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 #include <sys/socket.h>
  30 #include <netdb.h>
  31 #endif/*WIN32*/
  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 #include <stdio.h>
  46 #include <stdlib.h>
  47 #include <assert.h>
  48 #include <fcntl.h>
  49 #include <string.h>
  50 #include <errno.h>
  51 #ifdef HAVE_SYS_FILIO_H
  52 #include <sys/filio.h>
  53 #endif
  54 #ifdef HAVE_SYS_SOCKIO_H
  55 #include <sys/sockio.h>
  56 #endif
  57 #include <sys/types.h>
  58 #include "libnfs-zdr.h"
  59 #include "libnfs.h"
  60 #include "libnfs-raw.h"
  61 #include "libnfs-private.h"
  62 #include "slist.h"
  63
  64 #ifdef WIN32
  65 //has to be included after stdlib!!
  66 #include "win32_errnowrapper.h"
  67 #endif
  68
  69
  70 static int rpc_reconnect_requeue(struct rpc_context *rpc);
  71 static int rpc_connect_sockaddr_async(struct rpc_context *rpc, struct sockaddr_storage *s);
  72
  73 static void set_nonblocking(int fd)
  74 {
  75         int v = 0;
  76 #if defined(WIN32)
  77         long nonblocking=1;
  78         v = ioctl(fd, FIONBIO, &nonblocking);
  79 #else
  80         v = fcntl(fd, F_GETFL, 0);
  81         fcntl(fd, F_SETFL, v | O_NONBLOCK);
  82 #endif //FIXME
  83 }
  84
  85 int rpc_get_fd(struct rpc_context *rpc)
  86 {
  87         assert(rpc->magic == RPC_CONTEXT_MAGIC);
  88
  89         return rpc->fd;
  90 }
  91
  92 int rpc_which_events(struct rpc_context *rpc)
  93 {
  94         int events;
  95
  96         assert(rpc->magic == RPC_CONTEXT_MAGIC);
  97
  98         events = rpc->is_connected ? POLLIN : POLLOUT;
  99
 100         if (rpc->is_udp != 0) {
 101                 /* for udp sockets we only wait for pollin */
 102                 return POLLIN;
 103         }
 104
 105         if (rpc->outqueue) {
 106                 events |= POLLOUT;
 107         }
 108         return events;
 109 }
 110
 111 static int rpc_write_to_socket(struct rpc_context *rpc)
 112 {
 113         int32_t count;
 114
 115         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 116
 117         if (rpc->fd == -1) {
 118                 rpc_set_error(rpc, "trying to write but not connected");
 119                 return -1;
 120         }
 121
 122         while (rpc->outqueue != NULL) {
 123                 int64_t total;
 124
 125                 total = rpc->outqueue->outdata.size;
 126
 127                 count = send(rpc->fd, rpc->outqueue->outdata.data + rpc->outqueue->written, total - rpc->outqueue->written, 0);
 128                 if (count == -1) {
 129                         if (errno == EAGAIN || errno == EWOULDBLOCK) {
 130                                 return 0;
 131                         }
 132                         rpc_set_error(rpc, "Error when writing to socket :%s(%d)", strerror(errno), errno);
 133                         return -1;
 134                 }
 135
 136                 rpc->outqueue->written += count;
 137                 if (rpc->outqueue->written == total) {
 138                         struct rpc_pdu *pdu = rpc->outqueue;
 139
 140                         SLIST_REMOVE(&rpc->outqueue, pdu);
 141                         SLIST_ADD_END(&rpc->waitpdu, pdu);
 142                 }
 143         }
 144         return 0;
 145 }
 146
 147 static int rpc_read_from_socket(struct rpc_context *rpc)
 148 {
 149         int available;
 150         int size;
 151         int pdu_size;
 152         int32_t count;
 153
 154         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 155
 156         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 157
 158         if (ioctl(rpc->fd, FIONREAD, &available) != 0) {
 159                 rpc_set_error(rpc, "Ioctl FIONREAD returned error : %d. Closing socket.", errno);
 160                 return -1;
 161         }
 162
 163         if (available == 0) {
 164                 rpc_set_error(rpc, "Socket has been closed");
 165                 return -1;
 166         }
 167
 168         if (rpc->is_udp) {
 169                 char *buf;
 170                 socklen_t socklen = sizeof(rpc->udp_src);
 171
 172                 buf = malloc(available);
 173                 if (buf == NULL) {
 174                         rpc_set_error(rpc, "Failed to malloc buffer for recvfrom");
 175                         return -1;
 176                 }
 177                 count = recvfrom(rpc->fd, buf, available, MSG_DONTWAIT, (struct sockaddr *)&rpc->udp_src, &socklen);
