// Copyright (c) 2012 The Chromium Authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. // Portions of this code based on Mozilla: // (netwerk/cookie/src/nsCookieService.cpp) /* ***** BEGIN LICENSE BLOCK ***** * Version: MPL 1.1/GPL 2.0/LGPL 2.1 * * The contents of this file are subject to the Mozilla Public License Version * 1.1 (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * http://www.mozilla.org/MPL/ * * Software distributed under the License is distributed on an "AS IS" basis, * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License * for the specific language governing rights and limitations under the * License. * * The Original Code is mozilla.org code. * * The Initial Developer of the Original Code is * Netscape Communications Corporation. * Portions created by the Initial Developer are Copyright (C) 2003 * the Initial Developer. All Rights Reserved. * * Contributor(s): * Daniel Witte (dwitte@stanford.edu) * Michiel van Leeuwen (mvl@exedo.nl) * * Alternatively, the contents of this file may be used under the terms of * either the GNU General Public License Version 2 or later (the "GPL"), or * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"), * in which case the provisions of the GPL or the LGPL are applicable instead * of those above. If you wish to allow use of your version of this file only * under the terms of either the GPL or the LGPL, and not to allow others to * use your version of this file under the terms of the MPL, indicate your * decision by deleting the provisions above and replace them with the notice * and other provisions required by the GPL or the LGPL. If you do not delete * the provisions above, a recipient may use your version of this file under * the terms of any one of the MPL, the GPL or the LGPL. * * ***** END LICENSE BLOCK ***** */ #include "net/cookies/canonical_cookie.h" #include "base/format_macros.h" #include "base/logging.h" #include "base/metrics/histogram_macros.h" #include "base/strings/string_util.h" #include "base/strings/stringprintf.h" #include "net/base/url_util.h" #include "net/cookies/cookie_util.h" #include "net/cookies/parsed_cookie.h" #include "url/gurl.h" #include "url/url_canon.h" #include "url/url_util.h" using base::Time; using base::TimeDelta; namespace net { namespace { // Determine the cookie domain to use for setting the specified cookie. bool GetCookieDomain(const GURL& url, const ParsedCookie& pc, std::string* result) { std::string domain_string; if (pc.HasDomain()) domain_string = pc.Domain(); return cookie_util::GetCookieDomainWithString(url, domain_string, result); } // Compares cookies using name, domain and path, so that "equivalent" cookies // (per RFC 2965) are equal to each other. int PartialCookieOrdering(const CanonicalCookie& a, const CanonicalCookie& b) { int diff = a.Name().compare(b.Name()); if (diff != 0) return diff; diff = a.Domain().compare(b.Domain()); if (diff != 0) return diff; return a.Path().compare(b.Path()); } } // namespace // Keep defaults here in sync with content/public/common/cookie_manager.mojom. CanonicalCookie::CanonicalCookie() : secure_(false), httponly_(false), same_site_(CookieSameSite::NO_RESTRICTION), priority_(COOKIE_PRIORITY_MEDIUM) {} CanonicalCookie::CanonicalCookie(const CanonicalCookie& other) = default; CanonicalCookie::CanonicalCookie(const std::string& name, const std::string& value, const std::string& domain, const std::string& path, const base::Time& creation, const base::Time& expiration, const base::Time& last_access, bool secure, bool httponly, CookieSameSite same_site, CookiePriority priority) : name_(name), value_(value), domain_(domain), path_(path), creation_date_(creation), expiry_date_(expiration), last_access_date_(last_access), secure_(secure), httponly_(httponly), same_site_(same_site), priority_(priority) {} CanonicalCookie::~CanonicalCookie() = default; // static std::string CanonicalCookie::CanonPathWithString( const GURL& url, const std::string& path_string) { // The RFC says the path should be a prefix of the current URL path. // However, Mozilla allows you to set any path for compatibility with // broken websites. We unfortunately will mimic this behavior. We try // to be generous and accept cookies with