a5a30d94a1c99d4d70e7d234f6d5af24f963b1e0
[metze/samba/wip.git] / source3 / libsmb / libsmb_server.c
1 /*
2    Unix SMB/Netbios implementation.
3    SMB client library implementation
4    Copyright (C) Andrew Tridgell 1998
5    Copyright (C) Richard Sharpe 2000, 2002
6    Copyright (C) John Terpstra 2000
7    Copyright (C) Tom Jansen (Ninja ISD) 2002
8    Copyright (C) Derrell Lipman 2003-2008
9    Copyright (C) Jeremy Allison 2007, 2008
10    Copyright (C) SATOH Fumiyasu <fumiyas@osstech.co.jp> 2009.
11
12    This program is free software; you can redistribute it and/or modify
13    it under the terms of the GNU General Public License as published by
14    the Free Software Foundation; either version 3 of the License, or
15    (at your option) any later version.
16
17    This program is distributed in the hope that it will be useful,
18    but WITHOUT ANY WARRANTY; without even the implied warranty of
19    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20    GNU General Public License for more details.
21
22    You should have received a copy of the GNU General Public License
23    along with this program.  If not, see <http://www.gnu.org/licenses/>.
24 */
25
26 #include "includes.h"
27 #include "libsmb/libsmb.h"
28 #include "libsmbclient.h"
29 #include "libsmb_internal.h"
30 #include "../librpc/gen_ndr/ndr_lsa.h"
31 #include "rpc_client/cli_pipe.h"
32 #include "rpc_client/cli_lsarpc.h"
33 #include "libcli/security/security.h"
34 #include "libsmb/nmblib.h"
35 #include "../libcli/smb/smbXcli_base.h"
36
37 /*
38  * Check a server for being alive and well.
39  * returns 0 if the server is in shape. Returns 1 on error
40  *
41  * Also useable outside libsmbclient to enable external cache
42  * to do some checks too.
43  */
44 int
45 SMBC_check_server(SMBCCTX * context,
46                   SMBCSRV * server)
47 {
48         time_t now;
49
50         if (!cli_state_is_connected(server->cli)) {
51                 return 1;
52         }
53
54         now = time_mono(NULL);
55
56         if (server->last_echo_time == (time_t)0 ||
57                         now > server->last_echo_time +
58                                 (server->cli->timeout/1000)) {
59                 unsigned char data[16] = {0};
60                 NTSTATUS status = cli_echo(server->cli,
61                                         1,
62                                         data_blob_const(data, sizeof(data)));
63                 if (!NT_STATUS_IS_OK(status)) {
64                         /*
65                          * Some NetApp servers return
66                          * NT_STATUS_INVALID_PARAMETER.That's OK, they still
67                          * replied.
68                          * BUG: https://bugzilla.samba.org/show_bug.cgi?id=13007
69                          */
70                         if (!NT_STATUS_EQUAL(status,
71                                         NT_STATUS_INVALID_PARAMETER)) {
72                                 return 1;
73                         }
74                 }
75                 server->last_echo_time = now;
76         }
77         return 0;
78 }
79
80 /*
81  * Remove a server from the cached server list it's unused.
82  * On success, 0 is returned. 1 is returned if the server could not be removed.
83  *
84  * Also useable outside libsmbclient
85  */
86 int
87 SMBC_remove_unused_server(SMBCCTX * context,
88                           SMBCSRV * srv)
89 {
90         SMBCFILE * file;
91
92         /* are we being fooled ? */
93         if (!context || !context->internal->initialized || !srv) {
94                 return 1;
95         }
96
97         /* Check all open files/directories for a relation with this server */
98         for (file = context->internal->files; file; file = file->next) {
99                 if (file->srv == srv) {
100                         /* Still used */
101                         DEBUG(3, ("smbc_remove_usused_server: "
102                                   "%p still used by %p.\n",
103                                   srv, file));
104                         return 1;
105                 }
106         }
107
108         DLIST_REMOVE(context->internal->servers, srv);
109
110         cli_shutdown(srv->cli);
111         srv->cli = NULL;
112
113         DEBUG(3, ("smbc_remove_usused_server: %p removed.\n", srv));
114
115         smbc_getFunctionRemoveCachedServer(context)(context, srv);
116
117         SAFE_FREE(srv);
118         return 0;
119 }
120
121 /****************************************************************
122  * Call the auth_fn with fixed size (fstring) buffers.
