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 = ioctl(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                 count = send(rpc->fd, rpc->outqueue->outdata.data + rpc->outqueue->written, total - rpc->outqueue->written, 0);
 122                 if (count == -1) {
 123                         if (errno == EAGAIN || errno == EWOULDBLOCK) {
 124                                 return 0;
 125                         }
 126                         rpc_set_error(rpc, "Error when writing to socket :%s(%d)", strerror(errno), errno);
 127                         return -1;
 128                 }
 129
 130                 rpc->outqueue->written += count;
 131                 if (rpc->outqueue->written == total) {
 132                         struct rpc_pdu *pdu = rpc->outqueue;
 133
 134                         SLIST_REMOVE(&rpc->outqueue, pdu);
 135                         SLIST_ADD_END(&rpc->waitpdu, pdu);
 136                 }
 137         }
 138         return 0;
 139 }
 140
 141 static int rpc_read_from_socket(struct rpc_context *rpc)
 142 {
 143         int available;
 144         int size;
 145         int pdu_size;
 146         int32_t count;
 147
 148         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 149
 150         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 151
 152         if (ioctl(rpc->fd, FIONREAD, &available) != 0) {
 153                 rpc_set_error(rpc, "Ioctl FIONREAD returned error : %d. Closing socket.", errno);
 154                 return -1;
 155         }
 156
 157         if (available == 0) {
 158                 rpc_set_error(rpc, "Socket has been closed");
 159                 return -1;
 160         }
 161
 162         if (rpc->is_udp) {
 163                 char *buf;
 164                 socklen_t socklen = sizeof(rpc->udp_src);
 165
 166                 buf = malloc(available);
 167                 if (buf == NULL) {
 168                         rpc_set_error(rpc, "Failed to malloc buffer for recvfrom");
 169                         return -1;
 170                 }
 171                 count = recvfrom(rpc->fd, buf, available, MSG_DONTWAIT, (struct sockaddr *)&rpc->udp_src, &socklen);
 172                 if (count < 0) {
 173                         rpc_set_error(rpc, "Failed recvfrom: %s", strerror(errno));
 174                         free(buf);
 175                 }
 176                 if (rpc_process_pdu(rpc, buf, count) != 0) {
 177                         rpc_set_error(rpc, "Invalid/garbage pdu received from server. Ignoring PDU");
 178                         free(buf);
 179                         return -1;
 180                 }
 181                 free(buf);
 182                 return 0;
 183         }
 184
 185         /* read record marker, 4 bytes at the beginning of every pdu */
 186         if (rpc->inbuf == NULL) {
 187                 rpc->insize = 4;
 188                 rpc->inbuf = malloc(rpc->insize);
 189                 if (rpc->inbuf == NULL) {
 190                         rpc_set_error(rpc, "Failed to allocate buffer for record marker, errno:%d. Closing socket.", errno);
 191                         return -1;
 192                 }
 193         }
 194         if (rpc->inpos < 4) {
 195                 size = 4 - rpc->inpos;
 196
 197                 count = recv(rpc->fd, rpc->inbuf + rpc->inpos, size, 0);
 198                 if (count == -1) {
 199                         if (errno == EINTR) {
 200                                 return 0;
 201                         }
 202                         rpc_set_error(rpc, "Read from socket failed, errno:%d. Closing socket.", errno);
 203                         return -1;
 204                 }
 205                 available  -= count;
 206                 rpc->inpos += count;
 207         }
 208
 209         if (available == 0) {
 210                 return 0;
 211         }
 212
 213         pdu_size = rpc_get_pdu_size(rpc->inbuf);
 214         if (rpc->insize < pdu_size) {
 215                 unsigned char *buf;
 216
