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;
 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         TALLOC_FREE(t->shutdown_fde);
 206
 207         if (t->shutdown_pipe[0] != -1) {
 208                 close(t->shutdown_pipe[0]);
 209                 t->shutdown_pipe[0] = -1;
 210         }
 211         if (t->shutdown_pipe[1] != -1) {
 212                 close(t->shutdown_pipe[1]);
 213                 t->shutdown_pipe[1] = -1;
 214         }
 215
 216         TALLOC_FREE(self->thread_state);
 217         TALLOC_FREE(self->ev);
 218         return false;
 219 }
 220
 221 struct py_tevent_cond {
 222         pthread_mutex_t mutex;
 223         pthread_cond_t cond;
 224         bool is_done;
 225 };
 226
 227 static void py_tevent_signalme(struct tevent_req *req);
 228
 229 static int py_tevent_req_wait(struct tevent_context *ev,
 230                               struct tevent_req *req)
 231 {
 232         struct py_tevent_cond cond;
 233         int ret, result;
 234
 235         result = pthread_mutex_init(&cond.mutex, NULL);
 236         if (result != 0) {
 237                 goto fail;
 238         }
 239         result = pthread_cond_init(&cond.cond, NULL);
 240         if (result != 0) {
 241                 goto fail_mutex;
 242         }
 243
 244         cond.is_done = false;
 245         tevent_req_set_callback(req, py_tevent_signalme, &cond);
 246
 247         result = pthread_mutex_lock(&cond.mutex);
 248         if (result != 0) {
 249                 goto fail_cond;
 250         }
 251
 252         while (!cond.is_done) {
 253
 254                 Py_BEGIN_ALLOW_THREADS
 255                 result = pthread_cond_wait(&cond.cond, &cond.mutex);
 256                 Py_END_ALLOW_THREADS
 257
 258                 if (result != 0) {
 259                         goto fail_unlock;
 260                 }
 261         }
 262
 263 fail_unlock:
 264         ret = pthread_mutex_unlock(&cond.mutex);
 265         assert(ret == 0);
 266 fail_cond:
 267         ret = pthread_cond_destroy(&cond.cond);
 268         assert(ret == 0);
 269 fail_mutex:
 270         ret = pthread_mutex_destroy(&cond.mutex);
 271         assert(ret == 0);
 272 fail:
 273         return result;
 274 }
 275
 276 static void py_tevent_signalme(struct tevent_req *req)
 277 {
 278         struct py_tevent_cond *cond = (struct py_tevent_cond *)
 279                 tevent_req_callback_data_void(req);
 280         int ret;
 281
 282         ret = pthread_mutex_lock(&cond->mutex);
 283         assert(ret == 0);
 284
 285         cond->is_done = true;
 286
 287         ret = pthread_cond_signal(&cond->cond);
 288         assert(ret == 0);
 289         ret = pthread_mutex_unlock(&cond->mutex);
 290         assert(ret == 0);
 291 }
 292
 293 #else
 294
 295 static bool py_cli_state_setup_ev(struct py_cli_state *self)
 296 {
 297         self->ev = tevent_context_init(NULL);
 298         return (self->ev != NULL);
 299 }
 300
 301 static int py_tevent_req_wait(struct tevent_context *ev,
 302                               struct tevent_req *req)
 303 {
 304         while (tevent_req_is_in_progress(req)) {
 305                 int ret;
 306
 307                 ret = tevent_loop_once(ev);
 308                 if (ret != 0) {
 309                         return ret;
 310                 }
 311         }
 312         return 0;
 313 }
 314
 315 #endif
 316
 317 static PyObject *py_cli_state_new(PyTypeObject *type, PyObject *args,
 318                                   PyObject *kwds)
 319 {
 320         struct py_cli_state *self;
 321
 322         self = (struct py_cli_state *)type->tp_alloc(type, 0);
 323         if (self == NULL) {
 324                 return NULL;
 325         }
 326         self->cli = NULL;
 327         self->ev = NULL;
 328         self->thread_state = NULL;
 329         return (PyObject *)self;
 330 }
 331
 332 static int py_cli_state_init(struct py_cli_state *self, PyObject *args,
 333                              PyObject *kwds)
 334 {
