git.ozlabs.org Git - ccan/blob - ccan/iscsi/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 General Public License as published by
   6    the Free Software Foundation; either version 3 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 General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program; if not, see <http://www.gnu.org/licenses/>.
  16 */
  17
  18 #include <stdio.h>
  19 #include <stdlib.h>
  20 #include <string.h>
  21 #include <strings.h>
  22 #include <errno.h>
  23 #include <fcntl.h>
  24 #include <unistd.h>
  25 #include <netinet/in.h>
  26 #include <poll.h>
  27 #include <sys/ioctl.h>
  28 #include <arpa/inet.h>
  29 #include "iscsi.h"
  30 #include "iscsi-private.h"
  31 #include "dlinklist.h"
  32
  33 static void set_nonblocking(int fd)
  34 {
  35         unsigned v;
  36         v = fcntl(fd, F_GETFL, 0);
  37         fcntl(fd, F_SETFL, v | O_NONBLOCK);
  38 }
  39
  40 int iscsi_connect_async(struct iscsi_context *iscsi, const char *target, iscsi_command_cb cb, void *private_data)
  41 {
  42         int tpgt = -1;
  43         int port = 3260;
  44         char *str;
  45         char *addr;
  46         struct sockaddr_storage s;
  47         struct sockaddr_in *sin = (struct sockaddr_in *)&s;
  48         int socksize;
  49
  50         if (iscsi == NULL) {
  51                 printf("Trying to connect NULL context\n");
  52                 return -1;
  53         }
  54         if (iscsi->fd != -1) {
  55                 printf("Trying to connect but already connected\n");
  56                 return -2;
  57         }
  58
  59         addr = strdup(target);
  60         if (addr == NULL) {
  61                 printf("failed to strdup target address\n");
  62                 return -3;
  63         }
  64
  65         /* check if we have a target portal group tag */
  66         if ((str = rindex(addr, ',')) != NULL) {
  67                 tpgt = atoi(str+1);
  68                 str[0] = 0;
  69         }
  70
  71         /* XXX need handling for {ipv6 addresses} */
  72         /* for now, assume all is ipv4 */
  73         if ((str = rindex(addr, ':')) != NULL) {
  74                 port = atoi(str+1);
  75                 str[0] = 0;
  76         }
  77
  78         sin->sin_family = AF_INET;
  79         sin->sin_port   = htons(port);
  80         if (inet_pton(AF_INET, addr, &sin->sin_addr) != 1) {
  81                 printf("failed to convert to ip address\n");
  82                 free(addr);
  83                 return -4;
  84         }
  85         free(addr);
  86
  87         switch (s.ss_family) {
  88         case AF_INET:
  89                 iscsi->fd = socket(AF_INET, SOCK_STREAM, 0);
  90                 socksize = sizeof(struct sockaddr_in);
  91                 break;
  92         default:
  93                 printf("Unknown family :%d\n", s.ss_family);
  94                 return -5;
  95
  96         }
  97
  98         if (iscsi->fd == -1) {
  99                 printf("Failed to open socket\n");
 100                 return -6;
 101
 102         }
 103
 104         iscsi->connect_cb  = cb;
 105         iscsi->connect_data = private_data;
 106
 107         set_nonblocking(iscsi->fd);
 108
 109         if (connect(iscsi->fd, (struct sockaddr *)&s, socksize) != 0 && errno != EINPROGRESS) {
 110                 printf("Connect failed errno : %s (%d)\n", strerror(errno), errno);
 111                 return -7;
 112         }
 113
 114         return 0;
 115 }
 116
 117 int iscsi_disconnect(struct iscsi_context *iscsi)
 118 {
 119         if (iscsi == NULL) {
 120                 printf("Trying to disconnect NULL context\n");
 121                 return -1;
 122         }
 123         if (iscsi->is_loggedin != 0) {
 124                 printf("Trying to disconnect while logged in\n");
 125                 return -2;
 126         }
 127         if (iscsi->fd == -1) {
 128                 printf("Trying to disconnect but not connected\n");
 129                 return -3;
 130         }
 131
 132         close(iscsi->fd);
 133         iscsi->fd  = -1;
 134
 135         iscsi->is_connected = 0;
 136
 137         return 0;
 138 }
 139
 140 int iscsi_get_fd(struct iscsi_context *iscsi)
 141 {
 142         if (iscsi == NULL) {
 143                 printf("Trying to get fd for NULL context\n");
 144                 return -1;
 145         }
 146
 147         return iscsi->fd;
 148 }
 149
 150 int iscsi_which_events(struct iscsi_context *iscsi)
 151 {
 152         int events = POLLIN;
 153
 154         if (iscsi->is_connected == 0) {
 155                 events |= POLLOUT;
 156         }
 157
 158         if (iscsi->outqueue) {
 159                 events |= POLLOUT;
 160         }
 161         return events;
 162 }
 163
 164 static int iscsi_read_from_socket(struct iscsi_context *iscsi)
 165 {
 166         int available;
 167         int size;
 168         unsigned char *buf;
 169         ssize_t count;
 170
 171         if (ioctl(iscsi->fd, FIONREAD, &available) != 0) {
 172                 printf("ioctl FIONREAD returned error : %d\n", errno);
 173                 return -1;
 174         }
 175         if (available == 0) {
 176                 printf("no data readable in socket, socket is closed\n");
 177                 return -2;
 178         }
 179         size = iscsi->insize - iscsi->inpos + available;
 180         buf = malloc(size);
 181         if (buf == NULL) {
 182                 printf("failed to allocate %d bytes for input buffer\n", size);
 183                 return -3;
