Use bitreq::Url for LSPS5 webhook URLs

Replace the custom LSPS5 URL parser with `bitreq::Url` while keeping the
LSPS5-specific HTTPS and length checks. This reduces bespoke parsing
logic and aligns accepted webhook URLs with the HTTP client's URL
handling.

Co-Authored-By: HAL 9000
Signed-off-by: Elias Rohrer <dev@tnull.de>

Author: tnull

lightning-liquidity/Cargo.toml

@@ -33,6 +33,7 @@ chrono = { version = "0.4", default-features = false, features = ["serde", "allo
 serde = { version = "1.0", default-features = false, features = ["derive", "alloc"] }
 serde_json = { version = "1.0", default-features = false, features = ["alloc"] }
 backtrace = { version = "0.3", optional = true }
+bitreq = { version = "0.3.2", default-features = false }
 
 [dev-dependencies]
 lightning = { version = "0.3.0", path = "../lightning", default-features = false, features = ["_test_utils"] }

lightning-liquidity/src/lsps5/msgs.rs

@@ -876,7 +876,7 @@ mod tests {
 	}
 
 	#[test]
-	fn test_url_security_validation() {
+	fn test_webhook_url_validation() {
 		let urls_that_should_throw = [
 			"test-app",
 			"http://example.com/webhook",
@@ -906,6 +906,16 @@ mod tests {
 		}
 	}
 
+	#[test]
+	fn test_webhook_url_accepts_https_userinfo_and_ipv6() {
+		let userinfo_url =
+			LSPS5WebhookUrl::new("https://user:pass@example.com/webhook".to_string()).unwrap();
+		assert_eq!(userinfo_url.as_str(), "https://user:pass@example.com/webhook");
+
+		let ipv6_url = LSPS5WebhookUrl::new("https://[::1]/webhook".to_string()).unwrap();
+		assert_eq!(ipv6_url.as_str(), "https://[::1]/webhook");
+	}
+
 	#[test]
 	fn test_lsps_url_readable_rejects_http() {
 		use lightning::util::ser::Writeable;

lightning-liquidity/src/lsps5/url_utils.rs

@@ -11,15 +11,28 @@
 
 use super::msgs::LSPS5ProtocolError;
 
+use bitreq::Url;
 use lightning::ln::msgs::DecodeError;
 use lightning::util::ser::{Readable, Writeable};
-use lightning_types::string::UntrustedString;
 
 use alloc::string::String;
+use core::hash::{Hash, Hasher};
 
 /// Represents a parsed URL for LSPS5 webhook notifications.
-#[derive(Debug, Clone, PartialEq, Eq, Hash)]
-pub struct LSPSUrl(UntrustedString);
+#[derive(Debug, Clone, Eq)]
+pub struct LSPSUrl(Url);
+
+impl PartialEq for LSPSUrl {
+	fn eq(&self, other: &Self) -> bool {
+		self.0.as_str() == other.0.as_str()
+	}
+}
+
+impl Hash for LSPSUrl {
+	fn hash<H: Hasher>(&self, state: &mut H) {
+		self.0.as_str().hash(state)
+	}
+}
 
 impl LSPSUrl {
 	/// Parses a URL string into a URL instance.
@@ -30,79 +43,37 @@ impl LSPSUrl {
 	/// # Returns
 	/// A Result containing either the parsed URL or an error message.
 	pub fn parse(url_str: String) -> Result<Self, LSPS5ProtocolError> {
-		if url_str.chars().any(|c| !Self::is_valid_url_char(c)) {
-			return Err(LSPS5ProtocolError::UrlParse);
-		}
+		let url = Url::parse(&url_str).map_err(|_| LSPS5ProtocolError::UrlParse)?;
 
-		let (scheme, remainder) =
-			url_str.split_once("://").ok_or_else(|| LSPS5ProtocolError::UrlParse)?;
-
-		if !scheme.eq_ignore_ascii_case("https") {
+		if url.scheme() != "https" {
 			return Err(LSPS5ProtocolError::UnsupportedProtocol);
 		}
 
-		let host_section =
-			remainder.split(['/', '?', '#']).next().ok_or_else(|| LSPS5ProtocolError::UrlParse)?;
-
-		let host_without_auth = host_section
-			.split('@')
-			.next_back()
-			.filter(|s| !s.is_empty())
-			.ok_or_else(|| LSPS5ProtocolError::UrlParse)?;
-
-		if host_without_auth.is_empty()
-			|| host_without_auth.chars().any(|c| !Self::is_valid_host_char(c))
-		{
-			return Err(LSPS5ProtocolError::UrlParse);
-		}
-
-		match host_without_auth.rsplit_once(':') {
-			Some((hostname, _)) if hostname.is_empty() => return Err(LSPS5ProtocolError::UrlParse),
-			Some((_, port)) => {
-				if !port.is_empty() && port.parse::<u16>().is_err() {
-					return Err(LSPS5ProtocolError::UrlParse);
-				}
-			},
-			None => {},
-		};
-
-		Ok(LSPSUrl(UntrustedString(url_str)))
+		Ok(LSPSUrl(url))
 	}
 
 	/// Returns URL length in bytes.
-	///
-	/// Since [`LSPSUrl::parse`] only accepts ASCII characters, this is equivalent
-	/// to the character count.
 	pub fn url_length(&self) -> usize {
-		self.0 .0.len()
+		self.0.as_str().len()
 	}
 
 	/// Returns the full URL string.
 	pub fn url(&self) -> &str {
-		self.0 .0.as_str()
-	}
-
-	fn is_valid_url_char(c: char) -> bool {
-		c.is_ascii_alphanumeric()
-			|| matches!(c, ':' | '/' | '.' | '@' | '?' | '#' | '%' | '-' | '_' | '&' | '=')
-	}
-
-	fn is_valid_host_char(c: char) -> bool {
-		c.is_ascii_alphanumeric() || matches!(c, '.' | '-' | ':' | '_')
+		self.0.as_str()
 	}
 }
 
 impl Writeable for LSPSUrl {
 	fn write<W: lightning::util::ser::Writer>(
 		&self, writer: &mut W,
 	) -> Result<(), lightning::io::Error> {
-		self.0.write(writer)
+		self.0.as_str().write(writer)
 	}
 }
 
 impl Readable for LSPSUrl {
 	fn read<R: lightning::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
-		let s: UntrustedString = Readable::read(reader)?;
-		Self::parse(s.0).map_err(|_| DecodeError::InvalidValue)
+		let s: String = Readable::read(reader)?;
+		Self::parse(s).map_err(|_| DecodeError::InvalidValue)
 	}
 }

lightning/src/util/ser.rs

@@ -1631,6 +1631,13 @@ impl Readable for () {
 }
 
 impl Writeable for String {
+	#[inline]
+	fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
+		self.as_str().write(w)
+	}
+}
+
+impl Writeable for &str {
 	#[inline]
 	fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
 		CollectionLength(self.len() as u64).write(w)?;
@@ -1797,6 +1804,12 @@ mod tests {
 		assert_eq!(Hostname::read(&mut buf.as_slice()).unwrap().as_str(), "test");
 	}
 
+	#[test]
+	fn str_serialization_matches_string() {
+		let s = "test";
+		assert_eq!(s.encode(), s.to_string().encode());
+	}
+
 	#[test]
 	/// Taproot will likely fill legacy signature fields with all 0s.
 	/// This test ensures that doing so won't break serialization.