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 WIN32
  18 #include "win32_compat.h"
  19 #else
  20 #include <unistd.h>
  21 #include <arpa/inet.h>
  22 #include <sys/ioctl.h>
  23 #include <sys/socket.h>
  24 #include <netdb.h>
  25 #endif/*WIN32*/
  26
  27 #ifdef HAVE_CONFIG_H
  28 #include "config.h"
  29 #endif
  30
  31 #ifdef AROS
  32 #include "aros_compat.h"
  33 #endif
  34
  35 #ifdef HAVE_POLL_H
  36 #include <poll.h>
  37 #endif
  38
  39 #include <stdio.h>
  40 #include <stdlib.h>
  41 #include <assert.h>
  42 #include <fcntl.h>
  43 #include <string.h>
  44 #include <errno.h>
  45 #ifdef HAVE_SYS_FILIO_H
  46 #include <sys/filio.h>
  47 #endif
  48 #ifdef HAVE_SYS_SOCKIO_H
  49 #include <sys/sockio.h>
  50 #endif
  51 #include <sys/types.h>
  52 #include "libnfs-zdr.h"
  53 #include "libnfs.h"
  54 #include "libnfs-raw.h"
  55 #include "libnfs-private.h"
  56 #include "slist.h"
  57
  58 #ifdef WIN32
  59 //has to be included after stdlib!!
  60 #include "win32_errnowrapper.h"
  61 #endif
  62
  63
  64 static int rpc_reconnect_requeue(struct rpc_context *rpc);
  65 static int rpc_connect_sockaddr_async(struct rpc_context *rpc, struct sockaddr_storage *s);
  66
  67 static void set_nonblocking(int fd)
  68 {
  69         int v = 0;
  70 #if defined(WIN32)
  71         long nonblocking=1;
  72         v = ioctlsocket(fd, FIONBIO,&nonblocking);
  73 #else
  74         v = fcntl(fd, F_GETFL, 0);
  75         fcntl(fd, F_SETFL, v | O_NONBLOCK);
  76 #endif //FIXME
  77 }
  78
  79 int rpc_get_fd(struct rpc_context *rpc)
  80 {
  81         assert(rpc->magic == RPC_CONTEXT_MAGIC);
  82
  83         return rpc->fd;
  84 }
  85
  86 int rpc_which_events(struct rpc_context *rpc)
  87 {
  88         int events;
  89
  90         assert(rpc->magic == RPC_CONTEXT_MAGIC);
  91
  92         events = rpc->is_connected ? POLLIN : POLLOUT;
  93
  94         if (rpc->is_udp != 0) {
  95                 /* for udp sockets we only wait for pollin */
  96                 return POLLIN;
  97         }
  98
  99         if (rpc->outqueue) {
 100                 events |= POLLOUT;
 101         }
 102         return events;
 103 }
 104
 105 static int rpc_write_to_socket(struct rpc_context *rpc)
 106 {
 107         int32_t count;
 108
 109         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 110
 111         if (rpc->fd == -1) {
 112                 rpc_set_error(rpc, "trying to write but not connected");
 113                 return -1;
 114         }
 115
 116         while (rpc->outqueue != NULL) {
 117                 int64_t total;
 118
 119                 total = rpc->outqueue->outdata.size;
 120
 121 #if defined(WIN32)
 122                 count = send(rpc->fd, rpc->outqueue->outdata.data + rpc->outqueue->written, total - rpc->outqueue->written, 0);
 123 #else
 124                 count = write(rpc->fd, rpc->outqueue->outdata.data + rpc->outqueue->written, total - rpc->outqueue->written);
 125 #endif
 126                 if (count == -1) {
 127                         if (errno == EAGAIN || errno == EWOULDBLOCK) {
 128                                 return 0;
 129                         }
 130                         rpc_set_error(rpc, "Error when writing to socket :%s(%d)", strerror(errno), errno);
 131                         return -1;
 132                 }
 133
 134                 rpc->outqueue->written += count;
 135                 if (rpc->outqueue->written == total) {
 136                         struct rpc_pdu *pdu = rpc->outqueue;
 137
 138                         SLIST_REMOVE(&rpc->outqueue, pdu);
 139                         SLIST_ADD_END(&rpc->waitpdu, pdu);
 140                 }
 141         }
 142         return 0;
 143 }
 144
 145 static int rpc_read_from_socket(struct rpc_context *rpc)
 146 {
 147         int available;
 148         int size;
 149         int pdu_size;
