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 2010-2012 RisingTide Systems LLC.
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 #include <linux/kernel.h>
28 #include <linux/string.h>
29 #include <linux/ctype.h>
30 #include <linux/spinlock.h>
31 #include <linux/export.h>
32 #include <scsi/scsi.h>
33 #include <scsi/scsi_cmnd.h>
34 
35 #include <target/target_core_base.h>
36 #include <target/target_core_fabric.h>
37 #include <target/target_core_configfs.h>
38 
39 #include "target_core_internal.h"
40 #include "target_core_pr.h"
41 
42 /*
43  * Handlers for Serial Attached SCSI (SAS)
44  */
45 u8 sas_get_fabric_proto_ident(struct se_portal_group *se_tpg)
46 {
47 	/*
48 	 * Return a SAS Serial SCSI Protocol identifier for loopback operations
49 	 * This is defined in  section 7.5.1 Table 362 in spc4r17
50 	 */
51 	return 0x6;
52 }
53 EXPORT_SYMBOL(sas_get_fabric_proto_ident);
54 
55 u32 sas_get_pr_transport_id(
56 	struct se_portal_group *se_tpg,
57 	struct se_node_acl *se_nacl,
58 	struct t10_pr_registration *pr_reg,
59 	int *format_code,
60 	unsigned char *buf)
61 {
62 	unsigned char *ptr;
63 	int ret;
64 
65 	/*
66 	 * Set PROTOCOL IDENTIFIER to 6h for SAS
67 	 */
68 	buf[0] = 0x06;
69 	/*
70 	 * From spc4r17, 7.5.4.7 TransportID for initiator ports using SCSI
71 	 * over SAS Serial SCSI Protocol
72 	 */
73 	ptr = &se_nacl->initiatorname[4]; /* Skip over 'naa. prefix */
74 
75 	ret = hex2bin(&buf[4], ptr, 8);
76 	if (ret < 0)
77 		pr_debug("sas transport_id: invalid hex string\n");
78 
79 	/*
80 	 * The SAS Transport ID is a hardcoded 24-byte length
81 	 */
82 	return 24;
83 }
84 EXPORT_SYMBOL(sas_get_pr_transport_id);
85 
86 u32 sas_get_pr_transport_id_len(
87 	struct se_portal_group *se_tpg,
88 	struct se_node_acl *se_nacl,
89 	struct t10_pr_registration *pr_reg,
90 	int *format_code)
91 {
92 	*format_code = 0;
93 	/*
94 	 * From spc4r17, 7.5.4.7 TransportID for initiator ports using SCSI
95 	 * over SAS Serial SCSI Protocol
96 	 *
97 	 * The SAS Transport ID is a hardcoded 24-byte length
98 	 */
99 	return 24;
100 }
101 EXPORT_SYMBOL(sas_get_pr_transport_id_len);
102 
103 /*
104  * Used for handling SCSI fabric dependent TransportIDs in SPC-3 and above
105  * Persistent Reservation SPEC_I_PT=1 and PROUT REGISTER_AND_MOVE operations.
106  */
107 char *sas_parse_pr_out_transport_id(
108 	struct se_portal_group *se_tpg,
109 	const char *buf,
110 	u32 *out_tid_len,
111 	char **port_nexus_ptr)
112 {
113 	/*
114 	 * Assume the FORMAT CODE 00b from spc4r17, 7.5.4.7 TransportID
115 	 * for initiator ports using SCSI over SAS Serial SCSI Protocol
116 	 *
117 	 * The TransportID for a SAS Initiator Port is of fixed size of
118 	 * 24 bytes, and SAS does not contain a I_T nexus identifier,
119 	 * so we return the **port_nexus_ptr set to NULL.
