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 tpgt = -1;
  49         int port = 3260;
  50         char *str;
  51         char *addr;
  52         union {
  53                 struct sockaddr sa;
  54                 struct sockaddr_storage ss;
  55                 struct sockaddr_in sin;
  56         } s;
  57         int socksize;
  58
  59         if (iscsi == NULL) {
  60                 printf("Trying to connect NULL context\n");
  61                 return -1;
  62         }
  63         if (iscsi->fd != -1) {
  64                 printf("Trying to connect but already connected\n");
  65                 return -2;
  66         }
  67
  68         addr = strdup(target);
  69         if (addr == NULL) {
  70                 printf("failed to strdup target address\n");
  71                 return -3;
  72         }
  73
  74         /* check if we have a target portal group tag */
  75         if ((str = rindex(addr, ',')) != NULL) {
  76                 tpgt = atoi(str+1);
  77                 str[0] = 0;
  78         }
  79
  80         /* XXX need handling for {ipv6 addresses} */
  81         /* for now, assume all is ipv4 */
  82         if ((str = rindex(addr, ':')) != NULL) {
  83                 port = atoi(str+1);
  84                 str[0] = 0;
  85         }
  86
  87         s.sin.sin_family = AF_INET;
  88         s.sin.sin_port   = htons(port);
  89         if (inet_pton(AF_INET, addr, &s.sin.sin_addr) != 1) {
  90                 printf("failed to convert to ip address\n");
  91                 free(addr);
  92                 return -4;
  93         }
  94         free(addr);
  95
  96         switch (s.ss.ss_family) {
  97         case AF_INET:
  98                 iscsi->fd = socket(AF_INET, SOCK_STREAM, 0);
  99                 socksize = sizeof(struct sockaddr_in);
 100                 break;
 101         default:
 102                 printf("Unknown family :%d\n", s.ss.ss_family);
 103                 return -5;
 104
 105         }
 106
 107         if (iscsi->fd == -1) {
 108                 printf("Failed to open socket\n");
 109                 return -6;
 110
 111         }
 112
 113         iscsi->connect_cb  = cb;
 114         iscsi->connect_data = private_data;
 115
 116         set_nonblocking(iscsi->fd);
 117
 118         if (connect(iscsi->fd, &s.sa, socksize) != 0 && errno != EINPROGRESS) {
 119                 printf("Connect failed errno : %s (%d)\n", strerror(errno), errno);
 120                 return -7;
 121         }
 122
 123         return 0;
 124 }
 125
 126 int iscsi_disconnect(struct iscsi_context *iscsi)
 127 {
 128         if (iscsi == NULL) {
 129                 printf("Trying to disconnect NULL context\n");
 130                 return -1;
 131         }
 132         if (iscsi->is_loggedin != 0) {
 133                 printf("Trying to disconnect while logged in\n");
 134                 return -2;
 135         }
 136         if (iscsi->fd == -1) {
 137                 printf("Trying to disconnect but not connected\n");
 138                 return -3;
 139         }
 140
 141         close(iscsi->fd);
 142         iscsi->fd  = -1;
 143
 144         iscsi->is_connected = 0;
 145
 146         return 0;
 147 }
 148
 149 int iscsi_get_fd(struct iscsi_context *iscsi)
 150 {
 151         if (iscsi == NULL) {
 152                 printf("Trying to get fd for NULL context\n");
 153                 return -1;
 154         }
 155
 156         return iscsi->fd;
 157 }
 158
 159 int iscsi_which_events(struct iscsi_context *iscsi)
 160 {
 161         int events = POLLIN;
 162
 163         if (iscsi->is_connected == 0) {
 164                 events |= POLLOUT;
 165         }
 166
 167         if (iscsi->outqueue) {
 168                 events |= POLLOUT;
 169         }
 170         return events;
 171 }
 172
 173 static int iscsi_read_from_socket(struct iscsi_context *iscsi)
 174 {
 175         int available;
 176         int size;
 177         unsigned char *buf;
 178         ssize_t count;
 179
 180         if (ioctl(iscsi->fd, FIONREAD, &available) != 0) {
 181                 printf("ioctl FIONREAD returned error : %d\n", errno);
 182                 return -1;
 183         }
 184         if (available == 0) {
 185                 printf("no data readable in socket, socket is closed\n");
 186                 return -2;
 187         }
 188         size = iscsi->insize - iscsi->inpos + available;
 189         buf = malloc(size);
 190         if (buf == NULL) {
 191                 printf("failed to allocate %d bytes for input buffer\n", size);
 192                 return -3;
 193         }
 194         if (iscsi->insize > iscsi->inpos) {
 195                 memcpy(buf, iscsi->inbuf + iscsi->inpos, iscsi->insize - iscsi->inpos);
 196                 iscsi->insize -= iscsi->inpos;
 197                 iscsi->inpos   = 0;
 198         }
 199
 200         count = read(iscsi->fd, buf + iscsi->insize, available);
 201         if (count == -1) {
 202                 if (errno == EINTR) {
 203                         free(buf);
