source3/libsmb/pylibsmb.c

   1 /*
   2  * Unix SMB/CIFS implementation.
   3  * Samba-internal work in progress Python binding for libsmbclient
   4  *
   5  * Copyright (C) Volker Lendecke 2012
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 3 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include <Python.h>
  22 #include "includes.h"
  23 #include "libsmb/libsmb.h"
  24 #include "libcli/security/security.h"
  25 #include "system/select.h"
  26 #include "source4/libcli/util/pyerrors.h"
  27 #include "auth/credentials/pycredentials.h"
  28
  29 static PyTypeObject *get_pytype(const char *module, const char *type)
  30 {
  31         PyObject *mod;
  32         PyTypeObject *result;
  33
  34         mod = PyImport_ImportModule(module);
  35         if (mod == NULL) {
  36                 PyErr_Format(PyExc_RuntimeError,
  37                              "Unable to import %s to check type %s",
  38                              module, type);
  39                 return NULL;
  40         }
  41         result = (PyTypeObject *)PyObject_GetAttrString(mod, type);
  42         Py_DECREF(mod);
  43         if (result == NULL) {
  44                 PyErr_Format(PyExc_RuntimeError,
  45                              "Unable to find type %s in module %s",
  46                              module, type);
  47                 return NULL;
  48         }
  49         return result;
  50 }
  51
  52 struct py_cli_thread;
  53
  54 struct py_cli_state {
  55         PyObject_HEAD
  56         struct cli_state *cli;
  57         struct tevent_context *ev;
  58         struct py_cli_thread *thread_state;
  59 };
  60
  61 #if HAVE_PTHREAD
  62
  63 #include <pthread.h>
  64
  65 struct py_cli_thread {
  66
  67         /*
  68          * Pipe to make the poll thread wake up in our destructor, so
  69          * that we can exit and join the thread.
  70          */
  71         int shutdown_pipe[2];
  72         struct tevent_fd *shutdown_fde;
  73         bool do_shutdown;
  74         pthread_t id;
  75
  76         /*
  77          * Thread state to release the GIL during the poll(2) syscall
  78          */
  79         PyThreadState *py_threadstate;
  80 };
  81
  82 static void *py_cli_state_poll_thread(void *private_data)
  83 {
  84         struct py_cli_state *self = (struct py_cli_state *)private_data;
  85         struct py_cli_thread *t = self->thread_state;
  86         PyGILState_STATE gstate;
  87
  88         gstate = PyGILState_Ensure();
  89
  90         while (!t->do_shutdown) {
  91                 int ret;
  92                 ret = tevent_loop_once(self->ev);
  93                 assert(ret == 0);
  94         }
  95         PyGILState_Release(gstate);
  96         return NULL;
  97 }
  98
  99 static void py_cli_state_trace_callback(enum tevent_trace_point point,
 100                                         void *private_data)
 101 {
 102         struct py_cli_state *self = (struct py_cli_state *)private_data;
 103         struct py_cli_thread *t = self->thread_state;
 104
 105         switch(point) {
 106         case TEVENT_TRACE_BEFORE_WAIT:
 107                 assert(t->py_threadstate == NULL);
 108                 t->py_threadstate = PyEval_SaveThread();
 109                 break;
 110         case TEVENT_TRACE_AFTER_WAIT:
 111                 assert(t->py_threadstate != NULL);
 112                 PyEval_RestoreThread(t->py_threadstate);
 113                 t->py_threadstate = NULL;
 114                 break;
 115         default:
 116                 break;
 117         }
 118 }
 119
 120 static void py_cli_state_shutdown_handler(struct tevent_context *ev,
 121                                           struct tevent_fd *fde,
 122                                           uint16_t flags,
