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
  36 #ifdef HAVE_KRB5
  37
  38 #include "auth/kerberos/pac_utils.h"
  39
  40 struct smb_krb5_context;
  41
  42 /****************************************************************
  43 Callback to get the PAC_LOGON_INFO from the blob
  44 ****************************************************************/
  45 static NTSTATUS kerberos_fetch_pac(struct auth4_context *auth_ctx,
  46                                    TALLOC_CTX *mem_ctx,
  47                                    struct smb_krb5_context *smb_krb5_context,
  48                                    DATA_BLOB *pac_blob,
  49                                    const char *princ_name,
  50                                    const struct tsocket_address *remote_address,
  51                                    uint32_t session_info_flags,
  52                                    struct auth_session_info **session_info)
  53 {
  54         TALLOC_CTX *tmp_ctx;
  55         struct PAC_DATA *pac_data = NULL;
  56         struct PAC_DATA_CTR *pac_data_ctr = NULL;
  57         NTSTATUS status = NT_STATUS_INTERNAL_ERROR;
  58
  59         tmp_ctx = talloc_new(mem_ctx);
  60         if (!tmp_ctx) {
  61                 return NT_STATUS_NO_MEMORY;
  62         }
  63
  64         if (pac_blob != NULL) {
  65                 status = kerberos_decode_pac(tmp_ctx,
  66                                              *pac_blob,
  67                                              NULL,
  68                                              NULL,
  69                                              NULL,
  70                                              NULL,
  71                                              0,
  72                                              &pac_data);
  73                 if (!NT_STATUS_IS_OK(status)) {
  74                         goto done;
  75                 }
  76
  77                 pac_data_ctr = talloc(mem_ctx, struct PAC_DATA_CTR);
  78                 if (pac_data_ctr == NULL) {
  79                         status = NT_STATUS_NO_MEMORY;
  80                         goto done;
  81                 }
  82
  83                 talloc_set_name_const(pac_data_ctr, "struct PAC_DATA_CTR");
  84
  85                 pac_data_ctr->pac_data = talloc_steal(pac_data_ctr, pac_data);
  86                 pac_data_ctr->pac_blob = data_blob_talloc(pac_data_ctr,
  87                                                           pac_blob->data,
  88                                                           pac_blob->length);
  89
  90                 auth_ctx->private_data = talloc_steal(auth_ctx, pac_data_ctr);
  91         }
  92
  93         *session_info = talloc_zero(mem_ctx, struct auth_session_info);
  94         if (!*session_info) {
  95                 status = NT_STATUS_NO_MEMORY;
  96                 goto done;
  97         }
  98         status = NT_STATUS_OK;
  99
 100 done:
 101         TALLOC_FREE(tmp_ctx);
 102
 103         return status;
 104 }
 105
 106 /*
 107  * Given the username/password, do a kinit, store the ticket in
 108  * cache_name if specified, and return the PAC_LOGON_INFO (the
 109  * structure containing the important user information such as
 110  * groups).
