servo/components/net/cookie.rs
Kingsley Yung 464d71ecfc
Implement cookie expiry date parsing algorithm (#37715)
The cookie-rs library parses the cookie expiry date based on the format
from RFC 2616 (for HTTP/1.1), which is stricter than the format from RFC
6265 (for HTTP cookie).

This patch implements the cookie expiry date algorithm from RFC 6265.
When Cookie::parse fails in parsing the expiry date, we try to parse the
expiry again with this algorithm, to provide extra compatibility with
legacy systems.

Testing: Pass a WPT test that was expected to fail before, and add a
unit test.
Fixes: #36452

---------

Signed-off-by: Kingsley Yung <kingsley@kkoyung.dev>
2025-07-11 05:18:11 +00:00

604 lines
25 KiB
Rust

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at https://mozilla.org/MPL/2.0/. */
//! Implementation of cookie creation and matching as specified by
//! <http://tools.ietf.org/html/rfc6265>
use std::borrow::ToOwned;
use std::net::{Ipv4Addr, Ipv6Addr};
use std::time::SystemTime;
use cookie::Cookie;
use net_traits::CookieSource;
use net_traits::pub_domains::is_pub_domain;
use nom::IResult;
use nom::branch::alt;
use nom::bytes::complete::{tag, tag_no_case, take, take_while_m_n};
use nom::combinator::{opt, recognize};
use nom::multi::{many0, many1, separated_list1};
use nom::sequence::{delimited, preceded, terminated, tuple};
use serde::{Deserialize, Serialize};
use servo_url::ServoUrl;
use time::{Date, Month, OffsetDateTime, Time};
/// A stored cookie that wraps the definition in cookie-rs. This is used to implement
/// various behaviours defined in the spec that rely on an associated request URL,
/// which cookie-rs and hyper's header parsing do not support.
#[derive(Clone, Debug, Deserialize, Serialize)]
pub struct ServoCookie {
#[serde(
deserialize_with = "hyper_serde::deserialize",
serialize_with = "hyper_serde::serialize"
)]
pub cookie: Cookie<'static>,
pub host_only: bool,
pub persistent: bool,
pub creation_time: SystemTime,
pub last_access: SystemTime,
pub expiry_time: Option<SystemTime>,
}
impl ServoCookie {
pub fn from_cookie_string(
cookie_str: String,
request: &ServoUrl,
source: CookieSource,
) -> Option<ServoCookie> {
let mut cookie = Cookie::parse(cookie_str.clone()).ok()?;
// Cookie::parse uses RFC 2616 <http://tools.ietf.org/html/rfc2616#section-3.3.1> to parse
// cookie expiry date. If it fails to parse the expiry date, try to parse again with
// less strict algorithm from RFC6265.
// TODO: We can remove this code and the ServoCookie::parse_date function if cookie-rs
// library fixes this upstream.
if cookie.expires_datetime().is_none() {
let expiry_date_str = cookie_str
.split(';')
.filter_map(|key_value| {
key_value
.find('=')
.map(|i| (key_value[..i].trim(), key_value[(i + 1)..].trim()))
})
.find_map(|(key, value)| key.eq_ignore_ascii_case("expires").then_some(value));
if let Some(date_str) = expiry_date_str {
cookie.set_expires(Self::parse_date(date_str));
}
}
ServoCookie::new_wrapped(cookie, request, source)
}
/// Steps 6-22 from <https://www.ietf.org/archive/id/draft-ietf-httpbis-rfc6265bis-15.html#name-storage-model>
pub fn new_wrapped(
mut cookie: Cookie<'static>,
request: &ServoUrl,
source: CookieSource,
) -> Option<ServoCookie> {
let persistent;
let expiry_time;
// Step 6. If the cookie-attribute-list contains an attribute with an attribute-name of "Max-Age":
if let Some(max_age) = cookie.max_age() {
// 1. Set the cookie's persistent-flag to true.
persistent = true;
// 2. Set the cookie's expiry-time to attribute-value of the last
// attribute in the cookie-attribute-list with an attribute-name of "Max-Age".
expiry_time = Some(SystemTime::now() + max_age);
}
// Otherwise, if the cookie-attribute-list contains an attribute with an attribute-name of "Expires":
else if let Some(date_time) = cookie.expires_datetime() {
// 1. Set the cookie's persistent-flag to true.
persistent = true;
// 2. Set the cookie's expiry-time to attribute-value of the last attribute in the
// cookie-attribute-list with an attribute-name of "Expires".
expiry_time = Some(date_time.into());
}
// Otherwise:
else {
// 1. Set the cookie's persistent-flag to false.
persistent = false;
// 2. Set the cookie's expiry-time to the latest representable date.
expiry_time = None;
}
let url_host = request.host_str().unwrap_or("").to_owned();
// Step 7. If the cookie-attribute-list contains an attribute with an attribute-name of "Domain":
let mut domain = if let Some(domain) = cookie.domain() {
// 1. Let the domain-attribute be the attribute-value of the last attribute in the
// cookie-attribute-list [..]
