net/cookies/cookie_util.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "net/cookies/cookie_util.h"
   6
   7 #include <cstdio>
   8 #include <cstdlib>
   9
  10 #include "base/logging.h"
  11 #include "base/strings/string_tokenizer.h"
  12 #include "base/strings/string_util.h"
  13 #include "build/build_config.h"
  14 #include "net/base/net_util.h"
  15 #include "net/base/registry_controlled_domains/registry_controlled_domain.h"
  16 #include "url/gurl.h"
  17
  18 namespace net {
  19 namespace cookie_util {
  20
  21 bool DomainIsHostOnly(const std::string& domain_string) {
  22   return (domain_string.empty() || domain_string[0] != '.');
  23 }
  24
  25 std::string GetEffectiveDomain(const std::string& scheme,
  26                                const std::string& host) {
  27   if (scheme == "http" || scheme == "https") {
  28     return registry_controlled_domains::GetDomainAndRegistry(
  29         host,
  30         registry_controlled_domains::INCLUDE_PRIVATE_REGISTRIES);
  31   }
  32
  33   if (!DomainIsHostOnly(host))
  34     return host.substr(1);
  35   return host;
  36 }
  37
  38 bool GetCookieDomainWithString(const GURL& url,
  39                                const std::string& domain_string,
  40                                std::string* result) {
  41   const std::string url_host(url.host());
  42
  43   // If no domain was specified in the domain string, default to a host cookie.
  44   // We match IE/Firefox in allowing a domain=IPADDR if it matches the url
  45   // ip address hostname exactly.  It should be treated as a host cookie.
  46   if (domain_string.empty() ||
  47       (url.HostIsIPAddress() && url_host == domain_string)) {
  48     *result = url_host;
  49     DCHECK(DomainIsHostOnly(*result));
  50     return true;
  51   }
  52
  53   // Get the normalized domain specified in cookie line.
  54   url::CanonHostInfo ignored;
  55   std::string cookie_domain(CanonicalizeHost(domain_string, &ignored));
  56   if (cookie_domain.empty())
  57     return false;
  58   if (cookie_domain[0] != '.')
  59     cookie_domain = "." + cookie_domain;
  60
  61   // Ensure |url| and |cookie_domain| have the same domain+registry.
  62   const std::string url_scheme(url.scheme());
  63   const std::string url_domain_and_registry(
  64       GetEffectiveDomain(url_scheme, url_host));
  65   if (url_domain_and_registry.empty())
  66     return false;  // IP addresses/intranet hosts can't set domain cookies.
  67   const std::string cookie_domain_and_registry(
  68       GetEffectiveDomain(url_scheme, cookie_domain));
  69   if (url_domain_and_registry != cookie_domain_and_registry)
  70     return false;  // Can't set a cookie on a different domain + registry.
  71
  72   // Ensure |url_host| is |cookie_domain| or one of its subdomains.  Given that
  73   // we know the domain+registry are the same from the above checks, this is
  74   // basically a simple string suffix check.
  75   const bool is_suffix = (url_host.length() < cookie_domain.length()) ?
  76       (cookie_domain != ("." + url_host)) :
  77       (url_host.compare(url_host.length() - cookie_domain.length(),
  78                         cookie_domain.length(), cookie_domain) != 0);
  79   if (is_suffix)
  80     return false;
  81
  82   *result = cookie_domain;
  83   return true;
  84 }
  85
  86 // Parse a cookie expiration time.  We try to be lenient, but we need to
  87 // assume some order to distinguish the fields.  The basic rules:
  88 //  - The month name must be present and prefix the first 3 letters of the
  89 //    full month name (jan for January, jun for June).
  90 //  - If the year is <= 2 digits, it must occur after the day of month.
  91 //  - The time must be of the format hh:mm:ss.
  92 // An average cookie expiration will look something like this:
  93 //   Sat, 15-Apr-17 21:01:22 GMT
  94 base::Time ParseCookieTime(const std::string& time_string) {
  95   static const char* kMonths[] = { "jan", "feb", "mar", "apr", "may", "jun",
  96                                    "jul", "aug", "sep", "oct", "nov", "dec" };
  97   static const int kMonthsLen = arraysize(kMonths);
  98   // We want to be pretty liberal, and support most non-ascii and non-digit
  99   // characters as a delimiter.  We can't treat : as a delimiter, because it
 100   // is the delimiter for hh:mm:ss, and we want to keep this field together.
 101   // We make sure to include - and +, since they could prefix numbers.
 102   // If the cookie attribute came in in quotes (ex expires="XXX"), the quotes
 103   // will be preserved, and we will get them here.  So we make sure to include
 104   // quote characters, and also \ for anything that was internally escaped.
 105   static const char* kDelimiters = "\t !\"#$%&'()*+,-./;<=>?@[\\]^_`{|}~";
 106
 107   base::Time::Exploded exploded = {0};
 108
 109   base::StringTokenizer tokenizer(time_string, kDelimiters);
 110
 111   bool found_day_of_month = false;
 112   bool found_month = false;
 113   bool found_time = false;
 114   bool found_year = false;
 115
 116   while (tokenizer.GetNext()) {
 117     const std::string token = tokenizer.token();
 118     DCHECK(!token.empty());
 119     bool numerical = IsAsciiDigit(token[0]);
 120
 121     // String field
 122     if (!numerical) {
 123       if (!found_month) {
 124         for (int i = 0; i < kMonthsLen; ++i) {
 125           // Match prefix, so we could match January, etc
 126           if (base::strncasecmp(token.c_str(), kMonths[i], 3) == 0) {
 127             exploded.month = i + 1;
 128             found_month = true;
 129             break;
 130           }
 131         }
 132       } else {
 133         // If we've gotten here, it means we've already found and parsed our
 134         // month, and we have another string, which we would expect to be the
 135         // the time zone name.  According to the RFC and my experiments with
 136         // how sites format their expirations, we don't have much of a reason
 137         // to support timezones.  We don't want to ever barf on user input,
 138         // but this DCHECK should pass for well-formed data.