 123                                           void *private_data)
 124 {
 125         struct py_cli_state *self = (struct py_cli_state *)private_data;
 126         struct py_cli_thread *t = self->thread_state;
 127
 128         if ((flags & TEVENT_FD_READ) == 0) {
 129                 return;
 130         }
 131         TALLOC_FREE(t->shutdown_fde);
 132         t->do_shutdown = true;
 133 }
 134
 135 static int py_cli_thread_destructor(struct py_cli_thread *t)
 136 {
 137         char c = 0;
 138         ssize_t written;
 139         int ret;
 140
 141         do {
 142                 /*
 143                  * This will wake the poll thread from the poll(2)
 144                  */
 145                 written = write(t->shutdown_pipe[1], &c, 1);
 146         } while ((written == -1) && (errno == EINTR));
 147
 148         /*
 149          * Allow the poll thread to do its own cleanup under the GIL
 150          */
 151         Py_BEGIN_ALLOW_THREADS
 152         ret = pthread_join(t->id, NULL);
 153         Py_END_ALLOW_THREADS
 154         assert(ret == 0);
 155
 156         if (t->shutdown_pipe[0] != -1) {
 157                 close(t->shutdown_pipe[0]);
 158                 t->shutdown_pipe[0] = -1;
 159         }
 160         if (t->shutdown_pipe[1] != -1) {
 161                 close(t->shutdown_pipe[1]);
 162                 t->shutdown_pipe[1] = -1;
 163         }
 164         return 0;
 165 }
 166
 167 static bool py_cli_state_setup_ev(struct py_cli_state *self)
 168 {
 169         struct py_cli_thread *t = NULL;
 170         int ret;
 171
 172         self->ev = tevent_context_init_byname(NULL, "poll_mt");
 173         if (self->ev == NULL) {
 174                 goto fail;
 175         }
 176         tevent_set_trace_callback(self->ev, py_cli_state_trace_callback, self);
 177
 178         self->thread_state = talloc_zero(NULL, struct py_cli_thread);
 179         if (self->thread_state == NULL) {
 180                 goto fail;
 181         }
 182         t = self->thread_state;
 183
 184         ret = pipe(t->shutdown_pipe);
 185         if (ret == -1) {
 186                 goto fail;
 187         }
 188         t->shutdown_fde = tevent_add_fd(
 189                 self->ev, self->ev, t->shutdown_pipe[0], TEVENT_FD_READ,
 190                 py_cli_state_shutdown_handler, self);
 191         if (t->shutdown_fde == NULL) {
 192                 goto fail;
 193         }
 194
 195         PyEval_InitThreads();
 196
 197         ret = pthread_create(&t->id, NULL, py_cli_state_poll_thread, self);
 198         if (ret != 0) {
 199                 goto fail;
 200         }
 201         talloc_set_destructor(self->thread_state, py_cli_thread_destructor);
 202         return true;
 203
 204 fail:
 205         if (t != NULL) {
 206                 TALLOC_FREE(t->shutdown_fde);
 207
 208                 if (t->shutdown_pipe[0] != -1) {
 209                         close(t->shutdown_pipe[0]);
 210                         t->shutdown_pipe[0] = -1;
 211                 }
 212                 if (t->shutdown_pipe[1] != -1) {
 213                         close(t->shutdown_pipe[1]);
 214                         t->shutdown_pipe[1] = -1;
 215                 }
 216                 TALLOC_FREE(t);
 217         }
 218
 219         TALLOC_FREE(self->thread_state);
 220         TALLOC_FREE(self->ev);
 221         return false;
 222 }
 223
 224 struct py_tevent_cond {
 225         pthread_mutex_t mutex;
 226         pthread_cond_t cond;
 227         bool is_done;
 228 };
 229
 230 static void py_tevent_signalme(struct tevent_req *req);
 231
 232 static int py_tevent_req_wait(struct tevent_context *ev,
 233                               struct tevent_req *req)
 234 {
 235         struct py_tevent_cond cond;
