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 #endif
  28
  29 #ifdef HAVE_ARPA_INET_H
  30 #include <arpa/inet.h>
  31 #endif
  32
  33 #ifdef HAVE_POLL_H
  34 #include <poll.h>
  35 #endif
  36
  37 #ifdef HAVE_UNISTD_H
  38 #include <unistd.h>
  39 #endif
  40
  41 #ifdef HAVE_SYS_IOCTL_H
  42 #include <sys/ioctl.h>
  43 #endif
  44
  45 #ifdef HAVE_SYS_SOCKET_H
  46 #include <sys/socket.h>
  47 #endif
  48
  49 #ifdef HAVE_NETDB_H
  50 #include <netdb.h>
  51 #endif
  52
  53 #ifdef HAVE_SYS_FILIO_H
  54 #include <sys/filio.h>
  55 #endif
  56
  57 #ifdef HAVE_SYS_SOCKIO_H
  58 #include <sys/sockio.h>
  59 #endif
  60
  61 #include <stdio.h>
  62 #include <stdlib.h>
  63 #include <assert.h>
  64 #include <fcntl.h>
  65 #include <string.h>
  66 #include <errno.h>
  67 #include <sys/types.h>
  68 #include "libnfs-zdr.h"
  69 #include "libnfs.h"
  70 #include "libnfs-raw.h"
  71 #include "libnfs-private.h"
  72 #include "slist.h"
  73
  74 #ifdef WIN32
  75 //has to be included after stdlib!!
  76 #include "win32_errnowrapper.h"
  77 #endif
  78
  79
  80 static int rpc_reconnect_requeue(struct rpc_context *rpc);
  81 static int rpc_connect_sockaddr_async(struct rpc_context *rpc, struct sockaddr_storage *s);
  82
  83 static void set_nonblocking(int fd)
  84 {
  85         int v = 0;
  86 #if defined(WIN32)
  87         long nonblocking=1;
  88         v = ioctl(fd, FIONBIO, &nonblocking);
  89 #else
  90         v = fcntl(fd, F_GETFL, 0);
  91         fcntl(fd, F_SETFL, v | O_NONBLOCK);
  92 #endif //FIXME
  93 }
  94
  95 int rpc_get_fd(struct rpc_context *rpc)
  96 {
  97         assert(rpc->magic == RPC_CONTEXT_MAGIC);
  98
  99         return rpc->fd;
 100 }
 101
 102 int rpc_which_events(struct rpc_context *rpc)
 103 {
 104         int events;
 105
 106         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 107
 108         events = rpc->is_connected ? POLLIN : POLLOUT;
 109
 110         if (rpc->is_udp != 0) {
 111                 /* for udp sockets we only wait for pollin */
 112                 return POLLIN;
 113         }
 114
 115         if (rpc->outqueue) {
 116                 events |= POLLOUT;
 117         }
 118         return events;
 119 }
 120
 121 static int rpc_write_to_socket(struct rpc_context *rpc)
 122 {
 123         int32_t count;
 124
 125         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 126
 127         if (rpc->fd == -1) {
 128                 rpc_set_error(rpc, "trying to write but not connected");
 129                 return -1;
 130         }
 131
 132         while (rpc->outqueue != NULL) {
 133                 int64_t total;
 134
 135                 total = rpc->outqueue->outdata.size;
 136
 137                 count = send(rpc->fd, rpc->outqueue->outdata.data + rpc->outqueue->written, total - rpc->outqueue->written, 0);
 138                 if (count == -1) {
 139                         if (errno == EAGAIN || errno == EWOULDBLOCK) {
 140                                 return 0;
 141                         }
 142                         rpc_set_error(rpc, "Error when writing to socket :%s(%d)", strerror(errno), errno);
 143                         return -1;
 144                 }
 145
 146                 rpc->outqueue->written += count;
 147                 if (rpc->outqueue->written == total) {
 148                         struct rpc_pdu *pdu = rpc->outqueue;
 149
 150                         SLIST_REMOVE(&rpc->outqueue, pdu);
 151                         SLIST_ADD_END(&rpc->waitpdu, pdu);
 152                 }
 153         }
 154         return 0;
 155 }
 156
 157 static int rpc_read_from_socket(struct rpc_context *rpc)
 158 {
 159         int available;
 160         int size;
 161         int pdu_size;
 162         int32_t count;
 163
 164         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 165
