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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 <assert.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <netinet/in.h>
#include <openssl/err.h>
#include <openssl/md5.h>
#include <openssl/rand.h>
#include "ctld.h"
#include "iscsi_proto.h"
static void login_send_error(struct pdu *request,
char class, char detail);
static void
login_set_nsg(struct pdu *response, int nsg)
{
struct iscsi_bhs_login_response *bhslr;
assert(nsg == BHSLR_STAGE_SECURITY_NEGOTIATION ||
nsg == BHSLR_STAGE_OPERATIONAL_NEGOTIATION ||
nsg == BHSLR_STAGE_FULL_FEATURE_PHASE);
bhslr = (struct iscsi_bhs_login_response *)response->pdu_bhs;
bhslr->bhslr_flags &= 0xFC;
bhslr->bhslr_flags |= nsg;
}
static int
login_csg(const struct pdu *request)
{
struct iscsi_bhs_login_request *bhslr;
bhslr = (struct iscsi_bhs_login_request *)request->pdu_bhs;
return ((bhslr->bhslr_flags & 0x0C) >> 2);
}
static void
login_set_csg(struct pdu *response, int csg)
{
struct iscsi_bhs_login_response *bhslr;
assert(csg == BHSLR_STAGE_SECURITY_NEGOTIATION ||
csg == BHSLR_STAGE_OPERATIONAL_NEGOTIATION ||
csg == BHSLR_STAGE_FULL_FEATURE_PHASE);
bhslr = (struct iscsi_bhs_login_response *)response->pdu_bhs;
bhslr->bhslr_flags &= 0xF3;
bhslr->bhslr_flags |= csg << 2;
}
static struct pdu *
login_receive(struct connection *conn, bool initial)
{
struct pdu *request;
struct iscsi_bhs_login_request *bhslr;
request = pdu_new(conn);
pdu_receive(request);
if ((request->pdu_bhs->bhs_opcode & ~ISCSI_BHS_OPCODE_IMMEDIATE) !=
ISCSI_BHS_OPCODE_LOGIN_REQUEST) {
/*
* The first PDU in session is special - if we receive any PDU
* different than login request, we have to drop the connection
* without sending response ("A target receiving any PDU
* except a Login request before the Login Phase is started MUST
* immediately terminate the connection on which the PDU
* was received.")
*/
if (initial == false)
login_send_error(request, 0x02, 0x0b);
log_errx(1, "protocol error: received invalid opcode 0x%x",
request->pdu_bhs->bhs_opcode);
}
bhslr = (struct iscsi_bhs_login_request *)request->pdu_bhs;
/*
* XXX: Implement the C flag some day.
*/
if ((bhslr->bhslr_flags & BHSLR_FLAGS_CONTINUE) != 0) {
login_send_error(request, 0x03, 0x00);
log_errx(1, "received Login PDU with unsupported \"C\" flag");
}
if (bhslr->bhslr_version_max != 0x00) {
login_send_error(request, 0x02, 0x05);
log_errx(1, "received Login PDU with unsupported "
"Version-max 0x%x", bhslr->bhslr_version_max);
}
if (bhslr->bhslr_version_min != 0x00) {
login_send_error(request, 0x02, 0x05);
log_errx(1, "received Login PDU with unsupported "
"Version-min 0x%x", bhslr->bhslr_version_min);
}
if (ntohl(bhslr->bhslr_cmdsn) < conn->conn_cmdsn) {
login_send_error(request, 0x02, 0x05);
log_errx(1, "received Login PDU with decreasing CmdSN: "
"was %d, is %d", conn->conn_cmdsn,
ntohl(bhslr->bhslr_cmdsn));
}
if (initial == false &&
ntohl(bhslr->bhslr_expstatsn) != conn->conn_statsn) {
login_send_error(request, 0x02, 0x05);
log_errx(1, "received Login PDU with wrong ExpStatSN: "
"is %d, should be %d", ntohl(bhslr->bhslr_expstatsn),
conn->conn_statsn);
}
conn->conn_cmdsn = ntohl(bhslr->bhslr_cmdsn);
return (request);
}
static struct pdu *
login_new_response(struct pdu *request)
{
struct pdu *response;
struct connection *conn;
struct iscsi_bhs_login_request *bhslr;
struct iscsi_bhs_login_response *bhslr2;
bhslr = (struct iscsi_bhs_login_request *)request->pdu_bhs;
conn = request->pdu_connection;
response = pdu_new_response(request);
bhslr2 = (struct iscsi_bhs_login_response *)response->pdu_bhs;
