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 < 24; ) {
  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", __func__, 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        u16 len = 0;
 136
 137        spin_lock_irq(&se_nacl->nacl_sess_lock);
 138        /*
 139         * From spc4r17 Section 7.5.4.6: TransportID for initiator
 140         * ports using SCSI over iSCSI.
 141         *
 142         * The null-terminated, null-padded (see 4.4.2) ISCSI NAME field
 143         * shall contain the iSCSI name of an iSCSI initiator node (see
 144         * RFC 3720). The first ISCSI NAME field byte containing an ASCII
 145         * null character terminates the ISCSI NAME field without regard for
 146         * the specified length of the iSCSI TransportID or the contents of
 147         * the ADDITIONAL LENGTH field.
 148         */
 149        len = sprintf(&buf[off], "%s", se_nacl->initiatorname);
 150        /*
 151         * Add Extra byte for NULL terminator
 152         */
 153        len++;
 154        /*
 155         * If there is ISID present with the registration and *format code == 1
 156         * 1, use iSCSI Initiator port TransportID format.
 157         *
 158         * Otherwise use iSCSI Initiator device TransportID format that
 159         * does not contain the ASCII encoded iSCSI Initiator iSID value
 160         * provied by the iSCSi Initiator during the iSCSI login process.
 161         */
 162        if ((*format_code == 1) && (pr_reg->isid_present_at_reg)) {
 163                /*
 164                 * Set FORMAT CODE 01b for iSCSI Initiator port TransportID
 165                 * format.
 166                 */
 167                buf[0] |= 0x40;
 168                /*
 169                 * From spc4r17 Section 7.5.4.6: TransportID for initiator
 170                 * ports using SCSI over iSCSI.  Table 390
 171                 *
 172                 * The SEPARATOR field shall contain the five ASCII
 173                 * characters ",i,0x".
 174                 *
 175                 * The null-terminated, null-padded ISCSI INITIATOR SESSION ID
 176                 * field shall contain the iSCSI initiator session identifier
 177                 * (see RFC 3720) in the form of ASCII characters that are the
 178                 * hexadecimal digits converted from the binary iSCSI initiator
 179                 * session identifier value. The first ISCSI INITIATOR SESSION
 180                 * ID field byte containing an ASCII null character
 181                 */
 182                buf[off+len] = 0x2c; off++; /* ASCII Character: "," */
 183                buf[off+len] = 0x69; off++; /* ASCII Character: "i" */
 184                buf[off+len] = 0x2c; off++; /* ASCII Character: "," */
 185                buf[off+len] = 0x30; off++; /* ASCII Character: "0" */
 186                buf[off+len] = 0x78; off++; /* ASCII Character: "x" */
 187                len += 5;
 188                buf[off+len] = pr_reg->pr_reg_isid[0]; off++;
 189                buf[off+len] = pr_reg->pr_reg_isid[1]; off++;
 190                buf[off+len] = pr_reg->pr_reg_isid[2]; off++;
 191                buf[off+len] = pr_reg->pr_reg_isid[3]; off++;
 192                buf[off+len] = pr_reg->pr_reg_isid[4]; off++;
 193                buf[off+len] = pr_reg->pr_reg_isid[5]; off++;
 194                buf[off+len] = '\0'; off++;
 195                len += 7;
 196        }
 197        spin_unlock_irq(&se_nacl->nacl_sess_lock);
 198        /*
 199         * The ADDITIONAL LENGTH field specifies the number of bytes that follow
 200         * in the TransportID. The additional length shall be at least 20 and
 201         * shall be a multiple of four.
