS_INVALID_PARAMETER;
 129         DATA_BLOB tkt, tkt_wrapped, ap_rep, sesskey1;
 130         const char *auth_princ = NULL;
 131         const char *cc = "MEMORY:kerberos_return_pac";
 132         struct auth_session_info *session_info;
 133         struct gensec_security *gensec_server_context;
 134         const struct gensec_security_ops **backends;
 135         struct gensec_settings *gensec_settings;
 136         size_t idx = 0;
 137         struct auth4_context *auth_context;
 138         struct loadparm_context *lp_ctx;
 139         struct PAC_DATA_CTR *pac_data_ctr = NULL;
 140
 141         TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
 142         NT_STATUS_HAVE_NO_MEMORY(tmp_ctx);
 143
 144         ZERO_STRUCT(tkt);
 145         ZERO_STRUCT(ap_rep);
 146         ZERO_STRUCT(sesskey1);
 147
 148         if (!name || !pass) {
 149                 return NT_STATUS_INVALID_PARAMETER;
 150         }
 151
 152         if (cache_name) {
 153                 cc = cache_name;
 154         }
 155
 156         if (!strchr_m(name, '@')) {
 157                 auth_princ = talloc_asprintf(mem_ctx, "%s@%s", name,
 158                         lp_realm());
 159         } else {
 160                 auth_princ = name;
 161         }
 162         NT_STATUS_HAVE_NO_MEMORY(auth_princ);
 163
 164         ret = kerberos_kinit_password_ext(auth_princ,
 165                                           pass,
 166                                           time_offset,
 167                                           expire_time,
 168                                           renew_till_time,
 169                                           cc,
 170                                           request_pac,
 171                                           add_netbios_addr,
 172                                           renewable_time,
 173                                           &status);
 174         if (ret) {
 175                 DEBUG(1,("kinit failed for '%s' with: %s (%d)\n",
 176                         auth_princ, error_message(ret), ret));
 177                 /* status already set */
 178                 goto out;
 179         }
 180
 181         DEBUG(10,("got TGT for %s in %s\n", auth_princ, cc));
 182         if (expire_time) {
 183                 DEBUGADD(10,("\tvalid until: %s (%d)\n",
 184                         http_timestring(talloc_tos(), *expire_time),
 185                         (int)*expire_time));
 186         }
 187         if (renew_till_time) {
 188                 DEBUGADD(10,("\trenewable till: %s (%d)\n",
 189                         http_timestring(talloc_tos(), *renew_till_time),
 190                         (int)*renew_till_time));
 191         }
 192
 193         /* we cannot continue with krb5 when UF_DONT_REQUIRE_PREAUTH is set,
 194          * in that case fallback to NTLM - gd */
 195
 196         if (expire_time && renew_till_time &&
 197             (*expire_time == 0) && (*renew_till_time == 0)) {
 198                 return NT_STATUS_INVALID_LOGON_TYPE;
 199         }
 200
 201         ret = ads_krb5_cli_get_ticket(mem_ctx,
 202                                       local_service,
 203                                       time_offset,
 204                                       &tkt,
 205                                       &sesskey1,
 206                                       0,
 207                                       cc,
 208                                       NULL,
 209                                       impersonate_princ_s);
 210         if (ret) {
 211                 DEBUG(1,("failed to get ticket for %s: %s\n",
 212                         local_service, error_message(ret)));
 213                 if (impersonate_princ_s) {
 214                         DEBUGADD(1,("tried S4U2SELF impersonation as: %s\n",
 215                                 impersonate_princ_s));
 216                 }
 217                 status = krb5_to_nt_status(ret);
 218                 goto out;
 219         }
 220
 221         /* wrap that up in a nice GSS-API wrapping */
