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 <poll.h>
  22 #include <arpa/inet.h>
  23 #include <sys/ioctl.h>
  24 #include <sys/socket.h>
  25 #include <netdb.h>
  26 #endif/*WIN32*/
  27
  28 #ifdef HAVE_CONFIG_H
  29 #include "config.h"
  30 #endif
  31 #include <stdio.h>
  32 #include <stdlib.h>
  33 #include <assert.h>
  34 #include <fcntl.h>
  35 #include <string.h>
  36 #include <errno.h>
  37 #ifdef HAVE_SYS_FILIO_H
  38 #include <sys/filio.h>
  39 #endif
  40 #ifdef HAVE_SYS_SOCKIO_H
  41 #include <sys/sockio.h>
  42 #endif
  43 #include <sys/types.h>
  44 #include "libnfs-zdr.h"
  45 #include "libnfs.h"
  46 #include "libnfs-raw.h"
  47 #include "libnfs-private.h"
  48 #include "slist.h"
  49
  50 #ifdef WIN32
  51 //has to be included after stdlib!!
  52 #include "win32_errnowrapper.h"
  53 #endif
  54
  55
  56 static int rpc_reconnect_requeue(struct rpc_context *rpc);
  57 static int rpc_connect_sockaddr_async(struct rpc_context *rpc, struct sockaddr_storage *s);
  58
  59 static void set_nonblocking(int fd)
  60 {
  61         int v = 0;
  62 #if defined(WIN32)
  63         long nonblocking=1;
  64         v = ioctlsocket(fd, FIONBIO,&nonblocking);
  65 #else
  66         v = fcntl(fd, F_GETFL, 0);
  67         fcntl(fd, F_SETFL, v | O_NONBLOCK);
  68 #endif //FIXME
  69 }
  70
  71 int rpc_get_fd(struct rpc_context *rpc)
  72 {
  73         assert(rpc->magic == RPC_CONTEXT_MAGIC);
  74
  75         return rpc->fd;
  76 }
  77
  78 int rpc_which_events(struct rpc_context *rpc)
  79 {
  80         int events;
  81
  82         assert(rpc->magic == RPC_CONTEXT_MAGIC);
  83
  84         events = rpc->is_connected ? POLLIN : POLLOUT;
  85
  86         if (rpc->is_udp != 0) {
  87                 /* for udp sockets we only wait for pollin */
  88                 return POLLIN;
  89         }
  90
  91         if (rpc->outqueue) {
  92                 events |= POLLOUT;
  93         }
  94         return events;
  95 }
  96
  97 static int rpc_write_to_socket(struct rpc_context *rpc)
  98 {
  99         int32_t count;
 100
 101         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 102
 103         if (rpc->fd == -1) {
 104                 rpc_set_error(rpc, "trying to write but not connected");
 105                 return -1;
 106         }
 107
 108         while (rpc->outqueue != NULL) {
 109                 int64_t total;
 110
 111                 total = rpc->outqueue->outdata.size;
 112
 113 #if defined(WIN32)
 114                 count = send(rpc->fd, rpc->outqueue->outdata.data + rpc->outqueue->written, total - rpc->outqueue->written, 0);
 115 #else
 116                 count = write(rpc->fd, rpc->outqueue->outdata.data + rpc->outqueue->written, total - rpc->outqueue->written);
 117 #endif
 118                 if (count == -1) {
 119                         if (errno == EAGAIN || errno == EWOULDBLOCK) {
 120                                 return 0;
 121                         }
 122                         rpc_set_error(rpc, "Error when writing to socket :%s(%d)", strerror(errno), errno);
 123                         return -1;
 124                 }
 125
 126                 rpc->outqueue->written += count;
 127                 if (rpc->outqueue->written == total) {
 128                         struct rpc_pdu *pdu = rpc->outqueue;
 129
 130                         SLIST_REMOVE(&rpc->outqueue, pdu);
 131                         SLIST_ADD_END(&rpc->waitpdu, pdu);
 132                 }
 133         }
 134         return 0;
 135 }
 136
 137 static int rpc_read_from_socket(struct rpc_context *rpc)
 138 {
 139         int available;
 140         int size;
 141         int pdu_size;
 142         int32_t count;
 143
 144         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 145
 146         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 147
 148 #if defined(WIN32)
 149         if (ioctlsocket(rpc->fd, FIONREAD, &available) != 0) {
 150 #else
 151         if (ioctl(rpc->fd, FIONREAD, &available) != 0) {
 152 #endif
