OpenSSL 4.1.0 shipped today. I built it and measured ML-KEM, ML-DSA, and DTLS 1.3

说明与用途

OpenSSL 4.1.0 引入 DTLS 1.3 和后量子 ML‑KEM/ML‑DSA 支持。构建和测试显示 ML‑KEM‑768 生成密钥比 RSA‑2048 快约 1200 倍，而 ML‑DSA‑65 签名更快但验证更慢。密钥和签名尺寸显著增大，带宽成为新的瓶颈。

问题

Deploying DTLS 1.3 and post‑quantum algorithms requires understanding new features, performance, and known issues in OpenSSL 4.1.0.

结果

DTLS 1.3 handshakes succeed; ML‑KEM keygen is ~1,200× faster than RSA‑2048; ML‑DSA‑65 signing is faster but verifying is slower than RSA‑2048; key and signature sizes are significantly larger, making bandwidth the new bottleneck.

工作流

• Download OpenSSL 4.1.0 source tarball
• Configure with no-shared no-tests and -O3
• Build on a real disk to avoid /tmp space limits
• Run DTLS 1.3 handshake test with s_server -dtls1_3 and s_client -dtls1_3
• Measure post‑quantum performance with openssl speed
• Generate keys and signatures to assess byte sizes
• Review release notes for known DTLS issues
• Plan deployment based on handshake paths used

证据

DTLS 1.3 negotiates — and 3.0 can't even parse the flag

ML-KEM-768 keygen 16345.9 29921.6 19203.1

ML-DSA-65 verify 13598.3

ML-DSA-65 signature on a 10-byte message: 3309 bytes

The system 3.0.13 knows zero post-quantum algorithms