From 3e67a3486eed22522f4352503ef7067ca81a8050 Mon Sep 17 00:00:00 2001 From: Rutger Broekhoff Date: Thu, 11 Jul 2024 19:11:51 +0200 Subject: Split server code into multiple smaller modules --- gitolfs3-server/src/api.rs | 279 +++++++++++ gitolfs3-server/src/authz.rs | 182 +++++++ gitolfs3-server/src/config.rs | 122 +++++ gitolfs3-server/src/dlimit.rs | 73 +++ gitolfs3-server/src/handler.rs | 455 +++++++++++++++++ gitolfs3-server/src/main.rs | 1087 +--------------------------------------- 6 files changed, 1128 insertions(+), 1070 deletions(-) create mode 100644 gitolfs3-server/src/api.rs create mode 100644 gitolfs3-server/src/authz.rs create mode 100644 gitolfs3-server/src/config.rs create mode 100644 gitolfs3-server/src/dlimit.rs create mode 100644 gitolfs3-server/src/handler.rs (limited to 'gitolfs3-server') diff --git a/gitolfs3-server/src/api.rs b/gitolfs3-server/src/api.rs new file mode 100644 index 0000000..dba7ada --- /dev/null +++ b/gitolfs3-server/src/api.rs @@ -0,0 +1,279 @@ +use std::collections::HashMap; + +use axum::{ + async_trait, + extract::{rejection, FromRequest, FromRequestParts, Request}, + http::{header, request::Parts, HeaderValue, StatusCode}, + response::{IntoResponse, Response}, + Extension, Json, +}; +use chrono::{DateTime, Utc}; +use gitolfs3_common::{Oid, Operation}; +use serde::{de::DeserializeOwned, Deserialize, Serialize}; + +pub const REPO_NOT_FOUND: GitLfsErrorResponse = + make_error_resp(StatusCode::NOT_FOUND, "Repository not found"); + +#[derive(Clone)] +pub struct RepositoryName(pub String); + +pub struct RepositoryNameRejection; + +impl IntoResponse for RepositoryNameRejection { + fn into_response(self) -> Response { + (StatusCode::INTERNAL_SERVER_ERROR, "Missing repository name").into_response() + } +} + +#[async_trait] +impl FromRequestParts for RepositoryName { + type Rejection = RepositoryNameRejection; + + async fn from_request_parts(parts: &mut Parts, state: &S) -> Result { + let Ok(Extension(repo_name)) = Extension::::from_request_parts(parts, state).await + else { + return Err(RepositoryNameRejection); + }; + Ok(repo_name) + } +} + +#[derive(Debug, Serialize, Deserialize, PartialEq, Eq, Clone, Copy)] +pub enum TransferAdapter { + #[serde(rename = "basic")] + Basic, + #[serde(other)] + Unknown, +} + +#[derive(Debug, Serialize, Deserialize, PartialEq, Eq, Clone, Copy)] +pub enum HashAlgo { + #[serde(rename = "sha256")] + Sha256, + #[serde(other)] + Unknown, +} + +impl Default for HashAlgo { + fn default() -> Self { + Self::Sha256 + } +} + +#[derive(Debug, Deserialize, PartialEq, Eq, Clone)] +pub struct BatchRequestObject { + pub oid: Oid, + pub size: i64, +} + +#[derive(Debug, Serialize, Deserialize, Clone)] +struct BatchRef { + name: String, +} + +fn default_transfers() -> Vec { + vec![TransferAdapter::Basic] +} + +#[derive(Debug, Deserialize, PartialEq, Eq, Clone)] +pub struct BatchRequest { + pub operation: Operation, + #[serde(default = "default_transfers")] + pub transfers: Vec, + pub objects: Vec, + #[serde(default)] + pub hash_algo: HashAlgo, +} + +#[derive(Debug, Clone)] +pub struct GitLfsJson(pub Json); + +pub const LFS_MIME: &str = "application/vnd.git-lfs+json"; + +pub enum GitLfsJsonRejection { + Json(rejection::JsonRejection), + MissingGitLfsJsonContentType, +} + +impl IntoResponse for GitLfsJsonRejection { + fn into_response(self) -> Response { + match self { + Self::Json(rej) => rej.into_response(), + Self::MissingGitLfsJsonContentType => make_error_resp( + StatusCode::UNSUPPORTED_MEDIA_TYPE, + &format!("Expected request with `Content-Type: {LFS_MIME}`"), + ) + .into_response(), + } + } +} + +pub fn is_git_lfs_json_mimetype(mimetype: &str) -> bool { + let Ok(mime) = mimetype.parse::() else { + return false; + }; + if mime.type_() != mime::APPLICATION + || mime.subtype() != "vnd.git-lfs" + || mime.suffix() != Some(mime::JSON) + { + return false; + } + match mime.get_param(mime::CHARSET) { + Some(mime::UTF_8) | None => true, + Some(_) => false, + } +} + +fn has_git_lfs_json_content_type(req: &Request) -> bool { + let Some(content_type) = req.headers().get(header::CONTENT_TYPE) else { + return false; + }; + let Ok(content_type) = content_type.to_str() else { + return false; + }; + is_git_lfs_json_mimetype(content_type) +} + +#[async_trait] +impl FromRequest for GitLfsJson +where + T: DeserializeOwned, + S: Send + Sync, +{ + type Rejection = GitLfsJsonRejection; + + async fn from_request(req: Request, state: &S) -> Result { + if !has_git_lfs_json_content_type(&req) { + return Err(GitLfsJsonRejection::MissingGitLfsJsonContentType); + } + Json::::from_request(req, state) + .await + .map(GitLfsJson) + .map_err(GitLfsJsonRejection::Json) + } +} + +impl IntoResponse for GitLfsJson { + fn into_response(self) -> Response { + let GitLfsJson(json) = self; + let mut resp = json.into_response(); + resp.headers_mut().insert( + header::CONTENT_TYPE, + HeaderValue::from_static("application/vnd.git-lfs+json; charset=utf-8"), + ); + resp + } +} + +#[derive(Debug, Serialize)] +pub struct GitLfsErrorData<'a> { + pub message: &'a str, +} + +pub type GitLfsErrorResponse<'a> = (StatusCode, GitLfsJson>); + +pub const fn make_error_resp(code: StatusCode, message: &str) -> GitLfsErrorResponse { + (code, GitLfsJson(Json(GitLfsErrorData { message }))) +} + +#[derive(Debug, Serialize, Clone)] +pub struct BatchResponseObjectAction { + pub href: String, + #[serde(skip_serializing_if = "HashMap::is_empty")] + pub header: HashMap, + pub expires_at: DateTime, +} + +#[derive(Default, Debug, Serialize, Clone)] +pub struct BatchResponseObjectActions { + #[serde(skip_serializing_if = "Option::is_none")] + pub upload: Option, + #[serde(skip_serializing_if = "Option::is_none")] + pub download: Option, + #[serde(skip_serializing_if = "Option::is_none")] + pub verify: Option, +} + +#[derive(Debug, Clone, Serialize)] +pub struct BatchResponseObjectError { + pub code: u16, + pub message: String, +} + +#[derive(Debug, Serialize, Clone)] +pub struct BatchResponseObject { + pub oid: Oid, + pub size: i64, + #[serde(skip_serializing_if = "Option::is_none")] + pub authenticated: Option, + pub actions: BatchResponseObjectActions, + #[serde(skip_serializing_if = "Option::is_none")] + pub error: Option, +} + +impl BatchResponseObject { + pub fn error( + obj: &BatchRequestObject, + code: StatusCode, + message: String, + ) -> BatchResponseObject { + BatchResponseObject { + oid: obj.oid, + size: obj.size, + authenticated: None, + actions: Default::default(), + error: Some(BatchResponseObjectError { + code: code.as_u16(), + message, + }), + } + } +} + +#[derive(Debug, Serialize, Clone)] +pub struct BatchResponse { + pub transfer: TransferAdapter, + pub objects: Vec, + pub hash_algo: HashAlgo, +} + +#[test] +fn test_mimetype() { + assert!(is_git_lfs_json_mimetype("application/vnd.git-lfs+json")); + assert!(!is_git_lfs_json_mimetype("application/vnd.git-lfs")); + assert!(!is_git_lfs_json_mimetype("application/json")); + assert!(is_git_lfs_json_mimetype( + "application/vnd.git-lfs+json; charset=utf-8" + )); + assert!(is_git_lfs_json_mimetype( + "application/vnd.git-lfs+json; charset=UTF-8" + )); + assert!