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  */
  30
  31 #include <sys/cdefs.h>
  32 __FBSDID("$FreeBSD$");
  33
  34 #include <assert.h>
  35 #include <stdio.h>
  36 #include <stdlib.h>
  37 #include <string.h>
  38 #include <netinet/in.h>
  39 #include <netdb.h>
  40 #include <sys/socket.h>
  41
  42 #include "ctld.h"
  43 #include "iscsi_proto.h"
  44
  45 static struct pdu *
  46 text_receive(struct connection *conn)
  47 {
  48         struct pdu *request;
  49         struct iscsi_bhs_text_request *bhstr;
  50
  51         request = pdu_new(conn);
  52         pdu_receive(request);
  53         if ((request->pdu_bhs->bhs_opcode & ~ISCSI_BHS_OPCODE_IMMEDIATE) !=
  54             ISCSI_BHS_OPCODE_TEXT_REQUEST)
  55                 log_errx(1, "protocol error: received invalid opcode 0x%x",
  56                     request->pdu_bhs->bhs_opcode);
  57         bhstr = (struct iscsi_bhs_text_request *)request->pdu_bhs;
  58 #if 0
  59         if ((bhstr->bhstr_flags & ISCSI_BHSTR_FLAGS_FINAL) == 0)
  60                 log_errx(1, "received Text PDU without the \"F\" flag");
  61 #endif
  62         /*
  63          * XXX: Implement the C flag some day.
  64          */
  65         if ((bhstr->bhstr_flags & BHSTR_FLAGS_CONTINUE) != 0)
  66                 log_errx(1, "received Text PDU with unsupported \"C\" flag");
  67         if (ISCSI_SNLT(ntohl(bhstr->bhstr_cmdsn), conn->conn_cmdsn)) {
  68                 log_errx(1, "received Text PDU with decreasing CmdSN: "
  69                     "was %u, is %u", 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 %u, should be %u", ntohl(bhstr->bhstr_expstatsn),
  74                     conn->conn_statsn);
  75         }
  76         conn->conn_cmdsn = ntohl(bhstr->bhstr_cmdsn);
  77         if ((bhstr->bhstr_opcode & ISCSI_BHS_OPCODE_IMMEDIATE) == 0)
  78                 conn->conn_cmdsn++;
  79
  80         return (request);
  81 }
  82
  83 static struct pdu *
  84 text_new_response(struct pdu *request)
  85 {
  86         struct pdu *response;
  87         struct connection *conn;
  88         struct iscsi_bhs_text_request *bhstr;
  89         struct iscsi_bhs_text_response *bhstr2;
  90
  91         bhstr = (struct iscsi_bhs_text_request *)request->pdu_bhs;
  92         conn = request->pdu_connection;
  93
  94         response = pdu_new_response(request);
  95         bhstr2 = (struct iscsi_bhs_text_response *)response->pdu_bhs;
  96         bhstr2->bhstr_opcode = ISCSI_BHS_OPCODE_TEXT_RESPONSE;
  97         bhstr2->bhstr_flags = BHSTR_FLAGS_FINAL;
  98         bhstr2->bhstr_lun = bhstr->bhstr_lun;
  99         bhstr2->bhstr_initiator_task_tag = bhstr->bhstr_initiator_task_tag;
 100         bhstr2->bhstr_target_transfer_tag = bhstr->bhstr_target_transfer_tag;
 101         bhstr2->bhstr_statsn = htonl(conn->conn_statsn++);
 102         bhstr2->bhstr_expcmdsn = htonl(conn->conn_cmdsn);
 103         bhstr2->bhstr_maxcmdsn = htonl(conn->conn_cmdsn);
 104
 105         return (response);
 106 }
 107
 108 static struct pdu *
 109 logout_receive(struct connection *conn)
 110 {
 111         struct pdu *request;
 112         struct iscsi_bhs_logout_request *bhslr;
 113
 114         request = pdu_new(conn);
 115         pdu_receive(request);
 116         if ((request->pdu_bhs->bhs_opcode & ~ISCSI_BHS_OPCODE_IMMEDIATE) !=
 117             ISCSI_BHS_OPCODE_LOGOUT_REQUEST)
 118                 log_errx(1, "protocol error: received invalid opcode 0x%x",
 119                     request->pdu_bhs->bhs_opcode);
 120         bhslr = (struct iscsi_bhs_logout_request *)request->pdu_bhs;
 121         if ((bhslr->bhslr_reason & 0x7f) != BHSLR_REASON_CLOSE_SESSION)
 122                 log_debugx("received Logout PDU with invalid reason 0x%x; "
 123                     "continuing anyway", bhslr->bhslr_reason & 0x7f);
 124         if (ISCSI_SNLT(ntohl(bhslr->bhslr_cmdsn), conn->conn_cmdsn)) {
 125                 log_errx(1, "received Logout PDU with decreasing CmdSN: "
 126                     "was %u, is %u", conn->conn_cmdsn,
 127                     ntohl(bhslr->bhslr_cmdsn));
 128         }
 129         if (ntohl(bhslr->bhslr_expstatsn) != conn->conn_statsn) {
 130                 log_errx(1, "received Logout PDU with wrong StatSN: "
 131                     "is %u, should be %u", ntohl(bhslr->bhslr_expstatsn),
