Rewrite PeerConnection integration tests using better testing practices.

webrtc/pc/iceserverparsing.cc

+/*
+ *  Copyright 2017 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "webrtc/pc/iceserverparsing.h"
+
+#include <cctype>  // For std::isdigit.
+#include <string>
+
+#include "webrtc/base/arraysize.h"
+
+namespace webrtc {
+
+// The min number of tokens must present in Turn host uri.
+// e.g. user@turn.example.org
+static const size_t kTurnHostTokensNum = 2;
+// Number of tokens must be preset when TURN uri has transport param.
+static const size_t kTurnTransportTokensNum = 2;
+// The default stun port.
+static const int kDefaultStunPort = 3478;
+static const int kDefaultStunTlsPort = 5349;
+static const char kTransport[] = "transport";
+
+// NOTE: Must be in the same order as the ServiceType enum.
+static const char* kValidIceServiceTypes[] = {"stun", "stuns", "turn", "turns"};
+
+// NOTE: A loop below assumes that the first value of this enum is 0 and all
+// other values are incremental.
+enum ServiceType {
+  STUN = 0,  // Indicates a STUN server.
+  STUNS,     // Indicates a STUN server used with a TLS session.
+  TURN,      // Indicates a TURN server
+  TURNS,     // Indicates a TURN server used with a TLS session.
+  INVALID,   // Unknown.
+};
+static_assert(INVALID == arraysize(kValidIceServiceTypes),
+              "kValidIceServiceTypes must have as many strings as ServiceType "
+              "has values.");
+
+// |in_str| should be of format
+// stunURI       = scheme ":" stun-host [ ":" stun-port ]
+// scheme        = "stun" / "stuns"
+// stun-host     = IP-literal / IPv4address / reg-name
+// stun-port     = *DIGIT
+//
+// draft-petithuguenin-behave-turn-uris-01
+// turnURI       = scheme ":" turn-host [ ":" turn-port ]
+// turn-host     = username@IP-literal / IPv4address / reg-name
+static bool GetServiceTypeAndHostnameFromUri(const std::string& in_str,
+                                             ServiceType* service_type,
+                                             std::string* hostname) {
+  const std::string::size_type colonpos = in_str.find(':');
+  if (colonpos == std::string::npos) {
+    LOG(LS_WARNING) << "Missing ':' in ICE URI: " << in_str;
+    return false;
+  }
+  if ((colonpos + 1) == in_str.length()) {
+    LOG(LS_WARNING) << "Empty hostname in ICE URI: " << in_str;
+    return false;
+  }
+  *service_type = INVALID;
+  for (size_t i = 0; i < arraysize(kValidIceServiceTypes); ++i) {
+    if (in_str.compare(0, colonpos, kValidIceServiceTypes[i]) == 0) {
+      *service_type = static_cast<ServiceType>(i);
+      break;
+    }
+  }
+  if (*service_type == INVALID) {
+    return false;
+  }
+  *hostname = in_str.substr(colonpos + 1, std::string::npos);
+  return true;
+}
+
+static bool ParsePort(const std::string& in_str, int* port) {
+  // Make sure port only contains digits. FromString doesn't check this.
+  for (const char& c : in_str) {
+    if (!std::isdigit(c)) {
+      return false;
+    }
+  }
+  return rtc::FromString(in_str, port);
+}
+
+// This method parses IPv6 and IPv4 literal strings, along with hostnames in
+// standard hostname:port format.
+// Consider following formats as correct.
+// |hostname:port|, |[IPV6 address]:port|, |IPv4 address|:port,
+// |hostname|, |[IPv6 address]|, |IPv4 address|.
