lib/socket.c

   1 /*
   2    Copyright (C) 2010 by Ronnie Sahlberg <ronniesahlberg@gmail.com>
   3
   4    This program is free software; you can redistribute it and/or modify
   5    it under the terms of the GNU Lesser General Public License as published by
   6    the Free Software Foundation; either version 2.1 of the License, or
   7    (at your option) any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public License
  15    along with this program; if not, see <http://www.gnu.org/licenses/>.
  16 */
  17 #ifdef HAVE_CONFIG_H
  18 #include "config.h"
  19 #endif
  20
  21 #ifdef AROS
  22 #include "aros_compat.h"
  23 #endif
  24
  25 #ifdef WIN32
  26 #include "win32_compat.h"
  27 #else
  28 #include <arpa/inet.h>
  29 #endif/*WIN32*/
  30
  31 #ifdef HAVE_POLL_H
  32 #include <poll.h>
  33 #endif
  34
  35 #ifdef HAVE_UNISTD_H
  36 #include <unistd.h>
  37 #endif
  38
  39 #ifdef HAVE_SYS_IOCTL_H
  40 #include <sys/ioctl.h>
  41 #endif
  42
  43 #ifdef HAVE_SYS_SOCKET_H
  44 #include <sys/socket.h>
  45 #endif
  46
  47 #ifdef HAVE_NETDB_H
  48 #include <netdb.h>
  49 #endif
  50
  51 #ifdef HAVE_SYS_FILIO_H
  52 #include <sys/filio.h>
  53 #endif
  54
  55 #ifdef HAVE_SYS_SOCKIO_H
  56 #include <sys/sockio.h>
  57 #endif
  58
  59 #include <stdio.h>
  60 #include <stdlib.h>
  61 #include <assert.h>
  62 #include <fcntl.h>
  63 #include <string.h>
  64 #include <errno.h>
  65 #include <sys/types.h>
  66 #include "libnfs-zdr.h"
  67 #include "libnfs.h"
  68 #include "libnfs-raw.h"
  69 #include "libnfs-private.h"
  70 #include "slist.h"
  71
  72 #ifdef WIN32
  73 //has to be included after stdlib!!
  74 #include "win32_errnowrapper.h"
  75 #endif
  76
  77
  78 static int rpc_reconnect_requeue(struct rpc_context *rpc);
  79 static int rpc_connect_sockaddr_async(struct rpc_context *rpc, struct sockaddr_storage *s);
  80
  81 static void set_nonblocking(int fd)
  82 {
  83         int v = 0;
  84 #if defined(WIN32)
  85         long nonblocking=1;
  86         v = ioctl(fd, FIONBIO, &nonblocking);
  87 #else
  88         v = fcntl(fd, F_GETFL, 0);
  89         fcntl(fd, F_SETFL, v | O_NONBLOCK);
  90 #endif //FIXME
  91 }
  92
  93 int rpc_get_fd(struct rpc_context *rpc)
  94 {
  95         assert(rpc->magic == RPC_CONTEXT_MAGIC);
  96
  97         return rpc->fd;
  98 }
  99
 100 int rpc_which_events(struct rpc_context *rpc)
 101 {
 102         int events;
 103
 104         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 105
 106         events = rpc->is_connected ? POLLIN : POLLOUT;
 107
 108         if (rpc->is_udp != 0) {
 109                 /* for udp sockets we only wait for pollin */
 110                 return POLLIN;
 111         }
 112
 113         if (rpc->outqueue) {
 114                 events |= POLLOUT;
 115         }
 116         return events;
 117 }
 118
 119 static int rpc_write_to_socket(struct rpc_context *rpc)
 120 {
 121         int32_t count;
 122
 123         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 124
 125         if (rpc->fd == -1) {
 126                 rpc_set_error(rpc, "trying to write but not connected");
 127                 return -1;
 128         }
 129
 130         while (rpc->outqueue != NULL) {
 131                 int64_t total;
 132
 133                 total = rpc->outqueue->outdata.size;
 134
 135                 count = send(rpc->fd, rpc->outqueue->outdata.data + rpc->outqueue->written, total - rpc->outqueue->written, 0);
 136                 if (count == -1) {
 137                         if (errno == EAGAIN || errno == EWOULDBLOCK) {
 138                                 return 0;
 139                         }
 140                         rpc_set_error(rpc, "Error when writing to socket :%s(%d)", strerror(errno), errno);
 141                         return -1;
 142                 }
 143
 144                 rpc->outqueue->written += count;
 145                 if (rpc->outqueue->written == total) {