(!is_git_lfs_json_mimetype( + "application/vnd.git-lfs+json; charset=ISO-8859-1" + )); +} + +#[test] +fn test_deserialize() { + let json = r#"{"operation":"upload","objects":[{"oid":"8f4123f9a7181f488c5e111d82cefd992e461ae5df01fd2254399e6e670b2d3c","size":170904}], + "transfers":["lfs-standalone-file","basic","ssh"],"ref":{"name":"refs/heads/main"},"hash_algo":"sha256"}"#; + let expected = BatchRequest { + operation: Operation::Upload, + objects: vec![BatchRequestObject { + oid: "8f4123f9a7181f488c5e111d82cefd992e461ae5df01fd2254399e6e670b2d3c" + .parse() + .unwrap(), + size: 170904, + }], + transfers: vec![ + TransferAdapter::Unknown, + TransferAdapter::Basic, + TransferAdapter::Unknown, + ], + hash_algo: HashAlgo::Sha256, + }; + assert_eq!( + serde_json::from_str::(json).unwrap(), + expected + ); +} diff --git a/gitolfs3-server/src/authz.rs b/gitolfs3-server/src/authz.rs new file mode 100644 index 0000000..0674cef --- /dev/null +++ b/gitolfs3-server/src/authz.rs @@ -0,0 +1,182 @@ +use std::collections::HashSet; + +use axum::http::{header, HeaderMap, StatusCode}; +use chrono::{DateTime, Utc}; +use gitolfs3_common::{generate_tag, Claims, Digest, Oid, Operation, SpecificClaims}; + +use crate::{ + api::{make_error_resp, GitLfsErrorResponse, REPO_NOT_FOUND}, + config::AuthorizationConfig, +}; + +pub struct Trusted(pub bool); + +fn forwarded_from_trusted_host( + headers: &HeaderMap, + trusted: &HashSet, +) -> Result> { + if let Some(forwarded_host) = headers.get("X-Forwarded-Host") { + if let Ok(forwarded_host) = forwarded_host.to_str() { + if trusted.contains(forwarded_host) { + return Ok(true); + } + } else { + return Err(make_error_resp( + StatusCode::NOT_FOUND, + "Invalid X-Forwarded-Host header", + )); + } + } + Ok(false) +} + +pub fn authorize_batch( + conf: &AuthorizationConfig, + repo_path: &str, + public: bool, + operation: Operation, + headers: &HeaderMap, +) -> Result> { + // - No authentication required for downloading exported repos + // - When authenticated: + // - Download / upload over presigned URLs + // - When accessing over Tailscale: + // - No authentication required for downloading from any repo + + let claims = VerifyClaimsInput { + specific_claims: SpecificClaims::BatchApi(operation), + repo_path, + }; + if !verify_claims(conf, &claims, headers)? { + return authorize_batch_unauthenticated(conf, public, operation, headers); + } + Ok(Trusted(true)) +} + +fn authorize_batch_unauthenticated( + conf: &AuthorizationConfig, + public: bool, + operation: Operation, + headers: &HeaderMap, +) -> Result> { + let trusted = forwarded_from_trusted_host(headers, &conf.trusted_forwarded_hosts)?; + match operation { + Operation::Upload => { + // Trusted users can clone all repositories (by virtue of accessing the server via a + // trusted network). However, they can not push without proper authentication. Untrusted + // users who are also not authenticated should not need to know which repositories exists. + // Therefore, we tell untrusted && unauthenticated users that the repo doesn't exist, but + // tell trusted users that they need to authenticate. + if !trusted { + return Err(REPO_NOT_FOUND); + } + Err(make_error_resp( + StatusCode::FORBIDDEN, + "Authentication required to upload", + )) + } + Operation::Download => { + // Again, trusted users can see all repos. For untrusted users, we first need to check + // whether the repo is public before we authorize. If the user is untrusted and the + // repo isn't public, we just act like it doesn't even exist. + if !trusted { + if !public { + return Err(REPO_NOT_FOUND); + } + return Ok(Trusted(false)); + } + Ok(Trusted(true)) + } + } +} + +pub fn authorize_get( + conf: &AuthorizationConfig, + repo_path: &str, + oid: Oid, + headers: &HeaderMap, +) -> Result<(), GitLfsErrorResponse<'static>> { + let claims = VerifyClaimsInput { + specific_claims: SpecificClaims::Download(oid), + repo_path, + }; + if !verify_claims(conf, &claims, headers)? { + return Err(make_error_resp( + StatusCode::UNAUTHORIZED, + "Repository not found", + )); + } + Ok(()) +} + +pub struct VerifyClaimsInput<'a> { + pub specific_claims: SpecificClaims, + pub repo_path: &'a str, +} + +fn verify_claims( + conf: &AuthorizationConfig, + claims: &VerifyClaimsInput, + headers: &HeaderMap, +) -> Result> { + const INVALID_AUTHZ_HEADER: GitLfsErrorResponse = + make_error_resp(StatusCode::BAD_REQUEST, "Invalid authorization header"); + + let Some(authz) = headers.get(header::AUTHORIZATION) else { + return Ok(false); + }; + let authz = authz.to_str().map_err(|_| INVALID_AUTHZ_HEADER)?; + let val = authz + .strip_prefix("Gitolfs3-Hmac-Sha256 ") + .ok_or(INVALID_AUTHZ_HEADER)?; + let (tag, expires_at) = val.split_once(' ').ok_or(INVALID_AUTHZ_HEADER)?; + let tag: Digest<32> = tag.parse().map_err(|_| INVALID_AUTHZ_HEADER)?; + let expires_at: i64 = expires_at.parse().map_err(|_| INVALID_AUTHZ_HEADER)?; + let expires_at = DateTime::::from_timestamp(expires_at, 0).ok_or(INVALID_AUTHZ_HEADER)?; + let expected_tag = generate_tag( + Claims { + specific_claims: claims.specific_claims, + repo_path: claims.repo_path, + expires_at, + }, + &conf.key, + ) + .ok_or_else(|| make_error_resp(StatusCode::INTERNAL_SERVER_ERROR, "Internal server error"))?; + if tag != expected_tag { + return Err(INVALID_AUTHZ_HEADER); + } + + Ok(true) +} + +#[test] +fn test_validate_claims() { + use gitolfs3_common::Key; + + let key = "00232f7a019bd34e3921ee6c5f04caf48a4489d1be5d1999038950a7054e0bfea369ce2becc0f13fd3c69f8af2384a25b7ac2d52eb52c33722f3c00c50d4c9c2"; + let key: Key = key.parse().unwrap(); + + let claims = Claims { + expires_at: Utc::now() + std::time::Duration::from_secs(5 * 60), + repo_path: "lfs-test.git", + specific_claims: SpecificClaims::BatchApi(Operation::Download), + }; + let tag = generate_tag(claims, &key).unwrap(); + let header_value = format!( + "Gitolfs3-Hmac-Sha256 {tag} {}", + claims.expires_at.timestamp() + ); + + let conf = AuthorizationConfig { + key, + trusted_forwarded_hosts: HashSet::new(), + }; + let verification_claims = VerifyClaimsInput { + repo_path: claims.repo_path, + specific_claims: claims.specific_claims, + }; + let mut headers = HeaderMap::new(); + headers.insert(header::AUTHORIZATION, header_value.try_into().unwrap()); + + assert!(verify_claims(&conf, &verification_claims, &headers).unwrap()); +} diff --git a/gitolfs3-server/src/config.rs b/gitolfs3-server/src/config.rs new file mode 100644 index 0000000..75e84dc --- /dev/null +++ b/gitolfs3-server/src/config.rs @@ -0,0 +1,122 @@ +use std::collections::HashSet; + +use gitolfs3_common::{load_key, Key}; + +struct Env { + s3_access_key_id: String, + s3_secret_access_key: String, + s3_bucket: String, + s3_region: String, + s3_endpoint: String, + base_url: String, + key_path: String, + listen_host: String, + listen_port: String, + download_limit: String, + trusted_forwarded_hosts: String, +} + +fn require_env(name: &str) -> Result { + std::env::var(name) + .map_err(|_| format!