fuzzing: add a new fuzzer for cksum

fuzz/fuzz_targets/fuzz_cksum.rs

@@ -0,0 +1,164 @@
+// This file is part of the uutils coreutils package.
+//
+// For the full copyright and license information, please view the LICENSE
+// file that was distributed with this source code.
+// spell-checker:ignore chdir
+
+#![no_main]
+use libfuzzer_sys::fuzz_target;
+use std::ffi::OsString;
+use uu_cksum::uumain;
+mod fuzz_common;
+use crate::fuzz_common::{
+    compare_result, generate_and_run_uumain, generate_random_file, generate_random_string,
+    run_gnu_cmd, CommandResult,
+};
+use rand::Rng;
+use std::env::temp_dir;
+use std::fs::{self, File};
+use std::io::Write;
+use std::process::Command;
+
+static CMD_PATH: &str = "cksum";
+
+fn generate_cksum_args() -> Vec<String> {
+    let mut rng = rand::thread_rng();
+    let mut args = Vec::new();
+
+    let digests = [
+        "sysv", "bsd", "crc", "md5", "sha1", "sha224", "sha256", "sha384", "sha512", "blake2b",
+        "sm3",
+    ];
+    let digest_opts = [
+        "--base64",
+        "--raw",
+        "--tag",
+        "--untagged",
+        "--text",
+        "--binary",
+    ];
+
+    if rng.gen_bool(0.3) {
+        args.push("-a".to_string());
+        args.push(digests[rng.gen_range(0..digests.len())].to_string());
+    }
+
+    if rng.gen_bool(0.2) {
+        args.push(digest_opts[rng.gen_range(0..digest_opts.len())].to_string());
+    }
+
+    if rng.gen_bool(0.15) {
+        args.push("-l".to_string());
+        args.push(rng.gen_range(8..513).to_string());
+    }
+
+    if rng.gen_bool(0.05) {
+        for _ in 0..rng.gen_range(0..3) {
+            args.push(format!("file_{}", generate_random_string(5)));
+        }
+    } else {
+        args.push("-c".to_string());
+    }
+
+    if rng.gen_bool(0.25) {
+        if let Ok(file_path) = generate_random_file() {
+            args.push(file_path);
+        }
+    }
+
+    if args.is_empty() || !args.iter().any(|arg| arg.starts_with("file_")) {
+        args.push("-a".to_string());
+        args.push(digests[rng.gen_range(0..digests.len())].to_string());
+
+        if let Ok(file_path) = generate_random_file() {
+            args.push(file_path);
+        }
+    }
+
+    args
+}
+
+fn generate_checksum_file(
+    algo: &str,
+    file_path: &str,
+    digest_opts: &[&str],
+) -> Result<String, std::io::Error> {
+    let checksum_file_path = temp_dir().join("checksum_file");
+    let mut cmd = Command::new(CMD_PATH);
+    cmd.arg("-a").arg(algo);
+
+    for opt in digest_opts {
+        cmd.arg(opt);
+    }
+
+    cmd.arg(file_path);
+    let output = cmd.output()?;
+
+    let mut checksum_file = File::create(&checksum_file_path)?;
+    checksum_file.write_all(&output.stdout)?;
+
+    Ok(checksum_file_path.to_str().unwrap().to_string())
+}
+
+fn select_random_digest_opts<'a>(
+    rng: &mut rand::rngs::ThreadRng,
+    digest_opts: &'a [&'a str],
+) -> Vec<&'a str> {
+    digest_opts
+        .iter()
+        .filter(|_| rng.gen_bool(0.5))
+        .copied()
+        .collect()
+}
+
+fuzz_target!(|_data: &[u8]| {
+    let cksum_args = generate_cksum_args();
+    let mut args = vec![OsString::from("cksum")];
+    args.extend(cksum_args.iter().map(OsString::from));
+
+    if let Ok(file_path) = generate_random_file() {
+        let algo = cksum_args
+            .iter()
+            .position(|arg| arg == "-a")
+            .map_or("md5", |index| &cksum_args[index + 1]);
+
+        let all_digest_opts = ["--base64", "--raw", "--tag", "--untagged"];
+        let mut rng = rand::thread_rng();
+        let selected_digest_opts = select_random_digest_opts(&mut rng, &all_digest_opts);
+
+        if let Ok(checksum_file_path) =
+            generate_checksum_file(algo, &file_path, &selected_digest_opts)
+        {
+            if let Ok(content) = fs::read_to_string(&checksum_file_path) {
+                println!("File content: {checksum_file_path}={content}");
+            } else {
+                eprintln!("Error reading the checksum file.");
+            }
+            println!("args: {:?}", args);
+            let rust_result = generate_and_run_uumain(&args, uumain, None);
+
+            let gnu_result = match run_gnu_cmd(CMD_PATH, &args[1..], false, None) {
+                Ok(result) => result,
+                Err(error_result) => {
+                    eprintln!("Failed to run GNU command:");
+                    eprintln!("Stderr: {}", error_result.stderr);
+                    eprintln!("Exit Code: {}", error_result.exit_code);
+                    CommandResult {
+                        stdout: String::new(),
+                        stderr: error_result.stderr,
+                        exit_code: error_result.exit_code,
+                    }
+                }
+            };
+
+            compare_result(
+                "cksum",
+                &format!("{:?}", &args[1..]),
+                None,
+                &rust_result,
+                &gnu_result,
+                false,
+            );
+        }
+    }
+});