xref: /linux/drivers/target/target_core_fabric_lib.c (revision 9d9659b6c0ebf7dde65ebada4c67980818245913)
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/string.h>
29 #include <linux/ctype.h>
30 #include <linux/spinlock.h>
31 #include <scsi/scsi.h>
32 #include <scsi/scsi_cmnd.h>
33 
34 #include <target/target_core_base.h>
35 #include <target/target_core_device.h>
36 #include <target/target_core_transport.h>
37 #include <target/target_core_fabric_ops.h>
38 #include <target/target_core_configfs.h>
39 
40 #include "target_core_hba.h"
41 #include "target_core_pr.h"
42 
43 /*
44  * Handlers for Serial Attached SCSI (SAS)
45  */
46 u8 sas_get_fabric_proto_ident(struct se_portal_group *se_tpg)
47 {
48 	/*
49 	 * Return a SAS Serial SCSI Protocol identifier for loopback operations
50 	 * This is defined in  section 7.5.1 Table 362 in spc4r17
51 	 */
52 	return 0x6;
53 }
54 EXPORT_SYMBOL(sas_get_fabric_proto_ident);
55 
56 u32 sas_get_pr_transport_id(
57 	struct se_portal_group *se_tpg,
58 	struct se_node_acl *se_nacl,
59 	struct t10_pr_registration *pr_reg,
60 	int *format_code,
61 	unsigned char *buf)
62 {
63 	unsigned char binary, *ptr;
64 	int i;
65 	u32 off = 4;
66 	/*
67 	 * Set PROTOCOL IDENTIFIER to 6h for SAS
68 	 */
69 	buf[0] = 0x06;
70 	/*
71 	 * From spc4r17, 7.5.4.7 TransportID for initiator ports using SCSI
72 	 * over SAS Serial SCSI Protocol
73 	 */
74 	ptr = &se_nacl->initiatorname[4]; /* Skip over 'naa. prefix */
75 
76 	for (i = 0; i < 16; i += 2) {
77 		binary = transport_asciihex_to_binaryhex(&ptr[i]);
78 		buf[off++] = binary;
79 	}
80 	/*
81 	 * The SAS Transport ID is a hardcoded 24-byte length
82 	 */
83 	return 24;
84 }
85 EXPORT_SYMBOL(sas_get_pr_transport_id);
86 
87 u32 sas_get_pr_transport_id_len(
88 	struct se_portal_group *se_tpg,
89 	struct se_node_acl *se_nacl,
90 	struct t10_pr_registration *pr_reg,
91 	int *format_code)
92 {
93 	*format_code = 0;
94 	/*
95 	 * From spc4r17, 7.5.4.7 TransportID for initiator ports using SCSI
96 	 * over SAS Serial SCSI Protocol
97 	 *
98 	 * The SAS Transport ID is a hardcoded 24-byte length
99 	 */
100 	return 24;
101 }
102 EXPORT_SYMBOL(sas_get_pr_transport_id_len);
103 
104 /*
105  * Used for handling SCSI fabric dependent TransportIDs in SPC-3 and above
106  * Persistent Reservation SPEC_I_PT=1 and PROUT REGISTER_AND_MOVE operations.
107  */
108 char *sas_parse_pr_out_transport_id(
109 	struct se_portal_group *se_tpg,
110 	const char *buf,
111 	u32 *out_tid_len,
112 	char **port_nexus_ptr)
113 {
114 	/*
115 	 * Assume the FORMAT CODE 00b from spc4r17, 7.5.4.7 TransportID
116 	 * for initiator ports using SCSI over SAS Serial SCSI Protocol
117 	 *
118 	 * The TransportID for a SAS Initiator Port is of fixed size of
119 	 * 24 bytes, and SAS does not contain a I_T nexus identifier,
120 	 * so we return the **port_nexus_ptr set to NULL.