// NOTE: This is done by the cookie crate
domain.to_owned()
}
// Otherwise:
else {
// 1. Let the domain-attribute be the empty string.
String::new()
};
// TODO Step 8. If the domain-attribute contains a character that is not in the range of [USASCII] characters,
// abort these steps and ignore the cookie entirely.
// NOTE: (is this done by the cookies crate?)
// Step 9. If the user agent is configured to reject "public suffixes" and the domain-attribute
// is a public suffix:
if is_pub_domain(&domain) {
// 1. If the domain-attribute is identical to the canonicalized request-host:
if domain == url_host {
// 1. Let the domain-attribute be the empty string.
domain = String::new();
}
// Otherwise:
else {
// 1.Abort these steps and ignore the cookie entirely.
return None;
}
}
// Step 10. If the domain-attribute is non-empty:
let host_only;
if !domain.is_empty() {
// 1. If the canonicalized request-host does not domain-match the domain-attribute:
if !ServoCookie::domain_match(&url_host, &domain) {
// 1. Abort these steps and ignore the cookie entirely.
return None;
} else {
// 1. Set the cookie's host-only-flag to false.
host_only = false;
// 2. Set the cookie's domain to the domain-attribute.
cookie.set_domain(domain);
}
}
// Otherwise:
else {
// 1. Set the cookie's host-only-flag to true.
host_only = true;
// 2. Set the cookie's domain to the canonicalized request-host.
cookie.set_domain(url_host);
};
// Step 11. If the cookie-attribute-list contains an attribute with an attribute-name of "Path",
// set the cookie's path to attribute-value of the last attribute in the cookie-attribute-list
// with both an attribute-name of "Path" and an attribute-value whose length is no more than 1024 octets.
// Otherwise, set the cookie's path to the default-path of the request-uri.
let mut has_path_specified = true;
let mut path = cookie
.path()
.unwrap_or_else(|| {
has_path_specified = false;
""
})
.to_owned();
// TODO: Why do we do this?
if !path.starts_with('/') {
path = ServoCookie::default_path(request.path()).to_string();
}
cookie.set_path(path);
// Step 12. If the cookie-attribute-list contains an attribute with an attribute-name of "Secure",
// set the cookie's secure-only-flag to true. Otherwise, set the cookie's secure-only-flag to false.
let secure_only = cookie.secure().unwrap_or(false);
// Step 13. If the request-uri does not denote a "secure" connection (as defined by the user agent),
// and the cookie's secure-only-flag is true, then abort these steps and ignore the cookie entirely.
if secure_only && !request.is_secure_scheme() {
return None;
}
// Step 14. If the cookie-attribute-list contains an attribute with an attribute-name of "HttpOnly",
// set the cookie's http-only-flag to true. Otherwise, set the cookie's http-only-flag to false.
let http_only = cookie.http_only().unwrap_or(false);
// Step 15. If the cookie was received from a "non-HTTP" API and the cookie's
// http-only-flag is true, abort these steps and ignore the cookie entirely.
if http_only && source == CookieSource::NonHTTP {
return None;
}
// TODO: Step 16, Ignore cookies from insecure request uris based on existing cookies
// TODO: Steps 17-19, same-site-flag
// Step 20. If the cookie-name begins with a case-insensitive match for the string "__Secure-",
// abort these steps and ignore the cookie entirely unless the cookie's secure-only-flag is true.
let has_case_insensitive_prefix = |value: &str, prefix: &str| {
value
.get(..prefix.len())
.is_some_and(|p| p.eq_ignore_ascii_case(prefix))
};
if has_case_insensitive_prefix(cookie.name(), "__Secure-") &&
!cookie.secure().unwrap_or(false)
{
return None;
}
// Step 21. If the cookie-name begins with a case-insensitive match for the string "__Host-",
// abort these steps and ignore the cookie entirely unless the cookie meets all the following criteria:
if has_case_insensitive_prefix(cookie.name(), "__Host-") {
// 1. The cookie's secure-only-flag is true.
if !secure_only {
return None;
}
// 2. The cookie's host-only-flag is true.
if !host_only {
return None;
}
// 3. The cookie-attribute-list contains an attribute with an attribute-name of "Path",
// and the cookie's path is /.