 204                         buf = NULL;
 205                         return 0;
 206                 }
 207                 printf("read from socket failed, errno:%d\n", errno);
 208                 free(buf);
 209                 buf = NULL;
 210                 return -4;
 211         }
 212
 213         if (iscsi->inbuf != NULL) {
 214                 free(iscsi->inbuf);
 215         }
 216         iscsi->inbuf   = buf;
 217         iscsi->insize += count;
 218
 219         while (1) {
 220                 if (iscsi->insize - iscsi->inpos < 48) {
 221                         return 0;
 222                 }
 223                 count = iscsi_get_pdu_size(iscsi->inbuf + iscsi->inpos);
 224                 if (iscsi->insize + iscsi->inpos < count) {
 225                         return 0;
 226                 }
 227                 if (iscsi_process_pdu(iscsi, iscsi->inbuf + iscsi->inpos, count) != 0) {
 228                         printf("failed to process pdu\n");
 229                         return -5;
 230                 }
 231                 iscsi->inpos += count;
 232                 if (iscsi->inpos == iscsi->insize) {
 233                         free(iscsi->inbuf);
 234                         iscsi->inbuf = NULL;
 235                         iscsi->insize = 0;
 236                         iscsi->inpos = 0;
 237                 }
 238                 if (iscsi->inpos > iscsi->insize) {
 239                         printf("inpos > insize. bug!\n");
 240                         return -6;
 241                 }
 242         }
 243
 244         return 0;
 245 }
 246
 247 static int iscsi_write_to_socket(struct iscsi_context *iscsi)
 248 {
 249         ssize_t count;
 250
 251         if (iscsi == NULL) {
 252                 printf("trying to write to socket for NULL context\n");
 253                 return -1;
 254         }
 255         if (iscsi->fd == -1) {
 256                 printf("trying to write but not connected\n");
 257                 return -2;
 258         }
 259
 260         while (iscsi->outqueue != NULL) {
 261                 ssize_t total;
 262
 263                 total = iscsi->outqueue->outdata.size;
 264                 total = (total +3) & 0xfffffffc;
 265
 266                 count = write(iscsi->fd, iscsi->outqueue->outdata.data + iscsi->outqueue->written, total - iscsi->outqueue->written);
 267                 if (count == -1) {
 268                         if (errno == EAGAIN || errno == EWOULDBLOCK) {
 269                                 printf("socket would block, return from write to socket\n");
 270                                 return 0;
 271                         }
 272                         printf("Error when writing to socket :%d\n", errno);
 273                         return -3;
 274                 }
 275
 276                 iscsi->outqueue->written += count;
 277                 if (iscsi->outqueue->written == total) {
 278                         struct iscsi_pdu *pdu = iscsi->outqueue;
 279
 280                         DLIST_REMOVE(iscsi->outqueue, pdu);
 281                         DLIST_ADD_END(iscsi->waitpdu, pdu, NULL);
 282                 }
 283         }
 284         return 0;
 285 }
 286
 287 int iscsi_service(struct iscsi_context *iscsi, int revents)
 288 {
 289         if (revents & POLLERR) {
 290                 printf("iscsi_service: POLLERR, socket error\n");
 291                 iscsi->connect_cb(iscsi, ISCSI_STATUS_ERROR, NULL, iscsi->connect_data);
 292                 return -1;
 293         }
 294         if (revents & POLLHUP) {
 295                 printf("iscsi_service: POLLHUP, socket error\n");
 296                 iscsi->connect_cb(iscsi, ISCSI_STATUS_ERROR, NULL, iscsi->connect_data);
 297                 return -2;
 298         }
 299
 300         if (iscsi->is_connected == 0 && iscsi->fd != -1 && revents&POLLOUT) {
 301                 iscsi->is_connected = 1;
 302                 iscsi->connect_cb(iscsi, ISCSI_STATUS_GOOD, NULL, iscsi->connect_data);
 303                 return 0;
 304         }
 305
 306         if (revents & POLLOUT && iscsi->outqueue != NULL) {
 307                 if (iscsi_write_to_socket(iscsi) != 0) {
 308                         printf("write to socket failed\n");
 309                         return -3;
 310                 }
 311         }
 312         if (revents & POLLIN) {
 313                 if (iscsi_read_from_socket(iscsi) != 0) {
 314                         printf("read from socket failed\n");
 315                         return -4;
 316                 }
 317         }
 318
 319         return 0;
 320 }
 321
 322 int iscsi_queue_pdu(struct iscsi_context *iscsi, struct iscsi_pdu *pdu)
 323 {
 324         if (iscsi == NULL) {
 325                 printf("trying to queue to NULL context\n");
 326                 return -1;
 327         }
 328         if (pdu == NULL) {
 329                 printf("trying to queue NULL pdu\n");
 330                 return -2;
 331         }
 332         DLIST_ADD_END(iscsi->outqueue, pdu, NULL);
 333
 334         return 0;
 335 }
 336
 337
 338