xref: /freebsd/usr.sbin/ctld/discovery.c (revision 4d846d260e2b9a3d4d0a701462568268cbfe7a5b)
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 __FBSDID("$FreeBSD$");
34 
35 #include <assert.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 logout_receive(struct connection *conn)
48 {
49 	struct pdu *request;
50 	struct iscsi_bhs_logout_request *bhslr;
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_LOGOUT_REQUEST)
56 		log_errx(1, "protocol error: received invalid opcode 0x%x",
57 		    request->pdu_bhs->bhs_opcode);
58 	bhslr = (struct iscsi_bhs_logout_request *)request->pdu_bhs;
59 	if ((bhslr->bhslr_reason & 0x7f) != BHSLR_REASON_CLOSE_SESSION)
60 		log_debugx("received Logout PDU with invalid reason 0x%x; "
61 		    "continuing anyway", bhslr->bhslr_reason & 0x7f);
62 	if (ISCSI_SNLT(ntohl(bhslr->bhslr_cmdsn), conn->conn_cmdsn)) {
63 		log_errx(1, "received Logout PDU with decreasing CmdSN: "
64 		    "was %u, is %u", conn->conn_cmdsn,
65 		    ntohl(bhslr->bhslr_cmdsn));
66 	}
67 	if (ntohl(bhslr->bhslr_expstatsn) != conn->conn_statsn) {
68 		log_errx(1, "received Logout PDU with wrong ExpStatSN: "
69 		    "is %u, should be %u", ntohl(bhslr->bhslr_expstatsn),
70 		    conn->conn_statsn);
71 	}
72 	conn->conn_cmdsn = ntohl(bhslr->bhslr_cmdsn);
73 	if ((bhslr->bhslr_opcode & ISCSI_BHS_OPCODE_IMMEDIATE) == 0)
74 		conn->conn_cmdsn++;
75 
76 	return (request);
77 }
78 
79 static struct pdu *
80 logout_new_response(struct pdu *request)
81 {
82 	struct pdu *response;
83 	struct connection *conn;
84 	struct iscsi_bhs_logout_request *bhslr;
85 	struct iscsi_bhs_logout_response *bhslr2;
86 
87 	bhslr = (struct iscsi_bhs_logout_request *)request->pdu_bhs;
88 	conn = request->pdu_connection;
89 
90 	response = pdu_new_response(request);
91 	bhslr2 = (struct iscsi_bhs_logout_response *)response->pdu_bhs;
92 	bhslr2->bhslr_opcode = ISCSI_BHS_OPCODE_LOGOUT_RESPONSE;
93 	bhslr2->bhslr_flags = 0x80;
94 	bhslr2->bhslr_response = BHSLR_RESPONSE_CLOSED_SUCCESSFULLY;
95 	bhslr2->bhslr_initiator_task_tag = bhslr->bhslr_initiator_task_tag;
96 	bhslr2->bhslr_statsn = htonl(conn->conn_statsn++);
97 	bhslr2->bhslr_expcmdsn = htonl(conn->conn_cmdsn);
98 	bhslr2->bhslr_maxcmdsn = htonl(conn->conn_cmdsn);
99 
100 	return (response);
101 }
102 
103 static void
104 discovery_add_target(struct keys *response_keys, const struct target *targ)
105 {
106 	struct port *port;
107 	struct portal *portal;
108 	char *buf;
109 	char hbuf[NI_MAXHOST], sbuf[NI_MAXSERV];
110 	struct addrinfo *ai;
111 	int ret;
112 
113 	keys_add(response_keys, "TargetName", targ->t_name);
114 	TAILQ_FOREACH(port, &targ->t_ports, p_ts) {
115 	    if (port->p_portal_group == NULL)
116 		continue;
117 	    TAILQ_FOREACH(portal, &port->p_portal_group->pg_portals, p_next) {
118 		ai = portal->p_ai;
119 		ret = getnameinfo(ai->ai_addr, ai->ai_addrlen,
120 		    hbuf, sizeof(hbuf), sbuf, sizeof(sbuf),
121 		    NI_NUMERICHOST | NI_NUMERICSERV);
122 		if (ret != 0) {
123 			log_warnx("getnameinfo: %s", gai_strerror(ret));
124 			continue;
125 		}
126 		switch (ai->ai_addr->sa_family) {
127 		case AF_INET:
128 			if (strcmp(hbuf, "0.0.0.0") == 0)
129 				continue;
130 			ret = asprintf(&buf, "%s:%s,%d", hbuf, sbuf,
131 			    port->p_portal_group->pg_tag);
132 			break;
133 		case AF_INET6:
134 			if (strcmp(hbuf, "::") == 0)
135 				continue;
136 			ret = asprintf(&buf, "[%s]:%s,%d", hbuf, sbuf,
137 			    port->p_portal_group->pg_tag);
138 			break;
139 		default:
140 			continue;
141 		}
142 		if (ret <= 0)
143 		    log_err(1, "asprintf");
144 		keys_add(response_keys, "TargetAddress", buf);
145 		free(buf);
146 	    }
147 	}
148 }
149 
150 static bool