120 	 */
121 	*port_nexus_ptr = NULL;
122 	*out_tid_len = 24;
123 
124 	return (char *)&buf[4];
125 }
126 EXPORT_SYMBOL(sas_parse_pr_out_transport_id);
127 
128 /*
129  * Handlers for Fibre Channel Protocol (FCP)
130  */
131 u8 fc_get_fabric_proto_ident(struct se_portal_group *se_tpg)
132 {
133 	return 0x0;	/* 0 = fcp-2 per SPC4 section 7.5.1 */
134 }
135 EXPORT_SYMBOL(fc_get_fabric_proto_ident);
136 
137 u32 fc_get_pr_transport_id_len(
138 	struct se_portal_group *se_tpg,
139 	struct se_node_acl *se_nacl,
140 	struct t10_pr_registration *pr_reg,
141 	int *format_code)
142 {
143 	*format_code = 0;
144 	/*
145 	 * The FC Transport ID is a hardcoded 24-byte length
146 	 */
147 	return 24;
148 }
149 EXPORT_SYMBOL(fc_get_pr_transport_id_len);
150 
151 u32 fc_get_pr_transport_id(
152 	struct se_portal_group *se_tpg,
153 	struct se_node_acl *se_nacl,
154 	struct t10_pr_registration *pr_reg,
155 	int *format_code,
156 	unsigned char *buf)
157 {
158 	unsigned char *ptr;
159 	int i, ret;
160 	u32 off = 8;
161 
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 		ret = hex2bin(&buf[off++], &ptr[i], 1);
179 		if (ret < 0)
180 			pr_debug("fc transport_id: invalid hex string\n");
181 		i += 2;
182 	}
183 	/*
184 	 * The FC Transport ID is a hardcoded 24-byte length
185 	 */
186 	return 24;
187 }
188 EXPORT_SYMBOL(fc_get_pr_transport_id);
189 
190 char *fc_parse_pr_out_transport_id(
191 	struct se_portal_group *se_tpg,
192 	const char *buf,
193 	u32 *out_tid_len,
194 	char **port_nexus_ptr)
195 {
196 	/*
197 	 * The TransportID for a FC N Port is of fixed size of
198 	 * 24 bytes, and FC does not contain a I_T nexus identifier,
199 	 * so we return the **port_nexus_ptr set to NULL.
200 	 */
201 	*port_nexus_ptr = NULL;
202 	*out_tid_len = 24;
203 
204 	 return (char *)&buf[8];
205 }
206 EXPORT_SYMBOL(fc_parse_pr_out_transport_id);
207 
208 /*
209  * Handlers for Internet Small Computer Systems Interface (iSCSI)
210  */
211 
212 u8 iscsi_get_fabric_proto_ident(struct se_portal_group *se_tpg)
213 {
214 	/*
215 	 * This value is defined for "Internet SCSI (iSCSI)"
216 	 * in spc4r17 section 7.5.1 Table 362
217 	 */
218 	return 0x5;
219 }
220 EXPORT_SYMBOL(iscsi_get_fabric_proto_ident);
221 
222 u32 iscsi_get_pr_transport_id(
223 	struct se_portal_group *se_tpg,
224 	struct se_node_acl *se_nacl,
225 	struct t10_pr_registration *pr_reg,
226 	int *format_code,
227 	unsigned char *buf)
228 {
229 	u32 off = 4, padding = 0;
230 	u16 len = 0;
231 
232 	spin_lock_irq(&se_nacl->nacl_sess_lock);
233 	/*
234 	 * Set PROTOCOL IDENTIFIER to 5h for iSCSI
235 	*/
236 	buf[0] = 0x05;
237 	/*
238 	 * From spc4r17 Section 7.5.4.6: TransportID for initiator
239 	 * ports using SCSI over iSCSI.
240 	 *
241 	 * The null-terminated, null-padded (see 4.4.2) ISCSI NAME field
242 	 * shall contain the iSCSI name of an iSCSI initiator node (see
243 	 * RFC 3720). The first ISCSI NAME field byte containing an ASCII
244 	 * null character terminates the ISCSI NAME field without regard for
245 	 * the specified length of the iSCSI TransportID or the contents of
246 	 * the ADDITIONAL LENGTH field.
247 	 */
248 	len = sprintf(&buf[off], "%s", se_nacl->initiatorname);
249 	/*
250 	 * Add Extra byte for NULL terminator
251 	 */
252 	len++;
253 	/*
254 	 * If there is ISID present with the registration and *format code == 1
255 	 * 1, use iSCSI Initiator port TransportID format.
