git.ozlabs.org Git - ccan/blob - ccan/iscsi/discovery.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 #define _GNU_SOURCE
  19 #include <stdio.h>
  20 #include <stdlib.h>
  21 #include <string.h>
  22 #include <arpa/inet.h>
  23 #include "iscsi.h"
  24 #include "iscsi-private.h"
  25
  26 int iscsi_discovery_async(struct iscsi_context *iscsi, iscsi_command_cb cb, void *private_data)
  27 {
  28         struct iscsi_pdu *pdu;
  29         char *str;
  30
  31         if (iscsi == NULL) {
  32                 printf("trying to send text on NULL context\n");
  33                 return -1;
  34         }
  35
  36         if (iscsi->session_type != ISCSI_SESSION_DISCOVERY) {
  37                 printf("Trying to do discovery on non-discovery session\n");
  38                 return -2;
  39         }
  40
  41         pdu = iscsi_allocate_pdu(iscsi, ISCSI_PDU_TEXT_REQUEST, ISCSI_PDU_TEXT_RESPONSE);
  42         if (pdu == NULL) {
  43                 printf("Failed to allocate text pdu\n");
  44                 return -3;
  45         }
  46
  47         /* immediate */
  48         iscsi_pdu_set_immediate(pdu);
  49
  50         /* flags */
  51         iscsi_pdu_set_pduflags(pdu, ISCSI_PDU_TEXT_FINAL);
  52
  53         /* target transfer tag */
  54         iscsi_pdu_set_ttt(pdu, 0xffffffff);
  55
  56         /* sendtargets */
  57         str = "SendTargets=All";
  58         if (iscsi_pdu_add_data(iscsi, pdu, (unsigned char *)str, strlen(str)+1) != 0) {
  59                 printf("pdu add data failed\n");
  60                 iscsi_free_pdu(iscsi, pdu);
  61                 return -4;
  62         }
  63
  64         pdu->callback     = cb;
  65         pdu->private_data = private_data;
  66
  67         if (iscsi_queue_pdu(iscsi, pdu) != 0) {
  68                 printf("failed to queue iscsi text pdu\n");
  69                 iscsi_free_pdu(iscsi, pdu);
  70                 return -5;
  71         }
  72
  73         return 0;
  74 }
  75
  76 static void iscsi_free_discovery_addresses(struct iscsi_discovery_address *addresses)
  77 {
  78         while (addresses != NULL) {
  79                 struct iscsi_discovery_address *next = addresses->next;
  80
  81                 if (addresses->target_name != NULL) {
  82                         free(discard_const(addresses->target_name));
  83                         addresses->target_name = NULL;
  84                 }
  85                 if (addresses->target_address != NULL) {
  86                         free(discard_const(addresses->target_address));
  87                         addresses->target_address = NULL;
  88                 }
  89                 addresses->next = NULL;
  90                 free(addresses);
  91                 addresses = next;
  92         }
  93 }
  94
  95 int iscsi_process_text_reply(struct iscsi_context *iscsi, struct iscsi_pdu *pdu, const unsigned char *hdr, int size)
  96 {
  97         struct iscsi_discovery_address *targets = NULL;
  98
  99         /* verify the response looks sane */
 100         if (hdr[1] != ISCSI_PDU_TEXT_FINAL) {
 101                 printf("unsupported flags in text reply %02x\n", hdr[1]);
 102                 pdu->callback(iscsi, ISCSI_STATUS_ERROR, NULL, pdu->private_data);
 103                 return -1;
 104         }
 105
 106         /* skip past the header */
 107         hdr  += ISCSI_HEADER_SIZE;
 108         size -= ISCSI_HEADER_SIZE;
 109
 110         while (size > 0) {
 111                 int len;
 112
 113                 len = strlen((char *)hdr);
 114
 115                 if (len == 0) {
 116                         break;
 117                 }
 118
 119                 if (len > size) {
 120                         printf("len > size when parsing discovery data %d>%d\n", len, size);
 121                         pdu->callback(iscsi, ISCSI_STATUS_ERROR, NULL, pdu->private_data);
 122                         iscsi_free_discovery_addresses(targets);
 123                         return -1;
 124                 }
 125
 126                 /* parse the strings */
 127                 if (!strncmp((char *)hdr, "TargetName=", 11)) {
 128                         struct iscsi_discovery_address *target;
 129
 130                         target = malloc(sizeof(struct iscsi_discovery_address));
 131                         if (target == NULL) {
 132                                 printf("Failed to allocate data for new discovered target\n");
 133                                 pdu->callback(iscsi, ISCSI_STATUS_ERROR, NULL, pdu->private_data);
 134                                 iscsi_free_discovery_addresses(targets);
 135                                 return -1;
 136                         }
 137                         bzero(target, sizeof(struct iscsi_discovery_address));
 138                         target->target_name = strdup((char *)hdr+11);
 139                         if (target->target_name == NULL) {
 140                                 printf("Failed to allocate data for new discovered target name\n");
 141                                 pdu->callback(iscsi, ISCSI_STATUS_ERROR, NULL, pdu->private_data);
 142                                 free(target);
 143                                 target = NULL;
 144                                 iscsi_free_discovery_addresses(targets);
 145                                 return -1;
 146                         }
 147                         target->next = targets;
 148                         targets = target;
 149                 } else if (!strncmp((char *)hdr, "TargetAddress=", 14)) {
 150                         targets->target_address = strdup((char *)hdr+14);
 151                         if (targets->target_address == NULL) {
 152                                 printf("Failed to allocate data for new discovered target address\n");
 153                                 pdu->callback(iscsi, ISCSI_STATUS_ERROR, NULL, pdu->private_data);
 154                                 iscsi_free_discovery_addresses(targets);
 155                                 return -1;
 156                         }
 157                 } else {
 158                         printf("Don't know how to handle discovery string : %s\n", hdr);
 159                         pdu->callback(iscsi, ISCSI_STATUS_ERROR, NULL, pdu->private_data);
 160                         iscsi_free_discovery_addresses(targets);
 161                         return -1;
 162                 }
 163
 164                 hdr  += len + 1;
 165                 size -= len + 1;
 166         }
 167
 168         pdu->callback(iscsi, ISCSI_STATUS_GOOD, targets, pdu->private_data);
 169         iscsi_free_discovery_addresses(targets);
 170
 171         return 0;
 172 }