 335         NTSTATUS status;
 336         char *host, *share;
 337         PyObject *creds;
 338         struct cli_credentials *cli_creds;
 339         bool ret;
 340
 341         static const char *kwlist[] = {
 342                 "host", "share", "credentials", NULL
 343         };
 344
 345         PyTypeObject *py_type_Credentials = get_pytype(
 346                 "samba.credentials", "Credentials");
 347         if (py_type_Credentials == NULL) {
 348                 return -1;
 349         }
 350
 351         ret = PyArg_ParseTupleAndKeywords(
 352                 args, kwds, "ss|O!", (char **)kwlist,
 353                 &host, &share, py_type_Credentials, &creds);
 354
 355         Py_DECREF(py_type_Credentials);
 356
 357         if (!ret) {
 358                 return -1;
 359         }
 360
 361         if (!py_cli_state_setup_ev(self)) {
 362                 return -1;
 363         }
 364
 365         cli_creds = cli_credentials_from_py_object(creds);
 366         if (cli_creds == NULL) {
 367                 PyErr_SetString(PyExc_TypeError, "Expected credentials");
 368                 return -1;
 369         }
 370
 371         status = cli_full_connection(
 372                 &self->cli, "myname", host, NULL, 0, share, "?????",
 373                 cli_credentials_get_username(cli_creds),
 374                 cli_credentials_get_domain(cli_creds),
 375                 cli_credentials_get_password(cli_creds),
 376                 0, 0);
 377         if (!NT_STATUS_IS_OK(status)) {
 378                 PyErr_SetNTSTATUS(status);
 379                 return -1;
 380         }
 381         return 0;
 382 }
 383
 384 static void py_cli_state_dealloc(struct py_cli_state *self)
 385 {
 386         TALLOC_FREE(self->thread_state);
 387         TALLOC_FREE(self->ev);
 388
 389         if (self->cli != NULL) {
 390                 cli_shutdown(self->cli);
 391                 self->cli = NULL;
 392         }
 393         self->ob_type->tp_free((PyObject *)self);
 394 }
 395
 396 static bool py_tevent_req_wait_exc(struct tevent_context *ev,
 397                                    struct tevent_req *req)
 398 {
 399         int ret;
 400
 401         if (req == NULL) {
 402                 PyErr_NoMemory();
 403                 return false;
 404         }
 405         ret = py_tevent_req_wait(ev, req);
 406         if (ret != 0) {
 407                 TALLOC_FREE(req);
 408                 errno = ret;
 409                 PyErr_SetFromErrno(PyExc_RuntimeError);
 410                 return false;
 411         }
 412         return true;
 413 }
 414
 415 static PyObject *py_cli_create(struct py_cli_state *self, PyObject *args,
 416                                PyObject *kwds)
 417 {
 418         char *fname;
 419         unsigned CreateFlags = 0;
 420         unsigned DesiredAccess = FILE_GENERIC_READ;
 421         unsigned FileAttributes = 0;
 422         unsigned ShareAccess = 0;
 423         unsigned CreateDisposition = FILE_OPEN;
 424         unsigned CreateOptions = 0;
 425         unsigned SecurityFlags = 0;
 426         uint16_t fnum;
 427         struct tevent_req *req;
 428         NTSTATUS status;
 429
 430         static const char *kwlist[] = {
 431                 "Name", "CreateFlags", "DesiredAccess", "FileAttributes",
 432                 "ShareAccess", "CreateDisposition", "CreateOptions",
 433                 "SecurityFlags", NULL };
 434
 435         if (!PyArg_ParseTupleAndKeywords(
 436                     args, kwds, "s|IIIIIII", (char **)kwlist,
 437                     &fname, &CreateFlags, &DesiredAccess, &FileAttributes,
 438                     &ShareAccess, &CreateDisposition, &CreateOptions,
 439                     &SecurityFlags)) {
 440                 return NULL;
 441         }
 442
 443         req = cli_ntcreate_send(NULL, self->ev, self->cli, fname, CreateFlags,
 444                                 DesiredAccess, FileAttributes, ShareAccess,
 445                                 CreateDisposition, CreateOptions,