 217                 buf = malloc(pdu_size);
 218                 if (buf == NULL) {
 219                         rpc_set_error(rpc, "Failed to allocate buffer of %d bytes for pdu, errno:%d. Closing socket.", pdu_size, errno);
 220                         return -1;
 221                 }
 222                 memcpy(buf, rpc->inbuf, rpc->insize);
 223                 free(rpc->inbuf);
 224                 rpc->inbuf  = buf;
 225                 rpc->insize = rpc_get_pdu_size(rpc->inbuf);
 226         }
 227
 228         size = available;
 229         if (size > rpc->insize - rpc->inpos) {
 230                 size = rpc->insize - rpc->inpos;
 231         }
 232
 233         count = recv(rpc->fd, rpc->inbuf + rpc->inpos, size, 0);
 234         if (count == -1) {
 235                 if (errno == EINTR) {
 236                         return 0;
 237                 }
 238                 rpc_set_error(rpc, "Read from socket failed, errno:%d. Closing socket.", errno);
 239                 return -1;
 240         }
 241         available  -= count;
 242         rpc->inpos += count;
 243
 244         if (rpc->inpos == rpc->insize) {
 245                 if (rpc_process_pdu(rpc, rpc->inbuf, pdu_size) != 0) {
 246                         rpc_set_error(rpc, "Invalid/garbage pdu received from server. Closing socket");
 247                         return -1;
 248                 }
 249                 free(rpc->inbuf);
 250                 rpc->inbuf  = NULL;
 251                 rpc->insize = 0;
 252                 rpc->inpos  = 0;
 253         }
 254
 255         return 0;
 256 }
 257
 258
 259
 260 int rpc_service(struct rpc_context *rpc, int revents)
 261 {
 262         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 263
 264         if (revents & POLLERR) {
 265 #ifdef WIN32
 266                 char err = 0;
 267 #else
 268                 int err = 0;
 269 #endif
 270                 socklen_t err_size = sizeof(err);
 271
 272                 if (getsockopt(rpc->fd, SOL_SOCKET, SO_ERROR,
 273                                 (char *)&err, &err_size) != 0 || err != 0) {
 274                         if (err == 0) {
 275                                 err = errno;
 276                         }
 277                         rpc_set_error(rpc, "rpc_service: socket error "
 278                                                "%s(%d).",
 279                                                strerror(err), err);
 280                 } else {
 281                         rpc_set_error(rpc, "rpc_service: POLLERR, "
 282                                                 "Unknown socket error.");
 283                 }
 284                 if (rpc->connect_cb != NULL) {
 285                         rpc->connect_cb(rpc, RPC_STATUS_ERROR, rpc->error_string, rpc->connect_data);
 286                 }
 287                 return -1;
 288         }
 289         if (revents & POLLHUP) {
 290                 rpc_set_error(rpc, "Socket failed with POLLHUP");
 291                 if (rpc->connect_cb != NULL) {
 292                         rpc->connect_cb(rpc, RPC_STATUS_ERROR, rpc->error_string, rpc->connect_data);
 293                 }
 294                 return -1;
 295         }
 296
 297         if (rpc->is_connected == 0 && rpc->fd != -1 && revents&POLLOUT) {
 298                 int err = 0;
 299                 socklen_t err_size = sizeof(err);
 300
 301                 if (getsockopt(rpc->fd, SOL_SOCKET, SO_ERROR,
 302                                 (char *)&err, &err_size) != 0 || err != 0) {
 303                         if (err == 0) {
 304                                 err = errno;
 305                         }
 306                         rpc_set_error(rpc, "rpc_service: socket error "
 307                                         "%s(%d) while connecting.",
 308                                         strerror(err), err);
 309                         if (rpc->connect_cb != NULL) {
 310                                 rpc->connect_cb(rpc, RPC_STATUS_ERROR,
