LXR linux/drivers/target/target_core_fabric

   1/*******************************************************************************
   2 * Filename:  target_core_fabric_lib.c
   3 *
   4 * This file contains generic high level protocol identifier and PR
   5 * handlers for TCM fabric modules
   6 *
   7 * (c) Copyright 2010-2013 Datera, Inc.
   8 *
   9 * Nicholas A. Bellinger <nab@linux-iscsi.org>
  10 *
  11 * This program is free software; you can redistribute it and/or modify
  12 * it under the terms of the GNU General Public License as published by
  13 * the Free Software Foundation; either version 2 of the License, or
  14 * (at your option) any later version.
  15 *
  16 * This program is distributed in the hope that it will be useful,
  17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 * GNU General Public License for more details.
  20 *
  21 * You should have received a copy of the GNU General Public License
  22 * along with this program; if not, write to the Free Software
  23 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  24 *
  25 ******************************************************************************/
  26
  27/*
  28 * See SPC4, section 7.5 "Protocol specific parameters" for details
  29 * on the formats implemented in this file.
  30 */
  31
  32#include <linux/kernel.h>
  33#include <linux/string.h>
  34#include <linux/ctype.h>
  35#include <linux/spinlock.h>
  36#include <linux/export.h>
  37
  38#include <scsi/scsi_proto.h>
  39
  40#include <target/target_core_base.h>
  41#include <target/target_core_fabric.h>
  42
  43#include "target_core_internal.h"
  44#include "target_core_pr.h"
  45
  46
  47static int sas_get_pr_transport_id(
  48        struct se_node_acl *nacl,
  49        int *format_code,
  50        unsigned char *buf)
  51{
  52        int ret;
  53
  54        /* Skip over 'naa. prefix */
  55        ret = hex2bin(&buf[4], &nacl->initiatorname[4], 8);
  56        if (ret) {
  57                pr_debug("%s: invalid hex string\n", __func__);
  58                return ret;
  59        }
  60
  61        return 24;
  62}
  63
  64static int fc_get_pr_transport_id(
  65        struct se_node_acl *se_nacl,
  66        int *format_code,
  67        unsigned char *buf)
  68{
  69        unsigned char *ptr;
  70        int i, ret;
  71        u32 off = 8;
  72
  73        /*
  74         * We convert the ASCII formatted N Port name into a binary
  75         * encoded TransportID.
  76         */
  77        ptr = &se_nacl->initiatorname[0];
  78        for (i = 0; i < 24; ) {
  79                if (!strncmp(&ptr[i], ":", 1)) {
  80                        i++;
  81                        continue;
  82                }
  83                ret = hex2bin(&buf[off++], &ptr[i], 1);
  84                if (ret < 0) {
  85                        pr_debug("%s: invalid hex string\n", __func__);
  86                        return ret;
  87                }
  88                i += 2;
  89        }
  90        /*
  91         * The FC Transport ID is a hardcoded 24-byte length
  92         */
  93        return 24;
  94}
  95
  96static int sbp_get_pr_transport_id(
  97        struct se_node_acl *nacl,
  98        int *format_code,
  99        unsigned char *buf)
 100{
 101        int ret;
 102
 103        ret = hex2bin(&buf[8], nacl->initiatorname, 8);
 104        if (ret) {
 105                pr_debug("%s: invalid hex string\n", __func__);
 106                return ret;
 107        }
 108
 109        return 24;
 110}
 111
 112static int srp_get_pr_transport_id(
 113        struct se_node_acl *nacl,
 114        int *format_code,
 115        unsigned char *buf)
 116{
 117        const char *p;
 118        unsigned len, count, leading_zero_bytes;
 119        int rc;
 120
 121        p = nacl->initiatorname;
 122        if (strncasecmp(p, "0x", 2) == 0)
 123                p += 2;
 124        len = strlen(p);
 125        if (len % 2)
 126                return -EINVAL;
 127
 128        count = min(len / 2, 16U);
 129        leading_zero_bytes = 16 - count;
 130        memset(buf + 8, 0, leading_zero_bytes);
 131        rc = hex2bin(buf + 8 + leading_zero_bytes, p, count);
 132        if (rc < 0) {
 133                pr_debug("hex2bin failed for %s: %d\n", __func__, rc);
 134                return rc;
 135        }
 136
 137        return 24;
 138}
 139
 140static int iscsi_get_pr_transport_id(
 141        struct se_node_acl *se_nacl,
 142        struct t10_pr_registration *pr_reg,
 143        int *format_code,
 144        unsigned char *buf)
 145{
 146        u32 off = 4, padding = 0;
 147        u16 len = 0;
 148
 149        spin_lock_irq(&se_nacl->nacl_sess_lock);
 150        /*
 151         * From spc4r17 Section 7.5.4.6: TransportID for initiator
 152         * ports using SCSI over iSCSI.
