The MinIO server runs a key-derivation algorithm to generate the KEK using a pseudo-random function ([PRF](#prf)):
`KEK := PRF(EK, IV, context_values)` where:

     *
     * @return the selectedCipher
     */
    public int getSelectedCipher() {
        return this.selectedCipher;
    }

    /**
     * Gets the pre-authentication integrity hash algorithm selected for SMB 3.1.1.
     *
     * @return the selectedPreauthHash
     */
    public int getSelectedPreauthHash() {
        return this.selectedPreauthHash;
    }

    /**

	BackendInfo() madmin.BackendInfo
	Legacy() bool // Only returns true for deployments which use CRCMOD as its object distribution algorithm.
	StorageInfo(ctx context.Context, metrics bool) StorageInfo
	LocalStorageInfo(ctx context.Context, metrics bool) StorageInfo

	// Bucket operations.

 * of {@code Graph} that provides methods for adding and removing nodes and edges. If you do not
 * need to mutate a graph (e.g. if you write a method than runs a read-only algorithm on the graph),
 * you should use the non-mutating {@link Graph} interface, or an {@link ImmutableGraph}.
 *
 * <p>You can create an immutable copy of an existing {@code Graph} using {@link
 * ImmutableGraph#copyOf(Graph)}:

 * of {@code Graph} that provides methods for adding and removing nodes and edges. If you do not
 * need to mutate a graph (e.g. if you write a method than runs a read-only algorithm on the graph),
 * you should use the non-mutating {@link Graph} interface, or an {@link ImmutableGraph}.
 *
 * <p>You can create an immutable copy of an existing {@code Graph} using {@link
 * ImmutableGraph#copyOf(Graph)}:

)

// newFileInfo - initializes new FileInfo, allocates a fresh erasure info.
func newFileInfo(object string, dataBlocks, parityBlocks int) (fi FileInfo) {
	fi.Erasure = ErasureInfo{
		Algorithm:    erasureAlgorithm,
		DataBlocks:   dataBlocks,
		ParityBlocks: parityBlocks,
		BlockSize:    blockSizeV2,
		Distribution: hashOrder(object, dataBlocks+parityBlocks),
	}
	return fi
}

], len1) return v } // gcmHashKey represents the 16-byte hash key required by the GHASH algorithm. type gcmHashKey [16]byte type gcmPlatformData struct { hashKey gcmHashKey } func initGCM(g *GCM) { if !useGCM && !useGHASH { return } // Note that hashKey is also used in the KMA codepath to hash large nonces. aes.EncryptBlockInternal(&g.cipher, g.hashKey[:], g.hashKey[:]) } // ghashAsm uses the GHASH algorithm to hash data with the given key. The initial // hash value is given by hash which will be...

```console
$ openssl rand -hex 32

09d25e094faa6ca2556c818166b7a9563b93f7099f6f0f4caa6cf63b88e8d3e7
```

</div>

然后，把生成的密钥复制到变量**SECRET_KEY**，注意，不要使用本例所示的密钥。

创建指定 JWT 令牌签名算法的变量 **ALGORITHM**，本例中的值为 `"HS256"`。

创建设置令牌过期时间的变量。

定义令牌端点响应的 Pydantic 模型。

创建生成新的访问令牌的工具函数。

{* ../../docs_src/security/tutorial004.py hl[6,12:14,28:30,78:86] *}

## 更新依赖项

   * page-replacement algorithm to determine which entries to evict when the capacity has been
   * exceeded.
   *
   * The page replacement algorithm's data structures are kept casually consistent with the map. The
   * ordering of writes to a segment is sequentially consistent. An update to the map and recording
   * of reads may not be immediately reflected on the algorithm's data structures. These structures

mapred.maxthreads.generate.mapoutput=2 # Num threads to write map outputs
mapred.maxthreads.partition.closer=0 # Asynchronous map flushers
mapreduce.fileoutputcommitter.algorithm.version=2 # Use the latest committer version
mapreduce.job.reduce.slowstart.completedmaps=0.99 # 99% map, then reduce
mapreduce.reduce.shuffle.input.buffer.percent=0.9 # Min % buffer in RAM