xref: /linux/drivers/target/target_core_fabric_lib.c (revision 69050f8d6d075dc01af7a5f2f550a8067510366f)
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/hex.h>
20 #include <linux/kernel.h>
21 #include <linux/string.h>
22 #include <linux/ctype.h>
23 #include <linux/spinlock.h>
24 #include <linux/export.h>
25 #include <linux/unaligned.h>
26 
27 #include <scsi/scsi_proto.h>
28 
29 #include <target/target_core_base.h>
30 #include <target/target_core_fabric.h>
31 
32 #include "target_core_internal.h"
33 #include "target_core_pr.h"
34 
35 
36 static int sas_get_pr_transport_id(
37 	struct se_node_acl *nacl,
38 	int *format_code,
39 	unsigned char *buf)
40 {
41 	int ret;
42 
43 	/* Skip over 'naa. prefix */
44 	ret = hex2bin(&buf[4], &nacl->initiatorname[4], 8);
45 	if (ret) {
46 		pr_debug("%s: invalid hex string\n", __func__);
47 		return ret;
48 	}
49 
50 	return 24;
51 }
52 
53 static int fc_get_pr_transport_id(
54 	struct se_node_acl *se_nacl,
55 	int *format_code,
56 	unsigned char *buf)
57 {
58 	unsigned char *ptr;
59 	int i, ret;
60 	u32 off = 8;
61 
62 	/*
63 	 * We convert the ASCII formatted N Port name into a binary
64 	 * encoded TransportID.
65 	 */
66 	ptr = &se_nacl->initiatorname[0];
67 	for (i = 0; i < 23; ) {
68 		if (!strncmp(&ptr[i], ":", 1)) {
69 			i++;
70 			continue;
71 		}
72 		ret = hex2bin(&buf[off++], &ptr[i], 1);
73 		if (ret < 0) {
74 			pr_debug("%s: invalid hex string\n", __func__);
75 			return ret;
76 		}
77 		i += 2;
78 	}
79 	/*
80 	 * The FC Transport ID is a hardcoded 24-byte length
81 	 */
82 	return 24;
83 }
84 
85 static int sbp_get_pr_transport_id(
86 	struct se_node_acl *nacl,
87 	int *format_code,
88 	unsigned char *buf)
89 {
90 	int ret;
91 
92 	ret = hex2bin(&buf[8], nacl->initiatorname, 8);
93 	if (ret) {
94 		pr_debug("%s: invalid hex string\n", __func__);
95 		return ret;
96 	}
97 
98 	return 24;
99 }
100 
101 static int srp_get_pr_transport_id(
102 	struct se_node_acl *nacl,
103 	int *format_code,
104 	unsigned char *buf)
105 {
106 	const char *p;
107 	unsigned len, count, leading_zero_bytes;
108 	int rc;
109 
110 	p = nacl->initiatorname;
111 	if (strncasecmp(p, "0x", 2) == 0)
112 		p += 2;
113 	len = strlen(p);
114 	if (len % 2)
115 		return -EINVAL;
116 
117 	count = min(len / 2, 16U);
118 	leading_zero_bytes = 16 - count;
119 	memset(buf + 8, 0, leading_zero_bytes);
120 	rc = hex2bin(buf + 8 + leading_zero_bytes, p, count);
121 	if (rc < 0) {
122 		pr_debug("hex2bin failed for %s: %d\n", p, rc);
123 		return rc;
124 	}
125 
126 	return 24;
127 }
128 
129 static int iscsi_get_pr_transport_id(
130 	struct se_node_acl *se_nacl,
131 	struct t10_pr_registration *pr_reg,
132 	int *format_code,
133 	unsigned char *buf)
134 {
135 	u32 off = 4, padding = 0;
136 	int isid_len;
137 	u16 len = 0;
138 
139 	spin_lock_irq(&se_nacl->nacl_sess_lock);
140 	/*
141 	 * Only null terminate the last field.
142 	 *
143 	 * From spc4r37 section 7.6.4.6: TransportID for initiator ports using
144 	 * SCSI over iSCSI.
145 	 *
146 	 * Table 507 TPID=0 Initiator device TransportID
147 	 *
148 	 * The null-terminated, null-padded (see 4.3.2) ISCSI NAME field shall
149 	 * contain the iSCSI name of an iSCSI initiator node (see RFC 7143).
150 	 * The first ISCSI NAME field byte containing an ASCII null character
151 	 * terminates the ISCSI NAME field without regard for the specified
152 	 * length of the iSCSI TransportID or the contents of the ADDITIONAL
153 	 * LENGTH field.
154 	 */
155 	len = sprintf(&buf[off], "%s", se_nacl->initiatorname);
156 	off += len;
157 	if ((*format_code == 1) && (pr_reg->isid_present_at_reg)) {
158 		/*
159 		 * Set FORMAT CODE 01b for iSCSI Initiator port TransportID
160 		 * format.
