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 <stdint.h>
  36 #include <stdio.h>
  37 #include <stdlib.h>
  38 #include <string.h>
  39 #include <netinet/in.h>
  40 #include <netdb.h>
  41 #include <sys/socket.h>
  42
  43 #include "ctld.h"
  44 #include "iscsi_proto.h"
  45
  46 static struct pdu *
  47 text_receive(struct connection *conn)
  48 {
  49         struct pdu *request;
  50         struct iscsi_bhs_text_request *bhstr;
  51
  52         request = pdu_new(conn);
  53         pdu_receive(request);
  54         if ((request->pdu_bhs->bhs_opcode & ~ISCSI_BHS_OPCODE_IMMEDIATE) !=
  55             ISCSI_BHS_OPCODE_TEXT_REQUEST)
  56                 log_errx(1, "protocol error: received invalid opcode 0x%x",
  57                     request->pdu_bhs->bhs_opcode);
  58         bhstr = (struct iscsi_bhs_text_request *)request->pdu_bhs;
  59 #if 0
  60         if ((bhstr->bhstr_flags & ISCSI_BHSTR_FLAGS_FINAL) == 0)
  61                 log_errx(1, "received Text PDU without the \"F\" flag");
  62 #endif
  63         /*
  64          * XXX: Implement the C flag some day.
  65          */
  66         if ((bhstr->bhstr_flags & BHSTR_FLAGS_CONTINUE) != 0)
  67                 log_errx(1, "received Text PDU with unsupported \"C\" flag");
  68         if (ISCSI_SNLT(ntohl(bhstr->bhstr_cmdsn), conn->conn_cmdsn)) {
  69                 log_errx(1, "received Text PDU with decreasing CmdSN: "
  70                     "was %u, is %u", conn->conn_cmdsn, ntohl(bhstr->bhstr_cmdsn));
  71         }
  72         if (ntohl(bhstr->bhstr_expstatsn) != conn->conn_statsn) {
  73                 log_errx(1, "received Text PDU with wrong StatSN: "
  74                     "is %u, should be %u", ntohl(bhstr->bhstr_expstatsn),
  75                     conn->conn_statsn);
  76         }
  77         conn->conn_cmdsn = ntohl(bhstr->bhstr_cmdsn);
  78
  79         return (request);
  80 }
  81
  82 static struct pdu *
  83 text_new_response(struct pdu *request)
  84 {
  85         struct pdu *response;
  86         struct connection *conn;
  87         struct iscsi_bhs_text_request *bhstr;
  88         struct iscsi_bhs_text_response *bhstr2;
  89
  90         bhstr = (struct iscsi_bhs_text_request *)request->pdu_bhs;
  91         conn = request->pdu_connection;
  92
  93         response = pdu_new_response(request);
  94         bhstr2 = (struct iscsi_bhs_text_response *)response->pdu_bhs;
  95         bhstr2->bhstr_opcode = ISCSI_BHS_OPCODE_TEXT_RESPONSE;
  96         bhstr2->bhstr_flags = BHSTR_FLAGS_FINAL;
  97         bhstr2->bhstr_lun = bhstr->bhstr_lun;
  98         bhstr2->bhstr_initiator_task_tag = bhstr->bhstr_initiator_task_tag;
  99         bhstr2->bhstr_target_transfer_tag = bhstr->bhstr_target_transfer_tag;
 100         bhstr2->bhstr_statsn = htonl(conn->conn_statsn++);
 101         bhstr2->bhstr_expcmdsn = htonl(conn->conn_cmdsn);
 102         bhstr2->bhstr_maxcmdsn = htonl(conn->conn_cmdsn);
 103
 104         return (response);
 105 }
 106
 107 static struct pdu *
 108 logout_receive(struct connection *conn)
 109 {
 110         struct pdu *request;
 111         struct iscsi_bhs_logout_request *bhslr;
 112
 113         request = pdu_new(conn);
 114         pdu_receive(request);
 115         if ((request->pdu_bhs->bhs_opcode & ~ISCSI_BHS_OPCODE_IMMEDIATE) !=
 116             ISCSI_BHS_OPCODE_LOGOUT_REQUEST)
 117                 log_errx(1, "protocol error: received invalid opcode 0x%x",
 118                     request->pdu_bhs->bhs_opcode);
 119         bhslr = (struct iscsi_bhs_logout_request *)request->pdu_bhs;
 120         if ((bhslr->bhslr_reason & 0x7f) != BHSLR_REASON_CLOSE_SESSION)
 121                 log_debugx("received Logout PDU with invalid reason 0x%x; "
 122                     "continuing anyway", bhslr->bhslr_reason & 0x7f);
 123         if (ISCSI_SNLT(ntohl(bhslr->bhslr_cmdsn), conn->conn_cmdsn)) {
 124                 log_errx(1, "received Logout PDU with decreasing CmdSN: "
 125                     "was %u, is %u", conn->conn_cmdsn,
 126                     ntohl(bhslr->bhslr_cmdsn));
 127         }
 128         if (ntohl(bhslr->bhslr_expstatsn) != conn->conn_statsn) {
 129                 log_errx(1, "received Logout PDU with wrong StatSN: "