 132                     conn->conn_statsn);
 133         }
 134         conn->conn_cmdsn = ntohl(bhslr->bhslr_cmdsn);
 135         if ((bhslr->bhslr_opcode & ISCSI_BHS_OPCODE_IMMEDIATE) == 0)
 136                 conn->conn_cmdsn++;
 137
 138         return (request);
 139 }
 140
 141 static struct pdu *
 142 logout_new_response(struct pdu *request)
 143 {
 144         struct pdu *response;
 145         struct connection *conn;
 146         struct iscsi_bhs_logout_request *bhslr;
 147         struct iscsi_bhs_logout_response *bhslr2;
 148
 149         bhslr = (struct iscsi_bhs_logout_request *)request->pdu_bhs;
 150         conn = request->pdu_connection;
 151
 152         response = pdu_new_response(request);
 153         bhslr2 = (struct iscsi_bhs_logout_response *)response->pdu_bhs;
 154         bhslr2->bhslr_opcode = ISCSI_BHS_OPCODE_LOGOUT_RESPONSE;
 155         bhslr2->bhslr_flags = 0x80;
 156         bhslr2->bhslr_response = BHSLR_RESPONSE_CLOSED_SUCCESSFULLY;
 157         bhslr2->bhslr_initiator_task_tag = bhslr->bhslr_initiator_task_tag;
 158         bhslr2->bhslr_statsn = htonl(conn->conn_statsn++);
 159         bhslr2->bhslr_expcmdsn = htonl(conn->conn_cmdsn);
 160         bhslr2->bhslr_maxcmdsn = htonl(conn->conn_cmdsn);
 161
 162         return (response);
 163 }
 164
 165 static void
 166 discovery_add_target(struct keys *response_keys, const struct target *targ)
 167 {
 168         struct port *port;
 169         struct portal *portal;
 170         char *buf;
 171         char hbuf[NI_MAXHOST], sbuf[NI_MAXSERV];
 172         struct addrinfo *ai;
 173         int ret;
 174
 175         keys_add(response_keys, "TargetName", targ->t_name);
 176         TAILQ_FOREACH(port, &targ->t_ports, p_ts) {
 177             if (port->p_portal_group == NULL)
 178                 continue;
 179             TAILQ_FOREACH(portal, &port->p_portal_group->pg_portals, p_next) {
 180                 ai = portal->p_ai;
 181                 ret = getnameinfo(ai->ai_addr, ai->ai_addrlen,
 182                     hbuf, sizeof(hbuf), sbuf, sizeof(sbuf),
 183                     NI_NUMERICHOST | NI_NUMERICSERV);
 184                 if (ret != 0) {
 185                         log_warnx("getnameinfo: %s", gai_strerror(ret));
 186                         continue;
 187                 }
 188                 switch (ai->ai_addr->sa_family) {
 189                 case AF_INET:
 190                         if (strcmp(hbuf, "0.0.0.0") == 0)
 191                                 continue;
 192                         ret = asprintf(&buf, "%s:%s,%d", hbuf, sbuf,
 193                             port->p_portal_group->pg_tag);
 194                         break;
 195                 case AF_INET6:
 196                         if (strcmp(hbuf, "::") == 0)
 197                                 continue;
 198                         ret = asprintf(&buf, "[%s]:%s,%d", hbuf, sbuf,
 199                             port->p_portal_group->pg_tag);
 200                         break;
 201                 default:
 202                         continue;
 203                 }
 204                 if (ret <= 0)
 205                     log_err(1, "asprintf");
 206                 keys_add(response_keys, "TargetAddress", buf);
 207                 free(buf);
 208             }
 209         }
 210 }
 211
 212 static bool
 213 discovery_target_filtered_out(const struct connection *conn,
 214     const struct port *port)
 215 {
 216         const struct auth_group *ag;
 217         const struct portal_group *pg;
 218         const struct target *targ;
 219         const struct auth *auth;
 220         int error;
 221
 222         targ = port->p_target;
 223         ag = port->p_auth_group;
 224         if (ag == NULL)
 225                 ag = targ->t_auth_group;
 226         pg = conn->conn_portal->p_portal_group;
 227
 228         assert(pg->pg_discovery_auth_group != PG_FILTER_UNKNOWN);
 229
 230         if (pg->pg_discovery_filter >= PG_FILTER_PORTAL &&
 231             auth_portal_check(ag, &conn->conn_initiator_sa) != 0) {
 232                 log_debugx("initiator does not match initiator portals "
 233                     "allowed for target \"%s\"; skipping", targ->t_name);
 234                 return (true);
 235         }
