source/libcli/ldap/ldap_bind.c

   1 /*
   2    Unix SMB/CIFS mplementation.
   3
   4    LDAP bind calls
   5
   6    Copyright (C) Andrew Tridgell  2005
   7    Copyright (C) Volker Lendecke  2004
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 2 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program; if not, write to the Free Software
  21    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  22
  23 */
  24
  25 #include "includes.h"
  26 #include "libcli/ldap/ldap_client.h"
  27 #include "auth/auth.h"
  28
  29 static struct ldap_message *new_ldap_simple_bind_msg(struct ldap_connection *conn,
  30                                                      const char *dn, const char *pw)
  31 {
  32         struct ldap_message *res;
  33
  34         res = new_ldap_message(conn);
  35         if (!res) {
  36                 return NULL;
  37         }
  38
  39         res->type = LDAP_TAG_BindRequest;
  40         res->r.BindRequest.version = 3;
  41         res->r.BindRequest.dn = talloc_strdup(res, dn);
  42         res->r.BindRequest.mechanism = LDAP_AUTH_MECH_SIMPLE;
  43         res->r.BindRequest.creds.password = talloc_strdup(res, pw);
  44
  45         return res;
  46 }
  47
  48
  49 /*
  50   perform a simple username/password bind
  51 */
  52 NTSTATUS ldap_bind_simple(struct ldap_connection *conn,
  53                           const char *userdn, const char *password)
  54 {
  55         struct ldap_request *req;
  56         struct ldap_message *msg;
  57         const char *dn, *pw;
  58         NTSTATUS status;
  59
  60         if (conn == NULL) {
  61                 return NT_STATUS_INVALID_CONNECTION;
  62         }
  63
  64         if (userdn) {
  65                 dn = userdn;
  66         } else {
  67                 if (conn->auth_dn) {
  68                         dn = conn->auth_dn;
  69                 } else {
  70                         dn = "";
  71                 }
  72         }
  73
  74         if (password) {
  75                 pw = password;
  76         } else {
  77                 if (conn->simple_pw) {
  78                         pw = conn->simple_pw;
  79                 } else {
  80                         pw = "";
  81                 }
  82         }
  83
  84         msg = new_ldap_simple_bind_msg(conn, dn, pw);
  85         NT_STATUS_HAVE_NO_MEMORY(msg);
  86
  87         /* send the request */
  88         req = ldap_request_send(conn, msg);
  89         talloc_free(msg);
  90         NT_STATUS_HAVE_NO_MEMORY(req);
  91
  92         /* wait for replies */
  93         status = ldap_request_wait(req);
  94         if (!NT_STATUS_IS_OK(status)) {
  95                 talloc_free(req);
  96                 return status;
  97         }
  98
  99         /* check its a valid reply */
 100         msg = req->replies[0];
 101         if (msg->type != LDAP_TAG_BindResponse) {
 102                 talloc_free(req);
 103                 return NT_STATUS_UNEXPECTED_NETWORK_ERROR;
 104         }
 105
 106         status = ldap_check_response(conn, &msg->r.BindResponse.response);
 107
 108         talloc_free(req);
 109
 110         return status;
 111 }
 112
 113
 114 static struct ldap_message *new_ldap_sasl_bind_msg(struct ldap_connection *conn,
 115                                                    const char *sasl_mechanism,
 116                                                    DATA_BLOB *secblob)
 117 {
 118         struct ldap_message *res;
 119
 120         res = new_ldap_message(conn);
 121         if (!res) {
 122                 return NULL;
 123         }
 124
 125         res->type = LDAP_TAG_BindRequest;
 126         res->r.BindRequest.version = 3;
 127         res->r.BindRequest.dn = "";
 128         res->r.BindRequest.mechanism = LDAP_AUTH_MECH_SASL;
 129         res->r.BindRequest.creds.SASL.mechanism = talloc_strdup(res, sasl_mechanism);
 130         res->r.BindRequest.creds.SASL.secblob = *secblob;