 184         }
 185         if (iscsi->insize > iscsi->inpos) {
 186                 memcpy(buf, iscsi->inbuf + iscsi->inpos, iscsi->insize - iscsi->inpos);
 187                 iscsi->insize -= iscsi->inpos;
 188                 iscsi->inpos   = 0;
 189         }
 190
 191         count = read(iscsi->fd, buf + iscsi->insize, available);
 192         if (count == -1) {
 193                 if (errno == EINTR) {
 194                         free(buf);
 195                         buf = NULL;
 196                         return 0;
 197                 }
 198                 printf("read from socket failed, errno:%d\n", errno);
 199                 free(buf);
 200                 buf = NULL;
 201                 return -4;
 202         }
 203
 204         if (iscsi->inbuf != NULL) {
 205                 free(iscsi->inbuf);
 206         }
 207         iscsi->inbuf   = buf;
 208         iscsi->insize += count;
 209
 210         while (1) {
 211                 if (iscsi->insize - iscsi->inpos < 48) {
 212                         return 0;
 213                 }
 214                 count = iscsi_get_pdu_size(iscsi->inbuf + iscsi->inpos);
 215                 if (iscsi->insize + iscsi->inpos < count) {
 216                         return 0;
 217                 }
 218                 if (iscsi_process_pdu(iscsi, iscsi->inbuf + iscsi->inpos, count) != 0) {
 219                         printf("failed to process pdu\n");
 220                         return -5;
 221                 }
 222                 iscsi->inpos += count;
 223                 if (iscsi->inpos == iscsi->insize) {
 224                         free(iscsi->inbuf);
 225                         iscsi->inbuf = NULL;
 226                         iscsi->insize = 0;
 227                         iscsi->inpos = 0;
 228                 }
 229                 if (iscsi->inpos > iscsi->insize) {
 230                         printf("inpos > insize. bug!\n");
 231                         return -6;
 232                 }
 233         }
 234
 235         return 0;
 236 }
 237
 238 static int iscsi_write_to_socket(struct iscsi_context *iscsi)
 239 {
 240         ssize_t count;
 241
 242         if (iscsi == NULL) {
 243                 printf("trying to write to socket for NULL context\n");
 244                 return -1;
 245         }
 246         if (iscsi->fd == -1) {
 247                 printf("trying to write but not connected\n");
 248                 return -2;
 249         }
 250
 251         while (iscsi->outqueue != NULL) {
 252                 ssize_t total;
 253
 254                 total = iscsi->outqueue->outdata.size;
 255                 total = (total +3) & 0xfffffffc;
 256
 257                 count = write(iscsi->fd, iscsi->outqueue->outdata.data + iscsi->outqueue->written, total - iscsi->outqueue->written);
 258                 if (count == -1) {
 259                         if (errno == EAGAIN || errno == EWOULDBLOCK) {
 260                                 printf("socket would block, return from write to socket\n");
 261                                 return 0;
 262                         }
 263                         printf("Error when writing to socket :%d\n", errno);
 264                         return -3;
 265                 }
 266
 267                 iscsi->outqueue->written += count;
 268                 if (iscsi->outqueue->written == total) {
 269                         struct iscsi_pdu *pdu = iscsi->outqueue;
 270
 271                         DLIST_REMOVE(iscsi->outqueue, pdu);
 272                         DLIST_ADD_END(iscsi->waitpdu, pdu, NULL);
 273                 }
 274         }
 275         return 0;
 276 }
 277
 278 int iscsi_service(struct iscsi_context *iscsi, int revents)
 279 {
 280         if (revents & POLLERR) {
 281                 printf("iscsi_service: POLLERR, socket error\n");
 282                 iscsi->connect_cb(iscsi, ISCSI_STATUS_ERROR, NULL, iscsi->connect_data);
 283                 return -1;
 284         }
 285         if (revents & POLLHUP) {
 286                 printf("iscsi_service: POLLHUP, socket error\n");
 287                 iscsi->connect_cb(iscsi, ISCSI_STATUS_ERROR, NULL, iscsi->connect_data);
 288                 return -2;
 289         }
 290
 291         if (iscsi->is_connected == 0 && iscsi->fd != -1 && revents&POLLOUT) {
 292                 iscsi->is_connected = 1;
 293                 iscsi->connect_cb(iscsi, ISCSI_STATUS_GOOD, NULL, iscsi->connect_data);
 294                 return 0;
 295         }
 296
 297         if (revents & POLLOUT && iscsi->outqueue != NULL) {
 298                 if (iscsi_write_to_socket(iscsi) != 0) {
 299                         printf("write to socket failed\n");
 300                         return -3;
 301                 }
 302         }
 303         if (revents & POLLIN) {
 304                 if (iscsi_read_from_socket(iscsi) != 0) {
 305                         printf("read from socket failed\n");
 306                         return -4;
 307                 }
 308         }
 309
 310         return 0;
 311 }
 312
 313 int iscsi_queue_pdu(struct iscsi_context *iscsi, struct iscsi_pdu *pdu)
 314 {
 315         if (iscsi == NULL) {
 316                 printf("trying to queue to NULL context\n");
 317                 return -1;
 318         }
 319         if (pdu == NULL) {
 320                 printf("trying to queue NULL pdu\n");
 321                 return -2;
 322         }
 323         DLIST_ADD_END(iscsi->outqueue, pdu, NULL);
 324
 325         return 0;
 326 }
 327
 328
 329