 311                                         NULL, rpc->connect_data);
 312                         }
 313                         return -1;
 314                 }
 315
 316                 rpc->is_connected = 1;
 317                 if (rpc->connect_cb != NULL) {
 318                         rpc->connect_cb(rpc, RPC_STATUS_SUCCESS, NULL, rpc->connect_data);
 319                 }
 320                 return 0;
 321         }
 322
 323         if (revents & POLLIN) {
 324                 if (rpc_read_from_socket(rpc) != 0) {
 325                         rpc_reconnect_requeue(rpc);
 326                         return 0;
 327                 }
 328         }
 329
 330         if (revents & POLLOUT && rpc->outqueue != NULL) {
 331                 if (rpc_write_to_socket(rpc) != 0) {
 332                         rpc_set_error(rpc, "write to socket failed");
 333                         return -1;
 334                 }
 335         }
 336
 337         return 0;
 338 }
 339
 340 void rpc_set_autoreconnect(struct rpc_context *rpc)
 341 {
 342         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 343
 344         rpc->auto_reconnect = 1;
 345 }
 346
 347 void rpc_unset_autoreconnect(struct rpc_context *rpc)
 348 {
 349         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 350
 351         rpc->auto_reconnect = 0;
 352 }
 353
 354 static int rpc_connect_sockaddr_async(struct rpc_context *rpc, struct sockaddr_storage *s)
 355 {
 356         int socksize;
 357
 358         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 359
 360         switch (s->ss_family) {
 361         case AF_INET:
 362                 socksize = sizeof(struct sockaddr_in);
 363                 rpc->fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
 364                 break;
 365         default:
 366                 rpc_set_error(rpc, "Can not handle AF_FAMILY:%d", s->ss_family);
 367                 return -1;
 368         }
 369
 370         if (rpc->fd == -1) {
 371                 rpc_set_error(rpc, "Failed to open socket");
 372                 return -1;
 373         }
 374
 375         /* Some systems allow you to set capabilities on an executable
 376          * to allow the file to be executed with privilege to bind to
 377          * privileged system ports, even if the user is not root.
 378          *
 379          * Opportunistically try to bind the socket to a low numbered
 380          * system port in the hope that the user is either root or the
 381          * executable has the CAP_NET_BIND_SERVICE.
 382          *
 383          * As soon as we fail the bind() with EACCES we know we will never
 384          * be able to bind to a system port so we terminate the loop.
 385          *
 386          * On linux, use
 387          *    sudo setcap 'cap_net_bind_service=+ep' /path/executable
 388          * to make the executable able to bind to a system port.
 389          *
 390          * On Windows, there is no concept of privileged ports. Thus
 391          * binding will usually succeed.
 392          */
 393         {
 394                 struct sockaddr_in sin;
 395                 static int portOfs = 0;
 396                 const int firstPort = 512;      /* >= 512 according to Sun docs */
 397                 const int portCount = IPPORT_RESERVED - firstPort;
 398                 int startOfs = portOfs, port, rc;
 399
 400                 do {
 401                         rc = -1;
 402                         port = htons(firstPort + portOfs);
 403                         portOfs = (portOfs + 1) % portCount;
 404
 405                         /* skip well-known ports */
 406                         if (!getservbyport(port, "tcp")) {
 407                                 memset(&sin, 0, sizeof(sin));
 408                                 sin.sin_port        = port;
 409                                 sin.sin_family      = AF_INET;
 410                                 sin.sin_addr.s_addr = 0;
 411
 412                                 rc = bind(rpc->fd, (struct sockaddr *)&sin, sizeof(struct sockaddr_in));