151 discovery_target_filtered_out(const struct ctld_connection *conn,
152     const struct port *port)
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->p_target;
161 	ag = port->p_auth_group;
162 	if (ag == NULL)
163 		ag = targ->t_auth_group;
164 	pg = conn->conn_portal->p_portal_group;
165 
166 	assert(pg->pg_discovery_auth_group != PG_FILTER_UNKNOWN);
167 
168 	if (pg->pg_discovery_filter >= PG_FILTER_PORTAL &&
169 	    auth_portal_check(ag, &conn->conn_initiator_sa) != 0) {
170 		log_debugx("initiator does not match initiator portals "
171 		    "allowed for target \"%s\"; skipping", targ->t_name);
172 		return (true);
173 	}
174 
175 	if (pg->pg_discovery_filter >= PG_FILTER_PORTAL_NAME &&
176 	    auth_name_check(ag, conn->conn_initiator_name) != 0) {
177 		log_debugx("initiator does not match initiator names "
178 		    "allowed for target \"%s\"; skipping", targ->t_name);
179 		return (true);
180 	}
181 
182 	if (pg->pg_discovery_filter >= PG_FILTER_PORTAL_NAME_AUTH &&
183 	    ag->ag_type != AG_TYPE_NO_AUTHENTICATION) {
184 		if (conn->conn_chap == NULL) {
185 			assert(pg->pg_discovery_auth_group->ag_type ==
186 			    AG_TYPE_NO_AUTHENTICATION);
187 
188 			log_debugx("initiator didn't authenticate, but target "
189 			    "\"%s\" requires CHAP; skipping", targ->t_name);
190 			return (true);
191 		}
192 
193 		assert(conn->conn_user != NULL);
194 		auth = auth_find(ag, conn->conn_user);
195 		if (auth == NULL) {
196 			log_debugx("CHAP user \"%s\" doesn't match target "
197 			    "\"%s\"; skipping", conn->conn_user, targ->t_name);
198 			return (true);
199 		}
200 
201 		error = chap_authenticate(conn->conn_chap, auth->a_secret);
202 		if (error != 0) {
203 			log_debugx("password for CHAP user \"%s\" doesn't "
204 			    "match target \"%s\"; skipping",
205 			    conn->conn_user, targ->t_name);
206 			return (true);
207 		}
208 	}
209 
210 	return (false);
211 }
212 
213 void
214 discovery(struct ctld_connection *conn)
215 {
216 	struct pdu *request, *response;
217 	struct keys *request_keys, *response_keys;
218 	const struct port *port;
219 	const struct portal_group *pg;
220 	const char *send_targets;
221 
222 	pg = conn->conn_portal->p_portal_group;
223 
224 	log_debugx("beginning discovery session; waiting for TextRequest PDU");
225 	request_keys = text_read_request(&conn->conn, &request);
226 
227 	send_targets = keys_find(request_keys, "SendTargets");
228 	if (send_targets == NULL)
229 		log_errx(1, "received TextRequest PDU without SendTargets");
230 
231 	response_keys = keys_new();
232 
233 	if (strcmp(send_targets, "All") == 0) {
234 		TAILQ_FOREACH(port, &pg->pg_ports, p_pgs) {
235 			if (discovery_target_filtered_out(conn, port)) {
236 				/* Ignore this target. */
237 				continue;
238 			}
239 			discovery_add_target(response_keys, port->p_target);
240 		}
241 	} else {
242 		port = port_find_in_pg(pg, send_targets);
243 		if (port == NULL) {
244 			log_debugx("initiator requested information on unknown "
245 			    "target \"%s\"; returning nothing", send_targets);
246 		} else {
247 			if (discovery_target_filtered_out(conn, port)) {
248 				/* Ignore this target. */
249 			} else {
250 				discovery_add_target(response_keys, port->p_target);
251 			}
252 		}
253 	}
254 
255 	text_send_response(request, response_keys);
256 	keys_delete(response_keys);
257 	pdu_delete(request);
258 	keys_delete(request_keys);
259 
260 	log_debugx("done sending targets; waiting for Logout PDU");
261 	request = logout_receive(&conn->conn);
262 	response = logout_new_response(request);
263 
264 	pdu_send(response);
265 	pdu_delete(response);
266 	pdu_delete(request);
267 
268 	log_debugx("discovery session done");
269 }
270