Reland: Move PVer4 related code from util.* to v4_protocol_manager_util.*

components/safe_browsing_db/util.cc

 // Copyright (c) 2015 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 "components/safe_browsing_db/util.h"
 
 #include <stddef.h>
 
 #include "base/macros.h"
-#include "base/strings/string_util.h"
 #include "base/trace_event/trace_event.h"
+#include "components/safe_browsing_db/v4_protocol_manager_util.h"
 #include "crypto/sha2.h"
 #include "net/base/escape.h"
 #include "url/gurl.h"
-#include "url/url_util.h"
 
 namespace safe_browsing {
 
 // Utility functions -----------------------------------------------------------
 
 namespace {
 
 bool IsKnownList(const std::string& name) {
   for (size_t i = 0; i < arraysize(kAllLists); ++i) {
     if (!strcmp(kAllLists[i], name.c_str())) {
       return true;
     }
   }
   return false;
 }
 
-void GenerateHostVariantsToCheck(const std::string& host,
-                                 std::vector<std::string>* hosts) {
-  hosts->clear();
-
-  if (host.empty())
-    return;
-
-  // Per the Safe Browsing Protocol v2 spec, we try the host, and also up to 4
-  // hostnames formed by starting with the last 5 components and successively
-  // removing the leading component.  The last component isn't examined alone,
-  // since it's the TLD or a subcomponent thereof.
-  //
-  // Note that we don't need to be clever about stopping at the "real" eTLD --
-  // the data on the server side has been filtered to ensure it will not
-  // blacklist a whole TLD, and it's not significantly slower on our side to
-  // just check too much.
-  //
-  // Also note that because we have a simple blacklist, not some sort of complex
-  // whitelist-in-blacklist or vice versa, it doesn't matter what order we check
-  // these in.
-  const size_t kMaxHostsToCheck = 4;
-  bool skipped_last_component = false;
-  for (std::string::const_reverse_iterator i(host.rbegin());
-       i != host.rend() && hosts->size() < kMaxHostsToCheck; ++i) {
-    if (*i == '.') {
-      if (skipped_last_component)
-        hosts->push_back(std::string(i.base(), host.end()));
-      else
-        skipped_last_component = true;
-    }
-  }
-  hosts->push_back(host);
-}
-
-void GeneratePathVariantsToCheck(const std::string& path,
-                                 const std::string& query,
-                                 std::vector<std::string>* paths) {
-  paths->clear();
-
-  if (path.empty())
-    return;
-
-  // Per the Safe Browsing Protocol v2 spec, we try the exact path with/without
-  // the query parameters, and also up to 4 paths formed by starting at the root
-  // and adding more path components.
-  //
-  // As with the hosts above, it doesn't matter what order we check these in.
-  const size_t kMaxPathsToCheck = 4;
-  for (std::string::const_iterator i(path.begin());
-       i != path.end() && paths->size() < kMaxPathsToCheck; ++i) {
-    if (*i == '/')
-      paths->push_back(std::string(path.begin(), i + 1));
-  }
-
-  if (!paths->empty() && paths->back() != path)
-    paths->push_back(path);
-
-  if (!query.empty())
-    paths->push_back(path + "?" + query);
-}
-
 }  // namespace
 
 // ThreatMetadata ------------------------------------------------------------
 ThreatMetadata::ThreatMetadata()
     : threat_pattern_type(ThreatPatternType::NONE) {}
 
 ThreatMetadata::ThreatMetadata(const ThreatMetadata& other) = default;
 
 ThreatMetadata::~ThreatMetadata() {}
 
@@ skipping 106 matching lines @@
   SBFullHash hash_out;
   memcpy(hash_out.full_hash, hash_in.data(), crypto::kSHA256Length);
   return hash_out;
 }
 
 std::string SBFullHashToString(const SBFullHash& hash) {
   DCHECK_EQ(crypto::kSHA256Length, sizeof(hash.full_hash));
   return std::string(hash.full_hash, sizeof(hash.full_hash));
 }
 
