diff options
Diffstat (limited to 'debian/grub-extras/disabled/gpxe/src/net/tcp/iscsi.c')
| -rw-r--r-- | debian/grub-extras/disabled/gpxe/src/net/tcp/iscsi.c | 1934 |
1 files changed, 1934 insertions, 0 deletions
diff --git a/debian/grub-extras/disabled/gpxe/src/net/tcp/iscsi.c b/debian/grub-extras/disabled/gpxe/src/net/tcp/iscsi.c new file mode 100644 index 0000000..771384b --- /dev/null +++ b/debian/grub-extras/disabled/gpxe/src/net/tcp/iscsi.c @@ -0,0 +1,1934 @@ +/* + * Copyright (C) 2006 Michael Brown <mbrown@fensystems.co.uk>. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of the + * License, or any later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +FILE_LICENCE ( GPL2_OR_LATER ); + +#include <stddef.h> +#include <string.h> +#include <stdlib.h> +#include <stdio.h> +#include <errno.h> +#include <assert.h> +#include <byteswap.h> +#include <gpxe/vsprintf.h> +#include <gpxe/socket.h> +#include <gpxe/xfer.h> +#include <gpxe/open.h> +#include <gpxe/scsi.h> +#include <gpxe/process.h> +#include <gpxe/uaccess.h> +#include <gpxe/tcpip.h> +#include <gpxe/settings.h> +#include <gpxe/features.h> +#include <gpxe/iscsi.h> + +/** @file + * + * iSCSI protocol + * + */ + +FEATURE ( FEATURE_PROTOCOL, "iSCSI", DHCP_EB_FEATURE_ISCSI, 1 ); + +/** iSCSI initiator name (explicitly specified) */ +static char *iscsi_explicit_initiator_iqn; + +/** Default iSCSI initiator name (constructed from hostname) */ +static char *iscsi_default_initiator_iqn; + +/** iSCSI initiator username */ +static char *iscsi_initiator_username; + +/** iSCSI initiator password */ +static char *iscsi_initiator_password; + +/** iSCSI target username */ +static char *iscsi_target_username; + +/** iSCSI target password */ +static char *iscsi_target_password; + +static void iscsi_start_tx ( struct iscsi_session *iscsi ); +static void iscsi_start_login ( struct iscsi_session *iscsi ); +static void iscsi_start_data_out ( struct iscsi_session *iscsi, + unsigned int datasn ); + +/** + * Finish receiving PDU data into buffer + * + * @v iscsi iSCSI session + */ +static void iscsi_rx_buffered_data_done ( struct iscsi_session *iscsi ) { + free ( iscsi->rx_buffer ); + iscsi->rx_buffer = NULL; +} + +/** + * Free iSCSI session + * + * @v refcnt Reference counter + */ +static void iscsi_free ( struct refcnt *refcnt ) { + struct iscsi_session *iscsi = + container_of ( refcnt, struct iscsi_session, refcnt ); + + free ( iscsi->target_address ); + free ( iscsi->target_iqn ); + free ( iscsi->initiator_username ); + free ( iscsi->initiator_password ); + free ( iscsi->target_username ); + free ( iscsi->target_password ); + chap_finish ( &iscsi->chap ); + iscsi_rx_buffered_data_done ( iscsi ); + free ( iscsi ); +} + +/** + * Open iSCSI transport-layer connection + * + * @v iscsi iSCSI session + * @ret rc Return status code + */ +static int iscsi_open_connection ( struct iscsi_session *iscsi ) { + struct sockaddr_tcpip target; + int rc; + + assert ( iscsi->tx_state == ISCSI_TX_IDLE ); + assert ( iscsi->rx_state == ISCSI_RX_BHS ); + assert ( iscsi->rx_offset == 0 ); + + /* Open socket */ + memset ( &target, 0, sizeof ( target ) ); + target.st_port = htons ( iscsi->target_port ); + if ( ( rc = xfer_open_named_socket ( &iscsi->socket, SOCK_STREAM, + ( struct sockaddr * ) &target, + iscsi->target_address, + NULL ) ) != 0 ) { + DBGC ( iscsi, "iSCSI %p could not open socket: %s\n", + iscsi, strerror ( rc ) ); + return rc; + } + + /* Enter security negotiation phase */ + iscsi->status = ( ISCSI_STATUS_SECURITY_NEGOTIATION_PHASE | + ISCSI_STATUS_STRINGS_SECURITY ); + if ( iscsi->target_username ) + iscsi->status |= ISCSI_STATUS_AUTH_REVERSE_REQUIRED; + + /* Assign fresh initiator task tag */ + iscsi->itt++; + + /* Initiate login */ + iscsi_start_login ( iscsi ); + + return 0; +} + +/** + * Close iSCSI transport-layer connection + * + * @v iscsi iSCSI session + * @v rc Reason for close + * + * Closes the transport-layer connection and resets the session state + * ready to attempt a fresh login. + */ +static void iscsi_close_connection ( struct iscsi_session *iscsi, int rc ) { + + /* Close all data transfer interfaces */ + xfer_close ( &iscsi->socket, rc ); + + /* Clear connection status */ + iscsi->status = 0; + + /* Reset TX and RX state machines */ + iscsi->tx_state = ISCSI_TX_IDLE; + iscsi->rx_state = ISCSI_RX_BHS; + iscsi->rx_offset = 0; + + /* Free any temporary dynamically allocated memory */ + chap_finish ( &iscsi->chap ); + iscsi_rx_buffered_data_done ( iscsi ); +} + +/** + * Mark iSCSI SCSI operation as complete + * + * @v iscsi iSCSI session + * @v rc Return status code + * + * Note that iscsi_scsi_done() will not close the connection, and must + * therefore be called only when the internal state machines are in an + * appropriate state, otherwise bad things may happen on the next call + * to iscsi_issue(). The general rule is to call iscsi_scsi_done() + * only at the end of receiving a PDU; at this point the TX and RX + * engines should both be idle. + */ +static void iscsi_scsi_done ( struct iscsi_session *iscsi, int rc ) { + + assert ( iscsi->tx_state == ISCSI_TX_IDLE ); + assert ( iscsi->command != NULL ); + + iscsi->command->rc = rc; + iscsi->command = NULL; +} + +/**************************************************************************** + * + * iSCSI SCSI command issuing + * + */ + +/** + * Build iSCSI SCSI command BHS + * + * @v iscsi iSCSI session + * + * We don't currently support bidirectional commands (i.e. with both + * Data-In and Data-Out segments); these would require providing code + * to generate an AHS, and there doesn't seem to be any need for it at + * the moment. + */ +static void iscsi_start_command ( struct iscsi_session *iscsi ) { + struct iscsi_bhs_scsi_command *command = &iscsi->tx_bhs.scsi_command; + + assert ( ! ( iscsi->command->data_in && iscsi->command->data_out ) ); + + /* Construct BHS and initiate transmission */ + iscsi_start_tx ( iscsi ); + command->opcode = ISCSI_OPCODE_SCSI_COMMAND; + command->flags = ( ISCSI_FLAG_FINAL | + ISCSI_COMMAND_ATTR_SIMPLE ); + if ( iscsi->command->data_in ) + command->flags |= ISCSI_COMMAND_FLAG_READ; + if ( iscsi->command->data_out ) + command->flags |= ISCSI_COMMAND_FLAG_WRITE; + /* lengths left as zero */ + command->lun = iscsi->lun; + command->itt = htonl ( ++iscsi->itt ); + command->exp_len = htonl ( iscsi->command->data_in_len | + iscsi->command->data_out_len ); + command->cmdsn = htonl ( iscsi->cmdsn ); + command->expstatsn = htonl ( iscsi->statsn + 1 ); + memcpy ( &command->cdb, &iscsi->command->cdb, sizeof ( command->cdb )); + DBGC2 ( iscsi, "iSCSI %p start " SCSI_CDB_FORMAT " %s %#zx\n", + iscsi, SCSI_CDB_DATA ( command->cdb ), + ( iscsi->command->data_in ? "in" : "out" ), + ( iscsi->command->data_in ? + iscsi->command->data_in_len : + iscsi->command->data_out_len ) ); +} + +/** + * Receive data segment of an iSCSI SCSI response PDU + * + * @v iscsi iSCSI session + * @v data Received data + * @v len Length of received data + * @v remaining Data remaining after this data + * @ret rc Return status code + */ +static int iscsi_rx_scsi_response ( struct iscsi_session *iscsi, + const void *data, size_t len, + size_t remaining ) { + struct iscsi_bhs_scsi_response *response + = &iscsi->rx_bhs.scsi_response; + int sense_offset; + + /* Capture the sense response code as it floats past, if present */ + sense_offset = ISCSI_SENSE_RESPONSE_CODE_OFFSET - iscsi->rx_offset; + if ( ( sense_offset >= 0 ) && len ) { + iscsi->command->sense_response = + * ( ( char * ) data + sense_offset ); + } + + /* Wait for whole SCSI response to arrive */ + if ( remaining ) + return 0; + + /* Record SCSI status code */ + iscsi->command->status = response->status; + + /* Check for errors */ + if ( response->response != ISCSI_RESPONSE_COMMAND_COMPLETE ) + return -EIO; + + /* Mark as completed */ + iscsi_scsi_done ( iscsi, 0 ); + return 0; +} + +/** + * Receive data segment of an iSCSI data-in PDU + * + * @v iscsi iSCSI session + * @v data Received data + * @v len Length of received data + * @v remaining Data remaining after this data + * @ret rc Return status code + */ +static int iscsi_rx_data_in ( struct iscsi_session *iscsi, + const void *data, size_t len, + size_t remaining ) { + struct iscsi_bhs_data_in *data_in = &iscsi->rx_bhs.data_in; + unsigned long offset; + + /* Copy data to data-in buffer */ + offset = ntohl ( data_in->offset ) + iscsi->rx_offset; + assert ( iscsi->command != NULL ); + assert ( iscsi->command->data_in ); + assert ( ( offset + len ) <= iscsi->command->data_in_len ); + copy_to_user ( iscsi->command->data_in, offset, data, len ); + + /* Wait for whole SCSI response to arrive */ + if ( remaining ) + return 0; + + /* Mark as completed if status is present */ + if ( data_in->flags & ISCSI_DATA_FLAG_STATUS ) { + assert ( ( offset + len ) == iscsi->command->data_in_len ); + assert ( data_in->flags & ISCSI_FLAG_FINAL ); + iscsi->command->status = data_in->status; + /* iSCSI cannot return an error status via a data-in */ + iscsi_scsi_done ( iscsi, 0 ); + } + + return 0; +} + +/** + * Receive data segment of an iSCSI R2T PDU + * + * @v iscsi iSCSI session + * @v data Received data + * @v len Length of received data + * @v remaining Data remaining after this data + * @ret rc Return status code + */ +static int iscsi_rx_r2t ( struct iscsi_session *iscsi, + const void *data __unused, size_t len __unused, + size_t remaining __unused ) { + struct iscsi_bhs_r2t *r2t = &iscsi->rx_bhs.r2t; + + /* Record transfer parameters and trigger first data-out */ + iscsi->ttt = ntohl ( r2t->ttt ); + iscsi->transfer_offset = ntohl ( r2t->offset ); + iscsi->transfer_len = ntohl ( r2t->len ); + iscsi_start_data_out ( iscsi, 0 ); + + return 0; +} + +/** + * Build iSCSI data-out BHS + * + * @v iscsi iSCSI session + * @v datasn Data sequence number within the transfer + * + */ +static void iscsi_start_data_out ( struct iscsi_session *iscsi, + unsigned int datasn ) { + struct iscsi_bhs_data_out *data_out = &iscsi->tx_bhs.data_out; + unsigned long offset; + unsigned long remaining; + unsigned long len; + + /* We always send 512-byte Data-Out PDUs; this removes the + * need to worry about the target's MaxRecvDataSegmentLength. + */ + offset = datasn * 512; + remaining = iscsi->transfer_len - offset; + len = remaining; + if ( len > 512 ) + len = 512; + + /* Construct BHS and initiate transmission */ + iscsi_start_tx ( iscsi ); + data_out->opcode = ISCSI_OPCODE_DATA_OUT; + if ( len == remaining ) + data_out->flags = ( ISCSI_FLAG_FINAL ); + ISCSI_SET_LENGTHS ( data_out->lengths, 0, len ); + data_out->lun = iscsi->lun; + data_out->itt = htonl ( iscsi->itt ); + data_out->ttt = htonl ( iscsi->ttt ); + data_out->expstatsn = htonl ( iscsi->statsn + 1 ); + data_out->datasn = htonl ( datasn ); + data_out->offset = htonl ( iscsi->transfer_offset + offset ); + DBGC ( iscsi, "iSCSI %p start data out DataSN %#x len %#lx\n", + iscsi, datasn, len ); +} + +/** + * Complete iSCSI data-out PDU transmission + * + * @v iscsi iSCSI session + * + */ +static void iscsi_data_out_done ( struct iscsi_session *iscsi ) { + struct iscsi_bhs_data_out *data_out = &iscsi->tx_bhs.data_out; + + /* If we haven't reached the end of the sequence, start + * sending the next data-out PDU. + */ + if ( ! ( data_out->flags & ISCSI_FLAG_FINAL ) ) + iscsi_start_data_out ( iscsi, ntohl ( data_out->datasn ) + 1 ); +} + +/** + * Send iSCSI data-out data segment + * + * @v iscsi iSCSI session + * @ret rc Return status code + */ +static int iscsi_tx_data_out ( struct iscsi_session *iscsi ) { + struct iscsi_bhs_data_out *data_out = &iscsi->tx_bhs.data_out; + struct io_buffer *iobuf; + unsigned long offset; + size_t len; + + offset = ntohl ( data_out->offset ); + len = ISCSI_DATA_LEN ( data_out->lengths ); + + assert ( iscsi->command != NULL ); + assert ( iscsi->command->data_out ); + assert ( ( offset + len ) <= iscsi->command->data_out_len ); + + iobuf = xfer_alloc_iob ( &iscsi->socket, len ); + if ( ! iobuf ) + return -ENOMEM; + + copy_from_user ( iob_put ( iobuf, len ), + iscsi->command->data_out, offset, len ); + + return xfer_deliver_iob ( &iscsi->socket, iobuf ); +} + +/**************************************************************************** + * + * iSCSI login + * + */ + +/** + * Build iSCSI login request strings + * + * @v iscsi iSCSI session + * + * These are the initial set of strings sent in the first login + * request PDU. We want the following settings: + * + * HeaderDigest=None + * DataDigest=None + * MaxConnections is irrelevant; we make only one connection anyway + * InitialR2T=Yes [1] + * ImmediateData is irrelevant; we never send immediate data + * MaxRecvDataSegmentLength=8192 (default; we don't care) [3] + * MaxBurstLength=262144 (default; we don't care) [3] + * FirstBurstLength=262144 (default; we don't care) + * DefaultTime2Wait=0 [2] + * DefaultTime2Retain=0 [2] + * MaxOutstandingR2T=1 + * DataPDUInOrder=Yes + * DataSequenceInOrder=Yes + * ErrorRecoveryLevel=0 + * + * [1] InitialR2T has an OR resolution function, so the target may + * force us to use it. We therefore simplify our logic by always + * using it. + * + * [2] These ensure that we can safely start a new task once we have + * reconnected after a failure, without having to manually tidy up + * after the old