hmac.words.slice
时间: 2023-12-23 07:27:53 浏览: 37
`hmac.words.slice`是一个方法,用于从`hmac.words`数组中提取指定范围的元素,并返回一个新的数组。该方法的语法如下:
```javascript
hmac.words.slice(start, end)
```
其中,`start`是起始索引(包含),`end`是结束索引(不包含)。如果省略`end`参数,则会提取从`start`索引到数组末尾的所有元素。
以下是一个示例:
```javascript
var hmac = {
words: [1, 2, 3, 4, 5]
};
var slicedArray = hmac.words.slice(1, 4);
console.log(slicedArray); // 输出:[2, 3, 4]
```
在上面的示例中,`hmac.words`数组包含了5个元素。通过调用`slice`方法,我们提取了索引1到索引3的元素(不包括索引3),并将结果存储在`slicedArray`中。最后,我们打印了`slicedArray`的值,输出为`[2, 3, 4]`。
相关问题
openssl/hmac.h提供一下
内容:
#ifndef OPENSSL_HEADER_HMAC_H
#define OPENSSL_HEADER_HMAC_H
#include <openssl/macros.h>
#if defined(__cplusplus)
extern "C" {
#endif
/* HMAC functions */
/* HMAC_Init_ex sets up |ctx| to use |key| as the key for HMAC and |md| as the
* hash function. It returns one. */
OPENSSL_EXPORT int HMAC_Init_ex(HMAC_CTX *ctx, const void *key, size_t key_len,
const EVP_MD *md, ENGINE *impl);
/* HMAC_Init sets up |ctx| to use |key| as the key for HMAC and |md| as the hash
* function. It returns one. */
OPENSSL_EXPORT int HMAC_Init(HMAC_CTX *ctx, const void *key, size_t key_len,
const EVP_MD *md);
/* HMAC_Update hashes |len| bytes from |data| into the current HMAC context. It
* returns one. */
OPENSSL_EXPORT int HMAC_Update(HMAC_CTX *ctx, const void *data, size_t len);
/* HMAC_Final writes the HMAC of the data passed to |HMAC_Update| into |out|
* and clears |ctx|. It returns one. */
OPENSSL_EXPORT int HMAC_Final(HMAC_CTX *ctx, uint8_t *out, unsigned int *out_len);
/* HMAC takes the given hash function, |md|, computes the HMAC of |len| bytes
* from |data| with |key_len| bytes from |key| and writes the HMAC to |out|. It
* returns |out| or NULL on error. */
OPENSSL_EXPORT uint8_t *HMAC(const EVP_MD *md, const void *key, size_t key_len,
const uint8_t *data, size_t len, uint8_t *out,
unsigned int *out_len);
/* HMAC_CTX_copy copies |in| into |out|. It returns one. */
OPENSSL_EXPORT int HMAC_CTX_copy(HMAC_CTX *out, const HMAC_CTX *in);
/* HMAC_CTX_free frees any memory used by |ctx|. */
OPENSSL_EXPORT void HMAC_CTX_free(HMAC_CTX *ctx);
#if defined(__cplusplus)
} /* extern C */
#endif
#endif /* OPENSSL_HEADER_HMAC_H */
try: h.hexverify(hmac.hex()) return True except: return False
As an AI language model, I do not have enough context to fully understand the purpose of this code snippet. However, based on what is provided, it appears to be a function that takes a key and message and checks if the HMAC (Hash-based Message Authentication Code) is valid.
The "try-except" block is used to catch any exceptions that may be thrown during the verification process. If the verification is successful, the function returns True. If an exception is caught or the verification fails, the function returns False.