usr.sbin/ctld/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  * $FreeBSD$
  30  */
  31
  32 #include <assert.h>
  33 #include <stdint.h>
  34 #include <stdio.h>
  35 #include <stdlib.h>
  36 #include <string.h>
  37 #include <netinet/in.h>
  38
  39 #include "ctld.h"
  40 #include "iscsi_proto.h"
  41
  42 static struct pdu *
  43 text_receive(struct connection *conn)
  44 {
  45         struct pdu *request;
  46         struct iscsi_bhs_text_request *bhstr;
  47
  48         request = pdu_new(conn);
  49         pdu_receive(request);
  50         if ((request->pdu_bhs->bhs_opcode & ~ISCSI_BHS_OPCODE_IMMEDIATE) !=
  51             ISCSI_BHS_OPCODE_TEXT_REQUEST)
  52                 log_errx(1, "protocol error: received invalid opcode 0x%x",
  53                     request->pdu_bhs->bhs_opcode);
  54         bhstr = (struct iscsi_bhs_text_request *)request->pdu_bhs;
  55 #if 0
  56         if ((bhstr->bhstr_flags & ISCSI_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 (request->pdu_data_len == 0)
  65                 log_errx(1, "received Text PDU with empty data segment");
  66
  67         if (ntohl(bhstr->bhstr_cmdsn) < conn->conn_cmdsn) {
  68                 log_errx(1, "received Text PDU with decreasing CmdSN: "
  69                     "was %d, is %d", conn->conn_cmdsn, ntohl(bhstr->bhstr_cmdsn));
  70         }
  71         if (ntohl(bhstr->bhstr_expstatsn) != conn->conn_statsn) {
  72                 log_errx(1, "received Text PDU with wrong StatSN: "
  73                     "is %d, should be %d", ntohl(bhstr->bhstr_expstatsn),
  74                     conn->conn_statsn);
  75         }
  76         conn->conn_cmdsn = ntohl(bhstr->bhstr_cmdsn);
  77
  78         return (request);
  79 }
  80
  81 static struct pdu *
  82 text_new_response(struct pdu *request)
  83 {
  84         struct pdu *response;
  85         struct connection *conn;
  86         struct iscsi_bhs_text_request *bhstr;
  87         struct iscsi_bhs_text_response *bhstr2;
  88
  89         bhstr = (struct iscsi_bhs_text_request *)request->pdu_bhs;
  90         conn = request->pdu_connection;
  91
  92         response = pdu_new_response(request);
  93         bhstr2 = (struct iscsi_bhs_text_response *)response->pdu_bhs;
  94         bhstr2->bhstr_opcode = ISCSI_BHS_OPCODE_TEXT_RESPONSE;
  95         bhstr2->bhstr_flags = BHSTR_FLAGS_FINAL;
  96         bhstr2->bhstr_lun = bhstr->bhstr_lun;
  97         bhstr2->bhstr_initiator_task_tag = bhstr->bhstr_initiator_task_tag;
  98         bhstr2->bhstr_target_transfer_tag = bhstr->bhstr_target_transfer_tag;
  99         bhstr2->bhstr_statsn = htonl(conn->conn_statsn++);
 100         bhstr2->bhstr_expcmdsn = htonl(conn->conn_cmdsn);
 101         bhstr2->bhstr_maxcmdsn = htonl(conn->conn_cmdsn);
 102
 103         return (response);
 104 }
 105
 106 static struct pdu *
 107 logout_receive(struct connection *conn)
 108 {
 109         struct pdu *request;
 110         struct iscsi_bhs_logout_request *bhslr;
 111
 112         request = pdu_new(conn);
 113         pdu_receive(request);
 114         if ((request->pdu_bhs->bhs_opcode & ~ISCSI_BHS_OPCODE_IMMEDIATE) !=
 115             ISCSI_BHS_OPCODE_LOGOUT_REQUEST)
 116                 log_errx(1, "protocol error: received invalid opcode 0x%x",
 117                     request->pdu_bhs->bhs_opcode);
 118         bhslr = (struct iscsi_bhs_logout_request *)request->pdu_bhs;
 119         if ((bhslr->bhslr_reason & 0x7f) != BHSLR_REASON_CLOSE_SESSION)
 120                 log_debugx("received Logout PDU with invalid reason 0x%x; "
 121                     "continuing anyway", bhslr->bhslr_reason & 0x7f);
 122         if (ntohl(bhslr->bhslr_cmdsn) < conn->conn_cmdsn) {
 123                 log_errx(1, "received Logout PDU with decreasing CmdSN: "
 124                     "was %d, is %d", conn->conn_cmdsn,
 125                     ntohl(bhslr->bhslr_cmdsn));
 126         }
