Reland "[CrOS Printing] Don't send username and filename unencrypted"

This is a reland of 3e49c929

Original change's description:
> [CrOS Printing] Don't send username and filename unencrypted
>
> This situation may come up if policy was changed after printer was
> selected. We reject printing job since silently omitting username and
> filename could be confusing.
>
> Bug: 1042798
> Change-Id: Iba385503d8f7e960291728d6515ca7c236220847
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2004992
> Reviewed-by: Sean Kau <skau@chromium.org>
> Reviewed-by: Lei Zhang <thestig@chromium.org>
> Commit-Queue: Lei Zhang <thestig@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#734128}

TBR=thestig@chromium.org,skau@chromium.org,yoichio@chromium.org

Bug: 1042798
Change-Id: I75d30cc7c94d843cbbc32318907165bfede6df69
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2015029Reviewed-by: Vladislav Kuzkokov <vkuzkokov@chromium.org>
Commit-Queue: Vladislav Kuzkokov <vkuzkokov@chromium.org>
Cr-Commit-Position: refs/heads/master@{#734453}

printing/backend/cups_printer.cc

@@ -16,6 +16,7 @@
 
 namespace {
 
+const char kCUPSDeviceUri[] = "device-uri";
 const char kCUPSPrinterInfoOpt[] = "printer-info";
 const char kCUPSPrinterStateOpt[] = "printer-state";
 
@@ -123,6 +124,12 @@ std::string CupsPrinter::GetMakeAndModel() const {
   return make_and_model ? std::string(make_and_model) : std::string();
 }
 
+std::string CupsPrinter::GetUri() const {
+  const char* uri = cupsGetOption(kCUPSDeviceUri, destination_->num_options,
+                                  destination_->options);
+  return uri ? std::string(uri) : std::string();
+}
+
 bool CupsPrinter::EnsureDestInfo() const {
   if (dest_info_)
     return true;

printing/backend/cups_printer.h

@@ -77,6 +77,8 @@ class PRINTING_EXPORT CupsPrinter : public CupsOptionProvider {
 
   std::string GetMakeAndModel() const;
 
+  std::string GetUri() const;
+
   // Lazily initialize dest info as it can require a network call
   bool EnsureDestInfo() const;
 

printing/printing_context_chromeos.cc

@@ -356,6 +356,15 @@ PrintingContext::Result PrintingContextChromeos::UpdatePrinterSettings(
   SetPrintableArea(settings_.get(), media, true);
   cups_options_ = SettingsToCupsOptions(*settings_);
   send_user_info_ = settings_->send_user_info();
+  if (send_user_info_) {
+    DCHECK(printer_);
+    std::string uri_string = printer_->GetUri();
+    const base::StringPiece uri(uri_string);
+    if (!uri.starts_with("ipps:") && !uri.starts_with("https:") &&
+        !uri.starts_with("usb:") && !uri.starts_with("ippusb:")) {
+      return OnError();
+    }
+  }
   username_ = send_user_info_ ? settings_->username() : std::string();
 
   return OK;