Created
November 20, 2025 09:45
-
-
Save mydreambei-ai/5c81827bc41b49fc814cf9c649a7bced to your computer and use it in GitHub Desktop.
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| from cryptography.hazmat.primitives.asymmetric import ec | |
| from cryptography.hazmat.primitives.kdf.hkdf import HKDF | |
| from cryptography.hazmat.primitives import hashes | |
| from cryptography.hazmat.primitives.serialization import Encoding, PublicFormat | |
| # ---------------------------- | |
| # 1. 客户端生成 ECDH ephemeral key | |
| # ---------------------------- | |
| client_private_key = ec.generate_private_key(ec.SECP256R1()) | |
| client_public_key = client_private_key.public_key() | |
| # ---------------------------- | |
| # 2. 服务器生成 ECDH ephemeral key | |
| # ---------------------------- | |
| server_private_key = ec.generate_private_key(ec.SECP256R1()) | |
| server_public_key = server_private_key.public_key() | |
| # ---------------------------- | |
| # 3. 交换公钥（在真实 TLS 中通过明文 ServerHello/ClientHello） | |
| # ---------------------------- | |
| client_pub_bytes = client_public_key.public_bytes(Encoding.X962, PublicFormat.UncompressedPoint) | |
| server_pub_bytes = server_public_key.public_bytes(Encoding.X962, PublicFormat.UncompressedPoint) | |
| # ---------------------------- | |
| # 4. 客户端计算 shared secret | |
| # ---------------------------- | |
| peer_server_pub = ec.EllipticCurvePublicKey.from_encoded_point(ec.SECP256R1(), server_pub_bytes) | |
| shared_secret_client = client_private_key.exchange(ec.ECDH(), peer_server_pub) | |
| # ---------------------------- | |
| # 5. 服务器计算 shared secret | |
| # ---------------------------- | |
| peer_client_pub = ec.EllipticCurvePublicKey.from_encoded_point(ec.SECP256R1(), client_pub_bytes) | |
| shared_secret_server = server_private_key.exchange(ec.ECDH(), peer_client_pub) | |
| assert shared_secret_client == shared_secret_server # 确认共享密钥一致 | |
| # ---------------------------- | |
| # 6. 派生 handshake keys（HKDF） | |
| # ---------------------------- | |
| # 模拟 TLS 1.3: early_secret = 0 (无 PSK) | |
| early_secret = b'\x00' * hashes.SHA256().digest_size | |
| # handshake_secret = HKDF-Extract(early_secret, shared_secret) | |
| hkdf_extract = HKDF( | |
| algorithm=hashes.SHA256(), | |
| length=32, | |
| salt=early_secret, | |
| info=None, | |
| ) | |
| handshake_secret = hkdf_extract.derive(shared_secret_client) | |
| # 派生 client/server handshake traffic key | |
| client_hs_key = HKDF( | |
| algorithm=hashes.SHA256(), | |
| length=32, | |
| salt=None, | |
| info=b"c hs traffic", | |
| ).derive(handshake_secret) | |
| server_hs_key = HKDF( | |
| algorithm=hashes.SHA256(), | |
| length=32, | |
| salt=None, | |
| info=b"s hs traffic", | |
| ).derive(handshake_secret) | |
| print("Client handshake key:", client_hs_key.hex()) | |
| print("Server handshake key:", server_hs_key.hex()) |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment