requestbody: Allow overwriting remote address

An experimental feature, let's see if it's useful.

1 files changed, 9 insertions, 0 deletions

diff --git a/modules/caddyhttp/requestbody/requestbody.go b/modules/caddyhttp/requestbody/requestbody.go
index 76cd274..35aa1af 100644
--- a/modules/caddyhttp/requestbody/requestbody.go
+++ b/modules/caddyhttp/requestbody/requestbody.go
@@ -29,6 +29,11 @@ func init() {
 type RequestBody struct {
 	// The maximum number of bytes to allow reading from the body by a later handler.
 	MaxSize int64 `json:"max_size,omitempty"`
+
+	// Overwrites the remote address from which the request came. This is destructive;
+	// handlers later in the chain will not be able to recover the true originating
+	// address of the request. EXPERIMENTAL: May get changed or removed later.
+	RemoteAddress string `json:"remote_address,omitempty"`
 }
 
 // CaddyModule returns the Caddy module information.
@@ -40,6 +45,10 @@ func (RequestBody) CaddyModule() caddy.ModuleInfo {
 }
 
 func (rb RequestBody) ServeHTTP(w http.ResponseWriter, r *http.Request, next caddyhttp.Handler) error {
+	if rb.RemoteAddress != "" {
+		repl := r.Context().Value(caddy.ReplacerCtxKey).(*caddy.Replacer)
+		r.RemoteAddr = repl.ReplaceAll(rb.RemoteAddress, "")
+	}
 	if r.Body == nil {
 		return next.ServeHTTP(w, r)
 	}