 150         int32_t count;
 151
 152         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 153
 154         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 155
 156 #if defined(WIN32)
 157         if (ioctlsocket(rpc->fd, FIONREAD, &available) != 0) {
 158 #else
 159         if (ioctl(rpc->fd, FIONREAD, &available) != 0) {
 160 #endif
 161                 rpc_set_error(rpc, "Ioctl FIONREAD returned error : %d. Closing socket.", errno);
 162                 return -1;
 163         }
 164
 165         if (available == 0) {
 166                 rpc_set_error(rpc, "Socket has been closed");
 167                 return -1;
 168         }
 169
 170         if (rpc->is_udp) {
 171                 char *buf;
 172                 socklen_t socklen = sizeof(rpc->udp_src);
 173
 174                 buf = malloc(available);
 175                 if (buf == NULL) {
 176                         rpc_set_error(rpc, "Failed to malloc buffer for recvfrom");
 177                         return -1;
 178                 }
 179                 count = recvfrom(rpc->fd, buf, available, MSG_DONTWAIT, (struct sockaddr *)&rpc->udp_src, &socklen);
 180                 if (count < 0) {
 181                         rpc_set_error(rpc, "Failed recvfrom: %s", strerror(errno));
 182                         free(buf);
 183                 }
 184                 if (rpc_process_pdu(rpc, buf, count) != 0) {
 185                         rpc_set_error(rpc, "Invalid/garbage pdu received from server. Ignoring PDU");
 186                         free(buf);
 187                         return -1;
 188                 }
 189                 free(buf);
 190                 return 0;
 191         }
 192
 193         /* read record marker, 4 bytes at the beginning of every pdu */
 194         if (rpc->inbuf == NULL) {
 195                 rpc->insize = 4;
 196                 rpc->inbuf = malloc(rpc->insize);
 197                 if (rpc->inbuf == NULL) {
 198                         rpc_set_error(rpc, "Failed to allocate buffer for record marker, errno:%d. Closing socket.", errno);
 199                         return -1;
 200                 }
 201         }
 202         if (rpc->inpos < 4) {
 203                 size = 4 - rpc->inpos;
 204
 205 #if defined(WIN32)
 206                 count = recv(rpc->fd, rpc->inbuf + rpc->inpos, size, 0);
 207 #else
 208                 count = read(rpc->fd, rpc->inbuf + rpc->inpos, size);
 209 #endif
 210                 if (count == -1) {
 211                         if (errno == EINTR) {
 212                                 return 0;
 213                         }
 214                         rpc_set_error(rpc, "Read from socket failed, errno:%d. Closing socket.", errno);
 215                         return -1;
 216                 }
 217                 available  -= count;
 218                 rpc->inpos += count;
 219         }
 220
 221         if (available == 0) {
 222                 return 0;
 223         }
 224
 225         pdu_size = rpc_get_pdu_size(rpc->inbuf);
 226         if (rpc->insize < pdu_size) {
 227                 unsigned char *buf;
 228
 229                 buf = malloc(pdu_size);
 230                 if (buf == NULL) {
 231                         rpc_set_error(rpc, "Failed to allocate buffer of %d bytes for pdu, errno:%d. Closing socket.", pdu_size, errno);
 232                         return -1;
 233                 }
 234                 memcpy(buf, rpc->inbuf, rpc->insize);
 235                 free(rpc->inbuf);
 236                 rpc->inbuf  = buf;
 237                 rpc->insize = rpc_get_pdu_size(rpc->inbuf);
 238         }
 239
 240         size = available;
 241         if (size > rpc->insize - rpc->inpos) {
 242                 size = rpc->insize - rpc->inpos;
 243         }
 244
 245 #if defined(WIN32)
 246         count = recv(rpc->fd, rpc->inbuf + rpc->inpos, size, 0);
