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/*-
* 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 <assert.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <netinet/in.h>
#include "iscsid.h"
#include "iscsi_proto.h"
static int
login_nsg(const struct pdu *response)
{
struct iscsi_bhs_login_response *bhslr;
bhslr = (struct iscsi_bhs_login_response *)response->pdu_bhs;
return (bhslr->bhslr_flags & 0x03);
}
static void
login_set_nsg(struct pdu *request, int nsg)
{
struct iscsi_bhs_login_request *bhslr;
assert(nsg == BHSLR_STAGE_SECURITY_NEGOTIATION ||
nsg == BHSLR_STAGE_OPERATIONAL_NEGOTIATION ||
nsg == BHSLR_STAGE_FULL_FEATURE_PHASE);
bhslr = (struct iscsi_bhs_login_request *)request->pdu_bhs;
bhslr->bhslr_flags &= 0xFC;
bhslr->bhslr_flags |= nsg;
}
static void
login_set_csg(struct pdu *request, int csg)
{
struct iscsi_bhs_login_request *bhslr;
assert(csg == BHSLR_STAGE_SECURITY_NEGOTIATION ||
csg == BHSLR_STAGE_OPERATIONAL_NEGOTIATION ||
csg == BHSLR_STAGE_FULL_FEATURE_PHASE);
bhslr = (struct iscsi_bhs_login_request *)request->pdu_bhs;
bhslr->bhslr_flags &= 0xF3;
bhslr->bhslr_flags |= csg << 2;
}
static const char *
login_target_error_str(int class, int detail)
{
static char msg[128];
/*
* RFC 3270, 10.13.5. Status-Class and Status-Detail
*/
switch (class) {
case 0x01:
switch (detail) {
case 0x01:
return ("Target moved temporarily");
case 0x02:
return ("Target moved permanently");
default:
snprintf(msg, sizeof(msg), "unknown redirection; "
"Status-Class 0x%x, Status-Detail 0x%x",
class, detail);
return (msg);
}
case 0x02:
switch (detail) {
case 0x00:
return ("Initiator error");
case 0x01:
return ("Authentication failure");
case 0x02:
return ("Authorization failure");
case 0x03:
return ("Not found");
case 0x04:
return ("Target removed");
case 0x05:
return ("Unsupported version");
case 0x06:
return ("Too many connections");
case 0x07:
return ("Missing parameter");
case 0x08:
return ("Can't include in session");
case 0x09:
return ("Session type not supported");
case 0x0a:
return ("Session does not exist");
case 0x0b:
return ("Invalid during login");
default:
snprintf(msg, sizeof(msg), "unknown initiator error; "
"Status-Class 0x%x, Status-Detail 0x%x",
class, detail);
return (msg);
}
case 0x03:
switch (detail) {
case 0x00:
return ("Target error");
case 0x01:
return ("Service unavailable");
case 0x02:
return ("Out of resources");
default:
snprintf(msg, sizeof(msg), "unknown target error; "
"Status-Class 0x%x, Status-Detail 0x%x",
class, detail);
return (msg);
}
default:
snprintf(msg, sizeof(msg), "unknown error; "
"Status-Class 0x%x, Status-Detail 0x%x",
class, detail);
return (msg);
}
}
static void
kernel_modify(const struct connection *conn, const char *target_address)
{
struct iscsi_session_modify ism;
int error;
memset(&ism, 0, sizeof(ism));
ism.ism_session_id = conn->conn_session_id;
memcpy(&ism.ism_conf, &conn->conn_conf, sizeof(ism.ism_conf));
strlcpy(ism.ism_conf.isc_target_addr, target_address,
sizeof(ism.ism_conf.isc_target));
error = ioctl(conn->conn_iscsi_fd, ISCSISMODIFY, &ism);
if (error != 0) {
log_err(1, "failed to redirect to %s: ISCSISMODIFY",
target_address);
}
}
/*
* XXX: The way it works is suboptimal; what should happen is described
* in draft-gilligan-iscsi-fault-tolerance-00. That, however, would
* be much more complicated: we would need to keep "dependencies"
* for sessions, so that, in case described in draft and using draft
* terminology, we would have three sessions: one for discovery,
* one for initial target portal, and one for redirect portal.