#[allow(clippy::nonminimal_bool)]
if !has_path_specified || !cookie.path().is_some_and(|path| path == "/") {
return None;
}
}
// Step 22. If the cookie-name is empty and either of the following conditions are true,
// abort these steps and ignore the cookie entirely:
if cookie.name().is_empty() {
// 1. the cookie-value begins with a case-insensitive match for the string "__Secure-"
if has_case_insensitive_prefix(cookie.value(), "__Secure-") {
return None;
}
// 2. the cookie-value begins with a case-insensitive match for the string "__Host-"
if has_case_insensitive_prefix(cookie.value(), "__Host-") {
return None;
}
}
Some(ServoCookie {
cookie,
host_only,
persistent,
creation_time: SystemTime::now(),
last_access: SystemTime::now(),
expiry_time,
})
}
pub fn touch(&mut self) {
self.last_access = SystemTime::now();
}
pub fn set_expiry_time_in_past(&mut self) {
self.expiry_time = Some(SystemTime::UNIX_EPOCH)
}
/// <http://tools.ietf.org/html/rfc6265#section-5.1.4>
pub fn default_path(request_path: &str) -> &str {
// Step 2
if !request_path.starts_with('/') {
return "/";
}
// Step 3
let rightmost_slash_idx = request_path.rfind('/').unwrap();
if rightmost_slash_idx == 0 {
// There's only one slash; it's the first character
return "/";
}
// Step 4
&request_path[..rightmost_slash_idx]
}
/// <http://tools.ietf.org/html/rfc6265#section-5.1.4>
pub fn path_match(request_path: &str, cookie_path: &str) -> bool {
// A request-path path-matches a given cookie-path if at least one of
// the following conditions holds:
// The cookie-path and the request-path are identical.
request_path == cookie_path ||
(request_path.starts_with(cookie_path) &&
(
// The cookie-path is a prefix of the request-path, and the last
// character of the cookie-path is %x2F ("/").
cookie_path.ends_with('/') ||
// The cookie-path is a prefix of the request-path, and the first
// character of the request-path that is not included in the cookie-
// path is a %x2F ("/") character.
request_path[cookie_path.len()..].starts_with('/')
))
}
/// <http://tools.ietf.org/html/rfc6265#section-5.1.3>
pub fn domain_match(string: &str, domain_string: &str) -> bool {
let string = &string.to_lowercase();
let domain_string = &domain_string.to_lowercase();
string == domain_string ||
(string.ends_with(domain_string) &&
string.as_bytes()[string.len() - domain_string.len() - 1] == b'.' &&
string.parse::<Ipv4Addr>().is_err() &&
string.parse::<Ipv6Addr>().is_err())
}
/// <http://tools.ietf.org/html/rfc6265#section-5.4> step 1
pub fn appropriate_for_url(&self, url: &ServoUrl, source: CookieSource) -> bool {
let domain = url.host_str();
if self.host_only {
if self.cookie.domain() != domain {
return false;
}
} else if let (Some(domain), Some(cookie_domain)) = (domain, &self.cookie.domain()) {
if !ServoCookie::domain_match(domain, cookie_domain) {
return false;
}
}
if let Some(cookie_path) = self.cookie.path() {
if !ServoCookie::path_match(url.path(), cookie_path) {
return false;
}
}
if self.cookie.secure().unwrap_or(false) && !url.is_secure_scheme() {
return false;
}
if self.cookie.http_only().unwrap_or(false) && source == CookieSource::NonHTTP {
return false;
}
true
}
/// <https://www.ietf.org/archive/id/draft-ietf-httpbis-rfc6265bis-20.html#name-dates>
pub fn parse_date(string: &str) -> Option<OffsetDateTime> {
let string_in_bytes = string.as_bytes();
// Helper closures
let parse_ascii_u8 =
|bytes: &[u8]| -> Option<u8> { std::str::from_utf8(bytes).ok()?.parse::<u8>().ok() };
let parse_ascii_i32 =
|bytes: &[u8]| -> Option<i32> { std::str::from_utf8(bytes).ok()?.parse::<i32>().ok() };
// Step 1. Using the grammar below, divide the cookie-date into date-tokens.
