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 2010-2013 Datera, Inc.
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 
33 #include <target/target_core_base.h>
34 #include <target/target_core_fabric.h>
35 #include <target/target_core_configfs.h>
36 
37 #include "target_core_internal.h"
38 #include "target_core_pr.h"
39 
40 /*
41  * Handlers for Serial Attached SCSI (SAS)
42  */
43 u8 sas_get_fabric_proto_ident(struct se_portal_group *se_tpg)
44 {
45 	/*
46 	 * Return a SAS Serial SCSI Protocol identifier for loopback operations
47 	 * This is defined in  section 7.5.1 Table 362 in spc4r17
48 	 */
49 	return 0x6;
50 }
51 EXPORT_SYMBOL(sas_get_fabric_proto_ident);
52 
53 u32 sas_get_pr_transport_id(
54 	struct se_portal_group *se_tpg,
55 	struct se_node_acl *se_nacl,
56 	struct t10_pr_registration *pr_reg,
57 	int *format_code,
58 	unsigned char *buf)
59 {
60 	unsigned char *ptr;
61 	int ret;
62 
63 	/*
64 	 * Set PROTOCOL IDENTIFIER to 6h for SAS
65 	 */
66 	buf[0] = 0x06;
67 	/*
68 	 * From spc4r17, 7.5.4.7 TransportID for initiator ports using SCSI
69 	 * over SAS Serial SCSI Protocol
70 	 */
71 	ptr = &se_nacl->initiatorname[4]; /* Skip over 'naa. prefix */
72 
73 	ret = hex2bin(&buf[4], ptr, 8);
74 	if (ret < 0)
75 		pr_debug("sas transport_id: invalid hex string\n");
76 
77 	/*
78 	 * The SAS Transport ID is a hardcoded 24-byte length
79 	 */
80 	return 24;
81 }
82 EXPORT_SYMBOL(sas_get_pr_transport_id);
83 
84 u32 sas_get_pr_transport_id_len(
85 	struct se_portal_group *se_tpg,
86 	struct se_node_acl *se_nacl,
87 	struct t10_pr_registration *pr_reg,
88 	int *format_code)
89 {
90 	*format_code = 0;
91 	/*
92 	 * From spc4r17, 7.5.4.7 TransportID for initiator ports using SCSI
93 	 * over SAS Serial SCSI Protocol
94 	 *
95 	 * The SAS Transport ID is a hardcoded 24-byte length
96 	 */
97 	return 24;
98 }
99 EXPORT_SYMBOL(sas_get_pr_transport_id_len);
100 
101 /*
102  * Used for handling SCSI fabric dependent TransportIDs in SPC-3 and above
103  * Persistent Reservation SPEC_I_PT=1 and PROUT REGISTER_AND_MOVE operations.
104  */
105 char *sas_parse_pr_out_transport_id(
106 	struct se_portal_group *se_tpg,
107 	const char *buf,
108 	u32 *out_tid_len,
109 	char **port_nexus_ptr)
110 {
111 	/*
112 	 * Assume the FORMAT CODE 00b from spc4r17, 7.5.4.7 TransportID
113 	 * for initiator ports using SCSI over SAS Serial SCSI Protocol
114 	 *
115 	 * The TransportID for a SAS Initiator Port is of fixed size of
116 	 * 24 bytes, and SAS does not contain a I_T nexus identifier,
117 	 * so we return the **port_nexus_ptr set to NULL.
