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webrtc / src / 1131f24d2b0d399097be6a7efc7cc24e86415346 / . / api / transport / stun.cc
blob: 7ef68522607d4406ffb7c0e4c197a92c40bcafc0 [file] [log] [blame]
/*
* Copyright 2004 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 "api/transport/stun.h"
#include <string.h>
#include <algorithm>
#include <cstdint>
#include <iterator>
#include <memory>
#include <utility>
#include "rtc_base/byte_order.h"
#include "rtc_base/checks.h"
#include "rtc_base/crc32.h"
#include "rtc_base/helpers.h"
#include "rtc_base/logging.h"
#include "rtc_base/message_digest.h"
#include "system_wrappers/include/metrics.h"
using rtc::ByteBufferReader;
using rtc::ByteBufferWriter;
namespace cricket {
namespace {
const int k127Utf8CharactersLengthInBytes = 508;
const int kMessageIntegrityAttributeLength = 20;
const int kTheoreticalMaximumAttributeLength = 65535;
uint32_t ReduceTransactionId(absl::string_view transaction_id) {
RTC_DCHECK(transaction_id.length() == cricket::kStunTransactionIdLength ||
transaction_id.length() == cricket::kStunLegacyTransactionIdLength)
<< transaction_id.length();
ByteBufferReader reader(rtc::MakeArrayView(
reinterpret_cast<const uint8_t*>(transaction_id.data()),
transaction_id.size()));
uint32_t result = 0;
uint32_t next;
while (reader.ReadUInt32(&next)) {
result ^= next;
}
return result;
}
// Check the maximum length of a BYTE_STRING attribute against specifications.
bool LengthValid(int type, int length) {
// "Less than 509 bytes" is intended to indicate a maximum of 127
// UTF-8 characters, which may take up to 4 bytes per character.
switch (type) {
case STUN_ATTR_USERNAME:
return length <=
k127Utf8CharactersLengthInBytes; // RFC 8489 section 14.3
case STUN_ATTR_MESSAGE_INTEGRITY:
return length ==
kMessageIntegrityAttributeLength; // RFC 8489 section 14.5
case STUN_ATTR_REALM:
return length <=
k127Utf8CharactersLengthInBytes; // RFC 8489 section 14.9
case STUN_ATTR_NONCE:
return length <=
k127Utf8CharactersLengthInBytes; // RFC 8489 section 14.10
case STUN_ATTR_SOFTWARE:
return length <=
k127Utf8CharactersLengthInBytes; // RFC 8489 section 14.14
case STUN_ATTR_DATA:
// No length restriction in RFC; it's the content of an UDP datagram,
// which in theory can be up to 65.535 bytes.
// TODO(bugs.webrtc.org/12179): Write a test to find the real limit.
return length <= kTheoreticalMaximumAttributeLength;
default:
// Return an arbitrary restriction for all other types.