 166         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 167
 168         if (ioctl(rpc->fd, FIONREAD, &available) != 0) {
 169                 rpc_set_error(rpc, "Ioctl FIONREAD returned error : %d. Closing socket.", errno);
 170                 return -1;
 171         }
 172
 173         if (available == 0) {
 174                 rpc_set_error(rpc, "Socket has been closed");
 175                 return -1;
 176         }
 177
 178         if (rpc->is_udp) {
 179                 char *buf;
 180                 socklen_t socklen = sizeof(rpc->udp_src);
 181
 182                 buf = malloc(available);
 183                 if (buf == NULL) {
 184                         rpc_set_error(rpc, "Failed to malloc buffer for recvfrom");
 185                         return -1;
 186                 }
 187                 count = recvfrom(rpc->fd, buf, available, MSG_DONTWAIT, (struct sockaddr *)&rpc->udp_src, &socklen);
 188                 if (count < 0) {
 189                         rpc_set_error(rpc, "Failed recvfrom: %s", strerror(errno));
 190                         free(buf);
 191                 }
 192                 if (rpc_process_pdu(rpc, buf, count) != 0) {
 193                         rpc_set_error(rpc, "Invalid/garbage pdu received from server. Ignoring PDU");
 194                         free(buf);
 195                         return -1;
 196                 }
 197                 free(buf);
 198                 return 0;
 199         }
 200
 201         /* read record marker, 4 bytes at the beginning of every pdu */
 202         if (rpc->inbuf == NULL) {
 203                 rpc->insize = 4;
 204                 rpc->inbuf = malloc(rpc->insize);
 205                 if (rpc->inbuf == NULL) {
 206                         rpc_set_error(rpc, "Failed to allocate buffer for record marker, errno:%d. Closing socket.", errno);
 207                         return -1;
 208                 }
 209         }
 210         if (rpc->inpos < 4) {
 211                 size = 4 - rpc->inpos;
 212
 213                 count = recv(rpc->fd, rpc->inbuf + rpc->inpos, size, 0);
 214                 if (count == -1) {
 215                         if (errno == EINTR) {
 216                                 return 0;
 217                         }
 218                         rpc_set_error(rpc, "Read from socket failed, errno:%d. Closing socket.", errno);
 219                         return -1;
 220                 }
 221                 available  -= count;
 222                 rpc->inpos += count;
 223         }
 224
 225         if (available == 0) {
 226                 return 0;
 227         }
 228
 229         pdu_size = rpc_get_pdu_size(rpc->inbuf);
 230         if (rpc->insize < pdu_size) {
 231                 unsigned char *buf;
 232
 233                 buf = malloc(pdu_size);
 234                 if (buf == NULL) {
 235                         rpc_set_error(rpc, "Failed to allocate buffer of %d bytes for pdu, errno:%d. Closing socket.", pdu_size, errno);
 236                         return -1;
 237                 }
 238                 memcpy(buf, rpc->inbuf, rpc->insize);
 239                 free(rpc->inbuf);
 240                 rpc->inbuf  = buf;
 241                 rpc->insize = rpc_get_pdu_size(rpc->inbuf);
 242         }
 243
 244         size = available;
 245         if (size > rpc->insize - rpc->inpos) {
 246                 size = rpc->insize - rpc->inpos;
 247         }
 248
 249         count = recv(rpc->fd, rpc->inbuf + rpc->inpos, size, 0);
 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, port, rc;
 415
 416                 if (portOfs == 0) {
 417                         portOfs = time(NULL) % 400;
 418                 }
 419                 startOfs = portOfs;
 420                 do {
 421                         rc = -1;
 422                         port = htons(firstPort + portOfs);
