ハッシュアルゴリズムの比較
MD5、SHA-1、SHA-256、SHA-3、BLAKE2/3 を速度、セキュリティ、ユースケースの観点から比較します。
问题
ハッシュアルゴリズムを選ぶ必要がありますが、各選択肢の速度とセキュリティの比較がよくわかりません。
前提条件
- ハッシュ関数の理解
- セキュリティ要件に関する知識
ステップ
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1. Review the security status
MD5 is broken (collisions in seconds). SHA-1 is broken (SHAttered attack). SHA-256 is secure and widely used. SHA-3 (Keccak) is secure and structurally different from SHA-2. BLAKE2/3 are secure and faster than SHA-2. Choose based on your security needs.
入力algorithms: MD5, SHA-1, SHA-256, SHA-3, BLAKE3输出secure: SHA-256, SHA-3, BLAKE3 -
2. Compare performance
BLAKE3 is the fastest, followed by BLAKE2, then SHA-256 (with hardware acceleration), then SHA-3. MD5 and SHA-1 are fast but broken. For high-throughput hashing, BLAKE3 is the best choice. For compatibility, SHA-256 is the safest bet.
入力1 GB file输出BLAKE3: ~1 GB/s | SHA-256: ~500 MB/s -
3. Choose based on context
Use SHA-256 for general-purpose hashing and compatibility. Use SHA-3 for NIST compliance or resistance to length-extension attacks. Use BLAKE3 for maximum speed. Use CRC32 only for non-security checksums. Never use MD5 or SHA-1 for security.
入力general purpose输出SHA-256
期待される結果
セキュリティ、速度、互換性の要件に基づいた、十分な根拠のあるハッシュアルゴリズムの選択。
よくあるエラー
- Choosing MD5 for speed in a security context
- MD5 is broken. Use BLAKE3 if you need speed with security, or SHA-256 for compatibility.
- Using SHA-256 where length-extension resistance is needed
- SHA-256 is vulnerable to length-extension attacks. Use SHA-3 or HMAC-SHA-256 if this matters.
トラブルシューティング指引
- If speed is critical, benchmark BLAKE3 against SHA-256 with hardware acceleration on your target platform.
- For FIPS compliance, use SHA-256 or SHA-3 only; BLAKE is not FIPS-approved.
セキュリティ上の制限
- Only use hash algorithms that are currently considered secure. MD5 and SHA-1 must not be used for security.
- All hashing is local.