source4/kdc/kdc.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    KDC Server startup
   5
   6    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2005-2008
   7    Copyright (C) Andrew Tridgell        2005
   8    Copyright (C) Stefan Metzmacher      2005
   9
  10    This program is free software; you can redistribute it and/or modify
  11    it under the terms of the GNU General Public License as published by
  12    the Free Software Foundation; either version 3 of the License, or
  13    (at your option) any later version.
  14
  15    This program is distributed in the hope that it will be useful,
  16    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18    GNU General Public License for more details.
  19
  20    You should have received a copy of the GNU General Public License
  21    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  22 */
  23
  24 #include "includes.h"
  25 #include "smbd/process_model.h"
  26 #include "lib/tsocket/tsocket.h"
  27 #include "libcli/util/tstream.h"
  28 #include "lib/messaging/irpc.h"
  29 #include "librpc/gen_ndr/ndr_irpc.h"
  30 #include "librpc/gen_ndr/ndr_krb5pac.h"
  31 #include "lib/stream/packet.h"
  32 #include "lib/socket/netif.h"
  33 #include "param/param.h"
  34 #include "kdc/kdc-glue.h"
  35 #include "dsdb/samdb/samdb.h"
  36 #include "auth/session.h"
  37
  38 NTSTATUS server_service_kdc_init(void);
  39
  40 extern struct krb5plugin_windc_ftable windc_plugin_table;
  41 extern struct hdb_method hdb_samba4;
  42
  43 static NTSTATUS kdc_proxy_unavailable_error(struct kdc_server *kdc,
  44                                             TALLOC_CTX *mem_ctx,
  45                                             DATA_BLOB *out)
  46 {
  47         int kret;
  48         krb5_data k5_error_blob;
  49
  50         kret = krb5_mk_error(kdc->smb_krb5_context->krb5_context,
  51                              KRB5KDC_ERR_SVC_UNAVAILABLE, NULL, NULL,
  52                              NULL, NULL, NULL, NULL, &k5_error_blob);
  53         if (kret != 0) {
  54                 DEBUG(2,(__location__ ": Unable to form krb5 error reply\n"));
  55                 return NT_STATUS_INTERNAL_ERROR;
  56         }
  57
  58         *out = data_blob_talloc(mem_ctx, k5_error_blob.data, k5_error_blob.length);
  59         krb5_data_free(&k5_error_blob);
  60         if (!out->data) {
  61                 return NT_STATUS_NO_MEMORY;
  62         }
  63
  64         return NT_STATUS_OK;
  65 }
  66
  67 typedef enum kdc_process_ret (*kdc_process_fn_t)(struct kdc_server *kdc,
  68                                                  TALLOC_CTX *mem_ctx,
  69                                                  DATA_BLOB *input,
  70                                                  DATA_BLOB *reply,
  71                                                  struct tsocket_address *peer_addr,
  72                                                  struct tsocket_address *my_addr,
  73                                                  int datagram);
  74
  75 /* hold information about one kdc socket */
  76 struct kdc_socket {
  77         struct kdc_server *kdc;
  78         struct tsocket_address *local_address;
  79         kdc_process_fn_t process;
  80 };
  81
  82 struct kdc_tcp_call {
  83         struct kdc_tcp_connection *kdc_conn;
  84         DATA_BLOB in;
  85         DATA_BLOB out;
  86         uint8_t out_hdr[4];
  87         struct iovec out_iov[2];
  88 };
  89
  90 /*
  91   state of an open tcp connection
  92 */
  93 struct kdc_tcp_connection {
  94         /* stream connection we belong to */
  95         struct stream_connection *conn;
  96
  97         /* the kdc_server the connection belongs to */
  98         struct kdc_socket *kdc_socket;
  99
 100         struct tstream_context *tstream;
 101
 102         struct tevent_queue *send_queue;
 103 };
 104
 105
 106 static void kdc_tcp_terminate_connection(struct kdc_tcp_connection *kdcconn, const char *reason)
 107 {
 108         stream_terminate_connection(kdcconn->conn, reason);
 109 }
 110
 111 static void kdc_tcp_recv(struct stream_connection *conn, uint16_t flags)
 112 {
 113         struct kdc_tcp_connection *kdcconn = talloc_get_type(conn->private_data,
 114                                                              struct kdc_tcp_connection);
 115         /* this should never be triggered! */
 116         kdc_tcp_terminate_connection(kdcconn, "kdc_tcp_recv: called");
 117 }
 118
 119 static void kdc_tcp_send(struct stream_connection *conn, uint16_t flags)
 120 {
 121         struct kdc_tcp_connection *kdcconn = talloc_get_type(conn->private_data,
 122                                                              struct kdc_tcp_connection);
 123         /* this should never be triggered! */
 124         kdc_tcp_terminate_connection(kdcconn, "kdc_tcp_send: called");
 125 }
 126
 127 /**
 128    Wrapper for krb5_kdc_process_krb5_request, converting to/from Samba
 129    calling conventions
 130 */
 131
 132 static enum kdc_process_ret kdc_process(struct kdc_server *kdc,
 133                                         TALLOC_CTX *mem_ctx,
 134                                         DATA_BLOB *input,
 135                                         DATA_BLOB *reply,
 136                                         struct tsocket_address *peer_addr,
 137                                         struct tsocket_address *my_addr,
 138                                         int datagram_reply)
 139 {
 140         int ret;
 141         char *pa;
 142         struct sockaddr_storage ss;
 143         krb5_data k5_reply;
 144         krb5_data_zero(&k5_reply);
 145
 146         krb5_kdc_update_time(NULL);
 147
 148         ret = tsocket_address_bsd_sockaddr(peer_addr, (struct sockaddr *) &ss,
 149                                 sizeof(struct sockaddr_storage));
 150         if (ret < 0) {
 151                 return KDC_PROCESS_FAILED;
 152         }
 153         pa = tsocket_address_string(peer_addr, mem_ctx);
 154         if (pa == NULL) {
 155                 return KDC_PROCESS_FAILED;
 156         }
 157
 158         DEBUG(10,("Received KDC packet of length %lu from %s\n",
