#ifndef _GPXE_ISCSI_H
#define _GPXE_ISCSI_H
/** @file
*
* iSCSI protocol
*
*/
#include <stdint.h>
#include <gpxe/socket.h>
#include <gpxe/scsi.h>
#include <gpxe/chap.h>
#include <gpxe/refcnt.h>
#include <gpxe/xfer.h>
#include <gpxe/process.h>
/** Default iSCSI port */
#define ISCSI_PORT 3260
/**
* iSCSI segment lengths
*
* iSCSI uses an icky structure with one one-byte field (a dword
* count) and one three-byte field (a byte count). This structure,
* and the accompanying macros, relieve some of the pain.
*/
union iscsi_segment_lengths {
struct {
/** The AHS length (measured in dwords) */
uint8_t ahs_len;
/** The data length (measured in bytes), in network
* byte order
*/
uint8_t data_len[3];
} bytes;
/** Ths data length (measured in bytes), in network byte
* order, with ahs_len as the first byte.
*/
uint32_t ahs_and_data_len;
};
/** The length of the additional header segment, in dwords */
#define ISCSI_AHS_LEN( segment_lengths ) \
( (segment_lengths).bytes.ahs_len )
/** The length of the data segment, in bytes, excluding any padding */
#define ISCSI_DATA_LEN( segment_lengths ) \
( ntohl ( (segment_lengths).ahs_and_data_len ) & 0xffffff )
/** The padding of the data segment, in bytes */
#define ISCSI_DATA_PAD_LEN( segment_lengths ) \
( ( 0 - (segment_lengths).bytes.data_len[2] ) & 0x03 )
/** Set additional header and data segment lengths */
#define ISCSI_SET_LENGTHS( segment_lengths, ahs_len, data_len ) do { \
(segment_lengths).ahs_and_data_len = \
htonl ( data_len | ( ahs_len << 24 ) ); \
} while ( 0 )
/**
* iSCSI basic header segment common fields
*
*/
struct iscsi_bhs_common {
/** Opcode */
uint8_t opcode;
/** Flags */
uint8_t flags;
/** Fields specific to the PDU type */
uint8_t other_a[2];
/** Segment lengths */
union iscsi_segment_lengths lengths;
/** Fields specific to the PDU type */
uint8_t other_b[8];
/** Initiator Task Tag */
uint32_t itt;
/** Fields specific to the PDU type */
uint8_t other_c[28];
};
/** Opcode mask */
#define ISCSI_OPCODE_MASK 0x3f
/** Immediate delivery */
#define ISCSI_FLAG_IMMEDIATE 0x40
/** Final PDU of a sequence */
#define ISCSI_FLAG_FINAL 0x80
/**
* iSCSI basic header segment common request fields
*
*/
struct iscsi_bhs_common_response {
/** Opcode */
uint8_t opcode;
/** Flags */
uint8_t flags;
/** Fields specific to the PDU type */
uint8_t other_a[2];
/** Segment lengths */
union iscsi_segment_lengths lengths;
/** Fields specific to the PDU type */
uint8_t other_b[8];
/** Initiator Task Tag */
uint32_t itt;
/** Fields specific to the PDU type */
uint8_t other_c[4];
/** Status sequence number */
uint32_t statsn;
/** Expected command sequence number */
uint32_t expcmdsn;
/** Fields specific to the PDU type */
uint8_t other_d[16];
};
/**
* iSCSI login request basic header segment
*
*/
struct iscsi_bhs_login_request {
/** Opcode */
uint8_t opcode;
/** Flags */
uint8_t flags;
/** Maximum supported version number */
uint8_t version_max;
/** Minimum supported version number */
uint8_t version_min;
/** Segment lengths */
union iscsi_segment_lengths lengths;
/** Initiator session ID (IANA format) enterprise number and flags */
uint32_t isid_iana_en;
/** Initiator session ID (IANA format) qualifier */
uint16_t isid_iana_qual;
/** Target session identifying handle */
uint16_t tsih;