 202        */
 203        padding = ((-len) & 3);
 204        if (padding != 0)
 205                len += padding;
 206
 207        put_unaligned_be16(len, &buf[2]);
 208        /*
 209         * Increment value for total payload + header length for
 210         * full status descriptor
 211         */
 212        len += 4;
 213
 214        return len;
 215}
 216
 217static int iscsi_get_pr_transport_id_len(
 218        struct se_node_acl *se_nacl,
 219        struct t10_pr_registration *pr_reg,
 220        int *format_code)
 221{
 222        u32 len = 0, padding = 0;
 223
 224        spin_lock_irq(&se_nacl->nacl_sess_lock);
 225        len = strlen(se_nacl->initiatorname);
 226        /*
 227         * Add extra byte for NULL terminator
 228         */
 229        len++;
 230        /*
 231         * If there is ISID present with the registration, use format code:
 232         * 01b: iSCSI Initiator port TransportID format
 233         *
 234         * If there is not an active iSCSI session, use format code:
 235         * 00b: iSCSI Initiator device TransportID format
 236         */
 237        if (pr_reg->isid_present_at_reg) {
 238                len += 5; /* For ",i,0x" ASCII separator */
 239                len += 7; /* For iSCSI Initiator Session ID + Null terminator */
 240                *format_code = 1;
 241        } else
 242                *format_code = 0;
 243        spin_unlock_irq(&se_nacl->nacl_sess_lock);
 244        /*
 245         * The ADDITIONAL LENGTH field specifies the number of bytes that follow
 246         * in the TransportID. The additional length shall be at least 20 and
 247         * shall be a multiple of four.
 248         */
 249        padding = ((-len) & 3);
 250        if (padding != 0)
 251                len += padding;
 252        /*
 253         * Increment value for total payload + header length for
 254         * full status descriptor
 255         */
 256        len += 4;
 257
 258        return len;
 259}
 260
 261static char *iscsi_parse_pr_out_transport_id(
 262        struct se_portal_group *se_tpg,
 263        char *buf,
 264        u32 *out_tid_len,
 265        char **port_nexus_ptr)
 266{
 267        char *p;
 268        u32 tid_len, padding;
 269        int i;
 270        u16 add_len;
 271        u8 format_code = (buf[0] & 0xc0);
 272        /*
 273         * Check for FORMAT CODE 00b or 01b from spc4r17, section 7.5.4.6:
 274         *
 275         *       TransportID for initiator ports using SCSI over iSCSI,
 276         *       from Table 388 -- iSCSI TransportID formats.
 277         *
 278         *    00b     Initiator port is identified using the world wide unique
 279         *            SCSI device name of the iSCSI initiator
 280         *            device containing the initiator port (see table 389).
 281         *    01b     Initiator port is identified using the world wide unique
 282         *            initiator port identifier (see table 390).10b to 11b
 283         *            Reserved
 284         */
 285        if ((format_code != 0x00) && (format_code != 0x40)) {
 286                pr_err("Illegal format code: 0x%02x for iSCSI"
 287                        " Initiator Transport ID\n", format_code);
 288                return NULL;
 289        }
 290        /*
 291         * If the caller wants the TransportID Length, we set that value for the
 292         * entire iSCSI Tarnsport ID now.
 293         */
 294        if (out_tid_len) {
 295                /* The shift works thanks to integer promotion rules */
 296                add_len = get_unaligned_be16(&buf[2]);
 297
 298                tid_len = strlen(&buf[4]);
 299                tid_len += 4; /* Add four bytes for iSCSI Transport ID header */
 300                tid_len += 1; /* Add one byte for NULL terminator */
 301                padding = ((-tid_len) & 3);
 302                if (padding != 0)
 303                        tid_len += padding;
 304
 305                if ((add_len + 4) != tid_len) {
 306                        pr_debug("LIO-Target Extracted add_len: %hu "
 307                                "does not match calculated tid_len: %u,"
 308                                " using tid_len instead\n", add_len+4, tid_len);
 309                        *out_tid_len = tid_len;
 310                } else
 311                        *out_tid_len = (add_len + 4);
 312        }
 313        /*
 314         * Check for ',i,0x' separator between iSCSI Name and iSCSI Initiator
 315         * Session ID as defined in Table 390 - iSCSI initiator port TransportID
 316         * format.