 146                         struct rpc_pdu *pdu = rpc->outqueue;
 147
 148                         SLIST_REMOVE(&rpc->outqueue, pdu);
 149                         SLIST_ADD_END(&rpc->waitpdu, pdu);
 150                 }
 151         }
 152         return 0;
 153 }
 154
 155 static int rpc_read_from_socket(struct rpc_context *rpc)
 156 {
 157         int available;
 158         int size;
 159         int pdu_size;
 160         int32_t count;
 161
 162         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 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                 if (rpc_process_pdu(rpc, rpc->inbuf, pdu_size) != 0) {
 260                         rpc_set_error(rpc, "Invalid/garbage pdu received from server. Closing socket");
 261                         return -1;
 262                 }
 263                 free(rpc->inbuf);
 264                 rpc->inbuf  = NULL;
 265                 rpc->insize = 0;
 266                 rpc->inpos  = 0;
 267         }
 268
 269         return 0;
 270 }
 271
 272
 273
 274 int rpc_service(struct rpc_context *rpc, int revents)
 275 {
 276         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 277
 278         if (revents & POLLERR) {
 279 #ifdef WIN32
 280                 char err = 0;
 281 #else
 282                 int err = 0;
 283 #endif
 284                 socklen_t err_size = sizeof(err);
 285
 286                 if (getsockopt(rpc->fd, SOL_SOCKET, SO_ERROR,
 287                                 (char *)&err, &err_size) != 0 || err != 0) {
 288                         if (err == 0) {
 289                                 err = errno;
 290                         }
 291                         rpc_set_error(rpc, "rpc_service: socket error "
 292                                                "%s(%d).",
 293                                                strerror(err), err);
 294                 } else {
 295                         rpc_set_error(rpc, "rpc_service: POLLERR, "
 296                                                 "Unknown socket error.");
 297                 }
 298                 if (rpc->connect_cb != NULL) {
 299                         rpc->connect_cb(rpc, RPC_STATUS_ERROR, rpc->error_string, rpc->connect_data);
 300                 }
 301                 return -1;
 302         }
 303         if (revents & POLLHUP) {
 304                 rpc_set_error(rpc, "Socket failed with POLLHUP");
 305                 if (rpc->connect_cb != NULL) {
 306                         rpc->connect_cb(rpc, RPC_STATUS_ERROR, rpc->error_string, rpc->connect_data);
 307                 }
 308                 return -1;
 309         }
 310
 311         if (rpc->is_connected == 0 && rpc->fd != -1 && revents&POLLOUT) {
 312                 int err = 0;
 313                 socklen_t err_size = sizeof(err);
 314
 315                 if (getsockopt(rpc->fd, SOL_SOCKET, SO_ERROR,
 316                                 (char *)&err, &err_size) != 0 || err != 0) {
 317                         if (err == 0) {
 318                                 err = errno;
 319                         }
 320                         rpc_set_error(rpc, "rpc_service: socket error "
 321                                         "%s(%d) while connecting.",
 322                                         strerror(err), err);
 323                         if (rpc->connect_cb != NULL) {
 324                                 rpc->connect_cb(rpc, RPC_STATUS_ERROR,
 325                                         NULL, rpc->connect_data);
 326                         }
 327                         return -1;
 328                 }
 329
 330                 rpc->is_connected = 1;
 331                 if (rpc->connect_cb != NULL) {
 332                         rpc->connect_cb(rpc, RPC_STATUS_SUCCESS, NULL, rpc->connect_data);
 333                 }
 334                 return 0;
 335         }
 336
 337         if (revents & POLLIN) {