 236         int ret, result;
 237
 238         result = pthread_mutex_init(&cond.mutex, NULL);
 239         if (result != 0) {
 240                 goto fail;
 241         }
 242         result = pthread_cond_init(&cond.cond, NULL);
 243         if (result != 0) {
 244                 goto fail_mutex;
 245         }
 246
 247         cond.is_done = false;
 248         tevent_req_set_callback(req, py_tevent_signalme, &cond);
 249
 250         result = pthread_mutex_lock(&cond.mutex);
 251         if (result != 0) {
 252                 goto fail_cond;
 253         }
 254
 255         while (!cond.is_done) {
 256
 257                 Py_BEGIN_ALLOW_THREADS
 258                 result = pthread_cond_wait(&cond.cond, &cond.mutex);
 259                 Py_END_ALLOW_THREADS
 260
 261                 if (result != 0) {
 262                         goto fail_unlock;
 263                 }
 264         }
 265
 266 fail_unlock:
 267         ret = pthread_mutex_unlock(&cond.mutex);
 268         assert(ret == 0);
 269 fail_cond:
 270         ret = pthread_cond_destroy(&cond.cond);
 271         assert(ret == 0);
 272 fail_mutex:
 273         ret = pthread_mutex_destroy(&cond.mutex);
 274         assert(ret == 0);
 275 fail:
 276         return result;
 277 }
 278
 279 static void py_tevent_signalme(struct tevent_req *req)
 280 {
 281         struct py_tevent_cond *cond = (struct py_tevent_cond *)
 282                 tevent_req_callback_data_void(req);
 283         int ret;
 284
 285         ret = pthread_mutex_lock(&cond->mutex);
 286         assert(ret == 0);
 287
 288         cond->is_done = true;
 289
 290         ret = pthread_cond_signal(&cond->cond);
 291         assert(ret == 0);
 292         ret = pthread_mutex_unlock(&cond->mutex);
 293         assert(ret == 0);
 294 }
 295
 296 #else
 297
 298 static bool py_cli_state_setup_ev(struct py_cli_state *self)
 299 {
 300         self->ev = tevent_context_init(NULL);
 301         return (self->ev != NULL);
 302 }
 303
 304 static int py_tevent_req_wait(struct tevent_context *ev,
 305                               struct tevent_req *req)
 306 {
 307         while (tevent_req_is_in_progress(req)) {
 308                 int ret;
 309
 310                 ret = tevent_loop_once(ev);
 311                 if (ret != 0) {
 312                         return ret;
 313                 }
 314         }
 315         return 0;
 316 }
 317
 318 #endif
 319
 320 static PyObject *py_cli_state_new(PyTypeObject *type, PyObject *args,
 321                                   PyObject *kwds)
 322 {
 323         struct py_cli_state *self;
 324
 325         self = (struct py_cli_state *)type->tp_alloc(type, 0);
 326         if (self == NULL) {
 327                 return NULL;
 328         }
 329         self->cli = NULL;
 330         self->ev = NULL;
 331         self->thread_state = NULL;
 332         return (PyObject *)self;
 333 }
 334
 335 static int py_cli_state_init(struct py_cli_state *self, PyObject *args,
 336                              PyObject *kwds)
 337 {
 338         NTSTATUS status;
 339         char *host, *share;
 340         PyObject *creds;
 341         struct cli_credentials *cli_creds;
 342         bool ret;
 343
 344         static const char *kwlist[] = {
 345                 "host", "share", "credentials", NULL
 346         };
 347
 348         PyTypeObject *py_type_Credentials = get_pytype(
 349                 "samba.credentials", "Credentials");
 350         if (py_type_Credentials == NULL) {
 351                 return -1;
 352         }
 353
 354         ret = PyArg_ParseTupleAndKeywords(
 355                 args, kwds, "ss|O!", (char **)kwlist,
 356                 &host, &share, py_type_Credentials, &creds);
 357
 358         Py_DECREF(py_type_Credentials);
