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/types.h>
33#include <sys/ioctl.h>
34#include <stdbool.h>
35#include <string.h>
36#include <netinet/in.h>
37
38#include "iscsid.h"
39#include "iscsi_proto.h"
40
41static struct pdu *
42logout_receive(struct connection *conn)
43{
44	struct pdu *response;
45	struct iscsi_bhs_logout_response *bhslr;
46
47	response = pdu_new(conn);
48	pdu_receive(response);
49	if (response->pdu_bhs->bhs_opcode != ISCSI_BHS_OPCODE_LOGOUT_RESPONSE)
50		log_errx(1, "protocol error: received invalid opcode 0x%x",
51		    response->pdu_bhs->bhs_opcode);
52	bhslr = (struct iscsi_bhs_logout_response *)response->pdu_bhs;
53	if (ntohs(bhslr->bhslr_response) != BHSLR_RESPONSE_CLOSED_SUCCESSFULLY)
54		log_warnx("received Logout Response with reason %d",
55		    ntohs(bhslr->bhslr_response));
56	if (ntohl(bhslr->bhslr_statsn) != conn->conn_statsn + 1) {
57		log_errx(1, "received Logout PDU with wrong StatSN: "
58		    "is %u, should be %u", ntohl(bhslr->bhslr_statsn),
59		    conn->conn_statsn + 1);
60	}
61	conn->conn_statsn = ntohl(bhslr->bhslr_statsn);
62
63	return (response);
64}
65
66static struct pdu *
67logout_new_request(struct connection *conn)
68{
69	struct pdu *request;
70	struct iscsi_bhs_logout_request *bhslr;
71
72	request = pdu_new(conn);
73	bhslr = (struct iscsi_bhs_logout_request *)request->pdu_bhs;
74	bhslr->bhslr_opcode = ISCSI_BHS_OPCODE_LOGOUT_REQUEST |
75	    ISCSI_BHS_OPCODE_IMMEDIATE;
76	bhslr->bhslr_reason = BHSLR_REASON_CLOSE_SESSION;
77	bhslr->bhslr_reason |= 0x80;
78	bhslr->bhslr_initiator_task_tag = 0; /* XXX */
79	bhslr->bhslr_cmdsn = 0; /* XXX */
80	bhslr->bhslr_expstatsn = htonl(conn->conn_statsn + 1);
81
82	return (request);
83}
84
85static void
86kernel_add(const struct iscsid_connection *conn, const char *target)
87{
88	struct iscsi_session_add isa;
89	int error;
90
91	memset(&isa, 0, sizeof(isa));
92	memcpy(&isa.isa_conf, &conn->conn_conf, sizeof(isa.isa_conf));
93	strlcpy(isa.isa_conf.isc_target, target,
94	    sizeof(isa.isa_conf.isc_target));
95	isa.isa_conf.isc_discovery = 0;
96	error = ioctl(conn->conn_iscsi_fd, ISCSISADD, &isa);
97	if (error != 0)
98		log_warn("failed to add %s: ISCSISADD", target);
99}
100
101static void
102kernel_remove(const struct iscsid_connection *conn)
103{
104	struct iscsi_session_remove isr;
105	int error;
106
107	memset(&isr, 0, sizeof(isr));
108	isr.isr_session_id = conn->conn_session_id;
109	error = ioctl(conn->conn_iscsi_fd, ISCSISREMOVE, &isr);
110	if (error != 0)
111		log_warn("ISCSISREMOVE");
112}
113
114void
115discovery(struct iscsid_connection *conn)
116{
117	struct pdu *request, *response;
118	struct keys *request_keys, *response_keys;
119	int i;
120
121	log_debugx("beginning discovery session");
122	request_keys = keys_new();
123	keys_add(request_keys, "SendTargets", "All");
124	text_send_request(&conn->conn, request_keys);
125	keys_delete(request_keys);
126	request_keys = NULL;
127
128	log_debugx("waiting for Text Response");
129	response_keys = text_read_response(&conn->conn);
130	for (i = 0; i < KEYS_MAX; i++) {
131		if (response_keys->keys_names[i] == NULL)
132			break;
133
134		if (strcmp(response_keys->keys_names[i], "TargetName") != 0)
135			continue;
136
137		log_debugx("adding target %s", response_keys->keys_values[i]);
138		/*
139		 * XXX: Validate the target name?
140		 */
141		kernel_add(conn, response_keys->keys_values[i]);
142	}
143	keys_delete(response_keys);
144
145	log_debugx("removing temporary discovery session");
146	kernel_remove(conn);
147
148#ifdef ICL_KERNEL_PROXY
149	if (conn->conn_conf.isc_iser == 1) {
150		/*
151		 * If we're going through the proxy, the kernel already
152		 * sent Logout PDU for us and destroyed the session,
153		 * so we can't send anything anymore.
154		 */
155		log_debugx("discovery session done");
156		return;
157	}
158#endif
159
160	log_debugx("discovery done; logging out");
161	request = logout_new_request(&conn->conn);
162	pdu_send(request);
163	pdu_delete(request);
164	request = NULL;
165
166	log_debugx("waiting for Logout Response");
167	response = logout_receive(&conn->conn);
168	pdu_delete(response);
169
170	log_debugx("discovery session done");
171}
172