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 #include <netdb.h>
  39 #include <sys/socket.h>
  40
  41 #include "ctld.h"
  42 #include "iscsi_proto.h"
  43
  44 static struct pdu *
  45 text_receive(struct connection *conn)
  46 {
  47         struct pdu *request;
  48         struct iscsi_bhs_text_request *bhstr;
  49
  50         request = pdu_new(conn);
  51         pdu_receive(request);
  52         if ((request->pdu_bhs->bhs_opcode & ~ISCSI_BHS_OPCODE_IMMEDIATE) !=
  53             ISCSI_BHS_OPCODE_TEXT_REQUEST)
  54                 log_errx(1, "protocol error: received invalid opcode 0x%x",
  55                     request->pdu_bhs->bhs_opcode);
  56         bhstr = (struct iscsi_bhs_text_request *)request->pdu_bhs;
  57 #if 0
  58         if ((bhstr->bhstr_flags & ISCSI_BHSTR_FLAGS_FINAL) == 0)
  59                 log_errx(1, "received Text PDU without the \"F\" flag");
  60 #endif
  61         /*
  62          * XXX: Implement the C flag some day.
  63          */
  64         if ((bhstr->bhstr_flags & BHSTR_FLAGS_CONTINUE) != 0)
  65                 log_errx(1, "received Text PDU with unsupported \"C\" flag");
  66         if (ntohl(bhstr->bhstr_cmdsn) < conn->conn_cmdsn) {
  67                 log_errx(1, "received Text PDU with decreasing CmdSN: "
  68                     "was %d, is %d", conn->conn_cmdsn, ntohl(bhstr->bhstr_cmdsn));
  69         }
  70         if (ntohl(bhstr->bhstr_expstatsn) != conn->conn_statsn) {
  71                 log_errx(1, "received Text PDU with wrong StatSN: "
  72                     "is %d, should be %d", ntohl(bhstr->bhstr_expstatsn),
  73                     conn->conn_statsn);
  74         }
  75         conn->conn_cmdsn = ntohl(bhstr->bhstr_cmdsn);
  76
  77         return (request);
  78 }
  79
  80 static struct pdu *
  81 text_new_response(struct pdu *request)
  82 {
  83         struct pdu *response;
  84         struct connection *conn;
  85         struct iscsi_bhs_text_request *bhstr;
  86         struct iscsi_bhs_text_response *bhstr2;
  87
  88         bhstr = (struct iscsi_bhs_text_request *)request->pdu_bhs;
  89         conn = request->pdu_connection;
  90
  91         response = pdu_new_response(request);
  92         bhstr2 = (struct iscsi_bhs_text_response *)response->pdu_bhs;
  93         bhstr2->bhstr_opcode = ISCSI_BHS_OPCODE_TEXT_RESPONSE;
  94         bhstr2->bhstr_flags = BHSTR_FLAGS_FINAL;
  95         bhstr2->bhstr_lun = bhstr->bhstr_lun;
  96         bhstr2->bhstr_initiator_task_tag = bhstr->bhstr_initiator_task_tag;
  97         bhstr2->bhstr_target_transfer_tag = bhstr->bhstr_target_transfer_tag;
  98         bhstr2->bhstr_statsn = htonl(conn->conn_statsn++);
  99         bhstr2->bhstr_expcmdsn = htonl(conn->conn_cmdsn);
 100         bhstr2->bhstr_maxcmdsn = htonl(conn->conn_cmdsn);
 101
 102         return (response);
 103 }
 104
 105 static struct pdu *
 106 logout_receive(struct connection *conn)
 107 {
 108         struct pdu *request;
 109         struct iscsi_bhs_logout_request *bhslr;
 110
 111         request = pdu_new(conn);
 112         pdu_receive(request);
 113         if ((request->pdu_bhs->bhs_opcode & ~ISCSI_BHS_OPCODE_IMMEDIATE) !=
 114             ISCSI_BHS_OPCODE_LOGOUT_REQUEST)
 115                 log_errx(1, "protocol error: received invalid opcode 0x%x",
 116                     request->pdu_bhs->bhs_opcode);
 117         bhslr = (struct iscsi_bhs_logout_request *)request->pdu_bhs;
 118         if ((bhslr->bhslr_reason & 0x7f) != BHSLR_REASON_CLOSE_SESSION)
 119                 log_debugx("received Logout PDU with invalid reason 0x%x; "
 120                     "continuing anyway", bhslr->bhslr_reason & 0x7f);
 121         if (ntohl(bhslr->bhslr_cmdsn) < conn->conn_cmdsn) {
 122                 log_errx(1, "received Logout PDU with decreasing CmdSN: "
 123                     "was %d, is %d", conn->conn_cmdsn,
 124                     ntohl(bhslr->bhslr_cmdsn));
 125         }
 126         if (ntohl(bhslr->bhslr_expstatsn) != conn->conn_statsn) {
 127                 log_errx(1, "received Logout PDU with wrong StatSN: "
 128                     "is %d, should be %d", ntohl(bhslr->bhslr_expstatsn),
 129                     conn->conn_statsn);
 130         }
 131         conn->conn_cmdsn = ntohl(bhslr->bhslr_cmdsn);
 132
 133         return (request);
 134 }
 135
 136 static struct pdu *
 137 logout_new_response(struct pdu *request)
 138 {
 139         struct pdu *response;
 140         struct connection *conn;
 141         struct iscsi_bhs_logout_request *bhslr;
 142         struct iscsi_bhs_logout_response *bhslr2;
 143
 144         bhslr = (struct iscsi_bhs_logout_request *)request->pdu_bhs;
 145         conn = request->pdu_connection;
 146
 147         response = pdu_new_response(request);
 148         bhslr2 = (struct iscsi_bhs_logout_response *)response->pdu_bhs;