/** Initiator Task Tag */
uint32_t itt;
/** Connection ID */
uint16_t cid;
/** Reserved */
uint16_t reserved_a;
/** Command sequence number */
uint32_t cmdsn;
/** Expected status sequence number */
uint32_t expstatsn;
/** Reserved */
uint8_t reserved_b[16];
};
/** Login request opcode */
#define ISCSI_OPCODE_LOGIN_REQUEST 0x03
/** Willingness to transition to next stage */
#define ISCSI_LOGIN_FLAG_TRANSITION 0x80
/** Key=value pairs continued in subsequent request */
#define ISCSI_LOGIN_FLAG_CONTINUE 0x40
/* Current stage values and mask */
#define ISCSI_LOGIN_CSG_MASK 0x0c
#define ISCSI_LOGIN_CSG_SECURITY_NEGOTIATION 0x00
#define ISCSI_LOGIN_CSG_OPERATIONAL_NEGOTIATION 0x04
#define ISCSI_LOGIN_CSG_FULL_FEATURE_PHASE 0x0c
/* Next stage values and mask */
#define ISCSI_LOGIN_NSG_MASK 0x03
#define ISCSI_LOGIN_NSG_SECURITY_NEGOTIATION 0x00
#define ISCSI_LOGIN_NSG_OPERATIONAL_NEGOTIATION 0x01
#define ISCSI_LOGIN_NSG_FULL_FEATURE_PHASE 0x03
/** ISID IANA format marker */
#define ISCSI_ISID_IANA 0x40000000
/** Fen Systems Ltd. IANA enterprise number
*
* Permission is hereby granted to use Fen Systems Ltd.'s IANA
* enterprise number with this iSCSI implementation.
*/
#define IANA_EN_FEN_SYSTEMS 10019
/**
* iSCSI login response basic header segment
*
*/
struct iscsi_bhs_login_response {
/** Opcode */
uint8_t opcode;
/** Flags */
uint8_t flags;
/** Maximum supported version number */
uint8_t version_max;
/** Minimum supported version number */
uint8_t version_min;
/** Segment lengths */
union iscsi_segment_lengths lengths;
/** Initiator session ID (IANA format) enterprise number and flags */
uint32_t isid_iana_en;
/** Initiator session ID (IANA format) qualifier */
uint16_t isid_iana_qual;
/** Target session identifying handle */
uint16_t tsih;
/** Initiator Task Tag */
uint32_t itt;
/** Reserved */
uint32_t reserved_a;
/** Status sequence number */
uint32_t statsn;
/** Expected command sequence number */
uint32_t expcmdsn;
/** Maximum command sequence number */
uint32_t maxcmdsn;
/** Status class */
uint8_t status_class;
/** Status detail */
uint8_t status_detail;
/** Reserved */
uint8_t reserved_b[10];
};
/** Login response opcode */
#define ISCSI_OPCODE_LOGIN_RESPONSE 0x23
/* Login response status codes */
#define ISCSI_STATUS_SUCCESS 0x00
#define ISCSI_STATUS_REDIRECT 0x01
#define ISCSI_STATUS_INITIATOR_ERROR 0x02
#define ISCSI_STATUS_INITIATOR_ERROR_AUTHENTICATION 0x01
#define ISCSI_STATUS_INITIATOR_ERROR_AUTHORISATION 0x02
#define ISCSI_STATUS_INITIATOR_ERROR_NOT_FOUND 0x03
#define ISCSI_STATUS_INITIATOR_ERROR_REMOVED 0x04
#define ISCSI_STATUS_TARGET_ERROR 0x03
/**
* iSCSI SCSI command basic header segment
*
*/
struct iscsi_bhs_scsi_command {
/** Opcode */
uint8_t opcode;
/** Flags */
uint8_t flags;
/** Reserved */
uint16_t reserved_a;
/** Segment lengths */
union iscsi_segment_lengths lengths;
/** SCSI Logical Unit Number */
uint64_t lun;
/** Initiator Task Tag */
uint32_t itt;
/** Expected data transfer length */
uint32_t exp_len;
/** Command sequence number */
uint32_t cmdsn;
/** Expected status sequence number */
uint32_t expstatsn;
/** SCSI Command Descriptor Block (CDB) */
union scsi_cdb cdb;
};
/** SCSI command opcode */
#define ISCSI_OPCODE_SCSI_COMMAND 0x01
/** Command will read data */
