From daec5ee13e63e83663986ea853f99a29c0782a1c Mon Sep 17 00:00:00 2001 From: Maybe Waffle Date: Sun, 3 Apr 2022 13:06:30 +0400 Subject: [PATCH] Hide bot token in errors This fixes a potential[^1] security vulnerability -- if bot shows errors from teloxide to the user & for some reason network error happened[^2] the url of the request would be included in the error. Since TBA includes bot token in the error this may lead to token leakage. This commit fixes that issue by removing the token from the urls of `reqwest::Error`, we try to only replace the token, but if we fail we remove the whole url. This can be tested by using a very low timeout value for the http reqwest client: ```rust let client = reqwest::Client::builder() .timeout(std::time::Duration::from_millis(1)) .build() .unwrap(); let bot = Bot::from_env_with_client(client).auto_send(); // see if the token is redacted when network error (timeout) happens // while sending common requests let _ = dbg!(bot.get_me().await); // see if the token is redacted when network error (timeout) happens // while downloading files ("path" is unimportant as the timeout is so // low the request probably won't even be sent) let _ = dbg!(bot.download_file_stream("path").next().await); ``` For me this gives the following result: ```text [t.rs:26] bot.get_me().await = Err( Network( reqwest::Error { kind: Request, url: Url { scheme: "https", cannot_be_a_base: false, username: "", password: None, host: Some( Domain( "api.telegram.org", ), ), port: None, path: "/token:redacted/GetMe", query: None, fragment: None, }, source: TimedOut, }, ), ) [t.rs:31] bot.download_file_stream("path").next().await = Some( Err( reqwest::Error { kind: Request, url: Url { scheme: "https", cannot_be_a_base: false, username: "", password: None, host: Some( Domain( "api.telegram.org", ), ), port: None, path: "/file/token:redacted/path", query: None, fragment: None, }, source: TimedOut, }, ), ) ``` Note that this commits parent is `d0be260` and not the current master the master branch currently contains breaking changes (we'll need to make a release from this brach directly). [^1]: Note that there are recorded cases where the token got exposed. [^2]: Note that this can be theoretically be controlled by the user when sending/downloading bigger files. --- CHANGELOG.md | 8 +++++++ Cargo.toml | 2 +- src/bot/download.rs | 1 + src/errors.rs | 58 ++++++++++++++++++++++++++++++++++++++++++--- src/net/request.rs | 18 ++++---------- 5 files changed, 70 insertions(+), 17 deletions(-) diff --git a/CHANGELOG.md b/CHANGELOG.md index e8c45682..caddfe38 100644 --- a/CHANGELOG.md +++ b/CHANGELOG.md @@ -7,6 +7,14 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0 ## unreleased +## 0.4.5 - 2022-04-03 + +### Fixed + +- Hide bot token in errors ([#200][200]) + +[200]: https://github.com/teloxide/teloxide-core/pull/200 + ## 0.4.4 - 2022-04-21 ### Added diff --git a/Cargo.toml b/Cargo.toml index b9ea7ec8..c672ab93 100644 --- a/Cargo.toml +++ b/Cargo.toml @@ -1,7 +1,7 @@ [package] name = "teloxide-core" description = "Core part of the `teloxide` library - telegram bot API client" -version = "0.4.4" +version = "0.4.5" edition = "2018" license = "MIT" diff --git a/src/bot/download.rs b/src/bot/download.rs index 5a98e488..4b07460b 100644 --- a/src/bot/download.rs +++ b/src/bot/download.rs @@ -41,6 +41,7 @@ impl<'w> Download<'w> for Bot { &self.token, path, ) + .map(|res| res.map_err(crate::errors::hide_token)) .boxed() } } diff --git a/src/errors.rs b/src/errors.rs index a0ac4567..ad3348dd 100644 --- a/src/errors.rs +++ b/src/errors.rs @@ -1,19 +1,19 @@ use std::io; -use derive_more::From; use serde::Deserialize; use thiserror::Error; /// An error caused by downloading a file. -#[derive(Debug, Error, From)] +#[derive(Debug, Error)] pub