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checkServerIdentity - node__tls.d.ts - Node documentation
function checkServerIdentity

Usage in Deno

```typescript import { checkServerIdentity } from "node:node__tls.d.ts"; ```
checkServerIdentity(
hostname: string,
): Error | undefined
Verifies the certificate `cert` is issued to `hostname`. Returns [Error](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error) object, populating it with `reason`, `host`, and `cert` on failure. On success, returns [undefined](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Undefined_type). This function is intended to be used in combination with the`checkServerIdentity` option that can be passed to [connect](../.././node__tls.d.ts/~/connect) and as such operates on a `certificate object`. For other purposes, consider using `x509.checkHost()` instead. This function can be overwritten by providing an alternative function as the `options.checkServerIdentity` option that is passed to `tls.connect()`. The overwriting function can call `tls.checkServerIdentity()` of course, to augment the checks done with additional verification. This function is only called if the certificate passed all other checks, such as being issued by trusted CA (`options.ca`). Earlier versions of Node.js incorrectly accepted certificates for a given`hostname` if a matching `uniformResourceIdentifier` subject alternative name was present (see [CVE-2021-44531](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-44531)). Applications that wish to accept`uniformResourceIdentifier` subject alternative names can use a custom `options.checkServerIdentity` function that implements the desired behavior.

Parameters

hostname: string
The host name or IP address to verify the certificate against.
A `certificate object` representing the peer's certificate.

Return Type

Error | undefined