("environment variable {name} should be defined and valid")) +} + +impl Env { + fn load() -> Result { + Ok(Env { + s3_secret_access_key: require_env("GITOLFS3_S3_SECRET_ACCESS_KEY_FILE")?, + s3_access_key_id: require_env("GITOLFS3_S3_ACCESS_KEY_ID_FILE")?, + s3_region: require_env("GITOLFS3_S3_REGION")?, + s3_endpoint: require_env("GITOLFS3_S3_ENDPOINT")?, + s3_bucket: require_env("GITOLFS3_S3_BUCKET")?, + base_url: require_env("GITOLFS3_BASE_URL")?, + key_path: require_env("GITOLFS3_KEY_PATH")?, + listen_host: require_env("GITOLFS3_LISTEN_HOST")?, + listen_port: require_env("GITOLFS3_LISTEN_PORT")?, + download_limit: require_env("GITOLFS3_DOWNLOAD_LIMIT")?, + trusted_forwarded_hosts: std::env::var("GITOLFS3_TRUSTED_FORWARDED_HOSTS") + .unwrap_or_default(), + }) + } +} + +fn get_s3_client(env: &Env) -> Result { + let access_key_id = std::fs::read_to_string(&env.s3_access_key_id)?; + let secret_access_key = std::fs::read_to_string(&env.s3_secret_access_key)?; + + let credentials = aws_sdk_s3::config::Credentials::new( + access_key_id, + secret_access_key, + None, + None, + "gitolfs3-env", + ); + let config = aws_config::SdkConfig::builder() + .behavior_version(aws_config::BehaviorVersion::latest()) + .region(aws_config::Region::new(env.s3_region.clone())) + .endpoint_url(&env.s3_endpoint) + .credentials_provider(aws_sdk_s3::config::SharedCredentialsProvider::new( + credentials, + )) + .build(); + Ok(aws_sdk_s3::Client::new(&config)) +} + +pub struct Config { + pub listen_addr: (String, u16), + pub base_url: String, + pub authz_conf: AuthorizationConfig, + pub s3_client: aws_sdk_s3::Client, + pub s3_bucket: String, + pub download_limit: u64, +} + +pub struct AuthorizationConfig { + pub trusted_forwarded_hosts: HashSet, + pub key: Key, +} + +impl Config { + pub fn load() -> Result { + let env = match Env::load() { + Ok(env) => env, + Err(e) => return Err(format!("failed to load configuration: {e}")), + }; + + let s3_client = match get_s3_client(&env) { + Ok(s3_client) => s3_client, + Err(e) => return Err(format!("failed to create S3 client: {e}")), + }; + let key = match load_key(&env.key_path) { + Ok(key) => key, + Err(e) => return Err(format!("failed to load Gitolfs3 key: {e}")), + }; + + let trusted_forwarded_hosts: HashSet = env + .trusted_forwarded_hosts + .split(',') + .map(|s| s.to_owned()) + .filter(|s| !s.is_empty()) + .collect(); + let base_url = env.base_url.trim_end_matches('/').to_string(); + + let Ok(listen_port): Result = env.listen_port.parse() else { + return Err("configured GITOLFS3_LISTEN_PORT is invalid".to_string()); + }; + let Ok(download_limit): Result = env.download_limit.parse() else { + return Err("configured GITOLFS3_DOWNLOAD_LIMIT is invalid".to_string()); + }; + + Ok(Self { + listen_addr: (env.listen_host, listen_port), + base_url, + authz_conf: AuthorizationConfig { + key, + trusted_forwarded_hosts, + }, + s3_client, + s3_bucket: env.s3_bucket, + download_limit, + }) + } +} diff --git a/gitolfs3-server/src/dlimit.rs b/gitolfs3-server/src/dlimit.rs new file mode 100644 index 0000000..f68bec1 --- /dev/null +++ b/gitolfs3-server/src/dlimit.rs @@ -0,0 +1,73 @@ +use std::sync::Arc; +use std::time::Duration; +use tokio::io::AsyncWriteExt; +use tokio::sync::Mutex; + +// I know that this is pretty bad, but it's good enough (??) for now. +pub struct DownloadLimiter { + current: u64, + limit: u64, +} + +impl DownloadLimiter { + pub async fn new(limit: u64) -> Arc> { + let dlimit_str = match tokio::fs::read_to_string(".gitolfs3-dlimit").await { + Ok(dlimit_str) => dlimit_str, + Err(e) => { + println!("Failed to read download counter, assuming 0: {e}"); + return DownloadLimiter { current: 0, limit }.auto_resetting(); + } + }; + let current: u64 = match dlimit_str + .parse() + .map_err(|e| tokio::io::Error::new(tokio::io::ErrorKind::InvalidData, e)) + { + Ok(current) => current, + Err(e) => { + println!("Failed to read download counter, assuming 0: {e}"); + return DownloadLimiter { current: 0, limit }.auto_resetting(); + } + }; + + DownloadLimiter { current, limit }.auto_resetting() + } + + fn auto_resetting(self) -> Arc> { + let limiter_ref = Arc::new(Mutex::new(self)); + let limiter_ref_cloned = limiter_ref.clone(); + tokio::spawn(async move { + loop { + println!("Resetting download counter in one hour"); + tokio::time::sleep(Duration::from_secs(3600)).await; + println!("Resetting download counter"); + limiter_ref_cloned.lock().await.reset().await; + } + }); + limiter_ref + } + + pub async fn request(&mut self, n: u64) -> tokio::io::Result { + if self.current + n > self.limit { + return Ok(false); + } + self.current += n; + self.write_new_count().await?; + Ok(true) + } + + pub async fn reset(&mut self) { + self.current = 0; + if let Err(e) = self.write_new_count().await { + println!("Failed to reset download counter: {e}"); + } + } + + async fn write_new_count(&self) -> tokio::io::Result<()> { + let cwd = tokio::fs::File::open(std::env::current_dir()?).await?; + let mut file = tokio::fs::File::create(".gitolfs3-dlimit.tmp").await?; + file.write_all(self.current.to_string().as_bytes()).await?; + file.sync_all().await?; + tokio::fs::rename(".gitolfs3-dlimit.tmp", ".gitolfs3-dlimit").await?; + cwd.sync_all().await + } +} diff --git a/gitolfs3-server/src/handler.rs b/gitolfs3-server/src/handler.rs new file mode 100644 index 0000000..6516291 --- /dev/null +++ b/gitolfs3-server/src/handler.rs @@ -0,0 +1,455 @@ +use std::{collections::HashMap, sync::Arc}; + +use aws_sdk_s3::{error::SdkError, operation::head_object::HeadObjectOutput}; +use axum::{ + extract::{Path, State}, + http::{header, HeaderMap, StatusCode}, + response::{IntoResponse, Response}, + Json, +}; +use base64::{prelude::BASE64_STANDARD, Engine}; +use chrono::Utc; +use gitolfs3_common::{generate_tag, Claims, HexByte, Oid, Operation, SpecificClaims}; +use serde::{de, Deserialize}; +use tokio::sync::Mutex; + +use crate::{ + api::{ + is_git_lfs_json_mimetype, make_error_resp, BatchRequest, BatchRequestObject, BatchResponse, + BatchResponseObject, BatchResponseObjectAction, BatchResponseObjectActions, GitLfsJson, + HashAlgo, RepositoryName, TransferAdapter, LFS_MIME, REPO_NOT_FOUND, + }, + authz::{authorize_batch, authorize_get, Trusted}, + config::AuthorizationConfig, + dlimit::DownloadLimiter, +}; + +pub struct AppState { + pub s3_client: aws_sdk_s3::Client, + pub s3_bucket: String, + pub authz_conf: AuthorizationConfig, + // Should not end with a slash. + pub base_url: String, + pub dl_limiter: Arc>, +} + +fn validate_checksum(oid: Oid, obj: &HeadObjectOutput) -> bool { + if let Some(checksum) = obj.checksum_sha256() { + if let Ok(checksum) = BASE64_STANDARD.decode(checksum) { + if let Ok(checksum32b) = TryInto::<[u8; 32]>::try_into(checksum) { + return Oid::from(checksum32b) == oid; + } + } + } + true +} + +fn validate_size(expected: i64, obj: &HeadObjectOutput) -> bool { + if let Some(length) = obj.content_length() { + return length == expected; + } + true +} + +async fn handle_upload_object( + state: &AppState, + repo: &str, + obj: &BatchRequestObject, +) -> Option { + let (oid0, oid1) = (HexByte(obj.oid[0]), HexByte(obj.oid[1])); + let full_path = format!("{repo}/lfs/objects/{}/{}/{}", oid0, oid1, obj.oid); + + match state + .s3_client + .head_object() + .bucket(&state.s3_bucket) + .key(full_path.clone()) + .checksum_mode(aws_sdk_s3::types::ChecksumMode::Enabled) + .send() + .await + { + Ok(result) => { + if validate_size(obj.size, &result) && validate_checksum(obj.oid, &result) { + return None; + } + } + Err(SdkError::ServiceError(e)) if e.err().is_not_found() => {} + Err(e) => { + println!