bhslr2->bhslr_opcode = ISCSI_BHS_OPCODE_LOGIN_RESPONSE;
login_set_csg(response, BHSLR_STAGE_SECURITY_NEGOTIATION);
memcpy(bhslr2->bhslr_isid,
bhslr->bhslr_isid, sizeof(bhslr2->bhslr_isid));
bhslr2->bhslr_initiator_task_tag = bhslr->bhslr_initiator_task_tag;
bhslr2->bhslr_statsn = htonl(conn->conn_statsn++);
bhslr2->bhslr_expcmdsn = htonl(conn->conn_cmdsn);
bhslr2->bhslr_maxcmdsn = htonl(conn->conn_cmdsn);
return (response);
}
static void
login_send_error(struct pdu *request, char class, char detail)
{
struct pdu *response;
struct iscsi_bhs_login_response *bhslr2;
log_debugx("sending Login Response PDU with failure class 0x%x/0x%x; "
"see next line for reason", class, detail);
response = login_new_response(request);
bhslr2 = (struct iscsi_bhs_login_response *)response->pdu_bhs;
bhslr2->bhslr_status_class = class;
bhslr2->bhslr_status_detail = detail;
pdu_send(response);
pdu_delete(response);
}
static int
login_list_contains(const char *list, const char *what)
{
char *tofree, *str, *token;
tofree = str = checked_strdup(list);
while ((token = strsep(&str, ",")) != NULL) {
if (strcmp(token, what) == 0) {
free(tofree);
return (1);
}
}
free(tofree);
return (0);
}
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 int
login_hex2int(const char hex)
{
switch (hex) {
case '0':
return (0x00);
case '1':
return (0x01);
case '2':
return (0x02);
case '3':
return (0x03);
case '4':
return (0x04);
case '5':
return (0x05);
case '6':
return (0x06);
case '7':
return (0x07);
case '8':
return (0x08);
case '9':
return (0x09);
case 'a':
case 'A':
return (0x0a);
case 'b':
case 'B':
return (0x0b);
case 'c':
case 'C':
return (0x0c);
case 'd':
case 'D':
return (0x0d);
case 'e':
case 'E':
return (0x0e);
case 'f':
case 'F':
return (0x0f);
default:
return (-1);
}
}
/*
* XXX: Review this _carefully_.
*/
static int
login_hex2bin(const char *hex, char **binp, size_t *bin_lenp)
{
int i, hex_len, nibble;
bool lo = true; /* As opposed to 'hi'. */
char *bin;
size_t bin_off, bin_len;
if (strncasecmp(hex, "0x", strlen("0x")) != 0) {
log_warnx("malformed variable, should start with \"0x\"");
return (-1);
}
hex += strlen("0x");
hex_len = strlen(hex);
if (hex_len < 1) {
log_warnx("malformed variable; doesn't contain anything "
"but \"0x\"");
return (-1);
}
bin_len = hex_len / 2 + hex_len % 2;
bin = calloc(bin_len, 1);
if (bin == NULL)
log_err(1, "calloc");
bin_off = bin_len - 1;
for (i = hex_len - 1; i >= 0; i--) {
nibble = login_hex2int(hex[i]);
if (nibble < 0) {
log_warnx("malformed variable, invalid char \"%c\"",
hex[i]);
return (-1);
}
assert(bin_off < bin_len);
if (lo) {
bin[bin_off] = nibble;
lo = false;
} else {
bin[bin_off] |= nibble << 4;
bin_off--;
lo = true;
}
}
*binp = bin;
*bin_lenp = bin_len;
return (0);
}
static char *
login_bin2hex(const char *bin, size_t bin_len)
{
unsigned char *hex, *tmp, ch;
size_t hex_len;
size_t i;
hex_len = bin_len * 2 + 3; /* +2 for "0x", +1 for '\0'. */
hex = malloc(hex_len);
if (hex == NULL)
log_err(1, "malloc");
tmp = hex;
tmp += sprintf(tmp, "0x");
for (i = 0; i < bin_len; i++) {
ch = bin[i];
tmp += sprintf(tmp, "%02x", ch);
}
return (hex);
}
static void
login_compute_md5(const char id, const char *secret,
const void *challenge, size_t challenge_len, void *response,
size_t response_len)
{
MD5_CTX ctx;
int rv;
assert(response_len == MD5_DIGEST_LENGTH);
MD5_Init(&ctx);
MD5_Update(&ctx, &id, sizeof(id));
MD5_Update(&ctx, secret, strlen(secret));
MD5_Update(&ctx, challenge, challenge_len);
rv = MD5_Final(response, &ctx);
if (rv != 1)
log_errx(1, "MD5_Final");
}
#define LOGIN_CHALLENGE_LEN 1024
