From 503e64c84b9f6d3da5bc0a7ca15039360cea01f2 Mon Sep 17 00:00:00 2001
From: user <40304161+fullylegit@users.noreply.github.com>
Date: Wed, 19 Nov 2025 23:48:04 +1100
Subject: [PATCH] Fixed a panic when the checksum contained multi-byte
 characters

- Check that the entire sentence is ASCII as per the standard
---
 CHANGELOG.md |  1 +
 src/lib.rs   | 16 ++++++++++++++--
 2 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 26e5807..3a3a3c8 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ## [Unreleased]
 ### Added
 ### Changed
+- Fixed panic on messages with multi-byte characters in the checksum
 
 ## [0.11.0] - 2024-06-13
 ### Added
diff --git a/src/lib.rs b/src/lib.rs
index f4342dc..be2972c 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -286,6 +286,12 @@ impl NmeaParser {
             }
         };
 
+        if !sentence.is_ascii() {
+            return Err(ParseError::InvalidSentence(String::from(
+                "Invalid characters in sentence",
+            )));
+        }
+
         // Calculate NMEA checksum and compare it to the given one. Also, remove the checksum part
         // from the sentence to simplify next processing steps.
         let mut checksum = 0;
@@ -625,9 +631,9 @@ mod test {
     fn test_parse_invalid_sentence() {
         let mut p = NmeaParser::new();
         assert_eq!(
-            p.parse_sentence("$޴GAGSV,,"),
+            p.parse_sentence("$GAGSV^,,"),
             Err(ParseError::InvalidSentence(
-                "Invalid characters in sentence type: $\u{7b4}GAGSV".to_string()
+                "Invalid characters in sentence type: $GAGSV^".to_string()
             ))
         );
         assert_eq!(
@@ -648,6 +654,12 @@ mod test {
                 "Invalid NMEA sentence: !".to_string()
             ))
         );
+        assert_eq!(
+            p.parse_sentence("$GAGSV,,*💖"),
+            Err(ParseError::InvalidSentence(
+                "Invalid characters in sentence".to_string()
+            ))
+        );
     }
     #[test]
     fn test_parse_prefix_chars() {