* This would allow us to "backtrack" on connection failure,
* as described in draft.
*/
static void
login_handle_redirection(struct connection *conn, struct pdu *response)
{
struct iscsi_bhs_login_response *bhslr;
struct keys *response_keys;
const char *target_address;
bhslr = (struct iscsi_bhs_login_response *)response->pdu_bhs;
assert (bhslr->bhslr_status_class == 1);
response_keys = keys_new();
keys_load(response_keys, response);
target_address = keys_find(response_keys, "TargetAddress");
if (target_address == NULL)
log_errx(1, "received redirection without TargetAddress");
if (target_address[0] == '\0')
log_errx(1, "received redirection with empty TargetAddress");
if (strlen(target_address) >=
sizeof(conn->conn_conf.isc_target_addr) - 1)
log_errx(1, "received TargetAddress is too long");
log_debugx("received redirection to \"%s\"", target_address);
kernel_modify(conn, target_address);
keys_delete(response_keys);
}
static struct pdu *
login_receive(struct connection *conn)
{
struct pdu *response;
struct iscsi_bhs_login_response *bhslr;
const char *errorstr;
static bool initial = true;
response = pdu_new(conn);
pdu_receive(response);
if (response->pdu_bhs->bhs_opcode != ISCSI_BHS_OPCODE_LOGIN_RESPONSE) {
log_errx(1, "protocol error: received invalid opcode 0x%x",
response->pdu_bhs->bhs_opcode);
}
bhslr = (struct iscsi_bhs_login_response *)response->pdu_bhs;
/*
* XXX: Implement the C flag some day.
*/
if ((bhslr->bhslr_flags & BHSLR_FLAGS_CONTINUE) != 0)
log_errx(1, "received Login PDU with unsupported \"C\" flag");
if (bhslr->bhslr_version_max != 0x00)
log_errx(1, "received Login PDU with unsupported "
"Version-max 0x%x", bhslr->bhslr_version_max);
if (bhslr->bhslr_version_active != 0x00)
log_errx(1, "received Login PDU with unsupported "
"Version-active 0x%x", bhslr->bhslr_version_active);
if (bhslr->bhslr_status_class == 1) {
login_handle_redirection(conn, response);
log_debugx("redirection handled; exiting");
exit(0);
}
if (bhslr->bhslr_status_class != 0) {
errorstr = login_target_error_str(bhslr->bhslr_status_class,
bhslr->bhslr_status_detail);
fail(conn, errorstr);
log_errx(1, "target returned error: %s", errorstr);
}
if (initial == false &&
ntohl(bhslr->bhslr_statsn) != conn->conn_statsn + 1) {
/*
* It's a warning, not an error, to work around what seems
* to be bug in NetBSD iSCSI target.
*/
log_warnx("received Login PDU with wrong StatSN: "
"is %u, should be %u", ntohl(bhslr->bhslr_statsn),
conn->conn_statsn + 1);
}
conn->conn_tsih = ntohs(bhslr->bhslr_tsih);
conn->conn_statsn = ntohl(bhslr->bhslr_statsn);
initial = false;
return (response);
}
static struct pdu *
login_new_request(struct connection *conn, int csg)
{
struct pdu *request;
struct iscsi_bhs_login_request *bhslr;
int nsg;
request = pdu_new(conn);
bhslr = (struct iscsi_bhs_login_request *)request->pdu_bhs;
bhslr->bhslr_opcode = ISCSI_BHS_OPCODE_LOGIN_REQUEST |
ISCSI_BHS_OPCODE_IMMEDIATE;
bhslr->bhslr_flags = BHSLR_FLAGS_TRANSIT;
switch (csg) {
case BHSLR_STAGE_SECURITY_NEGOTIATION:
nsg = BHSLR_STAGE_OPERATIONAL_NEGOTIATION;
break;
case BHSLR_STAGE_OPERATIONAL_NEGOTIATION:
nsg = BHSLR_STAGE_FULL_FEATURE_PHASE;
break;
default:
assert(!"invalid csg");
log_errx(1, "invalid csg %d", csg);
}
login_set_csg(request, csg);
login_set_nsg(request, nsg);
memcpy(bhslr->bhslr_isid, &conn->conn_isid, sizeof(bhslr->bhslr_isid));
bhslr->bhslr_tsih = htons(conn->conn_tsih);
bhslr->bhslr_initiator_task_tag = 0;
bhslr->bhslr_cmdsn = 0;
bhslr->bhslr_expstatsn = htonl(conn->conn_statsn + 1);
return (request);
}
static int
login_list_prefers(const char *list,
const char *choice1, const char *choice2)
{
char *tofree, *str, *token;
