drivers/target/target_core_fabric_lib.c

   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 #include <asm/unaligned.h>
  38
  39 #include <scsi/scsi_proto.h>
  40
  41 #include <target/target_core_base.h>
  42 #include <target/target_core_fabric.h>
  43
  44 #include "target_core_internal.h"
  45 #include "target_core_pr.h"
  46
  47
  48 static int sas_get_pr_transport_id(
  49         struct se_node_acl *nacl,
  50         int *format_code,
  51         unsigned char *buf)
  52 {
  53         int ret;
  54
  55         /* Skip over 'naa. prefix */
  56         ret = hex2bin(&buf[4], &nacl->initiatorname[4], 8);
  57         if (ret) {
  58                 pr_debug("%s: invalid hex string\n", __func__);
  59                 return ret;
  60         }
  61
  62         return 24;
  63 }
  64
  65 static int fc_get_pr_transport_id(
  66         struct se_node_acl *se_nacl,
  67         int *format_code,
  68         unsigned char *buf)
  69 {
  70         unsigned char *ptr;
  71         int i, ret;
  72         u32 off = 8;
  73
  74         /*
  75          * We convert the ASCII formatted N Port name into a binary
  76          * encoded TransportID.
  77          */
  78         ptr = &se_nacl->initiatorname[0];
  79         for (i = 0; i < 24; ) {
  80                 if (!strncmp(&ptr[i], ":", 1)) {
  81                         i++;
  82                         continue;
  83                 }
  84                 ret = hex2bin(&buf[off++], &ptr[i], 1);
  85                 if (ret < 0) {
  86                         pr_debug("%s: invalid hex string\n", __func__);
  87                         return ret;
  88                 }
  89                 i += 2;
  90         }
  91         /*
  92          * The FC Transport ID is a hardcoded 24-byte length
  93          */
  94         return 24;
  95 }
  96
  97 static int sbp_get_pr_transport_id(
  98         struct se_node_acl *nacl,
  99         int *format_code,
 100         unsigned char *buf)
 101 {
 102         int ret;
 103
 104         ret = hex2bin(&buf[8], nacl->initiatorname, 8);
 105         if (ret) {
 106                 pr_debug("%s: invalid hex string\n", __func__);
 107                 return ret;
 108         }
 109
 110         return 24;
 111 }
 112
 113 static int srp_get_pr_transport_id(
 114         struct se_node_acl *nacl,
 115         int *format_code,
 116         unsigned char *buf)
 117 {
 118         const char *p;
 119         unsigned len, count, leading_zero_bytes;
 120         int rc;
 121
 122         p = nacl->initiatorname;
 123         if (strncasecmp(p, "0x", 2) == 0)
 124                 p += 2;
 125         len = strlen(p);
 126         if (len % 2)
 127                 return -EINVAL;
 128
 129         count = min(len / 2, 16U);
 130         leading_zero_bytes = 16 - count;
 131         memset(buf + 8, 0, leading_zero_bytes);
 132         rc = hex2bin(buf + 8 + leading_zero_bytes, p, count);
 133         if (rc < 0) {
 134                 pr_debug("hex2bin failed for %s: %d\n", p, rc);
 135                 return rc;
 136         }
 137
 138         return 24;
 139 }
 140
 141 static int iscsi_get_pr_transport_id(
 142         struct se_node_acl *se_nacl,
 143         struct t10_pr_registration *pr_reg,
 144         int *format_code,
 145         unsigned char *buf)
 146 {
 147         u32 off = 4, padding = 0;
 148         u16 len = 0;
 149
 150         spin_lock_irq(&se_nacl->nacl_sess_lock);
 151         /*
 152          * From spc4r17 Section 7.5.4.6: TransportID for initiator
 153          * ports using SCSI over iSCSI.