123  ***************************************************************/
124 static void
125 SMBC_call_auth_fn(TALLOC_CTX *ctx,
126                   SMBCCTX *context,
127                   const char *server,
128                   const char *share,
129                   char **pp_workgroup,
130                   char **pp_username,
131                   char **pp_password)
132 {
133         fstring workgroup = { 0 };
134         fstring username = { 0 };
135         fstring password = { 0 };
136         smbc_get_auth_data_with_context_fn auth_with_context_fn;
137
138         if (*pp_workgroup != NULL) {
139                 strlcpy(workgroup, *pp_workgroup, sizeof(workgroup));
140         }
141         if (*pp_username != NULL) {
142                 strlcpy(username, *pp_username, sizeof(username));
143         }
144         if (*pp_password != NULL) {
145                 strlcpy(password, *pp_password, sizeof(password));
146         }
147
148         /* See if there's an authentication with context function provided */
149         auth_with_context_fn = smbc_getFunctionAuthDataWithContext(context);
150         if (auth_with_context_fn)
151         {
152             (* auth_with_context_fn)(context,
153                                      server, share,
154                                      workgroup, sizeof(workgroup),
155                                      username, sizeof(username),
156                                      password, sizeof(password));
157         }
158         else
159         {
160             smbc_getFunctionAuthData(context)(server, share,
161                                               workgroup, sizeof(workgroup),
162                                               username, sizeof(username),
163                                               password, sizeof(password));
164         }
165
166         TALLOC_FREE(*pp_workgroup);
167         TALLOC_FREE(*pp_username);
168         TALLOC_FREE(*pp_password);
169
170         *pp_workgroup = talloc_strdup(ctx, workgroup);
171         *pp_username = talloc_strdup(ctx, username);
172         *pp_password = talloc_strdup(ctx, password);
173 }
174
175
176 void
177 SMBC_get_auth_data(const char *server, const char *share,
178                    char *workgroup_buf, int workgroup_buf_len,
179                    char *username_buf, int username_buf_len,
180                    char *password_buf, int password_buf_len)
181 {
182         /* Default function just uses provided data.  Nothing to do. */
183 }
184
185
186
187 SMBCSRV *
188 SMBC_find_server(TALLOC_CTX *ctx,
189                  SMBCCTX *context,
190                  const char *server,
191                  const char *share,
192                  char **pp_workgroup,
193                  char **pp_username,
194                  char **pp_password)
195 {
196         SMBCSRV *srv;
197         int auth_called = 0;
198
199         if (!pp_workgroup || !pp_username || !pp_password) {
200                 return NULL;
201         }
202
203 check_server_cache:
204
205         srv = smbc_getFunctionGetCachedServer(context)(context,
206                                                        server, share,
207                                                        *pp_workgroup,
208                                                        *pp_username);
209
210         if (!auth_called && !srv && (!*pp_username || !(*pp_username)[0] ||
211                                      !*pp_password || !(*pp_password)[0])) {
212                 SMBC_call_auth_fn(ctx, context, server, share,
213                                   pp_workgroup, pp_username, pp_password);
214
215                 /*
216                  * However, smbc_auth_fn may have picked up info relating to
217                  * an existing connection, so try for an existing connection
218                  * again ...
219                  */
220                 auth_called = 1;
221                 goto check_server_cache;
222
223         }
224
225         if (srv) {
226                 if (smbc_getFunctionCheckServer(context)(context, srv)) {
227                         /*
228                          * This server is no good anymore
229                          * Try to remove it and check for more possible
230                          * servers in the cache
231                          */
232                         if (smbc_getFunctionRemoveUnusedServer(context)(context,
233                                                                         srv)) {
234                                 /*
235                                  * We could not remove the server completely,
236                                  * remove it from the cache so we will not get
237                                  * it again. It will be removed when the last
238                                  * file/dir is closed.
