mirror of
https://codeberg.org/forgejo/forgejo
synced 2024-11-30 13:56:09 +01:00
4e98224a45
When `webhook.PROXY_URL` has been set, the old code will check if the proxy host is in `ALLOWED_HOST_LIST` or reject requests through the proxy. It requires users to add the proxy host to `ALLOWED_HOST_LIST`. However, it actually allows all requests to any port on the host, when the proxy host is probably an internal address. But things may be even worse. `ALLOWED_HOST_LIST` doesn't really work when requests are sent to the allowed proxy, and the proxy could forward them to any hosts. This PR fixes it by: - If the proxy has been set, always allow connectioins to the host and port. - Check `ALLOWED_HOST_LIST` before forwarding.
70 lines
2.6 KiB
Go
70 lines
2.6 KiB
Go
// Copyright 2021 The Gitea Authors. All rights reserved.
|
|
// SPDX-License-Identifier: MIT
|
|
|
|
package hostmatcher
|
|
|
|
import (
|
|
"context"
|
|
"fmt"
|
|
"net"
|
|
"net/url"
|
|
"syscall"
|
|
"time"
|
|
)
|
|
|
|
// NewDialContext returns a DialContext for Transport, the DialContext will do allow/block list check
|
|
func NewDialContext(usage string, allowList, blockList *HostMatchList) func(ctx context.Context, network, addr string) (net.Conn, error) {
|
|
return NewDialContextWithProxy(usage, allowList, blockList, nil)
|
|
}
|
|
|
|
func NewDialContextWithProxy(usage string, allowList, blockList *HostMatchList, proxy *url.URL) func(ctx context.Context, network, addr string) (net.Conn, error) {
|
|
// How Go HTTP Client works with redirection:
|
|
// transport.RoundTrip URL=http://domain.com, Host=domain.com
|
|
// transport.DialContext addrOrHost=domain.com:80
|
|
// dialer.Control tcp4:11.22.33.44:80
|
|
// transport.RoundTrip URL=http://www.domain.com/, Host=(empty here, in the direction, HTTP client doesn't fill the Host field)
|
|
// transport.DialContext addrOrHost=domain.com:80
|
|
// dialer.Control tcp4:11.22.33.44:80
|
|
return func(ctx context.Context, network, addrOrHost string) (net.Conn, error) {
|
|
dialer := net.Dialer{
|
|
// default values comes from http.DefaultTransport
|
|
Timeout: 30 * time.Second,
|
|
KeepAlive: 30 * time.Second,
|
|
|
|
Control: func(network, ipAddr string, c syscall.RawConn) error {
|
|
host, port, err := net.SplitHostPort(addrOrHost)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
if proxy != nil {
|
|
// Always allow the host of the proxy, but only on the specified port.
|
|
if host == proxy.Hostname() && port == proxy.Port() {
|
|
return nil
|
|
}
|
|
}
|
|
|
|
// in Control func, the addr was already resolved to IP:PORT format, there is no cost to do ResolveTCPAddr here
|
|
tcpAddr, err := net.ResolveTCPAddr(network, ipAddr)
|
|
if err != nil {
|
|
return fmt.Errorf("%s can only call HTTP servers via TCP, deny '%s(%s:%s)', err=%w", usage, host, network, ipAddr, err)
|
|
}
|
|
|
|
var blockedError error
|
|
if blockList.MatchHostOrIP(host, tcpAddr.IP) {
|
|
blockedError = fmt.Errorf("%s can not call blocked HTTP servers (check your %s setting), deny '%s(%s)'", usage, blockList.SettingKeyHint, host, ipAddr)
|
|
}
|
|
|
|
// if we have an allow-list, check the allow-list first
|
|
if !allowList.IsEmpty() {
|
|
if !allowList.MatchHostOrIP(host, tcpAddr.IP) {
|
|
return fmt.Errorf("%s can only call allowed HTTP servers (check your %s setting), deny '%s(%s)'", usage, allowList.SettingKeyHint, host, ipAddr)
|
|
}
|
|
}
|
|
// otherwise, we always follow the blocked list
|
|
return blockedError
|
|
},
|
|
}
|
|
return dialer.DialContext(ctx, network, addrOrHost)
|
|
}
|
|
}
|