lib/socket.c

   1 /*
   2    Copyright (C) 2010 by Ronnie Sahlberg <ronniesahlberg@gmail.com>
   3
   4    This program is free software; you can redistribute it and/or modify
   5    it under the terms of the GNU Lesser General Public License as published by
   6    the Free Software Foundation; either version 2.1 of the License, or
   7    (at your option) any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public License
  15    along with this program; if not, see <http://www.gnu.org/licenses/>.
  16 */
  17 #ifdef HAVE_CONFIG_H
  18 #include "config.h"
  19 #endif
  20
  21 #ifdef AROS
  22 #include "aros_compat.h"
  23 #endif
  24
  25 #ifdef WIN32
  26 #include "win32_compat.h"
  27 #else
  28 #include <arpa/inet.h>
  29 #include <netdb.h>
  30 #endif/*WIN32*/
  31
  32 #ifdef HAVE_POLL_H
  33 #include <poll.h>
  34 #endif
  35
  36 #ifdef HAVE_UNISTD_H
  37 #include <unistd.h>
  38 #endif
  39
  40 #ifdef HAVE_SYS_IOCTL_H
  41 #include <sys/ioctl.h>
  42 #endif
  43
  44 #ifdef HAVE_SYS_SOCKET_H
  45 #include <sys/socket.h>
  46 #endif
  47
  48 #include <stdio.h>
  49 #include <stdlib.h>
  50 #include <assert.h>
  51 #include <fcntl.h>
  52 #include <string.h>
  53 #include <errno.h>
  54 #ifdef HAVE_SYS_FILIO_H
  55 #include <sys/filio.h>
  56 #endif
  57 #ifdef HAVE_SYS_SOCKIO_H
  58 #include <sys/sockio.h>
  59 #endif
  60 #include <sys/types.h>
  61 #include "libnfs-zdr.h"
  62 #include "libnfs.h"
  63 #include "libnfs-raw.h"
  64 #include "libnfs-private.h"
  65 #include "slist.h"
  66
  67 #ifdef WIN32
  68 //has to be included after stdlib!!
  69 #include "win32_errnowrapper.h"
  70 #endif
  71
  72
  73 static int rpc_reconnect_requeue(struct rpc_context *rpc);
  74 static int rpc_connect_sockaddr_async(struct rpc_context *rpc, struct sockaddr_storage *s);
  75
  76 static void set_nonblocking(int fd)
  77 {
  78         int v = 0;
  79 #if defined(WIN32)
  80         long nonblocking=1;
  81         v = ioctl(fd, FIONBIO, &nonblocking);
  82 #else
  83         v = fcntl(fd, F_GETFL, 0);
  84         fcntl(fd, F_SETFL, v | O_NONBLOCK);
  85 #endif //FIXME
  86 }
  87
  88 int rpc_get_fd(struct rpc_context *rpc)
  89 {
  90         assert(rpc->magic == RPC_CONTEXT_MAGIC);
  91
  92         return rpc->fd;
  93 }
  94
  95 int rpc_which_events(struct rpc_context *rpc)
  96 {
  97         int events;
  98
  99         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 100
 101         events = rpc->is_connected ? POLLIN : POLLOUT;
 102
 103         if (rpc->is_udp != 0) {
 104                 /* for udp sockets we only wait for pollin */
 105                 return POLLIN;
 106         }
 107
 108         if (rpc->outqueue) {
 109                 events |= POLLOUT;
 110         }
 111         return events;
 112 }
 113
 114 static int rpc_write_to_socket(struct rpc_context *rpc)
 115 {
 116         int32_t count;
 117
 118         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 119
 120         if (rpc->fd == -1) {
 121                 rpc_set_error(rpc, "trying to write but not connected");
 122                 return -1;
 123         }
 124
 125         while (rpc->outqueue != NULL) {
 126                 int64_t total;
 127
 128                 total = rpc->outqueue->outdata.size;
 129
 130                 count = send(rpc->fd, rpc->outqueue->outdata.data + rpc->outqueue->written, total - rpc->outqueue->written, 0);
 131                 if (count == -1) {
 132                         if (errno == EAGAIN || errno == EWOULDBLOCK) {
 133                                 return 0;
 134                         }
 135                         rpc_set_error(rpc, "Error when writing to socket :%s(%d)", strerror(errno), errno);
 136                         return -1;
 137                 }
 138
 139                 rpc->outqueue->written += count;
 140                 if (rpc->outqueue->written == total) {