return length <= kTheoreticalMaximumAttributeLength;
}
RTC_DCHECK_NOTREACHED();
return true;
}
} // namespace
const char STUN_ERROR_REASON_TRY_ALTERNATE_SERVER[] = "Try Alternate Server";
const char STUN_ERROR_REASON_BAD_REQUEST[] = "Bad Request";
const char STUN_ERROR_REASON_UNAUTHORIZED[] = "Unauthorized";
const char STUN_ERROR_REASON_UNKNOWN_ATTRIBUTE[] = "Unknown Attribute";
const char STUN_ERROR_REASON_FORBIDDEN[] = "Forbidden";
const char STUN_ERROR_REASON_ALLOCATION_MISMATCH[] = "Allocation Mismatch";
const char STUN_ERROR_REASON_STALE_NONCE[] = "Stale Nonce";
const char STUN_ERROR_REASON_WRONG_CREDENTIALS[] = "Wrong Credentials";
const char STUN_ERROR_REASON_UNSUPPORTED_PROTOCOL[] = "Unsupported Protocol";
const char STUN_ERROR_REASON_ROLE_CONFLICT[] = "Role Conflict";
const char STUN_ERROR_REASON_SERVER_ERROR[] = "Server Error";
const char TURN_MAGIC_COOKIE_VALUE[] = {'\x72', '\xC6', '\x4B', '\xC6'};
const char EMPTY_TRANSACTION_ID[] = "0000000000000000";
const uint32_t STUN_FINGERPRINT_XOR_VALUE = 0x5354554E;
const int SERVER_NOT_REACHABLE_ERROR = 701;
// StunMessage
StunMessage::StunMessage()
: StunMessage(STUN_INVALID_MESSAGE_TYPE, EMPTY_TRANSACTION_ID) {}
StunMessage::StunMessage(uint16_t type)
: StunMessage(type, GenerateTransactionId()) {}
StunMessage::StunMessage(uint16_t type, absl::string_view transaction_id)
: type_(type),
transaction_id_(transaction_id),
reduced_transaction_id_(ReduceTransactionId(transaction_id_)) {
RTC_DCHECK(IsValidTransactionId(transaction_id_));
}
StunMessage::~StunMessage() = default;
bool StunMessage::IsLegacy() const {
if (transaction_id_.size() == kStunLegacyTransactionIdLength)
return true;
RTC_DCHECK(transaction_id_.size() == kStunTransactionIdLength);
return false;
}
static bool DesignatedExpertRange(int attr_type) {
return (attr_type >= 0x4000 && attr_type <= 0x7FFF) ||
(attr_type >= 0xC000 && attr_type <= 0xFFFF);
}
void StunMessage::AddAttribute(std::unique_ptr<StunAttribute> attr) {
// Fail any attributes that aren't valid for this type of message,
// but allow any type for the range that in the RFC is reserved for
// the "designated experts".
if (!DesignatedExpertRange(attr->type())) {
RTC_DCHECK_EQ(attr->value_type(), GetAttributeValueType(attr->type()));
}
attr->SetOwner(this);
size_t attr_length = attr->length();
if (attr_length % 4 != 0) {
attr_length += (4 - (attr_length % 4));
}
length_ += static_cast<uint16_t>(attr_length + 4);
attrs_.push_back(std::move(attr));
}
std::unique_ptr<StunAttribute> StunMessage::RemoveAttribute(int type) {
std::unique_ptr<StunAttribute> attribute;
for (auto it = attrs_.rbegin(); it != attrs_.rend(); ++it) {
if ((*it)->type() == type) {
attribute = std::move(*it);
attrs_.erase(std::next(it).base());
break;
}
}
if (attribute) {
attribute->SetOwner(nullptr);
size_t attr_length = attribute->length();
if (attr_length % 4 != 0) {
attr_length += (4 - (attr_length % 4));
}
length_ -= static_cast<uint16_t>(attr_length + 4);
}
return attribute;
}
void StunMessage::ClearAttributes() {
for (auto it = attrs_.rbegin(); it != attrs_.rend(); ++it) {
(*it)->SetOwner(nullptr);
}
attrs_.clear();
length_ = 0;
}
std::vector<uint16_t> StunMessage::GetNonComprehendedAttributes() const {
std::vector<uint16_t> unknown_attributes;
for (auto& attr : attrs_) {
// "comprehension-required" range is 0x0000-0x7FFF.
if (attr->type() >= 0x0000 && attr->type() <= 0x7FFF &&
GetAttributeValueType(attr->type()) == STUN_VALUE_UNKNOWN) {
unknown_attributes.push_back(attr->type());
}
}
return unknown_attributes;
}
const StunAddressAttribute* StunMessage::GetAddress(int type) const {
switch (type) {
case STUN_ATTR_MAPPED_ADDRESS: {
// Return XOR-MAPPED-ADDRESS when MAPPED-ADDRESS attribute is
// missing.
