diff options
Diffstat (limited to 'toolkit/mozapps/defaultagent/rust/src/lib.rs')
| -rw-r--r-- | toolkit/mozapps/defaultagent/rust/src/lib.rs | 166 |
1 files changed, 166 insertions, 0 deletions
diff --git a/toolkit/mozapps/defaultagent/rust/src/lib.rs b/toolkit/mozapps/defaultagent/rust/src/lib.rs new file mode 100644 index 0000000000..de5f1ba03a --- /dev/null +++ b/toolkit/mozapps/defaultagent/rust/src/lib.rs @@ -0,0 +1,166 @@ +/* -*- Mode: rust; rust-indent-offset: 4 -*- */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#![allow(non_snake_case)] + +use std::ffi::{CStr, OsString}; +use std::os::raw::c_char; + +#[macro_use] +extern crate serde_derive; +#[macro_use] +extern crate log; +use winapi::shared::ntdef::HRESULT; +use winapi::shared::winerror::{HRESULT_FROM_WIN32, S_OK}; +use wio::wide::FromWide; + +mod viaduct_wininet; +use viaduct_wininet::WinInetBackend; + +// HRESULT with 0x80000000 is an error, 0x20000000 set is a customer error code. +#[allow(overflowing_literals)] +const HR_NETWORK_ERROR: HRESULT = 0x80000000 | 0x20000000 | 0x1; +#[allow(overflowing_literals)] +const HR_SETTINGS_ERROR: HRESULT = 0x80000000 | 0x20000000 | 0x2; + +#[derive(Debug, Deserialize)] +pub struct EnabledRecord { + // Unknown fields are ignored by serde: see the docs for `#[serde(deny_unknown_fields)]`. + pub(crate) enabled: bool, +} + +pub enum Error { + /// A backend error with an attached Windows error code from `GetLastError()`. + WindowsError(u32), + + /// A network or otherwise transient error. + NetworkError, + + /// A configuration or settings data error that probably requires code, configuration, or + /// server-side changes to address. + SettingsError, +} + +impl From<viaduct::UnexpectedStatus> for Error { + fn from(_err: viaduct::UnexpectedStatus) -> Self { + Error::NetworkError + } +} + +impl From<viaduct::Error> for Error { + fn from(err: viaduct::Error) -> Self { + match err { + viaduct::Error::NetworkError(_) => Error::NetworkError, + viaduct::Error::BackendError(raw) => { + // If we have a string that's a hex error code like + // "0xabcde", that's a Windows error. + if raw.starts_with("0x") { + let without_prefix = raw.trim_start_matches("0x"); + let parse_result = u32::from_str_radix(without_prefix, 16); + if let Ok(parsed) = parse_result { + return Error::WindowsError(parsed); + } + } + Error::SettingsError + } + _ => Error::SettingsError, + } + } +} + +impl From<serde_json::Error> for Error { + fn from(_err: serde_json::Error) -> Self { + Error::SettingsError + } +} + +impl From<url::ParseError> for Error { + fn from(_err: url::ParseError) -> Self { + Error::SettingsError + } +} + +fn is_agent_remote_disabled<S: AsRef<str>>(url: S) -> Result<bool, Error> { + // Be careful setting the viaduct backend twice. If the backend + // has been set already, assume that it's our backend: we may as + // well at least try to continue. + match viaduct::set_backend(&WinInetBackend) { + Ok(_) => {} + Err(viaduct::Error::SetBackendError) => {} + e => e?, + } + + let url = url::Url::parse(url.as_ref())?; + let req = viaduct::Request::new(viaduct::Method::Get, url); + let resp = req.send()?; + + let resp = resp.require_success()?; + + let body: serde_json::Value = resp.json()?; + let data = body.get("data").ok_or(Error::SettingsError)?; + let record: EnabledRecord = serde_json::from_value(data.clone())?; + + let disabled = !record.enabled; + Ok(disabled) +} + +// This is an easy way to consume `MOZ_APP_DISPLAYNAME` from Rust code. +extern "C" { + static gWinEventLogSourceName: *const u16; +} + +#[allow(dead_code)] +#[no_mangle] +extern "C" fn IsAgentRemoteDisabledRust(szUrl: *const c_char, lpdwDisabled: *mut u32) -> HRESULT { + let wineventlog_name = unsafe { OsString::from_wide_ptr_null(gWinEventLogSourceName) }; + let logger = wineventlog::EventLogger::new(&wineventlog_name); + // It's fine to initialize logging twice. + let _ = log::set_boxed_logger(Box::new(logger)); + log::set_max_level(log::LevelFilter::Info); + + // Use an IIFE for `?`. + let disabled_result = (|| { + if lpdwDisabled.is_null() { + return Err(Error::SettingsError); + } + + let url = unsafe { CStr::from_ptr(szUrl).to_str().map(|x| x.to_string()) } + .map_err(|_| Error::SettingsError)?; + + info!("Using remote settings URL: {}", url); + + is_agent_remote_disabled(url) + })(); + + match disabled_result { + Err(e) => { + return match e { + Error::WindowsError(errno) => { + let hr = HRESULT_FROM_WIN32(errno); + error!("Error::WindowsError({}) (HRESULT: 0x{:x})", errno, hr); + hr + } + Error::NetworkError => { + let hr = HR_NETWORK_ERROR; + error!("Error::NetworkError (HRESULT: 0x{:x})", hr); + hr + } + Error::SettingsError => { + let hr = HR_SETTINGS_ERROR; + error!("Error::SettingsError (HRESULT: 0x{:x})", hr); + hr + } + }; + } + + Ok(remote_disabled) => { + // We null-checked `lpdwDisabled` earlier, but just to be safe. + if !lpdwDisabled.is_null() { + unsafe { *lpdwDisabled = if remote_disabled { 1 } else { 0 } }; + } + return S_OK; + } + } +} |