r15356: Remove unused 'flags' argument from socket_send() and friends.
[bbaumbach/samba-autobuild/.git] / 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
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 2 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, write to the Free Software
22    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23 */
24
25 #include "includes.h"
26 #include "smbd/service_task.h"
27 #include "smbd/service.h"
28 #include "smbd/service_stream.h"
29 #include "smbd/process_model.h"
30 #include "lib/events/events.h"
31 #include "lib/socket/socket.h"
32 #include "kdc/kdc.h"
33 #include "system/network.h"
34 #include "dlinklist.h"
35 #include "lib/messaging/irpc.h"
36 #include "lib/stream/packet.h"
37 #include "librpc/gen_ndr/samr.h"
38 #include "netif/netif.h"
39
40 /* hold all the info needed to send a reply */
41 struct kdc_reply {
42         struct kdc_reply *next, *prev;
43         struct socket_address *dest;
44         DATA_BLOB packet;
45 };
46
47 typedef BOOL (*kdc_process_fn_t)(struct kdc_server *kdc,
48                                  TALLOC_CTX *mem_ctx, 
49                                  DATA_BLOB *input, 
50                                  DATA_BLOB *reply,
51                                  struct socket_address *peer_addr, 
52                                  struct socket_address *my_addr);
53
54 /* hold information about one kdc socket */
55 struct kdc_socket {
56         struct socket_context *sock;
57         struct kdc_server *kdc;
58         struct fd_event *fde;
59
60         /* a queue of outgoing replies that have been deferred */
61         struct kdc_reply *send_queue;
62
63         kdc_process_fn_t process;
64 };
65 /*
66   state of an open tcp connection
67 */
68 struct kdc_tcp_connection {
69         /* stream connection we belong to */
70         struct stream_connection *conn;
71
72         /* the kdc_server the connection belongs to */
73         struct kdc_server *kdc;
74
75         struct packet_context *packet;
76
77         kdc_process_fn_t process;
78 };
79
80 /*
81   handle fd send events on a KDC socket
82 */
83 static void kdc_send_handler(struct kdc_socket *kdc_socket)
84 {
85         while (kdc_socket->send_queue) {
86                 struct kdc_reply *rep = kdc_socket->send_queue;
87                 NTSTATUS status;
88                 size_t sendlen;
89
90                 status = socket_sendto(kdc_socket->sock, &rep->packet, &sendlen,
91                                        rep->dest);
92                 if (NT_STATUS_EQUAL(status, STATUS_MORE_ENTRIES)) {
93                         break;
94                 }
95                 if (NT_STATUS_EQUAL(status, NT_STATUS_INVALID_BUFFER_SIZE)) {
96                         /* Replace with a krb err, response to big */
97                 }
98                 
99                 DLIST_REMOVE(kdc_socket->send_queue, rep);
100                 talloc_free(rep);
101         }
102
103         if (kdc_socket->send_queue == NULL) {
104                 EVENT_FD_NOT_WRITEABLE(kdc_socket->fde);
105         }
106 }
107
108
109 /*
110   handle fd recv events on a KDC socket
111 */
112 static void kdc_recv_handler(struct kdc_socket *kdc_socket)
113 {
114         NTSTATUS status;
115         TALLOC_CTX *tmp_ctx = talloc_new(kdc_socket);
116         DATA_BLOB blob;
117         struct kdc_reply *rep;
118         DATA_BLOB reply;
119         size_t nread, dsize;
120         struct socket_address *src;
121         struct socket_address *my_addr;
122         int ret;
123
124         status = socket_pending(kdc_socket->sock, &dsize);
125         if (!NT_STATUS_IS_OK(status)) {
126                 talloc_free(tmp_ctx);
127                 return;
128         }
129
130         blob = data_blob_talloc(kdc_socket, NULL, dsize);
131         if (blob.data == NULL) {
132                 /* hope this is a temporary low memory condition */
133                 talloc_free(tmp_ctx);
134                 return;
135         }
136
137         status = socket_recvfrom(kdc_socket->sock, blob.data, blob.length, &nread,
138                                  tmp_ctx, &src);
139         if (!NT_STATUS_IS_OK(status)) {
140                 talloc_free(tmp_ctx);
141                 return;
142         }
143         blob.length = nread;
144         
145         DEBUG(10,("Received krb5 UDP packet of length %lu from %s:%u\n", 
146                  (long)blob.length, src->addr, (uint16_t)src->port));
147         
148         my_addr = socket_get_my_addr(kdc_socket->sock, tmp_ctx);