static struct pdu *
login_receive_chap_a(struct connection *conn)
{
struct pdu *request;
struct keys *request_keys;
const char *chap_a;
request = login_receive(conn, false);
request_keys = keys_new();
keys_load(request_keys, request);
chap_a = keys_find(request_keys, "CHAP_A");
if (chap_a == NULL) {
login_send_error(request, 0x02, 0x07);
log_errx(1, "received CHAP Login PDU without CHAP_A");
}
if (login_list_contains(chap_a, "5") == 0) {
login_send_error(request, 0x02, 0x01);
log_errx(1, "received CHAP Login PDU with unsupported CHAP_A "
"\"%s\"", chap_a);
}
keys_delete(request_keys);
return (request);
}
static void
login_send_chap_c(struct pdu *request, const unsigned char id,
const void *challenge, const size_t challenge_len)
{
struct pdu *response;
struct keys *response_keys;
char *chap_c, chap_i[4];
chap_c = login_bin2hex(challenge, challenge_len);
snprintf(chap_i, sizeof(chap_i), "%d", id);
response = login_new_response(request);
response_keys = keys_new();
keys_add(response_keys, "CHAP_A", "5");
keys_add(response_keys, "CHAP_I", chap_i);
keys_add(response_keys, "CHAP_C", chap_c);
free(chap_c);
keys_save(response_keys, response);
pdu_send(response);
pdu_delete(response);
keys_delete(response_keys);
}
static struct pdu *
login_receive_chap_r(struct connection *conn,
struct auth_group *ag, const unsigned char id, const void *challenge,
const size_t challenge_len, const struct auth **cap)
{
struct pdu *request;
struct keys *request_keys;
const char *chap_n, *chap_r;
char *response_bin, expected_response_bin[MD5_DIGEST_LENGTH];
size_t response_bin_len;
const struct auth *auth;
int error;
request = login_receive(conn, false);
request_keys = keys_new();
keys_load(request_keys, request);
chap_n = keys_find(request_keys, "CHAP_N");
if (chap_n == NULL) {
login_send_error(request, 0x02, 0x07);
log_errx(1, "received CHAP Login PDU without CHAP_N");
}
chap_r = keys_find(request_keys, "CHAP_R");
if (chap_r == NULL) {
login_send_error(request, 0x02, 0x07);
log_errx(1, "received CHAP Login PDU without CHAP_R");
}
error = login_hex2bin(chap_r, &response_bin, &response_bin_len);
if (error != 0) {
login_send_error(request, 0x02, 0x07);
log_errx(1, "received CHAP Login PDU with malformed CHAP_R");
}
/*
* Verify the response.
*/
assert(ag->ag_type == AG_TYPE_CHAP ||
ag->ag_type == AG_TYPE_CHAP_MUTUAL);
auth = auth_find(ag, chap_n);
if (auth == NULL) {
login_send_error(request, 0x02, 0x01);
log_errx(1, "received CHAP Login with invalid user \"%s\"",
chap_n);
}
assert(auth->a_secret != NULL);
assert(strlen(auth->a_secret) > 0);
login_compute_md5(id, auth->a_secret, challenge,
challenge_len, expected_response_bin,
sizeof(expected_response_bin));
if (memcmp(response_bin, expected_response_bin,
sizeof(expected_response_bin)) != 0) {
login_send_error(request, 0x02, 0x01);
log_errx(1, "CHAP authentication failed for user \"%s\"",
auth->a_user);
}
keys_delete(request_keys);
free(response_bin);
*cap = auth;
return (request);
}
static void
login_send_chap_success(struct pdu *request,
const struct auth *auth)
{
struct pdu *response;
struct keys *request_keys, *response_keys;
struct iscsi_bhs_login_response *bhslr2;
const char *chap_i, *chap_c;
char *chap_r, *challenge, response_bin[MD5_DIGEST_LENGTH];
size_t challenge_len;
unsigned char id;
int error;
response = login_new_response(request);
bhslr2 = (struct iscsi_bhs_login_response *)response->pdu_bhs;
bhslr2->bhslr_flags |= BHSLR_FLAGS_TRANSIT;
login_set_nsg(response, BHSLR_STAGE_OPERATIONAL_NEGOTIATION);
/*
* Actually, one more thing: mutual authentication.
