mod cmd;
use std::io::{self, Read, Write};
use std::path::PathBuf;
use std::sync::OnceLock;
use std::time::SystemTime;
use std::{env, fs, process};
use lessify::Pager;
use jolokia::traits::Cipher;
use cmd::{cli, ui};
fn main() {
let args = match cli::Args::build_from_args(env::args().skip(1)) {
Ok(args) => args,
Err(err) => {
eprintln!(
"\
{fatal}: {err}.
Try '{bin} -h' for help.",
fatal = ui::Color::error("fatal"),
bin = env!("CARGO_BIN_NAME")
);
process::exit(2);
}
};
if args.long_help {
long_help();
} else if args.short_help {
short_help();
} else if args.version {
version();
} else if let Some(command) = args.command {
if let Err(reason) = execute_command(command, &args) {
eprintln!(
"{error}: {reason}{}",
if reason.ends_with('.') { "" } else { "." },
error = ui::Color::error("error"),
);
process::exit(1);
}
} else {
short_help();
}
}
fn execute_command(command: cli::Command, args: &cli::Args) -> Result<(), String> {
let algorithm = args.algorithm.unwrap_or_default();
let cipher: Box<dyn Cipher> = algorithm.into();
let add_newline = !matches!(args.output, cli::Output::Redirected);
match command {
cli::Command::GenKey => cmd::genkey(cipher.as_ref(), add_newline),
cli::Command::Encrypt | cli::Command::Decrypt => {
let is_in_place = is_input_file_used_for_output(args);
let key = get_key_or_default(args, algorithm);
let message = get_message_or_exit(args);
let output = if is_in_place {
get_temporary_file_or_exit(args)
} else {
get_output_or_exit(args)
};
if command == cli::Command::Encrypt {
cmd::encrypt(cipher.as_ref(), key, message, output, args.raw, add_newline)?;
} else if command == cli::Command::Decrypt {
cmd::decrypt(cipher.as_ref(), key, message, output, args.raw)?;
}
if is_in_place {
override_output_file_with_temporary_file_or_exit(args);
}
Ok(())
}
}
}
fn is_input_file_used_for_output(args: &cli::Args) -> bool {
let (Some(cli::Message::File(input_file)), cli::Output::File(output_file)) =
(&args.message, &args.output)
else {
return false;
};
let (Ok(input_file), Ok(output_file)) = (input_file.canonicalize(), output_file.canonicalize())
else {
return false;
};
input_file == output_file
}
fn get_key_or_default(args: &cli::Args, algorithm: cli::Algorithm) -> &str {
if let Some(ref key) = args.key {
key.as_str()
} else if algorithm == cli::Algorithm::RotN || algorithm == cli::Algorithm::Brainfuck {
algorithm.default_key()
} else {
eprintln!(
"\
{warning}: Using {package}'s default cipher key.
{b}THIS IS NOT SECURE!{rt}
Anyone using {package} will be able to decrypt your messages. To generate
a unique cipher key, run `{bin} genkey`, and use it on the command line
with `--key`, or set the `{key_env_var}` environment variable.",
warning = ui::Color::warning("warning"),
package = env!("CARGO_PKG_NAME"),
bin = env!("CARGO_BIN_NAME"),
key_env_var = cli::KEY_ENV_VAR,
b = ui::Color::maybe_color(ui::color::BOLD),
rt = ui::Color::maybe_color(ui::color::RESET),
);
algorithm.default_key()
}
}
fn get_message_or_exit(args: &cli::Args) -> Box<dyn Read> {
if let Some(ref message) = args.message {
match message {
cli::Message::String(message) => Box::new(io::Cursor::new(message.to_owned())),
cli::Message::File(file) => {
let f = match fs::File::open(file) {
Ok(f) => f,
Err(reason) => {
eprintln!(
"{error}: Could not read '{}': {reason}.",
file.display(),
error = ui::Color::error("error")
);
process::exit(1);
}
};
let reader = io::BufReader::new(f);
Box::new(reader)
}
cli::Message::Stdin => Box::new(io::stdin()),
}
} else {
eprintln!(
"{fatal}: You must provide a message.",
fatal = ui::Color::error("fatal")
);
process::exit(2);
}
}
fn get_output_or_exit(args: &cli::Args) -> Box<dyn Write> {
match args.output {
cli::Output::File(ref file) => {
let f = match fs::File::create(file) {
Ok(f) => f,
Err(reason) => {
eprintln!(
"{error}: Could not open file for writing '{}': {reason}.",
file.display(),
error = ui::Color::error("error")
);
process::exit(1);
}
};
let writer = io::BufWriter::new(f);
Box::new(writer)
}
cli::Output::Stdout | cli::Output::Redirected => Box::new(io::stdout()),
}
}
fn get_temporary_file_or_exit(args: &cli::Args) -> Box<dyn Write> {
debug_assert!(
is_input_file_used_for_output(args),
"Should only get called if in-place ciphering."