149         if (!my_addr) {
150                 talloc_free(tmp_ctx);
151                 return;
152         }
153
154
155         /* Call krb5 */
156         ret = kdc_socket->process(kdc_socket->kdc, 
157                                   tmp_ctx, 
158                                   &blob,  
159                                   &reply,
160                                   src, my_addr);
161         if (!ret) {
162                 talloc_free(tmp_ctx);
163                 return;
164         }
165
166         /* queue a pending reply */
167         rep = talloc(kdc_socket, struct kdc_reply);
168         if (rep == NULL) {
169                 talloc_free(tmp_ctx);
170                 return;
171         }
172         rep->dest         = talloc_steal(rep, src);
173         rep->packet       = reply;
174         talloc_steal(rep, reply.data);
175
176         if (rep->packet.data == NULL) {
177                 talloc_free(rep);
178                 talloc_free(tmp_ctx);
179                 return;
180         }
181
182         DLIST_ADD_END(kdc_socket->send_queue, rep, struct kdc_reply *);
183         EVENT_FD_WRITEABLE(kdc_socket->fde);
184         talloc_free(tmp_ctx);
185 }
186
187 /*
188   handle fd events on a KDC socket
189 */
190 static void kdc_socket_handler(struct event_context *ev, struct fd_event *fde,
191                                uint16_t flags, void *private)
192 {
193         struct kdc_socket *kdc_socket = talloc_get_type(private, struct kdc_socket);
194         if (flags & EVENT_FD_WRITE) {
195                 kdc_send_handler(kdc_socket);
196         } 
197         if (flags & EVENT_FD_READ) {
198                 kdc_recv_handler(kdc_socket);
199         }
200 }
201
202 static void kdc_tcp_terminate_connection(struct kdc_tcp_connection *kdcconn, const char *reason)
203 {
204         stream_terminate_connection(kdcconn->conn, reason);
205 }
206
207 /*
208   receive a full packet on a KDC connection
209 */
210 static NTSTATUS kdc_tcp_recv(void *private, DATA_BLOB blob)
211 {
212         struct kdc_tcp_connection *kdcconn = talloc_get_type(private, 
213                                                              struct kdc_tcp_connection);
214         NTSTATUS status = NT_STATUS_UNSUCCESSFUL;
215         TALLOC_CTX *tmp_ctx = talloc_new(kdcconn);
216         int ret;
217         DATA_BLOB input, reply;
218         struct socket_address *src_addr;
219         struct socket_address *my_addr;
220
221         talloc_steal(tmp_ctx, blob.data);
222
223         src_addr = socket_get_peer_addr(kdcconn->conn->socket, tmp_ctx);
224         if (!src_addr) {
225                 talloc_free(tmp_ctx);
226                 return NT_STATUS_NO_MEMORY;
227         }
228
229         my_addr = socket_get_my_addr(kdcconn->conn->socket, tmp_ctx);
230         if (!my_addr) {
231                 talloc_free(tmp_ctx);
232                 return NT_STATUS_NO_MEMORY;
233         }
234
235         /* Call krb5 */
236         input = data_blob_const(blob.data + 4, blob.length - 4); 
237
238         ret = kdcconn->process(kdcconn->kdc, 
239                                tmp_ctx,
240                                &input,
241                                &reply,
242                                src_addr,
243                                my_addr);
244         if (!ret) {
245                 talloc_free(tmp_ctx);
246                 return NT_STATUS_INTERNAL_ERROR;
247         }
248
249         /* and now encode the reply */
250         blob = data_blob_talloc(kdcconn, NULL, reply.length + 4);
251         if (!blob.data) {
252                 talloc_free(tmp_ctx);
253                 return NT_STATUS_NO_MEMORY;
254         }
255
256         RSIVAL(blob.data, 0, reply.length);
257         memcpy(blob.data + 4, reply.data, reply.length);        
258
259         status = packet_send(kdcconn->packet, blob);
260         if (!NT_STATUS_IS_OK(status)) {
261                 talloc_free(tmp_ctx);
262                 return status;
263         }
264
265         /* the call isn't needed any more */
266         talloc_free(tmp_ctx);
267         return NT_STATUS_OK;
268 }
269
270 /*
271   receive some data on a KDC connection
272 */
273 static void kdc_tcp_recv_handler(struct stream_connection *conn, uint16_t flags)
274 {
275         struct kdc_tcp_connection *kdcconn = talloc_get_type(conn->private, 
276                                                              struct kdc_tcp_connection);
277         packet_recv(kdcconn->packet);
278 }
279
280 /*
