xref: /linux/drivers/target/target_core_fabric_lib.c (revision f2ee442115c9b6219083c019939a9cc0c9abb2f8)
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  * Copyright (c) 2010 Rising Tide Systems, Inc.
8  * Copyright (c) 2010 Linux-iSCSI.org
9  *
10  * Nicholas A. Bellinger <nab@linux-iscsi.org>
11  *
12  * This program is free software; you can redistribute it and/or modify
13  * it under the terms of the GNU General Public License as published by
14  * the Free Software Foundation; either version 2 of the License, or
15  * (at your option) any later version.
16  *
17  * This program is distributed in the hope that it will be useful,
18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20  * GNU General Public License for more details.
21  *
22  * You should have received a copy of the GNU General Public License
23  * along with this program; if not, write to the Free Software
24  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
25  *
26  ******************************************************************************/
27 
28 #include <linux/kernel.h>
29 #include <linux/string.h>
30 #include <linux/ctype.h>
31 #include <linux/spinlock.h>
32 #include <linux/export.h>
33 #include <scsi/scsi.h>
34 #include <scsi/scsi_cmnd.h>
35 
36 #include <target/target_core_base.h>
37 #include <target/target_core_device.h>
38 #include <target/target_core_transport.h>
39 #include <target/target_core_fabric_lib.h>
40 #include <target/target_core_fabric_ops.h>
41 #include <target/target_core_configfs.h>
42 
43 #include "target_core_hba.h"
44 #include "target_core_pr.h"
45 
46 /*
47  * Handlers for Serial Attached SCSI (SAS)
48  */
49 u8 sas_get_fabric_proto_ident(struct se_portal_group *se_tpg)
50 {
51 	/*
52 	 * Return a SAS Serial SCSI Protocol identifier for loopback operations
53 	 * This is defined in  section 7.5.1 Table 362 in spc4r17
54 	 */
55 	return 0x6;
56 }
57 EXPORT_SYMBOL(sas_get_fabric_proto_ident);
58 
59 u32 sas_get_pr_transport_id(
60 	struct se_portal_group *se_tpg,
61 	struct se_node_acl *se_nacl,
62 	struct t10_pr_registration *pr_reg,
63 	int *format_code,
64 	unsigned char *buf)
65 {
66 	unsigned char *ptr;
67 	int ret;
68 
69 	/*
70 	 * Set PROTOCOL IDENTIFIER to 6h for SAS
71 	 */
72 	buf[0] = 0x06;
73 	/*
74 	 * From spc4r17, 7.5.4.7 TransportID for initiator ports using SCSI
75 	 * over SAS Serial SCSI Protocol
76 	 */
77 	ptr = &se_nacl->initiatorname[4]; /* Skip over 'naa. prefix */
78 
79 	ret = hex2bin(&buf[4], ptr, 8);
80 	if (ret < 0)
81 		pr_debug("sas transport_id: invalid hex string\n");
82 
83 	/*
84 	 * The SAS Transport ID is a hardcoded 24-byte length
85 	 */
86 	return 24;
87 }
88 EXPORT_SYMBOL(sas_get_pr_transport_id);
89 
90 u32 sas_get_pr_transport_id_len(
91 	struct se_portal_group *se_tpg,
92 	struct se_node_acl *se_nacl,
93 	struct t10_pr_registration *pr_reg,
94 	int *format_code)
95 {
96 	*format_code = 0;
97 	/*
98 	 * From spc4r17, 7.5.4.7 TransportID for initiator ports using SCSI
99 	 * over SAS Serial SCSI Protocol
100 	 *
101 	 * The SAS Transport ID is a hardcoded 24-byte length
102 	 */
103 	return 24;
104 }
105 EXPORT_SYMBOL(sas_get_pr_transport_id_len);
106 
107 /*
108  * Used for handling SCSI fabric dependent TransportIDs in SPC-3 and above
109  * Persistent Reservation SPEC_I_PT=1 and PROUT REGISTER_AND_MOVE operations.
110  */
111 char *sas_parse_pr_out_transport_id(
112 	struct se_portal_group *se_tpg,
113 	const char *buf,
114 	u32 *out_tid_len,
115 	char **port_nexus_ptr)
116 {
117 	/*
118 	 * Assume the FORMAT CODE 00b from spc4r17, 7.5.4.7 TransportID
119 	 * for initiator ports using SCSI over SAS Serial SCSI Protocol
120 	 *
121 	 * The TransportID for a SAS Initiator Port is of fixed size of
122 	 * 24 bytes, and SAS does not contain a I_T nexus identifier,
123 	 * so we return the **port_nexus_ptr set to NULL.
