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