freebsd-src/lib/libiscsiutil/libiscsiutil.h
John Baldwin b406897911 iscsi: Handle large Text responses.
Text requests and responses can span multiple PDUs.  In that case, the
sender sets the Continue bit in non-final PDUs and the Final bit in
the last PDU.  The receiver responds to non-final PDUs with an empty
text PDU.

To support this, add a more abstract API in libiscsi which accepts and
receives key sets rather than PDUs.  These routines internally send or
receive one or more PDUs.  Use these new functions to replace the
handling of TextRequest and TextResponse PDUs in discovery sessions in
both ctld and iscsid.

Note that there is not currently a use case for large Text requests
and those are still always sent as a single PDU.  However, discovery
sessions can return a text response listing targets that spans
multiple PDUs, so the new API supports sending and receiving multi-PDU
responses.

Reported by:	Jithesh Arakkan @ Chelsio
Reviewed by:	mav
Sponsored by:	Chelsio Communications
Differential Revision:	https://reviews.freebsd.org/D33548
2021-12-29 14:36:04 -08:00

169 lines
5.3 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2012 The FreeBSD Foundation
*
* 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.
*/
#ifndef __LIBISCSIUTIL_H__
#define __LIBISCSIUTIL_H__
#include <sys/types.h>
#include <stdbool.h>
struct connection_ops;
#define CONN_DIGEST_NONE 0
#define CONN_DIGEST_CRC32C 1
struct connection {
const struct connection_ops *conn_ops;
int conn_socket;
uint8_t conn_isid[6];
uint16_t conn_tsih;
uint32_t conn_cmdsn;
uint32_t conn_statsn;
int conn_header_digest;
int conn_data_digest;
bool conn_immediate_data;
bool conn_use_proxy;
int conn_max_recv_data_segment_length;
int conn_max_send_data_segment_length;
int conn_max_burst_length;
int conn_first_burst_length;
};
struct pdu {
struct connection *pdu_connection;
struct iscsi_bhs *pdu_bhs;
char *pdu_data;
size_t pdu_data_len;
};
struct connection_ops {
bool (*timed_out)(void);
void (*pdu_receive_proxy)(struct pdu *);
void (*pdu_send_proxy)(struct pdu *);
void (*fail)(const struct connection *, const char *);
};
#define KEYS_MAX 1024
struct keys {
char *keys_names[KEYS_MAX];
char *keys_values[KEYS_MAX];
};
#define CHAP_CHALLENGE_LEN 1024
#define CHAP_DIGEST_LEN 16 /* Equal to MD5 digest size. */
struct chap {
unsigned char chap_id;
char chap_challenge[CHAP_CHALLENGE_LEN];
char chap_response[CHAP_DIGEST_LEN];
};
struct rchap {
char *rchap_secret;
unsigned char rchap_id;
void *rchap_challenge;
size_t rchap_challenge_len;
};
struct chap *chap_new(void);
char *chap_get_id(const struct chap *chap);
char *chap_get_challenge(const struct chap *chap);
int chap_receive(struct chap *chap, const char *response);
int chap_authenticate(struct chap *chap,
const char *secret);
void chap_delete(struct chap *chap);
struct rchap *rchap_new(const char *secret);
int rchap_receive(struct rchap *rchap,
const char *id, const char *challenge);
char *rchap_get_response(struct rchap *rchap);
void rchap_delete(struct rchap *rchap);
struct keys *keys_new(void);
void keys_delete(struct keys *key);
void keys_load(struct keys *keys, const char *data,
size_t len);
void keys_save(struct keys *keys, char **datap,
size_t *lenp);
const char *keys_find(struct keys *keys, const char *name);
void keys_add(struct keys *keys,
const char *name, const char *value);
void keys_add_int(struct keys *keys,
const char *name, int value);
static __inline void
keys_load_pdu(struct keys *keys, const struct pdu *pdu)
{
keys_load(keys, pdu->pdu_data, pdu->pdu_data_len);
}
static __inline void
keys_save_pdu(struct keys *keys, struct pdu *pdu)
{
keys_save(keys, &pdu->pdu_data, &pdu->pdu_data_len);
}
struct pdu *pdu_new(struct connection *ic);
struct pdu *pdu_new_response(struct pdu *request);
int pdu_ahs_length(const struct pdu *pdu);
int pdu_data_segment_length(const struct pdu *pdu);
void pdu_set_data_segment_length(struct pdu *pdu,
uint32_t len);
void pdu_receive(struct pdu *request);
void pdu_send(struct pdu *response);
void pdu_delete(struct pdu *ip);
void text_send_request(struct connection *conn,
struct keys *request_keys);
struct keys * text_read_response(struct connection *conn);
struct keys * text_read_request(struct connection *conn,
struct pdu **requestp);
void text_send_response(struct pdu *request,
struct keys *response_keys);
void connection_init(struct connection *conn,
const struct connection_ops *ops, bool use_proxy);
void log_init(int level);
void log_set_peer_name(const char *name);
void log_set_peer_addr(const char *addr);
void log_err(int, const char *, ...)
__dead2 __printflike(2, 3);
void log_errx(int, const char *, ...)
__dead2 __printflike(2, 3);
void log_warn(const char *, ...) __printflike(1, 2);
void log_warnx(const char *, ...) __printflike(1, 2);
void log_debugx(const char *, ...) __printflike(1, 2);
char *checked_strdup(const char *);
#endif /* !__LIBISCSIUTIL_H__ */