 178                 if (count < 0) {
 179                         rpc_set_error(rpc, "Failed recvfrom: %s", strerror(errno));
 180                         free(buf);
 181                 }
 182                 if (rpc_process_pdu(rpc, buf, count) != 0) {
 183                         rpc_set_error(rpc, "Invalid/garbage pdu received from server. Ignoring PDU");
 184                         free(buf);
 185                         return -1;
 186                 }
 187                 free(buf);
 188                 return 0;
 189         }
 190
 191         /* read record marker, 4 bytes at the beginning of every pdu */
 192         if (rpc->inbuf == NULL) {
 193                 rpc->insize = 4;
 194                 rpc->inbuf = malloc(rpc->insize);
 195                 if (rpc->inbuf == NULL) {
 196                         rpc_set_error(rpc, "Failed to allocate buffer for record marker, errno:%d. Closing socket.", errno);
 197                         return -1;
 198                 }
 199         }
 200         if (rpc->inpos < 4) {
 201                 size = 4 - rpc->inpos;
 202
 203                 count = recv(rpc->fd, rpc->inbuf + rpc->inpos, size, 0);
 204                 if (count == -1) {
 205                         if (errno == EINTR) {
 206                                 return 0;
 207                         }
 208                         rpc_set_error(rpc, "Read from socket failed, errno:%d. Closing socket.", errno);
 209                         return -1;
 210                 }
 211                 available  -= count;
 212                 rpc->inpos += count;
 213         }
 214
 215         if (available == 0) {
 216                 return 0;
 217         }
 218
 219         pdu_size = rpc_get_pdu_size(rpc->inbuf);
 220         if (rpc->insize < pdu_size) {
 221                 unsigned char *buf;
 222
 223                 buf = malloc(pdu_size);
 224                 if (buf == NULL) {
 225                         rpc_set_error(rpc, "Failed to allocate buffer of %d bytes for pdu, errno:%d. Closing socket.", pdu_size, errno);
 226                         return -1;
 227                 }
 228                 memcpy(buf, rpc->inbuf, rpc->insize);
 229                 free(rpc->inbuf);
 230                 rpc->inbuf  = buf;
 231                 rpc->insize = rpc_get_pdu_size(rpc->inbuf);
 232         }
 233
 234         size = available;
 235         if (size > rpc->insize - rpc->inpos) {
 236                 size = rpc->insize - rpc->inpos;
 237         }
 238
 239         count = recv(rpc->fd, rpc->inbuf + rpc->inpos, size, 0);
 240         if (count == -1) {
 241                 if (errno == EINTR) {
 242                         return 0;
 243                 }
 244                 rpc_set_error(rpc, "Read from socket failed, errno:%d. Closing socket.", errno);
 245                 return -1;
 246         }
 247         available  -= count;
 248         rpc->inpos += count;
 249
 250         if (rpc->inpos == rpc->insize) {
 251                 if (rpc_process_pdu(rpc, rpc->inbuf, pdu_size) != 0) {
 252                         rpc_set_error(rpc, "Invalid/garbage pdu received from server. Closing socket");
 253                         return -1;
 254                 }
 255                 free(rpc->inbuf);
 256                 rpc->inbuf  = NULL;
 257                 rpc->insize = 0;
 258                 rpc->inpos  = 0;
 259         }
 260
 261         return 0;
 262 }
 263
 264
 265
 266 int rpc_service(struct rpc_context *rpc, int revents)
 267 {
 268         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 269
 270         if (revents & POLLERR) {
 271 #ifdef WIN32
 272                 char err = 0;
 273 #else
 274                 int err = 0;
 275 #endif
 276                 socklen_t err_size = sizeof(err);
 277
 278                 if (getsockopt(rpc->fd, SOL_SOCKET, SO_ERROR,
 279                                 (char *)&err, &err_size) != 0 || err != 0) {
 280                         if (err == 0) {
 281                                 err = errno;
 282                         }
 283                         rpc_set_error(rpc, "rpc_service: socket error "
 284                                                "%s(%d).",
 285                                                strerror(err), err);
 286                 } else {
 287                         rpc_set_error(rpc, "rpc_service: POLLERR, "
 288                                                 "Unknown socket error.");
