usr.sbin/iscsid/discovery.c

   1 /*-
   2  * Copyright (c) 2012 The FreeBSD Foundation
   3  * All rights reserved.
   4  *
   5  * This software was developed by Edward Tomasz Napierala under sponsorship
   6  * from the FreeBSD Foundation.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  */
  30
  31 #include <sys/cdefs.h>
  32 __FBSDID("$FreeBSD$");
  33
  34 #include <sys/types.h>
  35 #include <sys/ioctl.h>
  36 #include <stdbool.h>
  37 #include <string.h>
  38 #include <netinet/in.h>
  39
  40 #include "iscsid.h"
  41 #include "iscsi_proto.h"
  42
  43 static struct pdu *
  44 text_receive(struct connection *conn)
  45 {
  46         struct pdu *response;
  47         struct iscsi_bhs_text_response *bhstr;
  48
  49         response = pdu_new(conn);
  50         pdu_receive(response);
  51         if (response->pdu_bhs->bhs_opcode != ISCSI_BHS_OPCODE_TEXT_RESPONSE)
  52                 log_errx(1, "protocol error: received invalid opcode 0x%x",
  53                     response->pdu_bhs->bhs_opcode);
  54         bhstr = (struct iscsi_bhs_text_response *)response->pdu_bhs;
  55 #if 0
  56         if ((bhstr->bhstr_flags & BHSTR_FLAGS_FINAL) == 0)
  57                 log_errx(1, "received Text PDU without the \"F\" flag");
  58 #endif
  59         /*
  60          * XXX: Implement the C flag some day.
  61          */
  62         if ((bhstr->bhstr_flags & BHSTR_FLAGS_CONTINUE) != 0)
  63                 log_errx(1, "received Text PDU with unsupported \"C\" flag");
  64         if (ntohl(bhstr->bhstr_statsn) != conn->conn_statsn + 1) {
  65                 log_errx(1, "received Text PDU with wrong StatSN: "
  66                     "is %u, should be %u", ntohl(bhstr->bhstr_statsn),
  67                     conn->conn_statsn + 1);
  68         }
  69         conn->conn_statsn = ntohl(bhstr->bhstr_statsn);
  70
  71         return (response);
  72 }
  73
  74 static struct pdu *
  75 text_new_request(struct connection *conn)
  76 {
  77         struct pdu *request;
  78         struct iscsi_bhs_text_request *bhstr;
  79
  80         request = pdu_new(conn);
  81         bhstr = (struct iscsi_bhs_text_request *)request->pdu_bhs;
  82         bhstr->bhstr_opcode = ISCSI_BHS_OPCODE_TEXT_REQUEST |
  83             ISCSI_BHS_OPCODE_IMMEDIATE;
  84         bhstr->bhstr_flags = BHSTR_FLAGS_FINAL;
  85         bhstr->bhstr_initiator_task_tag = 0;
  86         bhstr->bhstr_target_transfer_tag = 0xffffffff;
  87
  88         bhstr->bhstr_initiator_task_tag = 0; /* XXX */
  89         bhstr->bhstr_cmdsn = 0; /* XXX */
  90         bhstr->bhstr_expstatsn = htonl(conn->conn_statsn + 1);
  91
  92         return (request);
  93 }
  94
  95 static struct pdu *
  96 logout_receive(struct connection *conn)
  97 {
  98         struct pdu *response;
  99         struct iscsi_bhs_logout_response *bhslr;
 100
 101         response = pdu_new(conn);
 102         pdu_receive(response);
 103         if (response->pdu_bhs->bhs_opcode != ISCSI_BHS_OPCODE_LOGOUT_RESPONSE)
 104                 log_errx(1, "protocol error: received invalid opcode 0x%x",
 105                     response->pdu_bhs->bhs_opcode);
 106         bhslr = (struct iscsi_bhs_logout_response *)response->pdu_bhs;
 107         if (ntohs(bhslr->bhslr_response) != BHSLR_RESPONSE_CLOSED_SUCCESSFULLY)
 108                 log_warnx("received Logout Response with reason %d",
 109                     ntohs(bhslr->bhslr_response));
 110         if (ntohl(bhslr->bhslr_statsn) != conn->conn_statsn + 1) {
 111                 log_errx(1, "received Logout PDU with wrong StatSN: "
 112                     "is %u, should be %u", ntohl(bhslr->bhslr_statsn),
 113                     conn->conn_statsn + 1);
 114         }
 115         conn->conn_statsn = ntohl(bhslr->bhslr_statsn);
 116
 117         return (response);
 118 }
 119
 120 static struct pdu *
 121 logout_new_request(struct connection *conn)
 122 {
 123         struct pdu *request;
 124         struct iscsi_bhs_logout_request *bhslr;
