Update error deserialization in compliance with BOLT #1

[rust-lightning] / src / ln / msgs.rs

diff --git a/src/ln/msgs.rs b/src/ln/msgs.rs
index 4500ee2f89f48bee0290257c3c49411169cc0c07..44d71bd332938bc3959f3cf768bfebe5bffcbdcb 100644 (file)
--- a/src/ln/msgs.rs
+++ b/src/ln/msgs.rs
@@ -5,7 +5,7 @@ use bitcoin::network::serialize::{deserialize,serialize};
 use bitcoin::blockdata::script::Script;
 
 use std::error::Error;
-use std::fmt;
+use std::{cmp, fmt};
 use std::result::Result;
 
 use util::{byte_utils, internal_traits, events};
@@ -1626,11 +1626,9 @@ impl MsgDecodable for ErrorMessage {
                if v.len() < 34 {
                        return Err(DecodeError::ShortRead);
                }
-               let len = byte_utils::slice_to_be16(&v[32..34]);
-               if v.len() < 34 + len as usize {
-                       return Err(DecodeError::ShortRead);
-               }
-               let data = match String::from_utf8(v[34..34 + len as usize].to_vec()) {
+               // Unlike most messages, BOLT 1 requires we truncate our read if the value is out of range
+               let len = cmp::min(byte_utils::slice_to_be16(&v[32..34]) as usize, v.len() - 34);
+               let data = match String::from_utf8(v[34..34 + len].to_vec()) {
                        Ok(s) => s,
                        Err(_) => return Err(DecodeError::BadText),
                };