 141                         struct rpc_pdu *pdu = rpc->outqueue;
 142
 143                         SLIST_REMOVE(&rpc->outqueue, pdu);
 144                         SLIST_ADD_END(&rpc->waitpdu, pdu);
 145                 }
 146         }
 147         return 0;
 148 }
 149
 150 static int rpc_read_from_socket(struct rpc_context *rpc)
 151 {
 152         int available;
 153         int size;
 154         int pdu_size;
 155         int32_t count;
 156
 157         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 158
 159         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 160
 161         if (ioctl(rpc->fd, FIONREAD, &available) != 0) {
 162                 rpc_set_error(rpc, "Ioctl FIONREAD returned error : %d. Closing socket.", errno);
 163                 return -1;
 164         }
 165
 166         if (available == 0) {
 167                 rpc_set_error(rpc, "Socket has been closed");
 168                 return -1;
 169         }
 170
 171         if (rpc->is_udp) {
 172                 char *buf;
 173                 socklen_t socklen = sizeof(rpc->udp_src);
 174
 175                 buf = malloc(available);
 176                 if (buf == NULL) {
 177                         rpc_set_error(rpc, "Failed to malloc buffer for recvfrom");
 178                         return -1;
 179                 }
 180                 count = recvfrom(rpc->fd, buf, available, MSG_DONTWAIT, (struct sockaddr *)&rpc->udp_src, &socklen);
 181                 if (count < 0) {
 182                         rpc_set_error(rpc, "Failed recvfrom: %s", strerror(errno));
 183                         free(buf);
 184                 }
 185                 if (rpc_process_pdu(rpc, buf, count) != 0) {
 186                         rpc_set_error(rpc, "Invalid/garbage pdu received from server. Ignoring PDU");
 187                         free(buf);
 188                         return -1;
 189                 }
 190                 free(buf);
 191                 return 0;
 192         }
 193
 194         /* read record marker, 4 bytes at the beginning of every pdu */
 195         if (rpc->inbuf == NULL) {
 196                 rpc->insize = 4;
 197                 rpc->inbuf = malloc(rpc->insize);
 198                 if (rpc->inbuf == NULL) {
 199                         rpc_set_error(rpc, "Failed to allocate buffer for record marker, errno:%d. Closing socket.", errno);
 200                         return -1;
 201                 }
 202         }
 203         if (rpc->inpos < 4) {
 204                 size = 4 - rpc->inpos;
 205
 206                 count = recv(rpc->fd, rpc->inbuf + rpc->inpos, size, 0);
 207                 if (count == -1) {
 208                         if (errno == EINTR) {
 209                                 return 0;
 210                         }
 211                         rpc_set_error(rpc, "Read from socket failed, errno:%d. Closing socket.", errno);
 212                         return -1;
 213                 }
 214                 available  -= count;
 215                 rpc->inpos += count;
 216         }
 217
 218         if (available == 0) {
 219                 return 0;
 220         }
 221
 222         pdu_size = rpc_get_pdu_size(rpc->inbuf);
 223         if (rpc->insize < pdu_size) {
 224                 unsigned char *buf;
 225
 226                 buf = malloc(pdu_size);
 227                 if (buf == NULL) {
 228                         rpc_set_error(rpc, "Failed to allocate buffer of %d bytes for pdu, errno:%d. Closing socket.", pdu_size, errno);
 229                         return -1;
 230                 }
 231                 memcpy(buf, rpc->inbuf, rpc->insize);
 232                 free(rpc->inbuf);
 233                 rpc->inbuf  = buf;
 234                 rpc->insize = rpc_get_pdu_size(rpc->inbuf);
 235         }
 236
 237         size = available;
 238         if (size > rpc->insize - rpc->inpos) {
 239                 size = rpc->insize - rpc->inpos;