256 	 *
257 	 * Otherwise use iSCSI Initiator device TransportID format that
258 	 * does not contain the ASCII encoded iSCSI Initiator iSID value
259 	 * provied by the iSCSi Initiator during the iSCSI login process.
260 	 */
261 	if ((*format_code == 1) && (pr_reg->isid_present_at_reg)) {
262 		/*
263 		 * Set FORMAT CODE 01b for iSCSI Initiator port TransportID
264 		 * format.
265 		 */
266 		buf[0] |= 0x40;
267 		/*
268 		 * From spc4r17 Section 7.5.4.6: TransportID for initiator
269 		 * ports using SCSI over iSCSI.  Table 390
270 		 *
271 		 * The SEPARATOR field shall contain the five ASCII
272 		 * characters ",i,0x".
273 		 *
274 		 * The null-terminated, null-padded ISCSI INITIATOR SESSION ID
275 		 * field shall contain the iSCSI initiator session identifier
276 		 * (see RFC 3720) in the form of ASCII characters that are the
277 		 * hexadecimal digits converted from the binary iSCSI initiator
278 		 * session identifier value. The first ISCSI INITIATOR SESSION
279 		 * ID field byte containing an ASCII null character
280 		 */
281 		buf[off+len] = 0x2c; off++; /* ASCII Character: "," */
282 		buf[off+len] = 0x69; off++; /* ASCII Character: "i" */
283 		buf[off+len] = 0x2c; off++; /* ASCII Character: "," */
284 		buf[off+len] = 0x30; off++; /* ASCII Character: "0" */
285 		buf[off+len] = 0x78; off++; /* ASCII Character: "x" */
286 		len += 5;
287 		buf[off+len] = pr_reg->pr_reg_isid[0]; off++;
288 		buf[off+len] = pr_reg->pr_reg_isid[1]; off++;
289 		buf[off+len] = pr_reg->pr_reg_isid[2]; off++;
290 		buf[off+len] = pr_reg->pr_reg_isid[3]; off++;
291 		buf[off+len] = pr_reg->pr_reg_isid[4]; off++;
292 		buf[off+len] = pr_reg->pr_reg_isid[5]; off++;
293 		buf[off+len] = '\0'; off++;
294 		len += 7;
295 	}
296 	spin_unlock_irq(&se_nacl->nacl_sess_lock);
297 	/*
298 	 * The ADDITIONAL LENGTH field specifies the number of bytes that follow
299 	 * in the TransportID. The additional length shall be at least 20 and
300 	 * shall be a multiple of four.
301 	*/
302 	padding = ((-len) & 3);
303 	if (padding != 0)
304 		len += padding;
305 
306 	buf[2] = ((len >> 8) & 0xff);
307 	buf[3] = (len & 0xff);
308 	/*
309 	 * Increment value for total payload + header length for
310 	 * full status descriptor
311 	 */
312 	len += 4;
313 
314 	return len;
315 }
316 EXPORT_SYMBOL(iscsi_get_pr_transport_id);
317 
318 u32 iscsi_get_pr_transport_id_len(
319 	struct se_portal_group *se_tpg,
320 	struct se_node_acl *se_nacl,
321 	struct t10_pr_registration *pr_reg,
322 	int *format_code)
323 {
324 	u32 len = 0, padding = 0;
325 
326 	spin_lock_irq(&se_nacl->nacl_sess_lock);
327 	len = strlen(se_nacl->initiatorname);
328 	/*
329 	 * Add extra byte for NULL terminator
330 	 */
331 	len++;
332 	/*
333 	 * If there is ISID present with the registration, use format code:
334 	 * 01b: iSCSI Initiator port TransportID format
335 	 *
336 	 * If there is not an active iSCSI session, use format code:
337 	 * 00b: iSCSI Initiator device TransportID format
338 	 */
339 	if (pr_reg->isid_present_at_reg) {
340 		len += 5; /* For ",i,0x" ASCII separator */
341 		len += 7; /* For iSCSI Initiator Session ID + Null terminator */
342 		*format_code = 1;
343 	} else
344 		*format_code = 0;
345 	spin_unlock_irq(&se_nacl->nacl_sess_lock);
346 	/*
347 	 * The ADDITIONAL LENGTH field specifies the number of bytes that follow
348 	 * in the TransportID. The additional length shall be at least 20 and
349 	 * shall be a multiple of four.