an invalid path attribute, and // default the path to something reasonable. // The path was supplied in the cookie, we'll take it. if (!path_string.empty() && path_string[0] == '/') return path_string; // The path was not supplied in the cookie or invalid, we will default // to the current URL path. // """Defaults to the path of the request URL that generated the // Set-Cookie response, up to, but not including, the // right-most /.""" // How would this work for a cookie on /? We will include it then. const std::string& url_path = url.path(); size_t idx = url_path.find_last_of('/'); // The cookie path was invalid or a single '/'. if (idx == 0 || idx == std::string::npos) return std::string("/"); // Return up to the rightmost '/'. return url_path.substr(0, idx); } // static Time CanonicalCookie::CanonExpiration(const ParsedCookie& pc, const Time& current, const Time& server_time) { // First, try the Max-Age attribute. uint64_t max_age = 0; if (pc.HasMaxAge() && #ifdef COMPILER_MSVC sscanf_s( #else sscanf( #endif pc.MaxAge().c_str(), " %" PRIu64, &max_age) == 1) { return current + TimeDelta::FromSeconds(max_age); } // Try the Expires attribute. if (pc.HasExpires() && !pc.Expires().empty()) { // Adjust for clock skew between server and host. base::Time parsed_expiry = cookie_util::ParseCookieExpirationTime(pc.Expires()); if (!parsed_expiry.is_null()) return parsed_expiry + (current - server_time); } // Invalid or no expiration, persistent cookie. return Time(); } // static std::unique_ptr CanonicalCookie::Create( const GURL& url, const std::string& cookie_line, const base::Time& creation_time, const CookieOptions& options) { ParsedCookie parsed_cookie(cookie_line); if (!parsed_cookie.IsValid()) { VLOG(net::cookie_util::kVlogSetCookies) << "WARNING: Couldn't parse cookie"; return nullptr; } if (options.exclude_httponly() && parsed_cookie.IsHttpOnly()) { VLOG(net::cookie_util::kVlogSetCookies) << "Create() is not creating a httponly cookie"; return nullptr; } std::string cookie_domain; if (!GetCookieDomain(url, parsed_cookie, &cookie_domain)) { VLOG(net::cookie_util::kVlogSetCookies) << "Create() failed to get a cookie domain"; return nullptr; } // Per 3.2.1 of "Deprecate modification of 'secure' cookies from non-secure // origins", if the cookie's "secure-only-flag" is "true" and the requesting // URL does not have a secure scheme, the cookie should be thrown away. // https://tools.ietf.org/html/draft-ietf-httpbis-cookie-alone if (parsed_cookie.IsSecure() && !url.SchemeIsCryptographic()) { VLOG(net::cookie_util::kVlogSetCookies) << "Create() is trying to create a secure cookie from an insecure URL"; return nullptr; } std::string cookie_path = CanonPathWithString( url, parsed_cookie.HasPath() ? parsed_cookie.Path() : std::string()); Time server_time(creation_time); if (options.has_server_time()) server_time = options.server_time(); DCHECK(!creation_time.is_null()); Time cookie_expires = CanonicalCookie::CanonExpiration(parsed_cookie, creation_time, server_time); CookiePrefix prefix = GetCookiePrefix(parsed_cookie.Name()); bool is_cookie_valid = IsCookiePrefixValid(prefix, url, parsed_cookie); RecordCookiePrefixMetrics(prefix, is_cookie_valid); if (!is_cookie_valid) { VLOG(net::cookie_util::kVlogSetCookies) << "Create() failed because the cookie violated prefix rules."; return nullptr; } std::unique_ptr cc(std::make_unique( parsed_cookie.Name(), parsed_cookie.Value(), cookie_domain, cookie_path, creation_time, cookie_expires, creation_time, parsed_cookie.IsSecure(), parsed_cookie.IsHttpOnly(), parsed_cookie.SameSite(), parsed_cookie.Priority())); DCHECK(cc->IsCanonical()); return cc; } // static std::unique_ptr CanonicalCookie::CreateSanitizedCookie( const GURL& url, const std::string& name, const std::string& value, const std::string& domain, const std::string& path, base::Time creation_time, base::Time expiration_time, base::Time last_access_time, bool secure, bool http_only, CookieSameSite same_site, CookiePriority priority) { // Validate consistency of passed arguments. if (ParsedCookie::ParseTokenString(name) != name || ParsedCookie::ParseValueString(value) != value || ParsedCookie::ParseValueString(domain) != domain || ParsedCookie::ParseValueString(path) != path) { return