source4/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.h"
  27 #include "libcli/ldap/ldap_client.h"
  28 #include "auth/auth.h"
  29
  30 static struct ldap_message *new_ldap_simple_bind_msg(struct ldap_connection *conn,
  31                                                      const char *dn, const char *pw)
  32 {
  33         struct ldap_message *res;
  34
  35         res = new_ldap_message(conn);
  36         if (!res) {
  37                 return NULL;
  38         }
  39
  40         res->type = LDAP_TAG_BindRequest;
  41         res->r.BindRequest.version = 3;
  42         res->r.BindRequest.dn = talloc_strdup(res, dn);
  43         res->r.BindRequest.mechanism = LDAP_AUTH_MECH_SIMPLE;
  44         res->r.BindRequest.creds.password = talloc_strdup(res, pw);
  45         res->controls = NULL;
  46
  47         return res;
  48 }
  49
  50
  51 /*
  52   perform a simple username/password bind
  53 */
  54 NTSTATUS ldap_bind_simple(struct ldap_connection *conn,
  55                           const char *userdn, const char *password)
  56 {
  57         struct ldap_request *req;
  58         struct ldap_message *msg;
  59         const char *dn, *pw;
  60         NTSTATUS status;
  61
  62         if (conn == NULL) {
  63                 return NT_STATUS_INVALID_CONNECTION;
  64         }
  65
  66         if (userdn) {
  67                 dn = userdn;
  68         } else {
  69                 if (conn->auth_dn) {
  70                         dn = conn->auth_dn;
  71                 } else {
  72                         dn = "";
  73                 }
  74         }
  75
  76         if (password) {
  77                 pw = password;
  78         } else {
  79                 if (conn->simple_pw) {
  80                         pw = conn->simple_pw;
  81                 } else {
  82                         pw = "";
  83                 }
  84         }
  85
  86         msg = new_ldap_simple_bind_msg(conn, dn, pw);
  87         NT_STATUS_HAVE_NO_MEMORY(msg);
  88
  89         /* send the request */
  90         req = ldap_request_send(conn, msg);
  91         talloc_free(msg);
  92         NT_STATUS_HAVE_NO_MEMORY(req);
  93
  94         /* wait for replies */
  95         status = ldap_request_wait(req);
  96         if (!NT_STATUS_IS_OK(status)) {
  97                 talloc_free(req);
  98                 return status;
  99         }
 100
 101         /* check its a valid reply */
 102         msg = req->replies[0];
 103         if (msg->type != LDAP_TAG_BindResponse) {
 104                 talloc_free(req);
 105                 return NT_STATUS_UNEXPECTED_NETWORK_ERROR;
 106         }
 107
 108         status = ldap_check_response(conn, &msg->r.BindResponse.response);
 109
 110         talloc_free(req);
 111
 112         return status;
 113 }
 114
 115
 116 static struct ldap_message *new_ldap_sasl_bind_msg(struct ldap_connection *conn,
 117                                                    const char *sasl_mechanism,
 118                                                    DATA_BLOB *secblob)
 119 {
 120         struct ldap_message *res;
 121
 122         res = new_ldap_message(conn);
 123         if (!res) {
 124                 return NULL;
 125         }
 126
 127         res->type = LDAP_TAG_BindRequest;
 128         res->r.BindRequest.version = 3;
 129         res->r.BindRequest.dn = "";
 130         res->r.BindRequest.mechanism = LDAP_AUTH_MECH_SASL;
 131         res->r.BindRequest.creds.SASL.mechanism = talloc_strdup(res, sasl_mechanism);
 132         if (secblob) {
 133                 res->r.BindRequest.creds.SASL.secblob = talloc(res, DATA_BLOB);
 134                 if (!res->r.BindRequest.creds.SASL.secblob) {
 135                         talloc_free(res);
 136                         return NULL;
 137                 }
 138                 *res->r.BindRequest.creds.SASL.secblob = *secblob;
 139         } else {
 140                 res->r.BindRequest.creds.SASL.secblob = NULL;
 141         }
 142         res->controls = NULL;
 143
 144         return res;
 145 }
 146
 147
 148 /*
 149   perform a sasl bind using the given credentials
 150 */
 151 NTSTATUS ldap_bind_sasl(struct ldap_connection *conn, struct cli_credentials *creds)
 152 {
 153         NTSTATUS status;
 154         TALLOC_CTX *tmp_ctx = NULL;
 155
 156         DATA_BLOB input = data_blob(NULL, 0);
 157         DATA_BLOB output = data_blob(NULL, 0);
 158