350 	 */
351 	padding = ((-len) & 3);
352 	if (padding != 0)
353 		len += padding;
354 	/*
355 	 * Increment value for total payload + header length for
356 	 * full status descriptor
357 	 */
358 	len += 4;
359 
360 	return len;
361 }
362 EXPORT_SYMBOL(iscsi_get_pr_transport_id_len);
363 
364 char *iscsi_parse_pr_out_transport_id(
365 	struct se_portal_group *se_tpg,
366 	const char *buf,
367 	u32 *out_tid_len,
368 	char **port_nexus_ptr)
369 {
370 	char *p;
371 	u32 tid_len, padding;
372 	int i;
373 	u16 add_len;
374 	u8 format_code = (buf[0] & 0xc0);
375 	/*
376 	 * Check for FORMAT CODE 00b or 01b from spc4r17, section 7.5.4.6:
377 	 *
378 	 *       TransportID for initiator ports using SCSI over iSCSI,
379 	 *       from Table 388 -- iSCSI TransportID formats.
380 	 *
381 	 *    00b     Initiator port is identified using the world wide unique
382 	 *            SCSI device name of the iSCSI initiator
383 	 *            device containing the initiator port (see table 389).
384 	 *    01b     Initiator port is identified using the world wide unique
385 	 *            initiator port identifier (see table 390).10b to 11b
386 	 *            Reserved
387 	 */
388 	if ((format_code != 0x00) && (format_code != 0x40)) {
389 		pr_err("Illegal format code: 0x%02x for iSCSI"
390 			" Initiator Transport ID\n", format_code);
391 		return NULL;
392 	}
393 	/*
394 	 * If the caller wants the TransportID Length, we set that value for the
395 	 * entire iSCSI Tarnsport ID now.
396 	 */
397 	 if (out_tid_len != NULL) {
398 		add_len = ((buf[2] >> 8) & 0xff);
399 		add_len |= (buf[3] & 0xff);
400 
401 		tid_len = strlen(&buf[4]);
402 		tid_len += 4; /* Add four bytes for iSCSI Transport ID header */
403 		tid_len += 1; /* Add one byte for NULL terminator */
404 		padding = ((-tid_len) & 3);
405 		if (padding != 0)
406 			tid_len += padding;
407 
408 		if ((add_len + 4) != tid_len) {
409 			pr_debug("LIO-Target Extracted add_len: %hu "
410 				"does not match calculated tid_len: %u,"
411 				" using tid_len instead\n", add_len+4, tid_len);
412 			*out_tid_len = tid_len;
413 		} else
414 			*out_tid_len = (add_len + 4);
415 	}
416 	/*
417 	 * Check for ',i,0x' separator between iSCSI Name and iSCSI Initiator
418 	 * Session ID as defined in Table 390 - iSCSI initiator port TransportID
419 	 * format.
420 	 */
421 	if (format_code == 0x40) {
422 		p = strstr(&buf[4], ",i,0x");
423 		if (!p) {
424 			pr_err("Unable to locate \",i,0x\" separator"
425 				" for Initiator port identifier: %s\n",
426 				&buf[4]);
427 			return NULL;
428 		}
429 		*p = '\0'; /* Terminate iSCSI Name */
430 		p += 5; /* Skip over ",i,0x" separator */
431 
432 		*port_nexus_ptr = p;
433 		/*
434 		 * Go ahead and do the lower case conversion of the received
435 		 * 12 ASCII characters representing the ISID in the TransportID
436 		 * for comparison against the running iSCSI session's ISID from
437 		 * iscsi_target.c:lio_sess_get_initiator_sid()
438 		 */
439 		for (i = 0; i < 12; i++) {
440 			if (isdigit(*p)) {
441 				p++;
442 				continue;
443 			}
444 			*p = tolower(*p);
445 			p++;
446 		}
447 	}
448 
449 	return (char *)&buf[4];
450 }
451 EXPORT_SYMBOL(iscsi_parse_pr_out_transport_id);
452