net/proxy/proxy_bypass_rules.cc

   1 // Copyright (c) 2011 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/proxy/proxy_bypass_rules.h"
   6
   7 #include "base/stl_util.h"
   8 #include "base/strings/string_number_conversions.h"
   9 #include "base/strings/string_piece.h"
  10 #include "base/strings/string_tokenizer.h"
  11 #include "base/strings/string_util.h"
  12 #include "base/strings/stringprintf.h"
  13 #include "net/base/host_port_pair.h"
  14 #include "net/base/ip_address_number.h"
  15 #include "net/base/net_util.h"
  16
  17 namespace net {
  18
  19 namespace {
  20
  21 class HostnamePatternRule : public ProxyBypassRules::Rule {
  22  public:
  23   HostnamePatternRule(const std::string& optional_scheme,
  24                       const std::string& hostname_pattern,
  25                       int optional_port)
  26       : optional_scheme_(base::StringToLowerASCII(optional_scheme)),
  27         hostname_pattern_(base::StringToLowerASCII(hostname_pattern)),
  28         optional_port_(optional_port) {
  29   }
  30
  31   bool Matches(const GURL& url) const override {
  32     if (optional_port_ != -1 && url.EffectiveIntPort() != optional_port_)
  33       return false;  // Didn't match port expectation.
  34
  35     if (!optional_scheme_.empty() && url.scheme() != optional_scheme_)
  36       return false;  // Didn't match scheme expectation.
  37
  38     // Note it is necessary to lower-case the host, since GURL uses capital
  39     // letters for percent-escaped characters.
  40     return MatchPattern(base::StringToLowerASCII(url.host()),
  41                         hostname_pattern_);
  42   }
  43
  44   std::string ToString() const override {
  45     std::string str;
  46     if (!optional_scheme_.empty())
  47       base::StringAppendF(&str, "%s://", optional_scheme_.c_str());
  48     str += hostname_pattern_;
  49     if (optional_port_ != -1)
  50       base::StringAppendF(&str, ":%d", optional_port_);
  51     return str;
  52   }
  53
  54   Rule* Clone() const override {
  55     return new HostnamePatternRule(optional_scheme_,
  56                                    hostname_pattern_,
  57                                    optional_port_);
  58   }
  59
  60  private:
  61   const std::string optional_scheme_;
  62   const std::string hostname_pattern_;
  63   const int optional_port_;
  64 };
  65
  66 class BypassLocalRule : public ProxyBypassRules::Rule {
  67  public:
  68   bool Matches(const GURL& url) const override {
  69     const std::string& host = url.host();
  70     if (host == "127.0.0.1" || host == "[::1]")
  71       return true;
  72     return host.find('.') == std::string::npos;
  73   }
  74
  75   std::string ToString() const override { return "<local>"; }
  76
  77   Rule* Clone() const override { return new BypassLocalRule(); }
  78 };
  79
  80 // Rule for matching a URL that is an IP address, if that IP address falls
  81 // within a certain numeric range. For example, you could use this rule to
  82 // match all the IPs in the CIDR block 10.10.3.4/24.
  83 class BypassIPBlockRule : public ProxyBypassRules::Rule {
  84  public:
  85   // |ip_prefix| + |prefix_length| define the IP block to match.
  86   BypassIPBlockRule(const std::string& description,
  87                     const std::string& optional_scheme,
  88                     const IPAddressNumber& ip_prefix,
  89                     size_t prefix_length_in_bits)
  90       : description_(description),
  91         optional_scheme_(optional_scheme),
  92         ip_prefix_(ip_prefix),
  93         prefix_length_in_bits_(prefix_length_in_bits) {
  94   }
  95
  96   bool Matches(const GURL& url) const override {
  97     if (!url.HostIsIPAddress())
  98       return false;
  99
 100     if (!optional_scheme_.empty() && url.scheme() != optional_scheme_)
 101       return false;  // Didn't match scheme expectation.
 102
 103     // Parse the input IP literal to a number.
 104     IPAddressNumber ip_number;
 105     if (!ParseIPLiteralToNumber(url.HostNoBrackets(), &ip_number))
 106       return false;
 107
 108     // Test if it has the expected prefix.