 127         if (ntohl(bhslr->bhslr_expstatsn) != conn->conn_statsn) {
 128                 log_errx(1, "received Logout PDU with wrong StatSN: "
 129                     "is %d, should be %d", ntohl(bhslr->bhslr_expstatsn),
 130                     conn->conn_statsn);
 131         }
 132         conn->conn_cmdsn = ntohl(bhslr->bhslr_cmdsn);
 133
 134         return (request);
 135 }
 136
 137 static struct pdu *
 138 logout_new_response(struct pdu *request)
 139 {
 140         struct pdu *response;
 141         struct connection *conn;
 142         struct iscsi_bhs_logout_request *bhslr;
 143         struct iscsi_bhs_logout_response *bhslr2;
 144
 145         bhslr = (struct iscsi_bhs_logout_request *)request->pdu_bhs;
 146         conn = request->pdu_connection;
 147
 148         response = pdu_new_response(request);
 149         bhslr2 = (struct iscsi_bhs_logout_response *)response->pdu_bhs;
 150         bhslr2->bhslr_opcode = ISCSI_BHS_OPCODE_LOGOUT_RESPONSE;
 151         bhslr2->bhslr_flags = 0x80;
 152         bhslr2->bhslr_response = BHSLR_RESPONSE_CLOSED_SUCCESSFULLY;
 153         bhslr2->bhslr_initiator_task_tag = bhslr->bhslr_initiator_task_tag;
 154         bhslr2->bhslr_statsn = htonl(conn->conn_statsn++);
 155         bhslr2->bhslr_expcmdsn = htonl(conn->conn_cmdsn);
 156         bhslr2->bhslr_maxcmdsn = htonl(conn->conn_cmdsn);
 157
 158         return (response);
 159 }
 160
 161 void
 162 discovery(struct connection *conn)
 163 {
 164         struct pdu *request, *response;
 165         struct keys *request_keys, *response_keys;
 166         struct target *targ;
 167         const char *send_targets;
 168
 169         log_debugx("beginning discovery session; waiting for Text PDU");
 170         request = text_receive(conn);
 171         request_keys = keys_new();
 172         keys_load(request_keys, request);
 173
 174         send_targets = keys_find(request_keys, "SendTargets");
 175         if (send_targets == NULL)
 176                 log_errx(1, "received Text PDU without SendTargets");
 177
 178         response = text_new_response(request);
 179         response_keys = keys_new();
 180
 181         if (strcmp(send_targets, "All") == 0) {
 182                 TAILQ_FOREACH(targ,
 183                     &conn->conn_portal->p_portal_group->pg_conf->conf_targets,
 184                     t_next) {
 185                         if (targ->t_portal_group !=
 186                             conn->conn_portal->p_portal_group) {
 187                                 log_debugx("not returning target \"%s\"; "
 188                                     "belongs to a different portal group",
 189                                     targ->t_iqn);
 190                                 continue;
 191                         }
 192                         keys_add(response_keys, "TargetName", targ->t_iqn);
 193                 }
 194         } else {
 195                 targ = target_find(conn->conn_portal->p_portal_group->pg_conf,
 196                     send_targets);
 197                 if (targ == NULL) {
 198                         log_debugx("initiator requested information on unknown "
 199                             "target \"%s\"; returning nothing", send_targets);
 200                 } else {
 201                         keys_add(response_keys, "TargetName", targ->t_iqn);
 202                 }
 203         }
 204         keys_save(response_keys, response);
 205
 206         pdu_send(response);
 207         pdu_delete(response);
 208         keys_delete(response_keys);
 209         pdu_delete(request);
 210         keys_delete(request_keys);
 211
 212         log_debugx("done sending targets; waiting for Logout PDU");
 213         request = logout_receive(conn);
 214         response = logout_new_response(request);
 215
 216         pdu_send(response);
 217         pdu_delete(response);
 218         pdu_delete(request);
 219
 220         log_debugx("discovery session done");
 221 }