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
  18 #if defined(WIN32)
  19 #include <winsock2.h>
  20 #include <ws2tcpip.h>
  21 #include <basetsd.h>
  22 #define ssize_t SSIZE_T
  23 #define MSG_DONTWAIT 0
  24 #else
  25 #include <unistd.h>
  26 #include <poll.h>
  27 #include <arpa/inet.h>
  28 #include <sys/ioctl.h>
  29 #include <sys/socket.h>
  30 #include <netdb.h>
  31 #endif
  32
  33 #ifdef HAVE_CONFIG_H
  34 #include "config.h"
  35 #endif
  36 #include <stdio.h>
  37 #include <stdlib.h>
  38 #include <fcntl.h>
  39 #include <string.h>
  40 #include <errno.h>
  41 #include <rpc/rpc.h>
  42 #include <rpc/xdr.h>
  43 #ifdef HAVE_SYS_FILIO_H
  44 #include <sys/filio.h>
  45 #endif
  46 #include <sys/types.h>
  47 #include "libnfs.h"
  48 #include "libnfs-raw.h"
  49 #include "libnfs-private.h"
  50 #include "slist.h"
  51
  52 static int rpc_disconnect_requeue(struct rpc_context *rpc);
  53
  54 static void set_nonblocking(int fd)
  55 {
  56 #if defined(WIN32)
  57 #else
  58         unsigned v;
  59         v = fcntl(fd, F_GETFL, 0);
  60         fcntl(fd, F_SETFL, v | O_NONBLOCK);
  61 #endif
  62 }
  63
  64 int rpc_get_fd(struct rpc_context *rpc)
  65 {
  66         return rpc->fd;
  67 }
  68
  69 int rpc_which_events(struct rpc_context *rpc)
  70 {
  71         int events = rpc->is_connected ? POLLIN : POLLOUT;
  72
  73         if (rpc->is_udp != 0) {
  74                 /* for udp sockets we only wait for pollin */
  75                 return POLLIN;
  76         }
  77
  78         if (rpc->outqueue) {
  79                 events |= POLLOUT;
  80         }
  81         return events;
  82 }
  83
  84 static int rpc_write_to_socket(struct rpc_context *rpc)
  85 {
  86         ssize_t count;
  87
  88         if (rpc == NULL) {
  89                 return -1;
  90         }
  91         if (rpc->fd == -1) {
  92                 rpc_set_error(rpc, "trying to write but not connected");
  93                 return -1;
  94         }
  95
  96         while (rpc->outqueue != NULL) {
  97                 ssize_t total;
  98
  99                 total = rpc->outqueue->outdata.size;
 100
 101 #if defined(WIN32)
 102                 count = send(rpc->fd, rpc->outqueue->outdata.data + rpc->outqueue->written, total - rpc->outqueue->written, 0);
 103 #else
 104                 count = write(rpc->fd, rpc->outqueue->outdata.data + rpc->outqueue->written, total - rpc->outqueue->written);
 105 #endif
 106                 if (count == -1) {
 107                         if (errno == EAGAIN || errno == EWOULDBLOCK) {
 108                                 return 0;
 109                         }
 110                         rpc_set_error(rpc, "Error when writing to socket :%s(%d)", strerror(errno), errno);
 111                         return -1;
 112                 }
 113
 114                 rpc->outqueue->written += count;
 115                 if (rpc->outqueue->written == total) {
 116                         struct rpc_pdu *pdu = rpc->outqueue;
 117
 118                         SLIST_REMOVE(&rpc->outqueue, pdu);
 119                         SLIST_ADD_END(&rpc->waitpdu, pdu);
 120                 }
 121         }
 122         return 0;
 123 }
 124
 125 static int rpc_read_from_socket(struct rpc_context *rpc)
 126 {
 127         int available;
 128         int size;
 129         int pdu_size;
 130         ssize_t count;
 131
 132 #if defined(WIN32)
 133         if (ioctlsocket(rpc->fd, FIONREAD, &available) != 0) {
 134 #else
 135         if (ioctl(rpc->fd, FIONREAD, &available) != 0) {
 136 #endif
 137                 rpc_set_error(rpc, "Ioctl FIONREAD returned error : %d. Closing socket.", errno);
 138                 return -1;
 139         }
 140         if (available == 0) {
 141                 rpc_set_error(rpc, "Socket has been closed");
 142                 return -1;
 143         }
 144
 145         if (rpc->is_udp) {
 146                 char *buf;
 147                 socklen_t socklen = sizeof(rpc->udp_src);
 148
 149                 buf = malloc(available);
 150                 if (buf == NULL) {
 151                         rpc_set_error(rpc, "Failed to malloc buffer for recvfrom");
 152                         return -1;
 153                 }
