source4/libcli/finddcs_cldap.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    a composite API for finding a DC and its name via CLDAP
   5
   6    Copyright (C) Andrew Tridgell 2010
   7    Copyright (C) Andrew Bartlett 2010
   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 3 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, see <http://www.gnu.org/licenses/>.
  21 */
  22
  23 #include "include/includes.h"
  24 #include <tevent.h>
  25 #include "libcli/resolve/resolve.h"
  26 #include "lib/messaging/messaging.h"
  27 #include "libcli/libcli.h"
  28 #include "libcli/cldap/cldap.h"
  29 #include "libcli/finddcs.h"
  30 #include "libcli/security/dom_sid.h"
  31 #include "lib/util/tevent_ntstatus.h"
  32 #include "libcli/composite/composite.h"
  33
  34 struct finddcs_cldap_state {
  35         struct tevent_context *ev;
  36         struct tevent_req *req;
  37         const char *dns_domain_name;
  38         struct dom_sid *domain_sid;
  39         const char **srv_addresses;
  40         uint32_t minimum_dc_flags;
  41         uint32_t srv_address_index;
  42         struct cldap_socket *cldap;
  43         struct cldap_netlogon *netlogon;
  44 };
  45
  46 static void finddcs_cldap_srv_resolved(struct composite_context *ctx);
  47 static void finddcs_cldap_netlogon_replied(struct tevent_req *req);
  48
  49
  50 /*
  51  * find a list of DCs via DNS/CLDAP
  52  *
  53  */
  54 struct tevent_req *finddcs_cldap_send(TALLOC_CTX *mem_ctx,
  55                                       struct finddcs *io,
  56                                       struct resolve_context *resolve_ctx,
  57                                       struct tevent_context *event_ctx)
  58 {
  59         struct finddcs_cldap_state *state;
  60         struct tevent_req *req;
  61         const char *srv_name;
  62         struct composite_context *creq;
  63         struct nbt_name name;
  64
  65         req = tevent_req_create(mem_ctx, &state, struct finddcs_cldap_state);
  66         if (req == NULL) {
  67                 return NULL;
  68         }
  69
  70         state->req = req;
  71         state->ev = event_ctx;
  72         state->minimum_dc_flags = io->in.minimum_dc_flags;
  73         state->dns_domain_name = talloc_strdup(state, io->in.dns_domain_name);
  74         if (tevent_req_nomem(state->dns_domain_name, req)) {
  75                 return tevent_req_post(req, event_ctx);
  76         }
  77
  78         if (io->in.domain_sid) {
  79                 state->domain_sid = dom_sid_dup(state, io->in.domain_sid);
  80                 if (tevent_req_nomem(state->domain_sid, req)) {
  81                         return tevent_req_post(req, event_ctx);
  82                 }
  83         } else {
  84                 state->domain_sid = NULL;
  85         }
  86
  87         /* step1: lookup _ldap._tcp.* */
  88         if (io->in.site_name) {
  89                 srv_name = talloc_asprintf(state, "_ldap._tcp.%s._sites.%s",
  90                                            io->in.site_name, io->in.dns_domain_name);
  91         } else {
  92                 srv_name = talloc_asprintf(state, "_ldap._tcp.%s", io->in.dns_domain_name);
  93         }
  94
  95         make_nbt_name(&name, srv_name, 0);
  96
  97         creq = resolve_name_ex_send(resolve_ctx, state,
  98                                     RESOLVE_NAME_FLAG_FORCE_DNS | RESOLVE_NAME_FLAG_DNS_SRV,
  99                                     0, &name, event_ctx);
 100         if (tevent_req_nomem(creq, req)) {
 101                 return tevent_req_post(req, event_ctx);
 102         }
 103         creq->async.fn = finddcs_cldap_srv_resolved;
 104         creq->async.private_data = state;
 105
 106         return req;
 107 }
 108
 109
 110 /*
 111   fire off a CLDAP query to the next server
 112  */
 113 static void finddcs_cldap_next_server(struct finddcs_cldap_state *state)
 114 {
 115         struct tevent_req *subreq;
 116
 117         if (state->srv_addresses[state->srv_address_index] == NULL) {
 118                 tevent_req_nterror(state->req, NT_STATUS_OBJECT_NAME_NOT_FOUND);
 119                 return;
 120         }
 121
 122         state->netlogon = talloc_zero(state, struct cldap_netlogon);
 123         if (tevent_req_nomem(state->netlogon, state->req)) {
 124                 return;
 125         }
 126
 127         state->netlogon->in.dest_address = state->srv_addresses[state->srv_address_index];
 128         /* we should get the port from the SRV response */
 129         state->netlogon->in.dest_port = 389;
 130         state->netlogon->in.realm = state->dns_domain_name;
