r23792: convert Samba4 to GPLv3
[kai/samba-autobuild/.git] / source4 / auth / kerberos / krb5_init_context.c
1 /* 
2    Unix SMB/CIFS implementation.
3    Wrapper for krb5_init_context
4
5    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2005
6    Copyright (C) Andrew Tridgell 2005
7    Copyright (C) Stefan Metzmacher 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 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 "includes.h"
24 #include "system/kerberos.h"
25 #include "heimdal/lib/krb5/krb5_locl.h"
26 #include "auth/kerberos/kerberos.h"
27 #include "lib/socket/socket.h"
28 #include "lib/stream/packet.h"
29 #include "system/network.h"
30 #include "lib/events/events.h"
31 #include "roken.h"
32
33 /*
34   context structure for operations on cldap packets
35 */
36 struct smb_krb5_socket {
37         struct socket_context *sock;
38
39         /* the fd event */
40         struct fd_event *fde;
41
42         NTSTATUS status;
43         DATA_BLOB request, reply;
44         
45         struct packet_context *packet;
46
47         size_t partial_read;
48
49         krb5_krbhst_info *hi;
50 };
51
52 static int smb_krb5_context_destroy_1(struct smb_krb5_context *ctx)
53 {
54         krb5_free_context(ctx->krb5_context); 
55         return 0;
56 }
57
58 static int smb_krb5_context_destroy_2(struct smb_krb5_context *ctx)
59 {
60         /* Otherwise krb5_free_context will try and close what we have already free()ed */
61         krb5_set_warn_dest(ctx->krb5_context, NULL);
62         krb5_closelog(ctx->krb5_context, ctx->logf);
63         smb_krb5_context_destroy_1(ctx);
64         return 0;
65 }
66
67 /* We never close down the DEBUG system, and no need to unreference the use */
68 static void smb_krb5_debug_close(void *private) {
69         return;
70 }
71
72 static void smb_krb5_debug_wrapper(const char *timestr, const char *msg, void *private) 
73 {
74         DEBUG(2, ("Kerberos: %s\n", msg));
75 }
76
77 /*
78   handle recv events on a smb_krb5 socket
79 */
80 static void smb_krb5_socket_recv(struct smb_krb5_socket *smb_krb5)
81 {
82         TALLOC_CTX *tmp_ctx = talloc_new(smb_krb5);
83         DATA_BLOB blob;
84         size_t nread, dsize;
85
86         smb_krb5->status = socket_pending(smb_krb5->sock, &dsize);
87         if (!NT_STATUS_IS_OK(smb_krb5->status)) {
88                 talloc_free(tmp_ctx);
89                 return;
90         }
91         
92         blob = data_blob_talloc(tmp_ctx, NULL, dsize);
93         if (blob.data == NULL && dsize != 0) {
94                 smb_krb5->status = NT_STATUS_NO_MEMORY;
95                 talloc_free(tmp_ctx);
96                 return;
97         }
98         
99         smb_krb5->status = socket_recv(smb_krb5->sock, blob.data, blob.length, &nread);
100         if (!NT_STATUS_IS_OK(smb_krb5->status)) {
101                 talloc_free(tmp_ctx);
102                 return;
103         }
104         blob.length = nread;
105         
106         if (nread == 0) {
107                 smb_krb5->status = NT_STATUS_UNEXPECTED_NETWORK_ERROR;
108                 talloc_free(tmp_ctx);
109                 return;
110         }
111         
112         DEBUG(2,("Received smb_krb5 packet of length %d\n", 
113                  (int)blob.length));
114         
115         talloc_steal(smb_krb5, blob.data);
116         smb_krb5->reply = blob;
117         talloc_free(tmp_ctx);
118 }
119
120 static NTSTATUS smb_krb5_full_packet(void *private, DATA_BLOB data) 
121 {
122         struct smb_krb5_socket *smb_krb5 = talloc_get_type(private, struct smb_krb5_socket);
123         talloc_steal(smb_krb5, data.data);
124         smb_krb5->reply = data;
125         smb_krb5->reply.length -= 4;
126         smb_krb5->reply.data += 4;
127         return NT_STATUS_OK;
128 }
129
130 /*
131   handle request timeouts
132 */
133 static void smb_krb5_request_timeout(struct event_context *event_ctx, 
134                                   struct timed_event *te, struct timeval t,
135                                   void *private)
136 {
137         struct smb_krb5_socket *smb_krb5 = talloc_get_type(private, struct smb_krb5_socket);
138         DEBUG(5,("Timed out smb_krb5 packet\n"));
139         smb_krb5->status = NT_STATUS_IO_TIMEOUT;
140 }
141
142 static void smb_krb5_error_handler(void *private, NTSTATUS status) 
143 {
144         struct smb_krb5_socket *smb_krb5 = talloc_get_type(private, struct smb_krb5_socket);
145         smb_krb5->status = status;
146 }
147
148 /*
149   handle send events on a smb_krb5 socket
150 */
151 static void smb_krb5_socket_send(struct smb_krb5_socket *smb_krb5)
152 {
153         NTSTATUS status;
154
155         size_t len;
156         
157         len = smb_krb5->request.length;