 139         // DCHECK(token == "GMT");
 140       }
 141     // Numeric field w/ a colon
 142     } else if (token.find(':') != std::string::npos) {
 143       if (!found_time &&
 144 #ifdef COMPILER_MSVC
 145           sscanf_s(
 146 #else
 147           sscanf(
 148 #endif
 149                  token.c_str(), "%2u:%2u:%2u", &exploded.hour,
 150                  &exploded.minute, &exploded.second) == 3) {
 151         found_time = true;
 152       } else {
 153         // We should only ever encounter one time-like thing.  If we're here,
 154         // it means we've found a second, which shouldn't happen.  We keep
 155         // the first.  This check should be ok for well-formed input:
 156         // NOTREACHED();
 157       }
 158     // Numeric field
 159     } else {
 160       // Overflow with atoi() is unspecified, so we enforce a max length.
 161       if (!found_day_of_month && token.length() <= 2) {
 162         exploded.day_of_month = atoi(token.c_str());
 163         found_day_of_month = true;
 164       } else if (!found_year && token.length() <= 5) {
 165         exploded.year = atoi(token.c_str());
 166         found_year = true;
 167       } else {
 168         // If we're here, it means we've either found an extra numeric field,
 169         // or a numeric field which was too long.  For well-formed input, the
 170         // following check would be reasonable:
 171         // NOTREACHED();
 172       }
 173     }
 174   }
 175
 176   if (!found_day_of_month || !found_month || !found_time || !found_year) {
 177     // We didn't find all of the fields we need.  For well-formed input, the
 178     // following check would be reasonable:
 179     // NOTREACHED() << "Cookie parse expiration failed: " << time_string;
 180     return base::Time();
 181   }
 182
 183   // Normalize the year to expand abbreviated years to the full year.
 184   if (exploded.year >= 69 && exploded.year <= 99)
 185     exploded.year += 1900;
 186   if (exploded.year >= 0 && exploded.year <= 68)
 187     exploded.year += 2000;
 188
 189   // If our values are within their correct ranges, we got our time.
 190   if (exploded.day_of_month >= 1 && exploded.day_of_month <= 31 &&
 191       exploded.month >= 1 && exploded.month <= 12 &&
 192       exploded.year >= 1601 && exploded.year <= 30827 &&
 193       exploded.hour <= 23 && exploded.minute <= 59 && exploded.second <= 59) {
 194     return base::Time::FromUTCExploded(exploded);
 195   }
 196
 197   // One of our values was out of expected range.  For well-formed input,
 198   // the following check would be reasonable:
 199   // NOTREACHED() << "Cookie exploded expiration failed: " << time_string;
 200
 201   return base::Time();
 202 }
 203
 204 GURL CookieOriginToURL(const std::string& domain, bool is_https) {
 205   if (domain.empty())
 206     return GURL();
 207
 208   const std::string scheme = is_https ? "https" : "http";
 209   const std::string host = domain[0] == '.' ? domain.substr(1) : domain;
 210   return GURL(scheme + "://" + host);
 211 }
 212
 213 void ParseRequestCookieLine(const std::string& header_value,
 214                             ParsedRequestCookies* parsed_cookies) {
 215   std::string::const_iterator i = header_value.begin();
 216   while (i != header_value.end()) {
 217     // Here we are at the beginning of a cookie.
 218
 219     // Eat whitespace.
 220     while (i != header_value.end() && *i == ' ') ++i;
 221     if (i == header_value.end()) return;
 222
 223     // Find cookie name.
 224     std::string::const_iterator cookie_name_beginning = i;
 225     while (i != header_value.end() && *i != '=') ++i;
 226     base::StringPiece cookie_name(cookie_name_beginning, i);
 227
 228     // Find cookie value.
 229     base::StringPiece cookie_value;
 230     // Cookies may have no value, in this case '=' may or may not be there.
 231     if (i != header_value.end() && i + 1 != header_value.end()) {
 232       ++i;  // Skip '='.
 233       std::string::const_iterator cookie_value_beginning = i;
 234       if (*i == '"') {
 235         ++i;  // Skip '"'.
 236         while (i != header_value.end() && *i != '"') ++i;
 237         if (i == header_value.end()) return;
 238         ++i;  // Skip '"'.
 239         cookie_value = base::StringPiece(cookie_value_beginning, i);
 240         // i points to character after '"', potentially a ';'.
 241       } else {
 242         while (i != header_value.end() && *i != ';') ++i;
 243         cookie_value = base::StringPiece(cookie_value_beginning, i);
 244         // i points to ';' or end of string.
 245       }
 246     }
 247     parsed_cookies->push_back(std::make_pair(cookie_name, cookie_value));
 248     // Eat ';'.
 249     if (i != header_value.end()) ++i;
 250   }
 251 }
 252
 253 std::string SerializeRequestCookieLine(
 254     const ParsedRequestCookies& parsed_cookies) {
 255   std::string buffer;
 256   for (ParsedRequestCookies::const_iterator i = parsed_cookies.begin();
 257        i != parsed_cookies.end(); ++i) {
 258     if (!buffer.empty())
 259       buffer.append("; ");
 260     buffer.append(i->first.begin(), i->first.end());
 261     buffer.push_back('=');
 262     buffer.append(i->second.begin(), i->second.end());
 263   }
 264   return buffer;
 265 }
 266
 267 }  // namespace cookie_utils
 268 }  // namespace net
 269