 131
 132         return res;
 133 }
 134
 135
 136 /*
 137   perform a sasl bind using the given credentials
 138 */
 139 NTSTATUS ldap_bind_sasl(struct ldap_connection *conn, struct cli_credentials *creds)
 140 {
 141         NTSTATUS status;
 142         TALLOC_CTX *tmp_ctx = NULL;
 143
 144         DATA_BLOB input = data_blob(NULL, 0);
 145         DATA_BLOB output = data_blob(NULL, 0);
 146
 147         struct ldap_message **sasl_mechs_msgs;
 148         struct ldap_SearchResEntry *search;
 149         int count, i;
 150
 151         const char **sasl_names;
 152         const struct gensec_security_ops **mechs;
 153
 154         static const char *supported_sasl_mech_attrs[] = {
 155                 "supportedSASLMechanisms",
 156                 NULL
 157         };
 158
 159         status = gensec_client_start(conn, &conn->gensec, NULL);
 160         if (!NT_STATUS_IS_OK(status)) {
 161                 DEBUG(0, ("Failed to start GENSEC engine (%s)\n", nt_errstr(status)));
 162                 goto failed;
 163         }
 164
 165         gensec_want_feature(conn->gensec, 0 | GENSEC_FEATURE_SIGN | GENSEC_FEATURE_SEAL);
 166
 167         status = gensec_set_credentials(conn->gensec, creds);
 168         if (!NT_STATUS_IS_OK(status)) {
 169                 DEBUG(1, ("Failed to set GENSEC creds: %s\n",
 170                           nt_errstr(status)));
 171                 goto failed;
 172         }
 173
 174         status = gensec_set_target_hostname(conn->gensec, conn->host);
 175         if (!NT_STATUS_IS_OK(status)) {
 176                 DEBUG(1, ("Failed to set GENSEC target hostname: %s\n",
 177                           nt_errstr(status)));
 178                 goto failed;
 179         }
 180
 181         status = gensec_set_target_service(conn->gensec, "ldap");
 182         if (!NT_STATUS_IS_OK(status)) {
 183                 DEBUG(1, ("Failed to set GENSEC target service: %s\n",
 184                           nt_errstr(status)));
 185                 goto failed;
 186         }
 187
 188         status = ildap_search(conn, "", LDAP_SEARCH_SCOPE_BASE, "", supported_sasl_mech_attrs,
 189                               False, &sasl_mechs_msgs);
 190         if (!NT_STATUS_IS_OK(status)) {
 191                 DEBUG(1, ("Failed to inquire of target's available sasl mechs in rootdse search: %s\n",
 192                           nt_errstr(status)));
 193                 goto failed;
 194         }
 195
 196         count = ildap_count_entries(conn, sasl_mechs_msgs);
 197         if (count != 1) {
 198                 DEBUG(1, ("Failed to inquire of target's available sasl mechs in rootdse search: wrong number of replies: %d\n",
 199                           count));
 200                 goto failed;
 201         }
 202
 203         tmp_ctx = talloc_new(conn);
 204         if (tmp_ctx == NULL) goto failed;
 205
 206         search = &sasl_mechs_msgs[0]->r.SearchResultEntry;
 207         if (search->num_attributes != 1) {
 208                 DEBUG(1, ("Failed to inquire of target's available sasl mechs in rootdse search: wrong number of attributes: %d\n",
 209                           search->num_attributes));
 210                 goto failed;
 211         }
 212
 213         sasl_names = talloc_array(tmp_ctx, const char *, search->attributes[0].num_values + 1);
 214         if (!sasl_names) {
 215                 DEBUG(1, ("talloc_arry(char *, %d) failed\n",
 216                           count));
 217                 goto failed;
 218         }
 219
 220         for (i=0; i<search->attributes[0].num_values; i++) {
 221                 sasl_names[i] = (const char *)search->attributes[0].values[i].data;
 222         }
 223         sasl_names[i] = NULL;
 224
 225         mechs = gensec_security_by_sasl(conn->gensec, tmp_ctx, sasl_names);
 226         if (!mechs || !mechs[0]) {
 227                 DEBUG(1, ("None of the %d proposed SASL mechs were acceptable\n",
