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 #include "auth/kerberos/pac_utils.h"
  38
  39 struct smb_krb5_context;
  40
  41 /****************************************************************
  42 Callback to get the PAC_LOGON_INFO from the blob
  43 ****************************************************************/
  44 static NTSTATUS kerberos_fetch_pac(struct auth4_context *auth_ctx,
  45                                    TALLOC_CTX *mem_ctx,
  46                                    struct smb_krb5_context *smb_krb5_context,
  47                                    DATA_BLOB *pac_blob,
  48                                    const char *princ_name,
  49                                    const struct tsocket_address *remote_address,
  50                                    uint32_t session_info_flags,
  51                                    struct auth_session_info **session_info)
  52 {
  53         TALLOC_CTX *tmp_ctx;
  54         struct PAC_DATA *pac_data = NULL;
  55         struct PAC_LOGON_INFO *logon_info = NULL;
  56         unsigned int i;
  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) {
  65                 status = kerberos_decode_pac(tmp_ctx,
  66                                      *pac_blob,
  67                                      NULL, NULL, NULL, NULL, 0, &pac_data);
  68                 if (!NT_STATUS_IS_OK(status)) {
  69                         goto done;
  70                 }
  71
  72                 /* get logon name and logon info */
  73                 for (i = 0; i < pac_data->num_buffers; i++) {
  74                         struct PAC_BUFFER *data_buf = &pac_data->buffers[i];
  75
  76                         switch (data_buf->type) {
  77                         case PAC_TYPE_LOGON_INFO:
  78                                 if (!data_buf->info) {
  79                                         break;
  80                                 }
  81                                 logon_info = data_buf->info->logon_info.info;
  82                                 break;
  83                         default:
  84                                 break;
  85                         }
  86                 }
  87                 if (!logon_info) {
  88                         DEBUG(1, ("Invalid PAC data, missing logon info!\n"));
  89                         status = NT_STATUS_NOT_FOUND;
  90                         goto done;
  91                 }
  92         }
  93         talloc_set_name_const(logon_info, "struct PAC_LOGON_INFO");
  94
  95         auth_ctx->private_data = talloc_steal(auth_ctx, logon_info);
  96         *session_info = talloc_zero(mem_ctx, struct auth_session_info);
  97         if (!*session_info) {
  98                 status = NT_STATUS_NO_MEMORY;
  99                 goto done;
 100         }
 101         status = NT_STATUS_OK;
 102
 103 done:
 104         TALLOC_FREE(tmp_ctx);
 105
 106         return status;
 107 }
 108
 109 /*
 110  * Given the username/password, do a kinit, store the ticket in
 111  * cache_name if specified, and return the PAC_LOGON_INFO (the
 112  * structure containing the important user information such as
 113  * groups).
 114  */
 115 NTSTATUS kerberos_return_pac(TALLOC_CTX *mem_ctx,
 116                              const char *name,
 117                              const char *pass,
 118                              time_t time_offset,
 119                              time_t *expire_time,
 120                              time_t *renew_till_time,
 121                              const char *cache_name,
 122                              bool request_pac,
 123                              bool add_netbios_addr,
 124                              time_t renewable_time,
 125                              const char *impersonate_princ_s,
 126                              struct PAC_LOGON_INFO **_logon_info)
 127 {
 128         krb5_error_code ret;
 129         NTSTATUS status = NT_STATUS_INVALID_PARAMETER;
 130         DATA_BLOB tkt, tkt_wrapped, ap_rep, sesskey1;
 131         const char *auth_princ = NULL;
 132         const char *local_service = NULL;
 133         const char *cc = "MEMORY:kerberos_return_pac";
 134         struct auth_session_info *session_info;
 135         struct gensec_security *gensec_server_context;
 136
 137         struct gensec_settings *gensec_settings;
 138         size_t idx = 0;
 139         struct auth4_context *auth_context;
 140         struct loadparm_context *lp_ctx;
 141         struct PAC_LOGON_INFO *logon_info = NULL;
 142
 143         TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
 144         NT_STATUS_HAVE_NO_MEMORY(tmp_ctx);
 145
 146         ZERO_STRUCT(tkt);
 147         ZERO_STRUCT(ap_rep);
 148         ZERO_STRUCT(sesskey1);
 149
 150         if (!name || !pass) {
 151                 return NT_STATUS_INVALID_PARAMETER;
 152         }
 153
 154         if (cache_name) {
 155                 cc = cache_name;
 156         }
 157
 158         if (!strchr_m(name, '@')) {
 159                 auth_princ = talloc_asprintf(mem_ctx, "%s@%s", name,
 160                         lp_realm());
 161         } else {
 162                 auth_princ = name;
 163         }
 164         NT_STATUS_HAVE_NO_MEMORY(auth_princ);
 165
 166         local_service = talloc_asprintf(mem_ctx, "%s$@%s",
 167                                         lp_netbios_name(), lp_realm());
 168         NT_STATUS_HAVE_NO_MEMORY(local_service);
 169
 170         ret = kerberos_kinit_password_ext(auth_princ,
 171                                           pass,
 172                                           time_offset,
 173                                           expire_time,
 174                                           renew_till_time,
 175                                           cc,
 176                                           request_pac,
 177                                           add_netbios_addr,
 178                                           renewable_time,
 179                                           &status);