 222         tkt_wrapped = spnego_gen_krb5_wrap(tmp_ctx, tkt, TOK_ID_KRB_AP_REQ);
 223         if (tkt_wrapped.data == NULL) {
 224                 status = NT_STATUS_NO_MEMORY;
 225                 goto out;
 226         }
 227
 228         auth_context = talloc_zero(tmp_ctx, struct auth4_context);
 229         if (auth_context == NULL) {
 230                 status = NT_STATUS_NO_MEMORY;
 231                 goto out;
 232         }
 233         auth_context->generate_session_info_pac = kerberos_fetch_pac;
 234
 235         lp_ctx = loadparm_init_s3(tmp_ctx, loadparm_s3_helpers());
 236         if (lp_ctx == NULL) {
 237                 status = NT_STATUS_INVALID_SERVER_STATE;
 238                 DEBUG(10, ("loadparm_init_s3 failed\n"));
 239                 goto out;
 240         }
 241
 242         gensec_settings = lpcfg_gensec_settings(tmp_ctx, lp_ctx);
 243         if (gensec_settings == NULL) {
 244                 status = NT_STATUS_NO_MEMORY;
 245                 DEBUG(10, ("lpcfg_gensec_settings failed\n"));
 246                 goto out;
 247         }
 248
 249         backends = talloc_zero_array(gensec_settings,
 250                                      const struct gensec_security_ops *, 2);
 251         if (backends == NULL) {
 252                 status = NT_STATUS_NO_MEMORY;
 253                 goto out;
 254         }
 255         gensec_settings->backends = backends;
 256
 257         gensec_init();
 258
 259         backends[idx++] = &gensec_gse_krb5_security_ops;
 260
 261         status = gensec_server_start(tmp_ctx, gensec_settings,
 262                                         auth_context, &gensec_server_context);
 263
 264         if (!NT_STATUS_IS_OK(status)) {
 265                 DEBUG(1, (__location__ "Failed to start server-side GENSEC to validate a Kerberos ticket: %s\n", nt_errstr(status)));
 266                 goto out;
 267         }
 268
 269         talloc_unlink(tmp_ctx, lp_ctx);
 270         talloc_unlink(tmp_ctx, gensec_settings);
 271         talloc_unlink(tmp_ctx, auth_context);
 272
 273         /* Session info is not complete, do not pass to auth log */
 274         gensec_want_feature(gensec_server_context, GENSEC_FEATURE_NO_AUTHZ_LOG);
 275
 276         status = gensec_start_mech_by_oid(gensec_server_context, GENSEC_OID_KERBEROS5);
 277         if (!NT_STATUS_IS_OK(status)) {
 278                 DEBUG(1, (__location__ "Failed to start server-side GENSEC krb5 to validate a Kerberos ticket: %s\n", nt_errstr(status)));
 279                 goto out;
 280         }
 281
 282         /* Do a client-server update dance */
 283         status = gensec_update(gensec_server_context, tmp_ctx, tkt_wrapped, &ap_rep);
 284         if (!NT_STATUS_IS_OK(status)) {
 285                 DEBUG(1, ("gensec_update() failed: %s\n", nt_errstr(status)));
 286                 goto out;
 287         }
 288
 289         /* Now return the PAC information to the callers.  We ingore
 290          * the session_info and instead pick out the PAC via the
 291          * private_data on the auth_context */
 292         status = gensec_session_info(gensec_server_context, tmp_ctx, &session_info);
 293         if (!NT_STATUS_IS_OK(status)) {
 294                 DEBUG(1, ("Unable to obtain PAC via gensec_session_info\n"));
 295                 goto out;
 296         }
 297
 298         pac_data_ctr = talloc_get_type_abort(gensec_server_context->auth_context->private_data,
 299                                              struct PAC_DATA_CTR);
 300         if (pac_data_ctr == NULL) {
 301                 DEBUG(1,("no PAC\n"));
 302                 status = NT_STATUS_INVALID_PARAMETER;
 303                 goto out;
 304         }
 305
 306         *_pac_data_ctr = talloc_move(mem_ctx, &pac_data_ctr);
 307
 308 out:
 309         talloc_free(tmp_ctx);
 310         if (cc != cache_name) {
 311                 ads_kdestroy(cc);
 312         }
 313
 314         data_blob_free(&tkt);
 315         data_blob_free(&ap_rep);
 316         data_blob_free(&sesskey1);
 317
 318         return status;
 319 }
 320
 321 #endif