#define ISCSI_COMMAND_FLAG_READ 0x40
/** Command will write data */
#define ISCSI_COMMAND_FLAG_WRITE 0x20
/* Task attributes */
#define ISCSI_COMMAND_ATTR_UNTAGGED 0x00
#define ISCSI_COMMAND_ATTR_SIMPLE 0x01
#define ISCSI_COMMAND_ATTR_ORDERED 0x02
#define ISCSI_COMMAND_ATTR_HEAD_OF_QUEUE 0x03
#define ISCSI_COMMAND_ATTR_ACA 0x04
/**
* iSCSI SCSI response basic header segment
*
*/
struct iscsi_bhs_scsi_response {
/** Opcode */
uint8_t opcode;
/** Flags */
uint8_t flags;
/** Response code */
uint8_t response;
/** SCSI status code */
uint8_t status;
/** Segment lengths */
union iscsi_segment_lengths lengths;
/** Reserved */
uint8_t reserved_a[8];
/** Initiator Task Tag */
uint32_t itt;
/** SNACK tag */
uint32_t snack;
/** Status sequence number */
uint32_t statsn;
/** Expected command sequence number */
uint32_t expcmdsn;
/** Maximum command sequence number */
uint32_t maxcmdsn;
/** Expected data sequence number */
uint32_t expdatasn;
/** Reserved */
uint8_t reserved_b[8];
};
/** SCSI response opcode */
#define ISCSI_OPCODE_SCSI_RESPONSE 0x21
/** SCSI command completed at target */
#define ISCSI_RESPONSE_COMMAND_COMPLETE 0x00
/** SCSI target failure */
#define ISCSI_RESPONSE_TARGET_FAILURE 0x01
/** SCSI sense response code offset
*
* The SCSI response may contain unsolicited sense data in the data
* segment. If it does, this is the offset to the sense response code
* byte, which is the only byte we care about.
*/
#define ISCSI_SENSE_RESPONSE_CODE_OFFSET 2
/**
* iSCSI data-in basic header segment
*
*/
struct iscsi_bhs_data_in {
/** Opcode */
uint8_t opcode;
/** Flags */
uint8_t flags;
/** Reserved */
uint8_t reserved_a;
/** SCSI status code */
uint8_t status;
/** Segment lengths */
union iscsi_segment_lengths lengths;
/** Logical Unit Number */
uint64_t lun;
/** Initiator Task Tag */
uint32_t itt;
/** Target Transfer Tag */
uint32_t ttt;
/** Status sequence number */
uint32_t statsn;
/** Expected command sequence number */
uint32_t expcmdsn;
/** Maximum command sequence number */
uint32_t maxcmdsn;
/** Data sequence number */
uint32_t datasn;
/** Buffer offset */
uint32_t offset;
/** Residual count */
uint32_t residual_count;
};
/** Data-in opcode */
#define ISCSI_OPCODE_DATA_IN 0x25
/** Data requires acknowledgement */
#define ISCSI_DATA_FLAG_ACKNOWLEDGE 0x40
/** Data overflow occurred */
#define ISCSI_DATA_FLAG_OVERFLOW 0x04
/** Data underflow occurred */
#define ISCSI_DATA_FLAG_UNDERFLOW 0x02
/** SCSI status code and overflow/underflow flags are valid */
#define ISCSI_DATA_FLAG_STATUS 0x01
/**
* iSCSI data-out basic header segment
*
*/
struct iscsi_bhs_data_out {
/** Opcode */
uint8_t opcode;
/** Flags */
uint8_t flags;
/** Reserved */
uint16_t reserved_a;
/** Segment lengths */
union iscsi_segment_lengths lengths;
/** Logical Unit Number */
uint64_t lun;
/** Initiator Task Tag */
uint32_t itt;
/** Target Transfer Tag */
uint32_t ttt;
/** Reserved */
uint32_t reserved_b;
/** Expected status sequence number */
uint32_t expstatsn;
/** Reserved */
uint32_t reserved_c;
/** Data sequence number */
uint32_t datasn;
/** Buffer offset */
uint32_t offset;
/** Reserved */
uint32_t reserved_d;
};
/** Data-out opcode */
#define ISCSI_OPCODE_DATA_OUT 0x05
/**
* iSCSI request to transfer basic header segment
*
*/
struct iscsi_bhs_r2t {