 180         if (ret) {
 181                 DEBUG(1,("kinit failed for '%s' with: %s (%d)\n",
 182                         auth_princ, error_message(ret), ret));
 183                 /* status already set */
 184                 goto out;
 185         }
 186
 187         DEBUG(10,("got TGT for %s in %s\n", auth_princ, cc));
 188         if (expire_time) {
 189                 DEBUGADD(10,("\tvalid until: %s (%d)\n",
 190                         http_timestring(talloc_tos(), *expire_time),
 191                         (int)*expire_time));
 192         }
 193         if (renew_till_time) {
 194                 DEBUGADD(10,("\trenewable till: %s (%d)\n",
 195                         http_timestring(talloc_tos(), *renew_till_time),
 196                         (int)*renew_till_time));
 197         }
 198
 199         /* we cannot continue with krb5 when UF_DONT_REQUIRE_PREAUTH is set,
 200          * in that case fallback to NTLM - gd */
 201
 202         if (expire_time && renew_till_time &&
 203             (*expire_time == 0) && (*renew_till_time == 0)) {
 204                 return NT_STATUS_INVALID_LOGON_TYPE;
 205         }
 206
 207         ret = cli_krb5_get_ticket(mem_ctx,
 208                                   local_service,
 209                                   time_offset,
 210                                   &tkt,
 211                                   &sesskey1,
 212                                   0,
 213                                   cc,
 214                                   NULL,
 215                                   impersonate_princ_s);
 216         if (ret) {
 217                 DEBUG(1,("failed to get ticket for %s: %s\n",
 218                         local_service, error_message(ret)));
 219                 if (impersonate_princ_s) {
 220                         DEBUGADD(1,("tried S4U2SELF impersonation as: %s\n",
 221                                 impersonate_princ_s));
 222                 }
 223                 status = krb5_to_nt_status(ret);
 224                 goto out;
 225         }
 226
 227         /* wrap that up in a nice GSS-API wrapping */
 228         tkt_wrapped = spnego_gen_krb5_wrap(tmp_ctx, tkt, TOK_ID_KRB_AP_REQ);
 229         if (tkt_wrapped.data == NULL) {
 230                 status = NT_STATUS_NO_MEMORY;
 231                 goto out;
 232         }
 233
 234         auth_context = talloc_zero(tmp_ctx, struct auth4_context);
 235         if (auth_context == NULL) {
 236                 status = NT_STATUS_NO_MEMORY;
 237                 goto out;
 238         }
 239         auth_context->generate_session_info_pac = kerberos_fetch_pac;
 240
 241         lp_ctx = loadparm_init_s3(tmp_ctx, loadparm_s3_context());
 242         if (lp_ctx == NULL) {
 243                 status = NT_STATUS_INVALID_SERVER_STATE;
 244                 DEBUG(10, ("loadparm_init_s3 failed\n"));
 245                 goto out;
 246         }
 247
 248         gensec_settings = lpcfg_gensec_settings(tmp_ctx, lp_ctx);
 249         if (lp_ctx == NULL) {
 250                 status = NT_STATUS_NO_MEMORY;
 251                 DEBUG(10, ("lpcfg_gensec_settings failed\n"));
 252                 goto out;
 253         }
 254
 255         gensec_settings->backends = talloc_zero_array(gensec_settings,
 256                                                       struct gensec_security_ops *, 2);
 257         if (gensec_settings->backends == NULL) {
 258                 status = NT_STATUS_NO_MEMORY;
 259                 goto out;
 260         }
 261
 262         gensec_init();
 263
 264         gensec_settings->backends[idx++] = &gensec_gse_krb5_security_ops;
 265
 266         status = gensec_server_start(tmp_ctx, gensec_settings,
 267                                         auth_context, &gensec_server_context);
 268
 269         if (!NT_STATUS_IS_OK(status)) {
 270                 DEBUG(1, (__location__ "Failed to start server-side GENSEC to validate a Kerberos ticket: %s\n", nt_errstr(status)));
 271                 goto out;
 272         }
 273
 274         talloc_unlink(tmp_ctx, lp_ctx);
 275         talloc_unlink(tmp_ctx, gensec_settings);
 276         talloc_unlink(tmp_ctx, auth_context);
 277
 278         status = gensec_start_mech_by_oid(gensec_server_context, GENSEC_OID_KERBEROS5);
 279         if (!NT_STATUS_IS_OK(status)) {
 280                 DEBUG(1, (__location__ "Failed to start server-side GENSEC krb5 to validate a Kerberos ticket: %s\n", nt_errstr(status)));
 281                 goto out;
 282         }
 283
 284         /* Do a client-server update dance */
 285         status = gensec_update(gensec_server_context, tmp_ctx, NULL, tkt_wrapped, &ap_rep);
 286         if (!NT_STATUS_IS_OK(status)) {
 287                 DEBUG(1, ("gensec_update() failed: %s\n", nt_errstr(status)));
 288                 goto out;
 289         }
 290
 291         /* Now return the PAC information to the callers.  We ingore
 292          * the session_info and instead pick out the PAC via the
 293          * private_data on the auth_context */
 294         status = gensec_session_info(gensec_server_context, tmp_ctx, &session_info);
 295         if (!NT_STATUS_IS_OK(status)) {
 296                 DEBUG(1, ("Unable to obtain PAC via gensec_session_info\n"));
 297                 goto out;
 298         }
 299
 300         logon_info = talloc_get_type_abort(gensec_server_context->auth_context->private_data,
 301                                            struct PAC_LOGON_INFO);
 302         if (logon_info == NULL) {
 303                 DEBUG(1,("no PAC\n"));
 304                 status = NT_STATUS_INVALID_PARAMETER;
 305                 goto out;
 306         }
 307
 308         *_logon_info = talloc_move(mem_ctx, &logon_info);
 309
 310 out:
 311         talloc_free(tmp_ctx);
 312         if (cc != cache_name) {
 313                 ads_kdestroy(cc);
 314         }
 315
 316         data_blob_free(&tkt);
 317         data_blob_free(&ap_rep);
 318         data_blob_free(&sesskey1);
 319
 320         return status;
 321 }
 322
 323 #endif