121 	 */
122 	*port_nexus_ptr = NULL;
123 	*out_tid_len = 24;
124 
125 	return (char *)&buf[4];
126 }
127 EXPORT_SYMBOL(sas_parse_pr_out_transport_id);
128 
129 /*
130  * Handlers for Fibre Channel Protocol (FCP)
131  */
132 u8 fc_get_fabric_proto_ident(struct se_portal_group *se_tpg)
133 {
134 	return 0x0;	/* 0 = fcp-2 per SPC4 section 7.5.1 */
135 }
136 EXPORT_SYMBOL(fc_get_fabric_proto_ident);
137 
138 u32 fc_get_pr_transport_id_len(
139 	struct se_portal_group *se_tpg,
140 	struct se_node_acl *se_nacl,
141 	struct t10_pr_registration *pr_reg,
142 	int *format_code)
143 {
144 	*format_code = 0;
145 	/*
146 	 * The FC Transport ID is a hardcoded 24-byte length
147 	 */
148 	return 24;
149 }
150 EXPORT_SYMBOL(fc_get_pr_transport_id_len);
151 
152 u32 fc_get_pr_transport_id(
153 	struct se_portal_group *se_tpg,
154 	struct se_node_acl *se_nacl,
155 	struct t10_pr_registration *pr_reg,
156 	int *format_code,
157 	unsigned char *buf)
158 {
159 	unsigned char binary, *ptr;
160 	int i;
161 	u32 off = 8;
162 	/*
163 	 * PROTOCOL IDENTIFIER is 0h for FCP-2
164 	 *
165 	 * From spc4r17, 7.5.4.2 TransportID for initiator ports using
166 	 * SCSI over Fibre Channel
167 	 *
168 	 * We convert the ASCII formatted N Port name into a binary
169 	 * encoded TransportID.
170 	 */
171 	ptr = &se_nacl->initiatorname[0];
172 
173 	for (i = 0; i < 24; ) {
174 		if (!(strncmp(&ptr[i], ":", 1))) {
175 			i++;
176 			continue;
177 		}
178 		binary = transport_asciihex_to_binaryhex(&ptr[i]);
179 		buf[off++] = binary;
180 		i += 2;
181 	}
182 	/*
183 	 * The FC Transport ID is a hardcoded 24-byte length
184 	 */
185 	return 24;
186 }
187 EXPORT_SYMBOL(fc_get_pr_transport_id);
188 
189 char *fc_parse_pr_out_transport_id(
190 	struct se_portal_group *se_tpg,
191 	const char *buf,
192 	u32 *out_tid_len,
193 	char **port_nexus_ptr)
194 {
195 	/*
196 	 * The TransportID for a FC N Port is of fixed size of
197 	 * 24 bytes, and FC does not contain a I_T nexus identifier,
198 	 * so we return the **port_nexus_ptr set to NULL.
199 	 */
200 	*port_nexus_ptr = NULL;
201 	*out_tid_len = 24;
202 
203 	 return (char *)&buf[8];
204 }
205 EXPORT_SYMBOL(fc_parse_pr_out_transport_id);
206 
207 /*
208  * Handlers for Internet Small Computer Systems Interface (iSCSI)
209  */
210 
211 u8 iscsi_get_fabric_proto_ident(struct se_portal_group *se_tpg)
212 {
213 	/*
214 	 * This value is defined for "Internet SCSI (iSCSI)"
215 	 * in spc4r17 section 7.5.1 Table 362
216 	 */
217 	return 0x5;
218 }
219 EXPORT_SYMBOL(iscsi_get_fabric_proto_ident);
220 
221 u32 iscsi_get_pr_transport_id(
222 	struct se_portal_group *se_tpg,
223 	struct se_node_acl *se_nacl,
224 	struct t10_pr_registration *pr_reg,
225 	int *format_code,
226 	unsigned char *buf)
227 {
228 	u32 off = 4, padding = 0;
229 	u16 len = 0;
230 
231 	spin_lock_irq(&se_nacl->nacl_sess_lock);
232 	/*
233 	 * Set PROTOCOL IDENTIFIER to 5h for iSCSI
234 	*/
235 	buf[0] = 0x05;
236 	/*
237 	 * From spc4r17 Section 7.5.4.6: TransportID for initiator
238 	 * ports using SCSI over iSCSI.
239 	 *
240 	 * The null-terminated, null-padded (see 4.4.2) ISCSI NAME field
241 	 * shall contain the iSCSI name of an iSCSI initiator node (see
242 	 * RFC 3720). The first ISCSI NAME field byte containing an ASCII
243 	 * null character terminates the ISCSI NAME field without regard for
244 	 * the specified length of the iSCSI TransportID or the contents of
245 	 * the ADDITIONAL LENGTH field.
