diff options
Diffstat (limited to 'src/include')
| -rw-r--r-- | src/include/gpxe/iscsi.h | 460 | ||||
| -rw-r--r-- | src/include/gpxe/scsi.h | 34 |
2 files changed, 494 insertions, 0 deletions
diff --git a/src/include/gpxe/iscsi.h b/src/include/gpxe/iscsi.h new file mode 100644 index 000000000..639da5e57 --- /dev/null +++ b/src/include/gpxe/iscsi.h @@ -0,0 +1,460 @@ +#ifndef _ISCSI_H +#define _ISCSI_H + +/** @file + * + * iSCSI protocol + * + */ + +#include <stdint.h> +#include <gpxe/tcp.h> +#include <gpxe/scsi.h> + +/** + * 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 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 + +/** + * 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 */ + uint8_t lun[8]; + /** 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 + +/** + * 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 */ + uint8_t lun[8]; + /** 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 verflow/underflow flags are valid */ +#define ISCSI_DATA_FLAG_STATUS 0x01 + +/** + * An iSCSI basic header segment + */ +union iscsi_bhs { + struct iscsi_bhs_common common; + 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; + unsigned char bytes[ sizeof ( struct iscsi_bhs_common ) ]; +}; + +/** State */ +enum iscsi_state { + /** In the process of logging in */ + ISCSI_STATE_FAILED = -1, + ISCSI_STATE_NOT_CONNECTED = 0, + ISCSI_STATE_IDLE, + ISCSI_STATE_LOGGING_IN, + ISCSI_STATE_READING_DATA, +}; + +/** 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 { + /** TCP connection for this session */ + struct tcp_connection tcp; + + /** Initiator IQN */ + const char *initiator; + /** Target IQN */ + const char *target; + + /** Block size in bytes */ + size_t block_size; + /** Starting block number of the current data transfer */ + unsigned long block_start; + /** Block count of the current data transfer */ + unsigned long block_count; + /** Block read callback function + * + * Note that this may be called several times, since it is + * called per-packet rather than per-block. + */ + void ( * block_read_callback ) ( void *private, const void *data, + unsigned long offset, size_t len ); + /** Block read callback private data + * + * This is passed to block_read_callback() + */ + void *block_read_private; + + /** State of the session */ + enum iscsi_state state; + /** 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 final response PDU is received. + */ + uint32_t itt; + /** 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; + /** Byte offset within the current TX state */ + size_t tx_offset; + + /** 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; +}; + +static inline int iscsi_busy ( struct iscsi_session *iscsi ) { + return ( iscsi->state > ISCSI_STATE_IDLE ); +} + +static inline int iscsi_error ( struct iscsi_session *iscsi ) { + return ( iscsi->state == ISCSI_STATE_FAILED ); +} + +#endif /* _ISCSI_H */ diff --git a/src/include/gpxe/scsi.h b/src/include/gpxe/scsi.h new file mode 100644 index 000000000..05f9010ce --- /dev/null +++ b/src/include/gpxe/scsi.h @@ -0,0 +1,34 @@ +#ifndef _SCSI_H +#define _SCSI_H + +#include <stdint.h> + +struct scsi_cdb_read_10 { + /** Opcode */ + uint8_t opcode; + /** Flags */ + uint8_t flags; + /** Start address + * + * This is a logical block number, in big-endian order. + */ + uint32_t lba; + /** Group number */ + uint8_t group; + /** Transfer length + * + * This is a logical block count. + */ + uint16_t len; + /** Control byte */ + uint8_t control; +} __attribute__ (( packed )); + +#define SCSI_OPCODE_READ_10 0x28 + +union scsi_cdb { + struct scsi_cdb_read_10 read_10; + char bytes[16]; +}; + +#endif /* _SCSI_H */ |