lib/socket.c

   1 /*
   2    Copyright (C) 2010 by Ronnie Sahlberg <ronniesahlberg@gmail.com>
   3
   4    This program is free software; you can redistribute it and/or modify
   5    it under the terms of the GNU Lesser General Public License as published by
   6    the Free Software Foundation; either version 2.1 of the License, or
   7    (at your option) any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public License
  15    along with this program; if not, see <http://www.gnu.org/licenses/>.
  16 */
  17 #ifdef WIN32
  18 #include "win32_compat.h"
  19 #else
  20 #include <unistd.h>
  21 #include <arpa/inet.h>
  22 #include <sys/ioctl.h>
  23 #include <sys/socket.h>
  24 #include <netdb.h>
  25 #endif/*WIN32*/
  26
  27 #ifdef HAVE_CONFIG_H
  28 #include "config.h"
  29 #endif
  30
  31 #ifdef AROS
  32 #include "aros_compat.h"
  33 #endif
  34
  35 #ifdef HAVE_POLL_H
  36 #include <poll.h>
  37 #endif
  38
  39 #include <stdio.h>
  40 #include <stdlib.h>
  41 #include <assert.h>
  42 #include <fcntl.h>
  43 #include <string.h>
  44 #include <errno.h>
  45 #ifdef HAVE_SYS_FILIO_H
  46 #include <sys/filio.h>
  47 #endif
  48 #ifdef HAVE_SYS_SOCKIO_H
  49 #include <sys/sockio.h>
  50 #endif
  51 #include <sys/types.h>
  52 #include "libnfs-zdr.h"
  53 #include "libnfs.h"
  54 #include "libnfs-raw.h"
  55 #include "libnfs-private.h"
  56 #include "slist.h"
  57
  58 #ifdef WIN32
  59 //has to be included after stdlib!!
  60 #include "win32_errnowrapper.h"
  61 #endif
  62
  63
  64 static int rpc_reconnect_requeue(struct rpc_context *rpc);
  65 static int rpc_connect_sockaddr_async(struct rpc_context *rpc, struct sockaddr_storage *s);
  66
  67 static void set_nonblocking(int fd)
  68 {
  69         int v = 0;
  70 #if defined(WIN32)
  71         long nonblocking=1;
  72         v = ioctlsocket(fd, FIONBIO,&nonblocking);
  73 #else
  74         v = fcntl(fd, F_GETFL, 0);
  75         fcntl(fd, F_SETFL, v | O_NONBLOCK);
  76 #endif //FIXME
  77 }
  78
  79 int rpc_get_fd(struct rpc_context *rpc)
  80 {
  81         assert(rpc->magic == RPC_CONTEXT_MAGIC);
  82
  83         return rpc->fd;
  84 }
  85
  86 int rpc_which_events(struct rpc_context *rpc)
  87 {
  88         int events;
  89
  90         assert(rpc->magic == RPC_CONTEXT_MAGIC);
  91
  92         events = rpc->is_connected ? POLLIN : POLLOUT;
  93
  94         if (rpc->is_udp != 0) {
  95                 /* for udp sockets we only wait for pollin */
  96                 return POLLIN;
  97         }
  98
  99         if (rpc->outqueue) {
 100                 events |= POLLOUT;
 101         }
 102         return events;
 103 }
 104
 105 static int rpc_write_to_socket(struct rpc_context *rpc)
 106 {
 107         int32_t count;
 108
 109         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 110
 111         if (rpc->fd == -1) {
 112                 rpc_set_error(rpc, "trying to write but not connected");
 113                 return -1;
 114         }
 115
 116         while (rpc->outqueue != NULL) {
 117                 int64_t total;
 118
 119                 total = rpc->outqueue->outdata.size;
 120
 121                 count = send(rpc->fd, rpc->outqueue->outdata.data + rpc->outqueue->written, total - rpc->outqueue->written, 0);
 122                 if (count == -1) {
 123                         if (errno == EAGAIN || errno == EWOULDBLOCK) {
 124                                 return 0;
 125                         }
 126                         rpc_set_error(rpc, "Error when writing to socket :%s(%d)", strerror(errno), errno);
 127                         return -1;
 128                 }
 129
 130                 rpc->outqueue->written += count;
 131                 if (rpc->outqueue->written == total) {
 132                         struct rpc_pdu *pdu = rpc->outqueue;
 133
 134                         SLIST_REMOVE(&rpc->outqueue, pdu);
 135                         SLIST_ADD_END(&rpc->waitpdu, pdu);
 136                 }
 137         }
 138         return 0;
 139 }
 140
 141 static int rpc_read_from_socket(struct rpc_context *rpc)
 142 {
 143         int available;
 144         int size;
 145         int pdu_size;
 146         int32_t count;
 147
 148         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 149
 150         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 151