/** Opcode */
uint8_t opcode;
/** Flags */
uint8_t flags;
/** Reserved */
uint16_t reserved_a;
/** Segment lengths */
union iscsi_segment_lengths lengths;
/** Logical Unit Number */
uint64_t lun;
/** Initiator Task Tag */
uint32_t itt;
/** Target Transfer Tag */
uint32_t ttt;
/** Status sequence number */
uint32_t statsn;
/** Expected command sequence number */
uint32_t expcmdsn;
/** Maximum command sequence number */
uint32_t maxcmdsn;
/** R2T sequence number */
uint32_t r2tsn;
/** Buffer offset */
uint32_t offset;
/** Desired data transfer length */
uint32_t len;
};
/** R2T opcode */
#define ISCSI_OPCODE_R2T 0x31
/**
* An iSCSI basic header segment
*/
union iscsi_bhs {
struct iscsi_bhs_common common;
struct iscsi_bhs_common_response common_response;
struct iscsi_bhs_login_request login_request;
struct iscsi_bhs_login_response login_response;
struct iscsi_bhs_scsi_command scsi_command;
struct iscsi_bhs_scsi_response scsi_response;
struct iscsi_bhs_data_in data_in;
struct iscsi_bhs_data_out data_out;
struct iscsi_bhs_r2t r2t;
unsigned char bytes[ sizeof ( struct iscsi_bhs_common ) ];
};
/** State of an iSCSI TX engine */
enum iscsi_tx_state {
/** Nothing to send */
ISCSI_TX_IDLE = 0,
/** Sending the basic header segment */
ISCSI_TX_BHS,
/** Sending the additional header segment */
ISCSI_TX_AHS,
/** Sending the data segment */
ISCSI_TX_DATA,
/** Sending the data segment padding */
ISCSI_TX_DATA_PADDING,
};
/** State of an iSCSI RX engine */
enum iscsi_rx_state {
/** Receiving the basic header segment */
ISCSI_RX_BHS = 0,
/** Receiving the additional header segment */
ISCSI_RX_AHS,
/** Receiving the data segment */
ISCSI_RX_DATA,
/** Receiving the data segment padding */
ISCSI_RX_DATA_PADDING,
};
/** An iSCSI session */
struct iscsi_session {
/** Reference counter */
struct refcnt refcnt;
/** Transport-layer socket */
struct xfer_interface socket;
/** Target address */
char *target_address;
/** Target port */
unsigned int target_port;
/** Target IQN */
char *target_iqn;
/** Logical Unit Number (LUN) */
uint64_t lun;
/** Target socket address (recorded only for iBFT) */
struct sockaddr target_sockaddr;
/** Session status
*
* This is the bitwise-OR of zero or more ISCSI_STATUS_XXX
* constants.
*/
int status;
/** Retry count
*
* Number of times that the connection has been retried.
* Reset upon a successful connection.
*/
int retry_count;
/** Initiator username (if any) */
char *initiator_username;
/** Initiator password (if any) */
char *initiator_password;
/** Target username (if any) */
char *target_username;
/** Target password (if any) */
char *target_password;
/** Target has authenticated acceptably */
int target_auth_ok;
/** CHAP challenge (for target auth only)
*
* This is a block of random data; the first byte is used as
* the CHAP identifier (CHAP_I) and the remainder as the CHAP
* challenge (CHAP_C).
*/
unsigned char chap_challenge[17];
/** CHAP response (used for both initiator and target auth) */
struct chap_response chap;
/** Target session identifying handle
*
* This is assigned by the target when we first log in, and
* must be reused on subsequent login attempts.
*/
uint16_t tsih;
/** Initiator task tag
*
* This is the tag of the current command. It is incremented
* whenever a new command is started.