one. + * + * [3] We are quite happy to use the RFC-defined default values for + * these parameters, but some targets (notably OpenSolaris) + * incorrectly assume a default value of zero, so we explicitly + * specify the default values. + */ +static int iscsi_build_login_request_strings ( struct iscsi_session *iscsi, + void *data, size_t len ) { + unsigned int used = 0; + unsigned int i; + const char *auth_method; + + if ( iscsi->status & ISCSI_STATUS_STRINGS_SECURITY ) { + /* Default to allowing no authentication */ + auth_method = "None"; + /* If we have a credential to supply, permit CHAP */ + if ( iscsi->initiator_username ) + auth_method = "CHAP,None"; + /* If we have a credential to check, force CHAP */ + if ( iscsi->target_username ) + auth_method = "CHAP"; + used += ssnprintf ( data + used, len - used, + "InitiatorName=%s%c" + "TargetName=%s%c" + "SessionType=Normal%c" + "AuthMethod=%s%c", + iscsi_initiator_iqn(), 0, + iscsi->target_iqn, 0, 0, + auth_method, 0 ); + } + + if ( iscsi->status & ISCSI_STATUS_STRINGS_CHAP_ALGORITHM ) { + used += ssnprintf ( data + used, len - used, "CHAP_A=5%c", 0 ); + } + + if ( ( iscsi->status & ISCSI_STATUS_STRINGS_CHAP_RESPONSE ) ) { + assert ( iscsi->initiator_username != NULL ); + used += ssnprintf ( data + used, len - used, + "CHAP_N=%s%cCHAP_R=0x", + iscsi->initiator_username, 0 ); + for ( i = 0 ; i < iscsi->chap.response_len ; i++ ) { + used += ssnprintf ( data + used, len - used, "%02x", + iscsi->chap.response[i] ); + } + used += ssnprintf ( data + used, len - used, "%c", 0 ); + } + + if ( ( iscsi->status & ISCSI_STATUS_STRINGS_CHAP_CHALLENGE ) ) { + used += ssnprintf ( data + used, len - used, + "CHAP_I=%d%cCHAP_C=0x", + iscsi->chap_challenge[0], 0 ); + for ( i = 1 ; i < sizeof ( iscsi->chap_challenge ) ; i++ ) { + used += ssnprintf ( data + used, len - used, "%02x", + iscsi->chap_challenge[i] ); + } + used += ssnprintf ( data + used, len - used, "%c", 0 ); + } + + if ( iscsi->status & ISCSI_STATUS_STRINGS_OPERATIONAL ) { + used += ssnprintf ( data + used, len - used, + "HeaderDigest=None%c" + "DataDigest=None%c" + "InitialR2T=Yes%c" + "MaxRecvDataSegmentLength=8192%c" + "MaxBurstLength=262144%c" + "DefaultTime2Wait=0%c" + "DefaultTime2Retain=0%c" + "MaxOutstandingR2T=1%c" + "DataPDUInOrder=Yes%c" + "DataSequenceInOrder=Yes%c" + "ErrorRecoveryLevel=0%c", + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 ); + } + + return used; +} + +/** + * Build iSCSI login request BHS + * + * @v iscsi iSCSI session + */ +static void iscsi_start_login ( struct iscsi_session *iscsi ) { + struct iscsi_bhs_login_request *request = &iscsi->tx_bhs.login_request; + int len; + + /* Construct BHS and initiate transmission */ + iscsi_start_tx ( iscsi ); + request->opcode = ( ISCSI_OPCODE_LOGIN_REQUEST | + ISCSI_FLAG_IMMEDIATE ); + request->flags = ( ( iscsi->status & ISCSI_STATUS_PHASE_MASK ) | + ISCSI_LOGIN_FLAG_TRANSITION ); + /* version_max and version_min left as zero */ + len = iscsi_build_login_request_strings ( iscsi, NULL, 0 ); + ISCSI_SET_LENGTHS ( request->lengths, 0, len ); + request->isid_iana_en = htonl ( ISCSI_ISID_IANA | + IANA_EN_FEN_SYSTEMS ); + /* isid_iana_qual left as zero */ + request->tsih = htons ( iscsi->tsih ); + request->itt = htonl ( iscsi->itt ); + /* cid left as zero */ + request->cmdsn = htonl ( iscsi->cmdsn ); + request->expstatsn = htonl ( iscsi->statsn + 1 ); +} + +/** + * Complete iSCSI login request PDU transmission + * + * @v iscsi iSCSI session + * + */ +static void iscsi_login_request_done ( struct iscsi_session *iscsi ) { + + /* Clear any "strings to send" flags */ + iscsi->status &= ~ISCSI_STATUS_STRINGS_MASK; + + /* Free any dynamically allocated storage used for login */ + chap_finish ( &iscsi->chap ); +} + +/** + * Transmit data segment of an iSCSI login request PDU + * + * @v iscsi iSCSI session + * @ret rc Return status code + * + * For login requests, the data segment consists of the login strings. + */ +static int iscsi_tx_login_request ( struct iscsi_session *iscsi ) { + struct iscsi_bhs_login_request *request = &iscsi->tx_bhs.login_request; + struct io_buffer *iobuf; + size_t len; + + len = ISCSI_DATA_LEN ( request->lengths ); + iobuf = xfer_alloc_iob ( &iscsi->socket, len ); + if ( ! iobuf ) + return -ENOMEM; + iob_put ( iobuf, len ); + iscsi_build_login_request_strings ( iscsi, iobuf->data, len ); + return xfer_deliver_iob ( &iscsi->socket, iobuf ); +} + +/** + * Handle iSCSI TargetAddress text value + * + * @v iscsi iSCSI session + * @v value TargetAddress value + * @ret rc Return status code + */ +static int iscsi_handle_targetaddress_value ( struct iscsi_session *iscsi, + const char *value ) { + char *separator; + + DBGC ( iscsi, "iSCSI %p will redirect to %s\n", iscsi, value ); + + /* Replace target address */ + free ( iscsi->target_address ); + iscsi->target_address = strdup ( value ); + if ( ! iscsi->target_address ) + return -ENOMEM; + + /* Replace target port */ + iscsi->target_port = htons ( ISCSI_PORT ); + separator = strchr ( iscsi->target_address, ':' ); + if ( separator ) { + *separator = '\0'; + iscsi->target_port = strtoul ( ( separator + 1 ), NULL, 0 ); + } + + return 0; +} + +/** + * Handle iSCSI AuthMethod text value + * + * @v iscsi iSCSI session + * @v value AuthMethod value + * @ret rc Return status code + */ +static int iscsi_handle_authmethod_value ( struct iscsi_session *iscsi, + const char *value ) { + + /* If server requests CHAP, send the CHAP_A string */ + if ( strcmp ( value, "CHAP" ) == 0 ) { + DBGC ( iscsi, "iSCSI %p initiating CHAP authentication\n", + iscsi ); + iscsi->status |= ( ISCSI_STATUS_STRINGS_CHAP_ALGORITHM | + ISCSI_STATUS_AUTH_FORWARD_REQUIRED ); + } + + return 0; +} + +/** + * Handle iSCSI CHAP_A text value + * + * @v iscsi iSCSI session + * @v value CHAP_A value + * @ret rc Return status code + */ +static int iscsi_handle_chap_a_value ( struct iscsi_session *iscsi, + const char *value ) { + + /* We only ever offer "5" (i.e. MD5) as an algorithm, so if + * the server responds with anything else it is a protocol + * violation. + */ + if ( strcmp ( value, "5" ) != 0 ) { + DBGC ( iscsi, "iSCSI %p got invalid CHAP algorithm \"%s\"\n", + iscsi, value ); + return -EPROTO; + } + + return 0; +} + +/** + * Handle iSCSI CHAP_I text value + * + * @v iscsi iSCSI session + * @v value CHAP_I value + * @ret rc Return status code + */ +static int iscsi_handle_chap_i_value ( struct iscsi_session *iscsi, + const char *value ) { + unsigned int identifier; + char *endp; + int rc; + + /* The CHAP identifier is an integer value */ + identifier = strtoul ( value, &endp, 0 ); + if ( *endp != '\0' ) { + DBGC ( iscsi, "iSCSI %p saw invalid CHAP identifier \"%s\"\n", + iscsi, value ); + return -EPROTO; + } + + /* Prepare for CHAP with MD5 */ + chap_finish ( &iscsi->chap ); + if ( ( rc = chap_init ( &iscsi->chap, &md5_algorithm ) ) != 0 ) { + DBGC ( iscsi, "iSCSI %p could not initialise CHAP: %s\n", + iscsi, strerror ( rc ) ); + return rc; + } + + /* Identifier and secret are the first two components of the + * challenge. + */ + chap_set_identifier ( &iscsi->chap, identifier ); + if ( iscsi->initiator_password ) { + chap_update ( &iscsi->chap, iscsi->initiator_password, + strlen ( iscsi->initiator_password ) ); + } + + return 0; +} + +/** + * Handle iSCSI CHAP_C text value + * + * @v iscsi iSCSI session + * @v value CHAP_C value + * @ret rc Return status code + */ +static int iscsi_handle_chap_c_value ( struct iscsi_session *iscsi, + const char *value ) { + char buf[3]; + char *endp; + uint8_t byte; + unsigned int i; + + /* Check and strip leading "0x" */ + if ( ( value[0] != '0' ) || ( value[1] != 'x' ) ) { + DBGC ( iscsi, "iSCSI %p saw invalid CHAP challenge \"%s\"\n", + iscsi, value ); + return -EPROTO; + } + value += 2; + + /* Process challenge an octet at a time */ + for ( ; ( value[0] && value[1] ) ; value += 2 ) { + memcpy ( buf, value, 2 ); + buf[2] = 0; + byte = strtoul ( buf, &endp, 16 ); + if ( *endp != '\0' ) { + DBGC ( iscsi, "iSCSI %p saw invalid CHAP challenge " + "byte \"%s\"\n", iscsi, buf ); + return -EPROTO; + } + chap_update ( &iscsi->chap, &byte, sizeof ( byte ) ); + } + + /* Build CHAP response */ + DBGC ( iscsi, "iSCSI %p sending CHAP response\n", iscsi ); + chap_respond ( &iscsi->chap ); + iscsi->status |= ISCSI_STATUS_STRINGS_CHAP_RESPONSE; + + /* Send CHAP challenge, if applicable */ + if ( iscsi->target_username ) { + iscsi->status |= ISCSI_STATUS_STRINGS_CHAP_CHALLENGE; + /* Generate CHAP challenge data */ + for ( i = 0 ; i < sizeof ( iscsi->chap_challenge ) ; i++ ) { + iscsi->chap_challenge[i] = random(); + } + } + + return 0; +} + +/** + * Handle iSCSI CHAP_N text value + * + * @v iscsi iSCSI session + * @v value CHAP_N value + * @ret rc Return status code + */ +static int iscsi_handle_chap_n_value ( struct iscsi_session *iscsi, + const char *value ) { + + /* The target username isn't actually involved at any point in + * the authentication process; it merely serves to identify + * which password the target is using to generate the CHAP + * response. We unnecessarily verify that the username is as + * expected, in order to provide mildly helpful diagnostics if + * the target is supplying the wrong username/password + * combination. + */ + if ( iscsi->target_username && + ( strcmp ( iscsi->target_username, value ) != 0 ) ) { + DBGC ( iscsi, "iSCSI %p target username \"%s\" incorrect " + "(wanted \"%s\")\n", + iscsi, value, iscsi->target_username ); + return -EACCES; + } + + return 0; +} + +/** + * Handle iSCSI CHAP_R text value + * + * @v iscsi iSCSI session + * @v value CHAP_R value + * @ret rc Return status code + */ +static int iscsi_handle_chap_r_value ( struct iscsi_session *iscsi, + const char *value ) { + char buf[3]; + char *endp; + uint8_t byte; + unsigned int i; + int rc; + + /* Generate CHAP response for verification */ + chap_finish ( &iscsi->chap ); + if ( ( rc = chap_init ( &iscsi->chap, &md5_algorithm ) ) != 0 ) { + DBGC ( iscsi, "iSCSI %p could not initialise CHAP: %s\n", + iscsi, strerror ( rc ) ); + return rc; + } + chap_set_identifier ( &iscsi->chap, iscsi->chap_challenge[0] ); + if ( iscsi->target_password ) { + chap_update ( &iscsi->chap, iscsi->target_password, + strlen ( iscsi->target_password ) ); + } + chap_update ( &iscsi->chap, &iscsi->chap_challenge[1], + ( sizeof ( iscsi->chap_challenge ) - 1 ) ); + chap_respond ( &iscsi->chap ); + + /* Check and strip leading "0x" */ + if ( ( value[0] != '0' ) || ( value[1] != 'x' ) ) { + DBGC ( iscsi, "iSCSI %p saw invalid CHAP response \"%s\"\n", + iscsi, value ); + return -EPROTO; + } + value += 2; + + /* Check CHAP response length */ + if ( strlen ( value ) != ( 2 * iscsi->chap.response_len ) ) { + DBGC ( iscsi, "iSCSI %p invalid CHAP response length\n", + iscsi ); + return -EPROTO; + } + + /* Process response an octet at a time */ + for ( i = 0 ; ( value[0] && value[1] ) ; value += 2, i++ ) { + memcpy ( buf, value, 2 ); + buf[2] = 0; + byte = strtoul ( buf, &endp, 16 ); + if ( *endp != '\0' ) { + DBGC ( iscsi, "iSCSI %p saw invalid CHAP response " + "byte \"%s\"\n", iscsi, buf ); + return -EPROTO; + } + if ( byte != iscsi->chap.response[i] ) { + DBGC ( iscsi, "iSCSI %p saw incorrect CHAP " + "response\n", iscsi ); + return -EACCES; + } + } + assert ( i == iscsi->chap.response_len ); + + /* Mark session as authenticated */ + iscsi->status |= ISCSI_STATUS_AUTH_REVERSE_OK; + + return 0; +} + +/** An iSCSI text string that we want to handle */ +struct iscsi_string_type { + /** String key + * + * This is the portion up to and including the "=" sign, + * e.g. "InitiatorName=", "CHAP_A=", etc. + */ + const char *key; + /** Handle iSCSI string value + * + * @v iscsi iSCSI session + * @v value iSCSI string value + * @ret rc Return status code + */ + int ( * handle ) ( struct iscsi_session *iscsi, const char *value ); +}; + +/** iSCSI text strings that we want to handle */ +static struct iscsi_string_type iscsi_string_types[] = { + { "TargetAddress=", iscsi_handle_targetaddress_value }, + { "AuthMethod=", iscsi_handle_authmethod_value }, + { "CHAP_A=", iscsi_handle_chap_a_value }, + { "CHAP_I=", iscsi_handle_chap_i_value }, + { "CHAP_C=", iscsi_handle_chap_c_value }, + { "CHAP_N=", iscsi_handle_chap_n_value }, + { "CHAP_R=", iscsi_handle_chap_r_value }, + { NULL, NULL } +}; + +/** + * Handle iSCSI string + * + * @v iscsi iSCSI session + * @v string iSCSI string (in "key=value" format) + * @ret rc Return status code + */ +static int iscsi_handle_string ( struct iscsi_session *iscsi, + const char *string ) { + struct iscsi_string_type *type; + size_t key_len; + int rc; + + for ( type = iscsi_string_types ; type->key ; type++ ) { + key_len = strlen ( type->key ); + if ( strncmp ( string, type->key, key_len ) != 0 ) + continue; + DBGC ( iscsi, "iSCSI %p handling %s\n", iscsi, string ); + if ( ( rc = type->handle ( iscsi, + ( string + key_len ) ) ) != 0 ) { + DBGC ( iscsi, "iSCSI %p could not handle %s: %s\n", + iscsi, string, strerror ( rc ) ); + return rc; + } + return 0; + } + DBGC ( iscsi, "iSCSI %p ignoring %s\n", iscsi, string ); + return 0; +} + +/** + * Handle iSCSI strings + * + * @v iscsi iSCSI session + * @v string iSCSI string buffer + * @v len Length of string buffer + * @ret rc Return status code + */ +static int iscsi_handle_strings ( struct