enum DownloadError { /// A network error while downloading a file from Telegram. #[error("A network error: {0}")] + // NOTE: this variant must not be created by anything except the From impl Network(#[source] reqwest::Error), /// An I/O error while writing a file to destination. #[error("An I/O error: {0}")] - Io(#[source] std::io::Error), + Io(#[from] std::io::Error), } /// An error caused by sending a request to Telegram. @@ -35,6 +35,7 @@ pub enum RequestError { /// Network error while sending a request to Telegram. #[error("A network error: {0}")] + // NOTE: this variant must not be created by anything except the From impl Network(#[source] reqwest::Error), /// Error while parsing a response from Telegram. @@ -727,3 +728,54 @@ pub enum ApiError { #[error("Unknown error: {0:?}")] Unknown(String), } + +impl From for DownloadError { + fn from(error: reqwest::Error) -> Self { + DownloadError::Network(hide_token(error)) + } +} + +impl From for RequestError { + fn from(error: reqwest::Error) -> Self { + RequestError::Network(hide_token(error)) + } +} + +/// Replaces token in the url in the error with `token:redacted` string. +pub(crate) fn hide_token(mut error: reqwest::Error) -> reqwest::Error { + let url = match error.url_mut() { + Some(url) => url, + None => return error, + }; + + if let Some(mut segments) = url.path_segments() { + // Usually the url looks like "bot/..." or "file/bot/...". + let (beginning, segment) = match segments.next() { + Some("file") => ("file/", segments.next()), + segment => ("", segment), + }; + + if let Some(token) = segment.and_then(|s| s.strip_prefix("bot")) { + // make sure that what we are about to delete looks like a bot token + if let Some((id, secret)) = token.split_once(':') { + if secret.len() >= 35 + && secret + .chars() + .all(|c| c.is_ascii_alphanumeric() || c == '-' || c == '_') + && id.chars().all(|c| c.is_ascii_digit()) + { + // found token, hide only the token + let without_token = + &url.path()[(beginning.len() + "/bot".len() + token.len())..]; + let redacted = format!("{beginning}token:redacted{without_token}"); + + url.set_path(&redacted); + return error; + } + } + } + } + + // couldn't find token in the url, hide the whole url + error.without_url() +} diff --git a/src/net/request.rs b/src/net/request.rs index 3730857e..1b2273cd 100644 --- a/src/net/request.rs +++ b/src/net/request.rs @@ -37,18 +37,14 @@ where let request = client .post(crate::net::method_url(api_url, token, method_name)) .multipart(params) - .build() - .map_err(RequestError::Network)?; + .build()?; // FIXME: uncomment this, when reqwest starts setting default timeout early // if let Some(timeout) = timeout_hint { // *request.timeout_mut().get_or_insert(Duration::ZERO) += timeout; // } - let response = client - .execute(request) - .await - .map_err(RequestError::Network)?; + let response = client.execute(request).await?; process_response(response).await } @@ -81,18 +77,14 @@ where .post(crate::net::method_url(api_url, token, method_name)) .header(CONTENT_TYPE, HeaderValue::from_static("application/json")) .body(params) - .build() - .map_err(RequestError::Network)?; + .build()?; // FIXME: uncomment this, when reqwest starts setting default timeout early // if let Some(timeout) = timeout_hint { // *request.timeout_mut().get_or_insert(Duration::ZERO) += timeout; // } - let response = client - .execute(request) - .await - .map_err(RequestError::Network)?; + let response = client.execute(request).await?; process_response(response).await } @@ -105,7 +97,7 @@ where tokio::time::sleep(DELAY_ON_SERVER_ERROR).await; } - let text = response.text().await.map_err(RequestError::Network)?; + let text = response.text().await?; serde_json::from_str::>(&text) .map_err(|source| RequestError::InvalidJson {