1#!/usr/bin/env python3 2# SPDX-License-Identifier: BSD-3-Clause 3# Copyright (C) 2021 Intel Corporation 4# All rights reserved. 5# 6 7import argparse 8import os 9import stat 10import struct 11 12 13def block_exists(block): 14 return os.path.exists(block) and stat.S_ISBLK(os.stat(block).st_mode) 15 16 17def lbsize(block): 18 if not os.path.exists("/sys/block/%s/queue/logical_block_size" % block): 19 return 512 20 21 with open("/sys/block/%s/queue/logical_block_size" % block) as lbs: 22 return int(lbs.read()) 23 24 25def readb(block, offset, length, format="Q"): 26 b = os.open(block, os.O_RDONLY) 27 os.lseek(b, offset, os.SEEK_SET) 28 data = os.read(b, length) 29 os.close(b) 30 return struct.unpack(format, data)[0] 31 32 33def is_spdk_gpt(block, entry): 34 block_path = "/dev/" + block 35 36 if not block_exists(block_path): 37 print("%s is not a block device" % block) 38 return False 39 40 disk_lbsize = lbsize(block) 41 gpt_sig = 0x5452415020494645 # EFI PART 42 spdk_guid = [0x7c5222bd, 0x8f5d, 0x4087, 0x9c00, 0xbf9843c7b58c] 43 44 if readb(block_path, disk_lbsize, 8) != gpt_sig: 45 print("No valid GPT data, bailing") 46 return False 47 48 part_entry_lba = disk_lbsize * readb(block_path, disk_lbsize + 72, 8) 49 part_entry_lba = part_entry_lba + (entry - 1) * 128 50 51 guid = [ 52 readb(block_path, part_entry_lba, 4, "I"), 53 readb(block_path, part_entry_lba + 4, 2, "H"), 54 readb(block_path, part_entry_lba + 6, 2, "H"), 55 readb(block_path, part_entry_lba + 8, 2, ">H"), 56 readb(block_path, part_entry_lba + 10, 8, ">Q") >> 16 57 ] 58 59 return guid == spdk_guid 60 61 62if __name__ == "__main__": 63 parser = argparse.ArgumentParser(description='Checks if SPDK GUID is present on given block device') 64 parser.add_argument('block', type=str, help='block device to check') 65 parser.add_argument('-e', '--entry', dest='entry', help='GPT partition entry', 66 required=False, type=int, default=1) 67 args = parser.parse_args() 68 try: 69 if is_spdk_gpt(args.block.replace("/dev/", ""), args.entry): 70 exit(0) 71 exit(1) 72 except Exception as e: 73 print("Failed to read GPT data from %s (%s)" % (args.block, e)) 74 exit(1) 75