const StunAttribute* mapped_address =
GetAttribute(STUN_ATTR_MAPPED_ADDRESS);
if (!mapped_address)
mapped_address = GetAttribute(STUN_ATTR_XOR_MAPPED_ADDRESS);
return reinterpret_cast<const StunAddressAttribute*>(mapped_address);
}
default:
return static_cast<const StunAddressAttribute*>(GetAttribute(type));
}
}
const StunUInt32Attribute* StunMessage::GetUInt32(int type) const {
return static_cast<const StunUInt32Attribute*>(GetAttribute(type));
}
const StunUInt64Attribute* StunMessage::GetUInt64(int type) const {
return static_cast<const StunUInt64Attribute*>(GetAttribute(type));
}
const StunByteStringAttribute* StunMessage::GetByteString(int type) const {
return static_cast<const StunByteStringAttribute*>(GetAttribute(type));
}
const StunUInt16ListAttribute* StunMessage::GetUInt16List(int type) const {
return static_cast<const StunUInt16ListAttribute*>(GetAttribute(type));
}
const StunErrorCodeAttribute* StunMessage::GetErrorCode() const {
return static_cast<const StunErrorCodeAttribute*>(
GetAttribute(STUN_ATTR_ERROR_CODE));
}
int StunMessage::GetErrorCodeValue() const {
const StunErrorCodeAttribute* error_attribute = GetErrorCode();
return error_attribute ? error_attribute->code() : STUN_ERROR_GLOBAL_FAILURE;
}
const StunUInt16ListAttribute* StunMessage::GetUnknownAttributes() const {
return static_cast<const StunUInt16ListAttribute*>(
GetAttribute(STUN_ATTR_UNKNOWN_ATTRIBUTES));
}
StunMessage::IntegrityStatus StunMessage::ValidateMessageIntegrity(
const std::string& password) {
RTC_DCHECK(integrity_ == IntegrityStatus::kNotSet)
<< "Usage error: Verification should only be done once";
password_ = password;
if (GetByteString(STUN_ATTR_MESSAGE_INTEGRITY)) {
if (ValidateMessageIntegrityOfType(
STUN_ATTR_MESSAGE_INTEGRITY, kStunMessageIntegritySize,
buffer_.c_str(), buffer_.size(), password)) {
integrity_ = IntegrityStatus::kIntegrityOk;
} else {
integrity_ = IntegrityStatus::kIntegrityBad;
}
} else if (GetByteString(STUN_ATTR_GOOG_MESSAGE_INTEGRITY_32)) {
if (ValidateMessageIntegrityOfType(
STUN_ATTR_GOOG_MESSAGE_INTEGRITY_32, kStunMessageIntegrity32Size,
buffer_.c_str(), buffer_.size(), password)) {
integrity_ = IntegrityStatus::kIntegrityOk;
} else {
integrity_ = IntegrityStatus::kIntegrityBad;
}
} else {
integrity_ = IntegrityStatus::kNoIntegrity;
}
// Log the result of integrity checking. See crbug.com/1177125 for background.
// Convert args to integer for the benefit of the macros.
