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
48static 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
65static 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
97static 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
113static 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", __func__, rc);
135 return rc;
136 }
137
138 return 24;
139}
140
141static 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
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 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
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 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