PHP访问受保护资源：从401未授权到HTTP Digest认证的实践指南

<?php
// 示例 v1: 直接在URL中嵌入凭据
$url_with_credentials = "http://admin:441e3!@192.168.1.90/ISAPI/Streaming/channels/201/picture?videoResolutionWidth=1920&videoResolutionHeight=1080";
$data = file_get_contents($url_with_credentials);

if ($data === false) {
    echo "ERROR: file_get_contents failed. Check server logs for 401 Unauthorized.\n";
} else {
    header('Content-type: image/jpeg');
    echo $data;
}
?>

<?php
// 示例 v2: 使用 stream_context_create 进行 Basic 认证
$username = 'admin';
$password = '441e3!';
$url = 'http://192.168.1.90/ISAPI/Streaming/channels/201/picture?videoResolutionWidth=1920&videoResolutionHeight=1080';

$context = stream_context_create(array(
    'http' => array(
        'header'  => "Authorization: Basic " . base64_encode("$username:$password")
    )
));
$data = file_get_contents($url, false, $context);

if ($data === false) {
    echo "ERROR: file_get_contents with Basic auth failed. Check server logs for 401 Unauthorized.\n";
} else {
    header('Content-type: image/jpeg');
    echo $data;
}
?>

<?php
// 示例 v3 (原始): 使用 cURL 进行 Basic 认证
$login = 'admin';
$password = '441e3!';
$url = 'http://192.168.1.90/ISAPI/Streaming/channels/201/picture?videoResolutionWidth=1920&videoResolutionHeight=1080';

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_HTTPAUTH, CURLAUTH_BASIC); // 指定 Basic 认证
curl_setopt($ch, CURLOPT_USERPWD, "$login:$password");
$data = curl_exec($ch);

if ($data === false) {
    echo 'ERROR: ' . curl_error($ch) . "\n";
} else {
    header('Content-type: image/jpeg');
    echo $data;
}
curl_close($ch);
?>

Authentication selected: Digest realm="da9ea0f8f352408658c64b0a", domain="::", qop="auth", nonce="e1f5166b2054a18a2a17595a4bbfaf23:1635894137125", opaque="", algorithm="MD5", stale="FALSE"
...
HTTP request sent, awaiting response... 200 OK

<?php
// 最终解决方案: 使用 cURL 进行 HTTP Digest 认证
$login = 'admin';
$password = '441e3!';
$url = 'http://192.168.1.90/ISAPI/Streaming/channels/201/picture?videoResolutionWidth=1920&videoResolutionHeight=1080';

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_HTTPAUTH, CURLAUTH_DIGEST); // 关键：指定 Digest 认证
curl_setopt($ch, CURLOPT_USERPWD, "$login:$password");
// 可选：如果遇到SSL/TLS证书问题，可以添加以下两行，但在生产环境应谨慎使用
// curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
// curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false);

$data = curl_exec($ch);

// 错误处理：检查 cURL 执行是否成功
if ($data === false) {
    echo 'ERROR: ' . curl_error($ch) . "\n"; // 输出 cURL 错误信息
    // 进一步诊断：可以获取 HTTP 状态码
    $http_code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
    echo 'HTTP Status Code: ' . $http_code . "\n";
} else {
    // 成功获取数据，设置正确的 Content-Type 并输出
    header('Content-type: image/jpeg');
    echo $data;
}

curl_close($ch);
?>