 125
 126         request = pdu_new(conn);
 127         bhslr = (struct iscsi_bhs_logout_request *)request->pdu_bhs;
 128         bhslr->bhslr_opcode = ISCSI_BHS_OPCODE_LOGOUT_REQUEST |
 129             ISCSI_BHS_OPCODE_IMMEDIATE;
 130         bhslr->bhslr_reason = BHSLR_REASON_CLOSE_SESSION;
 131         bhslr->bhslr_reason |= 0x80;
 132         bhslr->bhslr_initiator_task_tag = 0; /* XXX */
 133         bhslr->bhslr_cmdsn = 0; /* XXX */
 134         bhslr->bhslr_expstatsn = htonl(conn->conn_statsn + 1);
 135
 136         return (request);
 137 }
 138
 139 static void
 140 kernel_add(const struct connection *conn, const char *target)
 141 {
 142         struct iscsi_session_add isa;
 143         int error;
 144
 145         memset(&isa, 0, sizeof(isa));
 146         memcpy(&isa.isa_conf, &conn->conn_conf, sizeof(isa.isa_conf));
 147         strlcpy(isa.isa_conf.isc_target, target,
 148             sizeof(isa.isa_conf.isc_target));
 149         isa.isa_conf.isc_discovery = 0;
 150         error = ioctl(conn->conn_iscsi_fd, ISCSISADD, &isa);
 151         if (error != 0)
 152                 log_warn("failed to add %s: ISCSISADD", target);
 153 }
 154
 155 static void
 156 kernel_remove(const struct connection *conn)
 157 {
 158         struct iscsi_session_remove isr;
 159         int error;
 160
 161         memset(&isr, 0, sizeof(isr));
 162         isr.isr_session_id = conn->conn_session_id;
 163         error = ioctl(conn->conn_iscsi_fd, ISCSISREMOVE, &isr);
 164         if (error != 0)
 165                 log_warn("ISCSISREMOVE");
 166 }
 167
 168 void
 169 discovery(struct connection *conn)
 170 {
 171         struct pdu *request, *response;
 172         struct keys *request_keys, *response_keys;
 173         int i;
 174
 175         log_debugx("beginning discovery session");
 176         request = text_new_request(conn);
 177         request_keys = keys_new();
 178         keys_add(request_keys, "SendTargets", "All");
 179         keys_save(request_keys, request);
 180         keys_delete(request_keys);
 181         request_keys = NULL;
 182         pdu_send(request);
 183         pdu_delete(request);
 184         request = NULL;
 185
 186         log_debugx("waiting for Text Response");
 187         response = text_receive(conn);
 188         response_keys = keys_new();
 189         keys_load(response_keys, response);
 190         for (i = 0; i < KEYS_MAX; i++) {
 191                 if (response_keys->keys_names[i] == NULL)
 192                         break;
 193
 194                 if (strcmp(response_keys->keys_names[i], "TargetName") != 0)
 195                         continue;
 196
 197                 log_debugx("adding target %s", response_keys->keys_values[i]);
 198                 /*
 199                  * XXX: Validate the target name?
 200                  */
 201                 kernel_add(conn, response_keys->keys_values[i]);
 202         }
 203         keys_delete(response_keys);
 204         pdu_delete(response);
 205
 206         log_debugx("removing temporary discovery session");
 207         kernel_remove(conn);
 208
 209 #ifdef ICL_KERNEL_PROXY
 210         if (conn->conn_conf.isc_iser == 1) {
 211                 /*
 212                  * If we're going through the proxy, the kernel already
 213                  * sent Logout PDU for us and destroyed the session,
 214                  * so we can't send anything anymore.
 215                  */
 216                 log_debugx("discovery session done");
 217                 return;
 218         }
 219 #endif
 220
 221         log_debugx("discovery done; logging out");
 222         request = logout_new_request(conn);
 223         pdu_send(request);
 224         pdu_delete(request);
 225         request = NULL;
 226
 227         log_debugx("waiting for Logout Response");
 228         response = logout_receive(conn);
 229         pdu_delete(response);
 230
 231         log_debugx("discovery session done");
 232 }