drivers/target/target_core_fabric_lib.c

   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
  35 static 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
  52 static 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
  84 static 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
 100 static 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
 128 static 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
 217 static 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
 261 static 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
 349 int 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
 372 int 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
 394 const 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 }