 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 #if defined(WIN32)
 198                 count = recv(rpc->fd, rpc->inbuf + rpc->inpos, size, 0);
 199 #else
 200                 count = read(rpc->fd, rpc->inbuf + rpc->inpos, size);
 201 #endif
 202                 if (count == -1) {
 203                         if (errno == EINTR) {
 204                                 return 0;
 205                         }
 206                         rpc_set_error(rpc, "Read from socket failed, errno:%d. Closing socket.", errno);
 207                         return -1;
 208                 }
 209                 available  -= count;
 210                 rpc->inpos += count;
 211         }
 212
 213         if (available == 0) {
 214                 return 0;
 215         }
 216
 217         pdu_size = rpc_get_pdu_size(rpc->inbuf);
 218         if (rpc->insize < pdu_size) {
 219                 unsigned char *buf;
 220
 221                 buf = malloc(pdu_size);
 222                 if (buf == NULL) {
 223                         rpc_set_error(rpc, "Failed to allocate buffer of %d bytes for pdu, errno:%d. Closing socket.", pdu_size, errno);
 224                         return -1;
 225                 }
 226                 memcpy(buf, rpc->inbuf, rpc->insize);
 227                 free(rpc->inbuf);
 228                 rpc->inbuf  = buf;
 229                 rpc->insize = rpc_get_pdu_size(rpc->inbuf);
 230         }
 231
 232         size = available;
 233         if (size > rpc->insize - rpc->inpos) {
 234                 size = rpc->insize - rpc->inpos;
 235         }
 236
 237 #if defined(WIN32)
 238         count = recv(rpc->fd, rpc->inbuf + rpc->inpos, size, 0);
 239 #else
 240         count = read(rpc->fd, rpc->inbuf + rpc->inpos, size);
 241 #endif
 242         if (count == -1) {
 243                 if (errno == EINTR) {
 244                         return 0;
 245                 }
 246                 rpc_set_error(rpc, "Read from socket failed, errno:%d. Closing socket.", errno);
 247                 return -1;
 248         }
 249         available  -= count;
 250         rpc->inpos += count;
 251
 252         if (rpc->inpos == rpc->insize) {
 253                 if (rpc_process_pdu(rpc, rpc->inbuf, pdu_size) != 0) {
 254                         rpc_set_error(rpc, "Invalid/garbage pdu received from server. Closing socket");
 255                         return -1;
 256                 }
 257                 free(rpc->inbuf);
 258                 rpc->inbuf  = NULL;
 259                 rpc->insize = 0;
 260                 rpc->inpos  = 0;
 261         }
 262
 263         return 0;
 264 }
 265
 266
 267
 268 int rpc_service(struct rpc_context *rpc, int revents)
 269 {
 270         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 271
 272         if (revents & POLLERR) {
 273 #ifdef WIN32
 274                 char err = 0;
 275 #else
 276                 int err = 0;
 277 #endif
 278                 socklen_t err_size = sizeof(err);
 279
 280                 if (getsockopt(rpc->fd, SOL_SOCKET, SO_ERROR,
 281                                 (char *)&err, &err_size) != 0 || err != 0) {
 282                         if (err == 0) {
 283                                 err = errno;
 284                         }
 285                         rpc_set_error(rpc, "rpc_service: socket error "
 286                                                "%s(%d).",
 287                                                strerror(err), err);
 288                 } else {
 289                         rpc_set_error(rpc, "rpc_service: POLLERR, "
 290                                                 "Unknown socket error.");
 291                 }
 292                 if (rpc->connect_cb != NULL) {
 293                         rpc->connect_cb(rpc, RPC_STATUS_ERROR, rpc->error_string, rpc->connect_data);
 294                 }
 295                 return -1;
 296         }
 297         if (revents & POLLHUP) {
 298                 rpc_set_error(rpc, "Socket failed with POLLHUP");
 299                 if (rpc->connect_cb != NULL) {
