detect some legacy Windows versions and return legacy update version

should allow to serve old desktop client versions to legacy operating
systems

Signed-off-by: Matthieu Gallien <matthieu_gallien@yahoo.fr>

3 files changed, 60 insertions, 0 deletions

diff --git a/config/config.php b/config/config.php
index 2f9e847..736e691 100644
--- a/config/config.php
+++ b/config/config.php
@@ -23,18 +23,24 @@ declare(strict_types=1);
 
 $rel = '2021-04-29 16:00';
 $ver = '3.2.1';
+$legacy_ver = '3.1.3';
 
 $ver_str = 'Nextcloud Client ' . $ver;
+$legacy_ver_str = 'Nextcloud Client ' . $legacy_ver;
 
 if (version_compare($version, '3.0.3') < 0) {
 	$url = 'https://download.nextcloud.com/desktop/releases/';
+	$legacyurl = 'https://download.nextcloud.com/desktop/releases/';
 	$linux_url = $url . 'Linux/';
 	$windows_url = $url . 'Windows/';
+	$legacy_windows_url = $legacyurl;
 	$mac_url = $url . 'Mac/Installer/';
 } else {
 	$url = 'https://github.com/nextcloud/desktop/releases/download/v' . $ver . '/';
+	$legacyurl = 'https://github.com/nextcloud/desktop/releases/download/v' . $legacy_ver . '/';
 	$linux_url = $url;
 	$windows_url = $url;
+	$legacy_windows_url = $legacyurl;
 	$mac_url = $url;
 }
 
@@ -58,19 +64,28 @@ return [
 		'linux' => [
 			'version' => $ver,
 			'versionstring' => $ver_str,
+			'legacyversion' => null,
+			'legacyversionstring' => null,
 			'downloadurl' => $linux_url . 'Nextcloud-' . $ver . '-x86_64.AppImage',
+			'legacydownloadurl' => null,
 			'web' => 'https://nextcloud.com/install/?pk_campaign=clientupdate#install-clients',
 		],
 		'win32' => [
 			'version' => $ver,
 			'versionstring' => $ver_str,
+			'legacyversion' => $legacy_ver,
+			'legacyversionstring' => $legacy_ver_str,
 			'downloadurl' => $windows_url . 'Nextcloud-' . $ver . $windows_suffix,
+			'legacydownloadurl' => $legacy_windows_url . 'Nextcloud-' . $legacy_ver . $windows_suffix,
 			'web' => 'https://nextcloud.com/install/?pk_campaign=clientupdate#install-clients',
 		],
 		'macos' => [
 			'version' => $ver,
 			'versionstring' => $ver_str,
+			'legacyversion' => null,
+			'legacyversionstring' => null,
 			'downloadurl' => $mac_url . 'Nextcloud-' . $ver . '.pkg',
+			'legacydownloadurl' => null,
 			'web' => 'https://nextcloud.com/install/?pk_campaign=clientupdate#install-clients',
 		],
 	],
diff --git a/index.php b/index.php
index fa568e6..0b6bd84 100644
--- a/index.php
+++ b/index.php
@@ -86,6 +86,9 @@ $currentArch = isset($_GET['currentArch']) ? (string)$_GET['currentArch'] : "x86
 $version = isset($_GET['version']) ? (string)$_GET['version'] : null;
 $isSparkle = isset($_GET['sparkle']) ? true : false;
 $updateSegment = isset($_GET['updatesegment']) ? (int)$_GET['updatesegment'] : -1;
+$osRelease = isset($_GET['osRelease']) ? (string)$_GET['osRelease'] : '';
+$osVersion = isset($_GET['osVersion']) ? (string)$_GET['osVersion'] : '';
+$kernelVersion = isset($_GET['kernelVersion']) ? (string)$_GET['kernelVersion'] : '';
 
 if($oem === null || $platform === null || $version === null) {
 	die();
@@ -100,6 +103,9 @@ $response = new \ClientUpdateServer\Response(
 	$version,
 	$isSparkle,
 	$updateSegment,
+	$osRelease,
+	$osVersion,
+	$kernelVersion,
 	$config
 );
 echo $response->buildResponse();
diff --git a/src/Response.php b/src/Response.php
index edec1a3..d8b1dd2 100644
--- a/src/Response.php
+++ b/src/Response.php
@@ -33,6 +33,12 @@ class Response {
 	private $isSparkle;
 	/** @var int */
 	private $updateSegment;
+	/** @var string */
+	private $osRelease;
+	/** @var string */
+	private $osVersion;
+	/** @var string */
+	private $kernelVersion;
 	/** @var array */
 	private $config;
 
@@ -41,12 +47,18 @@ class Response {
 								string $version,
 								bool $isSparkle,
 								int $updateSegment,
+								string $osRelease,
+								string $osVersion,
+								string $kernelVersion,
 								array $config) {
 		$this->oem = $oem;
 		$this->platform = $platform;
 		$this->version = $version;
 		$this->isSparkle = $isSparkle;
 		$this->updateSegment = $updateSegment;
+		$this->osRelease = $osRelease;
+		$this->osVersion = $osVersion;
+		$this->kernelVersion = $kernelVersion;
 		$this->config = $config;
 	}
 
@@ -89,12 +101,39 @@ class Response {
 			$this->updateSegment = random_int(0, 99);
 		}
 
+		$useNewerVersion = true;
+		if ($this->platform === 'win32') {
+			if ($this->osVersion === '10') {
+				switch ($this->kernelVersion) {
+				case '10.0.10240':
+				case '10.0.10586':
+				case '10.0.14393':
+				case '10.0.15063':
+				case '':
+					$useNewerVersion = false;
+					break;
+				}
+			} else {
+				$useNewerVersion = false;
+			}
+		}
+
 		// updateSegment is 0-99, so even fine grained control would possible
 		$chunks = floor($this->updateSegment / 10);
 		$throttleDate->sub(new \DateInterval('PT' . (12 * $chunks) . 'H'));
 
 		if ($throttleDate >= $releaseDate) {
 			$values = $this->config[$this->oem][$this->platform];
+
+			if ($useNewerVersion === false) {
+				$values['version'] = $values['legacyversion'];
+				$values['versionstring'] = $values['legacyversionstring'];
+				$values['downloadurl'] = $values['legacydownloadurl'];
+			}
+			unset($values['legacyversion']);
+			unset($values['legacyversionstring']);
+			unset($values['legacydownloadurl']);
+
 			if(version_compare($this->version, $values['version']) === -1) {
 				return $values;
 			}