);
let tmp_file = build_temporary_file_path(args);
let f = match fs::File::create(&tmp_file) {
Ok(f) => f,
Err(reason) => {
eprintln!(
"{error}: Could not open file for writing '{}': {reason}.",
tmp_file.display(),
error = ui::Color::error("error")
);
process::exit(1);
}
};
let writer = io::BufWriter::new(f);
Box::new(writer)
}
fn override_output_file_with_temporary_file_or_exit(args: &cli::Args) {
debug_assert!(
is_input_file_used_for_output(args),
"Should only get called if in-place ciphering."
);
let cli::Output::File(ref file) = args.output else {
unreachable!("if in-place, it's necessarily a file");
};
let tmp_file = build_temporary_file_path(args);
if let Err(reason) = std::fs::rename(tmp_file, file) {
eprintln!(
"{error}: Could not override '{}': {reason}.",
file.display(),
error = ui::Color::error("error")
);
process::exit(1);
}
}
fn build_temporary_file_path(args: &cli::Args) -> PathBuf {
static EXTENSION: OnceLock<String> = OnceLock::new();
let cli::Output::File(ref file) = args.output else {
unreachable!("if in-place, it's necessarily a file");
};
file.with_extension(EXTENSION.get_or_init(|| {
let mut extension = env!("CARGO_CRATE_NAME").to_string();
if let Ok(timestamp) = SystemTime::now()
.duration_since(SystemTime::UNIX_EPOCH)
.map(|t| t.as_micros())
{
extension = format!("{timestamp}.{extension}");
}
extension
}))
}
fn short_help() {
println!("{}", short_help_message());
println!(
"For full help, see `{bin} --help`.",
bin = env!("CARGO_BIN_NAME")
);
}
fn short_help_message() -> String {
format!(
"\
{description}
Usage: {bin} [<options>] <command> [<args>]
Commands:
genkey Generate cipher key
encrypt Encrypt plaintext
decrypt Decrypt ciphertext
Args:
<MESSAGE>
-k, --key <KEY> Cipher key (base64)
-r, --raw Handle message as raw binary
-f, --file <FILE> Read message from file
-o, --output <FILE> Write output to file
Options:
-h, --help Show this message and exit
-V, --version Show the version and exit
-v, --verbose Show files being copied
",
description = env!("CARGO_PKG_DESCRIPTION"),
bin = env!("CARGO_BIN_NAME"),
)
}
#[allow(clippy::too_many_lines)]
fn long_help() {
Pager::page_or_print(&format!(
"\
{help}
What does {package} do?
TODO: Lorem ipsum {bin}.
symmetric encryption (explain),
need a key
Algorithms:
{u}Name{rt} {u}Key Size{rt}
ChaCha20-Poly1305 32-bytes (256-bits)
ROT-n 0..255 (insecure)
Key:
In {package}, a key is always a base64-encoded string of bytes. The
size of the key varies depending on the selected algorithm.
