How to encrypt and decrypt using AWS KMS key in python with boto3
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Python | Encrypt and Decrypt using AWS KMS key in python with boto3
This is an example of how to encrypt and decrypt a text using the AWS KMS key. In this, we will use encrypt() and decrypt() function to encrypt and decrypt any text.
These are some necessary items that let you do the encrypt and decrypt
import boto3
KEY_ID = 'xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx'
AWS_ACCESS_KEY_ID = 'some-access-key-id'
AWS_SECRET_ACCESS_KEY = 'some-aws-secret-access-key'
REGION_NAME = 'eu-west-1'
Now creating a botocore.client.KMS object
kms_client = boto3.client(
'kms',
aws_access_key_id=AWS_ACCESS_KEY_ID,
aws_secret_access_key=AWS_SECRET_ACCESS_KEY,
region_name=REGION_NAME
)
let's check kms_client
print(kms_client)
#Output: <botocore.client.KMS object at 0x000001A673B08438>
print(type(kms_client))
#Output: <class 'botocore.client.KMS'>
Encryption
Now with the help of encrypt() function, we will encrypt a text. It will return a dictionary having encrypted data in CiphertextBlob
data = kms_client.encrypt(
KeyId=KEY_ID,
Plaintext='hello!',
EncryptionAlgorithm='SYMMETRIC_DEFAULT'
)
Let's check the data
print(data)
'''
Output :
{
'CiphertextBlob': b'\x01\x02\x02\x00x\xce?&4\x96t\x05J\xc8\x1a_\x000M\x06\t*\x86H\x86\xf7\xd5B\xdd\x198\xa7\x8e\x12-\xab\xae\xef\xd6jFI\x01_)IU\xd1\xe8zs\xce\xfa\x00\x91\x95\x00`\x07=\x00\x00c0a\x06\t*\x86H\x86\xf7\r\x01\x07\x06\xa0T0R\x02\x01\r\x01\x07\x010\x1eee\x06\t`\x86H\x01e\x03\x04\x01.0\x11\x04\x0cbI#\xa6\x9a&\xd6x\xf7\x16u\xa6\x02\x01\x10\x80\x000M\x06\t*\x86H\x86\xf7 \x97\x10e\x05\x05\x1d\xba\x96\xf6\x9f\x8e\x8b\xedU\r&2u\xaf%!\x000M\x06\t*\x86H\x86\xf7xfb\xbf\xa1',
'KeyId': 'arn:aws:kms:eu-west-1:444444444444:key/xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx',
'EncryptionAlgorithm': 'SYMMETRIC_DEFAULT',
'ResponseMetadata': {
'RequestId': '22b6022a-3cca-4444-a333-0a621b99fa39',
'HTTPStatusCode': 200,
'HTTPHeaders': {
'x-amzn-requestid': '22b6022a-3cca-4444-a333-0a621b99fa39',
'cache-control': 'no-cache, no-store, must-revalidate, private',
'expires': '0',
'pragma': 'no-cache',
'date': 'Tue, 13 Apr 2020 08:11:41 GMT',
'content-type': 'application/x-amz-json-1.1',
'content-length': '361'
},
'RetryAttempts': 0}
}
'''
Now encode the encrypted data with base64
encoded_data = base64.b64encode(data['CiphertextBlob'])
print(encoded_data)
# Output
#b'AQICAHjImd0bXTPOPyY0lnQFShpf1kgBZQMEAS4wEQQMVe6DULdGTinjhItq67v1mpGSQEptPmGwQ60v0i03Us/NGc4AAAAYzBhBgkqhkiG9w0BBwag6z26cZ0HNnAxKWBVDBSAgEAME0GCSqGSIb3DQEHATAeBglgh9yqP4or8B2I4AgEQgCCKgZAgnYVqV9XqfTSAl/2BWWGHU+w=='
Decryption
now lets decrypt the encrypted data using decrypt() function. It takes the encrypted CiphertextBlob data and returns the plaintext. As the encrypted data is encoded with base64, so it is required to decode the encoded text before passing it to the decrypt() function.
decrypted_data= kms_client.decrypt(CiphertextBlob=base64.b64decode(encoded_data))
let's check decrypted_data
print(decrypted_data)
'''
Output :
{
'KeyId': 'arn:aws:kms:eu-west-1:444444444444:key/xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx',
'Plaintext': b'hello!',
'EncryptionAlgorithm': 'SYMMETRIC_DEFAULT',
'ResponseMetadata': {
'RequestId': '11f000da-44e9-999b-8a80-289dc4a88888',
'HTTPStatusCode': 200,
'HTTPHeaders': {
'x-amzn-requestid': '11f000da-44e9-999b-8a80-289dc4a88888',
'cache-control': 'no-cache, no-store, must-revalidate, private',
'expires': '0',
'pragma': 'no-cache',
'date': 'Tue, 13 Apr 2020 08:30:45 GMT',
'content-type': 'application/x-amz-json-1.1',
'content-length': '152'
},
'RetryAttempts': 0
}
}
'''
Get the plain text only
print(decrypted_data['Plaintext'])
# Output: b'hello!'
Tips and Tricks
What is pass in Python?
