LXR linux/drivers/target/target_core_fabric

   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*******************************************************************************
   3 * Filename:  target_core_fabric_lib.c
   4 *
   5 * This file contains generic high level protocol identifier and PR
   6 * handlers for TCM fabric modules
   7 *
   8 * (c) Copyright 2010-2013 Datera, Inc.
   9 *
  10 * Nicholas A. Bellinger <nab@linux-iscsi.org>
  11 *
  12 ******************************************************************************/
  13
  14/*
  15 * See SPC4, section 7.5 "Protocol specific parameters" for details
  16 * on the formats implemented in this file.
  17 */
  18
  19#include <linux/kernel.h>
  20#include <linux/string.h>
  21#include <linux/ctype.h>
  22#include <linux/spinlock.h>
  23#include <linux/export.h>
  24#include <asm/unaligned.h>
  25
  26#include <scsi/scsi_proto.h>
  27
  28#include <target/target_core_base.h>
  29#include <target/target_core_fabric.h>
  30
  31#include "target_core_internal.h"
  32#include "target_core_pr.h"
  33
  34
  35static int sas_get_pr_transport_id(
  36        struct se_node_acl *nacl,
  37        int *format_code,
  38        unsigned char *buf)
  39{
  40        int ret;
  41
  42        /* Skip over 'naa. prefix */
  43        ret = hex2bin(&buf[4], &nacl->initiatorname[4], 8);
  44        if (ret) {
  45                pr_debug("%s: invalid hex string\n", __func__);
  46                return ret;
  47        }
  48
  49        return 24;
  50}
  51
  52static int fc_get_pr_transport_id(
  53        struct se_node_acl *se_nacl,
  54        int *format_code,
  55        unsigned char *buf)
  56{
  57        unsigned char *ptr;
  58        int i, ret;
  59        u32 off = 8;
  60
  61        /*
  62         * We convert the ASCII formatted N Port name into a binary
  63         * encoded TransportID.
  64         */
  65        ptr = &se_nacl->initiatorname[0];
  66        for (i = 0; i < 23; ) {
  67                if (!strncmp(&ptr[i], ":", 1)) {
  68                        i++;
  69                        continue;
  70                }
  71                ret = hex2bin(&buf[off++], &ptr[i], 1);
  72                if (ret < 0) {
  73                        pr_debug("%s: invalid hex string\n", __func__);
  74                        return ret;
  75                }
  76                i += 2;
  77        }
  78        /*
  79         * The FC Transport ID is a hardcoded 24-byte length
  80         */
  81        return 24;
  82}
  83
  84static int sbp_get_pr_transport_id(
  85        struct se_node_acl *nacl,
  86        int *format_code,
  87        unsigned char *buf)
  88{
  89        int ret;
  90
  91        ret = hex2bin(&buf[8], nacl->initiatorname, 8);
  92        if (ret) {
  93                pr_debug("%s: invalid hex string\n", __func__);
  94                return ret;
  95        }
  96
  97        return 24;
  98}
  99
 100static int srp_get_pr_transport_id(
 101        struct se_node_acl *nacl,
 102        int *format_code,
 103        unsigned char *buf)
 104{
 105        const char *p;
 106        unsigned len, count, leading_zero_bytes;
 107        int rc;
 108
 109        p = nacl->initiatorname;
 110        if (strncasecmp(p, "0x", 2) == 0)
 111                p += 2;
 112        len = strlen(p);
 113        if (len % 2)
 114                return -EINVAL;
 115
 116        count = min(len / 2, 16U);
 117        leading_zero_bytes = 16 - count;
 118        memset(buf + 8, 0, leading_zero_bytes);
 119        rc = hex2bin(buf + 8 + leading_zero_bytes, p, count);
 120        if (rc < 0) {
 121                pr_debug("hex2bin failed for %s: %d\n", p, rc);
 122                return rc;
 123        }
 124
 125        return 24;
 126}
 127
 128static int iscsi_get_pr_transport_id(
 129        struct se_node_acl *se_nacl,
 130        struct t10_pr_registration *pr_reg,
 131        int *format_code,
 132        unsigned char *buf)
 133{
 134        u32 off = 4, padding = 0;
 135        int isid_len;
 136        u16 len = 0;
 137
 138        spin_lock_irq(&se_nacl->nacl_sess_lock);
 139        /*
 140         * Only null terminate the last field.