 154                 count = recvfrom(rpc->fd, buf, available, MSG_DONTWAIT, (struct sockaddr *)&rpc->udp_src, &socklen);
 155                 if (count < 0) {
 156                         rpc_set_error(rpc, "Failed recvfrom: %s", strerror(errno));
 157                         free(buf);
 158                 }
 159                 if (rpc_process_pdu(rpc, buf, count) != 0) {
 160                         rpc_set_error(rpc, "Invalid/garbage pdu received from server. Ignoring PDU");
 161                         free(buf);
 162                         return -1;
 163                 }
 164                 free(buf);
 165                 return 0;
 166         }
 167
 168         /* read record marker, 4 bytes at the beginning of every pdu */
 169         if (rpc->inbuf == NULL) {
 170                 rpc->insize = 4;
 171                 rpc->inbuf = malloc(rpc->insize);
 172                 if (rpc->inbuf == NULL) {
 173                         rpc_set_error(rpc, "Failed to allocate buffer for record marker, errno:%d. Closing socket.", errno);
 174                         return -1;
 175                 }
 176         }
 177         if (rpc->inpos < 4) {
 178                 size = 4 - rpc->inpos;
 179
 180 #if defined(WIN32)
 181                 count = recv(rpc->fd, rpc->inbuf + rpc->inpos, size, 0);
 182 #else
 183                 count = read(rpc->fd, rpc->inbuf + rpc->inpos, size);
 184 #endif
 185                 if (count == -1) {
 186                         if (errno == EINTR) {
 187                                 return 0;
 188                         }
 189                         rpc_set_error(rpc, "Read from socket failed, errno:%d. Closing socket.", errno);
 190                         return -1;
 191                 }
 192                 available  -= count;
 193                 rpc->inpos += count;
 194         }
 195
 196         if (available == 0) {
 197                 return 0;
 198         }
 199
 200         pdu_size = rpc_get_pdu_size(rpc->inbuf);
 201         if (rpc->insize < pdu_size) {
 202                 unsigned char *buf;
 203
 204                 buf = malloc(pdu_size);
 205                 if (buf == NULL) {
 206                         rpc_set_error(rpc, "Failed to allocate buffer of %d bytes for pdu, errno:%d. Closing socket.", pdu_size, errno);
 207                         return -1;
 208                 }
 209                 memcpy(buf, rpc->inbuf, rpc->insize);
 210                 free(rpc->inbuf);
 211                 rpc->inbuf  = buf;
 212                 rpc->insize = rpc_get_pdu_size(rpc->inbuf);
 213         }
 214
 215         size = available;
 216         if (size > rpc->insize - rpc->inpos) {
 217                 size = rpc->insize - rpc->inpos;
 218         }
 219
 220 #if defined(WIN32)
 221         count = recv(rpc->fd, rpc->inbuf + rpc->inpos, size, 0);
 222 #else
 223         count = read(rpc->fd, rpc->inbuf + rpc->inpos, size);
 224 #endif
 225         if (count == -1) {
 226                 if (errno == EINTR) {
 227                         return 0;
 228                 }
 229                 rpc_set_error(rpc, "Read from socket failed, errno:%d. Closing socket.", errno);
 230                 return -1;
 231         }
 232         available  -= count;
 233         rpc->inpos += count;
 234
 235         if (rpc->inpos == rpc->insize) {
 236                 if (rpc_process_pdu(rpc, rpc->inbuf, pdu_size) != 0) {
 237                         rpc_set_error(rpc, "Invalid/garbage pdu received from server. Closing socket");
 238                         return -1;
 239                 }
 240                 free(rpc->inbuf);
 241                 rpc->inbuf  = NULL;
 242                 rpc->insize = 0;
 243                 rpc->inpos  = 0;
 244         }
 245
 246         return 0;
 247 }
 248
 249
 250
 251 int rpc_service(struct rpc_context *rpc, int revents)
 252 {
 253         if (revents & POLLERR) {
 254                 int err = 0;
 255                 socklen_t err_size = sizeof(err);
 256
 257                 if (getsockopt(rpc->fd, SOL_SOCKET, SO_ERROR,
 258                                 &err, &err_size) != 0 || err != 0) {
 259                         if (err == 0) {
 260                                 err = errno;
 261                         }
