freebsd-dev/usr.sbin/iscsid/discovery.c
Edward Tomasz Napierala b7af91d012 When iscsid(8) is running in ICL proxy mode, don't try to send Logout PDUs.
The kernel already does this for us when we ask it to terminate the session.

MFC after:	1 month
Sponsored by:	The FreeBSD Foundation
2016-05-19 14:59:21 +00:00

233 lines
6.8 KiB
C

/*-
* Copyright (c) 2012 The FreeBSD Foundation
* All rights reserved.
*
* This software was developed by Edward Tomasz Napierala under sponsorship
* from the FreeBSD Foundation.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <sys/ioctl.h>
#include <stdbool.h>
#include <string.h>
#include <netinet/in.h>
#include "iscsid.h"
#include "iscsi_proto.h"
static struct pdu *
text_receive(struct connection *conn)
{
struct pdu *response;
struct iscsi_bhs_text_response *bhstr;
response = pdu_new(conn);
pdu_receive(response);
if (response->pdu_bhs->bhs_opcode != ISCSI_BHS_OPCODE_TEXT_RESPONSE)
log_errx(1, "protocol error: received invalid opcode 0x%x",
response->pdu_bhs->bhs_opcode);
bhstr = (struct iscsi_bhs_text_response *)response->pdu_bhs;
#if 0
if ((bhstr->bhstr_flags & BHSTR_FLAGS_FINAL) == 0)
log_errx(1, "received Text PDU without the \"F\" flag");
#endif
/*
* XXX: Implement the C flag some day.
*/
if ((bhstr->bhstr_flags & BHSTR_FLAGS_CONTINUE) != 0)
log_errx(1, "received Text PDU with unsupported \"C\" flag");
if (ntohl(bhstr->bhstr_statsn) != conn->conn_statsn + 1) {
log_errx(1, "received Text PDU with wrong StatSN: "
"is %u, should be %u", ntohl(bhstr->bhstr_statsn),
conn->conn_statsn + 1);
}
conn->conn_statsn = ntohl(bhstr->bhstr_statsn);
return (response);
}
static struct pdu *
text_new_request(struct connection *conn)
{
struct pdu *request;
struct iscsi_bhs_text_request *bhstr;
request = pdu_new(conn);
bhstr = (struct iscsi_bhs_text_request *)request->pdu_bhs;
bhstr->bhstr_opcode = ISCSI_BHS_OPCODE_TEXT_REQUEST |
ISCSI_BHS_OPCODE_IMMEDIATE;
bhstr->bhstr_flags = BHSTR_FLAGS_FINAL;
bhstr->bhstr_initiator_task_tag = 0;
bhstr->bhstr_target_transfer_tag = 0xffffffff;
bhstr->bhstr_initiator_task_tag = 0; /* XXX */
bhstr->bhstr_cmdsn = 0; /* XXX */
bhstr->bhstr_expstatsn = htonl(conn->conn_statsn + 1);
return (request);
}
static struct pdu *
logout_receive(struct connection *conn)
{
struct pdu *response;
struct iscsi_bhs_logout_response *bhslr;
response = pdu_new(conn);
pdu_receive(response);
if (response->pdu_bhs->bhs_opcode != ISCSI_BHS_OPCODE_LOGOUT_RESPONSE)
log_errx(1, "protocol error: received invalid opcode 0x%x",
response->pdu_bhs->bhs_opcode);
bhslr = (struct iscsi_bhs_logout_response *)response->pdu_bhs;
if (ntohs(bhslr->bhslr_response) != BHSLR_RESPONSE_CLOSED_SUCCESSFULLY)
log_warnx("received Logout Response with reason %d",
ntohs(bhslr->bhslr_response));
if (ntohl(bhslr->bhslr_statsn) != conn->conn_statsn + 1) {
log_errx(1, "received Logout PDU with wrong StatSN: "
"is %u, should be %u", ntohl(bhslr->bhslr_statsn),
conn->conn_statsn + 1);
}
conn->conn_statsn = ntohl(bhslr->bhslr_statsn);
return (response);
}
static struct pdu *
logout_new_request(struct connection *conn)
{
struct pdu *request;
struct iscsi_bhs_logout_request *bhslr;
request = pdu_new(conn);
bhslr = (struct iscsi_bhs_logout_request *)request->pdu_bhs;
bhslr->bhslr_opcode = ISCSI_BHS_OPCODE_LOGOUT_REQUEST |
ISCSI_BHS_OPCODE_IMMEDIATE;
bhslr->bhslr_reason = BHSLR_REASON_CLOSE_SESSION;
bhslr->bhslr_reason |= 0x80;
bhslr->bhslr_initiator_task_tag = 0; /* XXX */
bhslr->bhslr_cmdsn = 0; /* XXX */
bhslr->bhslr_expstatsn = htonl(conn->conn_statsn + 1);
return (request);
}
static void
kernel_add(const struct connection *conn, const char *target)
{
struct iscsi_session_add isa;
int error;
memset(&isa, 0, sizeof(isa));
memcpy(&isa.isa_conf, &conn->conn_conf, sizeof(isa.isa_conf));
strlcpy(isa.isa_conf.isc_target, target,
sizeof(isa.isa_conf.isc_target));
isa.isa_conf.isc_discovery = 0;
error = ioctl(conn->conn_iscsi_fd, ISCSISADD, &isa);
if (error != 0)
log_warn("failed to add %s: ISCSISADD", target);
}
static void
kernel_remove(const struct connection *conn)
{
struct iscsi_session_remove isr;
int error;
memset(&isr, 0, sizeof(isr));
isr.isr_session_id = conn->conn_session_id;
error = ioctl(conn->conn_iscsi_fd, ISCSISREMOVE, &isr);
if (error != 0)
log_warn("ISCSISREMOVE");
}
void
discovery(struct connection *conn)
{
struct pdu *request, *response;
struct keys *request_keys, *response_keys;
int i;
log_debugx("beginning discovery session");
request = text_new_request(conn);
request_keys = keys_new();
keys_add(request_keys, "SendTargets", "All");
keys_save(request_keys, request);
keys_delete(request_keys);
request_keys = NULL;
pdu_send(request);
pdu_delete(request);
request = NULL;
log_debugx("waiting for Text Response");
response = text_receive(conn);
response_keys = keys_new();
keys_load(response_keys, response);
for (i = 0; i < KEYS_MAX; i++) {
if (response_keys->keys_names[i] == NULL)
break;
if (strcmp(response_keys->keys_names[i], "TargetName") != 0)
continue;
log_debugx("adding target %s", response_keys->keys_values[i]);
/*
* XXX: Validate the target name?
*/
kernel_add(conn, response_keys->keys_values[i]);
}
keys_delete(response_keys);
pdu_delete(response);
log_debugx("removing temporary discovery session");
kernel_remove(conn);
#ifdef ICL_KERNEL_PROXY
if (conn->conn_conf.isc_iser == 1) {
/*
* If we're going through the proxy, the kernel already
* sent Logout PDU for us and destroyed the session,
* so we can't send anything anymore.
*/
log_debugx("discovery session done");
return;
}
#endif
log_debugx("discovery done; logging out");
request = logout_new_request(conn);
pdu_send(request);
pdu_delete(request);
request = NULL;
log_debugx("waiting for Logout Response");
response = logout_receive(conn);
pdu_delete(response);
log_debugx("discovery session done");
}