124 	 */
125 	*port_nexus_ptr = NULL;
126 	*out_tid_len = 24;
127 
128 	return (char *)&buf[4];
129 }
130 EXPORT_SYMBOL(sas_parse_pr_out_transport_id);
131 
132 /*
133  * Handlers for Fibre Channel Protocol (FCP)
134  */
135 u8 fc_get_fabric_proto_ident(struct se_portal_group *se_tpg)
136 {
137 	return 0x0;	/* 0 = fcp-2 per SPC4 section 7.5.1 */
138 }
139 EXPORT_SYMBOL(fc_get_fabric_proto_ident);
140 
141 u32 fc_get_pr_transport_id_len(
142 	struct se_portal_group *se_tpg,
143 	struct se_node_acl *se_nacl,
144 	struct t10_pr_registration *pr_reg,
145 	int *format_code)
146 {
147 	*format_code = 0;
148 	/*
149 	 * The FC Transport ID is a hardcoded 24-byte length
150 	 */
151 	return 24;
152 }
153 EXPORT_SYMBOL(fc_get_pr_transport_id_len);
154 
155 u32 fc_get_pr_transport_id(
156 	struct se_portal_group *se_tpg,
157 	struct se_node_acl *se_nacl,
158 	struct t10_pr_registration *pr_reg,
159 	int *format_code,
160 	unsigned char *buf)
161 {
162 	unsigned char *ptr;
163 	int i, ret;
164 	u32 off = 8;
165 
166 	/*
167 	 * PROTOCOL IDENTIFIER is 0h for FCP-2
168 	 *
169 	 * From spc4r17, 7.5.4.2 TransportID for initiator ports using
170 	 * SCSI over Fibre Channel
171 	 *
172 	 * We convert the ASCII formatted N Port name into a binary
173 	 * encoded TransportID.
174 	 */
175 	ptr = &se_nacl->initiatorname[0];
176 
177 	for (i = 0; i < 24; ) {
178 		if (!strncmp(&ptr[i], ":", 1)) {
179 			i++;
180 			continue;
181 		}
182 		ret = hex2bin(&buf[off++], &ptr[i], 1);
183 		if (ret < 0)
184 			pr_debug("fc transport_id: invalid hex string\n");
185 		i += 2;
186 	}
187 	/*
188 	 * The FC Transport ID is a hardcoded 24-byte length
189 	 */
190 	return 24;
191 }
192 EXPORT_SYMBOL(fc_get_pr_transport_id);
193 
194 char *fc_parse_pr_out_transport_id(
195 	struct se_portal_group *se_tpg,
196 	const char *buf,
197 	u32 *out_tid_len,
198 	char **port_nexus_ptr)
199 {
200 	/*
201 	 * The TransportID for a FC N Port is of fixed size of
202 	 * 24 bytes, and FC does not contain a I_T nexus identifier,
203 	 * so we return the **port_nexus_ptr set to NULL.
204 	 */
205 	*port_nexus_ptr = NULL;
206 	*out_tid_len = 24;
207 
208 	 return (char *)&buf[8];
209 }
210 EXPORT_SYMBOL(fc_parse_pr_out_transport_id);
211 
212 /*
213  * Handlers for Internet Small Computer Systems Interface (iSCSI)
214  */
215 
216 u8 iscsi_get_fabric_proto_ident(struct se_portal_group *se_tpg)
217 {
218 	/*
219 	 * This value is defined for "Internet SCSI (iSCSI)"
220 	 * in spc4r17 section 7.5.1 Table 362
221 	 */
222 	return 0x5;
223 }
224 EXPORT_SYMBOL(iscsi_get_fabric_proto_ident);
225 
226 u32 iscsi_get_pr_transport_id(
227 	struct se_portal_group *se_tpg,
228 	struct se_node_acl *se_nacl,
229 	struct t10_pr_registration *pr_reg,
230 	int *format_code,
231 	unsigned char *buf)
232 {
233 	u32 off = 4, padding = 0;
234 	u16 len = 0;
235 
236 	spin_lock_irq(&se_nacl->nacl_sess_lock);
237 	/*
238 	 * Set PROTOCOL IDENTIFIER to 5h for iSCSI
239 	*/
240 	buf[0] = 0x05;
241 	/*
242 	 * From spc4r17 Section 7.5.4.6: TransportID for initiator
243 	 * ports using SCSI over iSCSI.