 130                     "is %u, should be %u", ntohl(bhslr->bhslr_expstatsn),
 131                     conn->conn_statsn);
 132         }
 133         conn->conn_cmdsn = ntohl(bhslr->bhslr_cmdsn);
 134
 135         return (request);
 136 }
 137
 138 static struct pdu *
 139 logout_new_response(struct pdu *request)
 140 {
 141         struct pdu *response;
 142         struct connection *conn;
 143         struct iscsi_bhs_logout_request *bhslr;
 144         struct iscsi_bhs_logout_response *bhslr2;
 145
 146         bhslr = (struct iscsi_bhs_logout_request *)request->pdu_bhs;
 147         conn = request->pdu_connection;
 148
 149         response = pdu_new_response(request);
 150         bhslr2 = (struct iscsi_bhs_logout_response *)response->pdu_bhs;
 151         bhslr2->bhslr_opcode = ISCSI_BHS_OPCODE_LOGOUT_RESPONSE;
 152         bhslr2->bhslr_flags = 0x80;
 153         bhslr2->bhslr_response = BHSLR_RESPONSE_CLOSED_SUCCESSFULLY;
 154         bhslr2->bhslr_initiator_task_tag = bhslr->bhslr_initiator_task_tag;
 155         bhslr2->bhslr_statsn = htonl(conn->conn_statsn++);
 156         bhslr2->bhslr_expcmdsn = htonl(conn->conn_cmdsn);
 157         bhslr2->bhslr_maxcmdsn = htonl(conn->conn_cmdsn);
 158
 159         return (response);
 160 }
 161
 162 static void
 163 discovery_add_target(struct keys *response_keys, const struct target *targ)
 164 {
 165         struct portal *portal;
 166         char *buf;
 167         char hbuf[NI_MAXHOST], sbuf[NI_MAXSERV];
 168         struct addrinfo *ai;
 169         int ret;
 170
 171         keys_add(response_keys, "TargetName", targ->t_name);
 172         TAILQ_FOREACH(portal, &targ->t_portal_group->pg_portals, p_next) {
 173                 ai = portal->p_ai;
 174                 ret = getnameinfo(ai->ai_addr, ai->ai_addrlen,
 175                     hbuf, sizeof(hbuf), sbuf, sizeof(sbuf),
 176                     NI_NUMERICHOST | NI_NUMERICSERV);
 177                 if (ret != 0) {
 178                         log_warnx("getnameinfo: %s", gai_strerror(ret));
 179                         continue;
 180                 }
 181                 switch (ai->ai_addr->sa_family) {
 182                 case AF_INET:
 183                         if (strcmp(hbuf, "0.0.0.0") == 0)
 184                                 continue;
 185                         ret = asprintf(&buf, "%s:%s,%d", hbuf, sbuf,
 186                             targ->t_portal_group->pg_tag);
 187                         break;
 188                 case AF_INET6:
 189                         if (strcmp(hbuf, "::") == 0)
 190                                 continue;
 191                         ret = asprintf(&buf, "[%s]:%s,%d", hbuf, sbuf,
 192                             targ->t_portal_group->pg_tag);
 193                         break;
 194                 default:
 195                         continue;
 196                 }
 197                 if (ret <= 0)
 198                     log_err(1, "asprintf");
 199                 keys_add(response_keys, "TargetAddress", buf);
 200                 free(buf);
 201         }
 202 }
 203
 204 static bool
 205 discovery_target_filtered_out(const struct connection *conn,
 206     const struct target *targ)
 207 {
 208         const struct auth_group *ag;
 209         const struct portal_group *pg;
 210         const struct auth *auth;
 211         int error;
 212
 213         ag = targ->t_auth_group;
 214         pg = conn->conn_portal->p_portal_group;
 215
 216         assert(pg->pg_discovery_auth_group != PG_FILTER_UNKNOWN);
 217
 218         if (pg->pg_discovery_filter >= PG_FILTER_PORTAL &&
 219             auth_portal_check(ag, &conn->conn_initiator_sa) != 0) {
 220                 log_debugx("initiator does not match initiator portals "
 221                     "allowed for target \"%s\"; skipping", targ->t_name);
 222                 return (true);
 223         }
 224
 225         if (pg->pg_discovery_filter >= PG_FILTER_PORTAL_NAME &&
 226             auth_name_check(ag, conn->conn_initiator_name) != 0) {
 227                 log_debugx("initiator does not match initiator names "
 228                     "allowed for target \"%s\"; skipping", targ->t_name);
 229                 return (true);
 230         }
 231
 232         if (pg->pg_discovery_filter >= PG_FILTER_PORTAL_NAME_AUTH &&
