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(dst: &buf[4], src: &nacl->initiatorname[4], count: 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(dst: &buf[off++], src: &ptr[i], count: 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(dst: &buf[8], src: nacl->initiatorname, count: 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(s1: p, s2: "0x", n: 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(dst: buf + 8 + leading_zero_bytes, src: 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(lock: &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: &buf[off], fmt: "%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: buf + off, fmt: "%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(lock: &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(val: len, p: &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(lock: &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(lock: &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(p: &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(c: *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(se_nacl: 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(se_nacl: nacl, format_code, buf);
381 case SCSI_PROTOCOL_ISCSI:
382 return iscsi_get_pr_transport_id(se_nacl: 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(se_tpg: 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

source code of linux/drivers/target/target_core_fabric_lib.c