*/
request_keys = keys_new();
keys_load(request_keys, request);
chap_i = keys_find(request_keys, "CHAP_I");
chap_c = keys_find(request_keys, "CHAP_C");
if (chap_i != NULL || chap_c != NULL) {
if (chap_i == NULL) {
login_send_error(request, 0x02, 0x07);
log_errx(1, "initiator requested target "
"authentication, but didn't send CHAP_I");
}
if (chap_c == NULL) {
login_send_error(request, 0x02, 0x07);
log_errx(1, "initiator requested target "
"authentication, but didn't send CHAP_C");
}
if (auth->a_auth_group->ag_type != AG_TYPE_CHAP_MUTUAL) {
login_send_error(request, 0x02, 0x01);
log_errx(1, "initiator requests target authentication "
"for user \"%s\", but mutual user/secret "
"is not set", auth->a_user);
}
id = strtoul(chap_i, NULL, 10);
error = login_hex2bin(chap_c, &challenge, &challenge_len);
if (error != 0) {
login_send_error(request, 0x02, 0x07);
log_errx(1, "received CHAP Login PDU with malformed "
"CHAP_C");
}
log_debugx("performing mutual authentication as user \"%s\"",
auth->a_mutual_user);
login_compute_md5(id, auth->a_mutual_secret, challenge,
challenge_len, response_bin, sizeof(response_bin));
chap_r = login_bin2hex(response_bin,
sizeof(response_bin));
response_keys = keys_new();
keys_add(response_keys, "CHAP_N", auth->a_mutual_user);
keys_add(response_keys, "CHAP_R", chap_r);
free(chap_r);
keys_save(response_keys, response);
keys_delete(response_keys);
} else {
log_debugx("initiator did not request target authentication");
}
keys_delete(request_keys);
pdu_send(response);
pdu_delete(response);
}
static void
login_chap(struct connection *conn, struct auth_group *ag)
{
const struct auth *auth;
struct pdu *request;
char challenge_bin[LOGIN_CHALLENGE_LEN];
unsigned char id;
int rv;
/*
* Receive CHAP_A PDU.
*/
log_debugx("beginning CHAP authentication; waiting for CHAP_A");
request = login_receive_chap_a(conn);
/*
* Generate the challenge.
*/
rv = RAND_bytes(challenge_bin, sizeof(challenge_bin));
if (rv != 1) {
login_send_error(request, 0x03, 0x02);
log_errx(1, "RAND_bytes failed: %s",
ERR_error_string(ERR_get_error(), NULL));
}
rv = RAND_bytes(&id, sizeof(id));
if (rv != 1) {
login_send_error(request, 0x03, 0x02);
log_errx(1, "RAND_bytes failed: %s",
ERR_error_string(ERR_get_error(), NULL));
}
/*
* Send the challenge.
*/
log_debugx("sending CHAP_C, binary challenge size is %zd bytes",
sizeof(challenge_bin));
login_send_chap_c(request, id, challenge_bin,
sizeof(challenge_bin));
pdu_delete(request);
/*
* Receive CHAP_N/CHAP_R PDU and authenticate.
*/
log_debugx("waiting for CHAP_N/CHAP_R");
request = login_receive_chap_r(conn, ag, id, challenge_bin,
sizeof(challenge_bin), &auth);
/*
* Yay, authentication succeeded!