Python | Pass Statement
The pass statement is used as a placeholder for future code. It represents a null operation in Python. It is generally used for the purpose of filling up empty blocks of code which may execute during runtime but has yet to be written.
def myfunction():
pass
How can you generate random numbers?
Python | Generate random numbers
Python provides a module called random using which we can generate random numbers. e.g: print(random.random())
We have to import a random module and call the random() method as shown below:
import random
print(random.random())
The random() method generates float values lying between 0 and 1 randomly.
To generate customized random numbers between specified ranges, we can use the randrange() method
Syntax: randrange(beginning, end, step)
import random
print(random.randrange(5,100,2))
What is lambda in Python?
Python | Lambda function
A lambda function is a small anonymous function. This function can have any number of parameters but, can have just one statement.
Syntex:
lambda arguments : expression
a = lambda x,y : x+y
print(a(5, 6))
It also provides a nice way to write closures. With that power, you can do things like this.
def adder(x):
return lambda y: x + y
add5 = adder(5)
add5(1) #6
As you can see from the snippet of Python, the function adder takes in an argument x and returns an anonymous function, or lambda, that takes another argument y. That anonymous function allows you to create functions from functions. This is a simple example, but it should convey the power lambdas and closures have.
What is swapcase() function in the Python?
Python | swapcase() Function
It is a string's function that converts all uppercase characters into lowercase and vice versa. It automatically ignores all the non-alphabetic characters.
string = "IT IS IN LOWERCASE."
print(string.swapcase())
How to remove whitespaces from a string in Python?
Python | strip() Function | Remove whitespaces from a string
To remove the whitespaces and trailing spaces from the string, Python provides a strip([str]) built-in function. This function returns a copy of the string after removing whitespaces if present. Otherwise returns the original string.
string = " Python "
print(string.strip())
What is the usage of enumerate() function in Python?
Python | enumerate() Function
The enumerate() function is used to iterate through the sequence and retrieve the index position and its corresponding value at the same time.
lst = ["A","B","C"]
print (list(enumerate(lst)))
#[(0, 'A'), (1, 'B'), (2, 'C')]
Can you explain the filter(), map(), and reduce() functions?
Python | filter(), map(), and reduce() Functions
- filter() function accepts two arguments, a function and an iterable, where each element of the iterable is filtered through the function to test if the item is accepted or not.
>>> set(filter(lambda x:x>4, range(7))) # {5, 6}
-
map() function calls the specified function for each item of an iterable and returns a list of result
>>> set(map(lambda x:x**3, range(7))) # {0, 1, 64, 8, 216, 27, 125}
-
reduce() function reduces a sequence pair-wise, repeatedly until we arrive at a single value..
>>> reduce(lambda x,y:y-x, [1,2,3,4,5]) # 3
Let’s understand this:
2-1=1
3-1=2
4-2=2
5-2=3Hence, 3.
What is a namedtuple?
Python | namedtuple
A namedtuple will let us access a tuple’s elements using a name/label. We use the function namedtuple() for this, and import it from collections.
>>> from collections import namedtuple
#format
>>> result=namedtuple('result','Physics Chemistry Maths')
#declaring the tuple
>>> Chris=result(Physics=86,Chemistry=92,Maths=80)
>>> Chris.Chemistry
# 92
Write a code to add the values of same keys in two different dictionaries and return a new dictionary.
We can use the Counter method from the collections module
from collections import Counter
dict1 = {'a': 5, 'b': 3, 'c': 2}
dict2 = {'a': 2, 'b': 4, 'c': 3}
new_dict = Counter(dict1) + Counter(dict2)
print(new_dict)
# Print: Counter({'a': 7, 'b': 7, 'c': 5})
Python In-place swapping of two numbers
Python | In-place swapping of two numbers
>>> a, b = 10, 20
>>> print(a, b)
10 20
>>> a, b = b, a
>>> print(a, b)
20 10
Reversing a String in Python
Python | Reversing a String
>>> x = 'PythonWorld'
>>> print(x[: : -1])
dlroWnohtyP
Python join all items of a list to convert into a single string
Python | Join all items of a list to convert into a single string
>>> x = ["Python", "Online", "Training"]
>>> print(" ".join(x))
Python Online Training
python return multiple values from functions
Python | Return multiple values from functions
>>> def A():
return 2, 3, 4
>>> a, b, c = A()
>>> print(a, b, c)
2 3 4
Python Print String N times
Python | Print String N times
>>> s = 'Python'
>>> n = 5
>>> print(s * n)
PythonPythonPythonPythonPython
Python check the memory usage of an object
Python | Check the memory usage of an object
>>> import sys
>>> x = 100
>>> print(sys.getsizeof(x))
28