 359
 360         if (!ret) {
 361                 return -1;
 362         }
 363
 364         if (!py_cli_state_setup_ev(self)) {
 365                 return -1;
 366         }
 367
 368         cli_creds = cli_credentials_from_py_object(creds);
 369         if (cli_creds == NULL) {
 370                 PyErr_SetString(PyExc_TypeError, "Expected credentials");
 371                 return -1;
 372         }
 373
 374         status = cli_full_connection(
 375                 &self->cli, "myname", host, NULL, 0, share, "?????",
 376                 cli_credentials_get_username(cli_creds),
 377                 cli_credentials_get_domain(cli_creds),
 378                 cli_credentials_get_password(cli_creds),
 379                 0, 0);
 380         if (!NT_STATUS_IS_OK(status)) {
 381                 PyErr_SetNTSTATUS(status);
 382                 return -1;
 383         }
 384         return 0;
 385 }
 386
 387 static void py_cli_state_dealloc(struct py_cli_state *self)
 388 {
 389         TALLOC_FREE(self->thread_state);
 390         TALLOC_FREE(self->ev);
 391
 392         if (self->cli != NULL) {
 393                 cli_shutdown(self->cli);
 394                 self->cli = NULL;
 395         }
 396         self->ob_type->tp_free((PyObject *)self);
 397 }
 398
 399 static bool py_tevent_req_wait_exc(struct tevent_context *ev,
 400                                    struct tevent_req *req)
 401 {
 402         int ret;
 403
 404         if (req == NULL) {
 405                 PyErr_NoMemory();
 406                 return false;
 407         }
 408         ret = py_tevent_req_wait(ev, req);
 409         if (ret != 0) {
 410                 TALLOC_FREE(req);
 411                 errno = ret;
 412                 PyErr_SetFromErrno(PyExc_RuntimeError);
 413                 return false;
 414         }
 415         return true;
 416 }
 417
 418 static PyObject *py_cli_create(struct py_cli_state *self, PyObject *args,
 419                                PyObject *kwds)
 420 {
 421         char *fname;
 422         unsigned CreateFlags = 0;
 423         unsigned DesiredAccess = FILE_GENERIC_READ;
 424         unsigned FileAttributes = 0;
 425         unsigned ShareAccess = 0;
 426         unsigned CreateDisposition = FILE_OPEN;
 427         unsigned CreateOptions = 0;
 428         unsigned SecurityFlags = 0;
 429         uint16_t fnum;
 430         struct tevent_req *req;
 431         NTSTATUS status;
 432
 433         static const char *kwlist[] = {
 434                 "Name", "CreateFlags", "DesiredAccess", "FileAttributes",
 435                 "ShareAccess", "CreateDisposition", "CreateOptions",
 436                 "SecurityFlags", NULL };
 437
 438         if (!PyArg_ParseTupleAndKeywords(
 439                     args, kwds, "s|IIIIIII", (char **)kwlist,
 440                     &fname, &CreateFlags, &DesiredAccess, &FileAttributes,
 441                     &ShareAccess, &CreateDisposition, &CreateOptions,
 442                     &SecurityFlags)) {
 443                 return NULL;
 444         }
 445
 446         req = cli_ntcreate_send(NULL, self->ev, self->cli, fname, CreateFlags,
 447                                 DesiredAccess, FileAttributes, ShareAccess,
 448                                 CreateDisposition, CreateOptions,
 449                                 SecurityFlags);
 450         if (!py_tevent_req_wait_exc(self->ev, req)) {
 451                 return NULL;
 452         }
 453         status = cli_ntcreate_recv(req, &fnum);
 454         TALLOC_FREE(req);
 455
 456         if (!NT_STATUS_IS_OK(status)) {
 457                 PyErr_SetNTSTATUS(status);
 458                 return NULL;
 459         }
 460         return Py_BuildValue("I", (unsigned)fnum);
 461 }
 462
