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
  35 #ifdef HAVE_KRB5
  36
  37 struct smb_krb5_context;
  38
  39 /****************************************************************
  40 Callback to get the PAC_LOGON_INFO from the blob
  41 ****************************************************************/
  42 static NTSTATUS kerberos_fetch_pac(struct auth4_context *auth_ctx,
  43                                    TALLOC_CTX *mem_ctx,
  44                                    struct smb_krb5_context *smb_krb5_context,
  45                                    DATA_BLOB *pac_blob,
  46                                    const char *princ_name,
  47                                    const struct tsocket_address *remote_address,
  48                                    uint32_t session_info_flags,
  49                                    struct auth_session_info **session_info)
  50 {
  51         TALLOC_CTX *tmp_ctx;
  52         struct PAC_DATA *pac_data = NULL;
  53         struct PAC_LOGON_INFO *logon_info = NULL;
  54         unsigned int i;
  55         NTSTATUS status = NT_STATUS_INTERNAL_ERROR;
  56
  57         tmp_ctx = talloc_new(mem_ctx);
  58         if (!tmp_ctx) {
  59                 return NT_STATUS_NO_MEMORY;
  60         }
  61
  62         if (pac_blob) {
  63                 status = kerberos_decode_pac(tmp_ctx,
  64                                      *pac_blob,
  65                                      NULL, NULL, NULL, NULL, 0, &pac_data);
  66                 if (!NT_STATUS_IS_OK(status)) {
  67                         goto done;
  68                 }
  69
  70                 /* get logon name and logon info */
  71                 for (i = 0; i < pac_data->num_buffers; i++) {
  72                         struct PAC_BUFFER *data_buf = &pac_data->buffers[i];
  73
  74                         switch (data_buf->type) {
  75                         case PAC_TYPE_LOGON_INFO:
  76                                 if (!data_buf->info) {
  77                                         break;
  78                                 }
  79                                 logon_info = data_buf->info->logon_info.info;
  80                                 break;
  81                         default:
  82                                 break;
  83                         }
  84                 }
  85                 if (!logon_info) {
  86                         DEBUG(1, ("Invalid PAC data, missing logon info!\n"));
  87                         status = NT_STATUS_NOT_FOUND;
  88                         goto done;
  89                 }
  90         }
  91         talloc_set_name_const(logon_info, "struct PAC_LOGON_INFO");
  92
  93         auth_ctx->private_data = talloc_steal(auth_ctx, logon_info);
  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                              struct PAC_LOGON_INFO **_logon_info)
 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 *local_service = NULL;
 131         const char *cc = "MEMORY:kerberos_return_pac";
 132         struct auth_session_info *session_info;
 133         struct gensec_security *gensec_server_context;
 134
 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_LOGON_INFO *logon_info = 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         local_service = talloc_asprintf(mem_ctx, "%s$@%s",
 165                                         lp_netbios_name(), lp_realm());
 166         NT_STATUS_HAVE_NO_MEMORY(local_service);
 167
 168         ret = kerberos_kinit_password_ext(auth_princ,
 169                                           pass,
 170                                           time_offset,
 171                                           expire_time,
 172                                           renew_till_time,
 173                                           cc,
 174                                           request_pac,
 175                                           add_netbios_addr,
 176                                           renewable_time,
 177                                           &status);
 178         if (ret) {
 179                 DEBUG(1,("kinit failed for '%s' with: %s (%d)\n",
 180                         auth_princ, error_message(ret), ret));
 181                 /* status already set */
 182                 goto out;
 183         }
 184
 185         DEBUG(10,("got TGT for %s in %s\n", auth_princ, cc));
 186         if (expire_time) {
