// Copyright 2023 Google LLC

//

// Licensed under the Apache License, Version 2.0 (the "License");

// you may not use this file except in compliance with the License.

// You may obtain a copy of the License at

//

//      http://www.apache.org/licenses/LICENSE-2.0

//

// Unless required by applicable law or agreed to in writing, software

// distributed under the License is distributed on an "AS IS" BASIS,

// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

// See the License for the specific language governing permissions and

//limitations under the License.

//

//###################

#![no_main]

use arbitrary::Arbitrary;

use libfuzzer_sys::fuzz_target;

use std::hint::black_box;

use std::io::Cursor;

#[derive(Arbitrary, Debug)]

Unexecuted instantiation: <structured_fuzz_reader::ReadOperations as arbitrary::Arbitrary>::try_size_hint::{closure#0}

Unexecuted instantiation: <structured_fuzz_reader::ReadOperations as arbitrary::Arbitrary>::arbitrary_take_rest::{closure#0}

Unexecuted instantiation: <structured_fuzz_reader::ReadOperations as arbitrary::Arbitrary>::arbitrary::{closure#0}

enum ReadOperations<'a> {

    ReadByName(String),

    ReadByNameDecrypt { name: String, password: &'a [u8] },

    ReadByIterableNames,

    ReadByIndex(usize),

    ReadByIndexDecrypt { index: usize, password: &'a [u8] },

    ReadByIterableIndicies,

    ReadComment,

}

#[derive(Arbitrary, Debug)]

Unexecuted instantiation: <structured_fuzz_reader::Driver as arbitrary::Arbitrary>::arbitrary::{closure#0}

Unexecuted instantiation: <structured_fuzz_reader::Driver as arbitrary::Arbitrary>::try_size_hint::{closure#0}

Unexecuted instantiation: <structured_fuzz_reader::Driver as arbitrary::Arbitrary>::arbitrary_take_rest::{closure#0}

#[repr(C)]

struct Driver<'a> {

    // NOTE: we are defining repr(C) so that the struct field ordering is consistent.

    // This consistent ordering means that we still generate a set of zip files

    // for the fuzz corpus, which will become the .zip_file, and any leftover data

    // will be used for structured fuzzing.

    zip_file: &'a [u8],

    read_operations: Vec<ReadOperations<'a>>,

}

fn read_file_attributes(file: &mut zip::read::ZipFile) -> Result<(), zip::result::ZipError> {

    use std::io::Read;

    let _unused = black_box(file.name());

    let _unused = black_box(file.mangled_name());

    let _unused = black_box(file.enclosed_name());

    let _unused = black_box(file.compression());

    let _unused = black_box(file.compressed_size());

    let _unused = black_box(file.size());

    let _unused = black_box(file.last_modified());

    let _unused = black_box(file.is_dir());

    let _unused = black_box(file.is_file());

    let _unused = black_box(file.unix_mode());

    let _unused = black_box(file.crc32());

    let _unused = black_box(file.data_start());

    let _unused = black_box(file.header_start());

    let _unused = black_box(file.central_header_start());

    let mut s: String = String::new();

    let _unused = black_box(file.read_to_string(&mut s));

    return Ok(());

}

fn fuzzed_extract(driver: Driver) -> Result<(), zip::result::ZipError> {

    match zip::ZipArchive::new(Cursor::new(driver.zip_file)) {

        Ok(mut archive) => {

            for operation in driver.read_operations.iter() {

                match operation {

                    ReadOperations::ReadByName(name) => {

                        let mut file = archive.by_name(name)?;

                        let _unused = black_box(read_file_attributes(&mut file));

                    }

                    // TODO: This could probably use a custom mutator, or a specialised seed corpus.

                    // The probability that the fuzzer guesses the correct password is exceedingly low.

                    ReadOperations::ReadByNameDecrypt { name, password } => {

                        match archive.by_name_decrypt(name, password)? {

                            Ok(mut file) => {

                                let _unused = black_box(&read_file_attributes(&mut file));

                            }

                            Err(e) => {

                                let _unused = black_box(format!("{e:?}"));

                                let _unused = black_box(format!("{e:#?}"));

                            }

                        }

                    }

                    ReadOperations::ReadByIterableNames => {

                        let names: Vec<String> =

                            archive.file_names().map(|x| x.to_string()).collect();

                        for name in names.iter() {

                            let mut file = archive.by_name(&name)?;

                            let _unused = black_box(read_file_attributes(&mut file));

                        }

                    }

                    ReadOperations::ReadByIndex(index) => {

                        let mut file = archive.by_index(*index)?;

                        let _unused = black_box(read_file_attributes(&mut file));

                    }

                    ReadOperations::ReadByIndexDecrypt { index, password } => {

                        match archive.by_index_decrypt(*index, password)? {

                            Ok(mut file) => {

                                let _unused = black_box(read_file_attributes(&mut file));

                            }

                            Err(e) => {

                                let _unused = black_box(format!("{e:?}"));

                                let _unused = black_box(format!("{e:#?}"));

                            }

                        }

                    }

                    ReadOperations::ReadByIterableIndicies => {

                        for i in 0..archive.len() {

                            let mut file = archive.by_index(i)?;

                            let _unused = black_box(read_file_attributes(&mut file));

                        }

                    }

                    ReadOperations::ReadComment => {

                        let _unused = black_box(archive.comment());

                    }

                }

            }

        }

        Err(e) => return Err(e),

    }

    return Ok(());

}

fuzz_target!(|driver: Driver| {

    if let Err(e) = fuzzed_extract(driver) {

        let _unused = black_box(format!("{e:?}"));

        let _unused = black_box(format!("{e:#?}"));

    }

});