 317         */
 318        if (format_code == 0x40) {
 319                p = strstr(&buf[4], ",i,0x");
 320                if (!p) {
 321                        pr_err("Unable to locate \",i,0x\" separator"
 322                                " for Initiator port identifier: %s\n",
 323                                &buf[4]);
 324                        return NULL;
 325                }
 326                *p = '\0'; /* Terminate iSCSI Name */
 327                p += 5; /* Skip over ",i,0x" separator */
 328
 329                *port_nexus_ptr = p;
 330                /*
 331                 * Go ahead and do the lower case conversion of the received
 332                 * 12 ASCII characters representing the ISID in the TransportID
 333                 * for comparison against the running iSCSI session's ISID from
 334                 * iscsi_target.c:lio_sess_get_initiator_sid()
 335                 */
 336                for (i = 0; i < 12; i++) {
 337                        if (isdigit(*p)) {
 338                                p++;
 339                                continue;
 340                        }
 341                        *p = tolower(*p);
 342                        p++;
 343                }
 344        }
 345
 346        return &buf[4];
 347}
 348
 349int target_get_pr_transport_id_len(struct se_node_acl *nacl,
 350                struct t10_pr_registration *pr_reg, int *format_code)
 351{
 352        switch (nacl->se_tpg->proto_id) {
 353        case SCSI_PROTOCOL_FCP:
 354        case SCSI_PROTOCOL_SBP:
 355        case SCSI_PROTOCOL_SRP:
 356        case SCSI_PROTOCOL_SAS:
 357                break;
 358        case SCSI_PROTOCOL_ISCSI:
 359                return iscsi_get_pr_transport_id_len(nacl, pr_reg, format_code);
 360        default:
 361                pr_err("Unknown proto_id: 0x%02x\n", nacl->se_tpg->proto_id);
 362                return -EINVAL;
 363        }
 364
 365        /*
 366         * Most transports use a fixed length 24 byte identifier.
 367         */
 368        *format_code = 0;
 369        return 24;
 370}
 371
 372int target_get_pr_transport_id(struct se_node_acl *nacl,
 373                struct t10_pr_registration *pr_reg, int *format_code,
 374                unsigned char *buf)
 375{
 376        switch (nacl->se_tpg->proto_id) {
 377        case SCSI_PROTOCOL_SAS:
 378                return sas_get_pr_transport_id(nacl, format_code, buf);
 379        case SCSI_PROTOCOL_SBP:
 380                return sbp_get_pr_transport_id(nacl, format_code, buf);
 381        case SCSI_PROTOCOL_SRP:
 382                return srp_get_pr_transport_id(nacl, format_code, buf);
 383        case SCSI_PROTOCOL_FCP:
 384                return fc_get_pr_transport_id(nacl, format_code, buf);
 385        case SCSI_PROTOCOL_ISCSI:
 386                return iscsi_get_pr_transport_id(nacl, pr_reg, format_code,
 387                                buf);
 388        default:
 389                pr_err("Unknown proto_id: 0x%02x\n", nacl->se_tpg->proto_id);
 390                return -EINVAL;
 391        }
 392}
 393
 394const char *target_parse_pr_out_transport_id(struct se_portal_group *tpg,
 395                char *buf, u32 *out_tid_len, char **port_nexus_ptr)
 396{
 397        u32 offset;
 398
 399        switch (tpg->proto_id) {
 400        case SCSI_PROTOCOL_SAS:
 401                /*
 402                 * Assume the FORMAT CODE 00b from spc4r17, 7.5.4.7 TransportID
 403                 * for initiator ports using SCSI over SAS Serial SCSI Protocol.
 404                 */
 405                offset = 4;
 406                break;
 407        case SCSI_PROTOCOL_SBP:
 408        case SCSI_PROTOCOL_SRP:
 409        case SCSI_PROTOCOL_FCP:
 410                offset = 8;
 411                break;
 412        case SCSI_PROTOCOL_ISCSI:
 413                return iscsi_parse_pr_out_transport_id(tpg, buf, out_tid_len,
 414                                        port_nexus_ptr);
 415        default:
 416                pr_err("Unknown proto_id: 0x%02x\n", tpg->proto_id);
 417                return NULL;
 418        }
 419
 420        *port_nexus_ptr = NULL;
 421        *out_tid_len = 24;
 422        return buf + offset;
 423}
 424