PowerShell HttpClient ServerCertificateCustomValidationCallback demo

httpclient-demo.ps1

$cscode = @"
using System;
using System.Net.Http;
using System.Net.Security;
using System.Security.Cryptography;
using System.Security.Cryptography.X509Certificates;
using System.Text;

public class My {

    private static SHA256 sha256 = SHA256.Create();

    private static string bin2hex(byte[] ba) {
        var sb = new StringBuilder();
        foreach (byte b in ba) {
            sb.Append(b.ToString("x2"));
        }
        return sb.ToString();
    }

    public static Func<HttpRequestMessage, X509Certificate2, X509Chain, SslPolicyErrors, bool> GetServerCertificateValidationCallback(string expect = null) {
        if (null == expect) {
            return (sender, cert, chain, errors) => true;
        }
        expect = expect.ToUpper();
        return (sender, cert, chain, errors) => {
            var hash = sha256.ComputeHash(cert.GetRawCertData());
            var actual = bin2hex(hash).ToUpper();
            return string.Equals(expect, actual);
        };
    }
}
"@
Add-Type $cscode

$httpClientHandler = New-Object System.Net.Http.HttpClientHandler
$httpClient = New-Object System.Net.Http.HttpClient($httpClientHandler)

function http() {
    param(
        [Parameter(Mandatory=$true)] [System.Net.Http.HttpMethod] $method,
        [Parameter(Mandatory=$true)] [System.Uri] $uri,
        [Parameter(Mandatory=$false)] [Action[System.Net.Http.Headers.HttpRequestHeaders]] $headersAction,
        [Parameter(Mandatory=$false)] [System.Net.Http.HttpContent] $content
    )
    $request = New-Object System.Net.Http.HttpRequestMessage($method, $uri)
    $headersAction.Invoke($request.Headers)
    $request.Content = $content

    $httpClientHandler.ServerCertificateCustomValidationCallback = [My]::GetServerCertificateValidationCallback();
    $httpClientHandler.SslProtocols = [System.Security.Authentication.SslProtocols]::Tls11 -bor [System.Security.Authentication.SslProtocols]::Tls12

    $future = $httpClient.SendAsync($request)
    $response = $future.Result
    if ($null -eq $response) {
        Write-Error $future.Exception
        return $null
    }
    return $response
}

function get($url) {
    $method = New-Object System.Net.Http.HttpMethod("GET")
    $uri = New-Object System.Uri($url)
    $headersAction = {
        param([System.Net.Http.Headers.HttpRequestHeaders]$headers)
        $headers.Add('Host', "cn.bing.com")
        $headers.Add('User-Agent', "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.131 Safari/537.36")
        $headers.Add('Accept', 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8')
        $headers.Add('Accept-Language', 'en-US')
    }
    $content = New-Object System.Net.Http.StringContent('', [System.Text.Encoding]::UTF8)
    $response = http $method $uri $headersAction $content
    if ($null -eq $response) {
        return -1
    }
    Write-Output $response.StatusCode
    Write-Output $response.Content.ReadAsStringAsync().Result
    $response.Dispose()
    return 0
}

get "https://cn.bing.com/"