 423                         portOfs = (portOfs + 1) % portCount;
 424
 425                         /* skip well-known ports */
 426                         if (!getservbyport(port, "tcp")) {
 427                                 memset(&sin, 0, sizeof(sin));
 428                                 sin.sin_port        = port;
 429                                 sin.sin_family      = AF_INET;
 430                                 sin.sin_addr.s_addr = 0;
 431
 432                                 rc = bind(rpc->fd, (struct sockaddr *)&sin, sizeof(struct sockaddr_in));
 433 #if !defined(WIN32)
 434                                 /* we got EACCES, so don't try again */
 435                                 if (rc != 0 && errno == EACCES)
 436                                         break;
 437 #endif
 438                         }
 439                 } while (rc != 0 && portOfs != startOfs);
 440         }
 441
 442         set_nonblocking(rpc->fd);
 443
 444         if (connect(rpc->fd, (struct sockaddr *)s, socksize) != 0 && errno != EINPROGRESS) {
 445                 rpc_set_error(rpc, "connect() to server failed. %s(%d)", strerror(errno), errno);
 446                 return -1;
 447         }
 448
 449         return 0;
 450 }
 451
 452 int rpc_connect_async(struct rpc_context *rpc, const char *server, int port, rpc_cb cb, void *private_data)
 453 {
 454         struct sockaddr_in *sin = (struct sockaddr_in *)&rpc->s;
 455
 456         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 457
 458         if (rpc->fd != -1) {
 459                 rpc_set_error(rpc, "Trying to connect while already connected");
 460                 return -1;
 461         }
 462
 463         if (rpc->is_udp != 0) {
 464                 rpc_set_error(rpc, "Trying to connect on UDP socket");
 465                 return -1;
 466         }
 467
 468         rpc->auto_reconnect = 0;
 469
 470         sin->sin_family = AF_INET;
 471         sin->sin_port   = htons(port);
 472         if (inet_pton(AF_INET, server, &sin->sin_addr) != 1) {
 473                 rpc_set_error(rpc, "Not a valid server ip address");
 474                 return -1;
 475         }
 476
 477
 478         switch (rpc->s.ss_family) {
 479         case AF_INET:
 480 #ifdef HAVE_SOCKADDR_LEN
 481                 sin->sin_len = sizeof(struct sockaddr_in);
 482 #endif
 483                 break;
 484         }
 485
 486         rpc->connect_cb  = cb;
 487         rpc->connect_data = private_data;
 488
 489         if (rpc_connect_sockaddr_async(rpc, &rpc->s) != 0) {
 490                 return -1;
 491         }
 492
 493         return 0;
 494 }
 495
 496 int rpc_disconnect(struct rpc_context *rpc, char *error)
 497 {
 498         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 499
 500         rpc_unset_autoreconnect(rpc);
 501
 502         if (rpc->fd != -1) {
 503                 close(rpc->fd);
 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                 close(rpc->fd);
 536         }
 537         rpc->fd  = -1;
 538
 539         rpc->is_connected = 0;
 540
 541         /* socket is closed so we will not get any replies to any commands
 542          * in flight. Move them all over from the waitpdu queue back to the out queue
 543          */
 544         for (pdu=rpc->waitpdu; pdu; pdu=pdu->next) {
 545                 SLIST_REMOVE(&rpc->waitpdu, pdu);
 546                 SLIST_ADD(&rpc->outqueue, pdu);
 547                 /* we have to re-send the whole pdu again */
 548                 pdu->written = 0;
 549         }
 550
 551         if (rpc->auto_reconnect != 0) {
 552                 rpc->connect_cb  = reconnect_cb;
 553
 554                 if (rpc_connect_sockaddr_async(rpc, &rpc->s) != 0) {
 555                         rpc_error_all_pdus(rpc, "RPC ERROR: Failed to reconnect async");
 556                         return -1;