281   called on a tcp recv error
282 */
283 static void kdc_tcp_recv_error(void *private, NTSTATUS status)
284 {
285         struct kdc_tcp_connection *kdcconn = talloc_get_type(private, struct kdc_tcp_connection);
286         kdc_tcp_terminate_connection(kdcconn, nt_errstr(status));
287 }
288
289 /*
290   called when we can write to a connection
291 */
292 static void kdc_tcp_send(struct stream_connection *conn, uint16_t flags)
293 {
294         struct kdc_tcp_connection *kdcconn = talloc_get_type(conn->private, 
295                                                              struct kdc_tcp_connection);
296         packet_queue_run(kdcconn->packet);
297 }
298
299 /**
300    Wrapper for krb5_kdc_process_krb5_request, converting to/from Samba
301    calling conventions
302 */
303
304 static BOOL kdc_process(struct kdc_server *kdc,
305                         TALLOC_CTX *mem_ctx, 
306                         DATA_BLOB *input, 
307                         DATA_BLOB *reply,
308                         struct socket_address *peer_addr, 
309                         struct socket_address *my_addr)
310 {
311         int ret;        
312         krb5_data k5_reply;
313
314         DEBUG(10,("Received KDC packet of length %lu from %s:%d\n", 
315                   (long)input->length - 4, peer_addr->addr, peer_addr->port));
316
317         ret = krb5_kdc_process_krb5_request(kdc->smb_krb5_context->krb5_context, 
318                                             kdc->config,
319                                             input->data, input->length,
320                                             &k5_reply,
321                                             peer_addr->addr,
322                                             peer_addr->sockaddr);
323         if (ret == -1) {
324                 *reply = data_blob(NULL, 0);
325                 return False;
326         }
327         *reply = data_blob_talloc(mem_ctx, k5_reply.data, k5_reply.length);
328         krb5_data_free(&k5_reply);
329         return True;
330 }
331
332 /*
333   called when we get a new connection
334 */
335 static void kdc_tcp_generic_accept(struct stream_connection *conn, kdc_process_fn_t process_fn)
336 {
337         struct kdc_server *kdc = talloc_get_type(conn->private, struct kdc_server);
338         struct kdc_tcp_connection *kdcconn;
339
340         kdcconn = talloc_zero(conn, struct kdc_tcp_connection);
341         if (!kdcconn) {
342                 stream_terminate_connection(conn, "kdc_tcp_accept: out of memory");
343                 return;
344         }
345         kdcconn->conn    = conn;
346         kdcconn->kdc     = kdc;
347         kdcconn->process = process_fn;
348         conn->private    = kdcconn;
349
350         kdcconn->packet = packet_init(kdcconn);
351         if (kdcconn->packet == NULL) {
352                 kdc_tcp_terminate_connection(kdcconn, "kdc_tcp_accept: out of memory");
353                 return;
354         }
355         packet_set_private(kdcconn->packet, kdcconn);
356         packet_set_socket(kdcconn->packet, conn->socket);
357         packet_set_callback(kdcconn->packet, kdc_tcp_recv);
358         packet_set_full_request(kdcconn->packet, packet_full_request_u32);
359         packet_set_error_handler(kdcconn->packet, kdc_tcp_recv_error);
360         packet_set_event_context(kdcconn->packet, conn->event.ctx);
361         packet_set_fde(kdcconn->packet, conn->event.fde);
362         packet_set_serialise(kdcconn->packet);
363 }
364
365 static void kdc_tcp_accept(struct stream_connection *conn)
366 {
367         kdc_tcp_generic_accept(conn, kdc_process);
368 }
369
370 static const struct stream_server_ops kdc_tcp_stream_ops = {
371         .name                   = "kdc_tcp",
372         .accept_connection      = kdc_tcp_accept,
373         .recv_handler           = kdc_tcp_recv_handler,
374         .send_handler           = kdc_tcp_send
375 };
376
377 static void kpasswdd_tcp_accept(struct stream_connection *conn)
378 {
379         kdc_tcp_generic_accept(conn, kpasswdd_process);
380 }
381
382 static const struct stream_server_ops kpasswdd_tcp_stream_ops = {
383         .name                   = "kpasswdd_tcp",
384         .accept_connection      = kpasswdd_tcp_accept,
385         .recv_handler           = kdc_tcp_recv_handler,
386         .send_handler           = kdc_tcp_send
387 };
388
389 /*
390   start listening on the given address
391 */
392 static NTSTATUS kdc_add_socket(struct kdc_server *kdc, const char *address)
393 {
394         const struct model_ops *model_ops;