 159                                 (long)input->length - 4, pa));
 160
 161         ret = krb5_kdc_process_krb5_request(kdc->smb_krb5_context->krb5_context,
 162                                             kdc->config,
 163                                             input->data, input->length,
 164                                             &k5_reply,
 165                                             pa,
 166                                             (struct sockaddr *) &ss,
 167                                             datagram_reply);
 168         if (ret == -1) {
 169                 *reply = data_blob(NULL, 0);
 170                 return KDC_PROCESS_FAILED;
 171         }
 172
 173         if (ret == HDB_ERR_NOT_FOUND_HERE) {
 174                 *reply = data_blob(NULL, 0);
 175                 return KDC_PROCESS_PROXY;
 176         }
 177
 178         if (k5_reply.length) {
 179                 *reply = data_blob_talloc(mem_ctx, k5_reply.data, k5_reply.length);
 180                 krb5_data_free(&k5_reply);
 181         } else {
 182                 *reply = data_blob(NULL, 0);
 183         }
 184         return KDC_PROCESS_OK;
 185 }
 186
 187 static void kdc_tcp_call_proxy_done(struct tevent_req *subreq);
 188 static void kdc_tcp_call_writev_done(struct tevent_req *subreq);
 189
 190 static void kdc_tcp_call_loop(struct tevent_req *subreq)
 191 {
 192         struct kdc_tcp_connection *kdc_conn = tevent_req_callback_data(subreq,
 193                                       struct kdc_tcp_connection);
 194         struct kdc_tcp_call *call;
 195         NTSTATUS status;
 196         enum kdc_process_ret ret;
 197
 198         call = talloc(kdc_conn, struct kdc_tcp_call);
 199         if (call == NULL) {
 200                 kdc_tcp_terminate_connection(kdc_conn, "kdc_tcp_call_loop: "
 201                                 "no memory for kdc_tcp_call");
 202                 return;
 203         }
 204         call->kdc_conn = kdc_conn;
 205
 206         status = tstream_read_pdu_blob_recv(subreq,
 207                                             call,
 208                                             &call->in);
 209         TALLOC_FREE(subreq);
 210         if (!NT_STATUS_IS_OK(status)) {
 211                 const char *reason;
 212
 213                 reason = talloc_asprintf(call, "kdc_tcp_call_loop: "
 214                                          "tstream_read_pdu_blob_recv() - %s",
 215                                          nt_errstr(status));
 216                 if (!reason) {
 217                         reason = nt_errstr(status);
 218                 }
 219
 220                 kdc_tcp_terminate_connection(kdc_conn, reason);
 221                 return;
 222         }
 223
 224         DEBUG(10,("Received krb5 TCP packet of length %lu from %s\n",
 225                  (long) call->in.length,
 226                  tsocket_address_string(kdc_conn->conn->remote_address, call)));
 227
 228         /* skip length header */
 229         call->in.data +=4;
 230         call->in.length -= 4;
 231
 232         /* Call krb5 */
 233         ret = kdc_conn->kdc_socket->process(kdc_conn->kdc_socket->kdc,
 234                                            call,
 235                                            &call->in,
 236                                            &call->out,
 237                                            kdc_conn->conn->remote_address,
 238                                            kdc_conn->conn->local_address,
 239                                            0 /* Stream */);
 240         if (ret == KDC_PROCESS_FAILED) {
 241                 kdc_tcp_terminate_connection(kdc_conn,
 242                                 "kdc_tcp_call_loop: process function failed");
 243                 return;
 244         }
 245
 246         if (ret == KDC_PROCESS_PROXY) {
 247                 uint16_t port;
 248
 249                 if (!kdc_conn->kdc_socket->kdc->am_rodc) {
 250                         kdc_tcp_terminate_connection(kdc_conn,
 251                                                      "kdc_tcp_call_loop: proxying requested when not RODC");
 252                         return;
 253                 }
 254                 port = tsocket_address_inet_port(kdc_conn->conn->local_address);
 255
 256                 subreq = kdc_tcp_proxy_send(call,
 257                                             kdc_conn->conn->event.ctx,
 258                                             kdc_conn->kdc_socket->kdc,
 259                                             port,
 260                                             call->in);
 261                 if (subreq == NULL) {
 262                         kdc_tcp_terminate_connection(kdc_conn,
 263                                 "kdc_tcp_call_loop: kdc_tcp_proxy_send failed");
 264                         return;
 265                 }
 266                 tevent_req_set_callback(subreq, kdc_tcp_call_proxy_done, call);
 267                 return;
 268         }
 269
 270         /* First add the length of the out buffer */
 271         RSIVAL(call->out_hdr, 0, call->out.length);
 272         call->out_iov[0].iov_base = (char *) call->out_hdr;
 273         call->out_iov[0].iov_len = 4;
 274
 275         call->out_iov[1].iov_base = (char *) call->out.data;
 276         call->out_iov[1].iov_len = call->out.length;
 277
 278         subreq = tstream_writev_queue_send(call,
 279                                            kdc_conn->conn->event.ctx,
 280                                            kdc_conn->tstream,
 281                                            kdc_conn->send_queue,
 282                                            call->out_iov, 2);
 283         if (subreq == NULL) {
 284                 kdc_tcp_terminate_connection(kdc_conn, "kdc_tcp_call_loop: "
 285                                 "no memory for tstream_writev_queue_send");
 286                 return;
 287         }
 288         tevent_req_set_callback(subreq, kdc_tcp_call_writev_done, call);
 289
 290         /*
 291          * The krb5 tcp pdu's has the length as 4 byte (initial_read_size),
 292          * packet_full_request_u32 provides the pdu length then.