 413 #if !defined(WIN32)
 414                                 /* we got EACCES, so don't try again */
 415                                 if (rc != 0 && errno == EACCES)
 416                                         break;
 417 #endif
 418                         }
 419                 } while (rc != 0 && portOfs != startOfs);
 420         }
 421
 422         set_nonblocking(rpc->fd);
 423
 424         if (connect(rpc->fd, (struct sockaddr *)s, socksize) != 0 && errno != EINPROGRESS) {
 425                 rpc_set_error(rpc, "connect() to server failed. %s(%d)", strerror(errno), errno);
 426                 return -1;
 427         }
 428
 429         return 0;
 430 }
 431
 432 int rpc_connect_async(struct rpc_context *rpc, const char *server, int port, rpc_cb cb, void *private_data)
 433 {
 434         struct sockaddr_in *sin = (struct sockaddr_in *)&rpc->s;
 435
 436         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 437
 438         if (rpc->fd != -1) {
 439                 rpc_set_error(rpc, "Trying to connect while already connected");
 440                 return -1;
 441         }
 442
 443         if (rpc->is_udp != 0) {
 444                 rpc_set_error(rpc, "Trying to connect on UDP socket");
 445                 return -1;
 446         }
 447
 448         rpc->auto_reconnect = 0;
 449
 450         sin->sin_family = AF_INET;
 451         sin->sin_port   = htons(port);
 452         if (inet_pton(AF_INET, server, &sin->sin_addr) != 1) {
 453                 rpc_set_error(rpc, "Not a valid server ip address");
 454                 return -1;
 455         }
 456
 457
 458         switch (rpc->s.ss_family) {
 459         case AF_INET:
 460 #ifdef HAVE_SOCKADDR_LEN
 461                 sin->sin_len = sizeof(struct sockaddr_in);
 462 #endif
 463                 break;
 464         }
 465
 466         rpc->connect_cb  = cb;
 467         rpc->connect_data = private_data;
 468
 469         if (rpc_connect_sockaddr_async(rpc, &rpc->s) != 0) {
 470                 return -1;
 471         }
 472
 473         return 0;
 474 }
 475
 476 int rpc_disconnect(struct rpc_context *rpc, char *error)
 477 {
 478         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 479
 480         rpc_unset_autoreconnect(rpc);
 481
 482         if (rpc->fd != -1) {
 483                 close(rpc->fd);
 484         }
 485         rpc->fd  = -1;
 486
 487         rpc->is_connected = 0;
 488
 489         rpc_error_all_pdus(rpc, error);
 490
 491         return 0;
 492 }
 493
 494 static void reconnect_cb(struct rpc_context *rpc, int status, void *data _U_, void *private_data)
 495 {
 496         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 497
 498         if (status != RPC_STATUS_SUCCESS) {
 499                 rpc_error_all_pdus(rpc, "RPC ERROR: Failed to reconnect async");
 500                 return;
 501         }
 502
 503         rpc->is_connected = 1;
 504         rpc->connect_cb   = NULL;
 505 }
 506
 507 /* disconnect but do not error all PDUs, just move pdus in-flight back to the outqueue and reconnect */
 508 static int rpc_reconnect_requeue(struct rpc_context *rpc)
 509 {
 510         struct rpc_pdu *pdu;
 511
 512         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 513
 514         if (rpc->fd != -1) {
 515                 close(rpc->fd);
 516         }
 517         rpc->fd  = -1;
 518
 519         rpc->is_connected = 0;
 520
 521         /* socket is closed so we will not get any replies to any commands
 522          * in flight. Move them all over from the waitpdu queue back to the out queue
 523          */
 524         for (pdu=rpc->waitpdu; pdu; pdu=pdu->next) {
 525                 SLIST_REMOVE(&rpc->waitpdu, pdu);
 526                 SLIST_ADD(&rpc->outqueue, pdu);
 527                 /* we have to re-send the whole pdu again */
 528                 pdu->written = 0;
 529         }
 530
 531         if (rpc->auto_reconnect != 0) {
 532                 rpc->connect_cb  = reconnect_cb;
 533