395         struct kdc_socket *kdc_socket;
396         struct kdc_socket *kpasswd_socket;
397         struct socket_address *kdc_address, *kpasswd_address;
398         NTSTATUS status;
399         uint16_t kdc_port = lp_krb5_port();
400         uint16_t kpasswd_port = lp_kpasswd_port();
401
402         kdc_socket = talloc(kdc, struct kdc_socket);
403         NT_STATUS_HAVE_NO_MEMORY(kdc_socket);
404
405         kpasswd_socket = talloc(kdc, struct kdc_socket);
406         NT_STATUS_HAVE_NO_MEMORY(kpasswd_socket);
407
408         status = socket_create("ip", SOCKET_TYPE_DGRAM, &kdc_socket->sock, 0);
409         if (!NT_STATUS_IS_OK(status)) {
410                 talloc_free(kdc_socket);
411                 return status;
412         }
413
414         status = socket_create("ip", SOCKET_TYPE_DGRAM, &kpasswd_socket->sock, 0);
415         if (!NT_STATUS_IS_OK(status)) {
416                 talloc_free(kpasswd_socket);
417                 return status;
418         }
419
420         kdc_socket->kdc = kdc;
421         kdc_socket->send_queue = NULL;
422         kdc_socket->process = kdc_process;
423
424         talloc_steal(kdc_socket, kdc_socket->sock);
425
426         kdc_socket->fde = event_add_fd(kdc->task->event_ctx, kdc, 
427                                        socket_get_fd(kdc_socket->sock), EVENT_FD_READ,
428                                        kdc_socket_handler, kdc_socket);
429
430         kdc_address = socket_address_from_strings(kdc_socket, kdc_socket->sock->backend_name, 
431                                                   address, kdc_port);
432         NT_STATUS_HAVE_NO_MEMORY(kdc_address);
433
434         status = socket_listen(kdc_socket->sock, kdc_address, 0, 0);
435         if (!NT_STATUS_IS_OK(status)) {
436                 DEBUG(0,("Failed to bind to %s:%d UDP for kdc - %s\n", 
437                          address, kdc_port, nt_errstr(status)));
438                 talloc_free(kdc_socket);
439                 return status;
440         }
441
442         kpasswd_socket->kdc = kdc;
443         kpasswd_socket->send_queue = NULL;
444         kpasswd_socket->process = kpasswdd_process;
445
446         talloc_steal(kpasswd_socket, kpasswd_socket->sock);
447
448         kpasswd_socket->fde = event_add_fd(kdc->task->event_ctx, kdc, 
449                                            socket_get_fd(kpasswd_socket->sock), EVENT_FD_READ,
450                                            kdc_socket_handler, kpasswd_socket);
451         
452         kpasswd_address = socket_address_from_strings(kpasswd_socket, kpasswd_socket->sock->backend_name, 
453                                                       address, kpasswd_port);
454         NT_STATUS_HAVE_NO_MEMORY(kpasswd_address);
455
456         status = socket_listen(kpasswd_socket->sock, kpasswd_address, 0, 0);
457         if (!NT_STATUS_IS_OK(status)) {
458                 DEBUG(0,("Failed to bind to %s:%d UDP for kpasswd - %s\n", 
459                          address, kpasswd_port, nt_errstr(status)));
460                 talloc_free(kpasswd_socket);
461                 return status;
462         }
463
464         /* within the kdc task we want to be a single process, so
465            ask for the single process model ops and pass these to the
466            stream_setup_socket() call. */
467         model_ops = process_model_byname("single");
468         if (!model_ops) {
469                 DEBUG(0,("Can't find 'single' process model_ops\n"));
470                 talloc_free(kdc_socket);
471                 return NT_STATUS_INTERNAL_ERROR;
472         }
473
474         status = stream_setup_socket(kdc->task->event_ctx, model_ops, 
475                                      &kdc_tcp_stream_ops, 
476                                      "ip", address, &kdc_port, kdc);
477         if (!NT_STATUS_IS_OK(status)) {
478                 DEBUG(0,("Failed to bind to %s:%u TCP - %s\n",
479                          address, kdc_port, nt_errstr(status)));
480                 talloc_free(kdc_socket);
481                 return status;
482         }
483
484         status = stream_setup_socket(kdc->task->event_ctx, model_ops, 
485                                      &kpasswdd_tcp_stream_ops, 
486                                      "ip", address, &kpasswd_port, kdc);
487         if (!NT_STATUS_IS_OK(status)) {
488                 DEBUG(0,("Failed to bind to %s:%u TCP - %s\n",
489                          address, kpasswd_port, nt_errstr(status)));
490                 talloc_free(kdc_socket);
