This file is indexed.

/usr/share/cluster/fence_scsi_check is in fence-agents 4.0.22-2.

This file is owned by root:root, with mode 0o755.

The actual contents of the file can be viewed below.

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
#!/usr/bin/python -tt

import sys
import stat
import re
import os
import time
import logging
import atexit
import hashlib
import ctypes
sys.path.append("/usr/share/fence")
from fencing import fail_usage, run_command, atexit_handler, check_input, process_input, show_docs, fence_action, all_opt
from fencing import run_delay

#BEGIN_VERSION_GENERATION
RELEASE_VERSION="4.0.22"
BUILD_DATE="(built Sat, 06 Feb 2016 12:34:18 +0100)"
REDHAT_COPYRIGHT="Copyright (C) Red Hat, Inc. 2004-2010 All rights reserved."
#END_VERSION_GENERATION

STORE_PATH = "/var/run/cluster/fence_scsi"


def get_status(conn, options):
	del conn
	status = "off"
	for dev in options["devices"]:
		is_block_device(dev)
		reset_dev(options, dev)
		if options["--key"] in get_registration_keys(options, dev):
			status = "on"
		else:
			logging.debug("No registration for key "\
				+ options["--key"] + " on device " + dev + "\n")
			if options["--action"] == "on":
				status = "off"
				break
	return status


def set_status(conn, options):
	del conn
	count = 0
	if options["--action"] == "on":
		set_key(options)
		for dev in options["devices"]:
			is_block_device(dev)

			register_dev(options, dev)
			if options["--key"] not in get_registration_keys(options, dev):
				count += 1
				logging.debug("Failed to register key "\
					+ options["--key"] + "on device " + dev + "\n")
				continue
			dev_write(dev, options)

			if get_reservation_key(options, dev) is None \
			and not reserve_dev(options, dev) \
			and get_reservation_key(options, dev) is None:
				count += 1
				logging.debug("Failed to create reservation (key="\
					+ options["--key"] + ", device=" + dev + ")\n")

	else:
		host_key = get_key()
		if host_key == options["--key"].lower():
			fail_usage("Failed: keys cannot be same. You can not fence yourself.")
		for dev in options["devices"]:
			is_block_device(dev)

			if options["--key"] in get_registration_keys(options, dev):
				preempt_abort(options, host_key, dev)

		for dev in options["devices"]:
			if options["--key"] in get_registration_keys(options, dev):
				count += 1
				logging.debug("Failed to remove key "\
					+ options["--key"] + " on device " + dev + "\n")
				continue

			if not get_reservation_key(options, dev):
				count += 1
				logging.debug("No reservation exists on device " + dev + "\n")
	if count:
		logging.error("Failed to verify " + str(count) + " device(s)")
		sys.exit(1)


# check if host is ready to execute actions
def do_action_monitor(options):
	# Check if required binaries are installed
	if bool(run_cmd(options, options["--sg_persist-path"] + " -V")["err"]):
		logging.error("Unable to run " + options["--sg_persist-path"])
		return 1
	elif bool(run_cmd(options, options["--sg_turs-path"] + " -V")["err"]):
		logging.error("Unable to run " + options["--sg_turs-path"])
		return 1
	elif ("--devices" not in options and 
			bool(run_cmd(options,	options["--vgs-path"] + " --version")["err"])):
		logging.error("Unable to run " + options["--vgs-path"])
		return 1

	# Keys have to be present in order to fence/unfence
	get_key()
	dev_read()

	return 0


#run command, returns dict, ret["err"] = exit code; ret["out"] = output
def run_cmd(options, cmd):
	ret = {}
	(ret["err"], ret["out"], _) = run_command(options, cmd)
	ret["out"] = "".join([i for i in ret["out"] if i is not None])
	return ret


# check if device exist and is block device
def is_block_device(dev):
	if not os.path.exists(dev):
		fail_usage("Failed: device \"" + dev + "\" does not exist")
	if not stat.S_ISBLK(os.stat(dev).st_mode):
		fail_usage("Failed: device \"" + dev + "\" is not a block device")


