-
-
Save masterashu/f90b8ba6d4324d0a7d65ab0f2d8306c0 to your computer and use it in GitHub Desktop.
import base64 | |
import string | |
import random | |
import hashlib | |
from Crypto.Cipher import AES | |
IV = "@@@@&&&&####$$$$" | |
BLOCK_SIZE = 16 | |
def generate_checksum(param_dict, merchant_key, salt=None): | |
params_string = __get_param_string__(param_dict) | |
salt = salt if salt else __id_generator__(4) | |
final_string = '%s|%s' % (params_string, salt) | |
hasher = hashlib.sha256(final_string.encode()) | |
hash_string = hasher.hexdigest() | |
hash_string += salt | |
return __encode__(hash_string, IV, merchant_key) | |
def generate_refund_checksum(param_dict, merchant_key, salt=None): | |
for i in param_dict: | |
if("|" in param_dict[i]): | |
param_dict = {} | |
exit() | |
params_string = __get_param_string__(param_dict) | |
salt = salt if salt else __id_generator__(4) | |
final_string = '%s|%s' % (params_string, salt) | |
hasher = hashlib.sha256(final_string.encode()) | |
hash_string = hasher.hexdigest() | |
hash_string += salt | |
return __encode__(hash_string, IV, merchant_key) | |
def generate_checksum_by_str(param_str, merchant_key, salt=None): | |
params_string = param_str | |
salt = salt if salt else __id_generator__(4) | |
final_string = '%s|%s' % (params_string, salt) | |
hasher = hashlib.sha256(final_string.encode()) | |
hash_string = hasher.hexdigest() | |
hash_string += salt | |
return __encode__(hash_string, IV, merchant_key) | |
def verify_checksum(param_dict, merchant_key, checksum): | |
# Remove checksum | |
if 'CHECKSUMHASH' in param_dict: | |
param_dict.pop('CHECKSUMHASH') | |
# Get salt | |
paytm_hash = __decode__(checksum, IV, merchant_key) | |
salt = paytm_hash[-4:] | |
calculated_checksum = generate_checksum(param_dict, merchant_key, salt=salt) | |
return calculated_checksum == checksum | |
def verify_checksum_by_str(param_str, merchant_key, checksum): | |
# Remove checksum | |
#if 'CHECKSUMHASH' in param_dict: | |
#param_dict.pop('CHECKSUMHASH') | |
# Get salt | |
paytm_hash = __decode__(checksum, IV, merchant_key) | |
salt = paytm_hash[-4:] | |
calculated_checksum = generate_checksum_by_str(param_str, merchant_key, salt=salt) | |
return calculated_checksum == checksum | |
def __id_generator__(size=6, chars=string.ascii_uppercase + string.digits + string.ascii_lowercase): | |
return ''.join(random.choice(chars) for _ in range(size)) | |
def __get_param_string__(params): | |
params_string = [] | |
for key in sorted(params.keys()): | |
if "REFUND" in params[key] or "|" in params[key]: | |
respons_dict = {} | |
exit() | |
value = params[key] | |
params_string.append('' if value == 'null' else str(value)) | |
return '|'.join(params_string) | |
__pad__ = lambda s: s + (BLOCK_SIZE - len(s) % BLOCK_SIZE) * chr(BLOCK_SIZE - len(s) % BLOCK_SIZE) | |
__unpad__ = lambda s: s[0:-ord(s[-1])] | |
def __encode__(to_encode, iv, key): | |
# Pad | |
to_encode = __pad__(to_encode) | |
# Encrypt | |
c = AES.new(key.encode('utf-8'), AES.MODE_CBC, iv.encode('utf-8')) | |
to_encode = c.encrypt(to_encode.encode('utf-8')) | |
# Encode | |
to_encode = base64.b64encode(to_encode) | |
return to_encode.decode("UTF-8") | |
def __decode__(to_decode, iv, key): | |
# Decode | |
to_decode = base64.b64decode(to_decode) | |
# Decrypt | |
c = AES.new(key.encode('utf-8'), AES.MODE_CBC, iv.encode('utf-8')) | |
to_decode = c.decrypt(to_decode) | |
if type(to_decode) == bytes: | |
# convert bytes array to str. | |
to_decode = to_decode.decode() | |
# remove pad | |
return __unpad__(to_decode) | |
if __name__ == "__main__": | |
params = { | |
"MID": "mid", | |
"ORDER_ID": "order_id", | |
"CUST_ID": "cust_id", | |
"TXN_AMOUNT": "1", | |
"CHANNEL_ID": "WEB", | |
"INDUSTRY_TYPE_ID": "Retail", | |
"WEBSITE": "xxxxxxxxxxx" | |
} | |
print(verify_checksum( | |
params, 'xxxxxxxxxxxxxxxx', | |
"CD5ndX8VVjlzjWbbYoAtKQIlvtXPypQYOg0Fi2AUYKXZA5XSHiRF0FDj7vQu66S8MHx9NaDZ/uYm3WBOWHf+sDQAmTyxqUipA7i1nILlxrk=")) | |
# print(generate_checksum(params, "xxxxxxxxxxxxxxxx")) |
Make sure you have this file in the same folder. Replace PayTm with the file name(without extension) in the from PayTm import Checksum
. Note: python import are case sensitive.
Hey, I am a new user to PayTM Businesses, and it seems they have deprecated this API, and used a new one. Still I am trying to integrate it, Can you let me know if it will work. I am stuck on invalid checksum error when i send the data to staging
@mayankwadhwani Yes, Thanks for pointing that out. I will create a post/sample for the new one and mention it here.
I am getting error at Incorrect AES key length (23 bytes)....i am using windows7 32 bit 4 gb ram...
please help me i am absulute begginer.
ModuleNotFoundError: No module named 'PayTm'
I got the same error ,please help me out.
@masterashu
Bro i was asking because i wrote
from PayTm import Checksum in views.py
And then i got that error please help me in this way