("Failed to HeadObject (repo {repo}, OID {}): {e}", obj.oid); + return Some(BatchResponseObject::error( + obj, + StatusCode::INTERNAL_SERVER_ERROR, + "Failed to query object information".to_string(), + )); + } + }; + + let expires_in = std::time::Duration::from_secs(5 * 60); + let expires_at = Utc::now() + expires_in; + + let Ok(config) = aws_sdk_s3::presigning::PresigningConfig::expires_in(expires_in) else { + return Some(BatchResponseObject::error( + obj, + StatusCode::INTERNAL_SERVER_ERROR, + "Failed to generate upload URL".to_string(), + )); + }; + let Ok(presigned) = state + .s3_client + .put_object() + .bucket(&state.s3_bucket) + .key(full_path) + .checksum_sha256(obj.oid.to_string()) + .content_length(obj.size) + .presigned(config) + .await + else { + return Some(BatchResponseObject::error( + obj, + StatusCode::INTERNAL_SERVER_ERROR, + "Failed to generate upload URL".to_string(), + )); + }; + Some(BatchResponseObject { + oid: obj.oid, + size: obj.size, + authenticated: Some(true), + actions: BatchResponseObjectActions { + upload: Some(BatchResponseObjectAction { + header: presigned + .headers() + .map(|(k, v)| (k.to_owned(), v.to_owned())) + .collect(), + expires_at, + href: presigned.uri().to_string(), + }), + ..Default::default() + }, + error: None, + }) +} + +async fn handle_download_object( + state: &AppState, + repo: &str, + obj: &BatchRequestObject, + trusted: bool, +) -> BatchResponseObject { + let (oid0, oid1) = (HexByte(obj.oid[0]), HexByte(obj.oid[1])); + let full_path = format!("{repo}/lfs/objects/{}/{}/{}", oid0, oid1, obj.oid); + + let result = match state + .s3_client + .head_object() + .bucket(&state.s3_bucket) + .key(&full_path) + .checksum_mode(aws_sdk_s3::types::ChecksumMode::Enabled) + .send() + .await + { + Ok(result) => result, + Err(e) => { + println!("Failed to HeadObject (repo {repo}, OID {}): {e}", obj.oid); + return BatchResponseObject::error( + obj, + StatusCode::INTERNAL_SERVER_ERROR, + "Failed to query object information".to_string(), + ); + } + }; + + // Scaleway actually doesn't provide SHA256 suport, but maybe in the future :) + if !validate_checksum(obj.oid, &result) { + return BatchResponseObject::error( + obj, + StatusCode::UNPROCESSABLE_ENTITY, + "Object corrupted".to_string(), + ); + } + if !validate_size(obj.size, &result) { + return BatchResponseObject::error( + obj, + StatusCode::UNPROCESSABLE_ENTITY, + "Incorrect size specified (or object corrupted)".to_string(), + ); + } + + let expires_in = std::time::Duration::from_secs(5 * 60); + let expires_at = Utc::now() + expires_in; + + if trusted { + let Ok(config) = aws_sdk_s3::presigning::PresigningConfig::expires_in(expires_in) else { + return BatchResponseObject::error( + obj, + StatusCode::INTERNAL_SERVER_ERROR, + "Failed to generate upload URL".to_string(), + ); + }; + let Ok(presigned) = state + .s3_client + .get_object() + .bucket(&state.s3_bucket) + .key(full_path) + .presigned(config) + .await + else { + return BatchResponseObject::error( + obj, + StatusCode::INTERNAL_SERVER_ERROR, + "Failed to generate upload URL".to_string(), + ); + }; + return BatchResponseObject { + oid: obj.oid, + size: obj.size, + authenticated: Some(true), + actions: BatchResponseObjectActions { + download: Some(BatchResponseObjectAction { + header: presigned + .headers() + .map(|(k, v)| (k.to_owned(), v.to_owned())) + .collect(), + expires_at, + href: presigned.uri().to_string(), + }), + ..Default::default() + }, + error: None, + }; + } + + if let Some(content_length) = result.content_length() { + if content_length > 0 { + match state + .dl_limiter + .lock() + .await + .request(content_length as u64) + .await + { + Ok(true) => {} + Ok(false) => { + return BatchResponseObject::error( + obj, + StatusCode::SERVICE_UNAVAILABLE, + "Public LFS downloads temporarily unavailable".to_string(), + ); + } + Err(e) => { + println!("Failed to request {content_length} bytes from download limiter: {e}"); + return BatchResponseObject::error( + obj, + StatusCode::INTERNAL_SERVER_ERROR, + "Internal server error".to_string(), + ); + } + } + } + } + + let Some(tag) = generate_tag( + Claims { + specific_claims: SpecificClaims::Download(obj.oid), + repo_path: repo, + expires_at, + }, + &state.authz_conf.key, + ) else { + return BatchResponseObject::error( + obj, + StatusCode::INTERNAL_SERVER_ERROR, + "Internal server error".to_string(), + ); + }; + + let upload_path = format!( + "{repo}/info/lfs/objects/{}/{}/{}", + HexByte(obj.oid[0]), + HexByte(obj.oid[1]), + obj.oid, + ); + + BatchResponseObject { + oid: obj.oid, + size: obj.size, + authenticated: Some(true), + actions: BatchResponseObjectActions { + download: Some(BatchResponseObjectAction { + header: { + let mut map = HashMap::new(); + map.insert( + "Authorization".to_string(), + format!("Gitolfs3-Hmac-Sha256 {tag} {}", expires_at.timestamp()), + ); + map + }, + expires_at, + href: format!("{}/{upload_path}", state.base_url), + }), + ..Default::default() + }, + error: None, + } +} + +fn repo_exists(name: &str) -> bool { + let Ok(metadata) = std::fs::metadata(name) else { + return false; + }; + metadata.is_dir() +} + +fn is_repo_public(name: &str) -> Option { + if !repo_exists(name) { + return None; + } + match std::fs::metadata(format!("{name}/git-daemon-export-ok")) { + Ok(metadata) if metadata.is_file() => Some(true), + Err(e) if e.kind() == std::io::ErrorKind::NotFound => Some(false), + _ => None, + } +} + +pub async fn batch( + State(state): State>, + headers: HeaderMap, + RepositoryName(repo): RepositoryName, + GitLfsJson(Json(payload)): GitLfsJson, +) -> Response { + let Some(public) = is_repo_public(&repo) else { + return REPO_NOT_FOUND.into_response(); + }; + let Trusted(trusted) = match authorize_batch( + &state.authz_conf, + &repo, + public, + payload.operation, + &headers, + ) { + Ok(authn) => authn, + Err(e) => return e.into_response(), + }; + + if !headers + .get_all("Accept") + .iter() + .filter_map(|v| v.to_str().ok()) + .any(is_git_lfs_json_mimetype) + { + let message = format!("Expected `{LFS_MIME}` in list of acceptable response media types"); + return make_error_resp(StatusCode::NOT_ACCEPTABLE, &message).into_response(); + } + + if payload.hash_algo != HashAlgo::Sha256 { + let message = "Unsupported hashing algorithm specified"; + return make_error_resp(StatusCode::CONFLICT, message).into_response(); + } + if !payload.transfers.is_empty() && !payload.transfers.contains(&TransferAdapter::Basic) { + let message = "Unsupported transfer adapter specified (supported: basic)"; + return make_error_resp(StatusCode::CONFLICT, message).into_response(); + } + + let mut resp = BatchResponse { + transfer: TransferAdapter::Basic, + objects: vec![], + hash_algo: HashAlgo::Sha256, + }; + for obj in payload.objects { + match payload.operation { + Operation::Download => resp + .objects + .push(handle_download_object(&state, &repo, &obj, trusted).await), + Operation::Upload => { + if let Some(obj_resp) = handle_upload_object(&state, &repo, &obj).await { + resp.objects.push(obj_resp); + } + } + }; + } + GitLfsJson(Json(resp)).into_response() +} + +#[derive(Deserialize, Copy, Clone)] +#[serde(remote = "Self")] +pub struct FileParams { + oid0: HexByte, + oid1: HexByte, + oid: Oid, +} + +impl<'de> Deserialize<'de> for FileParams { + fn deserialize(deserializer: D) -> Result + where + D: serde::Deserializer<'de>, + { + let unchecked @ FileParams { + oid0: HexByte(oid0), + oid1: HexByte(oid1), + oid, + } = FileParams::deserialize(deserializer)?; + if oid0 != oid.as_bytes()[0] { + return Err(de::Error::custom( + "first OID path part does not match first byte of full OID", + )); + } + if oid1 != oid.as_bytes()[1] { + return Err(de::Error::custom( + "second OID path part does not match first byte of full OID", + )); + } + Ok(unchecked) + } +} + +pub async fn obj_download( + State(state): State>, + headers: HeaderMap, + RepositoryName(repo): RepositoryName, + Path(FileParams { oid0, oid1, oid }): Path, +) -> Response { + if let Err(e) = authorize_get(&state.authz_conf, &repo, oid, &headers) { + return e.into_response(); + } + + let full_path = format!("{repo}/lfs/objects/{}/{}/{}", oid0, oid1, oid); + let result = match state + .s3_client + .get_object() + .bucket(&state.s3_bucket) + .key(full_path) + .checksum_mode(aws_sdk_s3::types::ChecksumMode::Enabled) + .send() + .await + { + Ok(result) => result, + Err(e) => { + println!