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International Domain Names (IDN) support (closes #207)

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This commit is contained in:
Maurus Decimus
2026-06-20 09:02:26 +02:00
parent 52a938297b
commit 0958d97925
14 changed files with 201 additions and 26 deletions
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1
crates/utils/Cargo.toml
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@@ -31,6 +31,7 @@ blake3 = "1.3.3"
http-body-util = "0.1.0"
form_urlencoded = "1.1.0"
psl = "2"
idna = "1.0"
quick_cache = "0.6.9"
fast-float = "0.2.0"
rkyv = { version = "0.8.10", features = ["little_endian"] }

145
crates/utils/src/lib.rs
View File

@@ -26,6 +26,7 @@ use futures::StreamExt;
pub use reqwest::Client;
use reqwest::Response;
pub use reqwest::header::HeaderMap;
use std::borrow::Cow;
use std::fmt::Write;
pub trait HttpLimitResponse: Sync + Send {
@@ -145,27 +146,42 @@ pub async fn wait_for_shutdown() {
}
pub trait DomainPart {
fn to_lowercase_domain(&self) -> String;
fn to_lowercase_address(&self, lower_local: bool) -> String;
fn domain_part(&self) -> &str;
fn try_domain_part(&self) -> Option<&str>;
fn try_local_part(&self) -> Option<&str>;
fn to_ascii_domain(&self) -> Option<Cow<'_, str>>;
}
impl<T: AsRef<str>> DomainPart for T {
fn to_lowercase_domain(&self) -> String {
fn to_lowercase_address(&self, lower_local: bool) -> String {
let address = self.as_ref();
if let Some((local, domain)) = address.rsplit_once('@') {
let mut address = String::with_capacity(address.len());
address.push_str(local);
address.push('@');
for ch in domain.chars() {
for ch in ch.to_lowercase() {
address.push(ch);
if lower_local {
for ch in local.chars() {
for ch in ch.to_lowercase() {
address.push(ch);
}
}
} else {
address.push_str(local);
}
address.push('@');
if domain.is_ascii() {
for ch in domain.chars() {
for ch in ch.to_lowercase() {
address.push(ch);
}
}
} else {
let domain =
idna::domain_to_ascii(domain).unwrap_or_else(|_| domain.to_lowercase());
address.push_str(&domain);
}
address
} else {
address.to_string()
address.to_lowercase()
}
}
@@ -186,6 +202,17 @@ impl<T: AsRef<str>> DomainPart for T {
.map(|(_, d)| d)
.unwrap_or_default()
}
#[inline(always)]
fn to_ascii_domain(&self) -> Option<Cow<'_, str>> {
let domain = self.as_ref();
if domain.is_ascii() {
Some(Cow::Borrowed(domain))
} else {
idna::domain_to_ascii(domain).ok().map(Cow::Owned)
}
}
}
pub trait HexEncode {
@@ -253,6 +280,8 @@ pub fn sanitize_email(email: &str) -> Option<String> {
}
last_ch = NIL_CHAR;
let domain_start = result.len();
let mut domain_is_ascii = true;
for ch in chars {
match ch {
@@ -264,6 +293,9 @@ pub fn sanitize_email(email: &str) -> Option<String> {
}
' ' | '\x09'..='\x0d' => continue,
_ => {
if !ch.is_ascii() {
domain_is_ascii = false;
}
if ch.is_uppercase() {
for ch in ch.to_lowercase() {
result.push(ch);
@@ -279,10 +311,20 @@ pub fn sanitize_email(email: &str) -> Option<String> {
last_ch = ch;
}
if last_ch.is_alphanumeric() && is_valid_domain(&result) {
Some(result)
if !last_ch.is_alphanumeric() {
return None;
}
if domain_is_ascii {
is_valid_domain(&result[domain_start..]).then_some(result)
} else {
None
let domain = idna::domain_to_ascii(&result[domain_start..]).ok()?;
if !is_valid_domain(&domain) {
return None;
}
result.truncate(domain_start);
result.push_str(&domain);
Some(result)
}
}
@@ -330,6 +372,7 @@ pub fn sanitize_domain(domain: &str) -> Option<String> {
let mut result = String::with_capacity(domain.len());
let mut found_dot = false;
let mut last_ch = char::from(0);
let mut is_ascii = true;
for ch in domain.chars() {
if !ch.is_whitespace() {
@@ -338,6 +381,8 @@ pub fn sanitize_domain(domain: &str) -> Option<String> {
if !(last_ch.is_alphanumeric() || last_ch == '-' || last_ch == '_') {
return None;
}
} else if !ch.is_ascii() {
is_ascii = false;
}
last_ch = ch;
for ch in ch.to_lowercase() {
@@ -346,10 +391,15 @@ pub fn sanitize_domain(domain: &str) -> Option<String> {
}
}
if found_dot && last_ch != '.' && is_valid_domain(&result) {
Some(result)
if !(found_dot && last_ch != '.') {
return None;
}
if is_ascii {
is_valid_domain(&result).then_some(result)
} else {
None
let domain = idna::domain_to_ascii(&result).ok()?;
is_valid_domain(&domain).then_some(domain)
}
}
@@ -372,3 +422,70 @@ pub fn is_valid_domain(domain: &str) -> bool {
.rsplit_once('.')
.is_some_and(|(_, tld)| RESERVED_TLDS.contains(&tld))
}
#[cfg(test)]
mod tests {
use crate::DomainPart;
use super::{sanitize_domain, sanitize_email};
#[test]
fn idn_domains_canonicalize_to_a_label() {
assert_eq!(
sanitize_domain("straß6.de").as_deref(),
Some("xn--stra6-oqa.de")
);
assert_eq!(
sanitize_domain("STRASS.straß6.DE").as_deref(),
Some("strass.xn--stra6-oqa.de")
);
assert_eq!(
sanitize_domain("münchen.de").as_deref(),
Some("xn--mnchen-3ya.de")
);
}
#[test]
fn a_label_and_ascii_domains_are_idempotent() {
assert_eq!(
sanitize_domain("xn--stra6-oqa.de").as_deref(),
Some("xn--stra6-oqa.de")
);
assert_eq!(
sanitize_domain(&sanitize_domain("straß6.de").unwrap()).as_deref(),
Some("xn--stra6-oqa.de")
);
assert_eq!(
sanitize_domain("Example.COM").as_deref(),
Some("example.com")
);
}
#[test]
fn email_domain_part_canonicalizes_local_part_preserved() {
assert_eq!(
sanitize_email("cornelius_strauss@straß6.de").as_deref(),
Some("cornelius_strauss@xn--stra6-oqa.de")
);
assert_eq!(
sanitize_email("Foo.Bar@münchen.de").as_deref(),
Some("foo.bar@xn--mnchen-3ya.de")
);
assert_eq!(
sanitize_email("user@example.com").as_deref(),
Some("user@example.com")
);
}
#[test]
fn to_ascii_domain_borrows_ascii_owns_idn() {
assert!(matches!(
"example.com".to_ascii_domain(),
Some(std::borrow::Cow::Borrowed(_))
));
assert!(matches!(
"straß6.de".to_ascii_domain(),
Some(std::borrow::Cow::Owned(_))
));
}
}