Calculating a SHA hash with a string + secret key in python

Question

Amazon Product API now requires a signature with every request which I\'m trying to generate ushing Python.

The step I get hung up on is this one:

\"Calculat

Answer 1

>>> import hmac
>>> import hashlib
>>> import base64
>>> s = """GET
... webservices.amazon.com
... /onca/xml
... AWSAccessKeyId=00000000000000000000&ItemId=0679722769&Operation=ItemLookup&ResponseGroup=ItemAttributes%2COffers%2CImages%2CReviews&Service=AWSECommerceService&Timestamp=2009-01-01T12%3A00%3A00Z&Version=2009-01-06"""
>>> base64.b64encode(hmac.new("1234567890", msg=s, digestmod=hashlib.sha256).digest())
'Nace+U3Az4OhN7tISqgs1vdLBHBEijWcBeCqL5xN9xg='

Answer 2

import hmac
import hashlib
import base64
dig = hmac.new(b'1234567890', msg=your_bytes_string, digestmod=hashlib.sha256).digest()
base64.b64encode(dig).decode()      # py3k-mode
'Nace+U3Az4OhN7tISqgs1vdLBHBEijWcBeCqL5xN9xg='

Answer 3

From http://docs.python.org/library/hashlib.html#module-hashlib (modified a bit):

import hashlib
secretKey = "1234567890"
m = hashlib.sha256()

# Get string and put into givenString.

m.update(givenString + secretKey)
m.digest()

Answer 4

import hmac
import hashlib
import base64

digest = hmac.new(secret, msg=thing_to_hash, digestmod=hashlib.sha256).digest()
signature = base64.b64encode(digest).decode()

I know this sounds silly, but make sure you don't have a trailing space on your secret by accident.

Answer 5

If you are trying to sign up a user to AWS cognito using Python3, you can use the following code.

#For the SecretHash 
import hmac
import hashlib
import base64   

//Please note that the b in the secretKey and encode('utf-8') are really really important. 
secretKey = b"secret key that you get from Coginito -> User Pool -> General Settings -> App Clients-->Click on Show more details -> App client secret  "
 clientId = "Coginito -> User Pool -> General Settings -> App Clients-->App client id"
 digest = hmac.new(secretKey,
              msg=(user_name + clientId).encode('utf-8'),
              digestmod=hashlib.sha256
             ).digest()
 secrethash = base64.b64encode(digest).decode()

The username user_name in the above is same as the user that you want to register in the cognito

client = boto3.client('cognito-idp', region_name='eu-west-1' )

response = client.sign_up(
                    ClientId='Coginito -> User Pool -> General Settings -> App Clients-->App client id',
                    Username='Username of the person you are planning to register',
                    Password='Password of the person you are planning to register',
                    SecretHash=secrethash,
                    UserAttributes=[
                        {
                            'Name': 'given_name',
                            'Value': given_name
                        },
                        {
                            'Name': 'family_name',
                            'Value': family_name
                        },
                        {
                            'Name': 'email',
                            'Value': user_email
                        }
                    ],
                    ValidationData=[
                        {
                            'Name': 'email',
                            'Value': user_email
                        },
                    ]