244 	 *
245 	 * The null-terminated, null-padded (see 4.4.2) ISCSI NAME field
246 	 * shall contain the iSCSI name of an iSCSI initiator node (see
247 	 * RFC 3720). The first ISCSI NAME field byte containing an ASCII
248 	 * null character terminates the ISCSI NAME field without regard for
249 	 * the specified length of the iSCSI TransportID or the contents of
250 	 * the ADDITIONAL LENGTH field.
251 	 */
252 	len = sprintf(&buf[off], "%s", se_nacl->initiatorname);
253 	/*
254 	 * Add Extra byte for NULL terminator
255 	 */
256 	len++;
257 	/*
258 	 * If there is ISID present with the registration and *format code == 1
259 	 * 1, use iSCSI Initiator port TransportID format.
260 	 *
261 	 * Otherwise use iSCSI Initiator device TransportID format that
262 	 * does not contain the ASCII encoded iSCSI Initiator iSID value
263 	 * provied by the iSCSi Initiator during the iSCSI login process.
264 	 */
265 	if ((*format_code == 1) && (pr_reg->isid_present_at_reg)) {
266 		/*
267 		 * Set FORMAT CODE 01b for iSCSI Initiator port TransportID
268 		 * format.
269 		 */
270 		buf[0] |= 0x40;
271 		/*
272 		 * From spc4r17 Section 7.5.4.6: TransportID for initiator
273 		 * ports using SCSI over iSCSI.  Table 390
274 		 *
275 		 * The SEPARATOR field shall contain the five ASCII
276 		 * characters ",i,0x".
277 		 *
278 		 * The null-terminated, null-padded ISCSI INITIATOR SESSION ID
279 		 * field shall contain the iSCSI initiator session identifier
280 		 * (see RFC 3720) in the form of ASCII characters that are the
281 		 * hexadecimal digits converted from the binary iSCSI initiator
282 		 * session identifier value. The first ISCSI INITIATOR SESSION
283 		 * ID field byte containing an ASCII null character
284 		 */
285 		buf[off+len] = 0x2c; off++; /* ASCII Character: "," */
286 		buf[off+len] = 0x69; off++; /* ASCII Character: "i" */
287 		buf[off+len] = 0x2c; off++; /* ASCII Character: "," */
288 		buf[off+len] = 0x30; off++; /* ASCII Character: "0" */
289 		buf[off+len] = 0x78; off++; /* ASCII Character: "x" */
290 		len += 5;
291 		buf[off+len] = pr_reg->pr_reg_isid[0]; off++;
292 		buf[off+len] = pr_reg->pr_reg_isid[1]; off++;
293 		buf[off+len] = pr_reg->pr_reg_isid[2]; off++;
294 		buf[off+len] = pr_reg->pr_reg_isid[3]; off++;
295 		buf[off+len] = pr_reg->pr_reg_isid[4]; off++;
296 		buf[off+len] = pr_reg->pr_reg_isid[5]; off++;
297 		buf[off+len] = '\0'; off++;
298 		len += 7;
299 	}
300 	spin_unlock_irq(&se_nacl->nacl_sess_lock);
301 	/*
302 	 * The ADDITIONAL LENGTH field specifies the number of bytes that follow
303 	 * in the TransportID. The additional length shall be at least 20 and
304 	 * shall be a multiple of four.
305 	*/
306 	padding = ((-len) & 3);
307 	if (padding != 0)
308 		len += padding;
309 
310 	buf[2] = ((len >> 8) & 0xff);
311 	buf[3] = (len & 0xff);
312 	/*
313 	 * Increment value for total payload + header length for
314 	 * full status descriptor
315 	 */
316 	len += 4;
317 
318 	return len;
319 }
320 EXPORT_SYMBOL(iscsi_get_pr_transport_id);
321 
322 u32 iscsi_get_pr_transport_id_len(
323 	struct se_portal_group *se_tpg,
324 	struct se_node_acl *se_nacl,
325 	struct t10_pr_registration *pr_reg,
326 	int *format_code)
327 {
328 	u32 len = 0, padding = 0;
329 
330 	spin_lock_irq(&se_nacl->nacl_sess_lock);
331 	len = strlen(se_nacl->initiatorname);
332 	/*
333 	 * Add extra byte for NULL terminator
334 	 */
335 	len++;
336 	/*
337 	 * If there is ISID present with the registration, use format code:
338 	 * 01b: iSCSI Initiator port TransportID format
339 	 *
340 	 * If there is not an active iSCSI session, use format code:
341 	 * 00b: iSCSI Initiator device TransportID format
342 	 */
343 	if (pr_reg->isid_present_at_reg) {
344 		len += 5; /* For ",i,0x" ASCII seperator */
345 		len += 7; /* For iSCSI Initiator Session ID + Null terminator */
346 		*format_code = 1;
347 	} else
348 		*format_code = 0;
349 	spin_unlock_irq(&se_nacl->nacl_sess_lock);
350 	/*
351 	 * The ADDITIONAL LENGTH field specifies the number of bytes that follow
352 	 * in the TransportID. The additional length shall be at least 20 and
353 	 * shall be a multiple of four.
