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ericwb wants to merge 1 commit into from
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Update hmac_timing_attack.py #4

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6 changes: 5 additions & 1 deletion python/stdlib/hmac_timing_attack.py
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Original file line number Diff line number Diff line change
@@ -1,3 +1,6 @@
# This example demostrates an insecure way of comparing a digest
# that exposes the code to a timing attack. This is because using
# equals operator on digest does not compare in constant time.
import hmac


Expand All @@ -8,6 +11,7 @@

key = b"my-secret-key"
password = b"pass"
digest = hmac.digest(key, password, digest="sha224")

Check warning on line 14 in python/stdlib/hmac_timing_attack.py

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Precaution / Precaution Unsubscribed

PY034: Inadequate Encryption Strength 

The given key is only '13' bytes which is insufficient for the
'sha224' algorithm.

return digest == received_digest
if digest == received_digest:

Check failure on line 16 in python/stdlib/hmac_timing_attack.py

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PY005: Observable Timing Discrepancy 

Comparing digests with the '==' operator is vulnerable to timing
attacks.
print("Authentication okay")
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