 293          */
 294         subreq = tstream_read_pdu_blob_send(kdc_conn,
 295                                             kdc_conn->conn->event.ctx,
 296                                             kdc_conn->tstream,
 297                                             4, /* initial_read_size */
 298                                             packet_full_request_u32,
 299                                             kdc_conn);
 300         if (subreq == NULL) {
 301                 kdc_tcp_terminate_connection(kdc_conn, "kdc_tcp_call_loop: "
 302                                 "no memory for tstream_read_pdu_blob_send");
 303                 return;
 304         }
 305         tevent_req_set_callback(subreq, kdc_tcp_call_loop, kdc_conn);
 306 }
 307
 308 static void kdc_tcp_call_proxy_done(struct tevent_req *subreq)
 309 {
 310         struct kdc_tcp_call *call = tevent_req_callback_data(subreq,
 311                         struct kdc_tcp_call);
 312         struct kdc_tcp_connection *kdc_conn = call->kdc_conn;
 313         NTSTATUS status;
 314
 315         status = kdc_tcp_proxy_recv(subreq, call, &call->out);
 316         TALLOC_FREE(subreq);
 317         if (!NT_STATUS_IS_OK(status)) {
 318                 /* generate an error packet */
 319                 status = kdc_proxy_unavailable_error(kdc_conn->kdc_socket->kdc,
 320                                                      call, &call->out);
 321         }
 322
 323         if (!NT_STATUS_IS_OK(status)) {
 324                 const char *reason;
 325
 326                 reason = talloc_asprintf(call, "kdc_tcp_call_proxy_done: "
 327                                          "kdc_proxy_unavailable_error - %s",
 328                                          nt_errstr(status));
 329                 if (!reason) {
 330                         reason = "kdc_tcp_call_proxy_done: kdc_proxy_unavailable_error() failed";
 331                 }
 332
 333                 kdc_tcp_terminate_connection(call->kdc_conn, reason);
 334                 return;
 335         }
 336
 337         /* First add the length of the out buffer */
 338         RSIVAL(call->out_hdr, 0, call->out.length);
 339         call->out_iov[0].iov_base = (char *) call->out_hdr;
 340         call->out_iov[0].iov_len = 4;
 341
 342         call->out_iov[1].iov_base = (char *) call->out.data;
 343         call->out_iov[1].iov_len = call->out.length;
 344
 345         subreq = tstream_writev_queue_send(call,
 346                                            kdc_conn->conn->event.ctx,
 347                                            kdc_conn->tstream,
 348                                            kdc_conn->send_queue,
 349                                            call->out_iov, 2);
 350         if (subreq == NULL) {
 351                 kdc_tcp_terminate_connection(kdc_conn, "kdc_tcp_call_loop: "
 352                                 "no memory for tstream_writev_queue_send");
 353                 return;
 354         }
 355         tevent_req_set_callback(subreq, kdc_tcp_call_writev_done, call);
 356
 357         /*
 358          * The krb5 tcp pdu's has the length as 4 byte (initial_read_size),
 359          * packet_full_request_u32 provides the pdu length then.
 360          */
 361         subreq = tstream_read_pdu_blob_send(kdc_conn,
 362                                             kdc_conn->conn->event.ctx,
 363                                             kdc_conn->tstream,
 364                                             4, /* initial_read_size */
 365                                             packet_full_request_u32,
 366                                             kdc_conn);
 367         if (subreq == NULL) {
 368                 kdc_tcp_terminate_connection(kdc_conn, "kdc_tcp_call_loop: "
 369                                 "no memory for tstream_read_pdu_blob_send");
 370                 return;
 371         }
 372         tevent_req_set_callback(subreq, kdc_tcp_call_loop, kdc_conn);
 373 }
 374
 375 static void kdc_tcp_call_writev_done(struct tevent_req *subreq)
 376 {
 377         struct kdc_tcp_call *call = tevent_req_callback_data(subreq,
 378                         struct kdc_tcp_call);
 379         int sys_errno;
 380         int rc;
 381
 382         rc = tstream_writev_queue_recv(subreq, &sys_errno);
 383         TALLOC_FREE(subreq);
 384         if (rc == -1) {
 385                 const char *reason;
 386
 387                 reason = talloc_asprintf(call, "kdc_tcp_call_writev_done: "
 388                                          "tstream_writev_queue_recv() - %d:%s",
 389                                          sys_errno, strerror(sys_errno));
 390                 if (!reason) {
 391                         reason = "kdc_tcp_call_writev_done: tstream_writev_queue_recv() failed";
 392                 }
 393
 394                 kdc_tcp_terminate_connection(call->kdc_conn, reason);
 395                 return;
 396         }
 397
 398         /* We don't care about errors */
 399
 400         talloc_free(call);
 401 }
 402
 403 /*
 404   called when we get a new connection
 405 */
 406 static void kdc_tcp_accept(struct stream_connection *conn)
 407 {
 408         struct kdc_socket *kdc_socket;
 409         struct kdc_tcp_connection *kdc_conn;
 410         struct tevent_req *subreq;
 411         int rc;
 412
 413         kdc_conn = talloc_zero(conn, struct kdc_tcp_connection);
 414         if (kdc_conn == NULL) {
 415                 stream_terminate_connection(conn,
 416                                 "kdc_tcp_accept: out of memory");
 417                 return;
 418         }
 419
 420         kdc_conn->send_queue = tevent_queue_create(conn, "kdc_tcp_accept");
 421         if (kdc_conn->send_queue == NULL) {
 422                 stream_terminate_connection(conn,
 423                                 "kdc_tcp_accept: out of memory");
 424                 return;
 425         }
 426
 427         kdc_socket = talloc_get_type(conn->private_data, struct kdc_socket);
 428
 429         TALLOC_FREE(conn->event.fde);
 430
 431         rc = tstream_bsd_existing_socket(kdc_conn,
 432                         socket_get_fd(conn->socket),
 433                         &kdc_conn->tstream);
 434         if (rc < 0) {
 435                 stream_terminate_connection(conn,
 436                                 "kdc_tcp_accept: out of memory");
 437                 return;
 438         }
 439
 440         kdc_conn->conn = conn;
 441         kdc_conn->kdc_socket = kdc_socket;
 442         conn->private_data = kdc_conn;
 443
 444         /*
 445          * The krb5 tcp pdu's has the length as 4 byte (initial_read_size),
 446          * packet_full_request_u32 provides the pdu length then.
 447          */
 448         subreq = tstream_read_pdu_blob_send(kdc_conn,
 449                                             kdc_conn->conn->event.ctx,
 450                                             kdc_conn->tstream,
 451                                             4, /* initial_read_size */
 452                                             packet_full_request_u32,
 453                                             kdc_conn);
 454         if (subreq == NULL) {
 455                 kdc_tcp_terminate_connection(kdc_conn, "kdc_tcp_accept: "
 456                                 "no memory for tstream_read_pdu_blob_send");
 457                 return;
 458         }
 459         tevent_req_set_callback(subreq, kdc_tcp_call_loop, kdc_conn);
 460 }
 461
 462 static const struct stream_server_ops kdc_tcp_stream_ops = {
 463         .name                   = "kdc_tcp",
 464         .accept_connection      = kdc_tcp_accept,
 465         .recv_handler           = kdc_tcp_recv,
 466         .send_handler           = kdc_tcp_send
 467 };
 468
 469 /* hold information about one kdc/kpasswd udp socket */
 470 struct kdc_udp_socket {
 471         struct kdc_socket *kdc_socket;
 472         struct tdgram_context *dgram;
 473         struct tevent_queue *send_queue;
 474 };
 475
 476 struct kdc_udp_call {
 477         struct kdc_udp_socket *sock;
 478         struct tsocket_address *src;
 479         DATA_BLOB in;
 480         DATA_BLOB out;
 481 };
 482
 483 static void kdc_udp_call_proxy_done(struct tevent_req *subreq);
 484 static void kdc_udp_call_sendto_done(struct tevent_req *subreq);
 485
 486 static void kdc_udp_call_loop(struct tevent_req *subreq)
 487 {
 488         struct kdc_udp_socket *sock = tevent_req_callback_data(subreq,
 489                                       struct kdc_udp_socket);
 490         struct kdc_udp_call *call;
 491         uint8_t *buf;
 492         ssize_t len;
 493         int sys_errno;
 494         enum kdc_process_ret ret;
 495
 496         call = talloc(sock, struct kdc_udp_call);
 497         if (call == NULL) {
 498                 talloc_free(call);
 499                 goto done;
 500         }
 501         call->sock = sock;
 502
 503         len = tdgram_recvfrom_recv(subreq, &sys_errno,
 504                                    call, &buf, &call->src);
 505         TALLOC_FREE(subreq);
 506         if (len == -1) {