 300                         rpc->connect_cb(rpc, RPC_STATUS_ERROR, rpc->error_string, rpc->connect_data);
 301                 }
 302                 return -1;
 303         }
 304
 305         if (rpc->is_connected == 0 && rpc->fd != -1 && revents&POLLOUT) {
 306                 int err = 0;
 307                 socklen_t err_size = sizeof(err);
 308
 309                 if (getsockopt(rpc->fd, SOL_SOCKET, SO_ERROR,
 310                                 (char *)&err, &err_size) != 0 || err != 0) {
 311                         if (err == 0) {
 312                                 err = errno;
 313                         }
 314                         rpc_set_error(rpc, "rpc_service: socket error "
 315                                         "%s(%d) while connecting.",
 316                                         strerror(err), err);
 317                         if (rpc->connect_cb != NULL) {
 318                                 rpc->connect_cb(rpc, RPC_STATUS_ERROR,
 319                                         NULL, rpc->connect_data);
 320                         }
 321                         return -1;
 322                 }
 323
 324                 rpc->is_connected = 1;
 325                 if (rpc->connect_cb != NULL) {
 326                         rpc->connect_cb(rpc, RPC_STATUS_SUCCESS, NULL, rpc->connect_data);
 327                 }
 328                 return 0;
 329         }
 330
 331         if (revents & POLLIN) {
 332                 if (rpc_read_from_socket(rpc) != 0) {
 333                         rpc_reconnect_requeue(rpc);
 334                         return 0;
 335                 }
 336         }
 337
 338         if (revents & POLLOUT && rpc->outqueue != NULL) {
 339                 if (rpc_write_to_socket(rpc) != 0) {
 340                         rpc_set_error(rpc, "write to socket failed");
 341                         return -1;
 342                 }
 343         }
 344
 345         return 0;
 346 }
 347
 348 void rpc_set_autoreconnect(struct rpc_context *rpc)
 349 {
 350         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 351
 352         rpc->auto_reconnect = 1;
 353 }
 354
 355 void rpc_unset_autoreconnect(struct rpc_context *rpc)
 356 {
 357         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 358
 359         rpc->auto_reconnect = 0;
 360 }
 361
 362 static int rpc_connect_sockaddr_async(struct rpc_context *rpc, struct sockaddr_storage *s)
 363 {
 364         int socksize;
 365
 366         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 367
 368         switch (s->ss_family) {
 369         case AF_INET:
 370                 socksize = sizeof(struct sockaddr_in);
 371                 rpc->fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
 372                 break;
 373         default:
 374                 rpc_set_error(rpc, "Can not handle AF_FAMILY:%d", s->ss_family);
 375                 return -1;
 376         }
 377
 378         if (rpc->fd == -1) {
 379                 rpc_set_error(rpc, "Failed to open socket");
 380                 return -1;
 381         }
 382
 383         /* Some systems allow you to set capabilities on an executable
 384          * to allow the file to be executed with privilege to bind to
 385          * privileged system ports, even if the user is not root.
 386          *
 387          * Opportunistically try to bind the socket to a low numbered
 388          * system port in the hope that the user is either root or the
 389          * executable has the CAP_NET_BIND_SERVICE.
 390          *
 391          * As soon as we fail the bind() with EACCES we know we will never
 392          * be able to bind to a system port so we terminate the loop.
 393          *
 394          * On linux, use
 395          *    sudo setcap 'cap_net_bind_service=+ep' /path/executable
 396          * to make the executable able to bind to a system port.
 397          *
 398          * On Windows, there is no concept of privileged ports. Thus
 399          * binding will usually succeed.