 240         }
 241
 242         count = recv(rpc->fd, rpc->inbuf + rpc->inpos, size, 0);
 243         if (count == -1) {
 244                 if (errno == EINTR) {
 245                         return 0;
 246                 }
 247                 rpc_set_error(rpc, "Read from socket failed, errno:%d. Closing socket.", errno);
 248                 return -1;
 249         }
 250         available  -= count;
 251         rpc->inpos += count;
 252
 253         if (rpc->inpos == rpc->insize) {
 254                 if (rpc_process_pdu(rpc, rpc->inbuf, pdu_size) != 0) {
 255                         rpc_set_error(rpc, "Invalid/garbage pdu received from server. Closing socket");
 256                         return -1;
 257                 }
 258                 free(rpc->inbuf);
 259                 rpc->inbuf  = NULL;
 260                 rpc->insize = 0;
 261                 rpc->inpos  = 0;
 262         }
 263
 264         return 0;
 265 }
 266
 267
 268
 269 int rpc_service(struct rpc_context *rpc, int revents)
 270 {
 271         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 272
 273         if (revents & POLLERR) {
 274 #ifdef WIN32
 275                 char err = 0;
 276 #else
 277                 int err = 0;
 278 #endif
 279                 socklen_t err_size = sizeof(err);
 280
 281                 if (getsockopt(rpc->fd, SOL_SOCKET, SO_ERROR,
 282                                 (char *)&err, &err_size) != 0 || err != 0) {
 283                         if (err == 0) {
 284                                 err = errno;
 285                         }
 286                         rpc_set_error(rpc, "rpc_service: socket error "
 287                                                "%s(%d).",
 288                                                strerror(err), err);
 289                 } else {
 290                         rpc_set_error(rpc, "rpc_service: POLLERR, "
 291                                                 "Unknown socket error.");
 292                 }
 293                 if (rpc->connect_cb != NULL) {
 294                         rpc->connect_cb(rpc, RPC_STATUS_ERROR, rpc->error_string, rpc->connect_data);
 295                 }
 296                 return -1;
 297         }
 298         if (revents & POLLHUP) {
 299                 rpc_set_error(rpc, "Socket failed with POLLHUP");
 300                 if (rpc->connect_cb != NULL) {
 301                         rpc->connect_cb(rpc, RPC_STATUS_ERROR, rpc->error_string, rpc->connect_data);
 302                 }
 303                 return -1;
 304         }
 305
 306         if (rpc->is_connected == 0 && rpc->fd != -1 && revents&POLLOUT) {
 307                 int err = 0;
 308                 socklen_t err_size = sizeof(err);
 309
 310                 if (getsockopt(rpc->fd, SOL_SOCKET, SO_ERROR,
 311                                 (char *)&err, &err_size) != 0 || err != 0) {
 312                         if (err == 0) {
 313                                 err = errno;
 314                         }
 315                         rpc_set_error(rpc, "rpc_service: socket error "
 316                                         "%s(%d) while connecting.",
 317                                         strerror(err), err);
 318                         if (rpc->connect_cb != NULL) {
 319                                 rpc->connect_cb(rpc, RPC_STATUS_ERROR,
 320                                         NULL, rpc->connect_data);
 321                         }
 322                         return -1;
 323                 }
 324
 325                 rpc->is_connected = 1;
 326                 if (rpc->connect_cb != NULL) {
 327                         rpc->connect_cb(rpc, RPC_STATUS_SUCCESS, NULL, rpc->connect_data);
 328                 }
 329                 return 0;
 330         }
 331
 332         if (revents & POLLIN) {
 333                 if (rpc_read_from_socket(rpc) != 0) {