 152 #if defined(WIN32)
 153         if (ioctlsocket(rpc->fd, FIONREAD, &available) != 0) {
 154 #else
 155         if (ioctl(rpc->fd, FIONREAD, &available) != 0) {
 156 #endif
 157                 rpc_set_error(rpc, "Ioctl FIONREAD returned error : %d. Closing socket.", errno);
 158                 return -1;
 159         }
 160
 161         if (available == 0) {
 162                 rpc_set_error(rpc, "Socket has been closed");
 163                 return -1;
 164         }
 165
 166         if (rpc->is_udp) {
 167                 char *buf;
 168                 socklen_t socklen = sizeof(rpc->udp_src);
 169
 170                 buf = malloc(available);
 171                 if (buf == NULL) {
 172                         rpc_set_error(rpc, "Failed to malloc buffer for recvfrom");
 173                         return -1;
 174                 }
 175                 count = recvfrom(rpc->fd, buf, available, MSG_DONTWAIT, (struct sockaddr *)&rpc->udp_src, &socklen);
 176                 if (count < 0) {
 177                         rpc_set_error(rpc, "Failed recvfrom: %s", strerror(errno));
 178                         free(buf);
 179                 }
 180                 if (rpc_process_pdu(rpc, buf, count) != 0) {
 181                         rpc_set_error(rpc, "Invalid/garbage pdu received from server. Ignoring PDU");
 182                         free(buf);
 183                         return -1;
 184                 }
 185                 free(buf);
 186                 return 0;
 187         }
 188
 189         /* read record marker, 4 bytes at the beginning of every pdu */
 190         if (rpc->inbuf == NULL) {
 191                 rpc->insize = 4;
 192                 rpc->inbuf = malloc(rpc->insize);
 193                 if (rpc->inbuf == NULL) {
 194                         rpc_set_error(rpc, "Failed to allocate buffer for record marker, errno:%d. Closing socket.", errno);
 195                         return -1;
 196                 }
 197         }
 198         if (rpc->inpos < 4) {
 199                 size = 4 - rpc->inpos;
 200
 201                 count = recv(rpc->fd, rpc->inbuf + rpc->inpos, size, 0);
 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         count = recv(rpc->fd, rpc->inbuf + rpc->inpos, size, 0);
 238         if (count == -1) {
 239                 if (errno == EINTR) {
 240                         return 0;
 241                 }
 242                 rpc_set_error(rpc, "Read from socket failed, errno:%d. Closing socket.", errno);
 243                 return -1;
 244         }
 245         available  -= count;
 246         rpc->inpos += count;
 247
 248         if (rpc->inpos == rpc->insize) {
 249                 if (rpc_process_pdu(rpc, rpc->inbuf, pdu_size) != 0) {
 250                         rpc_set_error(rpc, "Invalid/garbage pdu received from server. Closing socket");
 251                         return -1;
 252                 }
 253                 free(rpc->inbuf);
 254                 rpc->inbuf  = NULL;
 255                 rpc->insize = 0;
 256                 rpc->inpos  = 0;
 257         }
 258
 259         return 0;
 260 }
 261
 262
 263
 264 int rpc_service(struct rpc_context *rpc, int revents)
 265 {
 266         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 267
 268         if (revents & POLLERR) {
 269 #ifdef WIN32
 270                 char err = 0;
 271 #else
 272                 int err = 0;
 273 #endif
 274                 socklen_t err_size = sizeof(err);
 275
 276                 if (getsockopt(rpc->fd, SOL_SOCKET, SO_ERROR,
 277                                 (char *)&err, &err_size) != 0 || err != 0) {
 278                         if (err == 0) {
 279                                 err = errno;
 280                         }
 281                         rpc_set_error(rpc, "rpc_service: socket error "
 282                                                "%s(%d).",
 283                                                strerror(err), err);
 284                 } else {
 285                         rpc_set_error(rpc, "rpc_service: POLLERR, "
 286                                                 "Unknown socket error.");
 287                 }
 288                 if (rpc->connect_cb != NULL) {