+static bool ParseHostnameAndPortFromString(const std::string& in_str,
+                                           std::string* host,
+                                           int* port) {
+  RTC_DCHECK(host->empty());
+  if (in_str.at(0) == '[') {
+    std::string::size_type closebracket = in_str.rfind(']');
+    if (closebracket != std::string::npos) {
+      std::string::size_type colonpos = in_str.find(':', closebracket);
+      if (std::string::npos != colonpos) {
+        if (!ParsePort(in_str.substr(closebracket + 2, std::string::npos),
+                       port)) {
+          return false;
+        }
+      }
+      *host = in_str.substr(1, closebracket - 1);
+    } else {
+      return false;
+    }
+  } else {
+    std::string::size_type colonpos = in_str.find(':');
+    if (std::string::npos != colonpos) {
+      if (!ParsePort(in_str.substr(colonpos + 1, std::string::npos), port)) {
+        return false;
+      }
+      *host = in_str.substr(0, colonpos);
+    } else {
+      *host = in_str;
+    }
+  }
+  return !host->empty();
+}
+
+// Adds a STUN or TURN server to the appropriate list,
+// by parsing |url| and using the username/password in |server|.
+static RTCErrorType ParseIceServerUrl(
+    const PeerConnectionInterface::IceServer& server,
+    const std::string& url,
+    cricket::ServerAddresses* stun_servers,
+    std::vector<cricket::RelayServerConfig>* turn_servers) {
+  // draft-nandakumar-rtcweb-stun-uri-01
+  // stunURI       = scheme ":" stun-host [ ":" stun-port ]
+  // scheme        = "stun" / "stuns"
+  // stun-host     = IP-literal / IPv4address / reg-name
+  // stun-port     = *DIGIT
+
+  // draft-petithuguenin-behave-turn-uris-01
+  // turnURI       = scheme ":" turn-host [ ":" turn-port ]
+  //                 [ "?transport=" transport ]
+  // scheme        = "turn" / "turns"
+  // transport     = "udp" / "tcp" / transport-ext
+  // transport-ext = 1*unreserved
+  // turn-host     = IP-literal / IPv4address / reg-name
+  // turn-port     = *DIGIT
+  RTC_DCHECK(stun_servers != nullptr);
+  RTC_DCHECK(turn_servers != nullptr);
+  std::vector<std::string> tokens;
+  cricket::ProtocolType turn_transport_type = cricket::PROTO_UDP;
+  RTC_DCHECK(!url.empty());
+  rtc::tokenize_with_empty_tokens(url, '?', &tokens);
+  std::string uri_without_transport = tokens[0];
+  // Let's look into transport= param, if it exists.
+  if (tokens.size() == kTurnTransportTokensNum) {  // ?transport= is present.
+    std::string uri_transport_param = tokens[1];
+    rtc::tokenize_with_empty_tokens(uri_transport_param, '=', &tokens);
+    if (tokens[0] != kTransport) {
+      LOG(LS_WARNING) << "Invalid transport parameter key.";
+      return RTCErrorType::SYNTAX_ERROR;
+    }
+    if (tokens.size() < 2) {
+      LOG(LS_WARNING) << "Transport parameter missing value.";
+      return RTCErrorType::SYNTAX_ERROR;
+    }
+    if (!cricket::StringToProto(tokens[1].c_str(), &turn_transport_type) ||
+        (turn_transport_type != cricket::PROTO_UDP &&
+         turn_transport_type != cricket::PROTO_TCP)) {
+      LOG(LS_WARNING) << "Transport parameter should always be udp or tcp.";
+      return RTCErrorType::SYNTAX_ERROR;
+    }
+  }
+
+  std::string hoststring;
+  ServiceType service_type;
+  if (!GetServiceTypeAndHostnameFromUri(uri_without_transport, &service_type,
+                                        &hoststring)) {
+    LOG(LS_WARNING) << "Invalid transport parameter in ICE URI: " << url;
+    return RTCErrorType::SYNTAX_ERROR;
+  }
+
+  // GetServiceTypeAndHostnameFromUri should never give an empty hoststring
+  RTC_DCHECK(!hoststring.empty());
+
+  // Let's break hostname.