 262                         rpc_set_error(rpc, "rpc_service: socket error "
 263                                                "%s(%d).",
 264                                                strerror(err), err);
 265                 } else {
 266                         rpc_set_error(rpc, "rpc_service: POLLERR, "
 267                                                 "Unknown socket error.");
 268                 }
 269                 rpc->connect_cb(rpc, RPC_STATUS_ERROR, rpc->error_string, rpc->connect_data);
 270                 return -1;
 271         }
 272         if (revents & POLLHUP) {
 273                 rpc_set_error(rpc, "Socket failed with POLLHUP");
 274                 rpc->connect_cb(rpc, RPC_STATUS_ERROR, rpc->error_string, rpc->connect_data);
 275                 return -1;
 276         }
 277
 278         if (rpc->is_connected == 0 && rpc->fd != -1 && revents&POLLOUT) {
 279                 int err = 0;
 280                 socklen_t err_size = sizeof(err);
 281
 282                 if (getsockopt(rpc->fd, SOL_SOCKET, SO_ERROR,
 283                                 &err, &err_size) != 0 || err != 0) {
 284                         if (err == 0) {
 285                                 err = errno;
 286                         }
 287                         rpc_set_error(rpc, "rpc_service: socket error "
 288                                         "%s(%d) while connecting.",
 289                                         strerror(err), err);
 290                         rpc->connect_cb(rpc, RPC_STATUS_ERROR,
 291                                         NULL, rpc->connect_data);
 292                         return -1;
 293                 }
 294
 295                 rpc->is_connected = 1;
 296                 rpc->connect_cb(rpc, RPC_STATUS_SUCCESS, NULL, rpc->connect_data);
 297                 return 0;
 298         }
 299
 300         if (revents & POLLIN) {
 301                 if (rpc_read_from_socket(rpc) != 0) {
 302                         rpc_disconnect_requeue(rpc);
 303                         return 0;
 304                 }
 305         }
 306
 307         if (revents & POLLOUT && rpc->outqueue != NULL) {
 308                 if (rpc_write_to_socket(rpc) != 0) {
 309                         rpc_set_error(rpc, "write to socket failed");
 310                         return -1;
 311                 }
 312         }
 313
 314         return 0;
 315 }
 316
 317
 318 int rpc_connect_async(struct rpc_context *rpc, const char *server, int port, rpc_cb cb, void *private_data)
 319 {
 320         struct sockaddr_storage s;
 321         struct sockaddr_in *sin = (struct sockaddr_in *)&s;
 322         int socksize;
 323
 324         if (rpc->fd != -1) {
 325                 rpc_set_error(rpc, "Trying to connect while already connected");
 326                 return -1;
 327         }
 328
 329         if (rpc->is_udp != 0) {
 330                 rpc_set_error(rpc, "Trying to connect on UDP socket");
 331                 return -1;
 332         }
 333
 334         sin->sin_family = AF_INET;
 335         sin->sin_port   = htons(port);
 336         if (inet_pton(AF_INET, server, &sin->sin_addr) != 1) {
 337                 rpc_set_error(rpc, "Not a valid server ip address");
 338                 return -1;
 339         }
 340
 341         switch (s.ss_family) {
 342         case AF_INET:
 343                 socksize = sizeof(struct sockaddr_in);
 344 #ifdef HAVE_SOCKADDR_LEN
 345                 sin->sin_len = socksize;
 346 #endif
 347                 rpc->fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
 348                 break;
 349         }
 350
 351         if (rpc->fd == -1) {
 352                 rpc_set_error(rpc, "Failed to open socket");
 353                 return -1;
 354         }
 355
 356         rpc->connect_cb  = cb;
 357         rpc->connect_data = private_data;
 358
 359         set_nonblocking(rpc->fd);
 360
 361         if (connect(rpc->fd, (struct sockaddr *)&s, socksize) != 0 && errno != EINPROGRESS) {
 362                 rpc_set_error(rpc, "connect() to server failed");
 363                 return -1;
 364         }
 365
 366         return 0;
 367 }
 368
 369 int rpc_disconnect(struct rpc_context *rpc, char *error)
 370 {
 371         if (rpc->fd != -1) {
