xref: /freebsd/usr.sbin/ctld/discovery.cc (revision 66b5296f1b29083634e2875ff08c32e7b6b866a8)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2012 The FreeBSD Foundation
5  *
6  * This software was developed by Edward Tomasz Napierala under sponsorship
7  * from the FreeBSD Foundation.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  *
30  */
31 
32 #include <sys/cdefs.h>
33 #include <assert.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.hh"
42 #include "iscsi.hh"
43 #include "iscsi_proto.h"
44 
45 static struct pdu *
logout_receive(struct connection * conn)46 logout_receive(struct connection *conn)
47 {
48 	struct pdu *request;
49 	struct iscsi_bhs_logout_request *bhslr;
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_LOGOUT_REQUEST)
55 		log_errx(1, "protocol error: received invalid opcode 0x%x",
56 		    request->pdu_bhs->bhs_opcode);
57 	bhslr = (struct iscsi_bhs_logout_request *)request->pdu_bhs;
58 	if ((bhslr->bhslr_reason & 0x7f) != BHSLR_REASON_CLOSE_SESSION)
59 		log_debugx("received Logout PDU with invalid reason 0x%x; "
60 		    "continuing anyway", bhslr->bhslr_reason & 0x7f);
61 	if (ISCSI_SNLT(ntohl(bhslr->bhslr_cmdsn), conn->conn_cmdsn)) {
62 		log_errx(1, "received Logout PDU with decreasing CmdSN: "
63 		    "was %u, is %u", conn->conn_cmdsn,
64 		    ntohl(bhslr->bhslr_cmdsn));
65 	}
66 	if (ntohl(bhslr->bhslr_expstatsn) != conn->conn_statsn) {
67 		log_errx(1, "received Logout PDU with wrong ExpStatSN: "
68 		    "is %u, should be %u", ntohl(bhslr->bhslr_expstatsn),
69 		    conn->conn_statsn);
70 	}
71 	conn->conn_cmdsn = ntohl(bhslr->bhslr_cmdsn);
72 	if ((bhslr->bhslr_opcode & ISCSI_BHS_OPCODE_IMMEDIATE) == 0)
73 		conn->conn_cmdsn++;
74 
75 	return (request);
76 }
77 
78 static struct pdu *
logout_new_response(struct pdu * request)79 logout_new_response(struct pdu *request)
80 {
81 	struct pdu *response;
82 	struct connection *conn;
83 	struct iscsi_bhs_logout_request *bhslr;
84 	struct iscsi_bhs_logout_response *bhslr2;
85 
86 	bhslr = (struct iscsi_bhs_logout_request *)request->pdu_bhs;
87 	conn = request->pdu_connection;
88 
89 	response = pdu_new_response(request);
90 	bhslr2 = (struct iscsi_bhs_logout_response *)response->pdu_bhs;
91 	bhslr2->bhslr_opcode = ISCSI_BHS_OPCODE_LOGOUT_RESPONSE;
92 	bhslr2->bhslr_flags = 0x80;
93 	bhslr2->bhslr_response = BHSLR_RESPONSE_CLOSED_SUCCESSFULLY;
94 	bhslr2->bhslr_initiator_task_tag = bhslr->bhslr_initiator_task_tag;
95 	bhslr2->bhslr_statsn = htonl(conn->conn_statsn++);
96 	bhslr2->bhslr_expcmdsn = htonl(conn->conn_cmdsn);
97 	bhslr2->bhslr_maxcmdsn = htonl(conn->conn_cmdsn);
98 
99 	return (response);
100 }
101 
102 static void
discovery_add_target(struct keys * response_keys,const struct target * targ)103 discovery_add_target(struct keys *response_keys, const struct target *targ)
104 {
105 	char *buf;
106 	char hbuf[NI_MAXHOST], sbuf[NI_MAXSERV];
107 	const struct addrinfo *ai;
108 	int ret;
109 
110 	keys_add(response_keys, "TargetName", targ->name());
111 	for (const port *port : targ->ports()) {
112 	    const struct portal_group *pg = port->portal_group();
113 	    if (pg == nullptr)
114 		continue;
115 	    for (const portal_up &portal : pg->portals()) {
116 		if (portal->protocol() != portal_protocol::ISCSI &&
117 		    portal->protocol() != portal_protocol::ISER)
118 			continue;
119 		ai = portal->ai();
120 		ret = getnameinfo(ai->ai_addr, ai->ai_addrlen,
121 		    hbuf, sizeof(hbuf), sbuf, sizeof(sbuf),
122 		    NI_NUMERICHOST | NI_NUMERICSERV);
123 		if (ret != 0) {
124 			log_warnx("getnameinfo: %s", gai_strerror(ret));
125 			continue;
126 		}
127 		switch (ai->ai_addr->sa_family) {
128 		case AF_INET:
129 			if (strcmp(hbuf, "0.0.0.0") == 0)
130 				continue;
131 			ret = asprintf(&buf, "%s:%s,%d", hbuf, sbuf,
132 			    pg->tag());
133 			break;
134 		case AF_INET6:
135 			if (strcmp(hbuf, "::") == 0)
136 				continue;
137 			ret = asprintf(&buf, "[%s]:%s,%d", hbuf, sbuf,
138 			    pg->tag());
139 			break;
140 		default:
141 			continue;
142 		}