239                                  */
240                                 smbc_getFunctionRemoveCachedServer(context)(context,
241                                                                             srv);
242                         }
243
244                         /*
245                          * Maybe there are more cached connections to this
246                          * server
247                          */
248                         goto check_server_cache;
249                 }
250
251                 return srv;
252         }
253
254         return NULL;
255 }
256
257 /*
258  * Connect to a server, possibly on an existing connection
259  *
260  * Here, what we want to do is: If the server and username
261  * match an existing connection, reuse that, otherwise, establish a
262  * new connection.
263  *
264  * If we have to create a new connection, call the auth_fn to get the
265  * info we need, unless the username and password were passed in.
266  */
267
268 static SMBCSRV *
269 SMBC_server_internal(TALLOC_CTX *ctx,
270             SMBCCTX *context,
271             bool connect_if_not_found,
272             const char *server,
273             uint16_t port,
274             const char *share,
275             char **pp_workgroup,
276             char **pp_username,
277             char **pp_password,
278             bool *in_cache)
279 {
280         SMBCSRV *srv=NULL;
281         char *workgroup = NULL;
282         struct cli_state *c = NULL;
283         const char *server_n = server;
284         int is_ipc = (share != NULL && strcmp(share, "IPC$") == 0);
285         uint32_t fs_attrs = 0;
286         const char *username_used = NULL;
287         const char *password_used = NULL;
288         NTSTATUS status;
289         char *newserver, *newshare;
290         int flags = 0;
291         struct smbXcli_tcon *tcon = NULL;
292         int signing_state = SMB_SIGNING_DEFAULT;
293         struct cli_credentials *creds = NULL;
294         bool use_kerberos = false;
295         bool fallback_after_kerberos = false;
296         bool use_ccache = false;
297         bool pw_nt_hash = false;
298
299         ZERO_STRUCT(c);
300         *in_cache = false;
301
302         if (server[0] == 0) {
303                 errno = EPERM;
304                 return NULL;
305         }
306
307         /* Look for a cached connection */
308         srv = SMBC_find_server(ctx, context, server, share,
309                                pp_workgroup, pp_username, pp_password);
310
311         /*
312          * If we found a connection and we're only allowed one share per
313          * server...
314          */
315         if (srv &&
316             share != NULL && *share != '\0' &&
317             smbc_getOptionOneSharePerServer(context)) {
318
319                 /*
320                  * ... then if there's no current connection to the share,
321                  * connect to it.  SMBC_find_server(), or rather the function
322                  * pointed to by context->get_cached_srv_fn which
323                  * was called by SMBC_find_server(), will have issued a tree
324                  * disconnect if the requested share is not the same as the
325                  * one that was already connected.
326                  */
327
328                 /*
329                  * Use srv->cli->desthost and srv->cli->share instead of
330                  * server and share below to connect to the actual share,
331                  * i.e., a normal share or a referred share from
332                  * 'msdfs proxy' share.
333                  */
334                 if (!cli_state_has_tcon(srv->cli)) {
335                         /* Ensure we have accurate auth info */
336                         SMBC_call_auth_fn(ctx, context,
337                                           smbXcli_conn_remote_name(srv->cli->conn),
338                                           srv->cli->share,
339                                           pp_workgroup,
340                                           pp_username,
341                                           pp_password);
342
343                         if (!*pp_workgroup || !*pp_username || !*pp_password) {
344                                 errno = ENOMEM;
345                                 cli_shutdown(srv->cli);
346                                 srv->cli = NULL;
347                                 smbc_getFunctionRemoveCachedServer(context)(context,
348                                                                             srv);
349                                 return NULL;
350                         }
351
352                         /*
353                          * We don't need to renegotiate encryption
354                          * here as the encryption context is not per
355                          * tid.
