75b6419892259a9f6d7a1266962f318e08fb2d01.diff

diff --git a/chrome/updater/net/network_fetcher_win.cc b/chrome/updater/net/network_fetcher_win.cc
index 9b44987a8ddbc..c8092d28bdd0d 100644
--- a/chrome/updater/net/network_fetcher_win.cc
+++ b/chrome/updater/net/network_fetcher_win.cc
@@ -21,6 +21,7 @@
 #include "base/sequence_checker.h"
 #include "base/strings/sys_string_conversions.h"
 #include "base/strings/utf_string_conversions.h"
+#include "base/win/windows_version.h"
 #include "chrome/updater/net/network.h"
 #include "chrome/updater/policy/service.h"
 #include "chrome/updater/updater_scope.h"
@@ -37,6 +38,54 @@
 namespace updater {
 namespace {
 
+std::wstring FromCharOrEmpty(const wchar_t* str) {
+  return str ? std::wstring(str) : std::wstring();
+}
+
+// Wrapper for WINHTTP_CURRENT_USER_IE_PROXY_CONFIG structure.
+// According to MSDN, callers must free strings with GlobalFree.
+class ScopedIeProxyConfig {
+ public:
+  ScopedIeProxyConfig();
+  ScopedIeProxyConfig(const ScopedIeProxyConfig&) = delete;
+  ScopedIeProxyConfig& operator=(const ScopedIeProxyConfig&) = delete;
+  ~ScopedIeProxyConfig();
+
+  WINHTTP_CURRENT_USER_IE_PROXY_CONFIG* receive() { return &ie_proxy_config_; }
+
+  bool auto_detect() const { return ie_proxy_config_.fAutoDetect; }
+  std::wstring auto_config_url() const {
+    return FromCharOrEmpty(ie_proxy_config_.lpszAutoConfigUrl);
+  }
+  std::wstring proxy() const {
+    return FromCharOrEmpty(ie_proxy_config_.lpszProxy);
+  }
+  std::wstring proxy_bypass() const {
+    return FromCharOrEmpty(ie_proxy_config_.lpszProxyBypass);
+  }
+
+ private:
+  WINHTTP_CURRENT_USER_IE_PROXY_CONFIG ie_proxy_config_ = {};
+};
+
+ScopedIeProxyConfig::ScopedIeProxyConfig() {
+  ie_proxy_config_.fAutoDetect = false;
+  ie_proxy_config_.lpszAutoConfigUrl = nullptr;
+  ie_proxy_config_.lpszProxy = nullptr;
+  ie_proxy_config_.lpszProxyBypass = nullptr;
+}
+
+ScopedIeProxyConfig::~ScopedIeProxyConfig() {
+  if (ie_proxy_config_.lpszAutoConfigUrl)
+    ::GlobalFree(ie_proxy_config_.lpszAutoConfigUrl);
+
+  if (ie_proxy_config_.lpszProxy)
+    ::GlobalFree(ie_proxy_config_.lpszProxy);
+
+  if (ie_proxy_config_.lpszProxyBypass)
+    ::GlobalFree(ie_proxy_config_.lpszProxyBypass);
+}
+
 // Factory method for the proxy configuration strategy.
 scoped_refptr<winhttp::ProxyConfiguration> GetProxyConfiguration(
     std::optional<PolicyServiceProxyConfiguration>
@@ -53,7 +102,32 @@ scoped_refptr<winhttp::ProxyConfiguration> GetProxyConfiguration(
         L""});
   }
   VLOG(1) << "Using the system configuration for proxy.";
-  return base::MakeRefCounted<winhttp::AutoProxyConfiguration>();
+  const base::win::OSInfo* os_info = base::win::OSInfo::GetInstance();
+  const bool supports_automatic_proxy =
+      os_info->version() >= base::win::Version::WIN8_1;
+  if (supports_automatic_proxy) {
+    return base::MakeRefCounted<winhttp::AutoProxyConfiguration>();
+  }
+
+  ScopedImpersonation impersonate_user;
+  if (IsLocalSystemUser()) {
+    VLOG(2) << "Running as SYSTEM, impersonate the current user.";
+    base::win::ScopedHandle user_token = GetUserTokenFromCurrentSessionId();
+    if (user_token.IsValid()) {
+      impersonate_user.Impersonate(user_token.Get());
+    }
+  }
+
+  ScopedIeProxyConfig ie_proxy_config;
+  if (::WinHttpGetIEProxyConfigForCurrentUser(ie_proxy_config.receive())) {
+    return base::MakeRefCounted<winhttp::ProxyConfiguration>(winhttp::ProxyInfo{
+        ie_proxy_config.auto_detect(), ie_proxy_config.auto_config_url(),
+        ie_proxy_config.proxy(), ie_proxy_config.proxy_bypass()});
+  } else {
+    PLOG(ERROR) << "Failed to get proxy for current user";
+  }
+
+  return base::MakeRefCounted<winhttp::ProxyConfiguration>();
 }
 
 class NetworkFetcher : public update_client::NetworkFetcher {