 446                                 SecurityFlags);
 447         if (!py_tevent_req_wait_exc(self->ev, req)) {
 448                 return NULL;
 449         }
 450         status = cli_ntcreate_recv(req, &fnum);
 451         TALLOC_FREE(req);
 452
 453         if (!NT_STATUS_IS_OK(status)) {
 454                 PyErr_SetNTSTATUS(status);
 455                 return NULL;
 456         }
 457         return Py_BuildValue("I", (unsigned)fnum);
 458 }
 459
 460 static PyObject *py_cli_close(struct py_cli_state *self, PyObject *args)
 461 {
 462         struct tevent_req *req;
 463         int fnum;
 464         NTSTATUS status;
 465
 466         if (!PyArg_ParseTuple(args, "i", &fnum)) {
 467                 return NULL;
 468         }
 469
 470         req = cli_close_send(NULL, self->ev, self->cli, fnum);
 471         if (!py_tevent_req_wait_exc(self->ev, req)) {
 472                 return NULL;
 473         }
 474         status = cli_close_recv(req);
 475         TALLOC_FREE(req);
 476
 477         if (!NT_STATUS_IS_OK(status)) {
 478                 PyErr_SetNTSTATUS(status);
 479                 return NULL;
 480         }
 481         Py_INCREF(Py_None);
 482         return Py_None;
 483 }
 484
 485 static PyObject *py_cli_write(struct py_cli_state *self, PyObject *args,
 486                               PyObject *kwds)
 487 {
 488         int fnum;
 489         unsigned mode = 0;
 490         char *buf;
 491         int buflen;
 492         unsigned long long offset;
 493         struct tevent_req *req;
 494         NTSTATUS status;
 495         size_t written;
 496
 497         static const char *kwlist[] = {
 498                 "fnum", "buffer", "offset", "mode", NULL };
 499
 500         if (!PyArg_ParseTupleAndKeywords(
 501                     args, kwds, "Is#K|I", (char **)kwlist,
 502                     &fnum, &buf, &buflen, &offset, &mode)) {
 503                 return NULL;
 504         }
 505
 506         req = cli_write_andx_send(NULL, self->ev, self->cli, fnum, mode,
 507                                   (uint8_t *)buf, offset, buflen);
 508         if (!py_tevent_req_wait_exc(self->ev, req)) {
 509                 return NULL;
 510         }
 511         status = cli_write_andx_recv(req, &written);
 512         TALLOC_FREE(req);
 513
 514         if (!NT_STATUS_IS_OK(status)) {
 515                 PyErr_SetNTSTATUS(status);
 516                 return NULL;
 517         }
 518         return Py_BuildValue("K", (unsigned long long)written);
 519 }
 520
 521 static PyObject *py_cli_read(struct py_cli_state *self, PyObject *args,
 522                              PyObject *kwds)
 523 {
 524         int fnum;
 525         unsigned long long offset;
 526         unsigned size;
 527         struct tevent_req *req;
 528         NTSTATUS status;
 529         uint8_t *buf;
 530         ssize_t buflen;
 531         PyObject *result;
 532
 533         static const char *kwlist[] = {
 534                 "fnum", "offset", "size", NULL };
 535
 536         if (!PyArg_ParseTupleAndKeywords(
 537                     args, kwds, "IKI", (char **)kwlist, &fnum, &offset,
 538                     &size)) {
 539                 return NULL;
 540         }
 541
 542         req = cli_read_andx_send(NULL, self->ev, self->cli, fnum,
 543                                  offset, size);
 544         if (!py_tevent_req_wait_exc(self->ev, req)) {
 545                 return NULL;
 546         }
 547         status = cli_read_andx_recv(req, &buflen, &buf);
 548
 549         if (!NT_STATUS_IS_OK(status)) {
 550                 TALLOC_FREE(req);
 551                 PyErr_SetNTSTATUS(status);
 552                 return NULL;
 553         }
 554         result = Py_BuildValue("s#", (char *)buf, (int)buflen);
 555         TALLOC_FREE(req);
 556         return result;
 557 }
 558
 559 static PyObject *py_cli_ftruncate(struct py_cli_state *self, PyObject *args,
 560                                   PyObject *kwds)
 561 {
 562         int fnum;