 153         *
 154         * The null-terminated, null-padded (see 4.4.2) ISCSI NAME field
 155         * shall contain the iSCSI name of an iSCSI initiator node (see
 156         * RFC 3720). The first ISCSI NAME field byte containing an ASCII
 157         * null character terminates the ISCSI NAME field without regard for
 158         * the specified length of the iSCSI TransportID or the contents of
 159         * the ADDITIONAL LENGTH field.
 160         */
 161        len = sprintf(&buf[off], "%s", se_nacl->initiatorname);
 162        /*
 163         * Add Extra byte for NULL terminator
 164         */
 165        len++;
 166        /*
 167         * If there is ISID present with the registration and *format code == 1
 168         * 1, use iSCSI Initiator port TransportID format.
 169         *
 170         * Otherwise use iSCSI Initiator device TransportID format that
 171         * does not contain the ASCII encoded iSCSI Initiator iSID value
 172         * provied by the iSCSi Initiator during the iSCSI login process.
 173         */
 174        if ((*format_code == 1) && (pr_reg->isid_present_at_reg)) {
 175                /*
 176                 * Set FORMAT CODE 01b for iSCSI Initiator port TransportID
 177                 * format.
 178                 */
 179                buf[0] |= 0x40;
 180                /*
 181                 * From spc4r17 Section 7.5.4.6: TransportID for initiator
 182                 * ports using SCSI over iSCSI.  Table 390
 183                 *
 184                 * The SEPARATOR field shall contain the five ASCII
 185                 * characters ",i,0x".
 186                 *
 187                 * The null-terminated, null-padded ISCSI INITIATOR SESSION ID
 188                 * field shall contain the iSCSI initiator session identifier
 189                 * (see RFC 3720) in the form of ASCII characters that are the
 190                 * hexadecimal digits converted from the binary iSCSI initiator
 191                 * session identifier value. The first ISCSI INITIATOR SESSION
 192                 * ID field byte containing an ASCII null character
 193                 */
 194                buf[off+len] = 0x2c; off++; /* ASCII Character: "," */
 195                buf[off+len] = 0x69; off++; /* ASCII Character: "i" */
 196                buf[off+len] = 0x2c; off++; /* ASCII Character: "," */
 197                buf[off+len] = 0x30; off++; /* ASCII Character: "0" */
 198                buf[off+len] = 0x78; off++; /* ASCII Character: "x" */
 199                len += 5;
 200                buf[off+len] = pr_reg->pr_reg_isid[0]; off++;
 201                buf[off+len] = pr_reg->pr_reg_isid[1]; off++;
 202                buf[off+len] = pr_reg->pr_reg_isid[2]; off++;
 203                buf[off+len] = pr_reg->pr_reg_isid[3]; off++;
 204                buf[off+len] = pr_reg->pr_reg_isid[4]; off++;
 205                buf[off+len] = pr_reg->pr_reg_isid[5]; off++;
 206                buf[off+len] = '\0'; off++;
 207                len += 7;
 208        }
 209        spin_unlock_irq(&se_nacl->nacl_sess_lock);
 210        /*
 211         * The ADDITIONAL LENGTH field specifies the number of bytes that follow
 212         * in the TransportID. The additional length shall be at least 20 and
 213         * shall be a multiple of four.