 507                 talloc_free(call);
 508                 goto done;
 509         }
 510
 511         call->in.data = buf;
 512         call->in.length = len;
 513
 514         DEBUG(10,("Received krb5 UDP packet of length %lu from %s\n",
 515                  (long)call->in.length,
 516                  tsocket_address_string(call->src, call)));
 517
 518         /* Call krb5 */
 519         ret = sock->kdc_socket->process(sock->kdc_socket->kdc,
 520                                        call,
 521                                        &call->in,
 522                                        &call->out,
 523                                        call->src,
 524                                        sock->kdc_socket->local_address,
 525                                        1 /* Datagram */);
 526         if (ret == KDC_PROCESS_FAILED) {
 527                 talloc_free(call);
 528                 goto done;
 529         }
 530
 531         if (ret == KDC_PROCESS_PROXY) {
 532                 uint16_t port;
 533
 534                 if (!sock->kdc_socket->kdc->am_rodc) {
 535                         DEBUG(0,("kdc_udp_call_loop: proxying requested when not RODC"));
 536                         talloc_free(call);
 537                         goto done;
 538                 }
 539
 540                 port = tsocket_address_inet_port(sock->kdc_socket->local_address);
 541
 542                 subreq = kdc_udp_proxy_send(call,
 543                                             sock->kdc_socket->kdc->task->event_ctx,
 544                                             sock->kdc_socket->kdc,
 545                                             port,
 546                                             call->in);
 547                 if (subreq == NULL) {
 548                         talloc_free(call);
 549                         goto done;
 550                 }
 551                 tevent_req_set_callback(subreq, kdc_udp_call_proxy_done, call);
 552                 goto done;
 553         }
 554
 555         subreq = tdgram_sendto_queue_send(call,
 556                                           sock->kdc_socket->kdc->task->event_ctx,
 557                                           sock->dgram,
 558                                           sock->send_queue,
 559                                           call->out.data,
 560                                           call->out.length,
 561                                           call->src);
 562         if (subreq == NULL) {
 563                 talloc_free(call);
 564                 goto done;
 565         }
 566         tevent_req_set_callback(subreq, kdc_udp_call_sendto_done, call);
 567
 568 done:
 569         subreq = tdgram_recvfrom_send(sock,
 570                                       sock->kdc_socket->kdc->task->event_ctx,
 571                                       sock->dgram);
 572         if (subreq == NULL) {
 573                 task_server_terminate(sock->kdc_socket->kdc->task,
 574                                       "no memory for tdgram_recvfrom_send",
 575                                       true);
 576                 return;
 577         }
 578         tevent_req_set_callback(subreq, kdc_udp_call_loop, sock);
 579 }
 580
 581 static void kdc_udp_call_proxy_done(struct tevent_req *subreq)
 582 {
 583         struct kdc_udp_call *call =
 584                 tevent_req_callback_data(subreq,
 585                 struct kdc_udp_call);
 586         NTSTATUS status;
 587
 588         status = kdc_udp_proxy_recv(subreq, call, &call->out);
 589         TALLOC_FREE(subreq);
 590         if (!NT_STATUS_IS_OK(status)) {
 591                 /* generate an error packet */
 592                 status = kdc_proxy_unavailable_error(call->sock->kdc_socket->kdc,
 593                                                      call, &call->out);
 594         }
 595
 596         if (!NT_STATUS_IS_OK(status)) {
 597                 talloc_free(call);
 598                 return;
 599         }
 600
 601         subreq = tdgram_sendto_queue_send(call,
 602                                           call->sock->kdc_socket->kdc->task->event_ctx,
 603                                           call->sock->dgram,
 604                                           call->sock->send_queue,
 605                                           call->out.data,
 606                                           call->out.length,
 607                                           call->src);
 608         if (subreq == NULL) {
 609                 talloc_free(call);
 610                 return;
 611         }
 612
 613         tevent_req_set_callback(subreq, kdc_udp_call_sendto_done, call);
 614 }
 615
 616 static void kdc_udp_call_sendto_done(struct tevent_req *subreq)
 617 {
 618         struct kdc_udp_call *call = tevent_req_callback_data(subreq,
 619                                        struct kdc_udp_call);
 620         ssize_t ret;
 621         int sys_errno;
 622
 623         ret = tdgram_sendto_queue_recv(subreq, &sys_errno);
 624
 625         /* We don't care about errors */
 626
 627         talloc_free(call);
 628 }
 629
 630 /*
 631   start listening on the given address
 632 */
 633 static NTSTATUS kdc_add_socket(struct kdc_server *kdc,
 634                                const struct model_ops *model_ops,
 635                                const char *name,
 636                                const char *address,
 637                                uint16_t port,
 638                                kdc_process_fn_t process,
 639                                bool udp_only)
 640 {
 641         struct kdc_socket *kdc_socket;
 642         struct kdc_udp_socket *kdc_udp_socket;
 643         struct tevent_req *udpsubreq;
 644         NTSTATUS status;
 645         int ret;
 646
 647         kdc_socket = talloc(kdc, struct kdc_socket);