int bucket_count = static_cast<int>(IntegrityStatus::kMaxValue) + 1;
int integrity = static_cast<int>(integrity_);
if (IsStunRequestType(type_)) {
RTC_HISTOGRAM_ENUMERATION("WebRTC.Stun.Integrity.Request", integrity,
bucket_count);
} else if (IsStunSuccessResponseType(type_)) {
RTC_HISTOGRAM_ENUMERATION("WebRTC.Stun.Integrity.Response", integrity,
bucket_count);
} else if (IsStunIndicationType(type_)) {
RTC_HISTOGRAM_ENUMERATION("WebRTC.Stun.Integrity.Indication", integrity,
bucket_count);
} else {
RTC_DCHECK(IsStunErrorResponseType(type_));
auto* error_attribute = GetErrorCode();
if (!error_attribute) {
RTC_HISTOGRAM_ENUMERATION(
"WebRTC.Stun.Integrity.ErrorResponse.NoErrorAttribute", integrity,
bucket_count);
} else {
switch (error_attribute->code()) {
case STUN_ERROR_TRY_ALTERNATE:
RTC_HISTOGRAM_ENUMERATION(
"WebRTC.Stun.Integrity.ErrorResponse.TryAlternate", integrity,
bucket_count);
break;
case STUN_ERROR_BAD_REQUEST:
RTC_HISTOGRAM_ENUMERATION(
"WebRTC.Stun.Integrity.ErrorResponse.BadRequest", integrity,
bucket_count);
break;
case STUN_ERROR_UNAUTHORIZED:
RTC_HISTOGRAM_ENUMERATION(
"WebRTC.Stun.Integrity.ErrorResponse.Unauthorized", integrity,
bucket_count);
break;
case STUN_ERROR_UNKNOWN_ATTRIBUTE:
RTC_HISTOGRAM_ENUMERATION(
"WebRTC.Stun.Integrity.ErrorResponse.UnknownAttribute", integrity,
bucket_count);
break;
case STUN_ERROR_STALE_NONCE:
RTC_HISTOGRAM_ENUMERATION(
"WebRTC.Stun.Integrity.ErrorResponse.StaleNonce", integrity,
bucket_count);
break;
case STUN_ERROR_SERVER_ERROR:
RTC_HISTOGRAM_ENUMERATION(
"WebRTC.Stun.Integrity.ErrorResponse.ServerError", integrity,
bucket_count);
break;
case STUN_ERROR_GLOBAL_FAILURE:
RTC_HISTOGRAM_ENUMERATION(
"WebRTC.Stun.Integrity.ErrorResponse.GlobalFailure", integrity,
bucket_count);
break;
default:
RTC_HISTOGRAM_ENUMERATION(
"WebRTC.Stun.Integrity.ErrorResponse.ErrorOther", integrity,
bucket_count);
break;
}
}
}
return integrity_;
}
StunMessage::IntegrityStatus StunMessage::RevalidateMessageIntegrity(
const std::string& password) {
RTC_LOG(LS_INFO) << "Message revalidation, old status was "
<< static_cast<int>(integrity_);
integrity_ = IntegrityStatus::kNotSet;
return ValidateMessageIntegrity(password);
}
bool StunMessage::ValidateMessageIntegrityForTesting(
const char* data,
size_t size,
const std::string& password) {
return ValidateMessageIntegrityOfType(STUN_ATTR_MESSAGE_INTEGRITY,
kStunMessageIntegritySize, data, size,
password);
}
bool StunMessage::ValidateMessageIntegrity32ForTesting(
const char* data,
size_t size,
const std::string& password) {
return ValidateMessageIntegrityOfType(STUN_ATTR_GOOG_MESSAGE_INTEGRITY_32,
kStunMessageIntegrity32Size, data, size,
password);
}
// Deprecated
bool StunMessage::ValidateMessageIntegrity(const char* data,
size_t size,
const std::string& password) {
return ValidateMessageIntegrityOfType(STUN_ATTR_MESSAGE_INTEGRITY,
kStunMessageIntegritySize, data, size,
password);
}
// Deprecated
bool StunMessage::ValidateMessageIntegrity32(const char* data,
size_t size,
const std::string& password) {
return ValidateMessageIntegrityOfType(STUN_ATTR_GOOG_MESSAGE_INTEGRITY_32,
kStunMessageIntegrity32Size, data, size,
password);
}
// Verifies a STUN message has a valid MESSAGE-INTEGRITY attribute, using the
// procedure outlined in RFC 5389, section 15.4.
bool StunMessage::ValidateMessageIntegrityOfType(int mi_attr_type,
size_t mi_attr_size,
const char* data,
size_t size,
const std::string& password) {
RTC_DCHECK(mi_attr_size <= kStunMessageIntegritySize);
// Verifying the size of the message.
