33 lines
751 B
Plaintext
33 lines
751 B
Plaintext
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== How to fix it in Cryptodome
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=== Code examples
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The example uses a hardcoded IV as a nonce, which causes AES-CCM to be insecure. To fix it, a nonce is randomly generated instead.
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==== Noncompliant code example
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[source,python,diff-id=101,diff-type=noncompliant]
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----
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from Crypto.Cipher import AES
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def encrypt(key, plaintext):
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nonce = '7cVgr5cbdCZV'.encode('utf-8')
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cipher = AES.new(key, AES.MODE_CCM, nonce)
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cipher.encrypt(plaintext) # Noncompliant
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----
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==== Compliant solution
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[source,python,diff-id=101,diff-type=compliant]
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----
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from Crypto.Cipher import AES
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def encrypt(key, plaintext):
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cipher = AES.new(key, AES.MODE_CCM)
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cipher.encrypt_and_digest(plaintext)
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----
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include::../../common/how-does-this-work.adoc[]
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