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         if (ioctl(rpc->fd, FIONREAD, &available) != 0) {
 167                 rpc_set_error(rpc, "Ioctl FIONREAD returned error : %d. Closing socket.", errno);
 168                 return -1;
 169         }
 170
 171         if (available == 0) {
 172                 rpc_set_error(rpc, "Socket has been closed");
 173                 return -1;
 174         }
 175
 176         if (rpc->is_udp) {
 177                 char *buf;
 178                 socklen_t socklen = sizeof(rpc->udp_src);
 179
 180                 buf = malloc(available);
 181                 if (buf == NULL) {
 182                         rpc_set_error(rpc, "Failed to malloc buffer for recvfrom");
 183                         return -1;
 184                 }
 185                 count = recvfrom(rpc->fd, buf, available, MSG_DONTWAIT, (struct sockaddr *)&rpc->udp_src, &socklen);
 186                 if (count < 0) {
 187                         rpc_set_error(rpc, "Failed recvfrom: %s", strerror(errno));
 188                         free(buf);
 189                 }
 190                 if (rpc_process_pdu(rpc, buf, count) != 0) {
 191                         rpc_set_error(rpc, "Invalid/garbage pdu received from server. Ignoring PDU");
 192                         free(buf);
 193                         return -1;
 194                 }
 195                 free(buf);
 196                 return 0;
 197         }
 198
 199         /* read record marker, 4 bytes at the beginning of every pdu */
 200         if (rpc->inbuf == NULL) {
 201                 rpc->insize = 4;
 202                 rpc->inbuf = malloc(rpc->insize);
 203                 if (rpc->inbuf == NULL) {
 204                         rpc_set_error(rpc, "Failed to allocate buffer for record marker, errno:%d. Closing socket.", errno);
 205                         return -1;
 206                 }
 207         }
 208         if (rpc->inpos < 4) {
 209                 size = 4 - rpc->inpos;
 210
 211                 count = recv(rpc->fd, rpc->inbuf + rpc->inpos, size, 0);
 212                 if (count == -1) {
 213                         if (errno == EINTR) {
 214                                 return 0;
 215                         }
 216                         rpc_set_error(rpc, "Read from socket failed, errno:%d. Closing socket.", errno);
 217                         return -1;
 218                 }
 219                 available  -= count;
 220                 rpc->inpos += count;
 221         }
 222
 223         if (available == 0) {
 224                 return 0;
 225         }
 226
 227         pdu_size = rpc_get_pdu_size(rpc->inbuf);
 228         if (rpc->insize < pdu_size) {
 229                 unsigned char *buf;
 230
 231                 buf = malloc(pdu_size);
 232                 if (buf == NULL) {
 233                         rpc_set_error(rpc, "Failed to allocate buffer of %d bytes for pdu, errno:%d. Closing socket.", pdu_size, errno);
 234                         return -1;
 235                 }
 236                 memcpy(buf, rpc->inbuf, rpc->insize);
 237                 free(rpc->inbuf);
 238                 rpc->inbuf  = buf;
 239                 rpc->insize = rpc_get_pdu_size(rpc->inbuf);
 240         }
 241
 242         size = available;
 243         if (size > rpc->insize - rpc->inpos) {
 244                 size = rpc->insize - rpc->inpos;
 245         }
 246
 247         count = recv(rpc->fd, rpc->inbuf + rpc->inpos, size, 0);
 248         if (count == -1) {
 249                 if (errno == EINTR) {
 250                         return 0;
 251                 }
 252                 rpc_set_error(rpc, "Read from socket failed, errno:%d. Closing socket.", errno);
 253                 return -1;
 254         }
 255         available  -= count;
 256         rpc->inpos += count;
 257
 258         if (rpc->inpos == rpc->insize) {
 259                 char *buf = rpc->inbuf;
 260
 261                 rpc->inbuf  = NULL;
 262                 rpc->insize = 0;
 263                 rpc->inpos  = 0;
 264
 265                 if (rpc_process_pdu(rpc, buf, pdu_size) != 0) {
 266                         rpc_set_error(rpc, "Invalid/garbage pdu received from server. Closing socket");
 267                         return -1;
 268                 }
 269                 free(buf);
 270         }
 271
 272         return 0;
 273 }
 274
 275
 276
 277 int rpc_service(struct rpc_context *rpc, int revents)
 278 {
 279         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 280
 281         if (revents & POLLERR) {
 282 #ifdef WIN32
 283                 char err = 0;
 284 #else
 285                 int err = 0;
 286 #endif
 287                 socklen_t err_size = sizeof(err);
 288
 289                 if (getsockopt(rpc->fd, SOL_SOCKET, SO_ERROR,
 290                                 (char *)&err, &err_size) != 0 || err != 0) {
 291                         if (err == 0) {