 247 #else
 248         count = read(rpc->fd, rpc->inbuf + rpc->inpos, size);
 249 #endif
 250         if (count == -1) {
 251                 if (errno == EINTR) {
 252                         return 0;
 253                 }
 254                 rpc_set_error(rpc, "Read from socket failed, errno:%d. Closing socket.", errno);
 255                 return -1;
 256         }
 257         available  -= count;
 258         rpc->inpos += count;
 259
 260         if (rpc->inpos == rpc->insize) {
 261                 if (rpc_process_pdu(rpc, rpc->inbuf, pdu_size) != 0) {
 262                         rpc_set_error(rpc, "Invalid/garbage pdu received from server. Closing socket");
 263                         return -1;
 264                 }
 265                 free(rpc->inbuf);
 266                 rpc->inbuf  = NULL;
 267                 rpc->insize = 0;
 268                 rpc->inpos  = 0;
 269         }
 270
 271         return 0;
 272 }
 273
 274
 275
 276 int rpc_service(struct rpc_context *rpc, int revents)
 277 {
 278         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 279
 280         if (revents & POLLERR) {
 281 #ifdef WIN32
 282                 char err = 0;
 283 #else
 284                 int err = 0;
 285 #endif
 286                 socklen_t err_size = sizeof(err);
 287
 288                 if (getsockopt(rpc->fd, SOL_SOCKET, SO_ERROR,
 289                                 (char *)&err, &err_size) != 0 || err != 0) {
 290                         if (err == 0) {
 291                                 err = errno;
 292                         }
 293                         rpc_set_error(rpc, "rpc_service: socket error "
 294                                                "%s(%d).",
 295                                                strerror(err), err);
 296                 } else {
 297                         rpc_set_error(rpc, "rpc_service: POLLERR, "
 298                                                 "Unknown socket error.");
 299                 }
 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         if (revents & POLLHUP) {
 306                 rpc_set_error(rpc, "Socket failed with POLLHUP");
 307                 if (rpc->connect_cb != NULL) {
 308                         rpc->connect_cb(rpc, RPC_STATUS_ERROR, rpc->error_string, rpc->connect_data);
 309                 }
 310                 return -1;
 311         }
 312
 313         if (rpc->is_connected == 0 && rpc->fd != -1 && revents&POLLOUT) {
 314                 int err = 0;
 315                 socklen_t err_size = sizeof(err);
 316
 317                 if (getsockopt(rpc->fd, SOL_SOCKET, SO_ERROR,
 318                                 (char *)&err, &err_size) != 0 || err != 0) {
 319                         if (err == 0) {
 320                                 err = errno;
 321                         }
 322                         rpc_set_error(rpc, "rpc_service: socket error "
 323                                         "%s(%d) while connecting.",
 324                                         strerror(err), err);
 325                         if (rpc->connect_cb != NULL) {
 326                                 rpc->connect_cb(rpc, RPC_STATUS_ERROR,
 327                                         NULL, rpc->connect_data);
 328                         }
 329                         return -1;
 330                 }
 331
 332                 rpc->is_connected = 1;
 333                 if (rpc->connect_cb != NULL) {
 334                         rpc->connect_cb(rpc, RPC_STATUS_SUCCESS, NULL, rpc->connect_data);
 335                 }
 336                 return 0;
 337         }
 338
 339         if (revents & POLLIN) {
 340                 if (rpc_read_from_socket(rpc) != 0) {
 341                         rpc_reconnect_requeue(rpc);
 342                         return 0;
 343                 }
 344         }
 345