 154          *
 155          * The null-terminated, null-padded (see 4.4.2) ISCSI NAME field
 156          * shall contain the iSCSI name of an iSCSI initiator node (see
 157          * RFC 3720). The first ISCSI NAME field byte containing an ASCII
 158          * null character terminates the ISCSI NAME field without regard for
 159          * the specified length of the iSCSI TransportID or the contents of
 160          * the ADDITIONAL LENGTH field.
 161          */
 162         len = sprintf(&buf[off], "%s", se_nacl->initiatorname);
 163         /*
 164          * Add Extra byte for NULL terminator
 165          */
 166         len++;
 167         /*
 168          * If there is ISID present with the registration and *format code == 1
 169          * 1, use iSCSI Initiator port TransportID format.
 170          *
 171          * Otherwise use iSCSI Initiator device TransportID format that
 172          * does not contain the ASCII encoded iSCSI Initiator iSID value
 173          * provied by the iSCSi Initiator during the iSCSI login process.
 174          */
 175         if ((*format_code == 1) && (pr_reg->isid_present_at_reg)) {
 176                 /*
 177                  * Set FORMAT CODE 01b for iSCSI Initiator port TransportID
 178                  * format.
 179                  */
 180                 buf[0] |= 0x40;
 181                 /*
 182                  * From spc4r17 Section 7.5.4.6: TransportID for initiator
 183                  * ports using SCSI over iSCSI.  Table 390
 184                  *
 185                  * The SEPARATOR field shall contain the five ASCII
 186                  * characters ",i,0x".
 187                  *
 188                  * The null-terminated, null-padded ISCSI INITIATOR SESSION ID
 189                  * field shall contain the iSCSI initiator session identifier
 190                  * (see RFC 3720) in the form of ASCII characters that are the
 191                  * hexadecimal digits converted from the binary iSCSI initiator
 192                  * session identifier value. The first ISCSI INITIATOR SESSION
 193                  * ID field byte containing an ASCII null character
 194                  */
 195                 buf[off+len] = 0x2c; off++; /* ASCII Character: "," */
 196                 buf[off+len] = 0x69; off++; /* ASCII Character: "i" */
 197                 buf[off+len] = 0x2c; off++; /* ASCII Character: "," */
 198                 buf[off+len] = 0x30; off++; /* ASCII Character: "0" */
 199                 buf[off+len] = 0x78; off++; /* ASCII Character: "x" */
 200                 len += 5;
 201                 buf[off+len] = pr_reg->pr_reg_isid[0]; off++;
 202                 buf[off+len] = pr_reg->pr_reg_isid[1]; off++;
 203                 buf[off+len] = pr_reg->pr_reg_isid[2]; off++;
 204                 buf[off+len] = pr_reg->pr_reg_isid[3]; off++;
 205                 buf[off+len] = pr_reg->pr_reg_isid[4]; off++;
 206                 buf[off+len] = pr_reg->pr_reg_isid[5]; off++;
 207                 buf[off+len] = '\0'; off++;
 208                 len += 7;
 209         }
 210         spin_unlock_irq(&se_nacl->nacl_sess_lock);
 211         /*
 212          * The ADDITIONAL LENGTH field specifies the number of bytes that follow
 213          * in the TransportID. The additional length shall be at least 20 and
 214          * shall be a multiple of four.
 215         */
 216         padding = ((-len) & 3);
 217         if (padding != 0)
 218                 len += padding;
 219
 220         put_unaligned_be16(len, &buf[2]);
 221         /*
 222          * Increment value for total payload + header length for
 223          * full status descriptor
 224          */
 225         len += 4;
 226
 227         return len;
 228 }
 229
 230 static 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
 274 static char *iscsi_parse_pr_out_transport_id(
 275         struct se_portal_group *se_tpg,
 276         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 = get_unaligned_be16(&buf[2]);
 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 &buf[4];
 360 }
 361
 362 int 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
 385 int 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
 407 const char *target_parse_pr_out_transport_id(struct se_portal_group *tpg,
 408                 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 }