 563         unsigned long long size;
 564         struct tevent_req *req;
 565         NTSTATUS status;
 566
 567         static const char *kwlist[] = {
 568                 "fnum", "size", NULL };
 569
 570         if (!PyArg_ParseTupleAndKeywords(
 571                     args, kwds, "IK", (char **)kwlist, &fnum, &size)) {
 572                 return NULL;
 573         }
 574
 575         req = cli_ftruncate_send(NULL, self->ev, self->cli, fnum, size);
 576         if (!py_tevent_req_wait_exc(self->ev, req)) {
 577                 return NULL;
 578         }
 579         status = cli_ftruncate_recv(req);
 580
 581         if (!NT_STATUS_IS_OK(status)) {
 582                 TALLOC_FREE(req);
 583                 PyErr_SetNTSTATUS(status);
 584                 return NULL;
 585         }
 586         Py_INCREF(Py_None);
 587         return Py_None;
 588 }
 589
 590 static PyObject *py_cli_delete_on_close(struct py_cli_state *self,
 591                                         PyObject *args,
 592                                         PyObject *kwds)
 593 {
 594         unsigned fnum, flag;
 595         struct tevent_req *req;
 596         NTSTATUS status;
 597
 598         static const char *kwlist[] = {
 599                 "fnum", "flag", NULL };
 600
 601         if (!PyArg_ParseTupleAndKeywords(
 602                     args, kwds, "II", (char **)kwlist, &fnum, &flag)) {
 603                 return NULL;
 604         }
 605
 606         req = cli_nt_delete_on_close_send(NULL, self->ev, self->cli, fnum,
 607                                           flag);
 608         if (!py_tevent_req_wait_exc(self->ev, req)) {
 609                 return NULL;
 610         }
 611         status = cli_nt_delete_on_close_recv(req);
 612
 613         if (!NT_STATUS_IS_OK(status)) {
 614                 TALLOC_FREE(req);
 615                 PyErr_SetNTSTATUS(status);
 616                 return NULL;
 617         }
 618         Py_INCREF(Py_None);
 619         return Py_None;
 620 }
 621
 622 static PyMethodDef py_cli_state_methods[] = {
 623         { "create", (PyCFunction)py_cli_create, METH_VARARGS|METH_KEYWORDS,
 624           "Open a file" },
 625         { "close", (PyCFunction)py_cli_close, METH_VARARGS,
 626           "Close a file handle" },
 627         { "write", (PyCFunction)py_cli_write, METH_VARARGS|METH_KEYWORDS,
 628           "Write to a file handle" },
 629         { "read", (PyCFunction)py_cli_read, METH_VARARGS|METH_KEYWORDS,
 630           "Read from a file handle" },
 631         { "truncate", (PyCFunction)py_cli_ftruncate,
 632           METH_VARARGS|METH_KEYWORDS,
 633           "Truncate a file" },
 634         { "delete_on_close", (PyCFunction)py_cli_delete_on_close,
 635           METH_VARARGS|METH_KEYWORDS,
 636           "Set/Reset the delete on close flag" },
 637         { NULL, NULL, 0, NULL }
 638 };
 639
 640 static PyTypeObject py_cli_state_type = {
 641         PyObject_HEAD_INIT(NULL)
 642         .tp_name = "libsmb_samba_internal.Conn",
 643         .tp_basicsize = sizeof(struct py_cli_state),
 644         .tp_flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE,
 645         .tp_doc = "libsmb connection",
 646         .tp_new = py_cli_state_new,
 647         .tp_init = (initproc)py_cli_state_init,
 648         .tp_dealloc = (destructor)py_cli_state_dealloc,
 649         .tp_methods = py_cli_state_methods,
 650 };
 651
 652 static PyMethodDef py_libsmb_methods[] = {
 653         { NULL },
 654 };
 655
 656 void initlibsmb_samba_internal(void);
 657 void initlibsmb_samba_internal(void)
 658 {
 659         PyObject *m;
 660
 661         talloc_stackframe();
 662
 663         m = Py_InitModule3("libsmb_samba_internal", py_libsmb_methods,
 664                            "libsmb wrapper");
 665
 666         if (PyType_Ready(&py_cli_state_type) < 0) {
 667                 return;
 668         }
 669         Py_INCREF(&py_cli_state_type);
 670         PyModule_AddObject(m, "Conn", (PyObject *)&py_cli_state_type);
 671 }