# cancel registration
def preempt_abort(options, host, dev):
	reset_dev(options,dev)
	cmd = options["--sg_persist-path"] + " -n -o -A -T 5 -K " + host + " -S " + options["--key"] + " -d " + dev
	return not bool(run_cmd(options, cmd)["err"])


def reset_dev(options, dev):
	return run_cmd(options, options["--sg_turs-path"] + " " + dev)["err"]


def register_dev(options, dev):
	dev = os.path.realpath(dev)
	if re.search(r"^dm", dev[5:]):
		for slave in get_mpath_slaves(dev):
			register_dev(options, slave)
		return True
	reset_dev(options, dev)
	cmd = options["--sg_persist-path"] + " -n -o -I -S " + options["--key"] + " -d " + dev
	cmd += " -Z" if "--aptpl" in options else ""
	#cmd return code != 0 but registration can be successful
	return not bool(run_cmd(options, cmd)["err"])


def reserve_dev(options, dev):
	reset_dev(options,dev)
	cmd = options["--sg_persist-path"] + " -n -o -R -T 5 -K " + options["--key"] + " -d " + dev
	return not bool(run_cmd(options, cmd)["err"])


def get_reservation_key(options, dev):
	reset_dev(options,dev)
	cmd = options["--sg_persist-path"] + " -n -i -r -d " + dev
	out = run_cmd(options, cmd)
	if out["err"]:
		fail_usage("Cannot get reservation key")
	match = re.search(r"\s+key=0x(\S+)\s+", out["out"], re.IGNORECASE)
	return match.group(1) if match else None


def get_registration_keys(options, dev):
	reset_dev(options,dev)
	keys = []
	cmd = options["--sg_persist-path"] + " -n -i -k -d " + dev
	out = run_cmd(options, cmd)
	if out["err"]:
		fail_usage("Cannot get registration keys")
	for line in out["out"].split("\n"):
		match = re.search(r"\s+0x(\S+)\s*", line)
		if match:
			keys.append(match.group(1))
	return keys


def get_cluster_id(options):
	cmd = options["--corosync-cmap-path"] + " totem.cluster_name"

	match = re.search(r"\(str\) = (\S+)\n", run_cmd(options, cmd)["out"])
	return hashlib.md5(match.group(1)).hexdigest() if match else fail_usage("Failed: cannot get cluster name")


def get_node_id(options):
	cmd = options["--corosync-cmap-path"] + " nodelist."

	match = re.search(r".(\d).ring._addr \(str\) = " + options["--nodename"] + "\n", run_cmd(options, cmd)["out"])
	return match.group(1) if match else fail_usage("Failed: unable to parse output of corosync-cmapctl or node does not exist")


def generate_key(options):
	return "%.4s%.4d" % (get_cluster_id(options), int(get_node_id(options)))


# save node key to file
def set_key(options):
	file_path = options["store_path"] + ".key"
	if not os.path.isdir(os.path.dirname(options["store_path"])):
		os.makedirs(os.path.dirname(options["store_path"]))
	try:
		f = open(file_path, "w")
	except IOError:
		fail_usage("Failed: Cannot open file \""+ file_path + "\"")
	f.write(options["--key"].lower() + "\n")
	f.close()


# read node key from file
def get_key(fail=True):
	file_path = STORE_PATH + ".key"
	try:
		f = open(file_path, "r")
	except IOError:
		if fail:
			fail_usage("Failed: Cannot open file \""+ file_path + "\"")
		else:
			return None
	return f.readline().strip().lower()


def dev_write(dev, options):
	file_path = options["store_path"] + ".dev"
	if not os.path.isdir(os.path.dirname(options["store_path"])):
		os.makedirs(os.path.dirname(options["store_path"]))
	try:
		f = open(file_path, "a+")
	except IOError:
		fail_usage("Failed: Cannot open file \""+ file_path + "\"")
	out = f.read()
	if not re.search(r"^" + dev + "\s+", out):
		f.write(dev + "\n")
	f.close()


def dev_read(fail=True):
	file_path = STORE_PATH + ".dev"
	try:
		f = open(file_path, "r")
	except IOError:
		if fail:
			fail_usage("Failed: Cannot open file \"" + file_path + "\"")
		else:
			return None
	# get not empty lines from file
	devs = [line.strip() for line in f if line.strip()]
	f.close()
	return devs


def dev_delete(options):
	file_path = options["store_path"] + ".dev"
	os.remove(file_path) if os.path.exists(file_path) else None