tofree = str = checked_strdup(list);
while ((token = strsep(&str, ",")) != NULL) {
if (strcmp(token, choice1) == 0) {
free(tofree);
return (1);
}
if (strcmp(token, choice2) == 0) {
free(tofree);
return (2);
}
}
free(tofree);
return (-1);
}
static void
login_negotiate_key(struct connection *conn, const char *name,
const char *value)
{
int which, tmp;
if (strcmp(name, "TargetAlias") == 0) {
strlcpy(conn->conn_target_alias, value,
sizeof(conn->conn_target_alias));
} else if (strcmp(value, "Irrelevant") == 0) {
/* Ignore. */
} else if (strcmp(name, "HeaderDigest") == 0) {
which = login_list_prefers(value, "CRC32C", "None");
switch (which) {
case 1:
log_debugx("target prefers CRC32C "
"for header digest; we'll use it");
conn->conn_header_digest = CONN_DIGEST_CRC32C;
break;
case 2:
log_debugx("target prefers not to do "
"header digest; we'll comply");
break;
default:
log_warnx("target sent unrecognized "
"HeaderDigest value \"%s\"; will use None", value);
break;
}
} else if (strcmp(name, "DataDigest") == 0) {
which = login_list_prefers(value, "CRC32C", "None");
switch (which) {
case 1:
log_debugx("target prefers CRC32C "
"for data digest; we'll use it");
conn->conn_data_digest = CONN_DIGEST_CRC32C;
break;
case 2:
log_debugx("target prefers not to do "
"data digest; we'll comply");
break;
default:
log_warnx("target sent unrecognized "
"DataDigest value \"%s\"; will use None", value);
break;
}
} else if (strcmp(name, "MaxConnections") == 0) {
/* Ignore. */
} else if (strcmp(name, "InitialR2T") == 0) {
if (strcmp(value, "Yes") == 0)
conn->conn_initial_r2t = true;
else
conn->conn_initial_r2t = false;
} else if (strcmp(name, "ImmediateData") == 0) {
if (strcmp(value, "Yes") == 0)
conn->conn_immediate_data = true;
else
conn->conn_immediate_data = false;
} else if (strcmp(name, "MaxRecvDataSegmentLength") == 0) {
tmp = strtoul(value, NULL, 10);
if (tmp <= 0)
log_errx(1, "received invalid "
"MaxRecvDataSegmentLength");
if (tmp > ISCSI_MAX_DATA_SEGMENT_LENGTH) {
log_debugx("capping MaxRecvDataSegmentLength "
"from %d to %d", tmp, ISCSI_MAX_DATA_SEGMENT_LENGTH);
tmp = ISCSI_MAX_DATA_SEGMENT_LENGTH;
}
conn->conn_max_data_segment_length = tmp;
} else if (strcmp(name, "MaxBurstLength") == 0) {
if (conn->conn_immediate_data) {
tmp = strtoul(value, NULL, 10);
if (tmp <= 0)
log_errx(1, "received invalid MaxBurstLength");
conn->conn_max_burst_length = tmp;
}
} else if (strcmp(name, "FirstBurstLength") == 0) {
tmp = strtoul(value, NULL, 10);
if (tmp <= 0)
log_errx(1, "received invalid FirstBurstLength");
conn->conn_first_burst_length = tmp;
} else if (strcmp(name, "DefaultTime2Wait") == 0) {
/* Ignore */
} else if (strcmp(name, "DefaultTime2Retain") == 0) {
/* Ignore */
} else if (strcmp(name, "MaxOutstandingR2T") == 0) {
/* Ignore */
} else if (strcmp(name, "DataPDUInOrder") == 0) {
/* Ignore */
} else if (strcmp(name, "DataSequenceInOrder") == 0) {
/* Ignore */
} else if (strcmp(name, "ErrorRecoveryLevel") == 0) {
/* Ignore */
} else if (strcmp(name, "OFMarker") == 0) {
/* Ignore */
} else if (strcmp(name, "IFMarker") == 0) {
/* Ignore */
} else if (strcmp(name, "TargetPortalGroupTag") == 0) {
/* Ignore */
} else {
log_debugx("unknown key \"%s\"; ignoring", name);
}
}
static void
login_negotiate(struct connection *conn)
{
struct pdu *request, *response;
struct keys *request_keys, *response_keys;
struct iscsi_bhs_login_response *bhslr;
int i, nrequests = 0;
log_debugx("beginning operational parameter negotiation");
request = login_new_request(conn, BHSLR_STAGE_OPERATIONAL_NEGOTIATION);
request_keys = keys_new();
/*
* The following keys are irrelevant for discovery sessions.