iscsi_session *iscsi, + const char *strings, size_t len ) { + size_t string_len; + int rc; + + /* Handle each string in turn, taking care not to overrun the + * data buffer in case of badly-terminated data. + */ + while ( 1 ) { + string_len = ( strnlen ( strings, len ) + 1 ); + if ( string_len > len ) + break; + if ( ( rc = iscsi_handle_string ( iscsi, strings ) ) != 0 ) + return rc; + strings += string_len; + len -= string_len; + } + return 0; +} + +/** + * Receive PDU data into buffer + * + * @v iscsi iSCSI session + * @v data Data to receive + * @v len Length of data + * @ret rc Return status code + * + * This can be used when the RX PDU type handler wishes to buffer up + * all received data and process the PDU as a single unit. The caller + * is repsonsible for calling iscsi_rx_buffered_data_done() after + * processing the data. + */ +static int iscsi_rx_buffered_data ( struct iscsi_session *iscsi, + const void *data, size_t len ) { + + /* Allocate buffer on first call */ + if ( ! iscsi->rx_buffer ) { + iscsi->rx_buffer = malloc ( iscsi->rx_len ); + if ( ! iscsi->rx_buffer ) + return -ENOMEM; + } + + /* Copy data to buffer */ + assert ( ( iscsi->rx_offset + len ) <= iscsi->rx_len ); + memcpy ( ( iscsi->rx_buffer + iscsi->rx_offset ), data, len ); + + return 0; +} + +/** + * Convert iSCSI response status to return status code + * + * @v status_class iSCSI status class + * @v status_detail iSCSI status detail + * @ret rc Return status code + */ +static int iscsi_status_to_rc ( unsigned int status_class, + unsigned int status_detail ) { + switch ( status_class ) { + case ISCSI_STATUS_INITIATOR_ERROR : + switch ( status_detail ) { + case ISCSI_STATUS_INITIATOR_ERROR_AUTHENTICATION : + return -EACCES; + case ISCSI_STATUS_INITIATOR_ERROR_AUTHORISATION : + return -EPERM; + case ISCSI_STATUS_INITIATOR_ERROR_NOT_FOUND : + case ISCSI_STATUS_INITIATOR_ERROR_REMOVED : + return -ENODEV; + default : + return -ENOTSUP; + } + case ISCSI_STATUS_TARGET_ERROR : + return -EIO; + default : + return -EINVAL; + } +} + +/** + * Receive data segment of an iSCSI login response PDU + * + * @v iscsi iSCSI session + * @v data Received data + * @v len Length of received data + * @v remaining Data remaining after this data + * @ret rc Return status code + */ +static int iscsi_rx_login_response ( struct iscsi_session *iscsi, + const void *data, size_t len, + size_t remaining ) { + struct iscsi_bhs_login_response *response + = &iscsi->rx_bhs.login_response; + int rc; + + /* Buffer up the PDU data */ + if ( ( rc = iscsi_rx_buffered_data ( iscsi, data, len ) ) != 0 ) { + DBGC ( iscsi, "iSCSI %p could not buffer login response: %s\n", + iscsi, strerror ( rc ) ); + return rc; + } + if ( remaining ) + return 0; + + /* Process string data and discard string buffer */ + if ( ( rc = iscsi_handle_strings ( iscsi, iscsi->rx_buffer, + iscsi->rx_len ) ) != 0 ) + return rc; + iscsi_rx_buffered_data_done ( iscsi ); + + /* Check for login redirection */ + if ( response->status_class == ISCSI_STATUS_REDIRECT ) { + DBGC ( iscsi, "iSCSI %p redirecting to new server\n", iscsi ); + iscsi_close_connection ( iscsi, 0 ); + if ( ( rc = iscsi_open_connection ( iscsi ) ) != 0 ) { + DBGC ( iscsi, "iSCSI %p could not redirect: %s\n ", + iscsi, strerror ( rc ) ); + return rc; + } + return 0; + } + + /* Check for fatal errors */ + if ( response->status_class != 0 ) { + DBGC ( iscsi, "iSCSI login failure: class %02x detail %02x\n", + response->status_class, response->status_detail ); + rc = iscsi_status_to_rc ( response->status_class, + response->status_detail ); + iscsi->instant_rc = rc; + return rc; + } + + /* Handle login transitions */ + if ( response->flags & ISCSI_LOGIN_FLAG_TRANSITION ) { + iscsi->status &= ~( ISCSI_STATUS_PHASE_MASK | + ISCSI_STATUS_STRINGS_MASK ); + switch ( response->flags & ISCSI_LOGIN_NSG_MASK ) { + case ISCSI_LOGIN_NSG_OPERATIONAL_NEGOTIATION: + iscsi->status |= + ( ISCSI_STATUS_OPERATIONAL_NEGOTIATION_PHASE | + ISCSI_STATUS_STRINGS_OPERATIONAL ); + break; + case ISCSI_LOGIN_NSG_FULL_FEATURE_PHASE: + iscsi->status |= ISCSI_STATUS_FULL_FEATURE_PHASE; + break; + default: + DBGC ( iscsi, "iSCSI %p got invalid response flags " + "%02x\n", iscsi, response->flags ); + return -EIO; + } + } + + /* Send next login request PDU if we haven't reached the full + * feature phase yet. + */ + if ( ( iscsi->status & ISCSI_STATUS_PHASE_MASK ) != + ISCSI_STATUS_FULL_FEATURE_PHASE ) { + iscsi_start_login ( iscsi ); + return 0; + } + + /* Check that target authentication was successful (if required) */ + if ( ( iscsi->status & ISCSI_STATUS_AUTH_REVERSE_REQUIRED ) && + ! ( iscsi->status & ISCSI_STATUS_AUTH_REVERSE_OK ) ) { + DBGC ( iscsi, "iSCSI %p nefarious target tried to bypass " + "authentication\n", iscsi ); + return -EPROTO; + } + + /* Reset retry count */ + iscsi->retry_count = 0; + + /* Record TSIH for future reference */ + iscsi->tsih = ntohl ( response->tsih ); + + /* Send the actual SCSI command */ + iscsi_start_command ( iscsi ); + + return 0; +} + +/**************************************************************************** + * + * iSCSI to socket interface + * + */ + +/** + * Start up a new TX PDU + * + * @v iscsi iSCSI session + * + * This initiates the process of sending a new PDU. Only one PDU may + * be in transit at any one time. + */ +static void iscsi_start_tx ( struct iscsi_session *iscsi ) { + assert ( iscsi->tx_state == ISCSI_TX_IDLE ); + + /* Initialise TX BHS */ + memset ( &iscsi->tx_bhs, 0, sizeof ( iscsi->tx_bhs ) ); + + /* Flag TX engine to start transmitting */ + iscsi->tx_state = ISCSI_TX_BHS; +} + +/** + * Transmit nothing + * + * @v iscsi iSCSI session + * @ret rc Return status code + */ +static int iscsi_tx_nothing ( struct iscsi_session *iscsi __unused ) { + return 0; +} + +/** + * Transmit basic header segment of an iSCSI PDU + * + * @v iscsi iSCSI session + * @ret rc Return status code + */ +static int iscsi_tx_bhs ( struct iscsi_session *iscsi ) { + return xfer_deliver_raw ( &iscsi->socket, &iscsi->tx_bhs, + sizeof ( iscsi->tx_bhs ) ); +} + +/** + * Transmit data segment of an iSCSI PDU + * + * @v iscsi iSCSI session + * @ret rc Return status code + * + * Handle transmission of part of a PDU data segment. iscsi::tx_bhs + * will be valid when this is called. + */ +static int iscsi_tx_data ( struct iscsi_session *iscsi ) { + struct iscsi_bhs_common *common = &iscsi->tx_bhs.common; + + switch ( common->opcode & ISCSI_OPCODE_MASK ) { + case ISCSI_OPCODE_DATA_OUT: + return iscsi_tx_data_out ( iscsi ); + case ISCSI_OPCODE_LOGIN_REQUEST: + return iscsi_tx_login_request ( iscsi ); + default: + /* Nothing to send in other states */ + return 0; + } +} + +/** + * Transmit data padding of an iSCSI PDU + * + * @v iscsi iSCSI session + * @ret rc Return status code + * + * Handle transmission of any data padding in a PDU data segment. + * iscsi::tx_bhs will be valid when this is called. + */ +static int iscsi_tx_data_padding ( struct iscsi_session *iscsi ) { + static const char pad[] = { '\0', '\0', '\0' }; + struct iscsi_bhs_common *common = &iscsi->tx_bhs.common; + size_t pad_len; + + pad_len = ISCSI_DATA_PAD_LEN ( common->lengths ); + if ( ! pad_len ) + return 0; + + return xfer_deliver_raw ( &iscsi->socket, pad, pad_len ); +} + +/** + * Complete iSCSI PDU transmission + * + * @v iscsi iSCSI session + * + * Called when a PDU has been completely transmitted and the TX state + * machine is about to enter the idle state. iscsi::tx_bhs will be + * valid for the just-completed PDU when this is called. + */ +static void iscsi_tx_done ( struct iscsi_session *iscsi ) { + struct iscsi_bhs_common *common = &iscsi->tx_bhs.common; + + switch ( common->opcode & ISCSI_OPCODE_MASK ) { + case ISCSI_OPCODE_DATA_OUT: + iscsi_data_out_done ( iscsi ); + case ISCSI_OPCODE_LOGIN_REQUEST: + iscsi_login_request_done ( iscsi ); + default: + /* No action */ + break; + } +} + +/** + * Transmit iSCSI PDU + * + * @v iscsi iSCSI session + * @v buf Temporary data buffer + * @v len Length of temporary data buffer + * + * Constructs data to be sent for the current TX state + */ +static void iscsi_tx_step ( struct process *process ) { + struct iscsi_session *iscsi = + container_of ( process, struct iscsi_session, process ); + struct iscsi_bhs_common *common = &iscsi->tx_bhs.common; + int ( * tx ) ( struct iscsi_session *iscsi ); + enum iscsi_tx_state next_state; + size_t tx_len; + int rc; + + /* Select fragment to transmit */ + while ( 1 ) { + switch ( iscsi->tx_state ) { + case ISCSI_TX_IDLE: + /* Stop processing */ + return; + case ISCSI_TX_BHS: + tx = iscsi_tx_bhs; + tx_len = sizeof ( iscsi->tx_bhs ); + next_state = ISCSI_TX_AHS; + break; + case ISCSI_TX_AHS: + tx = iscsi_tx_nothing; + tx_len = 0; + next_state = ISCSI_TX_DATA; + break; + case ISCSI_TX_DATA: + tx = iscsi_tx_data; + tx_len = ISCSI_DATA_LEN ( common->lengths ); + next_state = ISCSI_TX_DATA_PADDING; + break; + case ISCSI_TX_DATA_PADDING: + tx = iscsi_tx_data_padding; + tx_len = ISCSI_DATA_PAD_LEN ( common->lengths ); + next_state = ISCSI_TX_IDLE; + break; + default: + assert ( 0 ); + return; + } + + /* Check for window availability, if needed */ + if ( tx_len && ( xfer_window ( &iscsi->socket ) == 0 ) ) { + /* Cannot transmit at this point; stop processing */ + return; + } + + /* Transmit data */ + if ( ( rc = tx ( iscsi ) ) != 0 ) { + DBGC ( iscsi, "iSCSI %p could not transmit: %s\n", + iscsi, strerror ( rc ) ); + return; + } + + /* Move to next state */ + iscsi->tx_state = next_state; + if ( next_state == ISCSI_TX_IDLE ) + iscsi_tx_done ( iscsi ); + } +} + +/** + * Receive basic header segment of an iSCSI PDU + * + * @v iscsi iSCSI session + * @v data Received data + * @v len Length of received data + * @v remaining Data remaining after this data + * @ret rc Return status code + * + * This fills in iscsi::rx_bhs with the data from the BHS portion of + * the received PDU. + */ +static int iscsi_rx_bhs ( struct iscsi_session *iscsi, const void *data, + size_t len, size_t remaining __unused ) { + memcpy ( &iscsi->rx_bhs.bytes[iscsi->rx_offset], data, len ); + if ( ( iscsi->rx_offset + len ) >= sizeof ( iscsi->rx_bhs ) ) { + DBGC2 ( iscsi, "iSCSI %p received PDU opcode %#x len %#x\n", + iscsi, iscsi->rx_bhs.common.opcode, + ISCSI_DATA_LEN ( iscsi->rx_bhs.common.lengths ) ); + } + return 0; +} + +/** + * Discard portion of an iSCSI PDU. + * + * @v iscsi iSCSI session + * @v data Received data + * @v len Length of received data + * @v remaining Data remaining after this data + * @ret rc Return status code + * + * This discards data from a portion of a received PDU. + */ +static int iscsi_rx_discard ( struct iscsi_session *iscsi __unused, + const void *data __unused, size_t len __unused, + size_t remaining __unused ) { + /* Do nothing */ + return 0; +} + +/** + * Receive data segment of an iSCSI PDU + * + * @v iscsi iSCSI session + * @v data Received data + * @v len Length of received data + * @v remaining Data remaining after this data + * @ret rc Return status code + * + * Handle processing of part of a PDU data segment. iscsi::rx_bhs + * will be valid when this is called. + */ +static int iscsi_rx_data ( struct iscsi_session *iscsi, const void *data, + size_t len, size_t remaining ) { + struct iscsi_bhs_common_response *response + = &iscsi->rx_bhs.common_response; + + /* Update cmdsn and statsn */ + iscsi->cmdsn = ntohl ( response->expcmdsn ); + iscsi->statsn = ntohl ( response->statsn ); + + switch ( response->opcode & ISCSI_OPCODE_MASK ) { + case ISCSI_OPCODE_LOGIN_RESPONSE: + return iscsi_rx_login_response ( iscsi, data, len, remaining ); + case ISCSI_OPCODE_SCSI_RESPONSE: + return iscsi_rx_scsi_response ( iscsi, data, len, remaining ); + case ISCSI_OPCODE_DATA_IN: + return iscsi_rx_data_in ( iscsi, data, len, remaining ); + case ISCSI_OPCODE_R2T: + return iscsi_rx_r2t ( iscsi, data, len, remaining ); + default: + if ( remaining ) + return 0; + DBGC ( iscsi, "iSCSI %p unknown opcode %02x\n", iscsi, + response->opcode ); + return -ENOTSUP; + } +} + +/** + * Receive new data + * + * @v socket Transport layer interface + * @v data Received data + * @v len Length of received data + * @ret rc Return status code + * + * This handles received PDUs. The receive strategy is to fill in + * iscsi::rx_bhs with the contents of the BHS portion of the PDU, + * throw away any AHS portion, and then process each part of the data + * portion as it arrives. The data processing routine therefore + * always has a full copy of the BHS available, even for portions of + * the data in different packets to the BHS. + */ +static int iscsi_socket_deliver_raw ( struct xfer_interface *socket, + const void *data, size_t len ) { + struct iscsi_session *iscsi = + container_of ( socket, struct iscsi_session, socket ); + struct iscsi_bhs_common *common = &iscsi->rx_bhs.common; + int ( * rx ) ( struct iscsi_session *iscsi, const void *data, + size_t len, size_t remaining ); + enum iscsi_rx_state next_state; + size_t frag_len; + size_t remaining; + int rc; + + while ( 1 ) { + switch ( iscsi->rx_state ) { + case ISCSI_RX_BHS: + rx = iscsi_rx_bhs; + iscsi->rx_len = sizeof ( iscsi->rx_bhs ); + next_state = ISCSI_RX_AHS; + break; + case ISCSI_RX_AHS: + rx = iscsi_rx_discard; + iscsi->rx_len = 4 * ISCSI_AHS_LEN ( common->lengths ); + next_state = ISCSI_RX_DATA; + break; + case ISCSI_RX_DATA: + rx = iscsi_rx_data; + iscsi->rx_len = ISCSI_DATA_LEN ( common->lengths ); + next_state = ISCSI_RX_DATA_PADDING; + break; + case ISCSI_RX_DATA_PADDING: + rx = iscsi_rx_discard; + iscsi->rx_len = ISCSI_DATA_PAD_LEN ( common->lengths ); + next_state = ISCSI_RX_BHS; + break; + default: + assert ( 0 ); + return -EINVAL; + } + + frag_len = iscsi->rx_len - iscsi->rx_offset; + if ( frag_len > len ) + frag_len = len; + remaining = iscsi->rx_len - iscsi->rx_offset - frag_len; + if ( ( rc = rx ( iscsi, data, frag_len, remaining ) ) != 0 ) { + DBGC ( iscsi, "iSCSI %p could not process received " + "data: %s\n", iscsi, strerror ( rc ) ); + iscsi_close_connection ( iscsi, rc ); + iscsi_scsi_done ( iscsi, rc ); + return rc; + } + + iscsi->rx_offset += frag_len; + data += frag_len; + len -= frag_len; + + /* If all the data for this state has not yet been + * received, stay in this state for now. + */ + if ( iscsi->rx_offset != iscsi->rx_len ) + return 0; + + iscsi->rx_state = next_state; + iscsi->rx_offset = 0; + } + + return 0; +} + +/** + * Handle stream connection closure + * + * @v socket Transport layer interface + * @v rc Reason for close + * + */ +static void iscsi_socket_close ( struct xfer_interface *socket, int rc ) { + struct iscsi_session *iscsi = + container_of ( socket, struct iscsi_session, socket ); + + /* Even a graceful close counts as an error for iSCSI */ + if ( ! rc ) + rc = -ECONNRESET; + + /* Close session cleanly */ + iscsi_close_connection ( iscsi, rc ); + + /* Retry connection if within the retry limit, otherwise fail */ + if ( ++iscsi->retry_count <= ISCSI_MAX_RETRIES ) { + DBGC ( iscsi, "iSCSI %p retrying connection (retry #%d)\n", + iscsi, iscsi->retry_count ); + if ( ( rc = iscsi_open_connection ( iscsi ) ) != 0 ) { + DBGC ( iscsi, "iSCSI %p could not reconnect: %s\n", + iscsi, strerror ( rc ) ); + iscsi_scsi_done ( iscsi, rc ); + } + } else { + DBGC ( iscsi, "iSCSI %p retry count exceeded\n", iscsi ); + iscsi->instant_rc = rc; + iscsi_scsi_done ( iscsi, rc ); + } +} + +/** + * Handle redirection event + * + * @v socket Transport layer interface + * @v type Location type + * @v args Remaining arguments depend upon location type + * @ret rc Return status code + */ +static int iscsi_vredirect ( struct xfer_interface *socket, int type, + va_list args ) { + struct iscsi_session *iscsi = + container_of ( socket, struct iscsi_session, socket ); + va_list tmp; + struct sockaddr *peer; + + /* Intercept redirects to a LOCATION_SOCKET and record the IP + * address for the iBFT. This is a bit of a hack, but avoids + * inventing an ioctl()-style call to retrieve the socket + * address from a data-xfer interface. + */ + if ( type == LOCATION_SOCKET ) { + va_copy ( tmp, args ); + ( void ) va_arg ( tmp, int ); /* Discard "semantics" */ + peer = va_arg ( tmp, struct sockaddr * ); + memcpy ( &iscsi->target_sockaddr, peer, + sizeof ( iscsi->target_sockaddr ) ); + va_end ( tmp ); + } + + return xfer_vreopen ( socket, type, args ); +} + + +/** iSCSI socket operations */ +static struct xfer_interface_operations iscsi_socket_operations = { + .close = iscsi_socket_close, + .vredirect = iscsi_vredirect, + .window = unlimited_xfer_window, + .alloc_iob = default_xfer_alloc_iob, + .deliver_iob = xfer_deliver_as_raw, + .deliver_raw = iscsi_socket_deliver_raw, +}; + + +/**************************************************************************** + * + * iSCSI command issuing + * + */ + +/** + * Issue SCSI command + * + * @v scsi SCSI device + * @v command SCSI command + * @ret rc Return status code + */ +static int iscsi_command ( struct scsi_device *scsi, + struct scsi_command *command ) { + struct iscsi_session *iscsi = + container_of ( scsi->backend, struct iscsi_session, refcnt ); + int rc; + + /* Abort immediately if we have a recorded permanent failure */ + if ( iscsi->instant_rc ) + return iscsi->instant_rc; + + /* Record SCSI command */ + iscsi->command = command; + + /* Issue command or open connection as appropriate */ + if ( iscsi->status ) { + iscsi_start_command ( iscsi ); + } else { + if ( ( rc = iscsi_open_connection ( iscsi ) ) != 0 ) { + iscsi->command = NULL; + return rc; + } + } + + return 0; +} + +/** + * Shut down iSCSI interface + * + * @v scsi SCSI device + */ +void iscsi_detach ( struct scsi_device *scsi ) { + struct iscsi_session *iscsi = + container_of ( scsi->backend, struct iscsi_session, refcnt ); + + xfer_nullify ( &iscsi->socket ); + iscsi_close_connection ( iscsi, 0 ); + process_del ( &iscsi->process ); + scsi->command = scsi_detached_command; + ref_put ( scsi->backend ); + scsi->backend = NULL; +} + +/**************************************************************************** + * + * Instantiator + * + */ + +/** iSCSI root path components (as per RFC4173) */ +enum iscsi_root_path_component { + RP_LITERAL = 0, + RP_SERVERNAME, + RP_PROTOCOL, + RP_PORT, + RP_LUN, + RP_TARGETNAME, + NUM_RP_COMPONENTS +}; + +/** + * Parse iSCSI root path + * + * @v iscsi iSCSI session + * @v root_path iSCSI root path (as per RFC4173) + * @ret rc Return status code + */ +static int iscsi_parse_root_path ( struct iscsi_session *iscsi, + const char *root_path ) { + char rp_copy[ strlen ( root_path ) + 1 ]; + char *rp_comp[NUM_RP_COMPONENTS]; + char *rp = rp_copy; + int i = 0; + int rc; + + /* Split root path into component parts */ + strcpy ( rp_copy, root_path ); + while ( 1 ) { + rp_comp[i++] = rp; + if ( i == NUM_RP_COMPONENTS ) + break; + for ( ; *rp != ':' ; rp++ ) { + if ( ! *rp ) { + DBGC ( iscsi, "iSCSI %p root path \"%s\" " + "too short\n", iscsi, root_path ); + return -EINVAL; + } + } + *(rp++) = '\0'; + } + + /* Use root path components to configure iSCSI session */ + iscsi->target_address = strdup ( rp_comp[RP_SERVERNAME] ); + if ( ! iscsi->target_address ) + return -ENOMEM; + iscsi->target_port = strtoul ( rp_comp[RP_PORT], NULL, 10 ); + if ( ! iscsi->target_port ) + iscsi->target_port = ISCSI_PORT; + if ( ( rc = scsi_parse_lun ( rp_comp[RP_LUN], &iscsi->lun ) ) != 0 ) { + DBGC ( iscsi, "iSCSI %p invalid LUN \"%s\"\n", + iscsi, rp_comp[RP_LUN] ); + return rc; + } + iscsi->target_iqn = strdup ( rp_comp[RP_TARGETNAME] ); + if ( ! iscsi->target_iqn ) + return -ENOMEM; + + return 0; +} + +/** + * Set iSCSI authentication details + * + * @v iscsi iSCSI session + * @v initiator_username Initiator username, if any + * @v initiator_password Initiator password, if any + * @v target_username Target username, if any + * @v target_password Target password, if any + * @ret rc Return status code + */ +static int iscsi_set_auth ( struct iscsi_session *iscsi, + const char *initiator_username, + const char *initiator_password, + const char *target_username, + const char *target_password ) { + + /* Check for initiator or target credentials */ + if ( initiator_username || initiator_password || + target_username || target_password ) { + + /* We must have at least an initiator username+password */ + if ( ! ( initiator_username && initiator_password ) ) + goto invalid_auth; + + /* Store initiator credentials */ + iscsi->initiator_username = strdup ( initiator_username ); + if ( ! iscsi->initiator_username ) + return -ENOMEM; + iscsi->initiator_password = strdup ( initiator_password ); + if ( ! iscsi->initiator_password ) + return -ENOMEM; + + /* Check for target credentials */ + if ( target_username || target_password ) { + + /* We must have target username+password */ + if ( ! ( target_username && target_password ) ) + goto invalid_auth; + + /* Store target credentials */ + iscsi->target_username = strdup ( target_username ); + if ( ! iscsi->target_username ) + return -ENOMEM; + iscsi->target_password = strdup ( target_password ); + if ( ! iscsi->target_password ) + return -ENOMEM; + } + } + + return 0; + + invalid_auth: + DBGC ( iscsi, "iSCSI %p invalid credentials: initiator " + "%sname,%spw, target %sname,%spw\n", iscsi, + ( initiator_username ? "" : "no " ), + ( initiator_password ? "" : "no " ), + ( target_username ? "" : "no " ), + ( target_password ? "" : "no " ) ); + return -EINVAL; +} + +/** + * Attach iSCSI interface + * + * @v scsi SCSI device + * @v root_path iSCSI root path (as per RFC4173) + * @ret rc Return status code + */ +int iscsi_attach ( struct scsi_device *scsi, const char *root_path ) { + struct iscsi_session *iscsi; + int rc; + + /* Allocate and initialise structure */ + iscsi = zalloc ( sizeof ( *iscsi ) ); + if ( ! iscsi ) + return -ENOMEM; + iscsi->refcnt.free = iscsi_free; + xfer_init ( &iscsi->socket, &iscsi_socket_operations, &iscsi->refcnt ); + process_init ( &iscsi->process, iscsi_tx_step, &iscsi->refcnt ); + + /* Parse root path */ + if ( ( rc = iscsi_parse_root_path ( iscsi, root_path ) ) != 0 ) + goto err; + /* Set fields not specified by root path */ + if ( ( rc = iscsi_set_auth ( iscsi, + iscsi_initiator_username, + iscsi_initiator_password, + iscsi_target_username, + iscsi_target_password ) ) != 0 ) + goto err; + + /* Sanity checks */ + if ( ! iscsi->target_address ) { + DBGC ( iscsi, "iSCSI %p does not yet support discovery\n", + iscsi ); + rc = -ENOTSUP; + goto err; + } + if ( ! iscsi->target_iqn ) { + DBGC ( iscsi, "iSCSI %p no target address supplied in %s\n", + iscsi, root_path ); + rc = -EINVAL; + goto err; + } + + /* Attach parent interface, mortalise self, and return */ + scsi->backend = ref_get ( &iscsi->refcnt ); + scsi->command = iscsi_command; + ref_put ( &iscsi->refcnt ); + return 0; + + err: + ref_put ( &iscsi->refcnt ); + return rc; +} + +/**************************************************************************** + * + * Settings + * + */ + +/** iSCSI initiator IQN setting */ +struct setting initiator_iqn_setting __setting = { + .name = "initiator-iqn", + .description = "iSCSI initiator name", + .tag = DHCP_ISCSI_INITIATOR_IQN, + .type = &setting_type_string, +}; + +/** iSCSI reverse username setting */ +struct setting reverse_username_setting __setting = { + .name = "reverse-username", + .description = "Reverse user name", + .tag = DHCP_EB_REVERSE_USERNAME, + .type = &setting_type_string, +}; + +/** iSCSI reverse password setting */ +struct setting reverse_password_setting __setting = { + .name = "reverse-password", + .description = "Reverse password", + .tag = DHCP_EB_REVERSE_PASSWORD, + .type = &setting_type_string, +}; + +/** An iSCSI string setting */ +struct iscsi_string_setting { + /** Setting */ + struct setting *setting; + /** String to update */ + char **string; + /** String prefix */ + const char *prefix; +}; + +/** iSCSI string settings */ +static struct iscsi_string_setting iscsi_string_settings[] = { + { + .setting = &initiator_iqn_setting, + .string = &iscsi_explicit_initiator_iqn, + .prefix = "", + }, + { + .setting = &username_setting, + .string = &iscsi_initiator_username, + .prefix = "", + }, + { + .setting = &password_setting, + .string = &iscsi_initiator_password, + .prefix = "", + }, + { + .setting = &reverse_username_setting, + .string = &iscsi_target_username, + .prefix = "", + }, + { + .setting = &reverse_password_setting, + .string = &iscsi_target_password, + .prefix = "", + }, + { + .setting = &hostname_setting, + .string = &iscsi_default_initiator_iqn, + .prefix = "iqn.2000-01.org.etherboot:", + }, +}; + +/** + * Apply iSCSI setting + * + * @v setting iSCSI string setting + * @ret rc Return status code + */ +static int apply_iscsi_string_setting ( struct iscsi_string_setting *setting ){ + size_t prefix_len; + int setting_len; + size_t len; + int check_len; + char *p; + + /* Free old string */ + free ( *setting->string ); + *setting->string = NULL; + + /* Allocate new string */ + prefix_len = strlen ( setting->prefix ); + setting_len = fetch_setting_len ( NULL, setting->setting ); + if ( setting_len < 0 ) { + /* Missing settings are not errors; leave strings as NULL */ + return 0; + } + len = ( prefix_len + setting_len + 1 ); + p = *setting->string = malloc ( len ); + if ( ! p ) + return -ENOMEM; + + /* Fill new string */ + strcpy ( p, setting->prefix ); + check_len = fetch_string_setting ( NULL, setting->setting, + ( p + prefix_len ), + ( len - prefix_len ) ); + assert ( check_len == setting_len ); + + return 0; +} + +/** + * Apply iSCSI settings + * + * @ret rc Return status code + */ +static int apply_iscsi_settings ( void ) { + struct iscsi_string_setting *setting; + unsigned int i; + int rc; + + for ( i = 0 ; i < ( sizeof ( iscsi_string_settings ) / + sizeof ( iscsi_string_settings[0] ) ) ; i++ ) { + setting = &iscsi_string_settings[i]; + if ( ( rc = apply_iscsi_string_setting ( setting ) ) != 0 ) { + DBG ( "iSCSI could not apply setting %s\n", + setting->setting->name ); + return rc; + } + } + + return 0; +} + +/** iSCSI settings applicator */ +struct settings_applicator iscsi_settings_applicator __settings_applicator = { + .apply = apply_iscsi_settings, +}; + +/**************************************************************************** + * + * Initiator name + * + */ + +/** + * Get iSCSI initiator IQN + * + * @v iscsi iSCSI session + * @ret rc Return status code + */ +const char * iscsi_initiator_iqn ( void ) { + + if ( iscsi_explicit_initiator_iqn ) + return iscsi_explicit_initiator_iqn; + if ( iscsi_default_initiator_iqn ) + return iscsi_default_initiator_iqn; + return "iqn.2000-09.org.etherboot:UNKNOWN"; +} |