 648         NT_STATUS_HAVE_NO_MEMORY(kdc_socket);
 649
 650         kdc_socket->kdc = kdc;
 651         kdc_socket->process = process;
 652
 653         ret = tsocket_address_inet_from_strings(kdc_socket, "ip",
 654                                                 address, port,
 655                                                 &kdc_socket->local_address);
 656         if (ret != 0) {
 657                 status = map_nt_error_from_unix_common(errno);
 658                 return status;
 659         }
 660
 661         if (!udp_only) {
 662                 status = stream_setup_socket(kdc->task,
 663                                              kdc->task->event_ctx,
 664                                              kdc->task->lp_ctx,
 665                                              model_ops,
 666                                              &kdc_tcp_stream_ops,
 667                                              "ip", address, &port,
 668                                              lpcfg_socket_options(kdc->task->lp_ctx),
 669                                              kdc_socket);
 670                 if (!NT_STATUS_IS_OK(status)) {
 671                         DEBUG(0,("Failed to bind to %s:%u TCP - %s\n",
 672                                  address, port, nt_errstr(status)));
 673                         talloc_free(kdc_socket);
 674                         return status;
 675                 }
 676         }
 677
 678         kdc_udp_socket = talloc(kdc_socket, struct kdc_udp_socket);
 679         NT_STATUS_HAVE_NO_MEMORY(kdc_udp_socket);
 680
 681         kdc_udp_socket->kdc_socket = kdc_socket;
 682
 683         ret = tdgram_inet_udp_socket(kdc_socket->local_address,
 684                                      NULL,
 685                                      kdc_udp_socket,
 686                                      &kdc_udp_socket->dgram);
 687         if (ret != 0) {
 688                 status = map_nt_error_from_unix_common(errno);
 689                 DEBUG(0,("Failed to bind to %s:%u UDP - %s\n",
 690                          address, port, nt_errstr(status)));
 691                 return status;
 692         }
 693
 694         kdc_udp_socket->send_queue = tevent_queue_create(kdc_udp_socket,
 695                                                          "kdc_udp_send_queue");
 696         NT_STATUS_HAVE_NO_MEMORY(kdc_udp_socket->send_queue);
 697
 698         udpsubreq = tdgram_recvfrom_send(kdc_udp_socket,
 699                                          kdc->task->event_ctx,
 700                                          kdc_udp_socket->dgram);
 701         NT_STATUS_HAVE_NO_MEMORY(udpsubreq);
 702         tevent_req_set_callback(udpsubreq, kdc_udp_call_loop, kdc_udp_socket);
 703
 704         return NT_STATUS_OK;
 705 }
 706
 707
 708 /*
 709   setup our listening sockets on the configured network interfaces
 710 */
 711 static NTSTATUS kdc_startup_interfaces(struct kdc_server *kdc, struct loadparm_context *lp_ctx,
 712                                        struct interface *ifaces)
 713 {
 714         const struct model_ops *model_ops;
 715         int num_interfaces;
 716         TALLOC_CTX *tmp_ctx = talloc_new(kdc);
 717         NTSTATUS status;
 718         int i;
 719         uint16_t kdc_port = lpcfg_krb5_port(lp_ctx);
 720         uint16_t kpasswd_port = lpcfg_kpasswd_port(lp_ctx);
 721         bool done_wildcard = false;
 722
 723         /* within the kdc task we want to be a single process, so
 724            ask for the single process model ops and pass these to the
 725            stream_setup_socket() call. */
 726         model_ops = process_model_startup("single");
 727         if (!model_ops) {
 728                 DEBUG(0,("Can't find 'single' process model_ops\n"));
 729                 return NT_STATUS_INTERNAL_ERROR;
 730         }
 731
 732         num_interfaces = iface_list_count(ifaces);
 733
 734         /* if we are allowing incoming packets from any address, then
 735            we need to bind to the wildcard address */
 736         if (!lpcfg_bind_interfaces_only(lp_ctx)) {
 737                 const char **wcard = iface_list_wildcard(kdc, lp_ctx);
 738                 NT_STATUS_HAVE_NO_MEMORY(wcard);
 739                 for (i=0; wcard[i]; i++) {
 740                         if (kdc_port) {
 741                                 status = kdc_add_socket(kdc, model_ops,
 742                                                         "kdc", wcard[i], kdc_port,
 743                                                         kdc_process, false);
 744                                 NT_STATUS_NOT_OK_RETURN(status);
 745                         }
 746
 747                         if (kpasswd_port) {
 748                                 status = kdc_add_socket(kdc, model_ops,
 749                                                         "kpasswd", wcard[i], kpasswd_port,
 750                                                         kpasswdd_process, false);
 751                                 NT_STATUS_NOT_OK_RETURN(status);
 752                         }
 753                 }
 754                 talloc_free(wcard);
 755                 done_wildcard = true;
 756         }
 757
 758         for (i=0; i<num_interfaces; i++) {
 759                 const char *address = talloc_strdup(tmp_ctx, iface_list_n_ip(ifaces, i));
 760
 761                 if (kdc_port) {
 762                         status = kdc_add_socket(kdc, model_ops,
 763                                                 "kdc", address, kdc_port,
 764                                                 kdc_process, done_wildcard);
 765                         NT_STATUS_NOT_OK_RETURN(status);
 766                 }
 767
 768                 if (kpasswd_port) {
 769                         status = kdc_add_socket(kdc, model_ops,