 400          */
 401         {
 402                 struct sockaddr_in sin;
 403                 static int portOfs = 0;
 404                 const int firstPort = 512;      /* >= 512 according to Sun docs */
 405                 const int portCount = IPPORT_RESERVED - firstPort;
 406                 int startOfs = portOfs, port, rc;
 407
 408                 do {
 409                         rc = -1;
 410                         port = htons(firstPort + portOfs);
 411                         portOfs = (portOfs + 1) % portCount;
 412
 413                         /* skip well-known ports */
 414                         if (!getservbyport(port, "tcp")) {
 415                                 memset(&sin, 0, sizeof(sin));
 416                                 sin.sin_port        = port;
 417                                 sin.sin_family      = AF_INET;
 418                                 sin.sin_addr.s_addr = 0;
 419
 420                                 rc = bind(rpc->fd, (struct sockaddr *)&sin, sizeof(struct sockaddr_in));
 421 #if !defined(WIN32)
 422                                 /* we got EACCES, so don't try again */
 423                                 if (rc != 0 && errno == EACCES)
 424                                         break;
 425 #endif
 426                         }
 427                 } while (rc != 0 && portOfs != startOfs);
 428         }
 429
 430         set_nonblocking(rpc->fd);
 431
 432         if (connect(rpc->fd, (struct sockaddr *)s, socksize) != 0 && errno != EINPROGRESS) {
 433                 rpc_set_error(rpc, "connect() to server failed. %s(%d)", strerror(errno), errno);
 434                 return -1;
 435         }
 436
 437         return 0;
 438 }
 439
 440 int rpc_connect_async(struct rpc_context *rpc, const char *server, int port, rpc_cb cb, void *private_data)
 441 {
 442         struct sockaddr_in *sin = (struct sockaddr_in *)&rpc->s;
 443
 444         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 445
 446         if (rpc->fd != -1) {
 447                 rpc_set_error(rpc, "Trying to connect while already connected");
 448                 return -1;
 449         }
 450
 451         if (rpc->is_udp != 0) {
 452                 rpc_set_error(rpc, "Trying to connect on UDP socket");
 453                 return -1;
 454         }
 455
 456         rpc->auto_reconnect = 0;
 457
 458         sin->sin_family = AF_INET;
 459         sin->sin_port   = htons(port);
 460         if (inet_pton(AF_INET, server, &sin->sin_addr) != 1) {
 461                 rpc_set_error(rpc, "Not a valid server ip address");
 462                 return -1;
 463         }
 464
 465
 466         switch (rpc->s.ss_family) {
 467         case AF_INET:
 468 #ifdef HAVE_SOCKADDR_LEN
 469                 sin->sin_len = sizeof(struct sockaddr_in);
 470 #endif
 471                 break;
 472         }
 473
 474         rpc->connect_cb  = cb;
 475         rpc->connect_data = private_data;
 476
 477         if (rpc_connect_sockaddr_async(rpc, &rpc->s) != 0) {
 478                 return -1;
 479         }
 480
 481         return 0;
 482 }
 483
 484 int rpc_disconnect(struct rpc_context *rpc, char *error)
 485 {
 486         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 487
 488         rpc_unset_autoreconnect(rpc);
 489
 490         if (rpc->fd != -1) {
 491 #if defined(WIN32)
 492                 closesocket(rpc->fd);
 493 #else
 494                 close(rpc->fd);
 495 #endif
 496         }
 497         rpc->fd  = -1;
 498
 499         rpc->is_connected = 0;
 500
 501         rpc_error_all_pdus(rpc, error);
 502
 503         return 0;
 504 }
 505
 506 static void reconnect_cb(struct rpc_context *rpc, int status, void *data _U_, void *private_data)
 507 {
 508         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 509
 510         if (status != RPC_STATUS_SUCCESS) {
 511                 rpc_error_all_pdus(rpc, "RPC ERROR: Failed to reconnect async");
 512                 return;
 513         }
 514
 515         rpc->is_connected = 1;
 516         rpc->connect_cb   = NULL;
 517 }
 518
 519 /* disconnect but do not error all PDUs, just move pdus in-flight back to the outqueue and reconnect */
 520 static int rpc_reconnect_requeue(struct rpc_context *rpc)
 521 {
 522         struct rpc_pdu *pdu;
 523
 524         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 525
 526         if (rpc->fd != -1) {
 527 #if defined(WIN32)
 528                 closesocket(rpc->fd);
 529 #else
 530                 close(rpc->fd);
 531 #endif
 532         }
 533         rpc->fd  = -1;
 534
 535         rpc->is_connected = 0;
 536