 131         if (state->domain_sid) {
 132                 state->netlogon->in.domain_sid = dom_sid_string(state, state->domain_sid);
 133                 if (tevent_req_nomem(state->netlogon->in.domain_sid, state->req)) {
 134                         return;
 135                 }
 136         }
 137         state->netlogon->in.acct_control = -1;
 138         state->netlogon->in.version =
 139                 NETLOGON_NT_VERSION_5 |
 140                 NETLOGON_NT_VERSION_5EX |
 141                 NETLOGON_NT_VERSION_IP;
 142         state->netlogon->in.map_response = true;
 143
 144         subreq = cldap_netlogon_send(state, state->cldap, state->netlogon);
 145         if (tevent_req_nomem(subreq, state->req)) {
 146                 return;
 147         }
 148
 149         tevent_req_set_callback(subreq, finddcs_cldap_netlogon_replied, state);
 150 }
 151
 152
 153 /*
 154   we have a response from a CLDAP server for a netlogon request
 155  */
 156 static void finddcs_cldap_netlogon_replied(struct tevent_req *subreq)
 157 {
 158         struct finddcs_cldap_state *state;
 159         NTSTATUS status;
 160
 161         state = tevent_req_callback_data(subreq, struct finddcs_cldap_state);
 162
 163         status = cldap_netlogon_recv(subreq, state->netlogon, state->netlogon);
 164         if (!NT_STATUS_IS_OK(status)) {
 165                 state->srv_address_index++;
 166                 finddcs_cldap_next_server(state);
 167                 return;
 168         }
 169         if (state->minimum_dc_flags !=
 170             (state->minimum_dc_flags & state->netlogon->out.netlogon.data.nt5_ex.server_type)) {
 171                 /* the server didn't match the minimum requirements */
 172                 DEBUG(4,(__location__ ": Skipping DC %s with server_type=0x%08x\n",
 173                          state->srv_addresses[state->srv_address_index],
 174                          state->netlogon->out.netlogon.data.nt5_ex.server_type));
 175                 state->srv_address_index++;
 176                 finddcs_cldap_next_server(state);
 177                 return;
 178         }
 179
 180         talloc_free(subreq);
 181         tevent_req_done(state->req);
 182 }
 183
 184
 185 /*
 186  * Having got a DNS SRV answer, fire off the first CLDAP request
 187  */
 188 static void finddcs_cldap_srv_resolved(struct composite_context *ctx)
 189 {
 190         struct finddcs_cldap_state *state =
 191                 talloc_get_type(ctx->async.private_data, struct finddcs_cldap_state);
 192         NTSTATUS status;
 193
 194         status = resolve_name_multiple_recv(ctx, state, &state->srv_addresses);
 195         if (tevent_req_nterror(state->req, status)) {
 196                 return;
 197         }
 198
 199         state->srv_address_index = 0;
 200
 201         status = cldap_socket_init(state, state->ev, NULL, NULL, &state->cldap);
 202         if (tevent_req_nterror(state->req, status)) {
 203                 return;
 204         }
 205
 206         finddcs_cldap_next_server(state);
 207 }
 208
 209
 210 NTSTATUS finddcs_cldap_recv(struct tevent_req *req, TALLOC_CTX *mem_ctx, struct finddcs *io)
 211 {
 212         struct finddcs_cldap_state *state = tevent_req_data(req, struct finddcs_cldap_state);
 213         bool ok;
 214         NTSTATUS status;
 215
 216         ok = tevent_req_poll(req, state->ev);
 217         if (!ok) {
 218                 talloc_free(req);
 219                 return NT_STATUS_INTERNAL_ERROR;
 220         }
 221         status = tevent_req_simple_recv_ntstatus(req);
 222         if (NT_STATUS_IS_OK(status)) {
 223                 talloc_steal(mem_ctx, state->netlogon);
 224                 io->out.netlogon = state->netlogon->out.netlogon;
 225                 io->out.address = talloc_steal(mem_ctx, state->srv_addresses[state->srv_address_index]);
 226         }
 227         tevent_req_received(req);
 228         return status;
 229 }
 230
 231 NTSTATUS finddcs_cldap(TALLOC_CTX *mem_ctx,
 232                        struct finddcs *io,
 233                        struct resolve_context *resolve_ctx,
 234                        struct tevent_context *event_ctx)
 235 {
 236         NTSTATUS status;
 237         struct tevent_req *req = finddcs_cldap_send(mem_ctx,
 238                                                     io,
 239                                                     resolve_ctx,
 240                                                     event_ctx);
 241         status = finddcs_cldap_recv(req, mem_ctx, io);
 242         talloc_free(req);
 243         return status;
 244 }