 770                                                 "kpasswd", address, kpasswd_port,
 771                                                 kpasswdd_process, done_wildcard);
 772                         NT_STATUS_NOT_OK_RETURN(status);
 773                 }
 774         }
 775
 776         talloc_free(tmp_ctx);
 777
 778         return NT_STATUS_OK;
 779 }
 780
 781
 782 static NTSTATUS kdc_check_generic_kerberos(struct irpc_message *msg,
 783                                  struct kdc_check_generic_kerberos *r)
 784 {
 785         struct PAC_Validate pac_validate;
 786         DATA_BLOB srv_sig;
 787         struct PAC_SIGNATURE_DATA kdc_sig;
 788         struct kdc_server *kdc = talloc_get_type(msg->private_data, struct kdc_server);
 789         enum ndr_err_code ndr_err;
 790         krb5_enctype etype;
 791         int ret;
 792         hdb_entry_ex ent;
 793         krb5_principal principal;
 794         krb5_keyblock keyblock;
 795         Key *key;
 796
 797         /* There is no reply to this request */
 798         r->out.generic_reply = data_blob(NULL, 0);
 799
 800         ndr_err = ndr_pull_struct_blob(&r->in.generic_request, msg, &pac_validate,
 801                                        (ndr_pull_flags_fn_t)ndr_pull_PAC_Validate);
 802         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 803                 return NT_STATUS_INVALID_PARAMETER;
 804         }
 805
 806         if (pac_validate.MessageType != 3) {
 807                 /* We don't implement any other message types - such as certificate validation - yet */
 808                 return NT_STATUS_INVALID_PARAMETER;
 809         }
 810
 811         if (pac_validate.ChecksumAndSignature.length != (pac_validate.ChecksumLength + pac_validate.SignatureLength)
 812             || pac_validate.ChecksumAndSignature.length < pac_validate.ChecksumLength
 813             || pac_validate.ChecksumAndSignature.length < pac_validate.SignatureLength ) {
 814                 return NT_STATUS_INVALID_PARAMETER;
 815         }
 816
 817         srv_sig = data_blob_const(pac_validate.ChecksumAndSignature.data,
 818                                   pac_validate.ChecksumLength);
 819
 820         if (pac_validate.SignatureType == CKSUMTYPE_HMAC_MD5) {
 821                 etype = ETYPE_ARCFOUR_HMAC_MD5;
 822         } else {
 823                 ret = krb5_cksumtype_to_enctype(kdc->smb_krb5_context->krb5_context, pac_validate.SignatureType,
 824                                                 &etype);
 825                 if (ret != 0) {
 826                         return NT_STATUS_LOGON_FAILURE;
 827                 }
 828         }
 829
 830         ret = krb5_make_principal(kdc->smb_krb5_context->krb5_context, &principal,
 831                                   lpcfg_realm(kdc->task->lp_ctx),
 832                                   "krbtgt", lpcfg_realm(kdc->task->lp_ctx),
 833                                   NULL);
 834
 835         if (ret != 0) {
 836                 return NT_STATUS_NO_MEMORY;
 837         }
 838
 839         ret = kdc->config->db[0]->hdb_fetch_kvno(kdc->smb_krb5_context->krb5_context,
 840                                                  kdc->config->db[0],
 841                                                  principal,
 842                                                  HDB_F_GET_KRBTGT | HDB_F_DECRYPT,
 843                                                  0,
 844                                                  &ent);
 845
 846         if (ret != 0) {
 847                 hdb_free_entry(kdc->smb_krb5_context->krb5_context, &ent);
 848                 krb5_free_principal(kdc->smb_krb5_context->krb5_context, principal);
 849
 850                 return NT_STATUS_LOGON_FAILURE;
 851         }
 852
 853         ret = hdb_enctype2key(kdc->smb_krb5_context->krb5_context, &ent.entry, etype, &key);
 854
 855         if (ret != 0) {
 856                 hdb_free_entry(kdc->smb_krb5_context->krb5_context, &ent);
 857                 krb5_free_principal(kdc->smb_krb5_context->krb5_context, principal);
 858                 return NT_STATUS_LOGON_FAILURE;
 859         }
 860
 861         keyblock = key->key;
 862
 863         kdc_sig.type = pac_validate.SignatureType;
 864         kdc_sig.signature = data_blob_const(&pac_validate.ChecksumAndSignature.data[pac_validate.ChecksumLength],
 865                                             pac_validate.SignatureLength);
 866         ret = check_pac_checksum(msg, srv_sig, &kdc_sig,
 867                            kdc->smb_krb5_context->krb5_context, &keyblock);
 868
 869         hdb_free_entry(kdc->smb_krb5_context->krb5_context, &ent);
 870         krb5_free_principal(kdc->smb_krb5_context->krb5_context, principal);
 871
 872         if (ret != 0) {
 873                 return NT_STATUS_LOGON_FAILURE;
 874         }
 875
 876         return NT_STATUS_OK;
 877 }
 878
 879
 880 /*
 881   startup the kdc task
 882 */
 883 static void kdc_task_init(struct task_server *task)
 884 {
 885         struct kdc_server *kdc;
 886         NTSTATUS status;
 887         krb5_error_code ret;
 888         struct interface *ifaces;
 889         int ldb_ret;
 890
 891         switch (lpcfg_server_role(task->lp_ctx)) {
 892         case ROLE_STANDALONE:
 893                 task_server_terminate(task, "kdc: no KDC required in standalone configuration", false);
 894                 return;
 895         case ROLE_DOMAIN_MEMBER:
 896                 task_server_terminate(task, "kdc: no KDC required in member server configuration", false);
 897                 return;
 898         case ROLE_DOMAIN_CONTROLLER:
 899                 /* Yes, we want a KDC */
 900                 break;
 901         }
 902
 903         load_interface_list(task, task->lp_ctx, &ifaces);
 904
 905         if (iface_list_count(ifaces) == 0) {
 906                 task_server_terminate(task, "kdc: no network interfaces configured", false);