 334                         rpc_reconnect_requeue(rpc);
 335                         return 0;
 336                 }
 337         }
 338
 339         if (revents & POLLOUT && rpc->outqueue != NULL) {
 340                 if (rpc_write_to_socket(rpc) != 0) {
 341                         rpc_set_error(rpc, "write to socket failed");
 342                         return -1;
 343                 }
 344         }
 345
 346         return 0;
 347 }
 348
 349 void rpc_set_autoreconnect(struct rpc_context *rpc)
 350 {
 351         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 352
 353         rpc->auto_reconnect = 1;
 354 }
 355
 356 void rpc_unset_autoreconnect(struct rpc_context *rpc)
 357 {
 358         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 359
 360         rpc->auto_reconnect = 0;
 361 }
 362
 363 static int rpc_connect_sockaddr_async(struct rpc_context *rpc, struct sockaddr_storage *s)
 364 {
 365         int socksize;
 366
 367         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 368
 369         switch (s->ss_family) {
 370         case AF_INET:
 371                 socksize = sizeof(struct sockaddr_in);
 372                 rpc->fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
 373                 break;
 374         default:
 375                 rpc_set_error(rpc, "Can not handle AF_FAMILY:%d", s->ss_family);
 376                 return -1;
 377         }
 378
 379         if (rpc->fd == -1) {
 380                 rpc_set_error(rpc, "Failed to open socket");
 381                 return -1;
 382         }
 383
 384         /* Some systems allow you to set capabilities on an executable
 385          * to allow the file to be executed with privilege to bind to
 386          * privileged system ports, even if the user is not root.
 387          *
 388          * Opportunistically try to bind the socket to a low numbered
 389          * system port in the hope that the user is either root or the
 390          * executable has the CAP_NET_BIND_SERVICE.
 391          *
 392          * As soon as we fail the bind() with EACCES we know we will never
 393          * be able to bind to a system port so we terminate the loop.
 394          *
 395          * On linux, use
 396          *    sudo setcap 'cap_net_bind_service=+ep' /path/executable
 397          * to make the executable able to bind to a system port.
 398          *
 399          * On Windows, there is no concept of privileged ports. Thus
 400          * binding will usually succeed.
 401          */
 402         {
 403                 struct sockaddr_in sin;
 404                 static int portOfs = 0;
 405                 const int firstPort = 512;      /* >= 512 according to Sun docs */
 406                 const int portCount = IPPORT_RESERVED - firstPort;
 407                 int startOfs, port, rc;
 408
 409                 if (portOfs == 0) {
 410                         portOfs = time(NULL) % 400;
 411                 }
 412                 startOfs = portOfs;
 413                 do {
 414                         rc = -1;
 415                         port = htons(firstPort + portOfs);
 416                         portOfs = (portOfs + 1) % portCount;
 417
 418                         /* skip well-known ports */
 419                         if (!getservbyport(port, "tcp")) {
 420                                 memset(&sin, 0, sizeof(sin));
 421                                 sin.sin_port        = port;
 422                                 sin.sin_family      = AF_INET;
 423                                 sin.sin_addr.s_addr = 0;
 424
 425                                 rc = bind(rpc->fd, (struct sockaddr *)&sin, sizeof(struct sockaddr_in));
 426 #if !defined(WIN32)
 427                                 /* we got EACCES, so don't try again */
 428                                 if (rc != 0 && errno == EACCES)
 429                                         break;