 292                                 err = errno;
 293                         }
 294                         rpc_set_error(rpc, "rpc_service: socket error "
 295                                                "%s(%d).",
 296                                                strerror(err), err);
 297                 } else {
 298                         rpc_set_error(rpc, "rpc_service: POLLERR, "
 299                                                 "Unknown socket error.");
 300                 }
 301                 if (rpc->connect_cb != NULL) {
 302                         rpc->connect_cb(rpc, RPC_STATUS_ERROR, rpc->error_string, rpc->connect_data);
 303                 }
 304                 return -1;
 305         }
 306         if (revents & POLLHUP) {
 307                 rpc_set_error(rpc, "Socket failed with POLLHUP");
 308                 if (rpc->connect_cb != NULL) {
 309                         rpc->connect_cb(rpc, RPC_STATUS_ERROR, rpc->error_string, rpc->connect_data);
 310                 }
 311                 return -1;
 312         }
 313
 314         if (rpc->is_connected == 0 && rpc->fd != -1 && revents&POLLOUT) {
 315                 int err = 0;
 316                 socklen_t err_size = sizeof(err);
 317
 318                 if (getsockopt(rpc->fd, SOL_SOCKET, SO_ERROR,
 319                                 (char *)&err, &err_size) != 0 || err != 0) {
 320                         if (err == 0) {
 321                                 err = errno;
 322                         }
 323                         rpc_set_error(rpc, "rpc_service: socket error "
 324                                         "%s(%d) while connecting.",
 325                                         strerror(err), err);
 326                         if (rpc->connect_cb != NULL) {
 327                                 rpc->connect_cb(rpc, RPC_STATUS_ERROR,
 328                                         NULL, rpc->connect_data);
 329                         }
 330                         return -1;
 331                 }
 332
 333                 rpc->is_connected = 1;
 334                 if (rpc->connect_cb != NULL) {
 335                         rpc->connect_cb(rpc, RPC_STATUS_SUCCESS, NULL, rpc->connect_data);
 336                 }
 337                 return 0;
 338         }
 339
 340         if (revents & POLLIN) {
 341                 if (rpc_read_from_socket(rpc) != 0) {
 342                         rpc_reconnect_requeue(rpc);
 343                         return 0;
 344                 }
 345         }
 346
 347         if (revents & POLLOUT && rpc->outqueue != NULL) {
 348                 if (rpc_write_to_socket(rpc) != 0) {
 349                         rpc_set_error(rpc, "write to socket failed");
 350                         return -1;
 351                 }
 352         }
 353
 354         return 0;
 355 }
 356
 357 void rpc_set_autoreconnect(struct rpc_context *rpc)
 358 {
 359         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 360
 361         rpc->auto_reconnect = 1;
 362 }
 363
 364 void rpc_unset_autoreconnect(struct rpc_context *rpc)
 365 {
 366         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 367
 368         rpc->auto_reconnect = 0;
 369 }
 370
 371 static int rpc_connect_sockaddr_async(struct rpc_context *rpc, struct sockaddr_storage *s)
 372 {
 373         int socksize;
 374
 375         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 376
 377         switch (s->ss_family) {
 378         case AF_INET:
 379                 socksize = sizeof(struct sockaddr_in);
 380                 rpc->fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
 381                 break;
 382         default:
 383                 rpc_set_error(rpc, "Can not handle AF_FAMILY:%d", s->ss_family);
 384                 return -1;
 385         }
 386
 387         if (rpc->fd == -1) {
 388                 rpc_set_error(rpc, "Failed to open socket");
 389                 return -1;
 390         }
 391
 392         /* Some systems allow you to set capabilities on an executable
 393          * to allow the file to be executed with privilege to bind to
 394          * privileged system ports, even if the user is not root.
 395          *
 396          * Opportunistically try to bind the socket to a low numbered
 397          * system port in the hope that the user is either root or the
 398          * executable has the CAP_NET_BIND_SERVICE.
 399          *
 400          * As soon as we fail the bind() with EACCES we know we will never
 401          * be able to bind to a system port so we terminate the loop.
 402          *
 403          * On linux, use
 404          *    sudo setcap 'cap_net_bind_service=+ep' /path/executable
 405          * to make the executable able to bind to a system port.
 406          *
 407          * On Windows, there is no concept of privileged ports. Thus
 408          * binding will usually succeed.