246 	 */
247 	len = sprintf(&buf[off], "%s", se_nacl->initiatorname);
248 	/*
249 	 * Add Extra byte for NULL terminator
250 	 */
251 	len++;
252 	/*
253 	 * If there is ISID present with the registration and *format code == 1
254 	 * 1, use iSCSI Initiator port TransportID format.
255 	 *
256 	 * Otherwise use iSCSI Initiator device TransportID format that
257 	 * does not contain the ASCII encoded iSCSI Initiator iSID value
258 	 * provied by the iSCSi Initiator during the iSCSI login process.
259 	 */
260 	if ((*format_code == 1) && (pr_reg->isid_present_at_reg)) {
261 		/*
262 		 * Set FORMAT CODE 01b for iSCSI Initiator port TransportID
263 		 * format.
264 		 */
265 		buf[0] |= 0x40;
266 		/*
267 		 * From spc4r17 Section 7.5.4.6: TransportID for initiator
268 		 * ports using SCSI over iSCSI.  Table 390
269 		 *
270 		 * The SEPARATOR field shall contain the five ASCII
271 		 * characters ",i,0x".
272 		 *
273 		 * The null-terminated, null-padded ISCSI INITIATOR SESSION ID
274 		 * field shall contain the iSCSI initiator session identifier
275 		 * (see RFC 3720) in the form of ASCII characters that are the
276 		 * hexadecimal digits converted from the binary iSCSI initiator
277 		 * session identifier value. The first ISCSI INITIATOR SESSION
278 		 * ID field byte containing an ASCII null character
279 		 */
280 		buf[off+len] = 0x2c; off++; /* ASCII Character: "," */
281 		buf[off+len] = 0x69; off++; /* ASCII Character: "i" */
282 		buf[off+len] = 0x2c; off++; /* ASCII Character: "," */
283 		buf[off+len] = 0x30; off++; /* ASCII Character: "0" */
284 		buf[off+len] = 0x78; off++; /* ASCII Character: "x" */
285 		len += 5;
286 		buf[off+len] = pr_reg->pr_reg_isid[0]; off++;
287 		buf[off+len] = pr_reg->pr_reg_isid[1]; off++;
288 		buf[off+len] = pr_reg->pr_reg_isid[2]; off++;
289 		buf[off+len] = pr_reg->pr_reg_isid[3]; off++;
290 		buf[off+len] = pr_reg->pr_reg_isid[4]; off++;
291 		buf[off+len] = pr_reg->pr_reg_isid[5]; off++;
292 		buf[off+len] = '\0'; off++;
293 		len += 7;
294 	}
295 	spin_unlock_irq(&se_nacl->nacl_sess_lock);
296 	/*
297 	 * The ADDITIONAL LENGTH field specifies the number of bytes that follow
298 	 * in the TransportID. The additional length shall be at least 20 and
299 	 * shall be a multiple of four.
300 	*/
301 	padding = ((-len) & 3);
302 	if (padding != 0)
303 		len += padding;
304 
305 	buf[2] = ((len >> 8) & 0xff);
306 	buf[3] = (len & 0xff);
307 	/*
308 	 * Increment value for total payload + header length for
309 	 * full status descriptor
310 	 */
311 	len += 4;
312 
313 	return len;
314 }
315 EXPORT_SYMBOL(iscsi_get_pr_transport_id);
316 
317 u32 iscsi_get_pr_transport_id_len(
318 	struct se_portal_group *se_tpg,
319 	struct se_node_acl *se_nacl,
320 	struct t10_pr_registration *pr_reg,
321 	int *format_code)
322 {
323 	u32 len = 0, padding = 0;
324 
325 	spin_lock_irq(&se_nacl->nacl_sess_lock);
326 	len = strlen(se_nacl->initiatorname);
327 	/*
328 	 * Add extra byte for NULL terminator
329 	 */
330 	len++;
331 	/*
332 	 * If there is ISID present with the registration, use format code:
333 	 * 01b: iSCSI Initiator port TransportID format
334 	 *
335 	 * If there is not an active iSCSI session, use format code:
336 	 * 00b: iSCSI Initiator device TransportID format
337 	 */
338 	if (pr_reg->isid_present_at_reg) {
339 		len += 5; /* For ",i,0x" ASCII seperator */
340 		len += 7; /* For iSCSI Initiator Session ID + Null terminator */
341 		*format_code = 1;
342 	} else
343 		*format_code = 0;
344 	spin_unlock_irq(&se_nacl->nacl_sess_lock);
345 	/*
346 	 * The ADDITIONAL LENGTH field specifies the number of bytes that follow
347 	 * in the TransportID. The additional length shall be at least 20 and
348 	 * shall be a multiple of four.