 289                         rpc->connect_cb(rpc, RPC_STATUS_ERROR, rpc->error_string, rpc->connect_data);
 290                 }
 291                 return -1;
 292         }
 293         if (revents & POLLHUP) {
 294                 rpc_set_error(rpc, "Socket failed with POLLHUP");
 295                 if (rpc->connect_cb != NULL) {
 296                         rpc->connect_cb(rpc, RPC_STATUS_ERROR, rpc->error_string, rpc->connect_data);
 297                 }
 298                 return -1;
 299         }
 300
 301         if (rpc->is_connected == 0 && rpc->fd != -1 && revents&POLLOUT) {
 302                 int err = 0;
 303                 socklen_t err_size = sizeof(err);
 304
 305                 if (getsockopt(rpc->fd, SOL_SOCKET, SO_ERROR,
 306                                 (char *)&err, &err_size) != 0 || err != 0) {
 307                         if (err == 0) {
 308                                 err = errno;
 309                         }
 310                         rpc_set_error(rpc, "rpc_service: socket error "
 311                                         "%s(%d) while connecting.",
 312                                         strerror(err), err);
 313                         if (rpc->connect_cb != NULL) {
 314                                 rpc->connect_cb(rpc, RPC_STATUS_ERROR,
 315                                         NULL, rpc->connect_data);
 316                         }
 317                         return -1;
 318                 }
 319
 320                 rpc->is_connected = 1;
 321                 if (rpc->connect_cb != NULL) {
 322                         rpc->connect_cb(rpc, RPC_STATUS_SUCCESS, NULL, rpc->connect_data);
 323                 }
 324                 return 0;
 325         }
 326
 327         if (revents & POLLIN) {
 328                 if (rpc_read_from_socket(rpc) != 0) {
 329                         rpc_reconnect_requeue(rpc);
 330                         return 0;
 331                 }
 332         }
 333
 334         if (revents & POLLOUT && rpc->outqueue != NULL) {
 335                 if (rpc_write_to_socket(rpc) != 0) {
 336                         rpc_set_error(rpc, "write to socket failed");
 337                         return -1;
 338                 }
 339         }
 340
 341         return 0;
 342 }
 343
 344 void rpc_set_autoreconnect(struct rpc_context *rpc)
 345 {
 346         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 347
 348         rpc->auto_reconnect = 1;
 349 }
 350
 351 void rpc_unset_autoreconnect(struct rpc_context *rpc)
 352 {
 353         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 354
 355         rpc->auto_reconnect = 0;
 356 }
 357
 358 static int rpc_connect_sockaddr_async(struct rpc_context *rpc, struct sockaddr_storage *s)
 359 {
 360         int socksize;
 361
 362         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 363
 364         switch (s->ss_family) {
 365         case AF_INET:
 366                 socksize = sizeof(struct sockaddr_in);
 367                 rpc->fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
 368                 break;
 369         default:
 370                 rpc_set_error(rpc, "Can not handle AF_FAMILY:%d", s->ss_family);
 371                 return -1;
 372         }
 373
 374         if (rpc->fd == -1) {
 375                 rpc_set_error(rpc, "Failed to open socket");
 376                 return -1;
 377         }
 378
 379         /* Some systems allow you to set capabilities on an executable
 380          * to allow the file to be executed with privilege to bind to
 381          * privileged system ports, even if the user is not root.
 382          *
 383          * Opportunistically try to bind the socket to a low numbered
 384          * system port in the hope that the user is either root or the
 385          * executable has the CAP_NET_BIND_SERVICE.
 386          *
 387          * As soon as we fail the bind() with EACCES we know we will never
 388          * be able to bind to a system port so we terminate the loop.
 389          *
 390          * On linux, use
 391          *    sudo setcap 'cap_net_bind_service=+ep' /path/executable
 392          * to make the executable able to bind to a system port.
 393          *
 394          * On Windows, there is no concept of privileged ports. Thus
 395          * binding will usually succeed.