 338                 if (rpc_read_from_socket(rpc) != 0) {
 339                         rpc_reconnect_requeue(rpc);
 340                         return 0;
 341                 }
 342         }
 343
 344         if (revents & POLLOUT && rpc->outqueue != NULL) {
 345                 if (rpc_write_to_socket(rpc) != 0) {
 346                         rpc_set_error(rpc, "write to socket failed");
 347                         return -1;
 348                 }
 349         }
 350
 351         return 0;
 352 }
 353
 354 void rpc_set_autoreconnect(struct rpc_context *rpc)
 355 {
 356         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 357
 358         rpc->auto_reconnect = 1;
 359 }
 360
 361 void rpc_unset_autoreconnect(struct rpc_context *rpc)
 362 {
 363         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 364
 365         rpc->auto_reconnect = 0;
 366 }
 367
 368 static int rpc_connect_sockaddr_async(struct rpc_context *rpc, struct sockaddr_storage *s)
 369 {
 370         int socksize;
 371
 372         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 373
 374         switch (s->ss_family) {
 375         case AF_INET:
 376                 socksize = sizeof(struct sockaddr_in);
 377                 rpc->fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
 378                 break;
 379         default:
 380                 rpc_set_error(rpc, "Can not handle AF_FAMILY:%d", s->ss_family);
 381                 return -1;
 382         }
 383
 384         if (rpc->fd == -1) {
 385                 rpc_set_error(rpc, "Failed to open socket");
 386                 return -1;
 387         }
 388
 389         /* Some systems allow you to set capabilities on an executable
 390          * to allow the file to be executed with privilege to bind to
 391          * privileged system ports, even if the user is not root.
 392          *
 393          * Opportunistically try to bind the socket to a low numbered
 394          * system port in the hope that the user is either root or the
 395          * executable has the CAP_NET_BIND_SERVICE.
 396          *
 397          * As soon as we fail the bind() with EACCES we know we will never
 398          * be able to bind to a system port so we terminate the loop.
 399          *
 400          * On linux, use
 401          *    sudo setcap 'cap_net_bind_service=+ep' /path/executable
 402          * to make the executable able to bind to a system port.
 403          *
 404          * On Windows, there is no concept of privileged ports. Thus
 405          * binding will usually succeed.
 406          */
 407         {
 408                 struct sockaddr_in sin;
 409                 static int portOfs = 0;
 410                 const int firstPort = 512;      /* >= 512 according to Sun docs */
 411                 const int portCount = IPPORT_RESERVED - firstPort;
 412                 int startOfs, port, rc;
 413
 414                 if (portOfs == 0) {
 415                         portOfs = time(NULL) % 400;
 416                 }
 417                 startOfs = portOfs;
 418                 do {
 419                         rc = -1;
 420                         port = htons(firstPort + portOfs);
 421                         portOfs = (portOfs + 1) % portCount;
 422
 423                         /* skip well-known ports */
 424                         if (!getservbyport(port, "tcp")) {
 425                                 memset(&sin, 0, sizeof(sin));
 426                                 sin.sin_port        = port;
 427                                 sin.sin_family      = AF_INET;
 428                                 sin.sin_addr.s_addr = 0;
 429
 430                                 rc = bind(rpc->fd, (struct sockaddr *)&sin, sizeof(struct sockaddr_in));
 431 #if !defined(WIN32)
 432                                 /* we got EACCES, so don't try again */
 433                                 if (rc != 0 && errno == EACCES)