 372 #if defined(WIN32)
 373                 closesocket(rpc->fd);
 374 #else
 375                 close(rpc->fd);
 376 #endif
 377         }
 378         rpc->fd  = -1;
 379
 380         rpc->is_connected = 0;
 381
 382         rpc_error_all_pdus(rpc, error);
 383
 384         return 0;
 385 }
 386
 387 /* disconnect but do not error all PDUs, just move pdus in-flight back to the outqueue */
 388 static int rpc_disconnect_requeue(struct rpc_context *rpc)
 389 {
 390         struct rpc_pdu *pdu;
 391
 392         if (rpc->fd != -1) {
 393 #if defined(WIN32)
 394                 closesocket(rpc->fd);
 395 #else
 396                 close(rpc->fd);
 397 #endif
 398         }
 399         rpc->fd  = -1;
 400
 401         rpc->is_connected = 0;
 402
 403         /* socket is closed so we will not get any replies to any commands
 404          * in flight. Move them all over from the waitpdu queue back to the out queue
 405          */
 406         for (pdu=rpc->waitpdu; pdu; pdu=pdu->next) {
 407                 SLIST_REMOVE(&rpc->waitpdu, pdu);
 408                 SLIST_ADD(&rpc->outqueue, pdu);
 409         }
 410
 411         return 0;
 412 }
 413
 414
 415 int rpc_bind_udp(struct rpc_context *rpc, char *addr, int port)
 416 {
 417         struct addrinfo *ai = NULL;
 418         char service[6];
 419
 420         if (rpc->is_udp == 0) {
 421                 rpc_set_error(rpc, "Cant not bind UDP. Not UDP context");
 422                 return -1;
 423         }
 424
 425         sprintf(service, "%d", port);
 426         if (getaddrinfo(addr, service, NULL, &ai) != 0) {
 427                 rpc_set_error(rpc, "Invalid address:%s. "
 428                         "Can not resolv into IPv4/v6 structure.");
 429                 return -1;
 430         }
 431
 432         switch(ai->ai_family) {
 433         case AF_INET:
 434                 rpc->fd = socket(ai->ai_family, SOCK_DGRAM, 0);
 435                 if (rpc->fd == -1) {
 436                         rpc_set_error(rpc, "Failed to create UDP socket: %s", strerror(errno));
 437                         freeaddrinfo(ai);
 438                         return -1;
 439                 }
 440
 441                 if (bind(rpc->fd, (struct sockaddr *)ai->ai_addr, sizeof(struct sockaddr_in)) != 0) {
 442                         rpc_set_error(rpc, "Failed to bind to UDP socket: %s",strerror(errno));
 443                         freeaddrinfo(ai);
 444                         return -1;
 445                 }
 446                 break;
 447         default:
 448                 rpc_set_error(rpc, "Can not handle UPD sockets of family %d yet", ai->ai_family);
 449                 freeaddrinfo(ai);
 450                 return -1;
 451         }
 452
 453         freeaddrinfo(ai);
 454
 455         return 0;
 456 }
 457
 458 int rpc_set_udp_destination(struct rpc_context *rpc, char *addr, int port, int is_broadcast)
 459 {
 460         struct addrinfo *ai = NULL;
 461         char service[6];
 462
 463         if (rpc->is_udp == 0) {
 464                 rpc_set_error(rpc, "Can not set destination sockaddr. Not UDP context");
 465                 return -1;
 466         }
 467
 468         sprintf(service, "%d", port);
 469         if (getaddrinfo(addr, service, NULL, &ai) != 0) {
 470                 rpc_set_error(rpc, "Invalid address:%s. "
 471                         "Can not resolv into IPv4/v6 structure.");
 472                 return -1;
 473         }
 474
 475         if (rpc->udp_dest) {
 476                 free(rpc->udp_dest);
 477                 rpc->udp_dest = NULL;
 478         }
 479         rpc->udp_dest = malloc(ai->ai_addrlen);
 480         if (rpc->udp_dest == NULL) {
 481                 rpc_set_error(rpc, "Out of memory. Failed to allocate sockaddr structure");
 482                 return -1;
 483         }
 484         memcpy(rpc->udp_dest, ai->ai_addr, ai->ai_addrlen);
 485         freeaddrinfo(ai);
 486
 487         rpc->is_broadcast = is_broadcast;
 488         setsockopt(rpc->fd, SOL_SOCKET, SO_BROADCAST, &is_broadcast, sizeof(is_broadcast));
 489
 490         return 0;
 491 }
 492
 493 struct sockaddr *rpc_get_recv_sockaddr(struct rpc_context *rpc)
 494 {
 495         return (struct sockaddr *)&rpc->udp_src;
 496 }