161 		 */
162 		buf[0] |= 0x40;
163 		/*
164 		 * From spc4r37 Section 7.6.4.6
165 		 *
166 		 * Table 508 TPID=1 Initiator port TransportID.
167 		 *
168 		 * The ISCSI NAME field shall not be null-terminated
169 		 * (see 4.3.2) and shall not be padded.
170 		 *
171 		 * The SEPARATOR field shall contain the five ASCII
172 		 * characters ",i,0x".
173 		 *
174 		 * The null-terminated, null-padded ISCSI INITIATOR SESSION ID
175 		 * field shall contain the iSCSI initiator session identifier
176 		 * (see RFC 3720) in the form of ASCII characters that are the
177 		 * hexadecimal digits converted from the binary iSCSI initiator
178 		 * session identifier value. The first ISCSI INITIATOR SESSION
179 		 * ID field byte containing an ASCII null character terminates
180 		 * the ISCSI INITIATOR SESSION ID field without regard for the
181 		 * specified length of the iSCSI TransportID or the contents
182 		 * of the ADDITIONAL LENGTH field.
183 		 */
184 		buf[off++] = 0x2c; /* ASCII Character: "," */
185 		buf[off++] = 0x69; /* ASCII Character: "i" */
186 		buf[off++] = 0x2c; /* ASCII Character: "," */
187 		buf[off++] = 0x30; /* ASCII Character: "0" */
188 		buf[off++] = 0x78; /* ASCII Character: "x" */
189 		len += 5;
190 
191 		isid_len = sprintf(buf + off, "%s", pr_reg->pr_reg_isid);
192 		off += isid_len;
193 		len += isid_len;
194 	}
195 	buf[off] = '\0';
196 	len += 1;
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 += strlen(pr_reg->pr_reg_isid);
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 void sas_parse_pr_out_transport_id(char *buf, char *i_str)
262 {
263 	char hex[17] = {};
264 
265 	bin2hex(hex, buf + 4, 8);
266 	snprintf(i_str, TRANSPORT_IQN_LEN, "naa.%s", hex);
267 }
268 
269 static void srp_parse_pr_out_transport_id(char *buf, char *i_str)
270 {
271 	char hex[33] = {};
272 
273 	bin2hex(hex, buf + 8, 16);
274 	snprintf(i_str, TRANSPORT_IQN_LEN, "0x%s", hex);
275 }
276 
277 static void fcp_parse_pr_out_transport_id(char *buf, char *i_str)
278 {
279 	snprintf(i_str, TRANSPORT_IQN_LEN, "%8phC", buf + 8);
280 }
281 
282 static void sbp_parse_pr_out_transport_id(char *buf, char *i_str)
283 {
284 	char hex[17] = {};
285 
286 	bin2hex(hex, buf + 8, 8);
287 	snprintf(i_str, TRANSPORT_IQN_LEN, "%s", hex);
288 }
289 
290 static bool iscsi_parse_pr_out_transport_id(
291 	struct se_portal_group *se_tpg,
292 	char *buf,
293 	u32 *out_tid_len,
294 	char **port_nexus_ptr,
295 	char *i_str)
296 {
297 	char *p;
298 	int i;
299 	u8 format_code = (buf[0] & 0xc0);
300 	/*
301 	 * Check for FORMAT CODE 00b or 01b from spc4r17, section 7.5.4.6:
302 	 *
303 	 *       TransportID for initiator ports using SCSI over iSCSI,
304 	 *       from Table 388 -- iSCSI TransportID formats.
305 	 *
306 	 *    00b     Initiator port is identified using the world wide unique
307 	 *            SCSI device name of the iSCSI initiator
308 	 *            device containing the initiator port (see table 389).
309 	 *    01b     Initiator port is identified using the world wide unique
310 	 *            initiator port identifier (see table 390).10b to 11b
311 	 *            Reserved
312 	 */
313 	if ((format_code != 0x00) && (format_code != 0x40)) {
314 		pr_err("Illegal format code: 0x%02x for iSCSI"
315 			" Initiator Transport ID\n", format_code);
316 		return false;
317 	}
318 	/*
319 	 * If the caller wants the TransportID Length, we set that value for the
320 	 * entire iSCSI Tarnsport ID now.
321 	 */
322 	if (out_tid_len) {
323 		/* The shift works thanks to integer promotion rules */
324 		*out_tid_len = get_unaligned_be16(&buf[2]);
325 		/* Add four bytes for iSCSI Transport ID header */
326 		*out_tid_len += 4;
327 	}
328 
329 	/*
330 	 * Check for ',i,0x' separator between iSCSI Name and iSCSI Initiator
331 	 * Session ID as defined in Table 390 - iSCSI initiator port TransportID
332 	 * format.