 409          */
 410         {
 411                 struct sockaddr_in sin;
 412                 static int portOfs = 0;
 413                 const int firstPort = 512;      /* >= 512 according to Sun docs */
 414                 const int portCount = IPPORT_RESERVED - firstPort;
 415                 int startOfs, port, rc;
 416
 417                 if (portOfs == 0) {
 418                         portOfs = time(NULL) % 400;
 419                 }
 420                 startOfs = portOfs;
 421                 do {
 422                         rc = -1;
 423                         port = htons(firstPort + portOfs);
 424                         portOfs = (portOfs + 1) % portCount;
 425
 426                         /* skip well-known ports */
 427                         if (!getservbyport(port, "tcp")) {
 428                                 memset(&sin, 0, sizeof(sin));
 429                                 sin.sin_port        = port;
 430                                 sin.sin_family      = AF_INET;
 431                                 sin.sin_addr.s_addr = 0;
 432
 433                                 rc = bind(rpc->fd, (struct sockaddr *)&sin, sizeof(struct sockaddr_in));
 434 #if !defined(WIN32)
 435                                 /* we got EACCES, so don't try again */
 436                                 if (rc != 0 && errno == EACCES)
 437                                         break;
 438 #endif
 439                         }
 440                 } while (rc != 0 && portOfs != startOfs);
 441         }
 442
 443         set_nonblocking(rpc->fd);
 444
 445         if (connect(rpc->fd, (struct sockaddr *)s, socksize) != 0 && errno != EINPROGRESS) {
 446                 rpc_set_error(rpc, "connect() to server failed. %s(%d)", strerror(errno), errno);
 447                 return -1;
 448         }
 449
 450         return 0;
 451 }
 452
 453 int rpc_connect_async(struct rpc_context *rpc, const char *server, int port, rpc_cb cb, void *private_data)
 454 {
 455         struct sockaddr_in *sin = (struct sockaddr_in *)&rpc->s;
 456
 457         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 458
 459         if (rpc->fd != -1) {
 460                 rpc_set_error(rpc, "Trying to connect while already connected");
 461                 return -1;
 462         }
 463
 464         if (rpc->is_udp != 0) {
 465                 rpc_set_error(rpc, "Trying to connect on UDP socket");
 466                 return -1;
 467         }
 468
 469         rpc->auto_reconnect = 0;
 470
 471         sin->sin_family = AF_INET;
 472         sin->sin_port   = htons(port);
 473         if (inet_pton(AF_INET, server, &sin->sin_addr) != 1) {
 474                 rpc_set_error(rpc, "Not a valid server ip address");
 475                 return -1;
 476         }
 477
 478
 479         switch (rpc->s.ss_family) {
 480         case AF_INET:
 481 #ifdef HAVE_SOCKADDR_LEN
 482                 sin->sin_len = sizeof(struct sockaddr_in);
 483 #endif
 484                 break;
 485         }
 486
 487         rpc->connect_cb  = cb;
 488         rpc->connect_data = private_data;
 489
 490         if (rpc_connect_sockaddr_async(rpc, &rpc->s) != 0) {
 491                 return -1;
 492         }
 493
 494         return 0;
 495 }
 496
 497 int rpc_disconnect(struct rpc_context *rpc, char *error)
 498 {
 499         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 500
 501         rpc_unset_autoreconnect(rpc);
 502
 503         if (rpc->fd != -1) {
 504                 close(rpc->fd);
 505         }
 506         rpc->fd  = -1;
 507
 508         rpc->is_connected = 0;
 509
 510         rpc_error_all_pdus(rpc, error);
 511
 512         return 0;
 513 }
 514
 515 static void reconnect_cb(struct rpc_context *rpc, int status, void *data _U_, void *private_data)
 516 {
 517         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 518
 519         if (status != RPC_STATUS_SUCCESS) {
 520                 rpc_error_all_pdus(rpc, "RPC ERROR: Failed to reconnect async");
 521                 return;
 522         }
 523
 524         rpc->is_connected = 1;
 525         rpc->connect_cb   = NULL;
 526 }
 527
 528 /* disconnect but do not error all PDUs, just move pdus in-flight back to the outqueue and reconnect */
 529 static int rpc_reconnect_requeue(struct rpc_context *rpc)
 530 {
 531         struct rpc_pdu *pdu;
 532
 533         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 534
 535         if (rpc->fd != -1) {
 536                 close(rpc->fd);
 537         }
 538         rpc->fd  = -1;
 539
 540         rpc->is_connected = 0;
 541