*/
log_debugx("authentication succeeded for user \"%s\"; "
"transitioning to Negotiation Phase", auth->a_user);
login_send_chap_success(request, auth);
pdu_delete(request);
}
static void
login_negotiate_key(struct pdu *request, const char *name,
const char *value, bool skipped_security, struct keys *response_keys)
{
int which, tmp;
struct connection *conn;
conn = request->pdu_connection;
if (strcmp(name, "InitiatorName") == 0) {
if (!skipped_security)
log_errx(1, "initiator resent InitiatorName");
} else if (strcmp(name, "SessionType") == 0) {
if (!skipped_security)
log_errx(1, "initiator resent SessionType");
} else if (strcmp(name, "TargetName") == 0) {
if (!skipped_security)
log_errx(1, "initiator resent TargetName");
} else if (strcmp(name, "InitiatorAlias") == 0) {
if (conn->conn_initiator_alias != NULL)
free(conn->conn_initiator_alias);
conn->conn_initiator_alias = checked_strdup(value);
} else if (strcmp(value, "Irrelevant") == 0) {
/* Ignore. */
} else if (strcmp(name, "HeaderDigest") == 0) {
/*
* We don't handle digests for discovery sessions.
*/
if (conn->conn_session_type == CONN_SESSION_TYPE_DISCOVERY) {
log_debugx("discovery session; digests disabled");
keys_add(response_keys, name, "None");
return;
}
which = login_list_prefers(value, "CRC32C", "None");
switch (which) {
case 1:
log_debugx("initiator prefers CRC32C "
"for header digest; we'll use it");
conn->conn_header_digest = CONN_DIGEST_CRC32C;
keys_add(response_keys, name, "CRC32C");
break;
case 2:
log_debugx("initiator prefers not to do "
"header digest; we'll comply");
keys_add(response_keys, name, "None");
break;
default:
log_warnx("initiator sent unrecognized "
"HeaderDigest value \"%s\"; will use None", value);
keys_add(response_keys, name, "None");
break;
}
} else if (strcmp(name, "DataDigest") == 0) {
if (conn->conn_session_type == CONN_SESSION_TYPE_DISCOVERY) {
log_debugx("discovery session; digests disabled");
keys_add(response_keys, name, "None");
return;
}
which = login_list_prefers(value, "CRC32C", "None");
switch (which) {
case 1:
log_debugx("initiator prefers CRC32C "
"for data digest; we'll use it");
conn->conn_data_digest = CONN_DIGEST_CRC32C;
keys_add(response_keys, name, "CRC32C");
break;
case 2:
log_debugx("initiator prefers not to do "
"data digest; we'll comply");
keys_add(response_keys, name, "None");
break;
default:
log_warnx("initiator sent unrecognized "
"DataDigest value \"%s\"; will use None", value);
keys_add(response_keys, name, "None");
break;
}
} else if (strcmp(name, "MaxConnections") == 0) {
keys_add(response_keys, name, "1");
} else if (strcmp(name, "InitialR2T") == 0) {
keys_add(response_keys, name, "Yes");
} else if (strcmp(name, "ImmediateData") == 0) {
if (conn->conn_session_type == CONN_SESSION_TYPE_DISCOVERY) {
log_debugx("discovery session; ImmediateData irrelevant");
keys_add(response_keys, name, "Irrelevant");
} else {
if (strcmp(value, "Yes") == 0) {
conn->conn_immediate_data = true;
keys_add(response_keys, name, "Yes");
} else {
conn->conn_immediate_data = false;
keys_add(response_keys, name, "No");
}
}
} else if (strcmp(name, "MaxRecvDataSegmentLength") == 0) {
tmp = strtoul(value, NULL, 10);
if (tmp <= 0) {
login_send_error(request, 0x02, 0x00);
log_errx(1, "received invalid "
"MaxRecvDataSegmentLength");
}
if (tmp > MAX_DATA_SEGMENT_LENGTH) {
log_debugx("capping MaxRecvDataSegmentLength "
"from %d to %d", tmp, MAX_DATA_SEGMENT_LENGTH);
tmp = MAX_DATA_SEGMENT_LENGTH;
}
conn->conn_max_data_segment_length = tmp;
keys_add_int(response_keys, name, tmp);
} else if (strcmp(name, "MaxBurstLength") == 0) {
tmp = strtoul(value, NULL, 10);
if (tmp <= 0) {
login_send_error(request, 0x02, 0x00);
log_errx(1, "received invalid MaxBurstLength");
}
if (tmp > MAX_BURST_LENGTH) {
log_debugx("capping MaxBurstLength from %d to %d",
tmp, MAX_BURST_LENGTH);
tmp = MAX_BURST_LENGTH;
}
conn->conn_max_burst_length = tmp;
keys_add(response_keys, name, value);
} else if (strcmp(name, "FirstBurstLength") == 0) {
tmp = strtoul(value, NULL, 10);
if (tmp <= 0) {
login_send_error(request, 0x02, 0x00);
log_errx(1, "received invalid "
"FirstBurstLength");
}
if (tmp > MAX_DATA_SEGMENT_LENGTH) {
log_debugx("capping FirstBurstLength from %d to %d",
tmp, MAX_DATA_SEGMENT_LENGTH);
tmp = MAX_DATA_SEGMENT_LENGTH;
}
/*
* We don't pass the value to the kernel; it only enforces
* hardcoded limit anyway.