349 	 */
350 	padding = ((-len) & 3);
351 	if (padding != 0)
352 		len += padding;
353 	/*
354 	 * Increment value for total payload + header length for
355 	 * full status descriptor
356 	 */
357 	len += 4;
358 
359 	return len;
360 }
361 EXPORT_SYMBOL(iscsi_get_pr_transport_id_len);
362 
363 char *iscsi_parse_pr_out_transport_id(
364 	struct se_portal_group *se_tpg,
365 	const char *buf,
366 	u32 *out_tid_len,
367 	char **port_nexus_ptr)
368 {
369 	char *p;
370 	u32 tid_len, padding;
371 	int i;
372 	u16 add_len;
373 	u8 format_code = (buf[0] & 0xc0);
374 	/*
375 	 * Check for FORMAT CODE 00b or 01b from spc4r17, section 7.5.4.6:
376 	 *
377 	 *       TransportID for initiator ports using SCSI over iSCSI,
378 	 *       from Table 388 -- iSCSI TransportID formats.
379 	 *
380 	 *    00b     Initiator port is identified using the world wide unique
381 	 *            SCSI device name of the iSCSI initiator
382 	 *            device containing the initiator port (see table 389).
383 	 *    01b     Initiator port is identified using the world wide unique
384 	 *            initiator port identifier (see table 390).10b to 11b
385 	 *            Reserved
386 	 */
387 	if ((format_code != 0x00) && (format_code != 0x40)) {
388 		printk(KERN_ERR "Illegal format code: 0x%02x for iSCSI"
389 			" Initiator Transport ID\n", format_code);
390 		return NULL;
391 	}
392 	/*
393 	 * If the caller wants the TransportID Length, we set that value for the
394 	 * entire iSCSI Tarnsport ID now.
395 	 */
396 	 if (out_tid_len != NULL) {
397 		add_len = ((buf[2] >> 8) & 0xff);
398 		add_len |= (buf[3] & 0xff);
399 
400 		tid_len = strlen((char *)&buf[4]);
401 		tid_len += 4; /* Add four bytes for iSCSI Transport ID header */
402 		tid_len += 1; /* Add one byte for NULL terminator */
403 		padding = ((-tid_len) & 3);
404 		if (padding != 0)
405 			tid_len += padding;
406 
407 		if ((add_len + 4) != tid_len) {
408 			printk(KERN_INFO "LIO-Target Extracted add_len: %hu "
409 				"does not match calculated tid_len: %u,"
410 				" using tid_len instead\n", add_len+4, tid_len);
411 			*out_tid_len = tid_len;
412 		} else
413 			*out_tid_len = (add_len + 4);
414 	}
415 	/*
416 	 * Check for ',i,0x' seperator between iSCSI Name and iSCSI Initiator
417 	 * Session ID as defined in Table 390 - iSCSI initiator port TransportID
418 	 * format.
419 	 */
420 	if (format_code == 0x40) {
421 		p = strstr((char *)&buf[4], ",i,0x");
422 		if (!(p)) {
423 			printk(KERN_ERR "Unable to locate \",i,0x\" seperator"
424 				" for Initiator port identifier: %s\n",
425 				(char *)&buf[4]);
426 			return NULL;
427 		}
428 		*p = '\0'; /* Terminate iSCSI Name */
429 		p += 5; /* Skip over ",i,0x" seperator */
430 
431 		*port_nexus_ptr = p;
432 		/*
433 		 * Go ahead and do the lower case conversion of the received
434 		 * 12 ASCII characters representing the ISID in the TransportID
435 		 * for comparision against the running iSCSI session's ISID from
436 		 * iscsi_target.c:lio_sess_get_initiator_sid()
437 		 */
438 		for (i = 0; i < 12; i++) {
439 			if (isdigit(*p)) {
440 				p++;
441 				continue;
442 			}
443 			*p = tolower(*p);
444 			p++;
445 		}
446 	}
447 
448 	return (char *)&buf[4];
449 }
450 EXPORT_SYMBOL(iscsi_parse_pr_out_transport_id);
451