// *OCTET
let any_octets = |input| Ok(("".as_bytes(), input));
// delimiter = %x09 / %x20-2F / %x3B-40 / %x5B-60 / %x7B-7E
let delimiter: fn(&[u8]) -> IResult<&[u8], u8> = |input| {
let (input, bytes) = take(1usize)(input)?;
if matches!(bytes[0], 0x09 | 0x20..=0x2F | 0x3B..=0x40 | 0x5B..=0x60 | 0x7B..=0x7E) {
Ok((input, bytes[0]))
} else {
Err(nom::Err::Error(nom::error::Error::new(
input,
nom::error::ErrorKind::Verify,
)))
}
};
// non-delimiter = %x00-08 / %x0A-1F / DIGIT / ":" / ALPHA / %x7F-FF
let non_delimiter: fn(&[u8]) -> IResult<&[u8], u8> = |input| {
let (input, bytes) = take(1usize)(input)?;
if matches!(bytes[0],
0x00..=0x08 | 0x0A..=0x1F | b'0'..=b'9' | b':' | b'A'..=b'Z' | b'a'..=b'z' | 0x7F..=0xFF)
{
Ok((input, bytes[0]))
} else {
Err(nom::Err::Error(nom::error::Error::new(
input,
nom::error::ErrorKind::Verify,
)))
}
};
// non-digit = %x00-2F / %x3A-FF
let non_digit: fn(&[u8]) -> IResult<&[u8], u8> = |input| {
let (input, bytes) = take(1usize)(input)?;
if matches!(bytes[0], 0x00..=0x2F | 0x3A..=0xFF) {
Ok((input, bytes[0]))
} else {
Err(nom::Err::Error(nom::error::Error::new(
input,
nom::error::ErrorKind::Verify,
)))
}
};
// time-field = 1*2DIGIT
let time_field = |input| take_while_m_n(1, 2, |byte: u8| byte.is_ascii_digit())(input);
// hms-time = time-field ":" time-field ":" time-field
let hms_time = |input| {
tuple((
time_field,
preceded(tag(":"), time_field),
preceded(tag(":"), time_field),
))(input)
};
// time = hms-time [ non-digit *OCTET ]
let time = |input| terminated(hms_time, opt(tuple((non_digit, any_octets))))(input);
// year = 2*4DIGIT [ non-digit *OCTET ]
let year = |input| {
terminated(
take_while_m_n(2, 4, |byte: u8| byte.is_ascii_digit()),
opt(tuple((non_digit, any_octets))),
)(input)
};
// month = ( "jan" / "feb" / "mar" / "apr" /
// "may" / "jun" / "jul" / "aug" /
// "sep" / "oct" / "nov" / "dec" ) *OCTET
let month = |input| {
terminated(
alt((
tag_no_case("jan"),
tag_no_case("feb"),
tag_no_case("mar"),
tag_no_case("apr"),
tag_no_case("may"),
tag_no_case("jun"),
tag_no_case("jul"),
tag_no_case("aug"),
tag_no_case("sep"),
tag_no_case("oct"),
tag_no_case("nov"),
tag_no_case("dec"),
)),
any_octets,
)(input)
};
// day-of-month = 1*2DIGIT [ non-digit *OCTET ]
let day_of_month = |input| {
terminated(
take_while_m_n(1, 2, |byte: u8| byte.is_ascii_digit()),
opt(tuple((non_digit, any_octets))),
)(input)
};
// date-token = 1*non-delimiter
let date_token = |input| recognize(many1(non_delimiter))(input);
// date-token-list = date-token *( 1*delimiter date-token )
let date_token_list = |input| separated_list1(delimiter, date_token)(input);
// cookie-date = *delimiter date-token-list *delimiter
let cookie_date =
|input| delimited(many0(delimiter), date_token_list, many0(delimiter))(input);
// Step 2. Process each date-token sequentially in the order the date-tokens appear in the cookie-date:
let mut time_value: Option<(u8, u8, u8)> = None; // Also represents found-time flag.
let mut day_of_month_value: Option<u8> = None; // Also represents found-day-of-month flag.
let mut month_value: Option<Month> = None; // Also represents found-month flag.
let mut year_value: Option<i32> = None; // Also represents found-year flag.