 141         *
 142         * From spc4r37 section 7.6.4.6: TransportID for initiator ports using
 143         * SCSI over iSCSI.
 144         *
 145         * Table 507 TPID=0 Initiator device TransportID
 146         *
 147         * The null-terminated, null-padded (see 4.3.2) ISCSI NAME field shall
 148         * contain the iSCSI name of an iSCSI initiator node (see RFC 7143).
 149         * The first ISCSI NAME field byte containing an ASCII null character
 150         * terminates the ISCSI NAME field without regard for the specified
 151         * length of the iSCSI TransportID or the contents of the ADDITIONAL
 152         * LENGTH field.
 153         */
 154        len = sprintf(&buf[off], "%s", se_nacl->initiatorname);
 155        off += len;
 156        if ((*format_code == 1) && (pr_reg->isid_present_at_reg)) {
 157                /*
 158                 * Set FORMAT CODE 01b for iSCSI Initiator port TransportID
 159                 * format.
 160                 */
 161                buf[0] |= 0x40;
 162                /*
 163                 * From spc4r37 Section 7.6.4.6
 164                 *
 165                 * Table 508 TPID=1 Initiator port TransportID.
 166                 *
 167                 * The ISCSI NAME field shall not be null-terminated
 168                 * (see 4.3.2) and shall not be padded.
 169                 *
 170                 * The SEPARATOR field shall contain the five ASCII
 171                 * characters ",i,0x".
 172                 *
 173                 * The null-terminated, null-padded ISCSI INITIATOR SESSION ID
 174                 * field shall contain the iSCSI initiator session identifier
 175                 * (see RFC 3720) in the form of ASCII characters that are the
 176                 * hexadecimal digits converted from the binary iSCSI initiator
 177                 * session identifier value. The first ISCSI INITIATOR SESSION
 178                 * ID field byte containing an ASCII null character terminates
 179                 * the ISCSI INITIATOR SESSION ID field without regard for the
 180                 * specified length of the iSCSI TransportID or the contents
 181                 * of the ADDITIONAL LENGTH field.
 182                 */
 183                buf[off++] = 0x2c; /* ASCII Character: "," */
 184                buf[off++] = 0x69; /* ASCII Character: "i" */
 185                buf[off++] = 0x2c; /* ASCII Character: "," */
 186                buf[off++] = 0x30; /* ASCII Character: "0" */
 187                buf[off++] = 0x78; /* ASCII Character: "x" */
 188                len += 5;
 189
 190                isid_len = sprintf(buf + off, "%s", pr_reg->pr_reg_isid);
 191                off += isid_len;
 192                len += isid_len;
 193        }
 194        buf[off] = '\0';
 195        len += 1;
 196        spin_unlock_irq(&se_nacl->nacl_sess_lock);
 197        /*
 198         * The ADDITIONAL LENGTH field specifies the number of bytes that follow
 199         * in the TransportID. The additional length shall be at least 20 and
 200         * shall be a multiple of four.