356                          */
357
358                         status = cli_tree_connect(srv->cli,
359                                                   srv->cli->share,
360                                                   "?????",
361                                                   *pp_password);
362                         if (!NT_STATUS_IS_OK(status)) {
363                                 cli_shutdown(srv->cli);
364                                 errno = map_errno_from_nt_status(status);
365                                 srv->cli = NULL;
366                                 smbc_getFunctionRemoveCachedServer(context)(context,
367                                                                             srv);
368                                 srv = NULL;
369                         }
370
371                         /* Determine if this share supports case sensitivity */
372                         if (is_ipc) {
373                                 DEBUG(4,
374                                       ("IPC$ so ignore case sensitivity\n"));
375                                 status = NT_STATUS_OK;
376                         } else {
377                                 status = cli_get_fs_attr_info(c, &fs_attrs);
378                         }
379
380                         if (!NT_STATUS_IS_OK(status)) {
381                                 DEBUG(4, ("Could not retrieve "
382                                           "case sensitivity flag: %s.\n",
383                                           nt_errstr(status)));
384
385                                 /*
386                                  * We can't determine the case sensitivity of
387                                  * the share. We have no choice but to use the
388                                  * user-specified case sensitivity setting.
389                                  */
390                                 if (smbc_getOptionCaseSensitive(context)) {
391                                         cli_set_case_sensitive(c, True);
392                                 } else {
393                                         cli_set_case_sensitive(c, False);
394                                 }
395                         } else if (!is_ipc) {
396                                 DEBUG(4,
397                                       ("Case sensitive: %s\n",
398                                        (fs_attrs & FILE_CASE_SENSITIVE_SEARCH
399                                         ? "True"
400                                         : "False")));
401                                 cli_set_case_sensitive(
402                                         c,
403                                         (fs_attrs & FILE_CASE_SENSITIVE_SEARCH
404                                          ? True
405                                          : False));
406                         }
407
408                         /*
409                          * Regenerate the dev value since it's based on both
410                          * server and share
411                          */
412                         if (srv) {
413                                 const char *remote_name =
414                                         smbXcli_conn_remote_name(srv->cli->conn);
415
416                                 srv->dev = (dev_t)(str_checksum(remote_name) ^
417                                                    str_checksum(srv->cli->share));
418                         }
419                 }
420         }
421
422         /* If we have a connection... */
423         if (srv) {
424
425                 /* ... then we're done here.  Give 'em what they came for. */
426                 *in_cache = true;
427                 goto done;
428         }
429
430         /* If we're not asked to connect when a connection doesn't exist... */
431         if (! connect_if_not_found) {
432                 /* ... then we're done here. */
433                 return NULL;
434         }
435
436         if (!*pp_workgroup || !*pp_username || !*pp_password) {
437                 errno = ENOMEM;
438                 return NULL;
439         }
440
441         DEBUG(4,("SMBC_server: server_n=[%s] server=[%s]\n", server_n, server));
442
443         DEBUG(4,(" -> server_n=[%s] server=[%s]\n", server_n, server));
444
445         status = NT_STATUS_UNSUCCESSFUL;
446
447         if (smbc_getOptionUseKerberos(context)) {
448                 flags |= CLI_FULL_CONNECTION_USE_KERBEROS;
449                 use_kerberos = true;
450         }
451
452         if (smbc_getOptionFallbackAfterKerberos(context)) {