 557                 }
 558         }
 559
 560         return 0;
 561 }
 562
 563
 564 int rpc_bind_udp(struct rpc_context *rpc, char *addr, int port)
 565 {
 566         struct addrinfo *ai = NULL;
 567         char service[6];
 568
 569         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 570
 571         if (rpc->is_udp == 0) {
 572                 rpc_set_error(rpc, "Cant not bind UDP. Not UDP context");
 573                 return -1;
 574         }
 575
 576         sprintf(service, "%d", port);
 577         if (getaddrinfo(addr, service, NULL, &ai) != 0) {
 578                 rpc_set_error(rpc, "Invalid address:%s. "
 579                         "Can not resolv into IPv4/v6 structure.");
 580                 return -1;
 581         }
 582
 583         switch(ai->ai_family) {
 584         case AF_INET:
 585                 rpc->fd = socket(ai->ai_family, SOCK_DGRAM, 0);
 586                 if (rpc->fd == -1) {
 587                         rpc_set_error(rpc, "Failed to create UDP socket: %s", strerror(errno));
 588                         freeaddrinfo(ai);
 589                         return -1;
 590                 }
 591
 592                 if (bind(rpc->fd, (struct sockaddr *)ai->ai_addr, sizeof(struct sockaddr_in)) != 0) {
 593                         rpc_set_error(rpc, "Failed to bind to UDP socket: %s",strerror(errno));
 594                         freeaddrinfo(ai);
 595                         return -1;
 596                 }
 597                 break;
 598         default:
 599                 rpc_set_error(rpc, "Can not handle UPD sockets of family %d yet", ai->ai_family);
 600                 freeaddrinfo(ai);
 601                 return -1;
 602         }
 603
 604         freeaddrinfo(ai);
 605
 606         return 0;
 607 }
 608
 609 int rpc_set_udp_destination(struct rpc_context *rpc, char *addr, int port, int is_broadcast)
 610 {
 611         struct addrinfo *ai = NULL;
 612         char service[6];
 613
 614         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 615
 616         if (rpc->is_udp == 0) {
 617                 rpc_set_error(rpc, "Can not set destination sockaddr. Not UDP context");
 618                 return -1;
 619         }
 620
 621         sprintf(service, "%d", port);
 622         if (getaddrinfo(addr, service, NULL, &ai) != 0) {
 623                 rpc_set_error(rpc, "Invalid address:%s. "
 624                         "Can not resolv into IPv4/v6 structure.");
 625                 return -1;
 626         }
 627
 628         if (rpc->udp_dest) {
 629                 free(rpc->udp_dest);
 630                 rpc->udp_dest = NULL;
 631         }
 632         rpc->udp_dest = malloc(ai->ai_addrlen);
 633         if (rpc->udp_dest == NULL) {
 634                 rpc_set_error(rpc, "Out of memory. Failed to allocate sockaddr structure");
 635                 freeaddrinfo(ai);
 636                 return -1;
 637         }
 638         memcpy(rpc->udp_dest, ai->ai_addr, ai->ai_addrlen);
 639         freeaddrinfo(ai);
 640
 641         rpc->is_broadcast = is_broadcast;
 642         setsockopt(rpc->fd, SOL_SOCKET, SO_BROADCAST, (char *)&is_broadcast, sizeof(is_broadcast));
 643
 644         return 0;
 645 }
 646
 647 struct sockaddr *rpc_get_recv_sockaddr(struct rpc_context *rpc)
 648 {
 649         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 650
 651         return (struct sockaddr *)&rpc->udp_src;
 652 }
 653
 654 int rpc_queue_length(struct rpc_context *rpc)
 655 {
 656         int i=0;
 657         struct rpc_pdu *pdu;
 658
 659         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 660
 661         for(pdu = rpc->outqueue; pdu; pdu = pdu->next) {
 662                 i++;
 663         }
 664         for(pdu = rpc->waitpdu; pdu; pdu = pdu->next) {
 665                 i++;
 666         }
 667         return i;
 668 }