nullptr; } std::string cookie_domain; if (!cookie_util::GetCookieDomainWithString(url, domain, &cookie_domain)) return nullptr; if (secure && !url.SchemeIsCryptographic()) return nullptr; std::string cookie_path = CanonicalCookie::CanonPathWithString(url, path); if (!path.empty() && cookie_path != path) return nullptr; if (!last_access_time.is_null() && creation_time.is_null()) return nullptr; // Canonicalize path again to make sure it escapes characters as needed. url::Component path_component(0, cookie_path.length()); url::RawCanonOutputT canon_path; url::Component canon_path_component; url::CanonicalizePath(cookie_path.data(), path_component, &canon_path, &canon_path_component); cookie_path = std::string(canon_path.data() + canon_path_component.begin, canon_path_component.len); std::unique_ptr cc(std::make_unique( name, value, cookie_domain, cookie_path, creation_time, expiration_time, last_access_time, secure, http_only, same_site, priority)); DCHECK(cc->IsCanonical()); return cc; } bool CanonicalCookie::IsEquivalentForSecureCookieMatching( const CanonicalCookie& ecc) const { return (name_ == ecc.Name() && (ecc.IsDomainMatch(DomainWithoutDot()) || IsDomainMatch(ecc.DomainWithoutDot())) && ecc.IsOnPath(Path())); } bool CanonicalCookie::IsOnPath(const std::string& url_path) const { // A zero length would be unsafe for our trailing '/' checks, and // would also make no sense for our prefix match. The code that // creates a CanonicalCookie should make sure the path is never zero length, // but we double check anyway. if (path_.empty()) return false; // The Mozilla code broke this into three cases, based on if the cookie path // was longer, the same length, or shorter than the length of the url path. // I think the approach below is simpler. // Make sure the cookie path is a prefix of the url path. If the url path is // shorter than the cookie path, then the cookie path can't be a prefix. if (!base::StartsWith(url_path, path_, base::CompareCase::SENSITIVE)) return false; // |url_path| is >= |path_|, and |path_| is a prefix of |url_path|. If they // are the are the same length then they are identical, otherwise need an // additional check: // In order to avoid in correctly matching a cookie path of /blah // with a request path of '/blahblah/', we need to make sure that either // the cookie path ends in a trailing '/', or that we prefix up to a '/' // in the url path. Since we know that the url path length is greater // than the cookie path length, it's safe to index one byte past. if (path_.length() != url_path.length() && path_.back() != '/' && url_path[path_.length()] != '/') { return false; } return true; } bool CanonicalCookie::IsDomainMatch(const std::string& host) const { return cookie_util::IsDomainMatch(domain_, host); } bool CanonicalCookie::IncludeForRequestURL(const GURL& url, const CookieOptions& options) const { // Filter out HttpOnly cookies, per options. if (options.exclude_httponly() && IsHttpOnly()) return false; // Secure cookies should not be included in requests for URLs with an // insecure scheme. if (IsSecure() && !url.SchemeIsCryptographic()) return false; // Don't include cookies for requests that don't apply to the cookie domain. if (!IsDomainMatch(url.host())) return false; // Don't include cookies for requests with a url path that does not path // match the cookie-path. if (!IsOnPath(url.path())) return false; // Don't include same-site cookies for cross-site requests. switch (SameSite()) { case CookieSameSite::STRICT_MODE: if (options.same_site_cookie_mode() != CookieOptions::SameSiteCookieMode::INCLUDE_STRICT_AND_LAX) { return false; } break; case CookieSameSite::LAX_MODE: if (options.same_site_cookie_mode() == CookieOptions::SameSiteCookieMode::DO_NOT_INCLUDE) { return false; } break; default: break; } return true; } std::string CanonicalCookie::DebugString() const { return base::StringPrintf( "name: %s value: %s domain: %s path: %s creation: %" PRId64, name_.c_str(), value_.c_str(), domain_.c_str(), path_.c_str(), static_cast(creation_date_.ToTimeT())); } bool CanonicalCookie::PartialCompare(const CanonicalCookie& other) const { return PartialCookieOrdering(*this, other) < 0; } bool CanonicalCookie::FullCompare(const