*/
if (conn->conn_conf.isc_discovery == 0) {
if (conn->conn_conf.isc_header_digest != 0)
keys_add(request_keys, "HeaderDigest", "CRC32C");
else
keys_add(request_keys, "HeaderDigest", "None");
if (conn->conn_conf.isc_data_digest != 0)
keys_add(request_keys, "DataDigest", "CRC32C");
else
keys_add(request_keys, "DataDigest", "None");
keys_add(request_keys, "ImmediateData", "Yes");
keys_add_int(request_keys, "MaxBurstLength",
2 * ISCSI_MAX_DATA_SEGMENT_LENGTH);
keys_add_int(request_keys, "FirstBurstLength",
ISCSI_MAX_DATA_SEGMENT_LENGTH);
keys_add(request_keys, "InitialR2T", "Yes");
keys_add(request_keys, "MaxOutstandingR2T", "1");
} else {
keys_add(request_keys, "HeaderDigest", "None");
keys_add(request_keys, "DataDigest", "None");
}
keys_add_int(request_keys, "MaxRecvDataSegmentLength",
ISCSI_MAX_DATA_SEGMENT_LENGTH);
keys_add(request_keys, "DefaultTime2Wait", "0");
keys_add(request_keys, "DefaultTime2Retain", "0");
keys_add(request_keys, "ErrorRecoveryLevel", "0");
keys_save(request_keys, request);
keys_delete(request_keys);
request_keys = NULL;
pdu_send(request);
pdu_delete(request);
request = NULL;
response = login_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;
login_negotiate_key(conn,
response_keys->keys_names[i], response_keys->keys_values[i]);
}
keys_delete(response_keys);
response_keys = NULL;
for (;;) {
bhslr = (struct iscsi_bhs_login_response *)response->pdu_bhs;
if ((bhslr->bhslr_flags & BHSLR_FLAGS_TRANSIT) != 0)
break;
nrequests++;
if (nrequests > 5) {
log_warnx("received login response "
"without the \"T\" flag too many times; giving up");
break;
}
log_debugx("received login response "
"without the \"T\" flag; sending another request");
pdu_delete(response);
request = login_new_request(conn,
BHSLR_STAGE_OPERATIONAL_NEGOTIATION);
pdu_send(request);
pdu_delete(request);
response = login_receive(conn);
}
if (login_nsg(response) != BHSLR_STAGE_FULL_FEATURE_PHASE)
log_warnx("received final login response with wrong NSG 0x%x",
login_nsg(response));
pdu_delete(response);
log_debugx("operational parameter negotiation done; "
"transitioning to Full Feature phase");
}
static void
login_send_chap_a(struct connection *conn)
{
struct pdu *request;
struct keys *request_keys;
request = login_new_request(conn, BHSLR_STAGE_SECURITY_NEGOTIATION);
request_keys = keys_new();
keys_add(request_keys, "CHAP_A", "5");
keys_save(request_keys, request);
keys_delete(request_keys);
pdu_send(request);
pdu_delete(request);
}
static void
login_send_chap_r(struct pdu *response)
{
struct connection *conn;
struct pdu *request;
struct keys *request_keys, *response_keys;
struct rchap *rchap;
const char *chap_a, *chap_c, *chap_i;
char *chap_r;
int error;
char *mutual_chap_c, *mutual_chap_i;
/*
* As in the rest of the initiator, 'request' means
* 'initiator -> target', and 'response' means 'target -> initiator',
*
* So, here the 'response' from the target is the packet that contains
* CHAP challenge; our CHAP response goes into 'request'.