def get_clvm_devices(options):
	devs = []
	cmd = options["--vgs-path"] + " " +\
	"--noheadings " +\
	"--separator : " +\
	"--sort pv_uuid " +\
	"--options vg_attr,pv_name "+\
	"--config 'global { locking_type = 0 } devices { preferred_names = [ \"^/dev/dm\" ] }'"
	out = run_cmd(options, cmd)
	if out["err"]:
		fail_usage("Failed: Cannot get clvm devices")
	for line in out["out"].split("\n"):
		if 'c' in line.split(":")[0]:
			devs.append(line.split(":")[1])
	return devs


def get_mpath_slaves(dev):
	if dev[:5] == "/dev/":
		dev = dev[5:]
	slaves = [i for i in os.listdir("/sys/block/" + dev + "/slaves/") if i[:1] != "."]
	if slaves[0][:2] == "dm":
		slaves = get_mpath_slaves(slaves[0])
	else:
		slaves = ["/dev/" + x for x in slaves]
	return slaves


def define_new_opts():
	all_opt["devices"] = {
		"getopt" : "d:",
		"longopt" : "devices",
		"help" : "-d, --devices=[devices]        List of devices to use for current operation",
		"required" : "0",
		"shortdesc" : "List of devices to use for current operation. Devices can \
be comma-separated list of raw device (eg. /dev/sdc) or device-mapper multipath \
devices (eg. /dev/dm-3). Each device must support SCSI-3 persistent reservations.",
		"order": 1
	}
	all_opt["nodename"] = {
		"getopt" : "n:",
		"longopt" : "nodename",
		"help" : "-n, --nodename=[nodename]      Name of the node to be fenced",
		"required" : "0",
		"shortdesc" : "Name of the node to be fenced. The node name is used to \
generate the key value used for the current operation. This option will be \
ignored when used with the -k option.",
		"order": 1
	}
	all_opt["key"] = {
		"getopt" : "k:",
		"longopt" : "key",
		"help" : "-k, --key=[key]                Key to use for the current operation",
		"required" : "0",
		"shortdesc" : "Key to use for the current operation. This key should be \
unique to a node. For the \"on\" action, the key specifies the key use to \
register the local node. For the \"off\" action, this key specifies the key to \
be removed from the device(s).",
		"order": 1
	}
	all_opt["aptpl"] = {
		"getopt" : "a",
		"longopt" : "aptpl",
		"help" : "-a, --aptpl                    Use the APTPL flag for registrations",
		"required" : "0",
		"shortdesc" : "Use the APTPL flag for registrations. This option is only used for the 'on' action.",
		"order": 1
	}
	all_opt["logfile"] = {
		"getopt" : ":",
		"longopt" : "logfile",
		"help" : "-f, --logfile                  Log output (stdout and stderr) to file",
		"required" : "0",
		"shortdesc" : "Log output (stdout and stderr) to file",
		"order": 5
	}
	all_opt["corosync-cmap_path"] = {
		"getopt" : ":",
		"longopt" : "corosync-cmap-path",
		"help" : "--corosync-cmap-path=[path]    Path to corosync-cmapctl binary",
		"required" : "0",
		"shortdesc" : "Path to corosync-cmapctl binary",
		"default" : "/usr/sbin/corosync-cmapctl",
		"order": 300
	}
	all_opt["sg_persist_path"] = {
		"getopt" : ":",
		"longopt" : "sg_persist-path",
		"help" : "--sg_persist-path=[path]       Path to sg_persist binary",
		"required" : "0",
		"shortdesc" : "Path to sg_persist binary",
		"default" : "/usr/bin/sg_persist",
		"order": 300
	}
	all_opt["sg_turs_path"] = {
		"getopt" : ":",
		"longopt" : "sg_turs-path",
		"help" : "--sg_turs-path=[path]          Path to sg_turs binary",
		"required" : "0",
		"shortdesc" : "Path to sg_turs binary",
		"default" : "/usr/bin/sg_turs",
		"order": 300
	}
	all_opt["vgs_path"] = {
		"getopt" : ":",
		"longopt" : "vgs-path",
		"help" : "--vgs-path=[path]              Path to vgs binary",
		"required" : "0",
		"shortdesc" : "Path to vgs binary",
		"default" : "/sbin/vgs",
		"order": 300
	}


