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 "config.h"
  19 #include <stdio.h>
  20 #include <stdlib.h>
  21 #include <string.h>
  22 #include <strings.h>
  23 #include <errno.h>
  24 #include <fcntl.h>
  25 #include <unistd.h>
  26 #include <netinet/in.h>
  27 #include <poll.h>
  28 #include <sys/ioctl.h>
  29 #include <sys/types.h>
  30 #include <sys/socket.h>
  31 #include <arpa/inet.h>
  32 #include "iscsi.h"
  33 #include "iscsi-private.h"
  34 #include "dlinklist.h"
  35 #if HAVE_SYS_FILIO_H
  36 #include <sys/filio.h>
  37 #endif
  38
  39 static void set_nonblocking(int fd)
  40 {
  41         unsigned v;
  42         v = fcntl(fd, F_GETFL, 0);
  43         fcntl(fd, F_SETFL, v | O_NONBLOCK);
  44 }
  45
  46 int iscsi_connect_async(struct iscsi_context *iscsi, const char *target, iscsi_command_cb cb, void *private_data)
  47 {
  48         int port = 3260;
  49         char *str;
  50         char *addr;
  51         union {
  52                 struct sockaddr sa;
  53                 struct sockaddr_storage ss;
  54                 struct sockaddr_in sin;
  55         } s;
  56         int socksize;
  57
  58         if (iscsi == NULL) {
  59                 printf("Trying to connect NULL context\n");
  60                 return -1;
  61         }
  62         if (iscsi->fd != -1) {
  63                 printf("Trying to connect but already connected\n");
  64                 return -2;
  65         }
  66
  67         addr = strdup(target);
  68         if (addr == NULL) {
  69                 printf("failed to strdup target address\n");
  70                 return -3;
  71         }
  72
  73         /* check if we have a target portal group tag */
  74         if ((str = rindex(addr, ',')) != NULL) {
  75                 str[0] = 0;
  76         }
  77
  78         /* XXX need handling for {ipv6 addresses} */
  79         /* for now, assume all is ipv4 */
  80         if ((str = rindex(addr, ':')) != NULL) {
  81                 port = atoi(str+1);
  82                 str[0] = 0;
  83         }
  84
  85         s.sin.sin_family = AF_INET;
  86         s.sin.sin_port   = htons(port);
  87         if (inet_pton(AF_INET, addr, &s.sin.sin_addr) != 1) {
  88                 printf("failed to convert to ip address\n");
  89                 free(addr);
  90                 return -4;
  91         }
  92         free(addr);
  93
  94         switch (s.ss.ss_family) {
  95         case AF_INET:
  96                 iscsi->fd = socket(AF_INET, SOCK_STREAM, 0);
  97                 socksize = sizeof(struct sockaddr_in);
  98                 break;
  99         default:
 100                 printf("Unknown family :%d\n", s.ss.ss_family);
 101                 return -5;
 102
 103         }
 104
 105         if (iscsi->fd == -1) {
 106                 printf("Failed to open socket\n");
 107                 return -6;
 108
 109         }
 110
 111         iscsi->connect_cb  = cb;
 112         iscsi->connect_data = private_data;
 113
 114         set_nonblocking(iscsi->fd);
 115
 116         if (connect(iscsi->fd, &s.sa, socksize) != 0 && errno != EINPROGRESS) {
 117                 printf("Connect failed errno : %s (%d)\n", strerror(errno), errno);
 118                 return -7;
 119         }
 120
 121         return 0;
 122 }
 123
 124 int iscsi_disconnect(struct iscsi_context *iscsi)
 125 {
 126         if (iscsi == NULL) {
 127                 printf("Trying to disconnect NULL context\n");
 128                 return -1;
 129         }
 130         if (iscsi->is_loggedin != 0) {
 131                 printf("Trying to disconnect while logged in\n");
 132                 return -2;
 133         }
 134         if (iscsi->fd == -1) {
 135                 printf("Trying to disconnect but not connected\n");
 136                 return -3;
 137         }
 138
 139         close(iscsi->fd);
 140         iscsi->fd  = -1;
 141
 142         iscsi->is_connected = 0;
 143
 144         return 0;
 145 }
 146
 147 int iscsi_get_fd(struct iscsi_context *iscsi)
 148 {
 149         if (iscsi == NULL) {
 150                 printf("Trying to get fd for NULL context\n");
 151                 return -1;
 152         }
 153
 154         return iscsi->fd;
 155 }
 156
 157 int iscsi_which_events(struct iscsi_context *iscsi)
 158 {
 159         int events = POLLIN;
 160
 161         if (iscsi->is_connected == 0) {
 162                 events |= POLLOUT;
 163         }
 164
 165         if (iscsi->outqueue) {
 166                 events |= POLLOUT;
 167         }
 168         return events;
 169 }
 170
 171 static int iscsi_read_from_socket(struct iscsi_context *iscsi)
 172 {
 173         int available;
 174         int size;
 175         unsigned char *buf;
 176         ssize_t count;
 177
 178         if (ioctl(iscsi->fd, FIONREAD, &available) != 0) {
 179                 printf("ioctl FIONREAD returned error : %d\n", errno);
 180                 return -1;
 181         }
 182         if (available == 0) {
 183                 printf("no data readable in socket, socket is closed\n");
 184                 return -2;
 185         }
 186         size = iscsi->insize - iscsi->inpos + available;
 187         buf = malloc(size);
 188         if (buf == NULL) {
 189                 printf("failed to allocate %d bytes for input buffer\n", size);
 190                 return -3;
 191         }
 192         if (iscsi->insize > iscsi->inpos) {