 463 static PyObject *py_cli_close(struct py_cli_state *self, PyObject *args)
 464 {
 465         struct tevent_req *req;
 466         int fnum;
 467         NTSTATUS status;
 468
 469         if (!PyArg_ParseTuple(args, "i", &fnum)) {
 470                 return NULL;
 471         }
 472
 473         req = cli_close_send(NULL, self->ev, self->cli, fnum);
 474         if (!py_tevent_req_wait_exc(self->ev, req)) {
 475                 return NULL;
 476         }
 477         status = cli_close_recv(req);
 478         TALLOC_FREE(req);
 479
 480         if (!NT_STATUS_IS_OK(status)) {
 481                 PyErr_SetNTSTATUS(status);
 482                 return NULL;
 483         }
 484         Py_INCREF(Py_None);
 485         return Py_None;
 486 }
 487
 488 static PyObject *py_cli_write(struct py_cli_state *self, PyObject *args,
 489                               PyObject *kwds)
 490 {
 491         int fnum;
 492         unsigned mode = 0;
 493         char *buf;
 494         int buflen;
 495         unsigned long long offset;
 496         struct tevent_req *req;
 497         NTSTATUS status;
 498         size_t written;
 499
 500         static const char *kwlist[] = {
 501                 "fnum", "buffer", "offset", "mode", NULL };
 502
 503         if (!PyArg_ParseTupleAndKeywords(
 504                     args, kwds, "Is#K|I", (char **)kwlist,
 505                     &fnum, &buf, &buflen, &offset, &mode)) {
 506                 return NULL;
 507         }
 508
 509         req = cli_write_andx_send(NULL, self->ev, self->cli, fnum, mode,
 510                                   (uint8_t *)buf, offset, buflen);
 511         if (!py_tevent_req_wait_exc(self->ev, req)) {
 512                 return NULL;
 513         }
 514         status = cli_write_andx_recv(req, &written);
 515         TALLOC_FREE(req);
 516
 517         if (!NT_STATUS_IS_OK(status)) {
 518                 PyErr_SetNTSTATUS(status);
 519                 return NULL;
 520         }
 521         return Py_BuildValue("K", (unsigned long long)written);
 522 }
 523
 524 static PyObject *py_cli_read(struct py_cli_state *self, PyObject *args,
 525                              PyObject *kwds)
 526 {
 527         int fnum;
 528         unsigned long long offset;
 529         unsigned size;
 530         struct tevent_req *req;
 531         NTSTATUS status;
 532         uint8_t *buf;
 533         ssize_t buflen;
 534         PyObject *result;
 535
 536         static const char *kwlist[] = {
 537                 "fnum", "offset", "size", NULL };
 538
 539         if (!PyArg_ParseTupleAndKeywords(
 540                     args, kwds, "IKI", (char **)kwlist, &fnum, &offset,
 541                     &size)) {
 542                 return NULL;
 543         }
 544
 545         req = cli_read_andx_send(NULL, self->ev, self->cli, fnum,
 546                                  offset, size);
 547         if (!py_tevent_req_wait_exc(self->ev, req)) {
 548                 return NULL;
 549         }
 550         status = cli_read_andx_recv(req, &buflen, &buf);
 551
 552         if (!NT_STATUS_IS_OK(status)) {
 553                 TALLOC_FREE(req);
 554                 PyErr_SetNTSTATUS(status);
 555                 return NULL;
 556         }
 557         result = Py_BuildValue("s#", (char *)buf, (int)buflen);
 558         TALLOC_FREE(req);
 559         return result;
 560 }
 561
 562 static PyObject *py_cli_ftruncate(struct py_cli_state *self, PyObject *args,
 563                                   PyObject *kwds)
 564 {
 565         int fnum;
 566         unsigned long long size;
 567         struct tevent_req *req;
 568         NTSTATUS status;
 569
 570         static const char *kwlist[] = {
 571                 "fnum", "size", NULL };
 572
 573         if (!PyArg_ParseTupleAndKeywords(