def scsi_check_get_verbose():
	try:
		f = open("/etc/sysconfig/watchdog", "r")
	except IOError:
		return False
	match = re.search(r"^\s*verbose=yes", "".join(f.readlines()), re.MULTILINE)
	f.close()
	return bool(match)


def scsi_check(hardreboot=False):
	if len(sys.argv) >= 3 and sys.argv[1] == "repair":
		return int(sys.argv[2])
	options = {}
	options["--sg_turs-path"] = "/usr/bin/sg_turs"
	options["--sg_persist-path"] = "/usr/bin/sg_persist"
	options["--power-timeout"] = "5"
	if scsi_check_get_verbose():
		logging.getLogger().setLevel(logging.DEBUG)
	devs = dev_read(fail=False)
	if not devs:
		logging.error("No devices found")
		return 0
	key = get_key(fail=False)
	if not key:
		logging.error("Key not found")
		return 0
	for dev in devs:
		if key in get_registration_keys(options, dev):
			logging.debug("key " + key + " registered with device " + dev)
			return 0
		else:
			logging.debug("key " + key + " not registered with device " + dev)
	logging.debug("key " + key + " registered with any devices")

	if hardreboot == True:
		libc = ctypes.cdll['libc.so.6']
		libc.reboot(0x1234567)
	return 2


def main():

	atexit.register(atexit_handler)

	device_opt = ["no_login", "no_password", "devices", "nodename", "key",\
	"aptpl", "fabric_fencing", "on_target", "corosync-cmap_path",\
	"sg_persist_path", "sg_turs_path", "logfile", "vgs_path", "force_on"]

	define_new_opts()

	all_opt["delay"]["getopt"] = "H:"

	#fence_scsi_check
	if os.path.basename(sys.argv[0]) == "fence_scsi_check":
		sys.exit(scsi_check())
	elif os.path.basename(sys.argv[0]) == "fence_scsi_check_hardreboot":
		sys.exit(scsi_check(True))

	options = check_input(device_opt, process_input(device_opt), other_conditions=True)

	docs = {}
	docs["shortdesc"] = "Fence agent for SCSI persistentl reservation"
	docs["longdesc"] = "fence_scsi is an I/O fencing agent that uses SCSI-3 \
persistent reservations to control access to shared storage devices. These \
devices must support SCSI-3 persistent reservations (SPC-3 or greater) as \
well as the \"preempt-and-abort\" subcommand.\nThe fence_scsi agent works by \
having each node in the cluster register a unique key with the SCSI \
devive(s). Once registered, a single node will become the reservation holder \
by creating a \"write exclusive, registrants only\" reservation on the \
device(s). The result is that only registered nodes may write to the \
device(s). When a node failure occurs, the fence_scsi agent will remove the \
key belonging to the failed node from the device(s). The failed node will no \
longer be able to write to the device(s). A manual reboot is required."
	docs["vendorurl"] = ""
	show_docs(options, docs)

	run_delay(options)

	# backward compatibility layer BEGIN
	if "--logfile" in options:
		try:
			logfile = open(options["--logfile"], 'w')
			sys.stderr = logfile
			sys.stdout = logfile
		except IOError:
			fail_usage("Failed: Unable to create file " + options["--logfile"])
	# backward compatibility layer END

	options["store_path"] = STORE_PATH

	# Input control BEGIN
	stop_after_error = False if options["--action"] == "validate-all" else True

	if options["--action"] == "monitor":
		sys.exit(do_action_monitor(options))

	if not (("--nodename" in options and options["--nodename"])\
	or ("--key" in options and options["--key"])):
		fail_usage("Failed: nodename or key is required", stop_after_error)

	if not ("--key" in options and options["--key"]):
		options["--key"] = generate_key(options)

	if options["--key"] == "0" or not options["--key"]:
		fail_usage("Failed: key cannot be 0", stop_after_error)

	if options["--action"] == "validate-all":
		sys.exit(0)

	options["--key"] = options["--key"].lstrip('0')

	if not ("--devices" in options and options["--devices"].split(",")):
		options["devices"] = get_clvm_devices(options)
	else:
		options["devices"] = options["--devices"].split(",")

	if not options["devices"]:
		fail_usage("Failed: No devices found")
	# Input control END

	result = fence_action(None, options, set_status, get_status)
	sys.exit(result)

if __name__ == "__main__":
	main()