 289                 }
 290                 if (rpc->connect_cb != NULL) {
 291                         rpc->connect_cb(rpc, RPC_STATUS_ERROR, rpc->error_string, rpc->connect_data);
 292                 }
 293                 return -1;
 294         }
 295         if (revents & POLLHUP) {
 296                 rpc_set_error(rpc, "Socket failed with POLLHUP");
 297                 if (rpc->connect_cb != NULL) {
 298                         rpc->connect_cb(rpc, RPC_STATUS_ERROR, rpc->error_string, rpc->connect_data);
 299                 }
 300                 return -1;
 301         }
 302
 303         if (rpc->is_connected == 0 && rpc->fd != -1 && revents&POLLOUT) {
 304                 int err = 0;
 305                 socklen_t err_size = sizeof(err);
 306
 307                 if (getsockopt(rpc->fd, SOL_SOCKET, SO_ERROR,
 308                                 (char *)&err, &err_size) != 0 || err != 0) {
 309                         if (err == 0) {
 310                                 err = errno;
 311                         }
 312                         rpc_set_error(rpc, "rpc_service: socket error "
 313                                         "%s(%d) while connecting.",
 314                                         strerror(err), err);
 315                         if (rpc->connect_cb != NULL) {
 316                                 rpc->connect_cb(rpc, RPC_STATUS_ERROR,
 317                                         NULL, rpc->connect_data);
 318                         }
 319                         return -1;
 320                 }
 321
 322                 rpc->is_connected = 1;
 323                 if (rpc->connect_cb != NULL) {
 324                         rpc->connect_cb(rpc, RPC_STATUS_SUCCESS, NULL, rpc->connect_data);
 325                 }
 326                 return 0;
 327         }
 328
 329         if (revents & POLLIN) {
 330                 if (rpc_read_from_socket(rpc) != 0) {
 331                         rpc_reconnect_requeue(rpc);
 332                         return 0;
 333                 }
 334         }
 335
 336         if (revents & POLLOUT && rpc->outqueue != NULL) {
 337                 if (rpc_write_to_socket(rpc) != 0) {
 338                         rpc_set_error(rpc, "write to socket failed");
 339                         return -1;
 340                 }
 341         }
 342
 343         return 0;
 344 }
 345
 346 void rpc_set_autoreconnect(struct rpc_context *rpc)
 347 {
 348         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 349
 350         rpc->auto_reconnect = 1;
 351 }
 352
 353 void rpc_unset_autoreconnect(struct rpc_context *rpc)
 354 {
 355         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 356
 357         rpc->auto_reconnect = 0;
 358 }
 359
 360 static int rpc_connect_sockaddr_async(struct rpc_context *rpc, struct sockaddr_storage *s)
 361 {
 362         int socksize;
 363
 364         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 365
 366         switch (s->ss_family) {
 367         case AF_INET:
 368                 socksize = sizeof(struct sockaddr_in);
 369                 rpc->fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
 370                 break;
 371         default:
 372                 rpc_set_error(rpc, "Can not handle AF_FAMILY:%d", s->ss_family);
 373                 return -1;
 374         }
 375
 376         if (rpc->fd == -1) {
 377                 rpc_set_error(rpc, "Failed to open socket");
 378                 return -1;
 379         }
 380
 381         /* Some systems allow you to set capabilities on an executable
 382          * to allow the file to be executed with privilege to bind to
 383          * privileged system ports, even if the user is not root.
 384          *
 385          * Opportunistically try to bind the socket to a low numbered
 386          * system port in the hope that the user is either root or the
 387          * executable has the CAP_NET_BIND_SERVICE.
 388          *
 389          * As soon as we fail the bind() with EACCES we know we will never
 390          * be able to bind to a system port so we terminate the loop.
 391          *
 392          * On linux, use
 393          *    sudo setcap 'cap_net_bind_service=+ep' /path/executable
 394          * to make the executable able to bind to a system port.
 395          *
 396          * On Windows, there is no concept of privileged ports. Thus
 397          * binding will usually succeed.
