//! Fuzz the standard security handler.
//!
//! The /Encrypt dictionary and every value key derivation consumes are
//! attacker-controlled: /O, /U, /P, /Length, the crypt filter names and the
//! file id all come straight from the file. A malformed one must produce a
//! typed error, never a panic or an unbounded loop.
#![no_main]

use libfuzzer_sys::fuzz_target;
use nigig_pdf_cos::encrypt::Decryptor;
use nigig_pdf_cos::{Lexer, PdfObj};
use nigig_pdf_document::PdfDocument;

fuzz_target!(|data: &[u8]| {
    // Interpret the input as an /Encrypt dictionary where it parses as one.
    let mut lexer = Lexer::new(data, 0);
    if let Ok(PdfObj::Dict(dict)) = lexer.read_object() {
        // Both an empty and a non-empty password: the two authentication
        // paths differ, and the owner-password path re-derives the key.
        let _ = Decryptor::new(&dict, data, b"");
        let _ = Decryptor::new(&dict, data, data);
    }

    // And as a whole document, which reaches key derivation through the
    // real trailer path.
    if let Ok(mut doc) = PdfDocument::parse(data) {
        for index in 0..doc.page_count().min(2) {
            let _ = doc.page(index);
        }
    }
    let _ = PdfDocument::parse_with_password(data, b"password");
});