 396          */
 397         {
 398                 struct sockaddr_in sin;
 399                 static int portOfs = 0;
 400                 const int firstPort = 512;      /* >= 512 according to Sun docs */
 401                 const int portCount = IPPORT_RESERVED - firstPort;
 402                 int startOfs = portOfs, port, rc;
 403
 404                 do {
 405                         rc = -1;
 406                         port = htons(firstPort + portOfs);
 407                         portOfs = (portOfs + 1) % portCount;
 408
 409                         /* skip well-known ports */
 410                         if (!getservbyport(port, "tcp")) {
 411                                 memset(&sin, 0, sizeof(sin));
 412                                 sin.sin_port        = port;
 413                                 sin.sin_family      = AF_INET;
 414                                 sin.sin_addr.s_addr = 0;
 415
 416                                 rc = bind(rpc->fd, (struct sockaddr *)&sin, sizeof(struct sockaddr_in));
 417 #if !defined(WIN32)
 418                                 /* we got EACCES, so don't try again */
 419                                 if (rc != 0 && errno == EACCES)
 420                                         break;
 421 #endif
 422                         }
 423                 } while (rc != 0 && portOfs != startOfs);
 424         }
 425
 426         set_nonblocking(rpc->fd);
 427
 428         if (connect(rpc->fd, (struct sockaddr *)s, socksize) != 0 && errno != EINPROGRESS) {
 429                 rpc_set_error(rpc, "connect() to server failed. %s(%d)", strerror(errno), errno);
 430                 return -1;
 431         }
 432
 433         return 0;
 434 }
 435
 436 int rpc_connect_async(struct rpc_context *rpc, const char *server, int port, rpc_cb cb, void *private_data)
 437 {
 438         struct sockaddr_in *sin = (struct sockaddr_in *)&rpc->s;
 439
 440         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 441
 442         if (rpc->fd != -1) {
 443                 rpc_set_error(rpc, "Trying to connect while already connected");
 444                 return -1;
 445         }
 446
 447         if (rpc->is_udp != 0) {
 448                 rpc_set_error(rpc, "Trying to connect on UDP socket");
 449                 return -1;
 450         }
 451
 452         rpc->auto_reconnect = 0;
 453
 454         sin->sin_family = AF_INET;
 455         sin->sin_port   = htons(port);
 456         if (inet_pton(AF_INET, server, &sin->sin_addr) != 1) {
 457                 rpc_set_error(rpc, "Not a valid server ip address");
 458                 return -1;
 459         }
 460
 461
 462         switch (rpc->s.ss_family) {
 463         case AF_INET:
 464 #ifdef HAVE_SOCKADDR_LEN
 465                 sin->sin_len = sizeof(struct sockaddr_in);
 466 #endif
 467                 break;
 468         }
 469
 470         rpc->connect_cb  = cb;
 471         rpc->connect_data = private_data;
 472
 473         if (rpc_connect_sockaddr_async(rpc, &rpc->s) != 0) {
 474                 return -1;
 475         }
 476
 477         return 0;
 478 }
 479
 480 int rpc_disconnect(struct rpc_context *rpc, char *error)
 481 {
 482         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 483
 484         rpc_unset_autoreconnect(rpc);
 485
 486         if (rpc->fd != -1) {
 487 #if defined(WIN32)
 488                 closesocket(rpc->fd);
 489 #else
 490                 close(rpc->fd);
 491 #endif
 492         }
 493         rpc->fd  = -1;
 494
 495         rpc->is_connected = 0;
 496
 497         rpc_error_all_pdus(rpc, error);
 498
 499         return 0;
 500 }
 501
 502 static void reconnect_cb(struct rpc_context *rpc, int status, void *data _U_, void *private_data)
 503 {
 504         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 505
 506         if (status != RPC_STATUS_SUCCESS) {
 507                 rpc_error_all_pdus(rpc, "RPC ERROR: Failed to reconnect async");
 508                 return;
 509         }
 510
 511         rpc->is_connected = 1;
 512         rpc->connect_cb   = NULL;
 513 }
 514
 515 /* disconnect but do not error all PDUs, just move pdus in-flight back to the outqueue and reconnect */
 516 static int rpc_reconnect_requeue(struct rpc_context *rpc)
 517 {
 518         struct rpc_pdu *pdu;
 519
 520         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 521
 522         if (rpc->fd != -1) {
 523 #if defined(WIN32)
 524                 closesocket(rpc->fd);
 525 #else
 526                 close(rpc->fd);
 527 #endif
 528         }
 529         rpc->fd  = -1;
 530
 531         rpc->is_connected = 0;
 532
