"cryptography.hazmat.primitives.asymmetric.ec"

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∟"cryptography.hazmat.primitives.asymmetric.ec" - Generate EC Keys

This section provides a tutorial example on how to use 'cryptography.hazmat.primitives.asymmetric' module to generate EC private-public key pairs in Python scripts.

To generate EC private-public key pairs for production systems, you can use the cryptography.hazmat.primitives.asymmetric.ec module. Here is a Python example script that generates EC key pairs of a given curve name.

# cryptography-hazmat-ec-keys.py
# Copyright (c) 2025, HerongYang.com, All Rights Reserved.
#
import sys
if (len(sys.argv) < 2):
  print("Usage: python cryptography-hazmat-ec-keys.py 'list'|curve")
  exit()
cmd = sys.argv[1]

from cryptography.hazmat.primitives.asymmetric import ec
from cryptography.hazmat.primitives import serialization

if cmd=='list': 
  types = ec._CURVE_TYPES
  for key in types.keys():
    print(key.upper())
    # print(val)
else:
  curve = getattr(ec, cmd.upper())
  private_key = ec.generate_private_key(curve())
  public_key = private_key.public_key()
  print("Curve name: "+private_key.curve.__class__.__name__)
  print("Key size: "+str(private_key.key_size))
  print(f"x: {private_key.private_numbers().public_numbers.x}")
  print(f"y: {private_key.private_numbers().public_numbers.y}")
  print(f"d: {private_key.private_numbers().private_value}")
  print()
  print("Private key: \n"
    + str(private_key.private_bytes(
      serialization.Encoding.PEM,
      serialization.PrivateFormat.TraditionalOpenSSL,
      serialization.NoEncryption()      
    ), "utf-8")
  )
  print("Public key: \n"
    + str(public_key.public_bytes(
      serialization.Encoding.PEM,
      serialization.PublicFormat.SubjectPublicKeyInfo    
    ), "utf-8")
  )

List curves supported by the cryptography package

herong$ python3 cryptography-hazmat-ec-keys.py list 

PRIME192V1
PRIME256V1
SECP192R1
SECP224R1
SECP256R1
SECP384R1
SECP521R1
SECP256K1
BRAINPOOLP256R1
BRAINPOOLP384R1
BRAINPOOLP512R1

Generate private-public key pairs of a given curve

herong$ python3 cryptography-hazmat-ec-keys.py SECP256R1 

Curve name: SECP256R1
Key size: 256
x: 1448598621669265146687495365245166001695582165426594859805879...
y: 3746487251185212638022777276660681179127648368273248695396648...
d: 2771254253714437992124662222726178157117638306617714749456695...

Private key: 
-----BEGIN EC PRIVATE KEY-----
MHcCAQEEID1EvkRMtGA9S5qvBZQZxFWcuPZTYC7Aidp0TJFP3q4QoAoGCCqGSM49
AwEHoUQDQgAEIAbHE7y/bPBxbPpqrMZPSJduPA3nYoysdnK2YDnm8ndS1F3LjovD
B7pr9xXvLj42Eqlk8EvVkrzlRcUzH56UMQ==
-----END EC PRIVATE KEY-----

Public key: 
-----BEGIN PUBLIC KEY-----
MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAEIAbHE7y/bPBxbPpqrMZPSJduPA3n
YoysdnK2YDnm8ndS1F3LjovDB7pr9xXvLj42Eqlk8EvVkrzlRcUzH56UMQ==
-----END PUBLIC KEY-----