118 	 */
119 	*port_nexus_ptr = NULL;
120 	*out_tid_len = 24;
121 
122 	return (char *)&buf[4];
123 }
124 EXPORT_SYMBOL(sas_parse_pr_out_transport_id);
125 
126 /*
127  * Handlers for Fibre Channel Protocol (FCP)
128  */
129 u8 fc_get_fabric_proto_ident(struct se_portal_group *se_tpg)
130 {
131 	return 0x0;	/* 0 = fcp-2 per SPC4 section 7.5.1 */
132 }
133 EXPORT_SYMBOL(fc_get_fabric_proto_ident);
134 
135 u32 fc_get_pr_transport_id_len(
136 	struct se_portal_group *se_tpg,
137 	struct se_node_acl *se_nacl,
138 	struct t10_pr_registration *pr_reg,
139 	int *format_code)
140 {
141 	*format_code = 0;
142 	/*
143 	 * The FC Transport ID is a hardcoded 24-byte length
144 	 */
145 	return 24;
146 }
147 EXPORT_SYMBOL(fc_get_pr_transport_id_len);
148 
149 u32 fc_get_pr_transport_id(
150 	struct se_portal_group *se_tpg,
151 	struct se_node_acl *se_nacl,
152 	struct t10_pr_registration *pr_reg,
153 	int *format_code,
154 	unsigned char *buf)
155 {
156 	unsigned char *ptr;
157 	int i, ret;
158 	u32 off = 8;
159 
160 	/*
161 	 * PROTOCOL IDENTIFIER is 0h for FCP-2
162 	 *
163 	 * From spc4r17, 7.5.4.2 TransportID for initiator ports using
164 	 * SCSI over Fibre Channel
165 	 *
166 	 * We convert the ASCII formatted N Port name into a binary
167 	 * encoded TransportID.
168 	 */
169 	ptr = &se_nacl->initiatorname[0];
170 
171 	for (i = 0; i < 24; ) {
172 		if (!strncmp(&ptr[i], ":", 1)) {
173 			i++;
174 			continue;
175 		}
176 		ret = hex2bin(&buf[off++], &ptr[i], 1);
177 		if (ret < 0)
178 			pr_debug("fc transport_id: invalid hex string\n");
179 		i += 2;
180 	}
181 	/*
182 	 * The FC Transport ID is a hardcoded 24-byte length
183 	 */
184 	return 24;
185 }
186 EXPORT_SYMBOL(fc_get_pr_transport_id);
187 
188 char *fc_parse_pr_out_transport_id(
189 	struct se_portal_group *se_tpg,
190 	const char *buf,
191 	u32 *out_tid_len,
192 	char **port_nexus_ptr)
193 {
194 	/*
195 	 * The TransportID for a FC N Port is of fixed size of
196 	 * 24 bytes, and FC does not contain a I_T nexus identifier,
197 	 * so we return the **port_nexus_ptr set to NULL.
198 	 */
199 	*port_nexus_ptr = NULL;
200 	*out_tid_len = 24;
201 
202 	 return (char *)&buf[8];
203 }
204 EXPORT_SYMBOL(fc_parse_pr_out_transport_id);
205 
206 /*
207  * Handlers for Internet Small Computer Systems Interface (iSCSI)
208  */
209 
210 u8 iscsi_get_fabric_proto_ident(struct se_portal_group *se_tpg)
211 {
212 	/*
213 	 * This value is defined for "Internet SCSI (iSCSI)"
214 	 * in spc4r17 section 7.5.1 Table 362
215 	 */
216 	return 0x5;
217 }
218 EXPORT_SYMBOL(iscsi_get_fabric_proto_ident);
219 
220 u32 iscsi_get_pr_transport_id(
221 	struct se_portal_group *se_tpg,
222 	struct se_node_acl *se_nacl,
223 	struct t10_pr_registration *pr_reg,
224 	int *format_code,
225 	unsigned char *buf)
226 {
227 	u32 off = 4, padding = 0;
228 	u16 len = 0;
229 
230 	spin_lock_irq(&se_nacl->nacl_sess_lock);
231 	/*
232 	 * Set PROTOCOL IDENTIFIER to 5h for iSCSI
233 	*/
234 	buf[0] = 0x05;
235 	/*
236 	 * From spc4r17 Section 7.5.4.6: TransportID for initiator
237 	 * ports using SCSI over iSCSI.
238 	 *
239 	 * The null-terminated, null-padded (see 4.4.2) ISCSI NAME field
240 	 * shall contain the iSCSI name of an iSCSI initiator node (see
241 	 * RFC 3720). The first ISCSI NAME field byte containing an ASCII
242 	 * null character terminates the ISCSI NAME field without regard for
243 	 * the specified length of the iSCSI TransportID or the contents of
244 	 * the ADDITIONAL LENGTH field.
245 	 */
246 	len = sprintf(&buf[off], "%s", se_nacl->initiatorname);
247 	/*
248 	 * Add Extra byte for NULL terminator
249 	 */
250 	len++;
251 	/*
252 	 * If there is ISID present with the registration and *format code == 1
253 	 * 1, use iSCSI Initiator port TransportID format.