 533         /* socket is closed so we will not get any replies to any commands
 534          * in flight. Move them all over from the waitpdu queue back to the out queue
 535          */
 536         for (pdu=rpc->waitpdu; pdu; pdu=pdu->next) {
 537                 SLIST_REMOVE(&rpc->waitpdu, pdu);
 538                 SLIST_ADD(&rpc->outqueue, pdu);
 539                 /* we have to re-send the whole pdu again */
 540                 pdu->written = 0;
 541         }
 542
 543         if (rpc->auto_reconnect != 0) {
 544                 rpc->connect_cb  = reconnect_cb;
 545
 546                 if (rpc_connect_sockaddr_async(rpc, &rpc->s) != 0) {
 547                         rpc_error_all_pdus(rpc, "RPC ERROR: Failed to reconnect async");
 548                         return -1;
 549                 }
 550         }
 551
 552         return 0;
 553 }
 554
 555
 556 int rpc_bind_udp(struct rpc_context *rpc, char *addr, int port)
 557 {
 558         struct addrinfo *ai = NULL;
 559         char service[6];
 560
 561         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 562
 563         if (rpc->is_udp == 0) {
 564                 rpc_set_error(rpc, "Cant not bind UDP. Not UDP context");
 565                 return -1;
 566         }
 567
 568         sprintf(service, "%d", port);
 569         if (getaddrinfo(addr, service, NULL, &ai) != 0) {
 570                 rpc_set_error(rpc, "Invalid address:%s. "
 571                         "Can not resolv into IPv4/v6 structure.");
 572                 return -1;
 573         }
 574
 575         switch(ai->ai_family) {
 576         case AF_INET:
 577                 rpc->fd = socket(ai->ai_family, SOCK_DGRAM, 0);
 578                 if (rpc->fd == -1) {
 579                         rpc_set_error(rpc, "Failed to create UDP socket: %s", strerror(errno));
 580                         freeaddrinfo(ai);
 581                         return -1;
 582                 }
 583
 584                 if (bind(rpc->fd, (struct sockaddr *)ai->ai_addr, sizeof(struct sockaddr_in)) != 0) {
 585                         rpc_set_error(rpc, "Failed to bind to UDP socket: %s",strerror(errno));
 586                         freeaddrinfo(ai);
 587                         return -1;
 588                 }
 589                 break;
 590         default:
 591                 rpc_set_error(rpc, "Can not handle UPD sockets of family %d yet", ai->ai_family);
 592                 freeaddrinfo(ai);
 593                 return -1;
 594         }
 595
 596         freeaddrinfo(ai);
 597
 598         return 0;
 599 }
 600
 601 int rpc_set_udp_destination(struct rpc_context *rpc, char *addr, int port, int is_broadcast)
 602 {
 603         struct addrinfo *ai = NULL;
 604         char service[6];
 605
 606         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 607
 608         if (rpc->is_udp == 0) {
 609                 rpc_set_error(rpc, "Can not set destination sockaddr. Not UDP context");
 610                 return -1;
 611         }
 612
 613         sprintf(service, "%d", port);
 614         if (getaddrinfo(addr, service, NULL, &ai) != 0) {
 615                 rpc_set_error(rpc, "Invalid address:%s. "
 616                         "Can not resolv into IPv4/v6 structure.");
 617                 return -1;
 618         }
 619
 620         if (rpc->udp_dest) {
 621                 free(rpc->udp_dest);
 622                 rpc->udp_dest = NULL;
 623         }
 624         rpc->udp_dest = malloc(ai->ai_addrlen);
 625         if (rpc->udp_dest == NULL) {
 626                 rpc_set_error(rpc, "Out of memory. Failed to allocate sockaddr structure");
 627                 freeaddrinfo(ai);
 628                 return -1;
 629         }
 630         memcpy(rpc->udp_dest, ai->ai_addr, ai->ai_addrlen);
 631         freeaddrinfo(ai);
 632
 633         rpc->is_broadcast = is_broadcast;
 634         setsockopt(rpc->fd, SOL_SOCKET, SO_BROADCAST, (char *)&is_broadcast, sizeof(is_broadcast));
 635
 636         return 0;
 637 }
 638
 639 struct sockaddr *rpc_get_recv_sockaddr(struct rpc_context *rpc)
 640 {
 641         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 642
 643         return (struct sockaddr *)&rpc->udp_src;
 644 }
 645
 646 int rpc_queue_length(struct rpc_context *rpc)
 647 {
 648         int i=0;
 649         struct rpc_pdu *pdu;
 650
 651         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 652
 653         for(pdu = rpc->outqueue; pdu; pdu = pdu->next) {
 654                 i++;
 655         }
 656         for(pdu = rpc->waitpdu; pdu; pdu = pdu->next) {
 657                 i++;
 658         }
 659         return i;
 660 }