 346         if (revents & POLLOUT && rpc->outqueue != NULL) {
 347                 if (rpc_write_to_socket(rpc) != 0) {
 348                         rpc_set_error(rpc, "write to socket failed");
 349                         return -1;
 350                 }
 351         }
 352
 353         return 0;
 354 }
 355
 356 void rpc_set_autoreconnect(struct rpc_context *rpc)
 357 {
 358         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 359
 360         rpc->auto_reconnect = 1;
 361 }
 362
 363 void rpc_unset_autoreconnect(struct rpc_context *rpc)
 364 {
 365         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 366
 367         rpc->auto_reconnect = 0;
 368 }
 369
 370 static int rpc_connect_sockaddr_async(struct rpc_context *rpc, struct sockaddr_storage *s)
 371 {
 372         int socksize;
 373
 374         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 375
 376         switch (s->ss_family) {
 377         case AF_INET:
 378                 socksize = sizeof(struct sockaddr_in);
 379                 rpc->fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
 380                 break;
 381         default:
 382                 rpc_set_error(rpc, "Can not handle AF_FAMILY:%d", s->ss_family);
 383                 return -1;
 384         }
 385
 386         if (rpc->fd == -1) {
 387                 rpc_set_error(rpc, "Failed to open socket");
 388                 return -1;
 389         }
 390
 391         /* Some systems allow you to set capabilities on an executable
 392          * to allow the file to be executed with privilege to bind to
 393          * privileged system ports, even if the user is not root.
 394          *
 395          * Opportunistically try to bind the socket to a low numbered
 396          * system port in the hope that the user is either root or the
 397          * executable has the CAP_NET_BIND_SERVICE.
 398          *
 399          * As soon as we fail the bind() with EACCES we know we will never
 400          * be able to bind to a system port so we terminate the loop.
 401          *
 402          * On linux, use
 403          *    sudo setcap 'cap_net_bind_service=+ep' /path/executable
 404          * to make the executable able to bind to a system port.
 405          *
 406          * On Windows, there is no concept of privileged ports. Thus
 407          * binding will usually succeed.
 408          */
 409         {
 410                 struct sockaddr_in sin;
 411                 static int portOfs = 0;
 412                 const int firstPort = 512;      /* >= 512 according to Sun docs */
 413                 const int portCount = IPPORT_RESERVED - firstPort;
 414                 int startOfs = portOfs, port, rc;
 415
 416                 do {
 417                         rc = -1;
 418                         port = htons(firstPort + portOfs);
 419                         portOfs = (portOfs + 1) % portCount;
 420
 421                         /* skip well-known ports */
 422                         if (!getservbyport(port, "tcp")) {
 423                                 memset(&sin, 0, sizeof(sin));
 424                                 sin.sin_port        = port;
 425                                 sin.sin_family      = AF_INET;
 426                                 sin.sin_addr.s_addr = 0;
 427
 428                                 rc = bind(rpc->fd, (struct sockaddr *)&sin, sizeof(struct sockaddr_in));
 429 #if !defined(WIN32)
 430                                 /* we got EACCES, so don't try again */
 431                                 if (rc != 0 && errno == EACCES)
 432                                         break;
 433 #endif
 434                         }
 435                 } while (rc != 0 && portOfs != startOfs);
 436         }
 437
 438         set_nonblocking(rpc->fd);
 439
 440         if (connect(rpc->fd, (struct sockaddr *)s, socksize) != 0 && errno != EINPROGRESS) {