 193                 memcpy(buf, iscsi->inbuf + iscsi->inpos, iscsi->insize - iscsi->inpos);
 194                 iscsi->insize -= iscsi->inpos;
 195                 iscsi->inpos   = 0;
 196         }
 197
 198         count = read(iscsi->fd, buf + iscsi->insize, available);
 199         if (count == -1) {
 200                 if (errno == EINTR) {
 201                         free(buf);
 202                         buf = NULL;
 203                         return 0;
 204                 }
 205                 printf("read from socket failed, errno:%d\n", errno);
 206                 free(buf);
 207                 buf = NULL;
 208                 return -4;
 209         }
 210
 211         if (iscsi->inbuf != NULL) {
 212                 free(iscsi->inbuf);
 213         }
 214         iscsi->inbuf   = buf;
 215         iscsi->insize += count;
 216
 217         while (1) {
 218                 if (iscsi->insize - iscsi->inpos < 48) {
 219                         return 0;
 220                 }
 221                 count = iscsi_get_pdu_size(iscsi->inbuf + iscsi->inpos);
 222                 if (iscsi->insize + iscsi->inpos < count) {
 223                         return 0;
 224                 }
 225                 if (iscsi_process_pdu(iscsi, iscsi->inbuf + iscsi->inpos, count) != 0) {
 226                         printf("failed to process pdu\n");
 227                         return -5;
 228                 }
 229                 iscsi->inpos += count;
 230                 if (iscsi->inpos == iscsi->insize) {
 231                         free(iscsi->inbuf);
 232                         iscsi->inbuf = NULL;
 233                         iscsi->insize = 0;
 234                         iscsi->inpos = 0;
 235                 }
 236                 if (iscsi->inpos > iscsi->insize) {
 237                         printf("inpos > insize. bug!\n");
 238                         return -6;
 239                 }
 240         }
 241
 242         return 0;
 243 }
 244
 245 static int iscsi_write_to_socket(struct iscsi_context *iscsi)
 246 {
 247         ssize_t count;
 248
 249         if (iscsi == NULL) {
 250                 printf("trying to write to socket for NULL context\n");
 251                 return -1;
 252         }
 253         if (iscsi->fd == -1) {
 254                 printf("trying to write but not connected\n");
 255                 return -2;
 256         }
 257
 258         while (iscsi->outqueue != NULL) {
 259                 ssize_t total;
 260
 261                 total = iscsi->outqueue->outdata.size;
 262                 total = (total +3) & 0xfffffffc;
 263
 264                 count = write(iscsi->fd, iscsi->outqueue->outdata.data + iscsi->outqueue->written, total - iscsi->outqueue->written);
 265                 if (count == -1) {
 266                         if (errno == EAGAIN || errno == EWOULDBLOCK) {
 267                                 printf("socket would block, return from write to socket\n");
 268                                 return 0;
 269                         }
 270                         printf("Error when writing to socket :%d\n", errno);
 271                         return -3;
 272                 }
 273
 274                 iscsi->outqueue->written += count;
 275                 if (iscsi->outqueue->written == total) {
 276                         struct iscsi_pdu *pdu = iscsi->outqueue;
 277
 278                         DLIST_REMOVE(iscsi->outqueue, pdu);
 279                         DLIST_ADD_END(iscsi->waitpdu, pdu, NULL);
 280                 }
 281         }
 282         return 0;
 283 }
 284
 285 int iscsi_service(struct iscsi_context *iscsi, int revents)
 286 {
 287         if (revents & POLLERR) {
 288                 printf("iscsi_service: POLLERR, socket error\n");
 289                 iscsi->connect_cb(iscsi, ISCSI_STATUS_ERROR, NULL, iscsi->connect_data);
 290                 return -1;
 291         }
 292         if (revents & POLLHUP) {
 293                 printf("iscsi_service: POLLHUP, socket error\n");
 294                 iscsi->connect_cb(iscsi, ISCSI_STATUS_ERROR, NULL, iscsi->connect_data);
 295                 return -2;
 296         }
 297
 298         if (iscsi->is_connected == 0 && iscsi->fd != -1 && revents&POLLOUT) {
 299                 iscsi->is_connected = 1;
 300                 iscsi->connect_cb(iscsi, ISCSI_STATUS_GOOD, NULL, iscsi->connect_data);
 301                 return 0;
 302         }
 303
 304         if (revents & POLLOUT && iscsi->outqueue != NULL) {
 305                 if (iscsi_write_to_socket(iscsi) != 0) {
 306                         printf("write to socket failed\n");
 307                         return -3;
 308                 }
 309         }
 310         if (revents & POLLIN) {
 311                 if (iscsi_read_from_socket(iscsi) != 0) {
 312                         printf("read from socket failed\n");
 313                         return -4;
 314                 }
 315         }
 316
 317         return 0;
 318 }
 319
 320 int iscsi_queue_pdu(struct iscsi_context *iscsi, struct iscsi_pdu *pdu)
 321 {
 322         if (iscsi == NULL) {
 323                 printf("trying to queue to NULL context\n");
 324                 return -1;
 325         }
 326         if (pdu == NULL) {
 327                 printf("trying to queue NULL pdu\n");
 328                 return -2;
 329         }
 330         DLIST_ADD_END(iscsi->outqueue, pdu, NULL);
 331
 332         return 0;
 333 }
 334
 335
 336