("Failed to GetObject (repo {repo}, OID {oid}): {e}"); + return ( + StatusCode::INTERNAL_SERVER_ERROR, + "Failed to query object information", + ) + .into_response(); + } + }; + + let mut headers = header::HeaderMap::new(); + if let Some(content_type) = result.content_type { + let Ok(header_value) = content_type.try_into() else { + return ( + StatusCode::INTERNAL_SERVER_ERROR, + "Object has invalid content type", + ) + .into_response(); + }; + headers.insert(header::CONTENT_TYPE, header_value); + } + if let Some(content_length) = result.content_length { + headers.insert(header::CONTENT_LENGTH, content_length.into()); + } + + let async_read = result.body.into_async_read(); + let stream = tokio_util::io::ReaderStream::new(async_read); + let body = axum::body::Body::from_stream(stream); + + (headers, body).into_response() +} diff --git a/gitolfs3-server/src/main.rs b/gitolfs3-server/src/main.rs index b05a0c8..c9911ed 100644 --- a/gitolfs3-server/src/main.rs +++ b/gitolfs3-server/src/main.rs @@ -1,27 +1,21 @@ -use aws_sdk_s3::{error::SdkError, operation::head_object::HeadObjectOutput}; +mod api; +mod authz; +mod config; +mod dlimit; +mod handler; + +use api::RepositoryName; +use config::Config; +use dlimit::DownloadLimiter; + use axum::{ - async_trait, - extract::{rejection, FromRequest, FromRequestParts, OriginalUri, Path, Request, State}, - http::{header, request::Parts, HeaderMap, HeaderValue, StatusCode, Uri}, - response::{IntoResponse, Response}, + extract::OriginalUri, + http::{StatusCode, Uri}, routing::{get, post}, - Extension, Json, Router, ServiceExt, -}; -use base64::prelude::*; -use chrono::{DateTime, Utc}; -use gitolfs3_common::{ - generate_tag, load_key, Claims, Digest, HexByte, Key, Oid, Operation, SpecificClaims, -}; -use serde::{ - de::{self, DeserializeOwned}, - Deserialize, Serialize, + Router, ServiceExt, }; -use std::{ - collections::{HashMap, HashSet}, - process::ExitCode, - sync::Arc, -}; -use tokio::io::AsyncWriteExt; +use handler::AppState; +use std::{process::ExitCode, sync::Arc}; use tower::Layer; #[tokio::main] @@ -37,18 +31,6 @@ async fn main() -> ExitCode { }; let dl_limiter = DownloadLimiter::new(conf.download_limit).await; - let dl_limiter = Arc::new(tokio::sync::Mutex::new(dl_limiter)); - - let resetter_dl_limiter = dl_limiter.clone(); - tokio::spawn(async move { - loop { - println!("Resetting download counter in one hour"); - tokio::time::sleep(std::time::Duration::from_secs(3600)).await; - println!("Resetting download counter"); - resetter_dl_limiter.lock().await.reset().await; - } - }); - let shared_state = Arc::new(AppState { s3_client: conf.s3_client, s3_bucket: conf.s3_bucket, @@ -57,8 +39,8 @@ async fn main() -> ExitCode { dl_limiter, }); let app = Router::new() - .route("/batch", post(batch)) - .route("/:oid0/:oid1/:oid", get(obj_download)) + .route("/batch", post(handler::batch)) + .route("/:oid0/:oid1/:oid", get(handler::obj_download)) .with_state(shared_state); let middleware = axum::middleware::map_request(rewrite_url); @@ -81,30 +63,6 @@ async fn main() -> ExitCode { } } -#[derive(Clone)] -struct RepositoryName(String); - -struct RepositoryNameRejection; - -impl IntoResponse for RepositoryNameRejection { - fn into_response(self) -> Response { - (StatusCode::INTERNAL_SERVER_ERROR, "Missing repository name").into_response() - } -} - -#[async_trait] -impl FromRequestParts for RepositoryName { - type Rejection = RepositoryNameRejection; - - async fn from_request_parts(parts: &mut Parts, state: &S) -> Result { - let Ok(Extension(repo_name)) = Extension::::from_request_parts(parts, state).await - else { - return Err(RepositoryNameRejection); - }; - Ok(repo_name) - } -} - async fn rewrite_url( mut req: axum::http::Request, ) -> Result, StatusCode> { @@ -141,1014 +99,3 @@ async fn rewrite_url( Ok(req) } - -struct AppState { - s3_client: aws_sdk_s3::Client, - s3_bucket: String, - authz_conf: AuthorizationConfig, - // Should not end with a slash. - base_url: String, - dl_limiter: Arc>, -} - -struct Env { - s3_access_key_id: String, - s3_secret_access_key: String, - s3_bucket: String, - s3_region: String, - s3_endpoint: String, - base_url: String, - key_path: String, - listen_host: String, - listen_port: String, - download_limit: String, - trusted_forwarded_hosts: String, -} - -fn require_env(name: &str) -> Result { - std::env::var(name) - .map_err(|_| format!("environment variable {name} should be defined and valid")) -} - -impl Env { - fn load() -> Result { - Ok(Env { - s3_secret_access_key: require_env("GITOLFS3_S3_SECRET_ACCESS_KEY_FILE")?, - s3_access_key_id: require_env("GITOLFS3_S3_ACCESS_KEY_ID_FILE")?, - s3_region: require_env("GITOLFS3_S3_REGION")?, - s3_endpoint: require_env("GITOLFS3_S3_ENDPOINT")?, - s3_bucket: require_env("GITOLFS3_S3_BUCKET")?, - base_url: require_env("GITOLFS3_BASE_URL")?, - key_path: require_env("GITOLFS3_KEY_PATH")?, - listen_host: require_env("GITOLFS3_LISTEN_HOST")?, - listen_port: require_env("GITOLFS3_LISTEN_PORT")?, - download_limit: require_env("GITOLFS3_DOWNLOAD_LIMIT")?, - trusted_forwarded_hosts: std::env::var("GITOLFS3_TRUSTED_FORWARDED_HOSTS") - .unwrap_or_default(), - }) - } -} - -fn get_s3_client(env: &Env) -> Result { - let access_key_id = std::fs::read_to_string(&env.s3_access_key_id)?; - let secret_access_key = std::fs::read_to_string(&env.s3_secret_access_key)?; - - let credentials = aws_sdk_s3::config::Credentials::new( - access_key_id, - secret_access_key, - None, - None, - "gitolfs3-env", - ); - let config = aws_config::SdkConfig::builder() - .behavior_version(aws_config::BehaviorVersion::latest()) - .region(aws_config::Region::new(env.s3_region.clone())) - .endpoint_url(&env.s3_endpoint) - .credentials_provider(aws_sdk_s3::config::SharedCredentialsProvider::new( - credentials, - )) - .build(); - Ok(aws_sdk_s3::Client::new(&config)) -} - -struct Config { - listen_addr: (String, u16), - base_url: String, - authz_conf: AuthorizationConfig, - s3_client: aws_sdk_s3::Client, - s3_bucket: String, - download_limit: u64, -} - -impl Config { - fn load() -> Result { - let env = match Env::load() { - Ok(env) => env, - Err(e) => return Err(format!("failed to load configuration: {e}")), - }; - - let s3_client = match get_s3_client(&env) { - Ok(s3_client) => s3_client, - Err(e) => return Err(format!("failed to create S3 client: {e}")), - }; - let key = match load_key(&env.key_path) { - Ok(key) => key, - Err(e) => return Err(format!