158         status = socket_send(smb_krb5->sock, &smb_krb5->request, &len);
159
160         if (!NT_STATUS_IS_OK(status)) return;
161         
162         EVENT_FD_READABLE(smb_krb5->fde);
163
164         EVENT_FD_NOT_WRITEABLE(smb_krb5->fde);
165         return;
166 }
167
168
169 /*
170   handle fd events on a smb_krb5_socket
171 */
172 static void smb_krb5_socket_handler(struct event_context *ev, struct fd_event *fde,
173                                  uint16_t flags, void *private)
174 {
175         struct smb_krb5_socket *smb_krb5 = talloc_get_type(private, struct smb_krb5_socket);
176         switch (smb_krb5->hi->proto) {
177         case KRB5_KRBHST_UDP:
178                 if (flags & EVENT_FD_READ) {
179                         smb_krb5_socket_recv(smb_krb5);
180                         return;
181                 }
182                 if (flags & EVENT_FD_WRITE) {
183                         smb_krb5_socket_send(smb_krb5);
184                         return;
185                 }
186                 /* not reached */
187                 return;
188         case KRB5_KRBHST_TCP:
189                 if (flags & EVENT_FD_READ) {
190                         packet_recv(smb_krb5->packet);
191                         return;
192                 }
193                 if (flags & EVENT_FD_WRITE) {
194                         packet_queue_run(smb_krb5->packet);
195                         return;
196                 }
197                 /* not reached */
198                 return;
199         case KRB5_KRBHST_HTTP:
200                 /* can't happen */
201                 break;
202         }
203 }
204
205
206 krb5_error_code smb_krb5_send_and_recv_func(krb5_context context,
207                                             void *data,
208                                             krb5_krbhst_info *hi,
209                                             const krb5_data *send_buf,
210                                             krb5_data *recv_buf)
211 {
212         krb5_error_code ret;
213         NTSTATUS status;
214         struct socket_address *remote_addr;
215         const char *name;
216         struct addrinfo *ai, *a;
217         struct smb_krb5_socket *smb_krb5;
218
219         struct event_context *ev = talloc_get_type(data, struct event_context);
220
221         DATA_BLOB send_blob = data_blob_const(send_buf->data, send_buf->length);
222
223         ret = krb5_krbhst_get_addrinfo(context, hi, &ai);
224         if (ret) {
225                 return ret;
226         }
227
228         for (a = ai; a; a = ai->ai_next) {
229                 smb_krb5 = talloc(NULL, struct smb_krb5_socket);
230                 if (!smb_krb5) {
231                         return ENOMEM;
232                 }
233                 smb_krb5->hi = hi;
234                 
235                 switch (a->ai_family) {
236                 case PF_INET:
237                         name = "ipv4";
238                         break;
239 #ifdef HAVE_IPV6
240                 case PF_INET6:
241                         name = "ipv6";
242                         break;
243 #endif
244                 default:
245                         talloc_free(smb_krb5);
246                         return EINVAL;
247                 }
248                 
249                 status = NT_STATUS_INVALID_PARAMETER;
250                 switch (hi->proto) {
251                 case KRB5_KRBHST_UDP:
252                         if (lp_parm_bool(-1, "krb5", "udp", True)) {
253                                 status = socket_create(name, SOCKET_TYPE_DGRAM, &smb_krb5->sock, 0);
254                         }
255                         break;
256                 case KRB5_KRBHST_TCP:
257                         if (lp_parm_bool(-1, "krb5", "tcp", True)) {
258                                 status = socket_create(name, SOCKET_TYPE_STREAM, &smb_krb5->sock, 0);
259                         }
260                         break;
261                 case KRB5_KRBHST_HTTP:
262                         talloc_free(smb_krb5);
263                         return EINVAL;
264                 }
265                 if (!NT_STATUS_IS_OK(status)) {
266                         talloc_free(smb_krb5);
267                         continue;
268                 }
269
270                 talloc_steal(smb_krb5, smb_krb5->sock);
271                 
272                 remote_addr = socket_address_from_sockaddr(smb_krb5, a->ai_addr, a->ai_addrlen); 
273                 if (!remote_addr) {
274                         talloc_free(smb_krb5);
275                         continue;
276                 }
277
278                 status = socket_connect_ev(smb_krb5->sock, NULL, remote_addr, 0, ev); 