*/
conn = response->pdu_connection;
response_keys = keys_new();
keys_load(response_keys, response);
/*
* First, compute the response.
*/
chap_a = keys_find(response_keys, "CHAP_A");
if (chap_a == NULL)
log_errx(1, "received CHAP packet without CHAP_A");
chap_c = keys_find(response_keys, "CHAP_C");
if (chap_c == NULL)
log_errx(1, "received CHAP packet without CHAP_C");
chap_i = keys_find(response_keys, "CHAP_I");
if (chap_i == NULL)
log_errx(1, "received CHAP packet without CHAP_I");
if (strcmp(chap_a, "5") != 0) {
log_errx(1, "received CHAP packet "
"with unsupported CHAP_A \"%s\"", chap_a);
}
rchap = rchap_new(conn->conn_conf.isc_secret);
error = rchap_receive(rchap, chap_i, chap_c);
if (error != 0) {
log_errx(1, "received CHAP packet "
"with malformed CHAP_I or CHAP_C");
}
chap_r = rchap_get_response(rchap);
rchap_delete(rchap);
keys_delete(response_keys);
request = login_new_request(conn, BHSLR_STAGE_SECURITY_NEGOTIATION);
request_keys = keys_new();
keys_add(request_keys, "CHAP_N", conn->conn_conf.isc_user);
keys_add(request_keys, "CHAP_R", chap_r);
free(chap_r);
/*
* If we want mutual authentication, we're expected to send
* our CHAP_I/CHAP_C now.
*/
if (conn->conn_conf.isc_mutual_user[0] != '\0') {
log_debugx("requesting mutual authentication; "
"binary challenge size is %zd bytes",
sizeof(conn->conn_mutual_chap->chap_challenge));
assert(conn->conn_mutual_chap == NULL);
conn->conn_mutual_chap = chap_new();
mutual_chap_i = chap_get_id(conn->conn_mutual_chap);
mutual_chap_c = chap_get_challenge(conn->conn_mutual_chap);
keys_add(request_keys, "CHAP_I", mutual_chap_i);
keys_add(request_keys, "CHAP_C", mutual_chap_c);
free(mutual_chap_i);
free(mutual_chap_c);
}
keys_save(request_keys, request);
keys_delete(request_keys);
pdu_send(request);
pdu_delete(request);
}
static void
login_verify_mutual(const struct pdu *response)
{
struct connection *conn;
struct keys *response_keys;
const char *chap_n, *chap_r;
int error;
conn = response->pdu_connection;
response_keys = keys_new();
keys_load(response_keys, response);
chap_n = keys_find(response_keys, "CHAP_N");
if (chap_n == NULL)
log_errx(1, "received CHAP Response PDU without CHAP_N");
chap_r = keys_find(response_keys, "CHAP_R");
if (chap_r == NULL)
log_errx(1, "received CHAP Response PDU without CHAP_R");
error = chap_receive(conn->conn_mutual_chap, chap_r);
if (error != 0)
log_errx(1, "received CHAP Response PDU with invalid CHAP_R");
if (strcmp(chap_n, conn->conn_conf.isc_mutual_user) != 0) {
fail(conn, "Mutual CHAP failed");
log_errx(1, "mutual CHAP authentication failed: wrong user");
}
error = chap_authenticate(conn->conn_mutual_chap,
conn->conn_conf.isc_mutual_secret);
if (error != 0) {
fail(conn, "Mutual CHAP failed");
log_errx(1, "mutual CHAP authentication failed: wrong secret");
}
keys_delete(response_keys);
chap_delete(conn->conn_mutual_chap);
conn->conn_mutual_chap = NULL;
log_debugx("mutual CHAP authentication succeeded");
}
static void
login_chap(struct connection *conn)
{
struct pdu *response;
log_debugx("beginning CHAP authentication; sending CHAP_A");
login_send_chap_a(conn);
log_debugx("waiting for CHAP_A/CHAP_C/CHAP_I");
response = login_receive(conn);
log_debugx("sending CHAP_N/CHAP_R");
login_send_chap_r(response);
pdu_delete(response);
/*
* XXX: Make sure this is not susceptible to MITM.