 109     return IPNumberMatchesPrefix(ip_number, ip_prefix_,
 110                                  prefix_length_in_bits_);
 111   }
 112
 113   std::string ToString() const override { return description_; }
 114
 115   Rule* Clone() const override {
 116     return new BypassIPBlockRule(description_,
 117                                  optional_scheme_,
 118                                  ip_prefix_,
 119                                  prefix_length_in_bits_);
 120   }
 121
 122  private:
 123   const std::string description_;
 124   const std::string optional_scheme_;
 125   const IPAddressNumber ip_prefix_;
 126   const size_t prefix_length_in_bits_;
 127 };
 128
 129 // Returns true if the given string represents an IP address.
 130 // IPv6 addresses are expected to be bracketed.
 131 bool IsIPAddress(const std::string& domain) {
 132   // From GURL::HostIsIPAddress()
 133   url::RawCanonOutputT<char, 128> ignored_output;
 134   url::CanonHostInfo host_info;
 135   url::Component domain_comp(0, domain.size());
 136   url::CanonicalizeIPAddress(domain.c_str(), domain_comp, &ignored_output,
 137                              &host_info);
 138   return host_info.IsIPAddress();
 139 }
 140
 141 }  // namespace
 142
 143 ProxyBypassRules::Rule::Rule() {
 144 }
 145
 146 ProxyBypassRules::Rule::~Rule() {
 147 }
 148
 149 bool ProxyBypassRules::Rule::Equals(const Rule& rule) const {
 150   return ToString() == rule.ToString();
 151 }
 152
 153 ProxyBypassRules::ProxyBypassRules() {
 154 }
 155
 156 ProxyBypassRules::ProxyBypassRules(const ProxyBypassRules& rhs) {
 157   AssignFrom(rhs);
 158 }
 159
 160 ProxyBypassRules::~ProxyBypassRules() {
 161   Clear();
 162 }
 163
 164 ProxyBypassRules& ProxyBypassRules::operator=(const ProxyBypassRules& rhs) {
 165   AssignFrom(rhs);
 166   return *this;
 167 }
 168
 169 bool ProxyBypassRules::Matches(const GURL& url) const {
 170   for (RuleList::const_iterator it = rules_.begin(); it != rules_.end(); ++it) {
 171     if ((*it)->Matches(url))
 172       return true;
 173   }
 174   return false;
 175 }
 176
 177 bool ProxyBypassRules::Equals(const ProxyBypassRules& other) const {
 178   if (rules_.size() != other.rules_.size())
 179     return false;
 180
 181   for (size_t i = 0; i < rules_.size(); ++i) {
 182     if (!rules_[i]->Equals(*other.rules_[i]))
 183       return false;
 184   }
 185   return true;
 186 }
 187
 188 void ProxyBypassRules::ParseFromString(const std::string& raw) {
 189   ParseFromStringInternal(raw, false);
 190 }
 191
 192 void ProxyBypassRules::ParseFromStringUsingSuffixMatching(
 193     const std::string& raw) {
 194   ParseFromStringInternal(raw, true);
 195 }
 196
 197 bool ProxyBypassRules::AddRuleForHostname(const std::string& optional_scheme,
 198                                           const std::string& hostname_pattern,
 199                                           int optional_port) {
 200   if (hostname_pattern.empty())
 201     return false;
 202
 203   rules_.push_back(new HostnamePatternRule(optional_scheme,
 204                                            hostname_pattern,
 205                                            optional_port));
 206   return true;
 207 }
 208
 209 void ProxyBypassRules::AddRuleToBypassLocal() {
 210   rules_.push_back(new BypassLocalRule);
 211 }
 212
 213 bool ProxyBypassRules::AddRuleFromString(const std::string& raw) {
 214   return AddRuleFromStringInternalWithLogging(raw, false);
 215 }
 216
 217 bool ProxyBypassRules::AddRuleFromStringUsingSuffixMatching(
 218     const std::string& raw) {
 219   return AddRuleFromStringInternalWithLogging(raw, true);
 220 }
 221
 222 std::string ProxyBypassRules::ToString() const {
 223   std::string result;
 224   for (RuleList::const_iterator rule(rules_.begin());
 225        rule != rules_.end();
 226        ++rule) {
 227     result += (*rule)->ToString();
 228     result += ";";
 229   }
 230   return result;
 231 }
 232
 233 void ProxyBypassRules::Clear() {
 234   STLDeleteElements(&rules_);
 235 }
 236
 237 void ProxyBypassRules::AssignFrom(const ProxyBypassRules& other) {
 238   Clear();
 239
 240   // Make a copy of the rules list.