279                 if (!NT_STATUS_IS_OK(status)) {
280                         talloc_free(smb_krb5);
281                         continue;
282                 }
283                 talloc_free(remote_addr);
284
285                 /* Setup the FDE, start listening for read events
286                  * from the start (otherwise we may miss a socket
287                  * drop) and mark as AUTOCLOSE along with the fde */
288
289                 /* Ths is equivilant to EVENT_FD_READABLE(smb_krb5->fde) */
290                 smb_krb5->fde = event_add_fd(ev, smb_krb5->sock, 
291                                              socket_get_fd(smb_krb5->sock), 
292                                              EVENT_FD_READ|EVENT_FD_AUTOCLOSE,
293                                              smb_krb5_socket_handler, smb_krb5);
294                 /* its now the job of the event layer to close the socket */
295                 socket_set_flags(smb_krb5->sock, SOCKET_FLAG_NOCLOSE);
296
297                 event_add_timed(ev, smb_krb5, 
298                                 timeval_current_ofs(context->kdc_timeout, 0),
299                                 smb_krb5_request_timeout, smb_krb5);
300
301                 
302                 smb_krb5->status = NT_STATUS_OK;
303                 smb_krb5->reply = data_blob(NULL, 0);
304
305                 switch (hi->proto) {
306                 case KRB5_KRBHST_UDP:
307                         EVENT_FD_WRITEABLE(smb_krb5->fde);
308                         smb_krb5->request = send_blob;
309                         break;
310                 case KRB5_KRBHST_TCP:
311
312                         smb_krb5->packet = packet_init(smb_krb5);
313                         if (smb_krb5->packet == NULL) {
314                                 talloc_free(smb_krb5);
315                                 return ENOMEM;
316                         }
317                         packet_set_private(smb_krb5->packet, smb_krb5);
318                         packet_set_socket(smb_krb5->packet, smb_krb5->sock);
319                         packet_set_callback(smb_krb5->packet, smb_krb5_full_packet);
320                         packet_set_full_request(smb_krb5->packet, packet_full_request_u32);
321                         packet_set_error_handler(smb_krb5->packet, smb_krb5_error_handler);
322                         packet_set_event_context(smb_krb5->packet, ev);
323                         packet_set_fde(smb_krb5->packet, smb_krb5->fde);
324
325                         smb_krb5->request = data_blob_talloc(smb_krb5, NULL, send_blob.length + 4);
326                         RSIVAL(smb_krb5->request.data, 0, send_blob.length);
327                         memcpy(smb_krb5->request.data+4, send_blob.data, send_blob.length);
328                         packet_send(smb_krb5->packet, smb_krb5->request);
329                         break;
330                 case KRB5_KRBHST_HTTP:
331                         talloc_free(smb_krb5);
332                         return EINVAL;
333                 }
334                 while ((NT_STATUS_IS_OK(smb_krb5->status)) && !smb_krb5->reply.length) {
335                         if (event_loop_once(ev) != 0) {
336                                 talloc_free(smb_krb5);
337                                 return EINVAL;
338                         }
339                 }
340                 if (NT_STATUS_EQUAL(smb_krb5->status, NT_STATUS_IO_TIMEOUT)) {
341                         talloc_free(smb_krb5);
342                         continue;
343                 }
344
345                 if (!NT_STATUS_IS_OK(smb_krb5->status)) {
346                         DEBUG(2,("Error reading smb_krb5 reply packet: %s\n", nt_errstr(smb_krb5->status)));
347                         talloc_free(smb_krb5);
348                         continue;
349                 }
350
351                 ret = krb5_data_copy(recv_buf, smb_krb5->reply.data, smb_krb5->reply.length);
352                 if (ret) {
353                         talloc_free(smb_krb5);
354                         return ret;
355                 }
356                 talloc_free(smb_krb5);
357                 
358                 break;
359         }
360         if (a) {
361                 return 0;
362         }
363         return KRB5_KDC_UNREACH;
364 }
365
366 krb5_error_code smb_krb5_init_context(void *parent_ctx, 
367                                       struct event_context *ev,
368                                        struct smb_krb5_context **smb_krb5_context) 
369 {
370         krb5_error_code ret;
371         TALLOC_CTX *tmp_ctx;
372         char **config_files;
373         const char *config_file;
374         
375         initialize_krb5_error_table();
376         