 907                 return;
 908         }
 909
 910         task_server_set_title(task, "task[kdc]");
 911
 912         kdc = talloc_zero(task, struct kdc_server);
 913         if (kdc == NULL) {
 914                 task_server_terminate(task, "kdc: out of memory", true);
 915                 return;
 916         }
 917
 918         kdc->task = task;
 919
 920
 921         /* get a samdb connection */
 922         kdc->samdb = samdb_connect(kdc, kdc->task->event_ctx, kdc->task->lp_ctx,
 923                                    system_session(kdc->task->lp_ctx), 0);
 924         if (!kdc->samdb) {
 925                 DEBUG(1,("kdc_task_init: unable to connect to samdb\n"));
 926                 task_server_terminate(task, "kdc: krb5_init_context samdb connect failed", true);
 927                 return;
 928         }
 929
 930         ldb_ret = samdb_rodc(kdc->samdb, &kdc->am_rodc);
 931         if (ldb_ret != LDB_SUCCESS) {
 932                 DEBUG(1, ("kdc_task_init: Cannot determine if we are an RODC: %s\n",
 933                           ldb_errstring(kdc->samdb)));
 934                 task_server_terminate(task, "kdc: krb5_init_context samdb RODC connect failed", true);
 935                 return;
 936         }
 937
 938         kdc->proxy_timeout = lpcfg_parm_int(kdc->task->lp_ctx, NULL, "kdc", "proxy timeout", 5);
 939
 940         initialize_krb5_error_table();
 941
 942         ret = smb_krb5_init_context(kdc, task->event_ctx, task->lp_ctx, &kdc->smb_krb5_context);
 943         if (ret) {
 944                 DEBUG(1,("kdc_task_init: krb5_init_context failed (%s)\n",
 945                          error_message(ret)));
 946                 task_server_terminate(task, "kdc: krb5_init_context failed", true);
 947                 return;
 948         }
 949
 950         krb5_add_et_list(kdc->smb_krb5_context->krb5_context, initialize_hdb_error_table_r);
 951
 952         ret = krb5_kdc_get_config(kdc->smb_krb5_context->krb5_context,
 953                                   &kdc->config);
 954         if(ret) {
 955                 task_server_terminate(task, "kdc: failed to get KDC configuration", true);
 956                 return;
 957         }
 958
 959         kdc->config->logf = kdc->smb_krb5_context->logf;
 960         kdc->config->db = talloc(kdc, struct HDB *);
 961         if (!kdc->config->db) {
 962                 task_server_terminate(task, "kdc: out of memory", true);
 963                 return;
 964         }
 965         kdc->config->num_db = 1;
 966
 967         /* Register hdb-samba4 hooks for use as a keytab */
 968
 969         kdc->base_ctx = talloc_zero(kdc, struct samba_kdc_base_context);
 970         if (!kdc->base_ctx) {
 971                 task_server_terminate(task, "kdc: out of memory", true);
 972                 return;
 973         }
 974
 975         kdc->base_ctx->ev_ctx = task->event_ctx;
 976         kdc->base_ctx->lp_ctx = task->lp_ctx;
 977
 978         status = hdb_samba4_create_kdc(kdc->base_ctx,
 979                                        kdc->smb_krb5_context->krb5_context,
 980                                        &kdc->config->db[0]);
 981         if (!NT_STATUS_IS_OK(status)) {
 982                 task_server_terminate(task, "kdc: hdb_samba4_create_kdc (setup KDC database) failed", true);
 983                 return;
 984         }
 985
 986         ret = krb5_plugin_register(kdc->smb_krb5_context->krb5_context,
 987                                    PLUGIN_TYPE_DATA, "hdb",
 988                                    &hdb_samba4);
 989         if(ret) {
 990                 task_server_terminate(task, "kdc: failed to register hdb plugin", true);
 991                 return;
 992         }
 993
 994         ret = krb5_kt_register(kdc->smb_krb5_context->krb5_context, &hdb_kt_ops);
 995         if(ret) {
 996                 task_server_terminate(task, "kdc: failed to register keytab plugin", true);
 997                 return;
 998         }
 999
1000         /* Register WinDC hooks */
1001         ret = krb5_plugin_register(kdc->smb_krb5_context->krb5_context,
1002                                    PLUGIN_TYPE_DATA, "windc",
1003                                    &windc_plugin_table);
1004         if(ret) {
1005                 task_server_terminate(task, "kdc: failed to register windc plugin", true);
1006                 return;
1007         }
1008
1009         ret = krb5_kdc_windc_init(kdc->smb_krb5_context->krb5_context);
1010
1011         if(ret) {
1012                 task_server_terminate(task, "kdc: failed to init windc plugin", true);
1013                 return;
1014         }
1015
1016         ret = krb5_kdc_pkinit_config(kdc->smb_krb5_context->krb5_context, kdc->config);
1017
1018         if(ret) {
1019                 task_server_terminate(task, "kdc: failed to init kdc pkinit subsystem", true);
1020                 return;
1021         }
1022
1023         /* start listening on the configured network interfaces */
1024         status = kdc_startup_interfaces(kdc, task->lp_ctx, ifaces);
1025         if (!NT_STATUS_IS_OK(status)) {
1026                 task_server_terminate(task, "kdc failed to setup interfaces", true);
1027                 return;
1028         }
1029
1030         status = IRPC_REGISTER(task->msg_ctx, irpc, KDC_CHECK_GENERIC_KERBEROS,
1031                                kdc_check_generic_kerberos, kdc);
1032         if (!NT_STATUS_IS_OK(status)) {
1033                 task_server_terminate(task, "kdc failed to setup monitoring", true);
1034                 return;
1035         }
1036
1037         irpc_add_name(task->msg_ctx, "kdc_server");
1038 }
1039
1040
1041 /* called at smbd startup - register ourselves as a server service */
1042 NTSTATUS server_service_kdc_init(void)
1043 {
1044         return register_server_service("kdc", kdc_task_init);
1045 }