 574                     args, kwds, "IK", (char **)kwlist, &fnum, &size)) {
 575                 return NULL;
 576         }
 577
 578         req = cli_ftruncate_send(NULL, self->ev, self->cli, fnum, size);
 579         if (!py_tevent_req_wait_exc(self->ev, req)) {
 580                 return NULL;
 581         }
 582         status = cli_ftruncate_recv(req);
 583         TALLOC_FREE(req);
 584
 585         if (!NT_STATUS_IS_OK(status)) {
 586                 PyErr_SetNTSTATUS(status);
 587                 return NULL;
 588         }
 589         Py_INCREF(Py_None);
 590         return Py_None;
 591 }
 592
 593 static PyObject *py_cli_delete_on_close(struct py_cli_state *self,
 594                                         PyObject *args,
 595                                         PyObject *kwds)
 596 {
 597         unsigned fnum, flag;
 598         struct tevent_req *req;
 599         NTSTATUS status;
 600
 601         static const char *kwlist[] = {
 602                 "fnum", "flag", NULL };
 603
 604         if (!PyArg_ParseTupleAndKeywords(
 605                     args, kwds, "II", (char **)kwlist, &fnum, &flag)) {
 606                 return NULL;
 607         }
 608
 609         req = cli_nt_delete_on_close_send(NULL, self->ev, self->cli, fnum,
 610                                           flag);
 611         if (!py_tevent_req_wait_exc(self->ev, req)) {
 612                 return NULL;
 613         }
 614         status = cli_nt_delete_on_close_recv(req);
 615         TALLOC_FREE(req);
 616
 617         if (!NT_STATUS_IS_OK(status)) {
 618                 PyErr_SetNTSTATUS(status);
 619                 return NULL;
 620         }
 621         Py_INCREF(Py_None);
 622         return Py_None;
 623 }
 624
 625 static PyMethodDef py_cli_state_methods[] = {
 626         { "create", (PyCFunction)py_cli_create, METH_VARARGS|METH_KEYWORDS,
 627           "Open a file" },
 628         { "close", (PyCFunction)py_cli_close, METH_VARARGS,
 629           "Close a file handle" },
 630         { "write", (PyCFunction)py_cli_write, METH_VARARGS|METH_KEYWORDS,
 631           "Write to a file handle" },
 632         { "read", (PyCFunction)py_cli_read, METH_VARARGS|METH_KEYWORDS,
 633           "Read from a file handle" },
 634         { "truncate", (PyCFunction)py_cli_ftruncate,
 635           METH_VARARGS|METH_KEYWORDS,
 636           "Truncate a file" },
 637         { "delete_on_close", (PyCFunction)py_cli_delete_on_close,
 638           METH_VARARGS|METH_KEYWORDS,
 639           "Set/Reset the delete on close flag" },
 640         { NULL, NULL, 0, NULL }
 641 };
 642
 643 static PyTypeObject py_cli_state_type = {
 644         PyObject_HEAD_INIT(NULL)
 645         .tp_name = "libsmb_samba_internal.Conn",
 646         .tp_basicsize = sizeof(struct py_cli_state),
 647         .tp_flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE,
 648         .tp_doc = "libsmb connection",
 649         .tp_new = py_cli_state_new,
 650         .tp_init = (initproc)py_cli_state_init,
 651         .tp_dealloc = (destructor)py_cli_state_dealloc,
 652         .tp_methods = py_cli_state_methods,
 653 };
 654
 655 static PyMethodDef py_libsmb_methods[] = {
 656         { NULL },
 657 };
 658
 659 void initlibsmb_samba_internal(void);
 660 void initlibsmb_samba_internal(void)
 661 {
 662         PyObject *m;
 663
 664         talloc_stackframe();
 665
 666         m = Py_InitModule3("libsmb_samba_internal", py_libsmb_methods,
 667                            "libsmb wrapper");
 668
 669         if (PyType_Ready(&py_cli_state_type) < 0) {
 670                 return;
 671         }
 672         Py_INCREF(&py_cli_state_type);
 673         PyModule_AddObject(m, "Conn", (PyObject *)&py_cli_state_type);
 674 }