root/net/proxy/proxy_bypass_rules.cc

DEFINITIONS

1. optional_port_
2. Matches
3. ToString
4. Clone
5. Matches
6. ToString
7. Clone
8. prefix_length_in_bits_
9. Matches
10. ToString
11. Clone
12. IsIPAddress
13. Equals
14. Matches
15. Equals
16. ParseFromString
17. ParseFromStringUsingSuffixMatching
18. AddRuleForHostname
19. AddRuleToBypassLocal
20. AddRuleFromString
21. AddRuleFromStringUsingSuffixMatching
22. ToString
23. Clear
24. AssignFrom
25. ParseFromStringInternal
26. AddRuleFromStringInternal
27. AddRuleFromStringInternalWithLogging

// Copyright (c) 2011 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.

#include "net/proxy/proxy_bypass_rules.h"

#include "base/stl_util.h"
#include "base/strings/string_number_conversions.h"
#include "base/strings/string_util.h"
#include "base/strings/stringprintf.h"
#include "base/strings/string_piece.h"
#include "base/strings/string_tokenizer.h"
#include "net/base/net_util.h"

namespace net {

namespace {

class HostnamePatternRule : public ProxyBypassRules::Rule {
 public:
  HostnamePatternRule(const std::string& optional_scheme,
                      const std::string& hostname_pattern,
                      int optional_port)
      : optional_scheme_(StringToLowerASCII(optional_scheme)),
        hostname_pattern_(StringToLowerASCII(hostname_pattern)),
        optional_port_(optional_port) {
  }

  virtual bool Matches(const GURL& url) const OVERRIDE {
    if (optional_port_ != -1 && url.EffectiveIntPort() != optional_port_)
      return false;  // Didn't match port expectation.

    if (!optional_scheme_.empty() && url.scheme() != optional_scheme_)
      return false;  // Didn't match scheme expectation.

    // Note it is necessary to lower-case the host, since GURL uses capital
    // letters for percent-escaped characters.
    return MatchPattern(StringToLowerASCII(url.host()), hostname_pattern_);
  }

  virtual std::string ToString() const OVERRIDE {
    std::string str;
    if (!optional_scheme_.empty())
      base::StringAppendF(&str, "%s://", optional_scheme_.c_str());
    str += hostname_pattern_;
    if (optional_port_ != -1)
      base::StringAppendF(&str, ":%d", optional_port_);
    return str;
  }

  virtual Rule* Clone() const OVERRIDE {
    return new HostnamePatternRule(optional_scheme_,
                                   hostname_pattern_,
                                   optional_port_);
  }

 private:
  const std::string optional_scheme_;
  const std::string hostname_pattern_;
  const int optional_port_;
};

class BypassLocalRule : public ProxyBypassRules::Rule {
 public:
  virtual bool Matches(const GURL& url) const OVERRIDE {
    const std::string& host = url.host();
    if (host == "127.0.0.1" || host == "[::1]")
      return true;
    return host.find('.') == std::string::npos;
  }

  virtual std::string ToString() const OVERRIDE {
    return "<local>";
  }

  virtual Rule* Clone() const OVERRIDE {
    return new BypassLocalRule();
  }
};

// Rule for matching a URL that is an IP address, if that IP address falls
// within a certain numeric range. For example, you could use this rule to
// match all the IPs in the CIDR block 10.10.3.4/24.
class BypassIPBlockRule : public ProxyBypassRules::Rule {
 public:
  // |ip_prefix| + |prefix_length| define the IP block to match.
  BypassIPBlockRule(const std::string& description,
                    const std::string& optional_scheme,
                    const IPAddressNumber& ip_prefix,
                    size_t prefix_length_in_bits)
      : description_(description),
        optional_scheme_(optional_scheme),
        ip_prefix_(ip_prefix),
        prefix_length_in_bits_(prefix_length_in_bits) {
  }

  virtual bool Matches(const GURL& url) const OVERRIDE {
    if (!url.HostIsIPAddress())
      return false;

    if (!optional_scheme_.empty() && url.scheme() != optional_scheme_)
      return false;  // Didn't match scheme expectation.