 111  */
 112 NTSTATUS kerberos_return_pac(TALLOC_CTX *mem_ctx,
 113                              const char *name,
 114                              const char *pass,
 115                              time_t time_offset,
 116                              time_t *expire_time,
 117                              time_t *renew_till_time,
 118                              const char *cache_name,
 119                              bool request_pac,
 120                              bool add_netbios_addr,
 121                              time_t renewable_time,
 122                              const char *impersonate_princ_s,
 123                              const char *local_service,
 124                              struct PAC_DATA_CTR **_pac_data_ctr)
 125 {
 126         krb5_error_code ret;
 127         NTSTATUS status = NT_STATUS_INVALID_PARAMETER;
 128         DATA_BLOB tkt, tkt_wrapped, ap_rep, sesskey1;
 129         const char *auth_princ = NULL;
 130         const char *cc = "MEMORY:kerberos_return_pac";
 131         struct auth_session_info *session_info;
 132         struct gensec_security *gensec_server_context;
 133         const struct gensec_security_ops **backends;
 134         struct gensec_settings *gensec_settings;
 135         size_t idx = 0;
 136         struct auth4_context *auth_context;
 137         struct loadparm_context *lp_ctx;
 138         struct PAC_DATA_CTR *pac_data_ctr = NULL;
 139
 140         TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
 141         NT_STATUS_HAVE_NO_MEMORY(tmp_ctx);
 142
 143         ZERO_STRUCT(tkt);
 144         ZERO_STRUCT(ap_rep);
 145         ZERO_STRUCT(sesskey1);
 146
 147         if (!name || !pass) {
 148                 return NT_STATUS_INVALID_PARAMETER;
 149         }
 150
 151         if (cache_name) {
 152                 cc = cache_name;
 153         }
 154
 155         if (!strchr_m(name, '@')) {
 156                 auth_princ = talloc_asprintf(mem_ctx, "%s@%s", name,
 157                         lp_realm());
 158         } else {
 159                 auth_princ = name;
 160         }
 161         NT_STATUS_HAVE_NO_MEMORY(auth_princ);
 162
 163         ret = kerberos_kinit_password_ext(auth_princ,
 164                                           pass,
 165                                           time_offset,
 166                                           expire_time,
 167                                           renew_till_time,
 168                                           cc,
 169                                           request_pac,
 170                                           add_netbios_addr,
 171                                           renewable_time,
 172                                           &status);
 173         if (ret) {
 174                 DEBUG(1,("kinit failed for '%s' with: %s (%d)\n",
 175                         auth_princ, error_message(ret), ret));
 176                 /* status already set */
 177                 goto out;
 178         }
 179
 180         DEBUG(10,("got TGT for %s in %s\n", auth_princ, cc));
 181         if (expire_time) {
 182                 DEBUGADD(10,("\tvalid until: %s (%d)\n",
 183                         http_timestring(talloc_tos(), *expire_time),
 184                         (int)*expire_time));
 185         }
 186         if (renew_till_time) {
 187                 DEBUGADD(10,("\trenewable till: %s (%d)\n",
 188                         http_timestring(talloc_tos(), *renew_till_time),
 189                         (int)*renew_till_time));
 190         }
 191
 192         /* we cannot continue with krb5 when UF_DONT_REQUIRE_PREAUTH is set,
 193          * in that case fallback to NTLM - gd */
 194
 195         if (expire_time && renew_till_time &&
 196             (*expire_time == 0) && (*renew_till_time == 0)) {
 197                 return NT_STATUS_INVALID_LOGON_TYPE;
 198         }
 199
 200         ret = cli_krb5_get_ticket(mem_ctx,
 201                                   local_service,
 202                                   time_offset,
 203                                   &tkt,
 204                                   &sesskey1,
 205                                   0,
 206                                   cc,
 207                                   NULL,
 208                                   impersonate_princ_s);
 209         if (ret) {
 210                 DEBUG(1,("failed to get ticket for %s: %s\n",