To generate a new key run:
{h}${rt} {bin} genkey
hNbaua5cGlUNsEp4HSUTSJG7gl5IURQiTvnABzhFW4w
To use the key, pass it as `--key` or `-k`:
{h}${rt} {bin} encrypt \"foo\" --key hNbaua5cGlUNsEp4HSUTSJG7gl5IURQiTvnABzhFW4w
Q0gyMAGSwlWJdALzAAAAE448viN3l+rwa7W4RdkRI0V/VckAAAAA
Or as an environment variable (but `--key` has precedence):
{h}${rt} export {key_env_var}=hNbaua5cGlUNsEp4HSUTSJG7gl5IURQiTvnABzhFW4w
{h}${rt} {bin} encrypt \"foo\"
Q0gyMAGSwlWJdALzAAAAE448viN3l+rwa7W4RdkRI0V/VckAAAAA
The key can also be the name of a file that contains a key:
{h}${rt} echo hNbaua5cGlUNsEp4HSUTSJG7gl5IURQiTvnABzhFW4w > /secrets/{bin}.key
{h}${rt} {bin} decrypt --key /secrets/{bin}.key Q0gyMAGSwlWJdALzAAAAE448viN3l+rwa7W4RdkRI0V/VckAAAAA
foo
To set a key permanently, the recommended solution is to point the
environment variable to a file:
{h}${rt} echo hNbaua5cGlUNsEp4HSUTSJG7gl5IURQiTvnABzhFW4w > ~/.{bin}.key
{h}${rt} echo '{key_env_var}=\"$HOME/.{bin}.key\"' >> ~/.bashrc
Message:
The message can be passed on the command line:
{h}${rt} {bin} encrypt \"bar\"
Q0gyMAHPNRsLieAOAAAAE/ssTCh2zCm73t+aQf9aKNepgPkAAAAA
Or from a file:
{h}${rt} {bin} encrypt --file bar.txt
Q0gyMAHPNRsLieAOAAAAE/ssTCh2zCm73t+aQf9aKNepgPkAAAAA
Or via `stdin` (but the command line has precedence):
{h}${rt} cat bar.txt | {bin} encrypt
Q0gyMAHPNRsLieAOAAAAE/ssTCh2zCm73t+aQf9aKNepgPkAAAAA
By definition, you can round-trip it:
{h}${rt} {bin} encrypt \"hello, world\" -o encrypted.txt
{h}${rt} {bin} decrypt -f encrypted.txt
hello, world
Raw I/O:
If you do not want base64 encoding, you can pass the `--raw` or `-r`
flag. This makes sense for larger files for which you don't want the
~33% size overhead of base64.
{h}${rt} {bin} encrypt --raw \"hello, world\" > hello.enc
{h}${rt} cat hello.enc | {bin} decrypt --raw
hello, world
Compression:
BYOC. {package} does not provide built-in compression, but you can
bring your own:
{h}${rt} gzip -c cat.gif | {bin} encrypt -r > out.enc
{h}${rt} {bin} decrypt -r -f out.enc | gunzip > cat.gif
If you need to compress and encrypt multiple files or directories,
consider `tar`ing them:
{h}${rt} tar -czf - cat.gif more-gifs/ | {bin} encrypt -r > out.enc
{h}${rt} {bin} decrypt -r -f out.enc | tar -xzf -
It makes sense to combine compression with `--raw` to get the smallest
file size possible.
",
help = short_help_message(),
bin = env!("CARGO_BIN_NAME"),
package = env!("CARGO_PKG_NAME"),
key_env_var = cli::KEY_ENV_VAR,
h = ui::Color::maybe_color(ui::color::HIGHLIGHT),
u = ui::Color::maybe_color(ui::color::UNDERLINE),
rt = ui::Color::maybe_color(ui::color::RESET),
));
}
fn version() {
println!("{} {}", env!("CARGO_PKG_NAME"), env!("CARGO_PKG_VERSION"));
}