 241   for (RuleList::const_iterator it = other.rules_.begin();
 242        it != other.rules_.end(); ++it) {
 243     rules_.push_back((*it)->Clone());
 244   }
 245 }
 246
 247 void ProxyBypassRules::ParseFromStringInternal(
 248     const std::string& raw,
 249     bool use_hostname_suffix_matching) {
 250   Clear();
 251
 252   base::StringTokenizer entries(raw, ",;");
 253   while (entries.GetNext()) {
 254     AddRuleFromStringInternalWithLogging(entries.token(),
 255                                          use_hostname_suffix_matching);
 256   }
 257 }
 258
 259 bool ProxyBypassRules::AddRuleFromStringInternal(
 260     const std::string& raw_untrimmed,
 261     bool use_hostname_suffix_matching) {
 262   std::string raw;
 263   base::TrimWhitespaceASCII(raw_untrimmed, base::TRIM_ALL, &raw);
 264
 265   // This is the special syntax used by WinInet's bypass list -- we allow it
 266   // on all platforms and interpret it the same way.
 267   if (base::LowerCaseEqualsASCII(raw, "<local>")) {
 268     AddRuleToBypassLocal();
 269     return true;
 270   }
 271
 272   // Extract any scheme-restriction.
 273   std::string::size_type scheme_pos = raw.find("://");
 274   std::string scheme;
 275   if (scheme_pos != std::string::npos) {
 276     scheme = raw.substr(0, scheme_pos);
 277     raw = raw.substr(scheme_pos + 3);
 278     if (scheme.empty())
 279       return false;
 280   }
 281
 282   if (raw.empty())
 283     return false;
 284
 285   // If there is a forward slash in the input, it is probably a CIDR style
 286   // mask.
 287   if (raw.find('/') != std::string::npos) {
 288     IPAddressNumber ip_prefix;
 289     size_t prefix_length_in_bits;
 290
 291     if (!ParseCIDRBlock(raw, &ip_prefix, &prefix_length_in_bits))
 292       return false;
 293
 294     rules_.push_back(
 295         new BypassIPBlockRule(raw, scheme, ip_prefix, prefix_length_in_bits));
 296
 297     return true;
 298   }
 299
 300   // Check if we have an <ip-address>[:port] input. We need to treat this
 301   // separately since the IP literal may not be in a canonical form.
 302   std::string host;
 303   int port;
 304   if (ParseHostAndPort(raw, &host, &port)) {
 305     // Note that HostPortPair is used to merely to convert any IPv6 literals to
 306     // a URL-safe format that can be used by canonicalization below.
 307     std::string bracketed_host = HostPortPair(host, 80).HostForURL();
 308     if (IsIPAddress(bracketed_host)) {
 309       // Canonicalize the IP literal before adding it as a string pattern.
 310       GURL tmp_url("http://" + bracketed_host);
 311       return AddRuleForHostname(scheme, tmp_url.host(), port);
 312     }
 313   }
 314
 315   // Otherwise assume we have <hostname-pattern>[:port].
 316   std::string::size_type pos_colon = raw.rfind(':');
 317   host = raw;
 318   port = -1;
 319   if (pos_colon != std::string::npos) {
 320     if (!base::StringToInt(base::StringPiece(raw.begin() + pos_colon + 1,
 321                                              raw.end()),
 322                            &port) ||
 323         (port < 0 || port > 0xFFFF)) {
 324       return false;  // Port was invalid.
 325     }
 326     raw = raw.substr(0, pos_colon);
 327   }
 328
 329   // Special-case hostnames that begin with a period.
 330   // For example, we remap ".google.com" --> "*.google.com".
 331   if (StartsWithASCII(raw, ".", false))
 332     raw = "*" + raw;
 333
 334   // If suffix matching was asked for, make sure the pattern starts with a
 335   // wildcard.
 336   if (use_hostname_suffix_matching && !StartsWithASCII(raw, "*", false))
 337     raw = "*" + raw;
 338
 339   return AddRuleForHostname(scheme, raw, port);
 340 }
 341
 342 bool ProxyBypassRules::AddRuleFromStringInternalWithLogging(
 343     const std::string& raw,
 344     bool use_hostname_suffix_matching) {
 345   return AddRuleFromStringInternal(raw, use_hostname_suffix_matching);
 346 }
 347
 348 }  // namespace net