 233             ag->ag_type != AG_TYPE_NO_AUTHENTICATION) {
 234                 if (conn->conn_chap == NULL) {
 235                         assert(pg->pg_discovery_auth_group->ag_type ==
 236                             AG_TYPE_NO_AUTHENTICATION);
 237
 238                         log_debugx("initiator didn't authenticate, but target "
 239                             "\"%s\" requires CHAP; skipping", targ->t_name);
 240                         return (true);
 241                 }
 242
 243                 assert(conn->conn_user != NULL);
 244                 auth = auth_find(ag, conn->conn_user);
 245                 if (auth == NULL) {
 246                         log_debugx("CHAP user \"%s\" doesn't match target "
 247                             "\"%s\"; skipping", conn->conn_user, targ->t_name);
 248                         return (true);
 249                 }
 250
 251                 error = chap_authenticate(conn->conn_chap, auth->a_secret);
 252                 if (error != 0) {
 253                         log_debugx("password for CHAP user \"%s\" doesn't "
 254                             "match target \"%s\"; skipping",
 255                             conn->conn_user, targ->t_name);
 256                         return (true);
 257                 }
 258         }
 259
 260         return (false);
 261 }
 262
 263 void
 264 discovery(struct connection *conn)
 265 {
 266         struct pdu *request, *response;
 267         struct keys *request_keys, *response_keys;
 268         const struct portal_group *pg;
 269         const struct target *targ;
 270         const char *send_targets;
 271
 272         pg = conn->conn_portal->p_portal_group;
 273
 274         log_debugx("beginning discovery session; waiting for Text PDU");
 275         request = text_receive(conn);
 276         request_keys = keys_new();
 277         keys_load(request_keys, request);
 278
 279         send_targets = keys_find(request_keys, "SendTargets");
 280         if (send_targets == NULL)
 281                 log_errx(1, "received Text PDU without SendTargets");
 282
 283         response = text_new_response(request);
 284         response_keys = keys_new();
 285
 286         if (strcmp(send_targets, "All") == 0) {
 287                 TAILQ_FOREACH(targ, &pg->pg_conf->conf_targets, t_next) {
 288                         if (targ->t_portal_group != pg) {
 289                                 log_debugx("not returning target \"%s\"; "
 290                                     "belongs to a different portal group",
 291                                     targ->t_name);
 292                                 continue;
 293                         }
 294                         if (discovery_target_filtered_out(conn, targ)) {
 295                                 /* Ignore this target. */
 296                                 continue;
 297                         }
 298                         discovery_add_target(response_keys, targ);
 299                 }
 300         } else {
 301                 targ = target_find(pg->pg_conf, send_targets);
 302                 if (targ == NULL) {
 303                         log_debugx("initiator requested information on unknown "
 304                             "target \"%s\"; returning nothing", send_targets);
 305                 } else {
 306                         if (discovery_target_filtered_out(conn, targ)) {
 307                                 /* Ignore this target. */
 308                         } else {
 309                                 discovery_add_target(response_keys, targ);
 310                         }
 311                 }
 312         }
 313         keys_save(response_keys, response);
 314
 315         pdu_send(response);
 316         pdu_delete(response);
 317         keys_delete(response_keys);
 318         pdu_delete(request);
 319         keys_delete(request_keys);
 320
 321         log_debugx("done sending targets; waiting for Logout PDU");
 322         request = logout_receive(conn);
 323         response = logout_new_response(request);
 324
 325         pdu_send(response);
 326         pdu_delete(response);
 327         pdu_delete(request);
 328
 329         log_debugx("discovery session done");
 330 }