453                 flags |= CLI_FULL_CONNECTION_FALLBACK_AFTER_KERBEROS;
454                 fallback_after_kerberos = true;
455         }
456
457         if (smbc_getOptionUseCCache(context)) {
458                 flags |= CLI_FULL_CONNECTION_USE_CCACHE;
459                 use_ccache = true;
460         }
461
462         if (smbc_getOptionUseNTHash(context)) {
463                 flags |= CLI_FULL_CONNECTION_USE_NT_HASH;
464                 pw_nt_hash = true;
465         }
466
467         if (context->internal->smb_encryption_level != SMBC_ENCRYPTLEVEL_NONE) {
468                 signing_state = SMB_SIGNING_REQUIRED;
469         }
470
471         if (port == 0) {
472                 if (share == NULL || *share == '\0' || is_ipc) {
473                         /*
474                          * Try 139 first for IPC$
475                          */
476                         status = cli_connect_nb(server_n, NULL, NBT_SMB_PORT, 0x20,
477                                         smbc_getNetbiosName(context),
478                                         signing_state, flags, &c);
479                 }
480         }
481
482         if (!NT_STATUS_IS_OK(status)) {
483                 /*
484                  * No IPC$ or 139 did not work
485                  */
486                 status = cli_connect_nb(server_n, NULL, port, 0x20,
487                                         smbc_getNetbiosName(context),
488                                         signing_state, flags, &c);
489         }
490
491         if (!NT_STATUS_IS_OK(status)) {
492                 if (NT_STATUS_EQUAL(status, NT_STATUS_NOT_SUPPORTED)) {
493                         DBG_ERR("NetBIOS support disabled, unable to connect");
494                 }
495
496                 errno = map_errno_from_nt_status(status);
497                 return NULL;
498         }
499
500         cli_set_timeout(c, smbc_getTimeout(context));
501
502         status = smbXcli_negprot(c->conn, c->timeout,
503                                  lp_client_min_protocol(),
504                                  lp_client_max_protocol());
505         if (!NT_STATUS_IS_OK(status)) {
506                 cli_shutdown(c);
507                 errno = map_errno_from_nt_status(status);
508                 return NULL;
509         }
510
511         status = cli_state_update_after_negprot(c);
512         if (!NT_STATUS_IS_OK(status)) {
513                 cli_shutdown(c);
514                 errno = ENOMEM;
515                 return NULL;
516         }
517
518         username_used = *pp_username;
519         password_used = *pp_password;
520
521         creds = cli_session_creds_init(c,
522                                        username_used,
523                                        *pp_workgroup,
524                                        NULL, /* realm */
525                                        password_used,
526                                        use_kerberos,
527                                        fallback_after_kerberos,
528                                        use_ccache,
529                                        pw_nt_hash);
530         if (creds == NULL) {
531                 cli_shutdown(c);
532                 errno = ENOMEM;
533                 return NULL;
534         }
535
536         status = cli_session_setup_creds(c, creds);
537         if (!NT_STATUS_IS_OK(status)) {
538
539                 /* Failed.  Try an anonymous login, if allowed by flags. */
540                 username_used = "";
541                 password_used = "";
542
543                 if (smbc_getOptionNoAutoAnonymousLogin(context) ||
544                     !NT_STATUS_IS_OK(cli_session_setup_anon(c))) {
545
546                         cli_shutdown(c);
547                         errno = EPERM;
548                         return NULL;
549                 }
550         }
551
552         DEBUG(4,(" session setup ok\n"));
553
554         /* here's the fun part....to support 'msdfs proxy' shares
555            (on Samba or windows) we have to issues a TRANS_GET_DFS_REFERRAL
556            here before trying to connect to the original share.
557            cli_check_msdfs_proxy() will fail if it is a normal share. */
558
559         if (smbXcli_conn_dfs_supported(c->conn) &&
560                         cli_check_msdfs_proxy(ctx, c, share,
561                                 &newserver, &newshare,
562                                 /* FIXME: cli_check_msdfs_proxy() does
563                                    not support smbc_smb_encrypt_level type */
564                                 context->internal->smb_encryption_level ?