let (_, date_tokens) = cookie_date(string_in_bytes).ok()?;
for date_token in date_tokens {
// Step 2.1. If the found-time flag is not set and the token matches the time production,
if time_value.is_none() {
if let Ok((_, result)) = time(date_token) {
// set the found-time flag and set the hour-value, minute-value, and
// second-value to the numbers denoted by the digits in the date-token,
// respectively.
if let (Some(hour), Some(minute), Some(second)) = (
parse_ascii_u8(result.0),
parse_ascii_u8(result.1),
parse_ascii_u8(result.2),
) {
time_value = Some((hour, minute, second));
}
// Skip the remaining sub-steps and continue to the next date-token.
continue;
}
}
// Step 2.2. If the found-day-of-month flag is not set and the date-token matches the
// day-of-month production,
if day_of_month_value.is_none() {
if let Ok((_, result)) = day_of_month(date_token) {
// set the found-day-of-month flag and set the day-of-month-value to the number
// denoted by the date-token.
day_of_month_value = parse_ascii_u8(result);
// Skip the remaining sub-steps and continue to the next date-token.
continue;
}
}
// Step 2.3. If the found-month flag is not set and the date-token matches the month production,
if month_value.is_none() {
if let Ok((_, result)) = month(date_token) {
// set the found-month flag and set the month-value to the month denoted by the date-token.
month_value = match std::str::from_utf8(result)
.unwrap()
.to_ascii_lowercase()
.as_str()
{
"jan" => Some(Month::January),
"feb" => Some(Month::February),
"mar" => Some(Month::March),
"apr" => Some(Month::April),
"may" => Some(Month::May),
"jun" => Some(Month::June),
"jul" => Some(Month::July),
"aug" => Some(Month::August),
"sep" => Some(Month::September),
"oct" => Some(Month::October),
"nov" => Some(Month::November),
"dec" => Some(Month::December),
_ => None,
};
// Skip the remaining sub-steps and continue to the next date-token.
continue;
}
}
// Step 2.4. If the found-year flag is not set and the date-token matches the year production,
if year_value.is_none() {
if let Ok((_, result)) = year(date_token) {
// set the found-year flag and set the year-value to the number denoted by the date-token.
year_value = parse_ascii_i32(result);
// Skip the remaining sub-steps and continue to the next date-token.
continue;
}
}
}
// Step 3. If the year-value is greater than or equal to 70 and less than or equal to 99,
// increment the year-value by 1900.
if let Some(value) = year_value {
if (70..=99).contains(&value) {
year_value = Some(value + 1900);
}
}
// Step 4. If the year-value is greater than or equal to 0 and less than or equal to 69,
// increment the year-value by 2000.
if let Some(value) = year_value {
if (0..=69).contains(&value) {
year_value = Some(value + 2000);
}
}
// Step 5. Abort these steps and fail to parse the cookie-date if:
// * at least one of the found-day-of-month, found-month, found-year, or found-time flags is not set,
if day_of_month_value.is_none() ||
month_value.is_none() ||
year_value.is_none() ||
time_value.is_none()
{
return None;
}
// * the day-of-month-value is less than 1 or greater than 31,
if let Some(value) = day_of_month_value {
if !(1..=31).contains(&value) {
return None;
}
}
// * the year-value is less than 1601,
if let Some(value) = year_value {
if value < 1601 {
return None;
}
}
// * the hour-value is greater than 23,
// * the minute-value is greater than 59, or
// * the second-value is greater than 59.
if let Some((hour_value, minute_value, second_value)) = time_value {
if hour_value > 23 || minute_value > 59 || second_value > 59 {
return None;
}
}
// Step 6. Let the parsed-cookie-date be the date whose day-of-month, month, year, hour,
// minute, and second (in UTC) are the day-of-month-value, the month-value, the year-value,
// the hour-value, the minute-value, and the second-value, respectively. If no such date
// exists, abort these steps and fail to parse the cookie-date.
let parsed_cookie_date = OffsetDateTime::new_utc(
Date::from_calendar_date(
year_value.unwrap(),
month_value.unwrap(),
day_of_month_value.unwrap(),
)
.ok()?,
Time::from_hms(
time_value.unwrap().0,
time_value.unwrap().1,
time_value.unwrap().2,
)
.ok()?,
);
// Step 7. Return the parsed-cookie-date as the result of this algorithm.
Some(parsed_cookie_date)
}
}