 441                 rpc_set_error(rpc, "connect() to server failed. %s(%d)", strerror(errno), errno);
 442                 return -1;
 443         }
 444
 445         return 0;
 446 }
 447
 448 int rpc_connect_async(struct rpc_context *rpc, const char *server, int port, rpc_cb cb, void *private_data)
 449 {
 450         struct sockaddr_in *sin = (struct sockaddr_in *)&rpc->s;
 451
 452         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 453
 454         if (rpc->fd != -1) {
 455                 rpc_set_error(rpc, "Trying to connect while already connected");
 456                 return -1;
 457         }
 458
 459         if (rpc->is_udp != 0) {
 460                 rpc_set_error(rpc, "Trying to connect on UDP socket");
 461                 return -1;
 462         }
 463
 464         rpc->auto_reconnect = 0;
 465
 466         sin->sin_family = AF_INET;
 467         sin->sin_port   = htons(port);
 468         if (inet_pton(AF_INET, server, &sin->sin_addr) != 1) {
 469                 rpc_set_error(rpc, "Not a valid server ip address");
 470                 return -1;
 471         }
 472
 473
 474         switch (rpc->s.ss_family) {
 475         case AF_INET:
 476 #ifdef HAVE_SOCKADDR_LEN
 477                 sin->sin_len = sizeof(struct sockaddr_in);
 478 #endif
 479                 break;
 480         }
 481
 482         rpc->connect_cb  = cb;
 483         rpc->connect_data = private_data;
 484
 485         if (rpc_connect_sockaddr_async(rpc, &rpc->s) != 0) {
 486                 return -1;
 487         }
 488
 489         return 0;
 490 }
 491
 492 int rpc_disconnect(struct rpc_context *rpc, char *error)
 493 {
 494         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 495
 496         rpc_unset_autoreconnect(rpc);
 497
 498         if (rpc->fd != -1) {
 499 #if defined(WIN32)
 500                 closesocket(rpc->fd);
 501 #else
 502                 close(rpc->fd);
 503 #endif
 504         }
 505         rpc->fd  = -1;
 506
 507         rpc->is_connected = 0;
 508
 509         rpc_error_all_pdus(rpc, error);
 510
 511         return 0;
 512 }
 513
 514 static void reconnect_cb(struct rpc_context *rpc, int status, void *data _U_, void *private_data)
 515 {
 516         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 517
 518         if (status != RPC_STATUS_SUCCESS) {
 519                 rpc_error_all_pdus(rpc, "RPC ERROR: Failed to reconnect async");
 520                 return;
 521         }
 522
 523         rpc->is_connected = 1;
 524         rpc->connect_cb   = NULL;
 525 }
 526
 527 /* disconnect but do not error all PDUs, just move pdus in-flight back to the outqueue and reconnect */
 528 static int rpc_reconnect_requeue(struct rpc_context *rpc)
 529 {
 530         struct rpc_pdu *pdu;
 531
 532         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 533
 534         if (rpc->fd != -1) {
 535 #if defined(WIN32)
 536                 closesocket(rpc->fd);
 537 #else
 538                 close(rpc->fd);
 539 #endif
 540         }
 541         rpc->fd  = -1;
 542
 543         rpc->is_connected = 0;
 544
 545         /* socket is closed so we will not get any replies to any commands
 546          * in flight. Move them all over from the waitpdu queue back to the out queue
 547          */
 548         for (pdu=rpc->waitpdu; pdu; pdu=pdu->next) {
 549                 SLIST_REMOVE(&rpc->waitpdu, pdu);
 550                 SLIST_ADD(&rpc->outqueue, pdu);
 551                 /* we have to re-send the whole pdu again */
 552                 pdu->written = 0;
 553         }
 554
 555         if (rpc->auto_reconnect != 0) {
 556                 rpc->connect_cb  = reconnect_cb;
 557
 558                 if (rpc_connect_sockaddr_async(rpc, &rpc->s) != 0) {
 559                         rpc_error_all_pdus(rpc, "RPC ERROR: Failed to reconnect async");