565                                         true : false,
566                                 creds)) {
567                 cli_shutdown(c);
568                 srv = SMBC_server_internal(ctx, context, connect_if_not_found,
569                                 newserver, port, newshare, pp_workgroup,
570                                 pp_username, pp_password, in_cache);
571                 TALLOC_FREE(newserver);
572                 TALLOC_FREE(newshare);
573                 return srv;
574         }
575
576         /* must be a normal share */
577
578         status = cli_tree_connect_creds(c, share, "?????", creds);
579         if (!NT_STATUS_IS_OK(status)) {
580                 cli_shutdown(c);
581                 errno = map_errno_from_nt_status(status);
582                 return NULL;
583         }
584
585         DEBUG(4,(" tconx ok\n"));
586
587         if (smbXcli_conn_protocol(c->conn) >= PROTOCOL_SMB2_02) {
588                 tcon = c->smb2.tcon;
589         } else {
590                 tcon = c->smb1.tcon;
591         }
592
593         /* Determine if this share supports case sensitivity */
594         if (is_ipc) {
595                 DEBUG(4, ("IPC$ so ignore case sensitivity\n"));
596                 status = NT_STATUS_OK;
597         } else {
598                 status = cli_get_fs_attr_info(c, &fs_attrs);
599         }
600
601         if (!NT_STATUS_IS_OK(status)) {
602                 DEBUG(4, ("Could not retrieve case sensitivity flag: %s.\n",
603                           nt_errstr(status)));
604
605                 /*
606                  * We can't determine the case sensitivity of the share. We
607                  * have no choice but to use the user-specified case
608                  * sensitivity setting.
609                  */
610                 if (smbc_getOptionCaseSensitive(context)) {
611                         cli_set_case_sensitive(c, True);
612                 } else {
613                         cli_set_case_sensitive(c, False);
614                 }
615         } else if (!is_ipc) {
616                 DEBUG(4, ("Case sensitive: %s\n",
617                           (fs_attrs & FILE_CASE_SENSITIVE_SEARCH
618                            ? "True"
619                            : "False")));
620                 smbXcli_tcon_set_fs_attributes(tcon, fs_attrs);
621         }
622
623         if (context->internal->smb_encryption_level) {
624                 /* Attempt encryption. */
625                 status = cli_cm_force_encryption_creds(c,
626                                                        creds,
627                                                        share);
628                 if (!NT_STATUS_IS_OK(status)) {
629
630                         /*
631                          * context->smb_encryption_level == 1
632                          * means don't fail if encryption can't be negotiated,
633                          * == 2 means fail if encryption can't be negotiated.
634                          */
635
636                         DEBUG(4,(" SMB encrypt failed\n"));
637
638                         if (context->internal->smb_encryption_level == 2) {
639                                 cli_shutdown(c);
640                                 errno = EPERM;
641                                 return NULL;
642                         }
643                 }
644                 DEBUG(4,(" SMB encrypt ok\n"));
645         }
646
647         /*
648          * Ok, we have got a nice connection
649          * Let's allocate a server structure.
650          */
651
652         srv = SMB_MALLOC_P(SMBCSRV);
653         if (!srv) {
654                 cli_shutdown(c);
655                 errno = ENOMEM;
656                 return NULL;
657         }
658
659         ZERO_STRUCTP(srv);
660         DLIST_ADD(srv->cli, c);
661         srv->dev = (dev_t)(str_checksum(server) ^ str_checksum(share));
662         srv->no_pathinfo = False;
663         srv->no_pathinfo2 = False;
664         srv->no_pathinfo3 = False;
665         srv->no_nt_session = False;
666
667 done:
668         if (!pp_workgroup || !*pp_workgroup || !**pp_workgroup) {
669                 workgroup = talloc_strdup(ctx, smbc_getWorkgroup(context));
670         } else {
671                 workgroup = *pp_workgroup;
672         }
673         if(!workgroup) {
674                 if (c != NULL) {
675                         cli_shutdown(c);
676                 }
677                 SAFE_FREE(srv);
678                 return NULL;
679         }
680
681         /* set the credentials to make DFS work */
682         smbc_set_credentials_with_fallback(context,
683                                            workgroup,
684                                            *pp_username,
685                                            *pp_password);
686
687         return srv;
688 }
689
690 SMBCSRV *
691 SMBC_server(TALLOC_CTX *ctx,
692                 SMBCCTX *context,
693                 bool connect_if_not_found,
694                 const char *server,
695                 uint16_t port,
696                 const char *share,
697                 char **pp_workgroup,
698                 char **pp_username,
699                 char **pp_password)
700 {
701         SMBCSRV *srv=NULL;
702         bool in_cache = false;
703
704         srv = SMBC_server_internal(ctx, context, connect_if_not_found,
705                         server, port, share, pp_workgroup,
706                         pp_username, pp_password, &in_cache);
707
708         if (!srv) {
709                 return NULL;
710         }
711         if (in_cache) {
712                 return srv;
713         }
714
715         /* Now add it to the cache (internal or external)  */
716         /* Let the cache function set errno if it wants to */
717         errno = 0;
718         if (smbc_getFunctionAddCachedServer(context)(context, srv,
719                                                 server, share,
720                                                 *pp_workgroup,
721                                                 *pp_username)) {
722                 int saved_errno = errno;
723                 DEBUG(3, (" Failed to add server to cache\n"));
724                 errno = saved_errno;
725                 if (errno == 0) {
726                         errno = ENOMEM;
727                 }
728                 SAFE_FREE(srv);
729                 return NULL;
730         }
731
732         DEBUG(2, ("Server connect ok: //%s/%s: %p\n",
733                 server, share, srv));
734
735         DLIST_ADD(context->internal->servers, srv);
736         return srv;
737 }
738
739 /*
740  * Connect to a server for getting/setting attributes, possibly on an existing
741  * connection.  This works similarly to SMBC_server().
742  */
743 SMBCSRV *
744 SMBC_attr_server(TALLOC_CTX *ctx,
745                  SMBCCTX *context,
746                  const char *server,
747                  uint16_t port,
748                  const char *share,
749                  char **pp_workgroup,
750                  char **pp_username,
751                  char **pp_password)
752 {
753         int flags;
754         struct cli_state *ipc_cli = NULL;
755         struct rpc_pipe_client *pipe_hnd = NULL;
756         NTSTATUS nt_status;
757         SMBCSRV *srv=NULL;
758         SMBCSRV *ipc_srv=NULL;
759
760         /*
761          * Use srv->cli->desthost and srv->cli->share instead of
762          * server and share below to connect to the actual share,
763          * i.e., a normal share or a referred share from
764          * 'msdfs proxy' share.
765          */
766         srv = SMBC_server(ctx, context, true, server, port, share,
767                         pp_workgroup, pp_username, pp_password);
768         if (!srv) {
769                 return NULL;
770         }
771         server = smbXcli_conn_remote_name(srv->cli->conn);
772         share = srv->cli->share;
773
774         /*
775          * See if we've already created this special connection.  Reference
776          * our "special" share name '*IPC$', which is an impossible real share
777          * name due to the leading asterisk.