 236
 237         if (pg->pg_discovery_filter >= PG_FILTER_PORTAL_NAME &&
 238             auth_name_check(ag, conn->conn_initiator_name) != 0) {
 239                 log_debugx("initiator does not match initiator names "
 240                     "allowed for target \"%s\"; skipping", targ->t_name);
 241                 return (true);
 242         }
 243
 244         if (pg->pg_discovery_filter >= PG_FILTER_PORTAL_NAME_AUTH &&
 245             ag->ag_type != AG_TYPE_NO_AUTHENTICATION) {
 246                 if (conn->conn_chap == NULL) {
 247                         assert(pg->pg_discovery_auth_group->ag_type ==
 248                             AG_TYPE_NO_AUTHENTICATION);
 249
 250                         log_debugx("initiator didn't authenticate, but target "
 251                             "\"%s\" requires CHAP; skipping", targ->t_name);
 252                         return (true);
 253                 }
 254
 255                 assert(conn->conn_user != NULL);
 256                 auth = auth_find(ag, conn->conn_user);
 257                 if (auth == NULL) {
 258                         log_debugx("CHAP user \"%s\" doesn't match target "
 259                             "\"%s\"; skipping", conn->conn_user, targ->t_name);
 260                         return (true);
 261                 }
 262
 263                 error = chap_authenticate(conn->conn_chap, auth->a_secret);
 264                 if (error != 0) {
 265                         log_debugx("password for CHAP user \"%s\" doesn't "
 266                             "match target \"%s\"; skipping",
 267                             conn->conn_user, targ->t_name);
 268                         return (true);
 269                 }
 270         }
 271
 272         return (false);
 273 }
 274
 275 void
 276 discovery(struct connection *conn)
 277 {
 278         struct pdu *request, *response;
 279         struct keys *request_keys, *response_keys;
 280         const struct port *port;
 281         const struct portal_group *pg;
 282         const char *send_targets;
 283
 284         pg = conn->conn_portal->p_portal_group;
 285
 286         log_debugx("beginning discovery session; waiting for Text PDU");
 287         request = text_receive(conn);
 288         request_keys = keys_new();
 289         keys_load(request_keys, request);
 290
 291         send_targets = keys_find(request_keys, "SendTargets");
 292         if (send_targets == NULL)
 293                 log_errx(1, "received Text PDU without SendTargets");
 294
 295         response = text_new_response(request);
 296         response_keys = keys_new();
 297
 298         if (strcmp(send_targets, "All") == 0) {
 299                 TAILQ_FOREACH(port, &pg->pg_ports, p_pgs) {
 300                         if (discovery_target_filtered_out(conn, port)) {
 301                                 /* Ignore this target. */
 302                                 continue;
 303                         }
 304                         discovery_add_target(response_keys, port->p_target);
 305                 }
 306         } else {
 307                 port = port_find_in_pg(pg, send_targets);
 308                 if (port == NULL) {
 309                         log_debugx("initiator requested information on unknown "
 310                             "target \"%s\"; returning nothing", send_targets);
 311                 } else {
 312                         if (discovery_target_filtered_out(conn, port)) {
 313                                 /* Ignore this target. */
 314                         } else {
 315                                 discovery_add_target(response_keys, port->p_target);
 316                         }
 317                 }
 318         }
 319         keys_save(response_keys, response);
 320
 321         pdu_send(response);
 322         pdu_delete(response);
 323         keys_delete(response_keys);
 324         pdu_delete(request);
 325         keys_delete(request_keys);
 326
 327         log_debugx("done sending targets; waiting for Logout PDU");
 328         request = logout_receive(conn);
 329         response = logout_new_response(request);
 330
 331         pdu_send(response);
 332         pdu_delete(response);
 333         pdu_delete(request);
 334
 335         log_debugx("discovery session done");
 336 }