("failed to load Gitolfs3 key: {e}")), - }; - - let trusted_forwarded_hosts: HashSet = env - .trusted_forwarded_hosts - .split(',') - .map(|s| s.to_owned()) - .filter(|s| !s.is_empty()) - .collect(); - let base_url = env.base_url.trim_end_matches('/').to_string(); - - let Ok(listen_port): Result = env.listen_port.parse() else { - return Err("configured GITOLFS3_LISTEN_PORT is invalid".to_string()); - }; - let Ok(download_limit): Result = env.download_limit.parse() else { - return Err("configured GITOLFS3_DOWNLOAD_LIMIT is invalid".to_string()); - }; - - Ok(Self { - listen_addr: (env.listen_host, listen_port), - base_url, - authz_conf: AuthorizationConfig { - key, - trusted_forwarded_hosts, - }, - s3_client, - s3_bucket: env.s3_bucket, - download_limit, - }) - } -} - -#[derive(Debug, Serialize, Deserialize, PartialEq, Eq, Clone, Copy)] -enum TransferAdapter { - #[serde(rename = "basic")] - Basic, - #[serde(other)] - Unknown, -} - -#[derive(Debug, Serialize, Deserialize, PartialEq, Eq, Clone, Copy)] -enum HashAlgo { - #[serde(rename = "sha256")] - Sha256, - #[serde(other)] - Unknown, -} - -impl Default for HashAlgo { - fn default() -> Self { - Self::Sha256 - } -} - -#[derive(Debug, Deserialize, PartialEq, Eq, Clone)] -struct BatchRequestObject { - oid: Oid, - size: i64, -} - -#[derive(Debug, Serialize, Deserialize, Clone)] -struct BatchRef { - name: String, -} - -fn default_transfers() -> Vec { - vec![TransferAdapter::Basic] -} - -#[derive(Debug, Deserialize, PartialEq, Eq, Clone)] -struct BatchRequest { - operation: Operation, - #[serde(default = "default_transfers")] - transfers: Vec, - objects: Vec, - #[serde(default)] - hash_algo: HashAlgo, -} - -#[derive(Debug, Clone)] -struct GitLfsJson(Json); - -const LFS_MIME: &str = "application/vnd.git-lfs+json"; - -enum GitLfsJsonRejection { - Json(rejection::JsonRejection), - MissingGitLfsJsonContentType, -} - -impl IntoResponse for GitLfsJsonRejection { - fn into_response(self) -> Response { - match self { - Self::Json(rej) => rej.into_response(), - Self::MissingGitLfsJsonContentType => make_error_resp( - StatusCode::UNSUPPORTED_MEDIA_TYPE, - &format!("Expected request with `Content-Type: {LFS_MIME}`"), - ) - .into_response(), - } - } -} - -fn is_git_lfs_json_mimetype(mimetype: &str) -> bool { - let Ok(mime) = mimetype.parse::() else { - return false; - }; - if mime.type_() != mime::APPLICATION - || mime.subtype() != "vnd.git-lfs" - || mime.suffix() != Some(mime::JSON) - { - return false; - } - match mime.get_param(mime::CHARSET) { - Some(mime::UTF_8) | None => true, - Some(_) => false, - } -} - -fn has_git_lfs_json_content_type(req: &Request) -> bool { - let Some(content_type) = req.headers().get(header::CONTENT_TYPE) else { - return false; - }; - let Ok(content_type) = content_type.to_str() else { - return false; - }; - is_git_lfs_json_mimetype(content_type) -} - -#[async_trait] -impl FromRequest for GitLfsJson -where - T: DeserializeOwned, - S: Send + Sync, -{ - type Rejection = GitLfsJsonRejection; - - async fn from_request(req: Request, state: &S) -> Result { - if !has_git_lfs_json_content_type(&req) { - return Err(GitLfsJsonRejection::MissingGitLfsJsonContentType); - } - Json::::from_request(req, state) - .await - .map(GitLfsJson) - .map_err(GitLfsJsonRejection::Json) - } -} - -impl IntoResponse for GitLfsJson { - fn into_response(self) -> Response { - let GitLfsJson(json) = self; - let mut resp = json.into_response(); - resp.headers_mut().insert( - header::CONTENT_TYPE, - HeaderValue::from_static("application/vnd.git-lfs+json; charset=utf-8"), - ); - resp - } -} - -#[derive(Debug, Serialize)] -struct GitLfsErrorData<'a> { - message: &'a str, -} - -type GitLfsErrorResponse<'a> = (StatusCode, GitLfsJson>); - -const fn make_error_resp(code: StatusCode, message: &str) -> GitLfsErrorResponse { - (code, GitLfsJson(Json(GitLfsErrorData { message }))) -} - -#[derive(Debug, Serialize, Clone)] -struct BatchResponseObjectAction { - href: String, - #[serde(skip_serializing_if = "HashMap::is_empty")] - header: HashMap, - expires_at: DateTime, -} - -#[derive(Default, Debug, Serialize, Clone)] -struct BatchResponseObjectActions { - #[serde(skip_serializing_if = "Option::is_none")] - upload: Option, - #[serde(skip_serializing_if = "Option::is_none")] - download: Option, - #[serde(skip_serializing_if = "Option::is_none")] - verify: Option, -} - -#[derive(Debug, Clone, Serialize)] -struct BatchResponseObjectError { - code: u16, - message: String, -} - -#[derive(Debug, Serialize, Clone)] -struct BatchResponseObject { - oid: Oid, - size: i64, - #[serde(skip_serializing_if = "Option::is_none")] - authenticated: Option, - actions: BatchResponseObjectActions, - #[serde(skip_serializing_if = "Option::is_none")] - error: Option, -} - -impl BatchResponseObject { - fn error(obj: &BatchRequestObject, code: StatusCode, message: String) -> BatchResponseObject { - BatchResponseObject { - oid: obj.oid, - size: obj.size, - authenticated: None, - actions: Default::default(), - error: Some(BatchResponseObjectError { - code: code.as_u16(), - message, - }), - } - } -} - -#[derive(Debug, Serialize, Clone)] -struct BatchResponse { - transfer: TransferAdapter, - objects: Vec, - hash_algo: HashAlgo, -} - -fn validate_checksum(oid: Oid, obj: &HeadObjectOutput) -> bool { - if let Some(checksum) = obj.checksum_sha256() { - if let Ok(checksum) = BASE64_STANDARD.decode(checksum) { - if let Ok(checksum32b) = TryInto::<[u8; 32]>::try_into(checksum) { - return Oid::from(checksum32b) == oid; - } - } - } - true -} - -fn validate_size(expected: i64, obj: &HeadObjectOutput) -> bool { - if let Some(length) = obj.content_length() { - return length == expected; - } - true -} - -async fn handle_upload_object( - state: &AppState, - repo: &str, - obj: &BatchRequestObject, -) -> Option { - let (oid0, oid1) = (HexByte(obj.oid[0]), HexByte(obj.oid[1])); - let full_path = format!("{repo}/lfs/objects/{}/{}/{}", oid0, oid1, obj.oid); - - match state - .s3_client - .head_object() - .bucket(&state.s3_bucket) - .key(full_path.clone()) - .checksum_mode(aws_sdk_s3::types::ChecksumMode::Enabled) - .send() - .await - { - Ok(result) => { - if validate_size(obj.size, &result) && validate_checksum(obj.oid, &result) { - return None; - } - } - Err(SdkError::ServiceError(e)) if e.err().is_not_found() => {} - Err(e) => { - println!("Failed to HeadObject (repo {repo}, OID {}): {e}", obj.oid); - return Some(BatchResponseObject::error( - obj, - StatusCode::INTERNAL_SERVER_ERROR, - "Failed to query object information".to_string(), - )); - } - }; - - let expires_in = std::time::Duration::from_secs(5 * 60); - let expires_at = Utc::now() + expires_in; - - let Ok(config) = aws_sdk_s3::presigning::PresigningConfig::expires_in(expires_in) else { - return Some(BatchResponseObject::error( - obj, - StatusCode::INTERNAL_SERVER_ERROR, - "Failed to generate upload URL".to_string(), - )); - }; - let Ok(presigned) = state - .s3_client - .put_object() - .bucket(&state.s3_bucket) - .key(full_path) - .checksum_sha256(obj.oid.to_string()) - .content_length(obj.size) - .presigned(config) - .await - else { - return Some(BatchResponseObject::error( - obj, - StatusCode::INTERNAL_SERVER_ERROR, - "Failed to generate upload URL".to_string(), - )); - }; - Some(BatchResponseObject { - oid: obj.oid, - size: obj.size, - authenticated: Some(true), - actions: BatchResponseObjectActions { - upload: Some(BatchResponseObjectAction { - header: presigned - .headers() - .map(|(k, v)| (k.to_owned(), v.to_owned())) - .collect(), - expires_at, - href: presigned.uri().to_string(), - }), - ..Default::default() - }, - error: None, - }) -} - -async fn handle_download_object( - state: &AppState, - repo: &str, - obj: &BatchRequestObject, - trusted: bool, -) -> BatchResponseObject { - let (oid0, oid1) = (HexByte(obj.oid[0]), HexByte(obj.oid[1])); - let full_path = format!("{repo}/lfs/objects/{}/{}/{}", oid0, oid1, obj.oid); - - let result = match state - .s3_client - .head_object() - .bucket(&state.s3_bucket) - .key(&full_path) - .checksum_mode(aws_sdk_s3::types::ChecksumMode::Enabled) - .send() - .await - { - Ok(result) => result, - Err(e) => { - println!