 159         struct ldap_message **sasl_mechs_msgs;
 160         struct ldap_SearchResEntry *search;
 161         int count, i;
 162
 163         const char **sasl_names;
 164
 165         static const char *supported_sasl_mech_attrs[] = {
 166                 "supportedSASLMechanisms",
 167                 NULL
 168         };
 169
 170         status = gensec_client_start(conn, &conn->gensec, NULL);
 171         if (!NT_STATUS_IS_OK(status)) {
 172                 DEBUG(0, ("Failed to start GENSEC engine (%s)\n", nt_errstr(status)));
 173                 goto failed;
 174         }
 175
 176         gensec_want_feature(conn->gensec, 0 | GENSEC_FEATURE_SIGN | GENSEC_FEATURE_SEAL);
 177
 178         status = gensec_set_credentials(conn->gensec, creds);
 179         if (!NT_STATUS_IS_OK(status)) {
 180                 DEBUG(1, ("Failed to set GENSEC creds: %s\n",
 181                           nt_errstr(status)));
 182                 goto failed;
 183         }
 184
 185         status = gensec_set_target_hostname(conn->gensec, conn->host);
 186         if (!NT_STATUS_IS_OK(status)) {
 187                 DEBUG(1, ("Failed to set GENSEC target hostname: %s\n",
 188                           nt_errstr(status)));
 189                 goto failed;
 190         }
 191
 192         status = gensec_set_target_service(conn->gensec, "ldap");
 193         if (!NT_STATUS_IS_OK(status)) {
 194                 DEBUG(1, ("Failed to set GENSEC target service: %s\n",
 195                           nt_errstr(status)));
 196                 goto failed;
 197         }
 198
 199         status = ildap_search(conn, "", LDAP_SEARCH_SCOPE_BASE, "", supported_sasl_mech_attrs,
 200                               False, NULL, NULL, &sasl_mechs_msgs);
 201         if (!NT_STATUS_IS_OK(status)) {
 202                 DEBUG(1, ("Failed to inquire of target's available sasl mechs in rootdse search: %s\n",
 203                           nt_errstr(status)));
 204                 goto failed;
 205         }
 206
 207         count = ildap_count_entries(conn, sasl_mechs_msgs);
 208         if (count != 1) {
 209                 DEBUG(1, ("Failed to inquire of target's available sasl mechs in rootdse search: wrong number of replies: %d\n",
 210                           count));
 211                 goto failed;
 212         }
 213
 214         tmp_ctx = talloc_new(conn);
 215         if (tmp_ctx == NULL) goto failed;
 216
 217         search = &sasl_mechs_msgs[0]->r.SearchResultEntry;
 218         if (search->num_attributes != 1) {
 219                 DEBUG(1, ("Failed to inquire of target's available sasl mechs in rootdse search: wrong number of attributes: %d\n",
 220                           search->num_attributes));
 221                 goto failed;
 222         }
 223
 224         sasl_names = talloc_array(tmp_ctx, const char *, search->attributes[0].num_values + 1);
 225         if (!sasl_names) {
 226                 DEBUG(1, ("talloc_arry(char *, %d) failed\n",
 227                           count));
 228                 goto failed;
 229         }
 230
 231         for (i=0; i<search->attributes[0].num_values; i++) {
 232                 sasl_names[i] = (const char *)search->attributes[0].values[i].data;
 233         }
 234         sasl_names[i] = NULL;
 235
 236         status = gensec_start_mech_by_sasl_list(conn->gensec, sasl_names);
 237         if (!NT_STATUS_IS_OK(status)) {
 238                 DEBUG(1, ("None of the %d proposed SASL mechs were acceptable: %s\n",
 239                           count, nt_errstr(status)));
 240                 goto failed;
 241         }
 242
 243         while (1) {
 244                 NTSTATUS gensec_status;
 245                 struct ldap_message *response;
 246                 struct ldap_message *msg;
 247                 struct ldap_request *req;
 248                 int result = LDAP_OTHER;
 249
 250                 status = gensec_update(conn->gensec, tmp_ctx,
 251                                        input,
 252                                        &output);
 253                 /* The status value here, from GENSEC is vital to the security
 254                  * of the system.  Even if the other end accepts, if GENSEC
 255                  * claims 'MORE_PROCESSING_REQUIRED' then you must keep
 256                  * feeding it blobs, or else the remote host/attacker might
 257                  * avoid mutal authentication requirements.