+  tokens.clear();
+  rtc::tokenize_with_empty_tokens(hoststring, '@', &tokens);
+
+  std::string username(server.username);
+  if (tokens.size() > kTurnHostTokensNum) {
+    LOG(LS_WARNING) << "Invalid user@hostname format: " << hoststring;
+    return RTCErrorType::SYNTAX_ERROR;
+  }
+  if (tokens.size() == kTurnHostTokensNum) {
+    if (tokens[0].empty() || tokens[1].empty()) {
+      LOG(LS_WARNING) << "Invalid user@hostname format: " << hoststring;
+      return RTCErrorType::SYNTAX_ERROR;
+    }
+    username.assign(rtc::s_url_decode(tokens[0]));
+    hoststring = tokens[1];
+  } else {
+    hoststring = tokens[0];
+  }
+
+  int port = kDefaultStunPort;
+  if (service_type == TURNS) {
+    port = kDefaultStunTlsPort;
+    turn_transport_type = cricket::PROTO_TLS;
+  }
+
+  std::string address;
+  if (!ParseHostnameAndPortFromString(hoststring, &address, &port)) {
+    LOG(WARNING) << "Invalid hostname format: " << uri_without_transport;
+    return RTCErrorType::SYNTAX_ERROR;
+  }
+
+  if (port <= 0 || port > 0xffff) {
+    LOG(WARNING) << "Invalid port: " << port;
+    return RTCErrorType::SYNTAX_ERROR;
+  }
+
+  switch (service_type) {
+    case STUN:
+    case STUNS:
+      stun_servers->insert(rtc::SocketAddress(address, port));
+      break;
+    case TURN:
+    case TURNS: {
+      if (username.empty() || server.password.empty()) {
+        // The WebRTC spec requires throwing an InvalidAccessError when username
+        // or credential are ommitted; this is the native equivalent.
+        return RTCErrorType::INVALID_PARAMETER;
+      }
+      cricket::RelayServerConfig config = cricket::RelayServerConfig(
+          address, port, username, server.password, turn_transport_type);
+      if (server.tls_cert_policy ==
+          PeerConnectionInterface::kTlsCertPolicyInsecureNoCheck) {
+        config.tls_cert_policy =
+            cricket::TlsCertPolicy::TLS_CERT_POLICY_INSECURE_NO_CHECK;
+      }
+      turn_servers->push_back(config);
+      break;
+    }
+    default:
+      // We shouldn't get to this point with an invalid service_type, we should
+      // have returned an error already.
+      RTC_NOTREACHED() << "Unexpected service type";
+      return RTCErrorType::INTERNAL_ERROR;
+  }
+  return RTCErrorType::NONE;
+}
+
+RTCErrorType ParseIceServers(
+    const PeerConnectionInterface::IceServers& servers,
+    cricket::ServerAddresses* stun_servers,
+    std::vector<cricket::RelayServerConfig>* turn_servers) {
+  for (const PeerConnectionInterface::IceServer& server : servers) {
+    if (!server.urls.empty()) {
+      for (const std::string& url : server.urls) {
+        if (url.empty()) {
+          LOG(LS_ERROR) << "Empty uri.";
+          return RTCErrorType::SYNTAX_ERROR;
+        }
+        RTCErrorType err =
+            ParseIceServerUrl(server, url, stun_servers, turn_servers);
+        if (err != RTCErrorType::NONE) {
+          return err;
+        }
+      }
+    } else if (!server.uri.empty()) {
+      // Fallback to old .uri if new .urls isn't present.
+      RTCErrorType err =
+          ParseIceServerUrl(server, server.uri, stun_servers, turn_servers);
+      if (err != RTCErrorType::NONE) {
+        return err;
+      }
+    } else {
+      LOG(LS_ERROR) << "Empty uri.";
+      return RTCErrorType::SYNTAX_ERROR;
+    }
+  }
+  // Candidates must have unique priorities, so that connectivity checks
+  // are performed in a well-defined order.
+  int priority = static_cast<int>(turn_servers->size() - 1);
+  for (cricket::RelayServerConfig& turn_server : *turn_servers) {
+    // First in the list gets highest priority.
+    turn_server.priority = priority--;
+  }
+  return RTCErrorType::NONE;
+}
+
+}  // namespace webrtc