*/
keys_add_int(response_keys, name, tmp);
} else if (strcmp(name, "DefaultTime2Wait") == 0) {
keys_add(response_keys, name, value);
} else if (strcmp(name, "DefaultTime2Retain") == 0) {
keys_add(response_keys, name, "0");
} else if (strcmp(name, "MaxOutstandingR2T") == 0) {
keys_add(response_keys, name, "1");
} else if (strcmp(name, "DataPDUInOrder") == 0) {
keys_add(response_keys, name, "Yes");
} else if (strcmp(name, "DataSequenceInOrder") == 0) {
keys_add(response_keys, name, "Yes");
} else if (strcmp(name, "ErrorRecoveryLevel") == 0) {
keys_add(response_keys, name, "0");
} else if (strcmp(name, "OFMarker") == 0) {
keys_add(response_keys, name, "No");
} else if (strcmp(name, "IFMarker") == 0) {
keys_add(response_keys, name, "No");
} else {
log_debugx("unknown key \"%s\"; responding "
"with NotUnderstood", name);
keys_add(response_keys, name, "NotUnderstood");
}
}
static void
login_negotiate(struct connection *conn, struct pdu *request)
{
struct pdu *response;
struct iscsi_bhs_login_response *bhslr2;
struct keys *request_keys, *response_keys;
int i;
bool skipped_security;
if (request == NULL) {
log_debugx("beginning operational parameter negotiation; "
"waiting for Login PDU");
request = login_receive(conn, false);
skipped_security = false;
} else
skipped_security = true;
request_keys = keys_new();
keys_load(request_keys, request);
response = login_new_response(request);
bhslr2 = (struct iscsi_bhs_login_response *)response->pdu_bhs;
bhslr2->bhslr_flags |= BHSLR_FLAGS_TRANSIT;
bhslr2->bhslr_tsih = htons(0xbadd);
login_set_csg(response, BHSLR_STAGE_OPERATIONAL_NEGOTIATION);
login_set_nsg(response, BHSLR_STAGE_FULL_FEATURE_PHASE);
response_keys = keys_new();
if (skipped_security &&
conn->conn_session_type == CONN_SESSION_TYPE_NORMAL) {
if (conn->conn_target->t_alias != NULL)
keys_add(response_keys,
"TargetAlias", conn->conn_target->t_alias);
keys_add_int(response_keys, "TargetPortalGroupTag",
conn->conn_portal->p_portal_group->pg_tag);
}
for (i = 0; i < KEYS_MAX; i++) {
if (request_keys->keys_names[i] == NULL)
break;
login_negotiate_key(request, request_keys->keys_names[i],
request_keys->keys_values[i], skipped_security,
response_keys);
}
log_debugx("operational parameter negotiation done; "
"transitioning to Full Feature Phase");
keys_save(response_keys, response);
pdu_send(response);
pdu_delete(response);
keys_delete(response_keys);
pdu_delete(request);
keys_delete(request_keys);
}
void
login(struct connection *conn)
{
struct pdu *request, *response;
struct iscsi_bhs_login_request *bhslr;
struct iscsi_bhs_login_response *bhslr2;
struct keys *request_keys, *response_keys;
struct auth_group *ag;
const char *initiator_name, *initiator_alias, *session_type,
*target_name, *auth_method;
/*
* Handle the initial Login Request - figure out required authentication
* method and either transition to the next phase, if no authentication
* is required, or call appropriate authentication code.
