swadhinbiswas sec(fuzz): add cargo-fuzz targets for parser and protocol attack surfaces · 7/9/2026
e086c74
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#![no_main]
use libfuzzer_sys::fuzz_target;
use std::path::Path;
fuzz_target!(|data: &[u8]| {
if data.is_empty() {
return;
}
if let Ok(s) = std::str::from_utf8(data) {
// Sanitize path: prevent directory traversal
let path = Path::new(s);
let _ = path.components().collect::<Vec<_>>();
// Check for path traversal patterns
let normalized = s.replace('\\', "/");
let has_traversal = normalized.contains("..");
let has_null = s.contains('\0');
let has_absolute = normalized.starts_with('/');
// Simulate path join and canonicalization
let base = Path::new("/var/www/static");
let joined = base.join(path);
let _ = joined.strip_prefix("/var/www/static");
// Fuzz MIME type detection by extension
if let Some(ext) = path.extension().and_then(|e| e.to_str()) {
let mime = match ext.to_lowercase().as_str() {
"html" | "htm" => "text/html",
"css" => "text/css",
"js" => "application/javascript",
"json" => "application/json",
"png" => "image/png",
"jpg" | "jpeg" => "image/jpeg",
"gif" => "image/gif",
"svg" => "image/svg+xml",
"ico" => "image/x-icon",
"woff2" => "font/woff2",
_ => "application/octet-stream",
};
let _ = mime;
}
// Fuzz percent-decoding (as used in URL path segments)
let mut decoded = String::with_capacity(s.len());
let mut chars = s.chars();
while let Some(c) = chars.next() {
if c == '%' {
let hex: String = chars.by_ref().take(2).collect();
if hex.len() == 2 {
if let Ok(byte) = u8::from_str_radix(&hex, 16) {
decoded.push(byte as char);
}
}
} else {
decoded.push(c);
}
}
let _ = decoded;
}
});