333 	 */
334 	if (format_code == 0x40) {
335 		p = strstr(&buf[4], ",i,0x");
336 		if (!p) {
337 			pr_err("Unable to locate \",i,0x\" separator"
338 				" for Initiator port identifier: %s\n",
339 				&buf[4]);
340 			return false;
341 		}
342 		*p = '\0'; /* Terminate iSCSI Name */
343 		p += 5; /* Skip over ",i,0x" separator */
344 
345 		*port_nexus_ptr = p;
346 		/*
347 		 * Go ahead and do the lower case conversion of the received
348 		 * 12 ASCII characters representing the ISID in the TransportID
349 		 * for comparison against the running iSCSI session's ISID from
350 		 * iscsi_target.c:lio_sess_get_initiator_sid()
351 		 */
352 		for (i = 0; i < 12; i++) {
353 			/*
354 			 * The first ISCSI INITIATOR SESSION ID field byte
355 			 * containing an ASCII null character terminates the
356 			 * ISCSI INITIATOR SESSION ID field without regard for
357 			 * the specified length of the iSCSI TransportID or the
358 			 * contents of the ADDITIONAL LENGTH field.
359 			 */
360 			if (*p == '\0')
361 				break;
362 
363 			if (isdigit(*p)) {
364 				p++;
365 				continue;
366 			}
367 			*p = tolower(*p);
368 			p++;
369 		}
370 	} else
371 		*port_nexus_ptr = NULL;
372 
373 	strscpy(i_str, &buf[4], TRANSPORT_IQN_LEN);
374 	return true;
375 }
376 
377 int target_get_pr_transport_id_len(struct se_node_acl *nacl,
378 		struct t10_pr_registration *pr_reg, int *format_code)
379 {
380 	switch (nacl->se_tpg->proto_id) {
381 	case SCSI_PROTOCOL_FCP:
382 	case SCSI_PROTOCOL_SBP:
383 	case SCSI_PROTOCOL_SRP:
384 	case SCSI_PROTOCOL_SAS:
385 		break;
386 	case SCSI_PROTOCOL_ISCSI:
387 		return iscsi_get_pr_transport_id_len(nacl, pr_reg, format_code);
388 	default:
389 		pr_err("Unknown proto_id: 0x%02x\n", nacl->se_tpg->proto_id);
390 		return -EINVAL;
391 	}
392 
393 	/*
394 	 * Most transports use a fixed length 24 byte identifier.
395 	 */
396 	*format_code = 0;
397 	return 24;
398 }
399 
400 int target_get_pr_transport_id(struct se_node_acl *nacl,
401 		struct t10_pr_registration *pr_reg, int *format_code,
402 		unsigned char *buf)
403 {
404 	switch (nacl->se_tpg->proto_id) {
405 	case SCSI_PROTOCOL_SAS:
406 		return sas_get_pr_transport_id(nacl, format_code, buf);
407 	case SCSI_PROTOCOL_SBP:
408 		return sbp_get_pr_transport_id(nacl, format_code, buf);
409 	case SCSI_PROTOCOL_SRP:
410 		return srp_get_pr_transport_id(nacl, format_code, buf);
411 	case SCSI_PROTOCOL_FCP:
412 		return fc_get_pr_transport_id(nacl, format_code, buf);
413 	case SCSI_PROTOCOL_ISCSI:
414 		return iscsi_get_pr_transport_id(nacl, pr_reg, format_code,
415 				buf);
416 	default:
417 		pr_err("Unknown proto_id: 0x%02x\n", nacl->se_tpg->proto_id);
418 		return -EINVAL;
419 	}
420 }
421 
422 bool target_parse_pr_out_transport_id(struct se_portal_group *tpg,
423 		char *buf, u32 *out_tid_len, char **port_nexus_ptr, char *i_str)
424 {
425 	switch (tpg->proto_id) {
426 	case SCSI_PROTOCOL_SAS:
427 		/*
428 		 * Assume the FORMAT CODE 00b from spc4r17, 7.5.4.7 TransportID
429 		 * for initiator ports using SCSI over SAS Serial SCSI Protocol.
430 		 */
431 		sas_parse_pr_out_transport_id(buf, i_str);
432 		break;
433 	case SCSI_PROTOCOL_SRP:
434 		srp_parse_pr_out_transport_id(buf, i_str);
435 		break;
436 	case SCSI_PROTOCOL_FCP:
437 		fcp_parse_pr_out_transport_id(buf, i_str);
438 		break;
439 	case SCSI_PROTOCOL_SBP:
440 		sbp_parse_pr_out_transport_id(buf, i_str);
441 		break;
442 	case SCSI_PROTOCOL_ISCSI:
443 		return iscsi_parse_pr_out_transport_id(tpg, buf, out_tid_len,
444 					port_nexus_ptr, i_str);
445 	default:
446 		pr_err("Unknown proto_id: 0x%02x\n", tpg->proto_id);
447 		return false;
448 	}
449 
450 	*port_nexus_ptr = NULL;
451 	*out_tid_len = 24;
452 	return true;
453 }
454