bluetooth_name_parse.py

from base64 import urlsafe_b64decode
from base64 import urlsafe_b64encode
from bitstring import BitArray


#s = 'IzdJOVL8n14AAAAAAAAAIyKp4M61YgF3ZRkxBoJ60L_ZEVRlbGVmb25lIGRlIERpb2dv'
#s = 'IzdJOVL8n14AAAAAAAAAIyLe0ocONEH3GtJSL-NuRXJZEVRlbGVmb25lIGRlIERpb2dv'
#s = 'IzlRSkT8n14AAAAAAAAAFwLgZfG9UTrDaojDIMFJjCtcBU1pIEEx'
s = 'IzlRSkT8n14AAAAAAAAAFwLikXM7S-M1GDWPisM-4C5XBU1pIEEx'
#s = 'I0xWT1n8n14AAAAAAAAAFwKcYlprqvQFkU-aSqQ7R4dwBU1pIEEx'

# Using base64.urlsafe_b64decode() method
gfg = urlsafe_b64decode(s)
count = 0
namelength = 0
devicename = ""
endpointID = ""
serviceID = b''
print('\n', 'Base64 decoded byte array: ',gfg, '\n')

bytestr = bytearray(gfg)

for i, bite in enumerate(bytestr):
    #version and mode
    if (i == 0):
        lowfive = bite & 0b00011111
        highthree = bite >> 5

        #Mode: 5 least significant bits
        if lowfive == 0:
            print ("Unknown Mode")
        elif lowfive == 1:
            print ("Cluster Mode")
        elif lowfive == 2:
            print ("Star Mode")
        elif lowfive == 3:
            print ("P2P Mode")

        #Version: 3 most significant bits          
        print("Version", ":",f'{highthree:03b}')
    

    #Endpoint (supposed to be a string)
    if (i == 1):
        print ("Endpoint ID:", end = " ")
    if (i >=1 and i <= 4):
        endpointID+= chr(bite)
        if (i==4):
            print (endpointID, end = " ")


    #Service ID hash
    if (i == 5):
        print()
        print ("Service ID Hash:", end = " ")
    if (i >=5 and i <= 7):
        print (bite, end = " ")
        serviceID+= bite.to_bytes(1, 'little')
        if (i == 7):
            pass
            #showing service in hex
            #print ("{:08b}".format(int(serviceID.hex(),16)), end = " ")



    if (i == 8):
        print()
        print ("WebRTC State:", bite ,end = " ")

    #Reserved bytes, useless per google's code, but shown anyway
    if (i == 9):
        print()
        print ("Reserved:", end = " ")
    if (i >=9 and i <= 14):
        print (bite, end = " ")

    #endpoint info length
    if (i == 15):
        print()
        print ("Endpoint info length:", bite)
 
    #Device name length, byte 34
    if (i == 33):
        namelength = bite
        print ("Device name length: ", namelength)

    if (i > 33 and 33 + namelength >= i):
        character = chr(bite)
        devicename+= character
        if (33 + namelength == i):
            print ("Device name: ", devicename)


    if (i > 15 and i < 33):
        if (i == 16):
            print ("Unknown Bytes:")
        count = count + 1
        print(i, ": ", "{:08b}".format(bite) )
    

 #TODO bytes after length (defined in byte 15) are for UWB (ultra wide band), not relevant for current implementation