143 		if (ret <= 0)
144 		    log_err(1, "asprintf");
145 		keys_add(response_keys, "TargetAddress", buf);
146 		free(buf);
147 	    }
148 	}
149 }
150 
151 bool
discovery_target_filtered_out(const struct port * port) const152 iscsi_connection::discovery_target_filtered_out(const struct port *port) const
153 {
154 	const struct auth_group *ag;
155 	const struct portal_group *pg;
156 	const struct target *targ;
157 	const struct auth *auth;
158 	int error;
159 
160 	targ = port->target();
161 	ag = port->auth_group();
162 	if (ag == nullptr)
163 		ag = targ->auth_group();
164 	pg = conn_portal->portal_group();
165 
166 	assert(pg->discovery_filter() != discovery_filter::UNKNOWN);
167 
168 	if (pg->discovery_filter() >= discovery_filter::PORTAL &&
169 	    !ag->initiator_permitted(conn_initiator_sa)) {
170 		log_debugx("initiator does not match initiator portals "
171 		    "allowed for target \"%s\"; skipping", targ->name());
172 		return (true);
173 	}
174 
175 	if (pg->discovery_filter() >= discovery_filter::PORTAL_NAME &&
176 	    !ag->initiator_permitted(conn_initiator_name)) {
177 		log_debugx("initiator does not match initiator names "
178 		    "allowed for target \"%s\"; skipping", targ->name());
179 		return (true);
180 	}
181 
182 	if (pg->discovery_filter() >= discovery_filter::PORTAL_NAME_AUTH &&
183 	    ag->type() != auth_type::NO_AUTHENTICATION) {
184 		if (conn_chap == nullptr) {
185 			assert(pg->discovery_auth_group()->type() ==
186 			    auth_type::NO_AUTHENTICATION);
187 
188 			log_debugx("initiator didn't authenticate, but target "
189 			    "\"%s\" requires CHAP; skipping", targ->name());
190 			return (true);
191 		}
192 
193 		assert(!conn_user.empty());
194 		auth = ag->find_auth(conn_user);
195 		if (auth == NULL) {
196 			log_debugx("CHAP user \"%s\" doesn't match target "
197 			    "\"%s\"; skipping", conn_user.c_str(),
198 			    targ->name());
199 			return (true);
200 		}
201 
202 		error = chap_authenticate(conn_chap, auth->secret());
203 		if (error != 0) {
204 			log_debugx("password for CHAP user \"%s\" doesn't "
205 			    "match target \"%s\"; skipping",
206 			    conn_user.c_str(), targ->name());
207 			return (true);
208 		}
209 	}
210 
211 	return (false);
212 }
213 
214 void
discovery()215 iscsi_connection::discovery()
216 {
217 	struct pdu *request, *response;
218 	struct keys *request_keys, *response_keys;
219 	const struct port *port;
220 	const struct portal_group *pg;
221 	const char *send_targets;
222 
223 	pg = conn_portal->portal_group();
224 
225 	log_debugx("beginning discovery session; waiting for TextRequest PDU");
226 	request_keys = text_read_request(&conn, &request);
227 
228 	send_targets = keys_find(request_keys, "SendTargets");
229 	if (send_targets == NULL)
230 		log_errx(1, "received TextRequest PDU without SendTargets");
231 
232 	response_keys = keys_new();
233 
234 	if (strcmp(send_targets, "All") == 0) {
235 		for (const auto &kv : pg->ports()) {
236 			port = kv.second;
237 			if (discovery_target_filtered_out(port)) {
238 				/* Ignore this target. */
239 				continue;
240 			}
241 			discovery_add_target(response_keys, port->target());
242 		}
243 	} else {
244 		port = pg->find_port(send_targets);
245 		if (port == NULL) {
246 			log_debugx("initiator requested information on unknown "
247 			    "target \"%s\"; returning nothing", send_targets);
248 		} else {
249 			if (discovery_target_filtered_out(port)) {
250 				/* Ignore this target. */
251 			} else {
252 				discovery_add_target(response_keys,
253 				    port->target());
254 			}
255 		}
256 	}
257 
258 	text_send_response(request, response_keys);
259 	keys_delete(response_keys);
260 	pdu_delete(request);
261 	keys_delete(request_keys);
262 
263 	log_debugx("done sending targets; waiting for Logout PDU");
264 	request = logout_receive(&conn);
265 	response = logout_new_response(request);
266 
267 	pdu_send(response);
268 	pdu_delete(response);
269 	pdu_delete(request);
270 
271 	log_debugx("discovery session done");
272 }
273