 258                  *
 259                  * Likewise, you must not feed GENSEC too much (after the OK),
 260                  * it doesn't like that either
 261                  */
 262
 263                 gensec_status = status;
 264
 265                 if (!NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED) &&
 266                     !NT_STATUS_IS_OK(status)) {
 267                         break;
 268                 }
 269                 if (NT_STATUS_IS_OK(status) && output.length == 0) {
 270                         break;
 271                 }
 272
 273                 /* Perhaps we should make gensec_start_mech_by_sasl_list() return the name we got? */
 274                 msg = new_ldap_sasl_bind_msg(tmp_ctx, conn->gensec->ops->sasl_name, (output.data?&output:NULL));
 275                 if (msg == NULL) {
 276                         status = NT_STATUS_NO_MEMORY;
 277                         goto failed;
 278                 }
 279
 280                 req = ldap_request_send(conn, msg);
 281                 if (req == NULL) {
 282                         status = NT_STATUS_NO_MEMORY;
 283                         goto failed;
 284                 }
 285                 talloc_steal(tmp_ctx, req);
 286
 287                 status = ldap_result_n(req, 0, &response);
 288                 if (!NT_STATUS_IS_OK(status)) {
 289                         goto failed;
 290                 }
 291
 292                 if (response->type != LDAP_TAG_BindResponse) {
 293                         status = NT_STATUS_UNEXPECTED_NETWORK_ERROR;
 294                         goto failed;
 295                 }
 296
 297                 result = response->r.BindResponse.response.resultcode;
 298
 299                 if (result != LDAP_SUCCESS && result != LDAP_SASL_BIND_IN_PROGRESS) {
 300                         status = ldap_check_response(conn,
 301                                                      &response->r.BindResponse.response);
 302                         break;
 303                 }
 304
 305                 /* This is where we check if GENSEC wanted to be fed more data */
 306                 if (!NT_STATUS_EQUAL(gensec_status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 307                         break;
 308                 }
 309                 if (response->r.BindResponse.SASL.secblob) {
 310                         input = *response->r.BindResponse.SASL.secblob;
 311                 } else {
 312                         input = data_blob(NULL, 0);
 313                 }
 314         }
 315
 316         if (NT_STATUS_IS_OK(status) &&
 317             (gensec_have_feature(conn->gensec, GENSEC_FEATURE_SEAL) ||
 318              gensec_have_feature(conn->gensec, GENSEC_FEATURE_SIGN))) {
 319                 conn->enable_wrap = True;
 320         }
 321
 322         talloc_free(tmp_ctx);
 323         return status;
 324
 325 failed:
 326         talloc_free(tmp_ctx);
 327         talloc_free(conn->gensec);
 328         conn->gensec = NULL;
 329         return status;
 330 }