*/
uint32_t itt;
/** Target transfer tag
*
* This is the tag attached to a sequence of data-out PDUs in
* response to an R2T.
*/
uint32_t ttt;
/**
* Transfer offset
*
* This is the offset for an in-progress sequence of data-out
* PDUs in response to an R2T.
*/
uint32_t transfer_offset;
/**
* Transfer length
*
* This is the length for an in-progress sequence of data-out
* PDUs in response to an R2T.
*/
uint32_t transfer_len;
/** Command sequence number
*
* This is the sequence number of the current command, used to
* fill out the CmdSN field in iSCSI request PDUs. It is
* updated with the value of the ExpCmdSN field whenever we
* receive an iSCSI response PDU containing such a field.
*/
uint32_t cmdsn;
/** Status sequence number
*
* This is the most recent status sequence number present in
* the StatSN field of an iSCSI response PDU containing such a
* field. Whenever we send an iSCSI request PDU, we fill out
* the ExpStatSN field with this value plus one.
*/
uint32_t statsn;
/** Basic header segment for current TX PDU */
union iscsi_bhs tx_bhs;
/** State of the TX engine */
enum iscsi_tx_state tx_state;
/** TX process */
struct process process;
/** Basic header segment for current RX PDU */
union iscsi_bhs rx_bhs;
/** State of the RX engine */
enum iscsi_rx_state rx_state;
/** Byte offset within the current RX state */
size_t rx_offset;
/** Length of the current RX state */
size_t rx_len;
/** Buffer for received data (not always used) */
void *rx_buffer;
/** Current SCSI command
*
* Set to NULL when command is complete.
*/
struct scsi_command *command;
/** SCSI command return code
*
* Set to -EINPROGRESS while command is processing.
*/
int rc;
/** Instant return code
*
* Set to a non-zero value if all requests should return
* immediately. This can be used to e.g. avoid retrying
* logins that are doomed to fail authentication.
*/
int instant_rc;
};
/** iSCSI session is currently in the security negotiation phase */
#define ISCSI_STATUS_SECURITY_NEGOTIATION_PHASE \
( ISCSI_LOGIN_CSG_SECURITY_NEGOTIATION | \
ISCSI_LOGIN_NSG_OPERATIONAL_NEGOTIATION )
/** iSCSI session is currently in the operational parameter
* negotiation phase
*/
#define ISCSI_STATUS_OPERATIONAL_NEGOTIATION_PHASE \
( ISCSI_LOGIN_CSG_OPERATIONAL_NEGOTIATION | \
ISCSI_LOGIN_NSG_FULL_FEATURE_PHASE )
/** iSCSI session is currently in the full feature phase */
#define ISCSI_STATUS_FULL_FEATURE_PHASE ISCSI_LOGIN_CSG_FULL_FEATURE_PHASE
/** Mask for all iSCSI session phases */
#define ISCSI_STATUS_PHASE_MASK ( ISCSI_LOGIN_CSG_MASK | ISCSI_LOGIN_NSG_MASK )
/** iSCSI session needs to send the initial security negotiation strings */
#define ISCSI_STATUS_STRINGS_SECURITY 0x0100
/** iSCSI session needs to send the CHAP_A string */
#define ISCSI_STATUS_STRINGS_CHAP_ALGORITHM 0x0200
/** iSCSI session needs to send the CHAP response */
#define ISCSI_STATUS_STRINGS_CHAP_RESPONSE 0x0400
/** iSCSI session needs to send the mutual CHAP challenge */
#define ISCSI_STATUS_STRINGS_CHAP_CHALLENGE 0x0800
/** iSCSI session needs to send the operational negotiation strings */
#define ISCSI_STATUS_STRINGS_OPERATIONAL 0x1000
/** Mask for all iSCSI "needs to send" flags */
#define ISCSI_STATUS_STRINGS_MASK 0xff00
/** Maximum number of retries at connecting */
#define ISCSI_MAX_RETRIES 2
extern int iscsi_attach ( struct scsi_device *scsi, const char *root_path );
extern void iscsi_detach ( struct scsi_device *scsi );
extern const char * iscsi_initiator_iqn ( void );
#endif /* _GPXE_ISCSI_H */