 560                         return -1;
 561                 }
 562         }
 563
 564         return 0;
 565 }
 566
 567
 568 int rpc_bind_udp(struct rpc_context *rpc, char *addr, int port)
 569 {
 570         struct addrinfo *ai = NULL;
 571         char service[6];
 572
 573         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 574
 575         if (rpc->is_udp == 0) {
 576                 rpc_set_error(rpc, "Cant not bind UDP. Not UDP context");
 577                 return -1;
 578         }
 579
 580         sprintf(service, "%d", port);
 581         if (getaddrinfo(addr, service, NULL, &ai) != 0) {
 582                 rpc_set_error(rpc, "Invalid address:%s. "
 583                         "Can not resolv into IPv4/v6 structure.");
 584                 return -1;
 585         }
 586
 587         switch(ai->ai_family) {
 588         case AF_INET:
 589                 rpc->fd = socket(ai->ai_family, SOCK_DGRAM, 0);
 590                 if (rpc->fd == -1) {
 591                         rpc_set_error(rpc, "Failed to create UDP socket: %s", strerror(errno));
 592                         freeaddrinfo(ai);
 593                         return -1;
 594                 }
 595
 596                 if (bind(rpc->fd, (struct sockaddr *)ai->ai_addr, sizeof(struct sockaddr_in)) != 0) {
 597                         rpc_set_error(rpc, "Failed to bind to UDP socket: %s",strerror(errno));
 598                         freeaddrinfo(ai);
 599                         return -1;
 600                 }
 601                 break;
 602         default:
 603                 rpc_set_error(rpc, "Can not handle UPD sockets of family %d yet", ai->ai_family);
 604                 freeaddrinfo(ai);
 605                 return -1;
 606         }
 607
 608         freeaddrinfo(ai);
 609
 610         return 0;
 611 }
 612
 613 int rpc_set_udp_destination(struct rpc_context *rpc, char *addr, int port, int is_broadcast)
 614 {
 615         struct addrinfo *ai = NULL;
 616         char service[6];
 617
 618         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 619
 620         if (rpc->is_udp == 0) {
 621                 rpc_set_error(rpc, "Can not set destination sockaddr. Not UDP context");
 622                 return -1;
 623         }
 624
 625         sprintf(service, "%d", port);
 626         if (getaddrinfo(addr, service, NULL, &ai) != 0) {
 627                 rpc_set_error(rpc, "Invalid address:%s. "
 628                         "Can not resolv into IPv4/v6 structure.");
 629                 return -1;
 630         }
 631
 632         if (rpc->udp_dest) {
 633                 free(rpc->udp_dest);
 634                 rpc->udp_dest = NULL;
 635         }
 636         rpc->udp_dest = malloc(ai->ai_addrlen);
 637         if (rpc->udp_dest == NULL) {
 638                 rpc_set_error(rpc, "Out of memory. Failed to allocate sockaddr structure");
 639                 freeaddrinfo(ai);
 640                 return -1;
 641         }
 642         memcpy(rpc->udp_dest, ai->ai_addr, ai->ai_addrlen);
 643         freeaddrinfo(ai);
 644
 645         rpc->is_broadcast = is_broadcast;
 646         setsockopt(rpc->fd, SOL_SOCKET, SO_BROADCAST, (char *)&is_broadcast, sizeof(is_broadcast));
 647
 648         return 0;
 649 }
 650
 651 struct sockaddr *rpc_get_recv_sockaddr(struct rpc_context *rpc)
 652 {
 653         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 654
 655         return (struct sockaddr *)&rpc->udp_src;
 656 }
 657
 658 int rpc_queue_length(struct rpc_context *rpc)
 659 {
 660         int i=0;
 661         struct rpc_pdu *pdu;
 662
 663         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 664
 665         for(pdu = rpc->outqueue; pdu; pdu = pdu->next) {
 666                 i++;
 667         }
 668         for(pdu = rpc->waitpdu; pdu; pdu = pdu->next) {
 669                 i++;
 670         }
 671         return i;
 672 }