CanonicalCookie& other) const { // Do the partial comparison first. int diff = PartialCookieOrdering(*this, other); if (diff != 0) return diff < 0; DCHECK(IsEquivalent(other)); // Compare other fields. diff = Value().compare(other.Value()); if (diff != 0) return diff < 0; if (CreationDate() != other.CreationDate()) return CreationDate() < other.CreationDate(); if (ExpiryDate() != other.ExpiryDate()) return ExpiryDate() < other.ExpiryDate(); if (LastAccessDate() != other.LastAccessDate()) return LastAccessDate() < other.LastAccessDate(); if (IsSecure() != other.IsSecure()) return IsSecure(); if (IsHttpOnly() != other.IsHttpOnly()) return IsHttpOnly(); return Priority() < other.Priority(); } bool CanonicalCookie::IsCanonical() const { // Not checking domain or path against ParsedCookie as it may have // come purely from the URL. if (ParsedCookie::ParseTokenString(name_) != name_ || ParsedCookie::ParseValueString(value_) != value_ || !ParsedCookie::IsValidCookieAttributeValue(name_) || !ParsedCookie::IsValidCookieAttributeValue(value_)) { return false; } if (!last_access_date_.is_null() && creation_date_.is_null()) return false; url::CanonHostInfo canon_host_info; std::string canonical_domain(CanonicalizeHost(domain_, &canon_host_info)); // TODO(rdsmith): This specifically allows for empty domains. The spec // suggests this is invalid (if a domain attribute is empty, the cookie's // domain is set to the canonicalized request host; see // https://tools.ietf.org/html/rfc6265#section-5.3). However, it is // needed for Chrome extension cookies. // See http://crbug.com/730633 for more information. if (canonical_domain != domain_) return false; if (path_.empty() || path_[0] != '/') return false; switch (GetCookiePrefix(name_)) { case COOKIE_PREFIX_HOST: if (!secure_ || path_ != "/" || domain_.empty() || domain_[0] == '.') return false; break; case COOKIE_PREFIX_SECURE: if (!secure_) return false; break; default: break; } return true; } // static std::string CanonicalCookie::BuildCookieLine( const std::vector& cookies) { std::string cookie_line; for (const auto& cookie : cookies) { if (!cookie_line.empty()) cookie_line += "; "; // In Mozilla, if you set a cookie like "AAA", it will have an empty token // and a value of "AAA". When it sends the cookie back, it will send "AAA", // so we need to avoid sending "=AAA" for a blank token value. if (!cookie.Name().empty()) cookie_line += cookie.Name() + "="; cookie_line += cookie.Value(); } return cookie_line; } // static CanonicalCookie::CookiePrefix CanonicalCookie::GetCookiePrefix( const std::string& name) { const char kSecurePrefix[] = "__Secure-"; const char kHostPrefix[] = "__Host-"; if (base::StartsWith(name, kSecurePrefix, base::CompareCase::SENSITIVE)) return CanonicalCookie::COOKIE_PREFIX_SECURE; if (base::StartsWith(name, kHostPrefix, base::CompareCase::SENSITIVE)) return CanonicalCookie::COOKIE_PREFIX_HOST; return CanonicalCookie::COOKIE_PREFIX_NONE; } // static void CanonicalCookie::RecordCookiePrefixMetrics( CanonicalCookie::CookiePrefix prefix, bool is_cookie_valid) { const char kCookiePrefixHistogram[] = "Cookie.CookiePrefix"; const char kCookiePrefixBlockedHistogram[] = "Cookie.CookiePrefixBlocked"; UMA_HISTOGRAM_ENUMERATION(kCookiePrefixHistogram, prefix, CanonicalCookie::COOKIE_PREFIX_LAST); if (!is_cookie_valid) { UMA_HISTOGRAM_ENUMERATION(kCookiePrefixBlockedHistogram, prefix, CanonicalCookie::COOKIE_PREFIX_LAST); } } // Returns true if the cookie does not violate any constraints imposed // by the cookie name's prefix, as described in // https://tools.ietf.org/html/draft-west-cookie-prefixes // // static bool CanonicalCookie::IsCookiePrefixValid(CanonicalCookie::CookiePrefix prefix, const GURL& url, const ParsedCookie& parsed_cookie) { if (prefix == CanonicalCookie::COOKIE_PREFIX_SECURE) return parsed_cookie.IsSecure() && url.SchemeIsCryptographic(); if (prefix == CanonicalCookie::COOKIE_PREFIX_HOST) { return parsed_cookie.IsSecure() && url.SchemeIsCryptographic() && !parsed_cookie.HasDomain() && parsed_cookie.Path() == "/"; } return true; } std::string CanonicalCookie::DomainWithoutDot() const { if (domain_.empty() || domain_[0] != '.') return domain_; return domain_.substr(1); } } // namespace net