 149         bhslr2->bhslr_opcode = ISCSI_BHS_OPCODE_LOGOUT_RESPONSE;
 150         bhslr2->bhslr_flags = 0x80;
 151         bhslr2->bhslr_response = BHSLR_RESPONSE_CLOSED_SUCCESSFULLY;
 152         bhslr2->bhslr_initiator_task_tag = bhslr->bhslr_initiator_task_tag;
 153         bhslr2->bhslr_statsn = htonl(conn->conn_statsn++);
 154         bhslr2->bhslr_expcmdsn = htonl(conn->conn_cmdsn);
 155         bhslr2->bhslr_maxcmdsn = htonl(conn->conn_cmdsn);
 156
 157         return (response);
 158 }
 159
 160 static void
 161 discovery_add_target(struct keys *response_keys, struct target *targ)
 162 {
 163         struct portal *portal;
 164         char *buf;
 165         char hbuf[NI_MAXHOST], sbuf[NI_MAXSERV];
 166         struct addrinfo *ai;
 167         int ret;
 168
 169         keys_add(response_keys, "TargetName", targ->t_name);
 170         TAILQ_FOREACH(portal, &targ->t_portal_group->pg_portals, p_next) {
 171                 ai = portal->p_ai;
 172                 ret = getnameinfo(ai->ai_addr, ai->ai_addrlen,
 173                     hbuf, sizeof(hbuf), sbuf, sizeof(sbuf),
 174                     NI_NUMERICHOST | NI_NUMERICSERV);
 175                 if (ret != 0) {
 176                         log_warnx("getnameinfo: %s", gai_strerror(ret));
 177                         continue;
 178                 }
 179                 switch (ai->ai_addr->sa_family) {
 180                 case AF_INET:
 181                         if (strcmp(hbuf, "0.0.0.0") == 0)
 182                                 continue;
 183                         ret = asprintf(&buf, "%s:%s,%d", hbuf, sbuf,
 184                             targ->t_portal_group->pg_tag);
 185                         break;
 186                 case AF_INET6:
 187                         if (strcmp(hbuf, "::") == 0)
 188                                 continue;
 189                         ret = asprintf(&buf, "[%s]:%s,%d", hbuf, sbuf,
 190                             targ->t_portal_group->pg_tag);
 191                         break;
 192                 default:
 193                         continue;
 194                 }
 195                 if (ret <= 0)
 196                     log_err(1, "asprintf");
 197                 keys_add(response_keys, "TargetAddress", buf);
 198                 free(buf);
 199         }
 200 }
 201
 202 void
 203 discovery(struct connection *conn)
 204 {
 205         struct pdu *request, *response;
 206         struct keys *request_keys, *response_keys;
 207         struct target *targ;
 208         const char *send_targets;
 209
 210         log_debugx("beginning discovery session; waiting for Text PDU");
 211         request = text_receive(conn);
 212         request_keys = keys_new();
 213         keys_load(request_keys, request);
 214
 215         send_targets = keys_find(request_keys, "SendTargets");
 216         if (send_targets == NULL)
 217                 log_errx(1, "received Text PDU without SendTargets");
 218
 219         response = text_new_response(request);
 220         response_keys = keys_new();
 221
 222         if (strcmp(send_targets, "All") == 0) {
 223                 TAILQ_FOREACH(targ,
 224                     &conn->conn_portal->p_portal_group->pg_conf->conf_targets,
 225                     t_next) {
 226                         if (targ->t_portal_group !=
 227                             conn->conn_portal->p_portal_group) {
 228                                 log_debugx("not returning target \"%s\"; "
 229                                     "belongs to a different portal group",
 230                                     targ->t_name);
 231                                 continue;
 232                         }
 233                         discovery_add_target(response_keys, targ);
 234                 }
 235         } else {
 236                 targ = target_find(conn->conn_portal->p_portal_group->pg_conf,
 237                     send_targets);
 238                 if (targ == NULL) {
 239                         log_debugx("initiator requested information on unknown "
 240                             "target \"%s\"; returning nothing", send_targets);
 241                 } else
 242                         discovery_add_target(response_keys, targ);
 243         }
 244         keys_save(response_keys, response);
 245
 246         pdu_send(response);
 247         pdu_delete(response);
 248         keys_delete(response_keys);
 249         pdu_delete(request);
 250         keys_delete(request_keys);
 251
 252         log_debugx("done sending targets; waiting for Logout PDU");
 253         request = logout_receive(conn);
 254         response = logout_new_response(request);
 255
 256         pdu_send(response);
 257         pdu_delete(response);
 258         pdu_delete(request);
 259
 260         log_debugx("discovery session done");
 261 }