if ((size % 4) != 0 || size < kStunHeaderSize) {
return false;
}
// Getting the message length from the STUN header.
uint16_t msg_length = rtc::GetBE16(&data[2]);
if (size != (msg_length + kStunHeaderSize)) {
return false;
}
// Finding Message Integrity attribute in stun message.
size_t current_pos = kStunHeaderSize;
bool has_message_integrity_attr = false;
while (current_pos + 4 <= size) {
uint16_t attr_type, attr_length;
// Getting attribute type and length.
attr_type = rtc::GetBE16(&data[current_pos]);
attr_length = rtc::GetBE16(&data[current_pos + sizeof(attr_type)]);
// If M-I, sanity check it, and break out.
if (attr_type == mi_attr_type) {
if (attr_length != mi_attr_size ||
current_pos + sizeof(attr_type) + sizeof(attr_length) + attr_length >
size) {
return false;
}
has_message_integrity_attr = true;
break;
}
// Otherwise, skip to the next attribute.
current_pos += sizeof(attr_type) + sizeof(attr_length) + attr_length;
if ((attr_length % 4) != 0) {
current_pos += (4 - (attr_length % 4));
}
}
if (!has_message_integrity_attr) {
return false;
}
// Getting length of the message to calculate Message Integrity.
size_t mi_pos = current_pos;
std::unique_ptr<char[]> temp_data(new char[current_pos]);
memcpy(temp_data.get(), data, current_pos);
if (size > mi_pos + kStunAttributeHeaderSize + mi_attr_size) {
// Stun message has other attributes after message integrity.
// Adjust the length parameter in stun message to calculate HMAC.
size_t extra_offset =
size - (mi_pos + kStunAttributeHeaderSize + mi_attr_size);
size_t new_adjusted_len = size - extra_offset - kStunHeaderSize;
// Writing new length of the STUN message @ Message Length in temp buffer.
// 0 1 2 3
// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// |0 0| STUN Message Type | Message Length |
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
rtc::SetBE16(temp_data.get() + 2, static_cast<uint16_t>(new_adjusted_len));
}
char hmac[kStunMessageIntegritySize];
size_t ret =
rtc::ComputeHmac(rtc::DIGEST_SHA_1, password.c_str(), password.size(),
temp_data.get(), mi_pos, hmac, sizeof(hmac));
RTC_DCHECK(ret == sizeof(hmac));
if (ret != sizeof(hmac)) {
return false;
}
// Comparing the calculated HMAC with the one present in the message.
return memcmp(data + current_pos + kStunAttributeHeaderSize, hmac,
mi_attr_size) == 0;
}
bool StunMessage::AddMessageIntegrity(absl::string_view password) {
return AddMessageIntegrityOfType(STUN_ATTR_MESSAGE_INTEGRITY,
kStunMessageIntegritySize, password);
}
bool StunMessage::AddMessageIntegrity32(absl::string_view password) {
return AddMessageIntegrityOfType(STUN_ATTR_GOOG_MESSAGE_INTEGRITY_32,
kStunMessageIntegrity32Size, password);
}
bool StunMessage::AddMessageIntegrityOfType(int attr_type,
size_t attr_size,
absl::string_view key) {
// Add the attribute with a dummy value. Since this is a known attribute, it
// can't fail.
RTC_DCHECK(attr_size <= kStunMessageIntegritySize);
auto msg_integrity_attr_ptr = std::make_unique<StunByteStringAttribute>(
attr_type, std::string(attr_size, '0'));
auto* msg_integrity_attr = msg_integrity_attr_ptr.get();
AddAttribute(std::move(msg_integrity_attr_ptr));
// Calculate the HMAC for the message.