*/
log_debugx("waiting for CHAP result");
response = login_receive(conn);
if (conn->conn_conf.isc_mutual_user[0] != '\0')
login_verify_mutual(response);
pdu_delete(response);
log_debugx("CHAP authentication done");
}
void
login(struct connection *conn)
{
struct pdu *request, *response;
struct keys *request_keys, *response_keys;
struct iscsi_bhs_login_response *bhslr2;
const char *auth_method;
int i;
log_debugx("beginning Login phase; sending Login PDU");
request = login_new_request(conn, BHSLR_STAGE_SECURITY_NEGOTIATION);
request_keys = keys_new();
if (conn->conn_conf.isc_mutual_user[0] != '\0') {
keys_add(request_keys, "AuthMethod", "CHAP");
} else if (conn->conn_conf.isc_user[0] != '\0') {
/*
* Give target a chance to skip authentication if it
* doesn't feel like it.
*
* None is first, CHAP second; this is to work around
* what seems to be LIO (Linux target) bug: otherwise,
* if target is configured with no authentication,
* and we are configured to authenticate, the target
* will erroneously respond with AuthMethod=CHAP
* instead of AuthMethod=None, and will subsequently
* fail the connection. This usually happens with
* Discovery sessions, which default to no authentication.
*/
keys_add(request_keys, "AuthMethod", "None,CHAP");
} else {
keys_add(request_keys, "AuthMethod", "None");
}
keys_add(request_keys, "InitiatorName",
conn->conn_conf.isc_initiator);
if (conn->conn_conf.isc_initiator_alias[0] != '\0') {
keys_add(request_keys, "InitiatorAlias",
conn->conn_conf.isc_initiator_alias);
}
if (conn->conn_conf.isc_discovery == 0) {
keys_add(request_keys, "SessionType", "Normal");
keys_add(request_keys,
"TargetName", conn->conn_conf.isc_target);
} else {
keys_add(request_keys, "SessionType", "Discovery");
}
keys_save(request_keys, request);
keys_delete(request_keys);
pdu_send(request);
pdu_delete(request);
response = login_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;
/*
* Not interested in AuthMethod at this point; we only need
* to parse things such as TargetAlias.
*
* XXX: This is somewhat ugly. We should have a way to apply
* all the keys to the session and use that by default
* instead of discarding them.
*/
if (strcmp(response_keys->keys_names[i], "AuthMethod") == 0)
continue;
login_negotiate_key(conn,
response_keys->keys_names[i], response_keys->keys_values[i]);
}
bhslr2 = (struct iscsi_bhs_login_response *)response->pdu_bhs;
if ((bhslr2->bhslr_flags & BHSLR_FLAGS_TRANSIT) != 0 &&
login_nsg(response) == BHSLR_STAGE_OPERATIONAL_NEGOTIATION) {
if (conn->conn_conf.isc_mutual_user[0] != '\0') {
log_errx(1, "target requested transition "
"to operational parameter negotiation, "
"but we require mutual CHAP");
}
log_debugx("target requested transition "
"to operational parameter negotiation");
keys_delete(response_keys);
pdu_delete(response);
login_negotiate(conn);
return;
}
auth_method = keys_find(response_keys, "AuthMethod");
if (auth_method == NULL)
log_errx(1, "received response without AuthMethod");
if (strcmp(auth_method, "None") == 0) {
if (conn->conn_conf.isc_mutual_user[0] != '\0') {
log_errx(1, "target does not require authantication, "
"but we require mutual CHAP");
}
log_debugx("target does not require authentication");
keys_delete(response_keys);
pdu_delete(response);
login_negotiate(conn);
return;
}
if (strcmp(auth_method, "CHAP") != 0) {
fail(conn, "Unsupported AuthMethod");
log_errx(1, "received response "
"with unsupported AuthMethod \"%s\"", auth_method);
}
if (conn->conn_conf.isc_user[0] == '\0' ||
conn->conn_conf.isc_secret[0] == '\0') {
fail(conn, "Authentication required");
log_errx(1, "target requests CHAP authentication, but we don't "
"have user and secret");
}
keys_delete(response_keys);
response_keys = NULL;
pdu_delete(response);
response = NULL;
login_chap(conn);
login_negotiate(conn);
}
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