 201        */
 202        padding = ((-len) & 3);
 203        if (padding != 0)
 204                len += padding;
 205
 206        put_unaligned_be16(len, &buf[2]);
 207        /*
 208         * Increment value for total payload + header length for
 209         * full status descriptor
 210         */
 211        len += 4;
 212
 213        return len;
 214}
 215
 216static int iscsi_get_pr_transport_id_len(
 217        struct se_node_acl *se_nacl,
 218        struct t10_pr_registration *pr_reg,
 219        int *format_code)
 220{
 221        u32 len = 0, padding = 0;
 222
 223        spin_lock_irq(&se_nacl->nacl_sess_lock);
 224        len = strlen(se_nacl->initiatorname);
 225        /*
 226         * Add extra byte for NULL terminator
 227         */
 228        len++;
 229        /*
 230         * If there is ISID present with the registration, use format code:
 231         * 01b: iSCSI Initiator port TransportID format
 232         *
 233         * If there is not an active iSCSI session, use format code:
 234         * 00b: iSCSI Initiator device TransportID format
 235         */
 236        if (pr_reg->isid_present_at_reg) {
 237                len += 5; /* For ",i,0x" ASCII separator */
 238                len += strlen(pr_reg->pr_reg_isid);
 239                *format_code = 1;
 240        } else
 241                *format_code = 0;
 242        spin_unlock_irq(&se_nacl->nacl_sess_lock);
 243        /*
 244         * The ADDITIONAL LENGTH field specifies the number of bytes that follow
 245         * in the TransportID. The additional length shall be at least 20 and
 246         * shall be a multiple of four.
 247         */
 248        padding = ((-len) & 3);
 249        if (padding != 0)
 250                len += padding;
 251        /*
 252         * Increment value for total payload + header length for
 253         * full status descriptor
 254         */
 255        len += 4;
 256
 257        return len;
 258}
 259
 260static char *iscsi_parse_pr_out_transport_id(
 261        struct se_portal_group *se_tpg,
 262        char *buf,
 263        u32 *out_tid_len,
 264        char **port_nexus_ptr)
 265{
 266        char *p;
 267        int i;
 268        u8 format_code = (buf[0] & 0xc0);
 269        /*
 270         * Check for FORMAT CODE 00b or 01b from spc4r17, section 7.5.4.6:
 271         *
 272         *       TransportID for initiator ports using SCSI over iSCSI,
 273         *       from Table 388 -- iSCSI TransportID formats.
 274         *
 275         *    00b     Initiator port is identified using the world wide unique
 276         *            SCSI device name of the iSCSI initiator
 277         *            device containing the initiator port (see table 389).
 278         *    01b     Initiator port is identified using the world wide unique
 279         *            initiator port identifier (see table 390).10b to 11b
 280         *            Reserved
 281         */
 282        if ((format_code != 0x00) && (format_code != 0x40)) {
 283                pr_err("Illegal format code: 0x%02x for iSCSI"
 284                        " Initiator Transport ID\n", format_code);
 285                return NULL;
 286        }
 287        /*
 288         * If the caller wants the TransportID Length, we set that value for the
 289         * entire iSCSI Tarnsport ID now.
 290         */
 291        if (out_tid_len) {
 292                /* The shift works thanks to integer promotion rules */
 293                *out_tid_len = get_unaligned_be16(&buf[2]);
 294                /* Add four bytes for iSCSI Transport ID header */
 295                *out_tid_len += 4;
 296        }
 297
 298        /*
 299         * Check for ',i,0x' separator between iSCSI Name and iSCSI Initiator
 300         * Session ID as defined in Table 390 - iSCSI initiator port TransportID
 301         * format.
 302         */
 303        if (format_code == 0x40) {
 304                p = strstr(&buf[4], ",i,0x");
 305                if (!p) {
 306                        pr_err("Unable to locate \",i,0x\" separator"
 307                                " for Initiator port identifier: %s\n",
 308                                &buf[4]);
 309                        return NULL;
 310                }
 311                *p = '\0'; /* Terminate iSCSI Name */
 312                p += 5; /* Skip over ",i,0x" separator */
 313
 314                *port_nexus_ptr = p;
 315                /*
 316                 * Go ahead and do the lower case conversion of the received
 317                 * 12 ASCII characters representing the ISID in the TransportID
 318                 * for comparison against the running iSCSI session's ISID from
 319                 * iscsi_target.c:lio_sess_get_initiator_sid()
 320                 */
 321                for (i = 0; i < 12; i++) {
 322                        /*
 323                         * The first ISCSI INITIATOR SESSION ID field byte
 324                         * containing an ASCII null character terminates the
 325                         * ISCSI INITIATOR SESSION ID field without regard for
 326                         * the specified length of the iSCSI TransportID or the
 327                         * contents of the ADDITIONAL LENGTH field.