 228                           count));
 229                 goto failed;
 230         }
 231
 232         status = gensec_start_mech_by_ops(conn->gensec, mechs[0]);
 233         if (!NT_STATUS_IS_OK(status)) {
 234                 DEBUG(1, ("Failed to set GENSEC client mechanism: %s/%s %s\n",
 235                           mechs[0]->name, mechs[0]->sasl_name, nt_errstr(status)));
 236                 goto failed;
 237         }
 238
 239         while (1) {
 240                 NTSTATUS gensec_status;
 241                 struct ldap_message *response;
 242                 struct ldap_message *msg;
 243                 struct ldap_request *req;
 244                 int result = LDAP_OTHER;
 245
 246                 status = gensec_update(conn->gensec, tmp_ctx,
 247                                        input,
 248                                        &output);
 249                 /* The status value here, from GENSEC is vital to the security
 250                  * of the system.  Even if the other end accepts, if GENSEC
 251                  * claims 'MORE_PROCESSING_REQUIRED' then you must keep
 252                  * feeding it blobs, or else the remote host/attacker might
 253                  * avoid mutal authentication requirements.
 254                  *
 255                  * Likewise, you must not feed GENSEC too much (after the OK),
 256                  * it doesn't like that either
 257                  */
 258
 259                 gensec_status = status;
 260
 261                 if (!NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED) &&
 262                     !NT_STATUS_IS_OK(status)) {
 263                         break;
 264                 }
 265                 if (output.length == 0) {
 266                         break;
 267                 }
 268
 269                 msg = new_ldap_sasl_bind_msg(tmp_ctx, "GSS-SPNEGO", &output);
 270                 if (msg == NULL) {
 271                         status = NT_STATUS_NO_MEMORY;
 272                         goto failed;
 273                 }
 274
 275                 req = ldap_request_send(conn, msg);
 276                 if (req == NULL) {
 277                         status = NT_STATUS_NO_MEMORY;
 278                         goto failed;
 279                 }
 280                 talloc_steal(tmp_ctx, req);
 281
 282                 status = ldap_result_n(req, 0, &response);
 283                 if (!NT_STATUS_IS_OK(status)) {
 284                         goto failed;
 285                 }
 286
 287                 if (response->type != LDAP_TAG_BindResponse) {
 288                         status = NT_STATUS_UNEXPECTED_NETWORK_ERROR;
 289                         goto failed;
 290                 }
 291
 292                 result = response->r.BindResponse.response.resultcode;
 293
 294                 if (result != LDAP_SUCCESS && result != LDAP_SASL_BIND_IN_PROGRESS) {
 295                         status = ldap_check_response(conn,
 296                                                      &response->r.BindResponse.response);
 297                         break;
 298                 }
 299
 300                 /* This is where we check if GENSEC wanted to be fed more data */
 301                 if (!NT_STATUS_EQUAL(gensec_status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 302                         break;
 303                 }
 304                 input = response->r.BindResponse.SASL.secblob;
 305         }
 306
 307         if (NT_STATUS_IS_OK(status) &&
 308             (gensec_have_feature(conn->gensec, GENSEC_FEATURE_SEAL) ||
 309              gensec_have_feature(conn->gensec, GENSEC_FEATURE_SIGN))) {
 310                 conn->enable_wrap = True;
 311         }
 312
 313         talloc_free(tmp_ctx);
 314         return status;
 315
 316 failed:
 317         talloc_free(tmp_ctx);
 318         talloc_free(conn->gensec);
 319         conn->gensec = NULL;
 320         return status;
 321 }