("Failed to HeadObject (repo {repo}, OID {}): {e}", obj.oid); - return BatchResponseObject::error( - obj, - StatusCode::INTERNAL_SERVER_ERROR, - "Failed to query object information".to_string(), - ); - } - }; - - // Scaleway actually doesn't provide SHA256 suport, but maybe in the future :) - if !validate_checksum(obj.oid, &result) { - return BatchResponseObject::error( - obj, - StatusCode::UNPROCESSABLE_ENTITY, - "Object corrupted".to_string(), - ); - } - if !validate_size(obj.size, &result) { - return BatchResponseObject::error( - obj, - StatusCode::UNPROCESSABLE_ENTITY, - "Incorrect size specified (or object corrupted)".to_string(), - ); - } - - let expires_in = std::time::Duration::from_secs(5 * 60); - let expires_at = Utc::now() + expires_in; - - if trusted { - let Ok(config) = aws_sdk_s3::presigning::PresigningConfig::expires_in(expires_in) else { - return BatchResponseObject::error( - obj, - StatusCode::INTERNAL_SERVER_ERROR, - "Failed to generate upload URL".to_string(), - ); - }; - let Ok(presigned) = state - .s3_client - .get_object() - .bucket(&state.s3_bucket) - .key(full_path) - .presigned(config) - .await - else { - return BatchResponseObject::error( - obj, - StatusCode::INTERNAL_SERVER_ERROR, - "Failed to generate upload URL".to_string(), - ); - }; - return BatchResponseObject { - oid: obj.oid, - size: obj.size, - authenticated: Some(true), - actions: BatchResponseObjectActions { - download: Some(BatchResponseObjectAction { - header: presigned - .headers() - .map(|(k, v)| (k.to_owned(), v.to_owned())) - .collect(), - expires_at, - href: presigned.uri().to_string(), - }), - ..Default::default() - }, - error: None, - }; - } - - if let Some(content_length) = result.content_length() { - if content_length > 0 { - match state - .dl_limiter - .lock() - .await - .request(content_length as u64) - .await - { - Ok(true) => {} - Ok(false) => { - return BatchResponseObject::error( - obj, - StatusCode::SERVICE_UNAVAILABLE, - "Public LFS downloads temporarily unavailable".to_string(), - ); - } - Err(e) => { - println!("Failed to request {content_length} bytes from download limiter: {e}"); - return BatchResponseObject::error( - obj, - StatusCode::INTERNAL_SERVER_ERROR, - "Internal server error".to_string(), - ); - } - } - } - } - - let Some(tag) = generate_tag( - Claims { - specific_claims: SpecificClaims::Download(obj.oid), - repo_path: repo, - expires_at, - }, - &state.authz_conf.key, - ) else { - return BatchResponseObject::error( - obj, - StatusCode::INTERNAL_SERVER_ERROR, - "Internal server error".to_string(), - ); - }; - - let upload_path = format!( - "{repo}/info/lfs/objects/{}/{}/{}", - HexByte(obj.oid[0]), - HexByte(obj.oid[1]), - obj.oid, - ); - - BatchResponseObject { - oid: obj.oid, - size: obj.size, - authenticated: Some(true), - actions: BatchResponseObjectActions { - download: Some(BatchResponseObjectAction { - header: { - let mut map = HashMap::new(); - map.insert( - "Authorization".to_string(), - format!("Gitolfs3-Hmac-Sha256 {tag} {}", expires_at.timestamp()), - ); - map - }, - expires_at, - href: format!("{}/{upload_path}", state.base_url), - }), - ..Default::default() - }, - error: None, - } -} - -struct AuthorizationConfig { - trusted_forwarded_hosts: HashSet, - key: Key, -} - -struct Trusted(bool); - -fn forwarded_from_trusted_host( - headers: &HeaderMap, - trusted: &HashSet, -) -> Result> { - if let Some(forwarded_host) = headers.get("X-Forwarded-Host") { - if let Ok(forwarded_host) = forwarded_host.to_str() { - if trusted.contains(forwarded_host) { - return Ok(true); - } - } else { - return Err(make_error_resp( - StatusCode::NOT_FOUND, - "Invalid X-Forwarded-Host header", - )); - } - } - Ok(false) -} - -const REPO_NOT_FOUND: GitLfsErrorResponse = - make_error_resp(StatusCode::NOT_FOUND, "Repository not found"); - -fn authorize_batch( - conf: &AuthorizationConfig, - repo_path: &str, - public: bool, - operation: Operation, - headers: &HeaderMap, -) -> Result> { - // - No authentication required for downloading exported repos - // - When authenticated: - // - Download / upload over presigned URLs - // - When accessing over Tailscale: - // - No authentication required for downloading from any repo - - let claims = VerifyClaimsInput { - specific_claims: SpecificClaims::BatchApi(operation), - repo_path, - }; - if !verify_claims(conf, &claims, headers)? { - return authorize_batch_unauthenticated(conf, public, operation, headers); - } - Ok(Trusted(true)) -} - -fn authorize_batch_unauthenticated( - conf: &AuthorizationConfig, - public: bool, - operation: Operation, - headers: &HeaderMap, -) -> Result> { - let trusted = forwarded_from_trusted_host(headers, &conf.trusted_forwarded_hosts)?; - match operation { - Operation::Upload => { - // Trusted users can clone all repositories (by virtue of accessing the server via a - // trusted network). However, they can not push without proper authentication. Untrusted - // users who are also not authenticated should not need to know which repositories exists. - // Therefore, we tell untrusted && unauthenticated users that the repo doesn't exist, but - // tell trusted users that they need to authenticate. - if !trusted { - return Err(REPO_NOT_FOUND); - } - Err(make_error_resp( - StatusCode::FORBIDDEN, - "Authentication required to upload", - )) - } - Operation::Download => { - // Again, trusted users can see all repos. For untrusted users, we first need to check - // whether the repo is public before we authorize. If the user is untrusted and the - // repo isn't public, we just act like it doesn't even exist. - if !trusted { - if !public { - return Err(REPO_NOT_FOUND); - } - return Ok(Trusted(false)); - } - Ok(Trusted(true)) - } - } -} - -fn repo_exists(name: &str) -> bool { - let Ok(metadata) = std::fs::metadata(name) else { - return false; - }; - metadata.is_dir() -} - -fn is_repo_public(name: &str) -> Option { - if !repo_exists(name) { - return None; - } - match std::fs::metadata(format!("{name}/git-daemon-export-ok")) { - Ok(metadata) if metadata.is_file() => Some(true), - Err(e) if e.kind() == std::io::ErrorKind::NotFound => Some(false), - _ => None, - } -} - -async fn batch( - State(state): State>, - headers: HeaderMap, - RepositoryName(repo): RepositoryName, - GitLfsJson(Json(payload)): GitLfsJson, -) -> Response { - let Some(public) = is_repo_public(&repo) else { - return REPO_NOT_FOUND.into_response(); - }; - let Trusted(trusted) = match authorize_batch( - &state.authz_conf, - &repo, - public, - payload.operation, - &headers, - ) { - Ok(authn) => authn, - Err(e) => return e.into_response(), - }; - - if !headers - .get_all("Accept") - .iter() - .filter_map(|v| v.to_str().ok()) - .any(is_git_lfs_json_mimetype) - { - let message = format!