*/
log_debugx("beginning Login Phase; waiting for Login PDU");
request = login_receive(conn, true);
bhslr = (struct iscsi_bhs_login_request *)request->pdu_bhs;
if (bhslr->bhslr_tsih != 0) {
login_send_error(request, 0x02, 0x0a);
log_errx(1, "received Login PDU with non-zero TSIH");
}
memcpy(conn->conn_initiator_isid, bhslr->bhslr_isid,
sizeof(conn->conn_initiator_isid));
/*
* XXX: Implement the C flag some day.
*/
request_keys = keys_new();
keys_load(request_keys, request);
assert(conn->conn_initiator_name == NULL);
initiator_name = keys_find(request_keys, "InitiatorName");
if (initiator_name == NULL) {
login_send_error(request, 0x02, 0x07);
log_errx(1, "received Login PDU without InitiatorName");
}
if (valid_iscsi_name(initiator_name) == false) {
login_send_error(request, 0x02, 0x00);
log_errx(1, "received Login PDU with invalid InitiatorName");
}
conn->conn_initiator_name = checked_strdup(initiator_name);
log_set_peer_name(conn->conn_initiator_name);
/*
* XXX: This doesn't work (does nothing) because of Capsicum.
*/
setproctitle("%s (%s)", conn->conn_initiator_addr, conn->conn_initiator_name);
initiator_alias = keys_find(request_keys, "InitiatorAlias");
if (initiator_alias != NULL)
conn->conn_initiator_alias = checked_strdup(initiator_alias);
assert(conn->conn_session_type == CONN_SESSION_TYPE_NONE);
session_type = keys_find(request_keys, "SessionType");
if (session_type != NULL) {
if (strcmp(session_type, "Normal") == 0) {
conn->conn_session_type = CONN_SESSION_TYPE_NORMAL;
} else if (strcmp(session_type, "Discovery") == 0) {
conn->conn_session_type = CONN_SESSION_TYPE_DISCOVERY;
} else {
login_send_error(request, 0x02, 0x00);
log_errx(1, "received Login PDU with invalid "
"SessionType \"%s\"", session_type);
}
} else
conn->conn_session_type = CONN_SESSION_TYPE_NORMAL;
assert(conn->conn_target == NULL);
if (conn->conn_session_type == CONN_SESSION_TYPE_NORMAL) {
target_name = keys_find(request_keys, "TargetName");
if (target_name == NULL) {
login_send_error(request, 0x02, 0x07);
log_errx(1, "received Login PDU without TargetName");
}
conn->conn_target =
target_find(conn->conn_portal->p_portal_group->pg_conf,
target_name);
if (conn->conn_target == NULL) {
login_send_error(request, 0x02, 0x03);
log_errx(1, "requested target \"%s\" not found",
target_name);
}
}
/*
* At this point we know what kind of authentication we need.
*/
if (conn->conn_session_type == CONN_SESSION_TYPE_NORMAL) {
ag = conn->conn_target->t_auth_group;
if (ag->ag_name != NULL) {
log_debugx("initiator requests to connect "
"to target \"%s\"; auth-group \"%s\"",
conn->conn_target->t_name,
conn->conn_target->t_auth_group->ag_name);
} else {
log_debugx("initiator requests to connect "
"to target \"%s\"", conn->conn_target->t_name);
}
} else {
assert(conn->conn_session_type == CONN_SESSION_TYPE_DISCOVERY);
ag = conn->conn_portal->p_portal_group->pg_discovery_auth_group;
if (ag->ag_name != NULL) {
log_debugx("initiator requests "
"discovery session; auth-group \"%s\"", ag->ag_name);
} else {
log_debugx("initiator requests discovery session");
}
}
/*
* Enforce initiator-name and initiator-portal.