491                 return status;
492         }
493
494         return NT_STATUS_OK;
495 }
496
497
498 /*
499   setup our listening sockets on the configured network interfaces
500 */
501 static NTSTATUS kdc_startup_interfaces(struct kdc_server *kdc)
502 {
503         int num_interfaces = iface_count();
504         TALLOC_CTX *tmp_ctx = talloc_new(kdc);
505         NTSTATUS status;
506         
507         int i;
508         
509         for (i=0; i<num_interfaces; i++) {
510                 const char *address = talloc_strdup(tmp_ctx, iface_n_ip(i));
511                 status = kdc_add_socket(kdc, address);
512                 NT_STATUS_NOT_OK_RETURN(status);
513         }
514
515         talloc_free(tmp_ctx);
516
517         return NT_STATUS_OK;
518 }
519
520 /*
521   startup the kdc task
522 */
523 static void kdc_task_init(struct task_server *task)
524 {
525         struct kdc_server *kdc;
526         NTSTATUS status;
527         krb5_error_code ret;
528
529         switch (lp_server_role()) {
530         case ROLE_STANDALONE:
531                 task_server_terminate(task, "kdc: no KDC required in standalone configuration");
532                 return;
533         case ROLE_DOMAIN_MEMBER:
534                 task_server_terminate(task, "kdc: no KDC required in member server configuration");
535                 return;
536         case ROLE_DOMAIN_PDC:
537         case ROLE_DOMAIN_BDC:
538                 /* Yes, we want a KDC */
539                 break;
540         }
541
542         if (iface_count() == 0) {
543                 task_server_terminate(task, "kdc: no network interfaces configured");
544                 return;
545         }
546
547         task_server_set_title(task, "task[kdc]");
548
549         kdc = talloc(task, struct kdc_server);
550         if (kdc == NULL) {
551                 task_server_terminate(task, "kdc: out of memory");
552                 return;
553         }
554
555         kdc->task = task;
556
557         /* Setup the KDC configuration */
558         kdc->config = talloc(kdc, krb5_kdc_configuration);
559         if (!kdc->config) {
560                 task_server_terminate(task, "kdc: out of memory");
561                 return;
562         }
563         krb5_kdc_default_config(kdc->config);
564
565         initialize_krb5_error_table();
566
567         ret = smb_krb5_init_context(kdc, &kdc->smb_krb5_context);
568         if (ret) {
569                 DEBUG(1,("kdc_task_init: krb5_init_context failed (%s)\n", 
570                          error_message(ret)));
571                 task_server_terminate(task, "kdc: krb5_init_context failed");
572                 return; 
573         }
574
575         krb5_add_et_list(kdc->smb_krb5_context->krb5_context, initialize_hdb_error_table_r);
576
577         kdc->config->logf = kdc->smb_krb5_context->logf;
578         kdc->config->db = talloc(kdc->config, struct HDB *);
579         if (!kdc->config->db) {
580                 task_server_terminate(task, "kdc: out of memory");
581                 return;
582         }
583         kdc->config->num_db = 1;
584                 
585         status = kdc_hdb_ldb_create(kdc, kdc->smb_krb5_context->krb5_context, 
586                                     &kdc->config->db[0], NULL);
587         if (!NT_STATUS_IS_OK(status)) {
588                 task_server_terminate(task, "kdc: hdb_ldb_create (setup KDC database) failed");
589                 return; 
590         }
591
592         ret = krb5_kt_register(kdc->smb_krb5_context->krb5_context, &hdb_kt_ops);
593         if(ret) {
594                 task_server_terminate(task, "kdc: failed to register hdb keytab");
595                 return;
596         }
597         /* start listening on the configured network interfaces */
598         status = kdc_startup_interfaces(kdc);
599         if (!NT_STATUS_IS_OK(status)) {
600                 task_server_terminate(task, "kdc failed to setup interfaces");
601                 return;
602         }
603
604         irpc_add_name(task->msg_ctx, "kdc_server");
605 }
606
607
608 /*
609   called on startup of the KDC service 
610 */
611 static NTSTATUS kdc_init(struct event_context *event_ctx, 
612                          const struct model_ops *model_ops)
613 {       
614         return task_server_startup(event_ctx, model_ops, kdc_task_init);
615 }
616
617 /* called at smbd startup - register ourselves as a server service */
618 NTSTATUS server_service_kdc_init(void)
619 {
620         return register_server_service("kdc", kdc_init);
621 }