    // Parse the input IP literal to a number.
    IPAddressNumber ip_number;
    if (!ParseIPLiteralToNumber(url.HostNoBrackets(), &ip_number))
      return false;

    // Test if it has the expected prefix.
    return IPNumberMatchesPrefix(ip_number, ip_prefix_,
                                 prefix_length_in_bits_);
  }

  virtual std::string ToString() const OVERRIDE {
    return description_;
  }

  virtual Rule* Clone() const OVERRIDE {
    return new BypassIPBlockRule(description_,
                                 optional_scheme_,
                                 ip_prefix_,
                                 prefix_length_in_bits_);
  }

 private:
  const std::string description_;
  const std::string optional_scheme_;
  const IPAddressNumber ip_prefix_;
  const size_t prefix_length_in_bits_;
};

// Returns true if the given string represents an IP address.
bool IsIPAddress(const std::string& domain) {
  // From GURL::HostIsIPAddress()
  url_canon::RawCanonOutputT<char, 128> ignored_output;
  url_canon::CanonHostInfo host_info;
  url_parse::Component domain_comp(0, domain.size());
  url_canon::CanonicalizeIPAddress(domain.c_str(), domain_comp,
                                   &ignored_output, &host_info);
  return host_info.IsIPAddress();
}

}  // namespace

ProxyBypassRules::Rule::Rule() {
}

ProxyBypassRules::Rule::~Rule() {
}

bool ProxyBypassRules::Rule::Equals(const Rule& rule) const {
  return ToString() == rule.ToString();
}

ProxyBypassRules::ProxyBypassRules() {
}

ProxyBypassRules::ProxyBypassRules(const ProxyBypassRules& rhs) {
  AssignFrom(rhs);
}

ProxyBypassRules::~ProxyBypassRules() {
  Clear();
}

ProxyBypassRules& ProxyBypassRules::operator=(const ProxyBypassRules& rhs) {
  AssignFrom(rhs);
  return *this;
}

bool ProxyBypassRules::Matches(const GURL& url) const {
  for (RuleList::const_iterator it = rules_.begin(); it != rules_.end(); ++it) {
    if ((*it)->Matches(url))
      return true;
  }
  return false;
}

bool ProxyBypassRules::Equals(const ProxyBypassRules& other) const {
  if (rules_.size() != other.rules_.size())
    return false;

  for (size_t i = 0; i < rules_.size(); ++i) {
    if (!rules_[i]->Equals(*other.rules_[i]))
      return false;
  }
  return true;
}

void ProxyBypassRules::ParseFromString(const std::string& raw) {
  ParseFromStringInternal(raw, false);
}

void ProxyBypassRules::ParseFromStringUsingSuffixMatching(
    const std::string& raw) {
  ParseFromStringInternal(raw, true);
}

bool ProxyBypassRules::AddRuleForHostname(const std::string& optional_scheme,
                                          const std::string& hostname_pattern,
                                          int optional_port) {
  if (hostname_pattern.empty())
    return false;

  rules_.push_back(new HostnamePatternRule(optional_scheme,
                                           hostname_pattern,
                                           optional_port));
  return true;
}

void ProxyBypassRules::AddRuleToBypassLocal() {
  rules_.push_back(new BypassLocalRule);
}

bool ProxyBypassRules::AddRuleFromString(const std::string& raw) {
  return AddRuleFromStringInternalWithLogging(raw, false);
}

bool ProxyBypassRules::AddRuleFromStringUsingSuffixMatching(
    const std::string& raw) {
  return AddRuleFromStringInternalWithLogging(raw, true);
}

std::string ProxyBypassRules::ToString() const {
  std::string result;
  for (RuleList::const_iterator rule(rules_.begin());
       rule != rules_.end();
       ++rule) {
    result += (*rule)->ToString();
    result += ";";
  }
  return result;
}

void ProxyBypassRules::Clear() {
  STLDeleteElements(&rules_);
}

void ProxyBypassRules::AssignFrom(const ProxyBypassRules& other) {
  Clear();

