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Secure Password Hashing

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The PBKDF2 algorithm exposed by hashlib module can be used to perform secure password hashing. While this algorithm cannot prevent brute-force attacks in order to recover the original password from the stored hash, it makes such attacks very expensive. 

import hashlib
import os

salt = os.urandom(16)
hash = hashlib.pbkdf2_hmac('sha256', b'password', salt, 100000)

PBKDF2 can work with any digest algorithm, the above example uses SHA256 which is usually recommended. The random salt should be stored along with the hashed password, you will need it again in order to compare an entered password to the stored hash. It is essential that each password is hashed with a different salt. As to the number of rounds, it is recommended to set it as high as possible for your application.

If you want the result in hexadecimal, you can use the binascii module: 

import binascii
hexhash = binascii.hexlify(hash)

Note: While PBKDF2 isn’t bad, bcrypt and especially scrypt are considered stronger against brute-force attacks. Neither is part of the Python standard library at the moment.

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Security and Cryptograhy:
* Security and Cryptography
* Secure Password Hashing
* Calculating a Message Digest
* Available Hashing Algorithms
* File Hashing
* Symmetric encryption using pycrypto
* Generating RSA signatures using pycrypto
* Asymmetric RSA encryption using pycrypto
Table Of Contents
0 Getting Started
1 List comprehension
2 Filter
3 List
4 Functions
5 Decorators
6 Math module
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39 Incompatibilities moving from Python 2 to Python 3
40 Virtual environments
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68 pip PyPI Package Manager
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79 PyInstaller - Distributing Python Code
80 Iterables and Iterators
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83 args and kwargs
84 functools module
85 Garbage Collection
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87 Security and Cryptograhy
88 Pickle data serialization
89 urllib
90 Binary Data
91 Python and Excel
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98 PostgreSQL
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116 List destructuring
117 Accessing Python source code and bytecode
118 Mixins
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122 Plugin and Extension Classes
123 Websockets
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128 Polymorphism
129 Alternative Python implementations
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131 Web Server Gateway Intrerface WSGI
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135 Unicode
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138 Neo4j
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154 Audio
155 pyglet
156 queue module
157 ijson
158 webbrowser module
159 base64 module
160 Flask
161 Groupby
162 Sockets and Message Encryption / Decryption
163 pygame
164 Input Subset and Output External Data Files using Pandas
165 hashlib
166 Gzip
167 ctypes
168 Creating a Windows Service
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170 configparser
171 Common Exceptions
172 Optical Character Recognition OCR
173 Python Data Types
174 Partial functions
175 Generating graphs
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177 Functional Programming
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179 sys module
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181 virtualenvwrapper on Windows
182 Python Requests Post
183 Plotting with Matplotlib
184 Python Lex-Yacc
185 pyaudio
186 shelve
187 pip and PyPI Package Manager
188 Writing to CSV from String or List
189 Raise Custom Errors Exceptions
190 Using loops within functions
191 Contributors