-
-std::string Unescape(const std::string& url) {
-  std::string unescaped_str(url);
-  const int kMaxLoopIterations = 1024;
-  size_t old_size = 0;
-  int loop_var = 0;
-  do {
-    old_size = unescaped_str.size();
-    unescaped_str = net::UnescapeURLComponent(
-        unescaped_str,
-        net::UnescapeRule::SPOOFING_AND_CONTROL_CHARS |
-            net::UnescapeRule::SPACES | net::UnescapeRule::PATH_SEPARATORS |
-            net::UnescapeRule::URL_SPECIAL_CHARS_EXCEPT_PATH_SEPARATORS);
-  } while (old_size != unescaped_str.size() &&
-           ++loop_var <= kMaxLoopIterations);
-
-  return unescaped_str;
-}
-
-std::string Escape(const std::string& url) {
-  std::string escaped_str;
-  // The escaped string is larger so allocate double the length to reduce the
-  // chance of the string being grown.
-  escaped_str.reserve(url.length() * 2);
-  const char* kHexString = "0123456789ABCDEF";
-  for (size_t i = 0; i < url.length(); i++) {
-    unsigned char c = static_cast<unsigned char>(url[i]);
-    if (c <= ' ' || c > '~' || c == '#' || c == '%') {
-      escaped_str += '%';
-      escaped_str += kHexString[c >> 4];
-      escaped_str += kHexString[c & 0xf];
-    } else {
-      escaped_str += c;
-    }
-  }
-
-  return escaped_str;
-}
-
-std::string RemoveConsecutiveChars(base::StringPiece str, const char c) {
-  std::string output;
-  // Output is at most the length of the original string.
-  output.reserve(str.size());
-
-  size_t i = 0;
-  while (i < str.size()) {
-    output.append(1, str[i++]);
-    if (str[i - 1] == c) {
-      while (i < str.size() && str[i] == c) {
-        i++;
-      }
-    }
-  }
-
-  return output;
-}
-
-// Canonicalizes url as per Google Safe Browsing Specification.
-// See section 6.1 in
-// http://code.google.com/p/google-safe-browsing/wiki/Protocolv2Spec.
-void CanonicalizeUrl(const GURL& url,
-                     std::string* canonicalized_hostname,
-                     std::string* canonicalized_path,
-                     std::string* canonicalized_query) {
-  DCHECK(url.is_valid());
-
-  // We only canonicalize "normal" URLs.
-  if (!url.IsStandard())
-    return;
-
-  // Following canonicalization steps are excluded since url parsing takes care
-  // of those :-
-  // 1. Remove any tab (0x09), CR (0x0d), and LF (0x0a) chars from url.
-  //    (Exclude escaped version of these chars).
-  // 2. Normalize hostname to 4 dot-seperated decimal values.
-  // 3. Lowercase hostname.
-  // 4. Resolve path sequences "/../" and "/./".
-
-  // That leaves us with the following :-
-  // 1. Remove fragment in URL.
-  GURL url_without_fragment;
-  GURL::Replacements f_replacements;
-  f_replacements.ClearRef();
-  f_replacements.ClearUsername();
-  f_replacements.ClearPassword();
-  url_without_fragment = url.ReplaceComponents(f_replacements);
-
-  // 2. Do URL unescaping until no more hex encoded characters exist.
-  std::string url_unescaped_str(Unescape(url_without_fragment.spec()));
-  url::Parsed parsed;
-  url::ParseStandardURL(url_unescaped_str.data(), url_unescaped_str.length(),
-                        &parsed);
-
-  // 3. In hostname, remove all leading and trailing dots.
-  base::StringPiece host;
-  if (parsed.host.len > 0)
-    host.set(url_unescaped_str.data() + parsed.host.begin, parsed.host.len);
-
-  base::StringPiece host_without_end_dots =
-      base::TrimString(host, ".", base::TrimPositions::TRIM_ALL);
-
-  // 4. In hostname, replace consecutive dots with a single dot.
-  std::string host_without_consecutive_dots(RemoveConsecutiveChars(
-      host_without_end_dots, '.'));
-
-  // 5. In path, replace runs of consecutive slashes with a single slash.
-  base::StringPiece path;
-  if (parsed.path.len > 0)
-    path.set(url_unescaped_str.data() + parsed.path.begin, parsed.path.len);
-  std::string path_without_consecutive_slash(RemoveConsecutiveChars(path, '/'));
-
-  url::Replacements<char> hp_replacements;
-  hp_replacements.SetHost(
-      host_without_consecutive_dots.data(),
-      url::Component(0, host_without_consecutive_dots.length()));
-  hp_replacements.SetPath(
-      path_without_consecutive_slash.data(),
-      url::Component(0, path_without_consecutive_slash.length()));
-
-  std::string url_unescaped_with_can_hostpath;
-  url::StdStringCanonOutput output(&url_unescaped_with_can_hostpath);
-  url::Parsed temp_parsed;
-  url::ReplaceComponents(url_unescaped_str.data(),
-                         url_unescaped_str.length(),
-                         parsed,
-                         hp_replacements,
-                         NULL,
-                         &output,
-                         &temp_parsed);
-  output.Complete();
-
-  // 6. Step needed to revert escaping done in url::ReplaceComponents.
-  url_unescaped_with_can_hostpath = Unescape(url_unescaped_with_can_hostpath);
-
-  // 7. After performing all above steps, percent-escape all chars in url which
-  // are <= ASCII 32, >= 127, #, %. Escapes must be uppercase hex characters.
-  std::string escaped_canon_url_str(Escape(url_unescaped_with_can_hostpath));
-  url::Parsed final_parsed;
-  url::ParseStandardURL(escaped_canon_url_str.data(),
-                        escaped_canon_url_str.length(),
-                        &final_parsed);
-
-  if (canonicalized_hostname && final_parsed.host.len > 0) {
-    *canonicalized_hostname =
-        escaped_canon_url_str.substr(final_parsed.host.begin,
-                                     final_parsed.host.len);
-  }
-  if (canonicalized_path && final_parsed.path.len > 0) {
-    *canonicalized_path = escaped_canon_url_str.substr(final_parsed.path.begin,
-                                                       final_parsed.path.len);
-  }
-  if (canonicalized_query && final_parsed.query.len > 0) {
-    *canonicalized_query = escaped_canon_url_str.substr(
-        final_parsed.query.begin, final_parsed.query.len);
-  }
-}
-
 void UrlToFullHashes(const GURL& url,
                      bool include_whitelist_hashes,
                      std::vector<SBFullHash>* full_hashes) {
   // Include this function in traces because it's not cheap so it should be
   // called sparingly.
   TRACE_EVENT2("loader", "safe_browsing::UrlToFullHashes", "url", url.spec(),
                "include_whitelist_hashes", include_whitelist_hashes);
   std::string canon_host;
   std::string canon_path;
   std::string canon_query;
-  CanonicalizeUrl(url, &canon_host, &canon_path, &canon_query);
+  V4ProtocolManagerUtil::CanonicalizeUrl(url, &canon_host, &canon_path,
+                                         &canon_query);
 