 187                 DEBUGADD(10,("\tvalid until: %s (%d)\n",
 188                         http_timestring(talloc_tos(), *expire_time),
 189                         (int)*expire_time));
 190         }
 191         if (renew_till_time) {
 192                 DEBUGADD(10,("\trenewable till: %s (%d)\n",
 193                         http_timestring(talloc_tos(), *renew_till_time),
 194                         (int)*renew_till_time));
 195         }
 196
 197         /* we cannot continue with krb5 when UF_DONT_REQUIRE_PREAUTH is set,
 198          * in that case fallback to NTLM - gd */
 199
 200         if (expire_time && renew_till_time &&
 201             (*expire_time == 0) && (*renew_till_time == 0)) {
 202                 return NT_STATUS_INVALID_LOGON_TYPE;
 203         }
 204
 205         ret = cli_krb5_get_ticket(mem_ctx,
 206                                   local_service,
 207                                   time_offset,
 208                                   &tkt,
 209                                   &sesskey1,
 210                                   0,
 211                                   cc,
 212                                   NULL,
 213                                   impersonate_princ_s);
 214         if (ret) {
 215                 DEBUG(1,("failed to get ticket for %s: %s\n",
 216                         local_service, error_message(ret)));
 217                 if (impersonate_princ_s) {
 218                         DEBUGADD(1,("tried S4U2SELF impersonation as: %s\n",
 219                                 impersonate_princ_s));
 220                 }
 221                 status = krb5_to_nt_status(ret);
 222                 goto out;
 223         }
 224
 225         /* wrap that up in a nice GSS-API wrapping */
 226         tkt_wrapped = spnego_gen_krb5_wrap(tmp_ctx, tkt, TOK_ID_KRB_AP_REQ);
 227         if (tkt_wrapped.data == NULL) {
 228                 status = NT_STATUS_NO_MEMORY;
 229                 goto out;
 230         }
 231
 232         auth_context = talloc_zero(tmp_ctx, struct auth4_context);
 233         if (auth_context == NULL) {
 234                 status = NT_STATUS_NO_MEMORY;
 235                 goto out;
 236         }
 237         auth_context->generate_session_info_pac = kerberos_fetch_pac;
 238
 239         lp_ctx = loadparm_init_s3(tmp_ctx, loadparm_s3_context());
 240         if (lp_ctx == NULL) {
 241                 status = NT_STATUS_INVALID_SERVER_STATE;
 242                 DEBUG(10, ("loadparm_init_s3 failed\n"));
 243                 goto out;
 244         }
 245
 246         gensec_settings = lpcfg_gensec_settings(tmp_ctx, lp_ctx);
 247         if (lp_ctx == NULL) {
 248                 status = NT_STATUS_NO_MEMORY;
 249                 DEBUG(10, ("lpcfg_gensec_settings failed\n"));
 250                 goto out;
 251         }
 252
 253         gensec_settings->backends = talloc_zero_array(gensec_settings,
 254                                                       struct gensec_security_ops *, 2);
 255         if (gensec_settings->backends == NULL) {
 256                 status = NT_STATUS_NO_MEMORY;
 257                 goto out;
 258         }
 259
 260         gensec_init();
 261
 262         gensec_settings->backends[idx++] = &gensec_gse_krb5_security_ops;
 263
 264         status = gensec_server_start(tmp_ctx, gensec_settings,
 265                                         auth_context, &gensec_server_context);
 266
 267         if (!NT_STATUS_IS_OK(status)) {
 268                 DEBUG(1, (__location__ "Failed to start server-side GENSEC to validate a Kerberos ticket: %s\n", nt_errstr(status)));
 269                 goto out;
 270         }
 271
 272         talloc_unlink(tmp_ctx, lp_ctx);
 273         talloc_unlink(tmp_ctx, gensec_settings);
 274         talloc_unlink(tmp_ctx, auth_context);
 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, NULL, 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         logon_info = talloc_get_type_abort(gensec_server_context->auth_context->private_data,
 299                                            struct PAC_LOGON_INFO);
 300         if (logon_info == NULL) {
 301                 DEBUG(1,("no PAC\n"));
 302                 status = NT_STATUS_INVALID_PARAMETER;
 303                 goto out;
 304         }
 305
 306         *_logon_info = talloc_move(mem_ctx, &logon_info);
 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