778          */
779         ipc_srv = SMBC_find_server(ctx, context, server, "*IPC$",
780                                    pp_workgroup, pp_username, pp_password);
781         if (!ipc_srv) {
782                 int signing_state = SMB_SIGNING_DEFAULT;
783
784                 /* We didn't find a cached connection.  Get the password */
785                 if (!*pp_password || (*pp_password)[0] == '\0') {
786                         /* ... then retrieve it now. */
787                         SMBC_call_auth_fn(ctx, context, server, share,
788                                           pp_workgroup,
789                                           pp_username,
790                                           pp_password);
791                         if (!*pp_workgroup || !*pp_username || !*pp_password) {
792                                 errno = ENOMEM;
793                                 return NULL;
794                         }
795                 }
796
797                 flags = 0;
798                 if (smbc_getOptionUseKerberos(context)) {
799                         flags |= CLI_FULL_CONNECTION_USE_KERBEROS;
800                 }
801                 if (smbc_getOptionUseCCache(context)) {
802                         flags |= CLI_FULL_CONNECTION_USE_CCACHE;
803                 }
804                 if (context->internal->smb_encryption_level != SMBC_ENCRYPTLEVEL_NONE) {
805                         signing_state = SMB_SIGNING_REQUIRED;
806                 }
807
808                 nt_status = cli_full_connection(&ipc_cli,
809                                                 lp_netbios_name(), server,
810                                                 NULL, 0, "IPC$", "?????",
811                                                 *pp_username,
812                                                 *pp_workgroup,
813                                                 *pp_password,
814                                                 flags,
815                                                 signing_state);
816                 if (! NT_STATUS_IS_OK(nt_status)) {
817                         DEBUG(1,("cli_full_connection failed! (%s)\n",
818                                  nt_errstr(nt_status)));
819                         errno = ENOTSUP;
820                         return NULL;
821                 }
822
823                 if (context->internal->smb_encryption_level) {
824                         /* Attempt encryption. */
825                         nt_status = cli_cm_force_encryption(ipc_cli,
826                                                             *pp_username,
827                                                             *pp_password,
828                                                             *pp_workgroup,
829                                                             "IPC$");
830                         if (!NT_STATUS_IS_OK(nt_status)) {
831
832                                 /*
833                                  * context->smb_encryption_level ==
834                                  * 1 means don't fail if encryption can't be
835                                  * negotiated, == 2 means fail if encryption
836                                  * can't be negotiated.
837                                  */
838
839                                 DEBUG(4,(" SMB encrypt failed on IPC$\n"));
840
841                                 if (context->internal->smb_encryption_level == 2) {
842                                         cli_shutdown(ipc_cli);
843                                         errno = EPERM;
844                                         return NULL;
845                                 }
846                         }
847                         DEBUG(4,(" SMB encrypt ok on IPC$\n"));
848                 }
849
850                 ipc_srv = SMB_MALLOC_P(SMBCSRV);
851                 if (!ipc_srv) {
852                         errno = ENOMEM;
853                         cli_shutdown(ipc_cli);
854                         return NULL;
855                 }
856
857                 ZERO_STRUCTP(ipc_srv);
858                 DLIST_ADD(ipc_srv->cli, ipc_cli);
859
860                 nt_status = cli_rpc_pipe_open_noauth(
861                         ipc_srv->cli, &ndr_table_lsarpc, &pipe_hnd);
862                 if (!NT_STATUS_IS_OK(nt_status)) {
863                         DEBUG(1, ("cli_nt_session_open fail!\n"));
864                         errno = ENOTSUP;
865                         cli_shutdown(ipc_srv->cli);
866                         free(ipc_srv);
867                         return NULL;
868                 }
869
870                 /*
871                  * Some systems don't support
872                  * SEC_FLAG_MAXIMUM_ALLOWED, but NT sends 0x2000000
873                  * so we might as well do it too.
874                  */
875
876                 nt_status = rpccli_lsa_open_policy(
877                         pipe_hnd,
878                         talloc_tos(),
879                         True,
880                         GENERIC_EXECUTE_ACCESS,
881                         &ipc_srv->pol);
882
883                 if (!NT_STATUS_IS_OK(nt_status)) {
884                         errno = SMBC_errno(context, ipc_srv->cli);
885                         cli_shutdown(ipc_srv->cli);
886                         free(ipc_srv);
887                         return NULL;
888                 }
889
890                 /* now add it to the cache (internal or external) */
891
892                 errno = 0;      /* let cache function set errno if it likes */
893                 if (smbc_getFunctionAddCachedServer(context)(context, ipc_srv,
894                                                              server,
895                                                              "*IPC$",
896                                                              *pp_workgroup,
897                                                              *pp_username)) {
898                         DEBUG(3, (" Failed to add server to cache\n"));
899                         if (errno == 0) {
900                                 errno = ENOMEM;
901                         }
902                         cli_shutdown(ipc_srv->cli);
903                         free(ipc_srv);
904                         return NULL;
905                 }
906
907                 DLIST_ADD(context->internal->servers, ipc_srv);
908         }
909
910         return ipc_srv;
911 }