 534                 if (rpc_connect_sockaddr_async(rpc, &rpc->s) != 0) {
 535                         rpc_error_all_pdus(rpc, "RPC ERROR: Failed to reconnect async");
 536                         return -1;
 537                 }
 538         }
 539
 540         return 0;
 541 }
 542
 543
 544 int rpc_bind_udp(struct rpc_context *rpc, char *addr, int port)
 545 {
 546         struct addrinfo *ai = NULL;
 547         char service[6];
 548
 549         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 550
 551         if (rpc->is_udp == 0) {
 552                 rpc_set_error(rpc, "Cant not bind UDP. Not UDP context");
 553                 return -1;
 554         }
 555
 556         sprintf(service, "%d", port);
 557         if (getaddrinfo(addr, service, NULL, &ai) != 0) {
 558                 rpc_set_error(rpc, "Invalid address:%s. "
 559                         "Can not resolv into IPv4/v6 structure.");
 560                 return -1;
 561         }
 562
 563         switch(ai->ai_family) {
 564         case AF_INET:
 565                 rpc->fd = socket(ai->ai_family, SOCK_DGRAM, 0);
 566                 if (rpc->fd == -1) {
 567                         rpc_set_error(rpc, "Failed to create UDP socket: %s", strerror(errno));
 568                         freeaddrinfo(ai);
 569                         return -1;
 570                 }
 571
 572                 if (bind(rpc->fd, (struct sockaddr *)ai->ai_addr, sizeof(struct sockaddr_in)) != 0) {
 573                         rpc_set_error(rpc, "Failed to bind to UDP socket: %s",strerror(errno));
 574                         freeaddrinfo(ai);
 575                         return -1;
 576                 }
 577                 break;
 578         default:
 579                 rpc_set_error(rpc, "Can not handle UPD sockets of family %d yet", ai->ai_family);
 580                 freeaddrinfo(ai);
 581                 return -1;
 582         }
 583
 584         freeaddrinfo(ai);
 585
 586         return 0;
 587 }
 588
 589 int rpc_set_udp_destination(struct rpc_context *rpc, char *addr, int port, int is_broadcast)
 590 {
 591         struct addrinfo *ai = NULL;
 592         char service[6];
 593
 594         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 595
 596         if (rpc->is_udp == 0) {
 597                 rpc_set_error(rpc, "Can not set destination sockaddr. Not UDP context");
 598                 return -1;
 599         }
 600
 601         sprintf(service, "%d", port);
 602         if (getaddrinfo(addr, service, NULL, &ai) != 0) {
 603                 rpc_set_error(rpc, "Invalid address:%s. "
 604                         "Can not resolv into IPv4/v6 structure.");
 605                 return -1;
 606         }
 607
 608         if (rpc->udp_dest) {
 609                 free(rpc->udp_dest);
 610                 rpc->udp_dest = NULL;
 611         }
 612         rpc->udp_dest = malloc(ai->ai_addrlen);
 613         if (rpc->udp_dest == NULL) {
 614                 rpc_set_error(rpc, "Out of memory. Failed to allocate sockaddr structure");
 615                 freeaddrinfo(ai);
 616                 return -1;
 617         }
 618         memcpy(rpc->udp_dest, ai->ai_addr, ai->ai_addrlen);
 619         freeaddrinfo(ai);
 620
 621         rpc->is_broadcast = is_broadcast;
 622         setsockopt(rpc->fd, SOL_SOCKET, SO_BROADCAST, (char *)&is_broadcast, sizeof(is_broadcast));
 623
 624         return 0;
 625 }
 626
 627 struct sockaddr *rpc_get_recv_sockaddr(struct rpc_context *rpc)
 628 {
 629         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 630
 631         return (struct sockaddr *)&rpc->udp_src;
 632 }
 633
 634 int rpc_queue_length(struct rpc_context *rpc)
 635 {
 636         int i=0;
 637         struct rpc_pdu *pdu;
 638
 639         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 640
 641         for(pdu = rpc->outqueue; pdu; pdu = pdu->next) {
 642                 i++;
 643         }
 644         for(pdu = rpc->waitpdu; pdu; pdu = pdu->next) {
 645                 i++;
 646         }
 647         return i;
 648 }