 434                                         break;
 435 #endif
 436                         }
 437                 } while (rc != 0 && portOfs != startOfs);
 438         }
 439
 440         set_nonblocking(rpc->fd);
 441
 442         if (connect(rpc->fd, (struct sockaddr *)s, socksize) != 0 && errno != EINPROGRESS) {
 443                 rpc_set_error(rpc, "connect() to server failed. %s(%d)", strerror(errno), errno);
 444                 return -1;
 445         }
 446
 447         return 0;
 448 }
 449
 450 int rpc_connect_async(struct rpc_context *rpc, const char *server, int port, rpc_cb cb, void *private_data)
 451 {
 452         struct sockaddr_in *sin = (struct sockaddr_in *)&rpc->s;
 453
 454         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 455
 456         if (rpc->fd != -1) {
 457                 rpc_set_error(rpc, "Trying to connect while already connected");
 458                 return -1;
 459         }
 460
 461         if (rpc->is_udp != 0) {
 462                 rpc_set_error(rpc, "Trying to connect on UDP socket");
 463                 return -1;
 464         }
 465
 466         rpc->auto_reconnect = 0;
 467
 468         sin->sin_family = AF_INET;
 469         sin->sin_port   = htons(port);
 470         if (inet_pton(AF_INET, server, &sin->sin_addr) != 1) {
 471                 rpc_set_error(rpc, "Not a valid server ip address");
 472                 return -1;
 473         }
 474
 475
 476         switch (rpc->s.ss_family) {
 477         case AF_INET:
 478 #ifdef HAVE_SOCKADDR_LEN
 479                 sin->sin_len = sizeof(struct sockaddr_in);
 480 #endif
 481                 break;
 482         }
 483
 484         rpc->connect_cb  = cb;
 485         rpc->connect_data = private_data;
 486
 487         if (rpc_connect_sockaddr_async(rpc, &rpc->s) != 0) {
 488                 return -1;
 489         }
 490
 491         return 0;
 492 }
 493
 494 int rpc_disconnect(struct rpc_context *rpc, char *error)
 495 {
 496         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 497
 498         rpc_unset_autoreconnect(rpc);
 499
 500         if (rpc->fd != -1) {
 501                 close(rpc->fd);
 502         }
 503         rpc->fd  = -1;
 504
 505         rpc->is_connected = 0;
 506
 507         rpc_error_all_pdus(rpc, error);
 508
 509         return 0;
 510 }
 511
 512 static void reconnect_cb(struct rpc_context *rpc, int status, void *data _U_, void *private_data)
 513 {
 514         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 515
 516         if (status != RPC_STATUS_SUCCESS) {
 517                 rpc_error_all_pdus(rpc, "RPC ERROR: Failed to reconnect async");
 518                 return;
 519         }
 520
 521         rpc->is_connected = 1;
 522         rpc->connect_cb   = NULL;
 523 }
 524
 525 /* disconnect but do not error all PDUs, just move pdus in-flight back to the outqueue and reconnect */
 526 static int rpc_reconnect_requeue(struct rpc_context *rpc)
 527 {
 528         struct rpc_pdu *pdu;
 529
 530         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 531
 532         if (rpc->fd != -1) {
 533                 close(rpc->fd);
 534         }
 535         rpc->fd  = -1;
 536
 537         rpc->is_connected = 0;
 538
 539         /* socket is closed so we will not get any replies to any commands
 540          * in flight. Move them all over from the waitpdu queue back to the out queue
 541          */
 542         for (pdu=rpc->waitpdu; pdu; pdu=pdu->next) {
 543                 SLIST_REMOVE(&rpc->waitpdu, pdu);
 544                 SLIST_ADD(&rpc->outqueue, pdu);
 545                 /* we have to re-send the whole pdu again */
 546                 pdu->written = 0;
 547         }
 548
 549         if (rpc->auto_reconnect != 0) {
 550                 rpc->connect_cb  = reconnect_cb;
 551
 552                 if (rpc_connect_sockaddr_async(rpc, &rpc->s) != 0) {
 553                         rpc_error_all_pdus(rpc, "RPC ERROR: Failed to reconnect async");
