From bff28c0bfe8476f7d7a2fc5ed75da927a1306bac Mon Sep 17 00:00:00 2001
From: Niklas Fiekas <niklas.fiekas@backscattering.de>
Date: Wed, 27 Mar 2024 20:36:46 +0100
Subject: [PATCH] cap more field sizes and relax fuzzer

---
 fuzz/src/lib.rs | 28 ++++++++++++++--------------
 src/header.rs   |  9 +++++----
 2 files changed, 19 insertions(+), 18 deletions(-)

diff --git a/fuzz/src/lib.rs b/fuzz/src/lib.rs
index 0dae460..ee4733a 100644
--- a/fuzz/src/lib.rs
+++ b/fuzz/src/lib.rs
@@ -1,4 +1,5 @@
 use arbitrary::{Arbitrary, Unstructured};
+use std::cmp::min;
 
 #[derive(Clone, Default, Debug, Eq, PartialEq, Arbitrary)]
 pub struct Model {
@@ -76,21 +77,21 @@ impl Arbitrary<'_> for Identifier {
     }
 }
 
-#[derive(Copy, Clone, Debug, Eq, PartialEq)]
+#[derive(Copy, Clone, Debug, Eq, Arbitrary)]
 struct Mode(u32);
 
-impl Arbitrary<'_> for Mode {
-    fn arbitrary(u: &mut Unstructured<'_>) -> arbitrary::Result<Self> {
-        u32::arbitrary(u).map(|v| Mode(v & 0o7777))
+impl PartialEq for Mode {
+    fn eq(&self, other: &Mode) -> bool {
+        self.0 & 0o7777_7777 == other.0 & 0o7777_7777
     }
 }
 
-#[derive(Copy, Clone, Debug, Eq, PartialEq)]
+#[derive(Copy, Clone, Debug, Eq, Arbitrary)]
 struct Timestamp(u64);
 
-impl Arbitrary<'_> for Timestamp {
-    fn arbitrary(u: &mut Unstructured<'_>) -> arbitrary::Result<Self> {
-        u.int_in_range(0..=999_999_999_999).map(Timestamp) // TODO: Deal with entire range
+impl PartialEq for Timestamp {
+    fn eq(&self, other: &Timestamp) -> bool {
+        min(self.0, 999_999_999_999) == min(other.0, 999_999_999_999)
     }
 }
 
@@ -99,11 +100,10 @@ struct Uid(u32);
 
 impl PartialEq for Uid {
     fn eq(&self, other: &Uid) -> bool {
-        truncated_ascii(self.0.to_string(), 6) == truncated_ascii(other.0.to_string(), 6)
+        let mut left = self.0.to_string();
+        left.truncate(6);
+        let mut right = other.0.to_string();
+        right.truncate(6);
+        left == right
     }
 }
-
-fn truncated_ascii(mut ascii: String, width: usize) -> String {
-    ascii.truncate(width);
-    ascii
-}
diff --git a/src/header.rs b/src/header.rs
index 9d9d556..4274d90 100644
--- a/src/header.rs
+++ b/src/header.rs
@@ -1,3 +1,4 @@
+use std::cmp::min;
 use std::collections::HashMap;
 use std::fs::Metadata;
 use std::io::{self, Error, ErrorKind, Read, Result, Write};
@@ -244,10 +245,10 @@ impl Header {
                 writer,
                 "#1/{:<13}{:<12}{:<6.6}{:<6.6}{:<8o}{:<10}`",
                 padded_length,
-                self.mtime,
+                min(self.mtime, 999_999_999_999),
                 self.uid.to_string(),
                 self.gid.to_string(),
-                self.mode,
+                self.mode & 0o7777_7777,
                 self.size + padded_length as u64
             )?;
             writer.write_all(&self.identifier)?;
@@ -258,10 +259,10 @@ impl Header {
             writeln!(
                 writer,
                 "{:<12}{:<6.6}{:<6.6}{:<8o}{:<10}`",
-                self.mtime,
+                min(self.mtime, 999_999_999_999),
                 self.uid.to_string(),
                 self.gid.to_string(),
-                self.mode,
+                self.mode & 0o7777_7777,
                 self.size
             )?;
         }