  // Make a copy of the rules list.
  for (RuleList::const_iterator it = other.rules_.begin();
       it != other.rules_.end(); ++it) {
    rules_.push_back((*it)->Clone());
  }
}

void ProxyBypassRules::ParseFromStringInternal(
    const std::string& raw,
    bool use_hostname_suffix_matching) {
  Clear();

  base::StringTokenizer entries(raw, ",;");
  while (entries.GetNext()) {
    AddRuleFromStringInternalWithLogging(entries.token(),
                                         use_hostname_suffix_matching);
  }
}

bool ProxyBypassRules::AddRuleFromStringInternal(
    const std::string& raw_untrimmed,
    bool use_hostname_suffix_matching) {
  std::string raw;
  base::TrimWhitespaceASCII(raw_untrimmed, base::TRIM_ALL, &raw);

  // This is the special syntax used by WinInet's bypass list -- we allow it
  // on all platforms and interpret it the same way.
  if (LowerCaseEqualsASCII(raw, "<local>")) {
    AddRuleToBypassLocal();
    return true;
  }

  // Extract any scheme-restriction.
  std::string::size_type scheme_pos = raw.find("://");
  std::string scheme;
  if (scheme_pos != std::string::npos) {
    scheme = raw.substr(0, scheme_pos);
    raw = raw.substr(scheme_pos + 3);
    if (scheme.empty())
      return false;
  }

  if (raw.empty())
    return false;

  // If there is a forward slash in the input, it is probably a CIDR style
  // mask.
  if (raw.find('/') != std::string::npos) {
    IPAddressNumber ip_prefix;
    size_t prefix_length_in_bits;

    if (!ParseCIDRBlock(raw, &ip_prefix, &prefix_length_in_bits))
      return false;

    rules_.push_back(
        new BypassIPBlockRule(raw, scheme, ip_prefix, prefix_length_in_bits));

    return true;
  }

  // Check if we have an <ip-address>[:port] input. We need to treat this
  // separately since the IP literal may not be in a canonical form.
  std::string host;
  int port;
  if (ParseHostAndPort(raw, &host, &port)) {
    if (IsIPAddress(host)) {
      // Canonicalize the IP literal before adding it as a string pattern.
      GURL tmp_url("http://" + host);
      return AddRuleForHostname(scheme, tmp_url.host(), port);
    }
  }

  // Otherwise assume we have <hostname-pattern>[:port].
  std::string::size_type pos_colon = raw.rfind(':');
  host = raw;
  port = -1;
  if (pos_colon != std::string::npos) {
    if (!base::StringToInt(base::StringPiece(raw.begin() + pos_colon + 1,
                                             raw.end()),
                           &port) ||
        (port < 0 || port > 0xFFFF)) {
      return false;  // Port was invalid.
    }
    raw = raw.substr(0, pos_colon);
  }

  // Special-case hostnames that begin with a period.
  // For example, we remap ".google.com" --> "*.google.com".
  if (StartsWithASCII(raw, ".", false))
    raw = "*" + raw;

  // If suffix matching was asked for, make sure the pattern starts with a
  // wildcard.
  if (use_hostname_suffix_matching && !StartsWithASCII(raw, "*", false))
    raw = "*" + raw;

  return AddRuleForHostname(scheme, raw, port);
}

bool ProxyBypassRules::AddRuleFromStringInternalWithLogging(
    const std::string& raw,
    bool use_hostname_suffix_matching) {
  return AddRuleFromStringInternal(raw, use_hostname_suffix_matching);
}

}  // namespace net