 554                         return -1;
 555                 }
 556         }
 557
 558         return 0;
 559 }
 560
 561
 562 int rpc_bind_udp(struct rpc_context *rpc, char *addr, int port)
 563 {
 564         struct addrinfo *ai = NULL;
 565         char service[6];
 566
 567         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 568
 569         if (rpc->is_udp == 0) {
 570                 rpc_set_error(rpc, "Cant not bind UDP. Not UDP context");
 571                 return -1;
 572         }
 573
 574         sprintf(service, "%d", port);
 575         if (getaddrinfo(addr, service, NULL, &ai) != 0) {
 576                 rpc_set_error(rpc, "Invalid address:%s. "
 577                         "Can not resolv into IPv4/v6 structure.");
 578                 return -1;
 579         }
 580
 581         switch(ai->ai_family) {
 582         case AF_INET:
 583                 rpc->fd = socket(ai->ai_family, SOCK_DGRAM, 0);
 584                 if (rpc->fd == -1) {
 585                         rpc_set_error(rpc, "Failed to create UDP socket: %s", strerror(errno));
 586                         freeaddrinfo(ai);
 587                         return -1;
 588                 }
 589
 590                 if (bind(rpc->fd, (struct sockaddr *)ai->ai_addr, sizeof(struct sockaddr_in)) != 0) {
 591                         rpc_set_error(rpc, "Failed to bind to UDP socket: %s",strerror(errno));
 592                         freeaddrinfo(ai);
 593                         return -1;
 594                 }
 595                 break;
 596         default:
 597                 rpc_set_error(rpc, "Can not handle UPD sockets of family %d yet", ai->ai_family);
 598                 freeaddrinfo(ai);
 599                 return -1;
 600         }
 601
 602         freeaddrinfo(ai);
 603
 604         return 0;
 605 }
 606
 607 int rpc_set_udp_destination(struct rpc_context *rpc, char *addr, int port, int is_broadcast)
 608 {
 609         struct addrinfo *ai = NULL;
 610         char service[6];
 611
 612         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 613
 614         if (rpc->is_udp == 0) {
 615                 rpc_set_error(rpc, "Can not set destination sockaddr. Not UDP context");
 616                 return -1;
 617         }
 618
 619         sprintf(service, "%d", port);
 620         if (getaddrinfo(addr, service, NULL, &ai) != 0) {
 621                 rpc_set_error(rpc, "Invalid address:%s. "
 622                         "Can not resolv into IPv4/v6 structure.");
 623                 return -1;
 624         }
 625
 626         if (rpc->udp_dest) {
 627                 free(rpc->udp_dest);
 628                 rpc->udp_dest = NULL;
 629         }
 630         rpc->udp_dest = malloc(ai->ai_addrlen);
 631         if (rpc->udp_dest == NULL) {
 632                 rpc_set_error(rpc, "Out of memory. Failed to allocate sockaddr structure");
 633                 freeaddrinfo(ai);
 634                 return -1;
 635         }
 636         memcpy(rpc->udp_dest, ai->ai_addr, ai->ai_addrlen);
 637         freeaddrinfo(ai);
 638
 639         rpc->is_broadcast = is_broadcast;
 640         setsockopt(rpc->fd, SOL_SOCKET, SO_BROADCAST, (char *)&is_broadcast, sizeof(is_broadcast));
 641
 642         return 0;
 643 }
 644
 645 struct sockaddr *rpc_get_recv_sockaddr(struct rpc_context *rpc)
 646 {
 647         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 648
 649         return (struct sockaddr *)&rpc->udp_src;
 650 }
 651
 652 int rpc_queue_length(struct rpc_context *rpc)
 653 {
 654         int i=0;
 655         struct rpc_pdu *pdu;
 656
 657         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 658
 659         for(pdu = rpc->outqueue; pdu; pdu = pdu->next) {
 660                 i++;
 661         }
 662         for(pdu = rpc->waitpdu; pdu; pdu = pdu->next) {
 663                 i++;
 664         }
 665         return i;
 666 }