f use hostname type

Author: TheBlueMatt

lightning/src/onion_message/dns_resolution.rs

@@ -22,7 +22,7 @@ use crate::ln::msgs::DecodeError;
 use crate::onion_message::messenger::{MessageSendInstructions, Responder, ResponseInstruction};
 use crate::onion_message::packet::OnionMessageContents;
 use crate::prelude::*;
-use crate::util::ser::{Readable, ReadableArgs, Writeable, Writer};
+use crate::util::ser::{Hostname, Readable, ReadableArgs, Writeable, Writer};
 
 /// A handler for an [`OnionMessage`] containing a DNS(SEC) query or a DNSSEC proof
 ///
@@ -99,29 +99,16 @@ impl Writeable for DNSResolverMessage {
 	}
 }
 
-fn read_byte_len_ascii_string<R: io::Read>(buffer: &mut R) -> Result<String, DecodeError> {
-	let len: u8 = Readable::read(buffer)?;
-	let mut bytes = [0; 255];
-	buffer.read_exact(&mut bytes[..len as usize])?;
-	if bytes[..len as usize].iter().any(|b| *b < 0x20 || *b > 0x7e) {
-		// If the bytes are not entirely in the printable ASCII range, fail
-		return Err(DecodeError::InvalidValue);
-	}
-	let s =
-		String::from_utf8(bytes[..len as usize].to_vec()).map_err(|_| DecodeError::InvalidValue)?;
-	Ok(s)
-}
-
 impl ReadableArgs<u64> for DNSResolverMessage {
 	fn read<R: io::Read>(r: &mut R, message_type: u64) -> Result<Self, DecodeError> {
 		match message_type {
 			DNSSEC_QUERY_TYPE => {
-				let s = read_byte_len_ascii_string(r)?;
+				let s = Hostname::read(r)?;
 				let name = s.try_into().map_err(|_| DecodeError::InvalidValue)?;
 				Ok(DNSResolverMessage::DNSSECQuery(DNSSECQuery(name)))
 			},
 			DNSSEC_PROOF_TYPE => {
-				let s = read_byte_len_ascii_string(r)?;
+				let s = Hostname::read(r)?;
 				let name = s.try_into().map_err(|_| DecodeError::InvalidValue)?;
 				let proof = Readable::read(r)?;
 				Ok(DNSResolverMessage::DNSSECProof(DNSSECProof { name, proof }))

lightning/src/util/ser.rs

@@ -37,6 +37,9 @@ use bitcoin::hashes::hmac::Hmac;
 use bitcoin::hashes::sha256d::Hash as Sha256dHash;
 use bitcoin::hashes::sha256::Hash as Sha256;
 use bitcoin::hash_types::{Txid, BlockHash};
+
+use dnssec_prover::rr::Name;
+
 use core::time::Duration;
 use crate::chain::ClaimId;
 use crate::ln::msgs::DecodeError;
@@ -1551,6 +1554,13 @@ impl Readable for Hostname {
 	}
 }
 
+impl TryInto<Name> for Hostname {
+	type Error = ();
+	fn try_into(self) -> Result<Name, ()> {
+		Name::try_from(self.0)
+	}
+}
+
 /// This is not exported to bindings users as `Duration`s are simply mapped as ints.
 impl Writeable for Duration {
 	#[inline]