rust-dnsbox/lib/dnsbox-base/src/common_types/name/tests.rs

use bytes::Bytes;
use crate::ser::packet;
use crate::ser::packet::DnsPacketData;
use std::io::Cursor;
use crate::errors::*;

use super::{DnsName, DnsCompressedName, DnsLabelRef, DisplayLabels, DisplayLabelsOptions};

/*
fn deserialize(bytes: &'static [u8]) -> Result<DnsName> {
	let result = packet::deserialize_with(Bytes::from_static(bytes), DnsName::deserialize)?;
	{
		let check_result = packet::deserialize_with(result.clone().encode(), DnsName::deserialize).unwrap();
		assert_eq!(check_result, result);
	}
	Ok(result)
}
*/

fn de_uncompressed(bytes: &'static [u8]) -> Result<DnsName> {
	let result = packet::deserialize_with(Bytes::from_static(bytes), DnsName::deserialize)?;
	assert_eq!(bytes, result.clone().encode());
	Ok(result)
}

fn check_uncompressed_display(bytes: &'static [u8], txt: &str, label_count: u8) {
	let name = de_uncompressed(bytes).unwrap();
	assert_eq!(
		name.labels().count(),
		label_count as usize
	);
	assert_eq!(
		format!("{}", name),
		txt
	);
}

fn check_uncompressed_debug(bytes: &'static [u8], txt: &str) {
	let name = de_uncompressed(bytes).unwrap();
	assert_eq!(
		format!("{:?}", name),
		txt
	);
}

#[test]
fn parse_and_display_name() {
	check_uncompressed_display(
		b"\x07example\x03com\x00",
		"example.com.",
		2,
	);
	check_uncompressed_display(
		b"\x07e!am.l\\\x03com\x00",
		"e\\033am\\.l\\\\.com.",
		2,
	);
	check_uncompressed_debug(
		b"\x07e!am.l\\\x03com\x00",
		r#""e\\033am\\.l\\\\.com.""#,
	);
}

#[test]
fn parse_and_reverse_name() {
	let name = de_uncompressed(b"\x03www\x07example\x03com\x00").unwrap();
	assert_eq!(
		format!(
			"{}",
			DisplayLabels{
				labels: name.labels().rev(),
				options: DisplayLabelsOptions{
					separator: " ",
					trailing: false,
				},
			}
		),
		"com example www"
	);
}

#[test]
fn modifications() {
	let mut name = de_uncompressed(b"\x07example\x03com\x00").unwrap();

	name.push_front(DnsLabelRef::new(b"www").unwrap()).unwrap();
	assert_eq!(
		format!("{}", name),
		"www.example.com."
	);

	name.push_back(DnsLabelRef::new(b"org").unwrap()).unwrap();
	assert_eq!(
		format!("{}", name),
		"www.example.com.org."
	);

	name.pop_front();
	assert_eq!(
		format!("{}", name),
		"example.com.org."
	);

	name.push_front(DnsLabelRef::new(b"mx").unwrap()).unwrap();
	assert_eq!(
		format!("{}", name),
		"mx.example.com.org."
	);
	// the "mx" label should fit into the place "www" used before,
	// make sure the buffer was reused and the name not moved within
	assert_eq!(1, name.label_offsets.label_pos(0));

	name.push_back(DnsLabelRef::new(b"com").unwrap()).unwrap();
	assert_eq!(
		format!("{}", name),
		"mx.example.com.org.com."
	);
}



fn de_compressed(bytes: &'static [u8], offset: usize) -> Result<DnsCompressedName> {
	use bytes::Buf;

	let mut c = Cursor::new(Bytes::from_static(bytes));
	c.set_position(offset as u64);
	let result = DnsPacketData::deserialize(&mut c)?;
	if c.remaining() != 0 {
		failure::bail!("data remaining: {}", c.remaining())
	}
	Ok(result)
}

fn check_compressed_display(bytes: &'static [u8], offset: usize, txt: &str, label_count: u8) {
	let name = de_compressed(bytes, offset).unwrap();
	assert_eq!(
		name.labels().count(),
		label_count as usize
	);
	assert_eq!(
		format!("{}", name),
		txt
	);
}

fn check_compressed_debug(bytes: &'static [u8], offset: usize, txt: &str) {
	let name = de_compressed(bytes, offset).unwrap();
	assert_eq!(
		format!("{:?}", name),
		txt
	);
}

#[test]
fn parse_invalid_compressed_name() {
	de_compressed(b"\x11com\x00\x07example\xc0\x00", 5).unwrap_err();
	de_compressed(b"\x10com\x00\x07example\xc0\x00", 5).unwrap_err();
}

#[test]
fn parse_and_display_compressed_name() {
	check_compressed_display(
		b"\x03com\x00\x07example\xc0\x00", 5,
		"example.com.",
		2,
	);
	check_compressed_display(
		b"\x03com\x00\x07e!am.l\\\xc0\x00", 5,
		"e\\033am\\.l\\\\.com.",
		2,
	);
	check_compressed_debug(
		b"\x03com\x00\x07e!am.l\\\xc0\x00", 5,
		r#""e\\033am\\.l\\\\.com.""#,
	);
	check_compressed_display(
		b"\x03com\x00\x07example\xc0\x00\x03www\xc0\x05", 15,
		"www.example.com.",
		3,
	);
}

#[test]
fn modifications_compressed() {
	let mut name = de_compressed(b"\x03com\x00\x07example\xc0\x00\xc0\x05", 15).unwrap();

	name.push_front(DnsLabelRef::new(b"www").unwrap()).unwrap();
	assert_eq!(
		format!("{}", name),
		"www.example.com."
	);

	name.push_back(DnsLabelRef::new(b"org").unwrap()).unwrap();
	assert_eq!(
		format!("{}", name),
		"www.example.com.org."
	);

	name.pop_front();
	assert_eq!(
		format!("{}", name),
		"example.com.org."
	);

	name.push_front(DnsLabelRef::new(b"mx").unwrap()).unwrap();
	assert_eq!(
		format!("{}", name),
		"mx.example.com.org."
	);
	// the "mx" label should fit into the place "www" used before,
	// make sure the buffer was reused and the name not moved within
	assert_eq!(1, name.label_offsets.label_pos(0));

	name.push_back(DnsLabelRef::new(b"com").unwrap()).unwrap();
	assert_eq!(
		format!("{}", name),
		"mx.example.com.org.com."
	);
}