254 	 *
255 	 * Otherwise use iSCSI Initiator device TransportID format that
256 	 * does not contain the ASCII encoded iSCSI Initiator iSID value
257 	 * provied by the iSCSi Initiator during the iSCSI login process.
258 	 */
259 	if ((*format_code == 1) && (pr_reg->isid_present_at_reg)) {
260 		/*
261 		 * Set FORMAT CODE 01b for iSCSI Initiator port TransportID
262 		 * format.
263 		 */
264 		buf[0] |= 0x40;
265 		/*
266 		 * From spc4r17 Section 7.5.4.6: TransportID for initiator
267 		 * ports using SCSI over iSCSI.  Table 390
268 		 *
269 		 * The SEPARATOR field shall contain the five ASCII
270 		 * characters ",i,0x".
271 		 *
272 		 * The null-terminated, null-padded ISCSI INITIATOR SESSION ID
273 		 * field shall contain the iSCSI initiator session identifier
274 		 * (see RFC 3720) in the form of ASCII characters that are the
275 		 * hexadecimal digits converted from the binary iSCSI initiator
276 		 * session identifier value. The first ISCSI INITIATOR SESSION
277 		 * ID field byte containing an ASCII null character
278 		 */
279 		buf[off+len] = 0x2c; off++; /* ASCII Character: "," */
280 		buf[off+len] = 0x69; off++; /* ASCII Character: "i" */
281 		buf[off+len] = 0x2c; off++; /* ASCII Character: "," */
282 		buf[off+len] = 0x30; off++; /* ASCII Character: "0" */
283 		buf[off+len] = 0x78; off++; /* ASCII Character: "x" */
284 		len += 5;
285 		buf[off+len] = pr_reg->pr_reg_isid[0]; off++;
286 		buf[off+len] = pr_reg->pr_reg_isid[1]; off++;
287 		buf[off+len] = pr_reg->pr_reg_isid[2]; off++;
288 		buf[off+len] = pr_reg->pr_reg_isid[3]; off++;
289 		buf[off+len] = pr_reg->pr_reg_isid[4]; off++;
290 		buf[off+len] = pr_reg->pr_reg_isid[5]; off++;
291 		buf[off+len] = '\0'; off++;
292 		len += 7;
293 	}
294 	spin_unlock_irq(&se_nacl->nacl_sess_lock);
295 	/*
296 	 * The ADDITIONAL LENGTH field specifies the number of bytes that follow
297 	 * in the TransportID. The additional length shall be at least 20 and
298 	 * shall be a multiple of four.
299 	*/
300 	padding = ((-len) & 3);
301 	if (padding != 0)
302 		len += padding;
303 
304 	buf[2] = ((len >> 8) & 0xff);
305 	buf[3] = (len & 0xff);
306 	/*
307 	 * Increment value for total payload + header length for
308 	 * full status descriptor
309 	 */
310 	len += 4;
311 
312 	return len;
313 }
314 EXPORT_SYMBOL(iscsi_get_pr_transport_id);
315 
316 u32 iscsi_get_pr_transport_id_len(
317 	struct se_portal_group *se_tpg,
318 	struct se_node_acl *se_nacl,
319 	struct t10_pr_registration *pr_reg,
320 	int *format_code)
321 {
322 	u32 len = 0, padding = 0;
323 
324 	spin_lock_irq(&se_nacl->nacl_sess_lock);
325 	len = strlen(se_nacl->initiatorname);
326 	/*
327 	 * Add extra byte for NULL terminator
328 	 */
329 	len++;
330 	/*
331 	 * If there is ISID present with the registration, use format code:
332 	 * 01b: iSCSI Initiator port TransportID format
333 	 *
334 	 * If there is not an active iSCSI session, use format code:
335 	 * 00b: iSCSI Initiator device TransportID format
336 	 */
337 	if (pr_reg->isid_present_at_reg) {
338 		len += 5; /* For ",i,0x" ASCII separator */
339 		len += 7; /* For iSCSI Initiator Session ID + Null terminator */
340 		*format_code = 1;
341 	} else
342 		*format_code = 0;
343 	spin_unlock_irq(&se_nacl->nacl_sess_lock);
344 	/*
345 	 * The ADDITIONAL LENGTH field specifies the number of bytes that follow
346 	 * in the TransportID. The additional length shall be at least 20 and
347 	 * shall be a multiple of four.