 214        */
 215        padding = ((-len) & 3);
 216        if (padding != 0)
 217                len += padding;
 218
 219        buf[2] = ((len >> 8) & 0xff);
 220        buf[3] = (len & 0xff);
 221        /*
 222         * Increment value for total payload + header length for
 223         * full status descriptor
 224         */
 225        len += 4;
 226
 227        return len;
 228}
 229
 230static int iscsi_get_pr_transport_id_len(
 231        struct se_node_acl *se_nacl,
 232        struct t10_pr_registration *pr_reg,
 233        int *format_code)
 234{
 235        u32 len = 0, padding = 0;
 236
 237        spin_lock_irq(&se_nacl->nacl_sess_lock);
 238        len = strlen(se_nacl->initiatorname);
 239        /*
 240         * Add extra byte for NULL terminator
 241         */
 242        len++;
 243        /*
 244         * If there is ISID present with the registration, use format code:
 245         * 01b: iSCSI Initiator port TransportID format
 246         *
 247         * If there is not an active iSCSI session, use format code:
 248         * 00b: iSCSI Initiator device TransportID format
 249         */
 250        if (pr_reg->isid_present_at_reg) {
 251                len += 5; /* For ",i,0x" ASCII separator */
 252                len += 7; /* For iSCSI Initiator Session ID + Null terminator */
 253                *format_code = 1;
 254        } else
 255                *format_code = 0;
 256        spin_unlock_irq(&se_nacl->nacl_sess_lock);
 257        /*
 258         * The ADDITIONAL LENGTH field specifies the number of bytes that follow
 259         * in the TransportID. The additional length shall be at least 20 and
 260         * shall be a multiple of four.
 261         */
 262        padding = ((-len) & 3);
 263        if (padding != 0)
 264                len += padding;
 265        /*
 266         * Increment value for total payload + header length for
 267         * full status descriptor
 268         */
 269        len += 4;
 270
 271        return len;
 272}
 273
 274static char *iscsi_parse_pr_out_transport_id(
 275        struct se_portal_group *se_tpg,
 276        const char *buf,
 277        u32 *out_tid_len,
 278        char **port_nexus_ptr)
 279{
 280        char *p;
 281        u32 tid_len, padding;
 282        int i;
 283        u16 add_len;
 284        u8 format_code = (buf[0] & 0xc0);
 285        /*
 286         * Check for FORMAT CODE 00b or 01b from spc4r17, section 7.5.4.6:
 287         *
 288         *       TransportID for initiator ports using SCSI over iSCSI,
 289         *       from Table 388 -- iSCSI TransportID formats.
 290         *
 291         *    00b     Initiator port is identified using the world wide unique
 292         *            SCSI device name of the iSCSI initiator
 293         *            device containing the initiator port (see table 389).
 294         *    01b     Initiator port is identified using the world wide unique
 295         *            initiator port identifier (see table 390).10b to 11b
 296         *            Reserved
 297         */
 298        if ((format_code != 0x00) && (format_code != 0x40)) {
 299                pr_err("Illegal format code: 0x%02x for iSCSI"
 300                        " Initiator Transport ID\n", format_code);
 301                return NULL;
 302        }
 303        /*
 304         * If the caller wants the TransportID Length, we set that value for the
 305         * entire iSCSI Tarnsport ID now.
 306         */
 307        if (out_tid_len) {
 308                /* The shift works thanks to integer promotion rules */
 309                add_len = (buf[2] << 8) | buf[3];
 310
 311                tid_len = strlen(&buf[4]);
 312                tid_len += 4; /* Add four bytes for iSCSI Transport ID header */
 313                tid_len += 1; /* Add one byte for NULL terminator */
 314                padding = ((-tid_len) & 3);
 315                if (padding != 0)
 316                        tid_len += padding;
 317
 318                if ((add_len + 4) != tid_len) {
 319                        pr_debug("LIO-Target Extracted add_len: %hu "
 320                                "does not match calculated tid_len: %u,"
 321                                " using tid_len instead\n", add_len+4, tid_len);
 322                        *out_tid_len = tid_len;
 323                } else
 324                        *out_tid_len = (add_len + 4);
 325        }
 326        /*
 327         * Check for ',i,0x' separator between iSCSI Name and iSCSI Initiator
 328         * Session ID as defined in Table 390 - iSCSI initiator port TransportID
 329         * format.