   std::vector<std::string> hosts;
   if (url.HostIsIPAddress()) {
     hosts.push_back(url.host());
   } else {
-    GenerateHostVariantsToCheck(canon_host, &hosts);
+    V4ProtocolManagerUtil::GenerateHostVariantsToCheck(canon_host, &hosts);
   }
 
   std::vector<std::string> paths;
-  GeneratePathVariantsToCheck(canon_path, canon_query, &paths);
+  V4ProtocolManagerUtil::GeneratePathVariantsToCheck(canon_path, canon_query,
+                                                     &paths);
 
   for (const std::string& host : hosts) {
     for (const std::string& path : paths) {
       full_hashes->push_back(
           SBFullHashForString(host + path));
 
       // We may have /foo as path-prefix in the whitelist which should
       // also match with /foo/bar and /foo?bar.  Hence, for every path
       // that ends in '/' we also add the path without the slash.
       if (include_whitelist_hashes && path.size() > 1 && path.back() == '/') {
         full_hashes->push_back(SBFullHashForString(
             host + path.substr(0, path.size() - 1)));
       }
     }
   }
 }
 
-void GenerateHostsToCheck(const GURL& url, std::vector<std::string>* hosts) {
-  std::string canon_host;
-  CanonicalizeUrl(url, &canon_host, NULL, NULL);
-  GenerateHostVariantsToCheck(canon_host, hosts);
-}
-
-void GeneratePathsToCheck(const GURL& url, std::vector<std::string>* paths) {
-  std::string canon_path;
-  std::string canon_query;
-  CanonicalizeUrl(url, NULL, &canon_path, &canon_query);
-  GeneratePathVariantsToCheck(canon_path, canon_query, paths);
-}
-
-void GeneratePatternsToCheck(const GURL& url, std::vector<std::string>* urls) {
-  std::string canon_host;
-  std::string canon_path;
-  std::string canon_query;
-  CanonicalizeUrl(url, &canon_host, &canon_path, &canon_query);
-
-  std::vector<std::string> hosts, paths;
-  GenerateHostVariantsToCheck(canon_host, &hosts);
-  GeneratePathVariantsToCheck(canon_path, canon_query, &paths);
-  for (size_t h = 0; h < hosts.size(); ++h) {
-    for (size_t p = 0; p < paths.size(); ++p) {
-      urls->push_back(hosts[h] + paths[p]);
-    }
-  }
-}
-
 }  // namespace safe_browsing