 430 #endif
 431                         }
 432                 } while (rc != 0 && portOfs != startOfs);
 433         }
 434
 435         set_nonblocking(rpc->fd);
 436
 437         if (connect(rpc->fd, (struct sockaddr *)s, socksize) != 0 && errno != EINPROGRESS) {
 438                 rpc_set_error(rpc, "connect() to server failed. %s(%d)", strerror(errno), errno);
 439                 return -1;
 440         }
 441
 442         return 0;
 443 }
 444
 445 int rpc_connect_async(struct rpc_context *rpc, const char *server, int port, rpc_cb cb, void *private_data)
 446 {
 447         struct sockaddr_in *sin = (struct sockaddr_in *)&rpc->s;
 448
 449         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 450
 451         if (rpc->fd != -1) {
 452                 rpc_set_error(rpc, "Trying to connect while already connected");
 453                 return -1;
 454         }
 455
 456         if (rpc->is_udp != 0) {
 457                 rpc_set_error(rpc, "Trying to connect on UDP socket");
 458                 return -1;
 459         }
 460
 461         rpc->auto_reconnect = 0;
 462
 463         sin->sin_family = AF_INET;
 464         sin->sin_port   = htons(port);
 465         if (inet_pton(AF_INET, server, &sin->sin_addr) != 1) {
 466                 rpc_set_error(rpc, "Not a valid server ip address");
 467                 return -1;
 468         }
 469
 470
 471         switch (rpc->s.ss_family) {
 472         case AF_INET:
 473 #ifdef HAVE_SOCKADDR_LEN
 474                 sin->sin_len = sizeof(struct sockaddr_in);
 475 #endif
 476                 break;
 477         }
 478
 479         rpc->connect_cb  = cb;
 480         rpc->connect_data = private_data;
 481
 482         if (rpc_connect_sockaddr_async(rpc, &rpc->s) != 0) {
 483                 return -1;
 484         }
 485
 486         return 0;
 487 }
 488
 489 int rpc_disconnect(struct rpc_context *rpc, char *error)
 490 {
 491         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 492
 493         rpc_unset_autoreconnect(rpc);
 494
 495         if (rpc->fd != -1) {
 496                 close(rpc->fd);
 497         }
 498         rpc->fd  = -1;
 499
 500         rpc->is_connected = 0;
 501
 502         rpc_error_all_pdus(rpc, error);
 503
 504         return 0;
 505 }
 506
 507 static void reconnect_cb(struct rpc_context *rpc, int status, void *data _U_, void *private_data)
 508 {
 509         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 510
 511         if (status != RPC_STATUS_SUCCESS) {
 512                 rpc_error_all_pdus(rpc, "RPC ERROR: Failed to reconnect async");
 513                 return;
 514         }
 515
 516         rpc->is_connected = 1;
 517         rpc->connect_cb   = NULL;
 518 }
 519
 520 /* disconnect but do not error all PDUs, just move pdus in-flight back to the outqueue and reconnect */
 521 static int rpc_reconnect_requeue(struct rpc_context *rpc)
 522 {
 523         struct rpc_pdu *pdu;
 524
 525         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 526
 527         if (rpc->fd != -1) {
 528                 close(rpc->fd);
 529         }
 530         rpc->fd  = -1;
 531
 532         rpc->is_connected = 0;
 533
 534         /* socket is closed so we will not get any replies to any commands
 535          * in flight. Move them all over from the waitpdu queue back to the out queue
 536          */
 537         for (pdu=rpc->waitpdu; pdu; pdu=pdu->next) {
 538                 SLIST_REMOVE(&rpc->waitpdu, pdu);
 539                 SLIST_ADD(&rpc->outqueue, pdu);
 540                 /* we have to re-send the whole pdu again */
 541                 pdu->written = 0;
 542         }
 543
 544         if (rpc->auto_reconnect != 0) {
 545                 rpc->connect_cb  = reconnect_cb;
 546
 547                 if (rpc_connect_sockaddr_async(rpc, &rpc->s) != 0) {
 548                         rpc_error_all_pdus(rpc, "RPC ERROR: Failed to reconnect async");