("Expected `{LFS_MIME}` in list of acceptable response media types"); - return make_error_resp(StatusCode::NOT_ACCEPTABLE, &message).into_response(); - } - - if payload.hash_algo != HashAlgo::Sha256 { - let message = "Unsupported hashing algorithm specified"; - return make_error_resp(StatusCode::CONFLICT, message).into_response(); - } - if !payload.transfers.is_empty() && !payload.transfers.contains(&TransferAdapter::Basic) { - let message = "Unsupported transfer adapter specified (supported: basic)"; - return make_error_resp(StatusCode::CONFLICT, message).into_response(); - } - - let mut resp = BatchResponse { - transfer: TransferAdapter::Basic, - objects: vec![], - hash_algo: HashAlgo::Sha256, - }; - for obj in payload.objects { - match payload.operation { - Operation::Download => resp - .objects - .push(handle_download_object(&state, &repo, &obj, trusted).await), - Operation::Upload => { - if let Some(obj_resp) = handle_upload_object(&state, &repo, &obj).await { - resp.objects.push(obj_resp); - } - } - }; - } - GitLfsJson(Json(resp)).into_response() -} - -#[derive(Deserialize, Copy, Clone)] -#[serde(remote = "Self")] -struct FileParams { - oid0: HexByte, - oid1: HexByte, - oid: Oid, -} - -impl<'de> Deserialize<'de> for FileParams { - fn deserialize(deserializer: D) -> Result - where - D: serde::Deserializer<'de>, - { - let unchecked @ FileParams { - oid0: HexByte(oid0), - oid1: HexByte(oid1), - oid, - } = FileParams::deserialize(deserializer)?; - if oid0 != oid.as_bytes()[0] { - return Err(de::Error::custom( - "first OID path part does not match first byte of full OID", - )); - } - if oid1 != oid.as_bytes()[1] { - return Err(de::Error::custom( - "second OID path part does not match first byte of full OID", - )); - } - Ok(unchecked) - } -} - -pub struct VerifyClaimsInput<'a> { - pub specific_claims: SpecificClaims, - pub repo_path: &'a str, -} - -fn verify_claims( - conf: &AuthorizationConfig, - claims: &VerifyClaimsInput, - headers: &HeaderMap, -) -> Result> { - const INVALID_AUTHZ_HEADER: GitLfsErrorResponse = - make_error_resp(StatusCode::BAD_REQUEST, "Invalid authorization header"); - - let Some(authz) = headers.get(header::AUTHORIZATION) else { - return Ok(false); - }; - let authz = authz.to_str().map_err(|_| INVALID_AUTHZ_HEADER)?; - let val = authz - .strip_prefix("Gitolfs3-Hmac-Sha256 ") - .ok_or(INVALID_AUTHZ_HEADER)?; - let (tag, expires_at) = val.split_once(' ').ok_or(INVALID_AUTHZ_HEADER)?; - let tag: Digest<32> = tag.parse().map_err(|_| INVALID_AUTHZ_HEADER)?; - let expires_at: i64 = expires_at.parse().map_err(|_| INVALID_AUTHZ_HEADER)?; - let expires_at = DateTime::::from_timestamp(expires_at, 0).ok_or(INVALID_AUTHZ_HEADER)?; - let expected_tag = generate_tag( - Claims { - specific_claims: claims.specific_claims, - repo_path: claims.repo_path, - expires_at, - }, - &conf.key, - ) - .ok_or_else(|| make_error_resp(StatusCode::INTERNAL_SERVER_ERROR, "Internal server error"))?; - if tag != expected_tag { - return Err(INVALID_AUTHZ_HEADER); - } - - Ok(true) -} - -fn authorize_get( - conf: &AuthorizationConfig, - repo_path: &str, - oid: Oid, - headers: &HeaderMap, -) -> Result<(), GitLfsErrorResponse<'static>> { - let claims = VerifyClaimsInput { - specific_claims: SpecificClaims::Download(oid), - repo_path, - }; - if !verify_claims(conf, &claims, headers)? { - return Err(make_error_resp( - StatusCode::UNAUTHORIZED, - "Repository not found", - )); - } - Ok(()) -} - -async fn obj_download( - State(state): State>, - headers: HeaderMap, - RepositoryName(repo): RepositoryName, - Path(FileParams { oid0, oid1, oid }): Path, -) -> Response { - if let Err(e) = authorize_get(&state.authz_conf, &repo, oid, &headers) { - return e.into_response(); - } - - let full_path = format!("{repo}/lfs/objects/{}/{}/{}", oid0, oid1, oid); - let result = match state - .s3_client - .get_object() - .bucket(&state.s3_bucket) - .key(full_path) - .checksum_mode(aws_sdk_s3::types::ChecksumMode::Enabled) - .send() - .await - { - Ok(result) => result, - Err(e) => { - println!("Failed to GetObject (repo {repo}, OID {oid}): {e}"); - return ( - StatusCode::INTERNAL_SERVER_ERROR, - "Failed to query object information", - ) - .into_response(); - } - }; - - let mut headers = header::HeaderMap::new(); - if let Some(content_type) = result.content_type { - let Ok(header_value) = content_type.try_into() else { - return ( - StatusCode::INTERNAL_SERVER_ERROR, - "Object has invalid content type", - ) - .into_response(); - }; - headers.insert(header::CONTENT_TYPE, header_value); - } - if let Some(content_length) = result.content_length { - headers.insert(header::CONTENT_LENGTH, content_length.into()); - } - - let async_read = result.body.into_async_read(); - let stream = tokio_util::io::ReaderStream::new(async_read); - let body = axum::body::Body::from_stream(stream); - - (headers, body).into_response() -} - -struct DownloadLimiter { - current: u64, - limit: u64, -} - -impl DownloadLimiter { - async fn new(limit: u64) -> DownloadLimiter { - let dlimit_str = match tokio::fs::read_to_string(".gitolfs3-dlimit").await { - Ok(dlimit_str) => dlimit_str, - Err(e) => { - println!("Failed to read download counter, assuming 0: {e}"); - return DownloadLimiter { current: 0, limit }; - } - }; - let current: u64 = match dlimit_str - .parse() - .map_err(|e| tokio::io::Error::new(tokio::io::ErrorKind::InvalidData, e)) - { - Ok(current) => current, - Err(e) => { - println!("Failed to read download counter, assuming 0: {e}"); - return DownloadLimiter { current: 0, limit }; - } - }; - DownloadLimiter { current, limit } - } - - async fn request(&mut self, n: u64) -> tokio::io::Result { - if self.current + n > self.limit { - return Ok(false); - } - self.current += n; - self.write_new_count().await?; - Ok(true) - } - - async fn reset(&mut self) { - self.current = 0; - if let Err(e) = self.write_new_count().await { - println!("Failed to reset download counter: {e}"); - } - } - - async fn write_new_count(&self) -> tokio::io::Result<()> { - let cwd = tokio::fs::File::open(std::env::current_dir()?).await?; - let mut file = tokio::fs::File::create(".gitolfs3-dlimit.tmp").await?; - file.write_all(self.current.to_string().as_bytes()).await?; - file.sync_all().await?; - tokio::fs::rename(".gitolfs3-dlimit.tmp", ".gitolfs3-dlimit").await?; - cwd.sync_all().await - } -} - -#[test] -fn test_mimetype() { - assert!(is_git_lfs_json_mimetype("application/vnd.git-lfs+json")); - assert!(!is_git_lfs_json_mimetype("application/vnd.git-lfs")); - assert!(!is_git_lfs_json_mimetype("application/json")); - assert!(is_git_lfs_json_mimetype( - "application/vnd.git-lfs+json; charset=utf-8" - )); - assert!(is_git_lfs_json_mimetype( - "application/vnd.git-lfs+json; charset=UTF-8" - )); - assert!(!is_git_lfs_json_mimetype( - "application/vnd.git-lfs+json; charset=ISO-8859-1" - )); -} - -#[test] -fn test_deserialize() { - let json = r#"{"operation":"upload","objects":[{"oid":"8f4123f9a7181f488c5e111d82cefd992e461ae5df01fd2254399e6e670b2d3c","size":170904}], - "transfers":["lfs-standalone-file","basic","ssh"],"ref":{"name":"refs/heads/main"},"hash_algo":"sha256"}"#; - let expected = BatchRequest { - operation: Operation::Upload, - objects: vec![BatchRequestObject { - oid: "8f4123f9a7181f488c5e111d82cefd992e461ae5df01fd2254399e6e670b2d3c" - .parse() - .unwrap(), - size: 170904, - }], - transfers: vec![ - TransferAdapter::Unknown, - TransferAdapter::Basic, - TransferAdapter::Unknown, - ], - hash_algo: HashAlgo::Sha256, - }; - assert_eq!( - serde_json::from_str::(json).unwrap(), - expected - ); -} - -#[test] -fn test_validate_claims() { - let key = "00232f7a019bd34e3921ee6c5f04caf48a4489d1be5d1999038950a7054e0bfea369ce2becc0f13fd3c69f8af2384a25b7ac2d52eb52c33722f3c00c50d4c9c2"; - let key: Key = key.parse().unwrap(); - - let claims = Claims { - expires_at: Utc::now() + std::time::Duration::from_secs(5 * 60), - repo_path: "lfs-test.git", - specific_claims: SpecificClaims::BatchApi(Operation::Download), - }; - let tag = generate_tag(claims, &key).unwrap(); - let header_value = format!( - "Gitolfs3-Hmac-Sha256 {tag} {}", - claims.expires_at.timestamp() - ); - - let conf = AuthorizationConfig { - key, - trusted_forwarded_hosts: HashSet::new(), - }; - let verification_claims = VerifyClaimsInput { - repo_path: claims.repo_path, - specific_claims: claims.specific_claims, - }; - let mut headers = HeaderMap::new(); - headers.insert(header::AUTHORIZATION, header_value.try_into().unwrap()); - - assert!(verify_claims(&conf, &verification_claims, &headers).unwrap()); -} -- cgit v1.2.3