 542         /* socket is closed so we will not get any replies to any commands
 543          * in flight. Move them all over from the waitpdu queue back to the out queue
 544          */
 545         for (pdu=rpc->waitpdu; pdu; pdu=pdu->next) {
 546                 SLIST_REMOVE(&rpc->waitpdu, pdu);
 547                 SLIST_ADD(&rpc->outqueue, pdu);
 548                 /* we have to re-send the whole pdu again */
 549                 pdu->written = 0;
 550         }
 551
 552         if (rpc->auto_reconnect != 0) {
 553                 rpc->connect_cb  = reconnect_cb;
 554
 555                 if (rpc_connect_sockaddr_async(rpc, &rpc->s) != 0) {
 556                         rpc_error_all_pdus(rpc, "RPC ERROR: Failed to reconnect async");
 557                         return -1;
 558                 }
 559         }
 560
 561         return 0;
 562 }
 563
 564
 565 int rpc_bind_udp(struct rpc_context *rpc, char *addr, int port)
 566 {
 567         struct addrinfo *ai = NULL;
 568         char service[6];
 569
 570         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 571
 572         if (rpc->is_udp == 0) {
 573                 rpc_set_error(rpc, "Cant not bind UDP. Not UDP context");
 574                 return -1;
 575         }
 576
 577         sprintf(service, "%d", port);
 578         if (getaddrinfo(addr, service, NULL, &ai) != 0) {
 579                 rpc_set_error(rpc, "Invalid address:%s. "
 580                         "Can not resolv into IPv4/v6 structure.");
 581                 return -1;
 582         }
 583
 584         switch(ai->ai_family) {
 585         case AF_INET:
 586                 rpc->fd = socket(ai->ai_family, SOCK_DGRAM, 0);
 587                 if (rpc->fd == -1) {
 588                         rpc_set_error(rpc, "Failed to create UDP socket: %s", strerror(errno));
 589                         freeaddrinfo(ai);
 590                         return -1;
 591                 }
 592
 593                 if (bind(rpc->fd, (struct sockaddr *)ai->ai_addr, sizeof(struct sockaddr_in)) != 0) {
 594                         rpc_set_error(rpc, "Failed to bind to UDP socket: %s",strerror(errno));
 595                         freeaddrinfo(ai);
 596                         return -1;
 597                 }
 598                 break;
 599         default:
 600                 rpc_set_error(rpc, "Can not handle UPD sockets of family %d yet", ai->ai_family);
 601                 freeaddrinfo(ai);
 602                 return -1;
 603         }
 604
 605         freeaddrinfo(ai);
 606
 607         return 0;
 608 }
 609
 610 int rpc_set_udp_destination(struct rpc_context *rpc, char *addr, int port, int is_broadcast)
 611 {
 612         struct addrinfo *ai = NULL;
 613         char service[6];
 614
 615         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 616
 617         if (rpc->is_udp == 0) {
 618                 rpc_set_error(rpc, "Can not set destination sockaddr. Not UDP context");
 619                 return -1;
 620         }
 621
 622         sprintf(service, "%d", port);
 623         if (getaddrinfo(addr, service, NULL, &ai) != 0) {
 624                 rpc_set_error(rpc, "Invalid address:%s. "
 625                         "Can not resolv into IPv4/v6 structure.");
 626                 return -1;
 627         }
 628
 629         if (rpc->udp_dest) {
 630                 free(rpc->udp_dest);
 631                 rpc->udp_dest = NULL;
 632         }
 633         rpc->udp_dest = malloc(ai->ai_addrlen);
 634         if (rpc->udp_dest == NULL) {
 635                 rpc_set_error(rpc, "Out of memory. Failed to allocate sockaddr structure");
 636                 freeaddrinfo(ai);
 637                 return -1;
 638         }
 639         memcpy(rpc->udp_dest, ai->ai_addr, ai->ai_addrlen);
 640         freeaddrinfo(ai);
 641
 642         rpc->is_broadcast = is_broadcast;
 643         setsockopt(rpc->fd, SOL_SOCKET, SO_BROADCAST, (char *)&is_broadcast, sizeof(is_broadcast));
 644
 645         return 0;
 646 }
 647
 648 struct sockaddr *rpc_get_recv_sockaddr(struct rpc_context *rpc)
 649 {
 650         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 651
 652         return (struct sockaddr *)&rpc->udp_src;
 653 }
 654
 655 int rpc_queue_length(struct rpc_context *rpc)
 656 {
 657         int i=0;
 658         struct rpc_pdu *pdu;
 659
 660         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 661
 662         for(pdu = rpc->outqueue; pdu; pdu = pdu->next) {
 663                 i++;
 664         }
 665         for(pdu = rpc->waitpdu; pdu; pdu = pdu->next) {
 666                 i++;
 667         }
 668         return i;
 669 }