 537         /* socket is closed so we will not get any replies to any commands
 538          * in flight. Move them all over from the waitpdu queue back to the out queue
 539          */
 540         for (pdu=rpc->waitpdu; pdu; pdu=pdu->next) {
 541                 SLIST_REMOVE(&rpc->waitpdu, pdu);
 542                 SLIST_ADD(&rpc->outqueue, pdu);
 543                 /* we have to re-send the whole pdu again */
 544                 pdu->written = 0;
 545         }
 546
 547         if (rpc->auto_reconnect != 0) {
 548                 rpc->connect_cb  = reconnect_cb;
 549
 550                 if (rpc_connect_sockaddr_async(rpc, &rpc->s) != 0) {
 551                         rpc_error_all_pdus(rpc, "RPC ERROR: Failed to reconnect async");
 552                         return -1;
 553                 }
 554         }
 555
 556         return 0;
 557 }
 558
 559
 560 int rpc_bind_udp(struct rpc_context *rpc, char *addr, int port)
 561 {
 562         struct addrinfo *ai = NULL;
 563         char service[6];
 564
 565         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 566
 567         if (rpc->is_udp == 0) {
 568                 rpc_set_error(rpc, "Cant not bind UDP. Not UDP context");
 569                 return -1;
 570         }
 571
 572         sprintf(service, "%d", port);
 573         if (getaddrinfo(addr, service, NULL, &ai) != 0) {
 574                 rpc_set_error(rpc, "Invalid address:%s. "
 575                         "Can not resolv into IPv4/v6 structure.");
 576                 return -1;
 577         }
 578
 579         switch(ai->ai_family) {
 580         case AF_INET:
 581                 rpc->fd = socket(ai->ai_family, SOCK_DGRAM, 0);
 582                 if (rpc->fd == -1) {
 583                         rpc_set_error(rpc, "Failed to create UDP socket: %s", strerror(errno));
 584                         freeaddrinfo(ai);
 585                         return -1;
 586                 }
 587
 588                 if (bind(rpc->fd, (struct sockaddr *)ai->ai_addr, sizeof(struct sockaddr_in)) != 0) {
 589                         rpc_set_error(rpc, "Failed to bind to UDP socket: %s",strerror(errno));
 590                         freeaddrinfo(ai);
 591                         return -1;
 592                 }
 593                 break;
 594         default:
 595                 rpc_set_error(rpc, "Can not handle UPD sockets of family %d yet", ai->ai_family);
 596                 freeaddrinfo(ai);
 597                 return -1;
 598         }
 599
 600         freeaddrinfo(ai);
 601
 602         return 0;
 603 }
 604
 605 int rpc_set_udp_destination(struct rpc_context *rpc, char *addr, int port, int is_broadcast)
 606 {
 607         struct addrinfo *ai = NULL;
 608         char service[6];
 609
 610         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 611
 612         if (rpc->is_udp == 0) {
 613                 rpc_set_error(rpc, "Can not set destination sockaddr. Not UDP context");
 614                 return -1;
 615         }
 616
 617         sprintf(service, "%d", port);
 618         if (getaddrinfo(addr, service, NULL, &ai) != 0) {
 619                 rpc_set_error(rpc, "Invalid address:%s. "
 620                         "Can not resolv into IPv4/v6 structure.");
 621                 return -1;
 622         }
 623
 624         if (rpc->udp_dest) {
 625                 free(rpc->udp_dest);
 626                 rpc->udp_dest = NULL;
 627         }
 628         rpc->udp_dest = malloc(ai->ai_addrlen);
 629         if (rpc->udp_dest == NULL) {
 630                 rpc_set_error(rpc, "Out of memory. Failed to allocate sockaddr structure");
 631                 freeaddrinfo(ai);
 632                 return -1;
 633         }
 634         memcpy(rpc->udp_dest, ai->ai_addr, ai->ai_addrlen);
 635         freeaddrinfo(ai);
 636
 637         rpc->is_broadcast = is_broadcast;
 638         setsockopt(rpc->fd, SOL_SOCKET, SO_BROADCAST, (char *)&is_broadcast, sizeof(is_broadcast));
 639
 640         return 0;
 641 }
 642
 643 struct sockaddr *rpc_get_recv_sockaddr(struct rpc_context *rpc)
 644 {
 645         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 646
 647         return (struct sockaddr *)&rpc->udp_src;
 648 }
 649
 650 int rpc_queue_length(struct rpc_context *rpc)
 651 {
 652         int i=0;
 653         struct rpc_pdu *pdu;
 654
 655         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 656
 657         for(pdu = rpc->outqueue; pdu; pdu = pdu->next) {
 658                 i++;
 659         }
 660         for(pdu = rpc->waitpdu; pdu; pdu = pdu->next) {
 661                 i++;
 662         }
 663         return i;
 664 }