 549                         return -1;
 550                 }
 551         }
 552
 553         return 0;
 554 }
 555
 556
 557 int rpc_bind_udp(struct rpc_context *rpc, char *addr, int port)
 558 {
 559         struct addrinfo *ai = NULL;
 560         char service[6];
 561
 562         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 563
 564         if (rpc->is_udp == 0) {
 565                 rpc_set_error(rpc, "Cant not bind UDP. Not UDP context");
 566                 return -1;
 567         }
 568
 569         sprintf(service, "%d", port);
 570         if (getaddrinfo(addr, service, NULL, &ai) != 0) {
 571                 rpc_set_error(rpc, "Invalid address:%s. "
 572                         "Can not resolv into IPv4/v6 structure.");
 573                 return -1;
 574         }
 575
 576         switch(ai->ai_family) {
 577         case AF_INET:
 578                 rpc->fd = socket(ai->ai_family, SOCK_DGRAM, 0);
 579                 if (rpc->fd == -1) {
 580                         rpc_set_error(rpc, "Failed to create UDP socket: %s", strerror(errno));
 581                         freeaddrinfo(ai);
 582                         return -1;
 583                 }
 584
 585                 if (bind(rpc->fd, (struct sockaddr *)ai->ai_addr, sizeof(struct sockaddr_in)) != 0) {
 586                         rpc_set_error(rpc, "Failed to bind to UDP socket: %s",strerror(errno));
 587                         freeaddrinfo(ai);
 588                         return -1;
 589                 }
 590                 break;
 591         default:
 592                 rpc_set_error(rpc, "Can not handle UPD sockets of family %d yet", ai->ai_family);
 593                 freeaddrinfo(ai);
 594                 return -1;
 595         }
 596
 597         freeaddrinfo(ai);
 598
 599         return 0;
 600 }
 601
 602 int rpc_set_udp_destination(struct rpc_context *rpc, char *addr, int port, int is_broadcast)
 603 {
 604         struct addrinfo *ai = NULL;
 605         char service[6];
 606
 607         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 608
 609         if (rpc->is_udp == 0) {
 610                 rpc_set_error(rpc, "Can not set destination sockaddr. Not UDP context");
 611                 return -1;
 612         }
 613
 614         sprintf(service, "%d", port);
 615         if (getaddrinfo(addr, service, NULL, &ai) != 0) {
 616                 rpc_set_error(rpc, "Invalid address:%s. "
 617                         "Can not resolv into IPv4/v6 structure.");
 618                 return -1;
 619         }
 620
 621         if (rpc->udp_dest) {
 622                 free(rpc->udp_dest);
 623                 rpc->udp_dest = NULL;
 624         }
 625         rpc->udp_dest = malloc(ai->ai_addrlen);
 626         if (rpc->udp_dest == NULL) {
 627                 rpc_set_error(rpc, "Out of memory. Failed to allocate sockaddr structure");
 628                 freeaddrinfo(ai);
 629                 return -1;
 630         }
 631         memcpy(rpc->udp_dest, ai->ai_addr, ai->ai_addrlen);
 632         freeaddrinfo(ai);
 633
 634         rpc->is_broadcast = is_broadcast;
 635         setsockopt(rpc->fd, SOL_SOCKET, SO_BROADCAST, (char *)&is_broadcast, sizeof(is_broadcast));
 636
 637         return 0;
 638 }
 639
 640 struct sockaddr *rpc_get_recv_sockaddr(struct rpc_context *rpc)
 641 {
 642         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 643
 644         return (struct sockaddr *)&rpc->udp_src;
 645 }
 646
 647 int rpc_queue_length(struct rpc_context *rpc)
 648 {
 649         int i=0;
 650         struct rpc_pdu *pdu;
 651
 652         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 653
 654         for(pdu = rpc->outqueue; pdu; pdu = pdu->next) {
 655                 i++;
 656         }
 657         for(pdu = rpc->waitpdu; pdu; pdu = pdu->next) {
 658                 i++;
 659         }
 660         return i;
 661 }