377         tmp_ctx = talloc_new(parent_ctx);
378         *smb_krb5_context = talloc(tmp_ctx, struct smb_krb5_context);
379
380         if (!*smb_krb5_context || !tmp_ctx) {
381                 talloc_free(tmp_ctx);
382                 return ENOMEM;
383         }
384
385         ret = krb5_init_context(&(*smb_krb5_context)->krb5_context);
386         if (ret) {
387                 DEBUG(1,("krb5_init_context failed (%s)\n", 
388                          error_message(ret)));
389                 talloc_free(tmp_ctx);
390                 return ret;
391         }
392
393         talloc_set_destructor(*smb_krb5_context, smb_krb5_context_destroy_1);
394
395         config_file = config_path(tmp_ctx, "krb5.conf");
396         if (!config_file) {
397                 talloc_free(tmp_ctx);
398                 return ENOMEM;
399         }
400                 
401         /* Use our local krb5.conf file by default */
402         ret = krb5_prepend_config_files_default(config_file, &config_files);
403         if (ret) {
404                 DEBUG(1,("krb5_prepend_config_files_default failed (%s)\n", 
405                          smb_get_krb5_error_message((*smb_krb5_context)->krb5_context, ret, tmp_ctx)));
406                 talloc_free(tmp_ctx);
407                 return ret;
408         }
409
410         ret = krb5_set_config_files((*smb_krb5_context)->krb5_context, 
411                                     config_files);
412         krb5_free_config_files(config_files);
413         if (ret) {
414                 DEBUG(1,("krb5_set_config_files failed (%s)\n", 
415                          smb_get_krb5_error_message((*smb_krb5_context)->krb5_context, ret, tmp_ctx)));
416                 talloc_free(tmp_ctx);
417                 return ret;
418         }
419                                                 
420         if (lp_realm() && *lp_realm()) {
421                 char *upper_realm = strupper_talloc(tmp_ctx, lp_realm());
422                 if (!upper_realm) {
423                         DEBUG(1,("gensec_krb5_start: could not uppercase realm: %s\n", lp_realm()));
424                         talloc_free(tmp_ctx);
425                         return ENOMEM;
426                 }
427                 ret = krb5_set_default_realm((*smb_krb5_context)->krb5_context, upper_realm);
428                 if (ret) {
429                         DEBUG(1,("krb5_set_default_realm failed (%s)\n", 
430                                  smb_get_krb5_error_message((*smb_krb5_context)->krb5_context, ret, tmp_ctx)));
431                         talloc_free(tmp_ctx);
432                         return ret;
433                 }
434         }
435
436         /* TODO: Should we have a different name here? */
437         ret = krb5_initlog((*smb_krb5_context)->krb5_context, "Samba", &(*smb_krb5_context)->logf);
438         
439         if (ret) {
440                 DEBUG(1,("krb5_initlog failed (%s)\n", 
441                          smb_get_krb5_error_message((*smb_krb5_context)->krb5_context, ret, tmp_ctx)));
442                 talloc_free(tmp_ctx);
443                 return ret;
444         }
445
446         talloc_set_destructor(*smb_krb5_context, smb_krb5_context_destroy_2);
447
448         ret = krb5_addlog_func((*smb_krb5_context)->krb5_context, (*smb_krb5_context)->logf, 0 /* min */, -1 /* max */, 
449                                smb_krb5_debug_wrapper, smb_krb5_debug_close, NULL);
450         if (ret) {
451                 DEBUG(1,("krb5_addlog_func failed (%s)\n", 
452                          smb_get_krb5_error_message((*smb_krb5_context)->krb5_context, ret, tmp_ctx)));
453                 talloc_free(tmp_ctx);
454                 return ret;
455         }
456         krb5_set_warn_dest((*smb_krb5_context)->krb5_context, (*smb_krb5_context)->logf);
457
458         /* Set use of our socket lib */
459         ret = krb5_set_send_to_kdc_func((*smb_krb5_context)->krb5_context, 
460                                         smb_krb5_send_and_recv_func, 
461                                         ev);
462         if (ret) {
463                 DEBUG(1,("krb5_set_send_recv_func failed (%s)\n", 
464                          smb_get_krb5_error_message((*smb_krb5_context)->krb5_context, ret, tmp_ctx)));
465                 talloc_free(tmp_ctx);
466                 return ret;
467         }
468
469         talloc_steal(parent_ctx, *smb_krb5_context);
470         talloc_free(tmp_ctx);
471
472         /* Set options in kerberos */
473
474         krb5_set_dns_canonicalize_hostname((*smb_krb5_context)->krb5_context,
475                                            lp_parm_bool(-1, "krb5", "set_dns_canonicalize", false));
476
477         return 0;
478 }
479