 398          */
 399         {
 400                 struct sockaddr_in sin;
 401                 static int portOfs = 0;
 402                 const int firstPort = 512;      /* >= 512 according to Sun docs */
 403                 const int portCount = IPPORT_RESERVED - firstPort;
 404                 int startOfs, port, rc;
 405
 406                 if (portOfs == 0) {
 407                         portOfs = time(NULL) % 400;
 408                 }
 409                 startOfs = portOfs;
 410                 do {
 411                         rc = -1;
 412                         port = htons(firstPort + portOfs);
 413                         portOfs = (portOfs + 1) % portCount;
 414
 415                         /* skip well-known ports */
 416                         if (!getservbyport(port, "tcp")) {
 417                                 memset(&sin, 0, sizeof(sin));
 418                                 sin.sin_port        = port;
 419                                 sin.sin_family      = AF_INET;
 420                                 sin.sin_addr.s_addr = 0;
 421
 422                                 rc = bind(rpc->fd, (struct sockaddr *)&sin, sizeof(struct sockaddr_in));
 423 #if !defined(WIN32)
 424                                 /* we got EACCES, so don't try again */
 425                                 if (rc != 0 && errno == EACCES)
 426                                         break;
 427 #endif
 428                         }
 429                 } while (rc != 0 && portOfs != startOfs);
 430         }
 431
 432         set_nonblocking(rpc->fd);
 433
 434         if (connect(rpc->fd, (struct sockaddr *)s, socksize) != 0 && errno != EINPROGRESS) {
 435                 rpc_set_error(rpc, "connect() to server failed. %s(%d)", strerror(errno), errno);
 436                 return -1;
 437         }
 438
 439         return 0;
 440 }
 441
 442 int rpc_connect_async(struct rpc_context *rpc, const char *server, int port, rpc_cb cb, void *private_data)
 443 {
 444         struct sockaddr_in *sin = (struct sockaddr_in *)&rpc->s;
 445
 446         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 447
 448         if (rpc->fd != -1) {
 449                 rpc_set_error(rpc, "Trying to connect while already connected");
 450                 return -1;
 451         }
 452
 453         if (rpc->is_udp != 0) {
 454                 rpc_set_error(rpc, "Trying to connect on UDP socket");
 455                 return -1;
 456         }
 457
 458         rpc->auto_reconnect = 0;
 459
 460         sin->sin_family = AF_INET;
 461         sin->sin_port   = htons(port);
 462         if (inet_pton(AF_INET, server, &sin->sin_addr) != 1) {
 463                 rpc_set_error(rpc, "Not a valid server ip address");
 464                 return -1;
 465         }
 466
 467
 468         switch (rpc->s.ss_family) {
 469         case AF_INET:
 470 #ifdef HAVE_SOCKADDR_LEN
 471                 sin->sin_len = sizeof(struct sockaddr_in);
 472 #endif
 473                 break;
 474         }
 475
 476         rpc->connect_cb  = cb;
 477         rpc->connect_data = private_data;
 478
 479         if (rpc_connect_sockaddr_async(rpc, &rpc->s) != 0) {
 480                 return -1;
 481         }
 482
 483         return 0;
 484 }
 485
 486 int rpc_disconnect(struct rpc_context *rpc, char *error)
 487 {
 488         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 489
 490         rpc_unset_autoreconnect(rpc);
 491
 492         if (rpc->fd != -1) {
 493                 close(rpc->fd);
 494         }
 495         rpc->fd  = -1;
 496
 497         rpc->is_connected = 0;
 498
 499         rpc_error_all_pdus(rpc, error);
 500
 501         return 0;
 502 }
 503
 504 static void reconnect_cb(struct rpc_context *rpc, int status, void *data _U_, void *private_data)
 505 {
 506         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 507
 508         if (status != RPC_STATUS_SUCCESS) {
 509                 rpc_error_all_pdus(rpc, "RPC ERROR: Failed to reconnect async");
 510                 return;
 511         }
 512
 513         rpc->is_connected = 1;
 514         rpc->connect_cb   = NULL;
 515 }
 516
 517 /* disconnect but do not error all PDUs, just move pdus in-flight back to the outqueue and reconnect */
 518 static int rpc_reconnect_requeue(struct rpc_context *rpc)
 519 {
 520         struct rpc_pdu *pdu;
 521
 522         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 523
 524         if (rpc->fd != -1) {
 525                 close(rpc->fd);
 526         }
 527         rpc->fd  = -1;
 528
 529         rpc->is_connected = 0;
 530
