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 "../libcli/auth/spnego.h"
  34 #include "auth/kerberos/pac_utils.h"
  35
  36 #ifdef HAVE_KRB5
  37
  38 struct smb_krb5_context;
  39
  40 /****************************************************************
  41 Callback to get the PAC_LOGON_INFO from the blob
  42 ****************************************************************/
  43 static NTSTATUS kerberos_fetch_pac(struct auth4_context *auth_ctx,
  44                                    TALLOC_CTX *mem_ctx,
  45                                    struct smb_krb5_context *smb_krb5_context,
  46                                    DATA_BLOB *pac_blob,
  47                                    const char *princ_name,
  48                                    const struct tsocket_address *remote_address,
  49                                    uint32_t session_info_flags,
  50                                    struct auth_session_info **session_info)
  51 {
  52         TALLOC_CTX *tmp_ctx;
  53         struct PAC_DATA *pac_data = NULL;
  54         struct PAC_LOGON_INFO *logon_info = NULL;
  55         unsigned int i;
  56         NTSTATUS status = NT_STATUS_INTERNAL_ERROR;
  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                 status = kerberos_decode_pac(tmp_ctx,
  65                                      *pac_blob,
  66                                      NULL, NULL, NULL, NULL, 0, &pac_data);
  67                 if (!NT_STATUS_IS_OK(status)) {
  68                         goto done;
  69                 }
  70
  71                 /* get logon name and logon info */
  72                 for (i = 0; i < pac_data->num_buffers; i++) {
  73                         struct PAC_BUFFER *data_buf = &pac_data->buffers[i];
  74
  75                         switch (data_buf->type) {
  76                         case PAC_TYPE_LOGON_INFO:
  77                                 if (!data_buf->info) {
  78                                         break;
  79                                 }
  80                                 logon_info = data_buf->info->logon_info.info;
  81                                 break;
  82                         default:
  83                                 break;
  84                         }
  85                 }
  86                 if (!logon_info) {
  87                         DEBUG(1, ("Invalid PAC data, missing logon info!\n"));
  88                         status = NT_STATUS_NOT_FOUND;
  89                         goto done;
  90                 }
  91         }
  92         talloc_set_name_const(logon_info, "struct PAC_LOGON_INFO");
  93
  94         auth_ctx->private_data = talloc_steal(auth_ctx, logon_info);
  95         *session_info = talloc_zero(mem_ctx, struct auth_session_info);
  96         if (!*session_info) {
  97                 status = NT_STATUS_NO_MEMORY;
  98                 goto done;
  99         }
 100         status = NT_STATUS_OK;
 101
 102 done:
 103         TALLOC_FREE(tmp_ctx);
 104
 105         return status;
 106 }
 107
 108 /*
 109  * Given the username/password, do a kinit, store the ticket in
 110  * cache_name if specified, and return the PAC_LOGON_INFO (the
 111  * structure containing the important user information such as
 112  * groups).
 113  */
 114 NTSTATUS kerberos_return_pac(TALLOC_CTX *mem_ctx,
 115                              const char *name,
 116                              const char *pass,
 117                              time_t time_offset,
 118                              time_t *expire_time,
 119                              time_t *renew_till_time,
 120                              const char *cache_name,
 121                              bool request_pac,
 122                              bool add_netbios_addr,
 123                              time_t renewable_time,
 124                              const char *impersonate_princ_s,
 125                              struct PAC_LOGON_INFO **_logon_info)
 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 *local_service = NULL;
 132         const char *cc = "MEMORY:kerberos_return_pac";
 133         struct auth_session_info *session_info;
 134         struct gensec_security *gensec_server_context;
 135
 136         struct gensec_settings *gensec_settings;
 137         size_t idx = 0;
 138         struct auth4_context *auth_context;
 139         struct loadparm_context *lp_ctx;
 140         struct PAC_LOGON_INFO *logon_info = NULL;
 141
 142         TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
 143         NT_STATUS_HAVE_NO_MEMORY(tmp_ctx);
 144
 145         ZERO_STRUCT(tkt);
 146         ZERO_STRUCT(ap_rep);
 147         ZERO_STRUCT(sesskey1);
 148
 149         if (!name || !pass) {
 150                 return NT_STATUS_INVALID_PARAMETER;
 151         }
 152
 153         if (cache_name) {
 154                 cc = cache_name;
 155         }
 156
 157         if (!strchr_m(name, '@')) {
 158                 auth_princ = talloc_asprintf(mem_ctx, "%s@%s", name,
 159                         lp_realm());
 160         } else {
 161                 auth_princ = name;
 162         }
 163         NT_STATUS_HAVE_NO_MEMORY(auth_princ);
 164
 165         local_service = talloc_asprintf(mem_ctx, "%s$@%s",
 166                                         lp_netbios_name(), lp_realm());
 167         NT_STATUS_HAVE_NO_MEMORY(local_service);
 168
 169         ret = kerberos_kinit_password_ext(auth_princ,
 170                                           pass,
 171                                           time_offset,
 172                                           expire_time,
 173                                           renew_till_time,
 174                                           cc,
 175                                           request_pac,
 176                                           add_netbios_addr,
 177                                           renewable_time,
 178                                           &status);
 179         if (ret) {