 328                         */
 329                        if (*p == '\0')
 330                                break;
 331
 332                        if (isdigit(*p)) {
 333                                p++;
 334                                continue;
 335                        }
 336                        *p = tolower(*p);
 337                        p++;
 338                }
 339        } else
 340                *port_nexus_ptr = NULL;
 341
 342        return &buf[4];
 343}
 344
 345int target_get_pr_transport_id_len(struct se_node_acl *nacl,
 346                struct t10_pr_registration *pr_reg, int *format_code)
 347{
 348        switch (nacl->se_tpg->proto_id) {
 349        case SCSI_PROTOCOL_FCP:
 350        case SCSI_PROTOCOL_SBP:
 351        case SCSI_PROTOCOL_SRP:
 352        case SCSI_PROTOCOL_SAS:
 353                break;
 354        case SCSI_PROTOCOL_ISCSI:
 355                return iscsi_get_pr_transport_id_len(nacl, pr_reg, format_code);
 356        default:
 357                pr_err("Unknown proto_id: 0x%02x\n", nacl->se_tpg->proto_id);
 358                return -EINVAL;
 359        }
 360
 361        /*
 362         * Most transports use a fixed length 24 byte identifier.
 363         */
 364        *format_code = 0;
 365        return 24;
 366}
 367
 368int target_get_pr_transport_id(struct se_node_acl *nacl,
 369                struct t10_pr_registration *pr_reg, int *format_code,
 370                unsigned char *buf)
 371{
 372        switch (nacl->se_tpg->proto_id) {
 373        case SCSI_PROTOCOL_SAS:
 374                return sas_get_pr_transport_id(nacl, format_code, buf);
 375        case SCSI_PROTOCOL_SBP:
 376                return sbp_get_pr_transport_id(nacl, format_code, buf);
 377        case SCSI_PROTOCOL_SRP:
 378                return srp_get_pr_transport_id(nacl, format_code, buf);
 379        case SCSI_PROTOCOL_FCP:
 380                return fc_get_pr_transport_id(nacl, format_code, buf);
 381        case SCSI_PROTOCOL_ISCSI:
 382                return iscsi_get_pr_transport_id(nacl, pr_reg, format_code,
 383                                buf);
 384        default:
 385                pr_err("Unknown proto_id: 0x%02x\n", nacl->se_tpg->proto_id);
 386                return -EINVAL;
 387        }
 388}
 389
 390const char *target_parse_pr_out_transport_id(struct se_portal_group *tpg,
 391                char *buf, u32 *out_tid_len, char **port_nexus_ptr)
 392{
 393        u32 offset;
 394
 395        switch (tpg->proto_id) {
 396        case SCSI_PROTOCOL_SAS:
 397                /*
 398                 * Assume the FORMAT CODE 00b from spc4r17, 7.5.4.7 TransportID
 399                 * for initiator ports using SCSI over SAS Serial SCSI Protocol.
 400                 */
 401                offset = 4;
 402                break;
 403        case SCSI_PROTOCOL_SBP:
 404        case SCSI_PROTOCOL_SRP:
 405        case SCSI_PROTOCOL_FCP:
 406                offset = 8;
 407                break;
 408        case SCSI_PROTOCOL_ISCSI:
 409                return iscsi_parse_pr_out_transport_id(tpg, buf, out_tid_len,
 410                                        port_nexus_ptr);
 411        default:
 412                pr_err("Unknown proto_id: 0x%02x\n", tpg->proto_id);
 413                return NULL;
 414        }
 415
 416        *port_nexus_ptr = NULL;
 417        *out_tid_len = 24;
 418        return buf + offset;
 419}
 420