MD5 hash in Python

Cryptographic hashes are used in day-day life like in digital signatures, message authentication codes, manipulation detection, fingerprints, checksums (message integrity check), hash tables, password storage and much more. They are also used in sending messages over network for security or storing messages in databases. 
There are many hash functions defined in the “hashlib” library in python. This article deals with explanation and working of MD5 hash.

MD5 Hash

This hash function accepts sequence of bytes and returns 128 bit hash value, usually used to check data integrity but has security issues. Functions associated : 

• encode() : Converts the string into bytes to be acceptable by hash function.
• digest() : Returns the encoded data in byte format.
• hexdigest() : Returns the encoded data in hexadecimal format.

Note:
The md5 library was a Python library that provided a simple interface for generating MD5 hashes. 
This library has been deprecated in favor of the hashlib library, which provides a more flexible and secure interface for generating hashes.

The below code demonstrates the working of MD5 hash accepting bytes and output as bytes. 

Python3

# Python 3 code to demonstrate the
# working of MD5 (byte - byte)

import hashlib

# encoding GeeksforGeeks using md5 hash
# function
result = hashlib.md5(b'GeeksforGeeks')

# printing the equivalent byte value.
print("The byte equivalent of hash is : ", end ="")
print(result.digest())

Output:

The byte equivalent of hash is : b'\xf1\xe0ix~\xcetS\x1d\x11%Y\x94\\hq'

Explanation : The above code takes byte and can be accepted by the hash function. The md5 hash function encodes it and then using digest(), byte equivalent encoded string is printed. 
Below code demonstrated how to take string as input and output hexadecimal equivalent of the encoded value. 

Python3

# Python 3 code to demonstrate the
# working of MD5 (string - hexadecimal)

import hashlib

# initializing string
str2hash = "GeeksforGeeks"

# encoding GeeksforGeeks using encode()
# then sending to md5()
result = hashlib.md5(str2hash.encode())

# printing the equivalent hexadecimal value.
print("The hexadecimal equivalent of hash is : ", end ="")
print(result.hexdigest())

Output:

The hexadecimal equivalent of hash is : f1e069787ece74531d112559945c6871

Explanation : The above code takes string and converts it into the byte equivalent using encode() so that it can be accepted by the hash function. The md5 hash function encodes it and then using hexdigest(), hexadecimal equivalent encoded string is printed.