 180                 DEBUG(1,("kinit failed for '%s' with: %s (%d)\n",
 181                         auth_princ, error_message(ret), ret));
 182                 /* status already set */
 183                 goto out;
 184         }
 185
 186         DEBUG(10,("got TGT for %s in %s\n", auth_princ, cc));
 187         if (expire_time) {
 188                 DEBUGADD(10,("\tvalid until: %s (%d)\n",
 189                         http_timestring(talloc_tos(), *expire_time),
 190                         (int)*expire_time));
 191         }
 192         if (renew_till_time) {
 193                 DEBUGADD(10,("\trenewable till: %s (%d)\n",
 194                         http_timestring(talloc_tos(), *renew_till_time),
 195                         (int)*renew_till_time));
 196         }
 197
 198         /* we cannot continue with krb5 when UF_DONT_REQUIRE_PREAUTH is set,
 199          * in that case fallback to NTLM - gd */
 200
 201         if (expire_time && renew_till_time &&
 202             (*expire_time == 0) && (*renew_till_time == 0)) {
 203                 return NT_STATUS_INVALID_LOGON_TYPE;
 204         }
 205
 206         ret = cli_krb5_get_ticket(mem_ctx,
 207                                   local_service,
 208                                   time_offset,
 209                                   &tkt,
 210                                   &sesskey1,
 211                                   0,
 212                                   cc,
 213                                   NULL,
 214                                   impersonate_princ_s);
 215         if (ret) {
 216                 DEBUG(1,("failed to get ticket for %s: %s\n",
 217                         local_service, error_message(ret)));
 218                 if (impersonate_princ_s) {
 219                         DEBUGADD(1,("tried S4U2SELF impersonation as: %s\n",
 220                                 impersonate_princ_s));
 221                 }
 222                 status = krb5_to_nt_status(ret);
 223                 goto out;
 224         }
 225
 226         /* wrap that up in a nice GSS-API wrapping */
 227         tkt_wrapped = spnego_gen_krb5_wrap(tmp_ctx, tkt, TOK_ID_KRB_AP_REQ);
 228         if (tkt_wrapped.data == NULL) {
 229                 status = NT_STATUS_NO_MEMORY;
 230                 goto out;
 231         }
 232
 233         auth_context = talloc_zero(tmp_ctx, struct auth4_context);
 234         if (auth_context == NULL) {
 235                 status = NT_STATUS_NO_MEMORY;
 236                 goto out;
 237         }
 238         auth_context->generate_session_info_pac = kerberos_fetch_pac;
 239
 240         lp_ctx = loadparm_init_s3(tmp_ctx, loadparm_s3_context());
 241         if (lp_ctx == NULL) {
 242                 status = NT_STATUS_INVALID_SERVER_STATE;
 243                 DEBUG(10, ("loadparm_init_s3 failed\n"));
 244                 goto out;
 245         }
 246
 247         gensec_settings = lpcfg_gensec_settings(tmp_ctx, lp_ctx);
 248         if (lp_ctx == NULL) {
 249                 status = NT_STATUS_NO_MEMORY;
 250                 DEBUG(10, ("lpcfg_gensec_settings failed\n"));
 251                 goto out;
 252         }
 253
 254         gensec_settings->backends = talloc_zero_array(gensec_settings,
 255                                                       struct gensec_security_ops *, 2);
 256         if (gensec_settings->backends == NULL) {
 257                 status = NT_STATUS_NO_MEMORY;
 258                 goto out;
 259         }
 260
 261         gensec_init();
 262
 263         gensec_settings->backends[idx++] = &gensec_gse_krb5_security_ops;
 264
 265         status = gensec_server_start(tmp_ctx, gensec_settings,
 266                                         auth_context, &gensec_server_context);
 267
 268         if (!NT_STATUS_IS_OK(status)) {
 269                 DEBUG(1, (__location__ "Failed to start server-side GENSEC to validate a Kerberos ticket: %s\n", nt_errstr(status)));
 270                 goto out;
 271         }
 272
 273         talloc_unlink(tmp_ctx, lp_ctx);
 274         talloc_unlink(tmp_ctx, gensec_settings);
 275         talloc_unlink(tmp_ctx, auth_context);
 276
 277         status = gensec_start_mech_by_oid(gensec_server_context, GENSEC_OID_KERBEROS5);
 278         if (!NT_STATUS_IS_OK(status)) {
 279                 DEBUG(1, (__location__ "Failed to start server-side GENSEC krb5 to validate a Kerberos ticket: %s\n", nt_errstr(status)));
 280                 goto out;
 281         }
 282
 283         /* Do a client-server update dance */
 284         status = gensec_update(gensec_server_context, tmp_ctx, NULL, tkt_wrapped, &ap_rep);
 285         if (!NT_STATUS_IS_OK(status)) {
 286                 DEBUG(1, ("gensec_update() failed: %s\n", nt_errstr(status)));
 287                 goto out;
 288         }
 289
 290         /* Now return the PAC information to the callers.  We ingore
 291          * the session_info and instead pick out the PAC via the
 292          * private_data on the auth_context */
 293         status = gensec_session_info(gensec_server_context, tmp_ctx, &session_info);
 294         if (!NT_STATUS_IS_OK(status)) {
 295                 DEBUG(1, ("Unable to obtain PAC via gensec_session_info\n"));
 296                 goto out;
 297         }
 298
 299         logon_info = talloc_get_type_abort(gensec_server_context->auth_context->private_data,
 300                                            struct PAC_LOGON_INFO);
 301         if (logon_info == NULL) {
 302                 DEBUG(1,("no PAC\n"));
 303                 status = NT_STATUS_INVALID_PARAMETER;
 304                 goto out;
 305         }
 306
 307         *_logon_info = talloc_move(mem_ctx, &logon_info);
 308
 309 out:
 310         talloc_free(tmp_ctx);
 311         if (cc != cache_name) {
 312                 ads_kdestroy(cc);
 313         }
 314
 315         data_blob_free(&tkt);
 316         data_blob_free(&ap_rep);
 317         data_blob_free(&sesskey1);
 318
 319         return status;
 320 }
 321
 322 #endif