 330         */
 331        if (format_code == 0x40) {
 332                p = strstr(&buf[4], ",i,0x");
 333                if (!p) {
 334                        pr_err("Unable to locate \",i,0x\" separator"
 335                                " for Initiator port identifier: %s\n",
 336                                &buf[4]);
 337                        return NULL;
 338                }
 339                *p = '\0'; /* Terminate iSCSI Name */
 340                p += 5; /* Skip over ",i,0x" separator */
 341
 342                *port_nexus_ptr = p;
 343                /*
 344                 * Go ahead and do the lower case conversion of the received
 345                 * 12 ASCII characters representing the ISID in the TransportID
 346                 * for comparison against the running iSCSI session's ISID from
 347                 * iscsi_target.c:lio_sess_get_initiator_sid()
 348                 */
 349                for (i = 0; i < 12; i++) {
 350                        if (isdigit(*p)) {
 351                                p++;
 352                                continue;
 353                        }
 354                        *p = tolower(*p);
 355                        p++;
 356                }
 357        }
 358
 359        return (char *)&buf[4];
 360}
 361
 362int target_get_pr_transport_id_len(struct se_node_acl *nacl,
 363                struct t10_pr_registration *pr_reg, int *format_code)
 364{
 365        switch (nacl->se_tpg->proto_id) {
 366        case SCSI_PROTOCOL_FCP:
 367        case SCSI_PROTOCOL_SBP:
 368        case SCSI_PROTOCOL_SRP:
 369        case SCSI_PROTOCOL_SAS:
 370                break;
 371        case SCSI_PROTOCOL_ISCSI:
 372                return iscsi_get_pr_transport_id_len(nacl, pr_reg, format_code);
 373        default:
 374                pr_err("Unknown proto_id: 0x%02x\n", nacl->se_tpg->proto_id);
 375                return -EINVAL;
 376        }
 377
 378        /*
 379         * Most transports use a fixed length 24 byte identifier.
 380         */
 381        *format_code = 0;
 382        return 24;
 383}
 384
 385int target_get_pr_transport_id(struct se_node_acl *nacl,
 386                struct t10_pr_registration *pr_reg, int *format_code,
 387                unsigned char *buf)
 388{
 389        switch (nacl->se_tpg->proto_id) {
 390        case SCSI_PROTOCOL_SAS:
 391                return sas_get_pr_transport_id(nacl, format_code, buf);
 392        case SCSI_PROTOCOL_SBP:
 393                return sbp_get_pr_transport_id(nacl, format_code, buf);
 394        case SCSI_PROTOCOL_SRP:
 395                return srp_get_pr_transport_id(nacl, format_code, buf);
 396        case SCSI_PROTOCOL_FCP:
 397                return fc_get_pr_transport_id(nacl, format_code, buf);
 398        case SCSI_PROTOCOL_ISCSI:
 399                return iscsi_get_pr_transport_id(nacl, pr_reg, format_code,
 400                                buf);
 401        default:
 402                pr_err("Unknown proto_id: 0x%02x\n", nacl->se_tpg->proto_id);
 403                return -EINVAL;
 404        }
 405}
 406
 407const char *target_parse_pr_out_transport_id(struct se_portal_group *tpg,
 408                const char *buf, u32 *out_tid_len, char **port_nexus_ptr)
 409{
 410        u32 offset;
 411
 412        switch (tpg->proto_id) {
 413        case SCSI_PROTOCOL_SAS:
 414                /*
 415                 * Assume the FORMAT CODE 00b from spc4r17, 7.5.4.7 TransportID
 416                 * for initiator ports using SCSI over SAS Serial SCSI Protocol.
 417                 */
 418                offset = 4;
 419                break;
 420        case SCSI_PROTOCOL_SBP:
 421        case SCSI_PROTOCOL_SRP:
 422        case SCSI_PROTOCOL_FCP:
 423                offset = 8;
 424                break;
 425        case SCSI_PROTOCOL_ISCSI:
 426                return iscsi_parse_pr_out_transport_id(tpg, buf, out_tid_len,
 427                                        port_nexus_ptr);
 428        default:
 429                pr_err("Unknown proto_id: 0x%02x\n", tpg->proto_id);
 430                return NULL;
 431        }
 432
 433        *port_nexus_ptr = NULL;
 434        *out_tid_len = 24;
 435        return buf + offset;
 436}
 437