*/
if (auth_name_defined(ag)) {
if (auth_name_find(ag, initiator_name) == NULL) {
login_send_error(request, 0x02, 0x02);
log_errx(1, "initiator does not match allowed "
"initiator names");
}
log_debugx("initiator matches allowed initiator names");
} else {
log_debugx("auth-group does not define initiator name "
"restrictions");
}
if (auth_portal_defined(ag)) {
if (auth_portal_find(ag, &conn->conn_initiator_sa) == NULL) {
login_send_error(request, 0x02, 0x02);
log_errx(1, "initiator does not match allowed "
"initiator portals");
}
log_debugx("initiator matches allowed initiator portals");
} else {
log_debugx("auth-group does not define initiator portal "
"restrictions");
}
/*
* Let's see if the initiator intends to do any kind of authentication
* at all.
*/
if (login_csg(request) == BHSLR_STAGE_OPERATIONAL_NEGOTIATION) {
if (ag->ag_type != AG_TYPE_NO_AUTHENTICATION) {
login_send_error(request, 0x02, 0x01);
log_errx(1, "initiator skipped the authentication, "
"but authentication is required");
}
keys_delete(request_keys);
log_debugx("initiator skipped the authentication, "
"and we don't need it; proceeding with negotiation");
login_negotiate(conn, request);
return;
}
if (ag->ag_type == AG_TYPE_NO_AUTHENTICATION) {
/*
* Initiator might want to to authenticate,
* but we don't need it.
*/
log_debugx("authentication not required; "
"transitioning to operational parameter negotiation");
if ((bhslr->bhslr_flags & BHSLR_FLAGS_TRANSIT) == 0)
log_warnx("initiator did not set the \"T\" flag; "
"transitioning anyway");
response = login_new_response(request);
bhslr2 = (struct iscsi_bhs_login_response *)response->pdu_bhs;
bhslr2->bhslr_flags |= BHSLR_FLAGS_TRANSIT;
login_set_nsg(response,
BHSLR_STAGE_OPERATIONAL_NEGOTIATION);
response_keys = keys_new();
/*
* Required by Linux initiator.
*/
auth_method = keys_find(request_keys, "AuthMethod");
if (auth_method != NULL &&
login_list_contains(auth_method, "None"))
keys_add(response_keys, "AuthMethod", "None");
if (conn->conn_session_type == CONN_SESSION_TYPE_NORMAL) {
if (conn->conn_target->t_alias != NULL)
keys_add(response_keys,
"TargetAlias", conn->conn_target->t_alias);
keys_add_int(response_keys, "TargetPortalGroupTag",
conn->conn_portal->p_portal_group->pg_tag);
}
keys_save(response_keys, response);
pdu_send(response);
pdu_delete(response);
keys_delete(response_keys);
pdu_delete(request);
keys_delete(request_keys);
login_negotiate(conn, NULL);
return;
}
if (ag->ag_type == AG_TYPE_DENY) {
login_send_error(request, 0x02, 0x01);
log_errx(1, "auth-type is \"deny\"");
}
if (ag->ag_type == AG_TYPE_UNKNOWN) {
/*
* This can happen with empty auth-group.
*/
login_send_error(request, 0x02, 0x01);
log_errx(1, "auth-type not set, denying access");
}
log_debugx("CHAP authentication required");
auth_method = keys_find(request_keys, "AuthMethod");
if (auth_method == NULL) {
login_send_error(request, 0x02, 0x07);
log_errx(1, "received Login PDU without AuthMethod");
}
/*
* XXX: This should be Reject, not just a login failure (5.3.2).
*/
if (login_list_contains(auth_method, "CHAP") == 0) {
login_send_error(request, 0x02, 0x01);
log_errx(1, "initiator requests unsupported AuthMethod \"%s\" "
"instead of \"CHAP\"", auth_method);
}
response = login_new_response(request);
response_keys = keys_new();
keys_add(response_keys, "AuthMethod", "CHAP");
if (conn->conn_session_type == CONN_SESSION_TYPE_NORMAL) {
if (conn->conn_target->t_alias != NULL)
keys_add(response_keys,
"TargetAlias", conn->conn_target->t_alias);
keys_add_int(response_keys, "TargetPortalGroupTag",
conn->conn_portal->p_portal_group->pg_tag);
}
keys_save(response_keys, response);
pdu_send(response);
pdu_delete(response);
keys_delete(response_keys);
pdu_delete(request);
keys_delete(request_keys);
login_chap(conn, ag);
login_negotiate(conn, NULL);
}
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