354 	 */
355 	padding = ((-len) & 3);
356 	if (padding != 0)
357 		len += padding;
358 	/*
359 	 * Increment value for total payload + header length for
360 	 * full status descriptor
361 	 */
362 	len += 4;
363 
364 	return len;
365 }
366 EXPORT_SYMBOL(iscsi_get_pr_transport_id_len);
367 
368 char *iscsi_parse_pr_out_transport_id(
369 	struct se_portal_group *se_tpg,
370 	const char *buf,
371 	u32 *out_tid_len,
372 	char **port_nexus_ptr)
373 {
374 	char *p;
375 	u32 tid_len, padding;
376 	int i;
377 	u16 add_len;
378 	u8 format_code = (buf[0] & 0xc0);
379 	/*
380 	 * Check for FORMAT CODE 00b or 01b from spc4r17, section 7.5.4.6:
381 	 *
382 	 *       TransportID for initiator ports using SCSI over iSCSI,
383 	 *       from Table 388 -- iSCSI TransportID formats.
384 	 *
385 	 *    00b     Initiator port is identified using the world wide unique
386 	 *            SCSI device name of the iSCSI initiator
387 	 *            device containing the initiator port (see table 389).
388 	 *    01b     Initiator port is identified using the world wide unique
389 	 *            initiator port identifier (see table 390).10b to 11b
390 	 *            Reserved
391 	 */
392 	if ((format_code != 0x00) && (format_code != 0x40)) {
393 		pr_err("Illegal format code: 0x%02x for iSCSI"
394 			" Initiator Transport ID\n", format_code);
395 		return NULL;
396 	}
397 	/*
398 	 * If the caller wants the TransportID Length, we set that value for the
399 	 * entire iSCSI Tarnsport ID now.
400 	 */
401 	 if (out_tid_len != NULL) {
402 		add_len = ((buf[2] >> 8) & 0xff);
403 		add_len |= (buf[3] & 0xff);
404 
405 		tid_len = strlen((char *)&buf[4]);
406 		tid_len += 4; /* Add four bytes for iSCSI Transport ID header */
407 		tid_len += 1; /* Add one byte for NULL terminator */
408 		padding = ((-tid_len) & 3);
409 		if (padding != 0)
410 			tid_len += padding;
411 
412 		if ((add_len + 4) != tid_len) {
413 			pr_debug("LIO-Target Extracted add_len: %hu "
414 				"does not match calculated tid_len: %u,"
415 				" using tid_len instead\n", add_len+4, tid_len);
416 			*out_tid_len = tid_len;
417 		} else
418 			*out_tid_len = (add_len + 4);
419 	}
420 	/*
421 	 * Check for ',i,0x' seperator between iSCSI Name and iSCSI Initiator
422 	 * Session ID as defined in Table 390 - iSCSI initiator port TransportID
423 	 * format.
424 	 */
425 	if (format_code == 0x40) {
426 		p = strstr((char *)&buf[4], ",i,0x");
427 		if (!p) {
428 			pr_err("Unable to locate \",i,0x\" seperator"
429 				" for Initiator port identifier: %s\n",
430 				(char *)&buf[4]);
431 			return NULL;
432 		}
433 		*p = '\0'; /* Terminate iSCSI Name */
434 		p += 5; /* Skip over ",i,0x" seperator */
435 
436 		*port_nexus_ptr = p;
437 		/*
438 		 * Go ahead and do the lower case conversion of the received
439 		 * 12 ASCII characters representing the ISID in the TransportID
440 		 * for comparison against the running iSCSI session's ISID from
441 		 * iscsi_target.c:lio_sess_get_initiator_sid()
442 		 */
443 		for (i = 0; i < 12; i++) {
444 			if (isdigit(*p)) {
445 				p++;
446 				continue;
447 			}
448 			*p = tolower(*p);
449 			p++;
450 		}
451 	}
452 
453 	return (char *)&buf[4];
454 }
455 EXPORT_SYMBOL(iscsi_parse_pr_out_transport_id);
456