 531         /* socket is closed so we will not get any replies to any commands
 532          * in flight. Move them all over from the waitpdu queue back to the out queue
 533          */
 534         for (pdu=rpc->waitpdu; pdu; pdu=pdu->next) {
 535                 SLIST_REMOVE(&rpc->waitpdu, pdu);
 536                 SLIST_ADD(&rpc->outqueue, pdu);
 537                 /* we have to re-send the whole pdu again */
 538                 pdu->written = 0;
 539         }
 540
 541         if (rpc->auto_reconnect != 0) {
 542                 rpc->connect_cb  = reconnect_cb;
 543
 544                 if (rpc_connect_sockaddr_async(rpc, &rpc->s) != 0) {
 545                         rpc_error_all_pdus(rpc, "RPC ERROR: Failed to reconnect async");
 546                         return -1;
 547                 }
 548         }
 549
 550         return 0;
 551 }
 552
 553
 554 int rpc_bind_udp(struct rpc_context *rpc, char *addr, int port)
 555 {
 556         struct addrinfo *ai = NULL;
 557         char service[6];
 558
 559         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 560
 561         if (rpc->is_udp == 0) {
 562                 rpc_set_error(rpc, "Cant not bind UDP. Not UDP context");
 563                 return -1;
 564         }
 565
 566         sprintf(service, "%d", port);
 567         if (getaddrinfo(addr, service, NULL, &ai) != 0) {
 568                 rpc_set_error(rpc, "Invalid address:%s. "
 569                         "Can not resolv into IPv4/v6 structure.");
 570                 return -1;
 571         }
 572
 573         switch(ai->ai_family) {
 574         case AF_INET:
 575                 rpc->fd = socket(ai->ai_family, SOCK_DGRAM, 0);
 576                 if (rpc->fd == -1) {
 577                         rpc_set_error(rpc, "Failed to create UDP socket: %s", strerror(errno));
 578                         freeaddrinfo(ai);
 579                         return -1;
 580                 }
 581
 582                 if (bind(rpc->fd, (struct sockaddr *)ai->ai_addr, sizeof(struct sockaddr_in)) != 0) {
 583                         rpc_set_error(rpc, "Failed to bind to UDP socket: %s",strerror(errno));
 584                         freeaddrinfo(ai);
 585                         return -1;
 586                 }
 587                 break;
 588         default:
 589                 rpc_set_error(rpc, "Can not handle UPD sockets of family %d yet", ai->ai_family);
 590                 freeaddrinfo(ai);
 591                 return -1;
 592         }
 593
 594         freeaddrinfo(ai);
 595
 596         return 0;
 597 }
 598
 599 int rpc_set_udp_destination(struct rpc_context *rpc, char *addr, int port, int is_broadcast)
 600 {
 601         struct addrinfo *ai = NULL;
 602         char service[6];
 603
 604         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 605
 606         if (rpc->is_udp == 0) {
 607                 rpc_set_error(rpc, "Can not set destination sockaddr. Not UDP context");
 608                 return -1;
 609         }
 610
 611         sprintf(service, "%d", port);
 612         if (getaddrinfo(addr, service, NULL, &ai) != 0) {
 613                 rpc_set_error(rpc, "Invalid address:%s. "
 614                         "Can not resolv into IPv4/v6 structure.");
 615                 return -1;
 616         }
 617
 618         if (rpc->udp_dest) {
 619                 free(rpc->udp_dest);
 620                 rpc->udp_dest = NULL;
 621         }
 622         rpc->udp_dest = malloc(ai->ai_addrlen);
 623         if (rpc->udp_dest == NULL) {
 624                 rpc_set_error(rpc, "Out of memory. Failed to allocate sockaddr structure");
 625                 freeaddrinfo(ai);
 626                 return -1;
 627         }
 628         memcpy(rpc->udp_dest, ai->ai_addr, ai->ai_addrlen);
 629         freeaddrinfo(ai);
 630
 631         rpc->is_broadcast = is_broadcast;
 632         setsockopt(rpc->fd, SOL_SOCKET, SO_BROADCAST, (char *)&is_broadcast, sizeof(is_broadcast));
 633
 634         return 0;
 635 }
 636
 637 struct sockaddr *rpc_get_recv_sockaddr(struct rpc_context *rpc)
 638 {
 639         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 640
 641         return (struct sockaddr *)&rpc->udp_src;
 642 }
 643
 644 int rpc_queue_length(struct rpc_context *rpc)
 645 {
 646         int i=0;
 647         struct rpc_pdu *pdu;
 648
 649         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 650
 651         for(pdu = rpc->outqueue; pdu; pdu = pdu->next) {
 652                 i++;
 653         }
 654         for(pdu = rpc->waitpdu; pdu; pdu = pdu->next) {
 655                 i++;
 656         }
 657         return i;
 658 }