 211                         local_service, error_message(ret)));
 212                 if (impersonate_princ_s) {
 213                         DEBUGADD(1,("tried S4U2SELF impersonation as: %s\n",
 214                                 impersonate_princ_s));
 215                 }
 216                 status = krb5_to_nt_status(ret);
 217                 goto out;
 218         }
 219
 220         /* wrap that up in a nice GSS-API wrapping */
 221         tkt_wrapped = spnego_gen_krb5_wrap(tmp_ctx, tkt, TOK_ID_KRB_AP_REQ);
 222         if (tkt_wrapped.data == NULL) {
 223                 status = NT_STATUS_NO_MEMORY;
 224                 goto out;
 225         }
 226
 227         auth_context = talloc_zero(tmp_ctx, struct auth4_context);
 228         if (auth_context == NULL) {
 229                 status = NT_STATUS_NO_MEMORY;
 230                 goto out;
 231         }
 232         auth_context->generate_session_info_pac = kerberos_fetch_pac;
 233
 234         lp_ctx = loadparm_init_s3(tmp_ctx, loadparm_s3_helpers());
 235         if (lp_ctx == NULL) {
 236                 status = NT_STATUS_INVALID_SERVER_STATE;
 237                 DEBUG(10, ("loadparm_init_s3 failed\n"));
 238                 goto out;
 239         }
 240
 241         gensec_settings = lpcfg_gensec_settings(tmp_ctx, lp_ctx);
 242         if (gensec_settings == NULL) {
 243                 status = NT_STATUS_NO_MEMORY;
 244                 DEBUG(10, ("lpcfg_gensec_settings failed\n"));
 245                 goto out;
 246         }
 247
 248         backends = talloc_zero_array(gensec_settings,
 249                                      const struct gensec_security_ops *, 2);
 250         if (backends == NULL) {
 251                 status = NT_STATUS_NO_MEMORY;
 252                 goto out;
 253         }
 254         gensec_settings->backends = backends;
 255
 256         gensec_init();
 257
 258         backends[idx++] = &gensec_gse_krb5_security_ops;
 259
 260         status = gensec_server_start(tmp_ctx, gensec_settings,
 261                                         auth_context, &gensec_server_context);
 262
 263         if (!NT_STATUS_IS_OK(status)) {
 264                 DEBUG(1, (__location__ "Failed to start server-side GENSEC to validate a Kerberos ticket: %s\n", nt_errstr(status)));
 265                 goto out;
 266         }
 267
 268         talloc_unlink(tmp_ctx, lp_ctx);
 269         talloc_unlink(tmp_ctx, gensec_settings);
 270         talloc_unlink(tmp_ctx, auth_context);
 271
 272         status = gensec_start_mech_by_oid(gensec_server_context, GENSEC_OID_KERBEROS5);
 273         if (!NT_STATUS_IS_OK(status)) {
 274                 DEBUG(1, (__location__ "Failed to start server-side GENSEC krb5 to validate a Kerberos ticket: %s\n", nt_errstr(status)));
 275                 goto out;
 276         }
 277
 278         /* Do a client-server update dance */
 279         status = gensec_update(gensec_server_context, tmp_ctx, tkt_wrapped, &ap_rep);
 280         if (!NT_STATUS_IS_OK(status)) {
 281                 DEBUG(1, ("gensec_update() failed: %s\n", nt_errstr(status)));
 282                 goto out;
 283         }
 284
 285         /* Now return the PAC information to the callers.  We ingore
 286          * the session_info and instead pick out the PAC via the
 287          * private_data on the auth_context */
 288         status = gensec_session_info(gensec_server_context, tmp_ctx, &session_info);
 289         if (!NT_STATUS_IS_OK(status)) {
 290                 DEBUG(1, ("Unable to obtain PAC via gensec_session_info\n"));
 291                 goto out;
 292         }
 293
 294         pac_data_ctr = talloc_get_type_abort(gensec_server_context->auth_context->private_data,
 295                                              struct PAC_DATA_CTR);
 296         if (pac_data_ctr == NULL) {
 297                 DEBUG(1,("no PAC\n"));
 298                 status = NT_STATUS_INVALID_PARAMETER;
 299                 goto out;
 300         }
 301
 302         *_pac_data_ctr = talloc_move(mem_ctx, &pac_data_ctr);
 303
 304 out:
 305         talloc_free(tmp_ctx);
 306         if (cc != cache_name) {
 307                 ads_kdestroy(cc);
 308         }
 309
 310         data_blob_free(&tkt);
 311         data_blob_free(&ap_rep);
 312         data_blob_free(&sesskey1);
 313
 314         return status;
 315 }
 316
 317 #endif