348 	 */
349 	padding = ((-len) & 3);
350 	if (padding != 0)
351 		len += padding;
352 	/*
353 	 * Increment value for total payload + header length for
354 	 * full status descriptor
355 	 */
356 	len += 4;
357 
358 	return len;
359 }
360 EXPORT_SYMBOL(iscsi_get_pr_transport_id_len);
361 
362 char *iscsi_parse_pr_out_transport_id(
363 	struct se_portal_group *se_tpg,
364 	const char *buf,
365 	u32 *out_tid_len,
366 	char **port_nexus_ptr)
367 {
368 	char *p;
369 	u32 tid_len, padding;
370 	int i;
371 	u16 add_len;
372 	u8 format_code = (buf[0] & 0xc0);
373 	/*
374 	 * Check for FORMAT CODE 00b or 01b from spc4r17, section 7.5.4.6:
375 	 *
376 	 *       TransportID for initiator ports using SCSI over iSCSI,
377 	 *       from Table 388 -- iSCSI TransportID formats.
378 	 *
379 	 *    00b     Initiator port is identified using the world wide unique
380 	 *            SCSI device name of the iSCSI initiator
381 	 *            device containing the initiator port (see table 389).
382 	 *    01b     Initiator port is identified using the world wide unique
383 	 *            initiator port identifier (see table 390).10b to 11b
384 	 *            Reserved
385 	 */
386 	if ((format_code != 0x00) && (format_code != 0x40)) {
387 		pr_err("Illegal format code: 0x%02x for iSCSI"
388 			" Initiator Transport ID\n", format_code);
389 		return NULL;
390 	}
391 	/*
392 	 * If the caller wants the TransportID Length, we set that value for the
393 	 * entire iSCSI Tarnsport ID now.
394 	 */
395 	if (out_tid_len) {
396 		/* The shift works thanks to integer promotion rules */
397 		add_len = (buf[2] << 8) | buf[3];
398 
399 		tid_len = strlen(&buf[4]);
400 		tid_len += 4; /* Add four bytes for iSCSI Transport ID header */
401 		tid_len += 1; /* Add one byte for NULL terminator */
402 		padding = ((-tid_len) & 3);
403 		if (padding != 0)
404 			tid_len += padding;
405 
406 		if ((add_len + 4) != tid_len) {
407 			pr_debug("LIO-Target Extracted add_len: %hu "
408 				"does not match calculated tid_len: %u,"
409 				" using tid_len instead\n", add_len+4, tid_len);
410 			*out_tid_len = tid_len;
411 		} else
412 			*out_tid_len = (add_len + 4);
413 	}
414 	/*
415 	 * Check for ',i,0x' separator between iSCSI Name and iSCSI Initiator
416 	 * Session ID as defined in Table 390 - iSCSI initiator port TransportID
417 	 * format.
418 	 */
419 	if (format_code == 0x40) {
420 		p = strstr(&buf[4], ",i,0x");
421 		if (!p) {
422 			pr_err("Unable to locate \",i,0x\" separator"
423 				" for Initiator port identifier: %s\n",
424 				&buf[4]);
425 			return NULL;
426 		}
427 		*p = '\0'; /* Terminate iSCSI Name */
428 		p += 5; /* Skip over ",i,0x" separator */
429 
430 		*port_nexus_ptr = p;
431 		/*
432 		 * Go ahead and do the lower case conversion of the received
433 		 * 12 ASCII characters representing the ISID in the TransportID
434 		 * for comparison against the running iSCSI session's ISID from
435 		 * iscsi_target.c:lio_sess_get_initiator_sid()
436 		 */
437 		for (i = 0; i < 12; i++) {
438 			if (isdigit(*p)) {
439 				p++;
440 				continue;
441 			}
442 			*p = tolower(*p);
443 			p++;
444 		}
445 	}
446 
447 	return (char *)&buf[4];
448 }
449 EXPORT_SYMBOL(iscsi_parse_pr_out_transport_id);
450