ByteBufferWriter buf;
if (!Write(&buf))
return false;
int msg_len_for_hmac = static_cast<int>(
buf.Length() - kStunAttributeHeaderSize - msg_integrity_attr->length());
char hmac[kStunMessageIntegritySize];
size_t ret =
rtc::ComputeHmac(rtc::DIGEST_SHA_1, key.data(), key.size(), buf.Data(),
msg_len_for_hmac, hmac, sizeof(hmac));
RTC_DCHECK(ret == sizeof(hmac));
if (ret != sizeof(hmac)) {
RTC_LOG(LS_ERROR) << "HMAC computation failed. Message-Integrity "
"has dummy value.";
return false;
}
// Insert correct HMAC into the attribute.
msg_integrity_attr->CopyBytes(hmac, attr_size);
password_ = std::string(key);
integrity_ = IntegrityStatus::kIntegrityOk;
return true;
}
// Verifies a message is in fact a STUN message, by performing the checks
// outlined in RFC 5389, section 7.3, including the FINGERPRINT check detailed
// in section 15.5.
bool StunMessage::ValidateFingerprint(const char* data, size_t size) {
// Check the message length.
size_t fingerprint_attr_size =
kStunAttributeHeaderSize + StunUInt32Attribute::SIZE;
if (size % 4 != 0 || size < kStunHeaderSize + fingerprint_attr_size)
return false;
// Skip the rest if the magic cookie isn't present.
const char* magic_cookie =
data + kStunTransactionIdOffset - kStunMagicCookieLength;
if (rtc::GetBE32(magic_cookie) != kStunMagicCookie)
return false;
// Check the fingerprint type and length.
const char* fingerprint_attr_data = data + size - fingerprint_attr_size;
if (rtc::GetBE16(fingerprint_attr_data) != STUN_ATTR_FINGERPRINT ||
rtc::GetBE16(fingerprint_attr_data + sizeof(uint16_t)) !=
StunUInt32Attribute::SIZE)
return false;
// Check the fingerprint value.
uint32_t fingerprint =
rtc::GetBE32(fingerprint_attr_data + kStunAttributeHeaderSize);
return ((fingerprint ^ STUN_FINGERPRINT_XOR_VALUE) ==
rtc::ComputeCrc32(data, size - fingerprint_attr_size));
}
// static
std::string StunMessage::GenerateTransactionId() {
return rtc::CreateRandomString(kStunTransactionIdLength);
}
bool StunMessage::IsStunMethod(rtc::ArrayView<int> methods,
const char* data,
size_t size) {
// Check the message length.
if (size % 4 != 0 || size < kStunHeaderSize)
return false;
// Skip the rest if the magic cookie isn't present.
const char* magic_cookie =
data + kStunTransactionIdOffset - kStunMagicCookieLength;
if (rtc::GetBE32(magic_cookie) != kStunMagicCookie)
return false;
int method = rtc::GetBE16(data);
for (int m : methods) {
if (m == method) {
return true;
}
}
return false;
}
bool StunMessage::AddFingerprint() {
// Add the attribute with a dummy value. Since this is a known attribute,
// it can't fail.
auto fingerprint_attr_ptr =
std::make_unique<StunUInt32Attribute>(STUN_ATTR_FINGERPRINT, 0);
auto* fingerprint_attr = fingerprint_attr_ptr.get();
AddAttribute(std::move(fingerprint_attr_ptr));
// Calculate the CRC-32 for the message and insert it.
ByteBufferWriter buf;
if (!Write(&buf))
return false;
int msg_len_for_crc32 = static_cast<int>(
buf.Length() - kStunAttributeHeaderSize - fingerprint_attr->length());
uint32_t c = rtc::ComputeCrc32(buf.Data(), msg_len_for_crc32);
// Insert the correct CRC-32, XORed with a constant, into the attribute.
fingerprint_attr->SetValue(c ^ STUN_FINGERPRINT_XOR_VALUE);
return true;
}
bool StunMessage::Read(ByteBufferReader* buf) {
// Keep a copy of the buffer data around for later verification.
buffer_.assign(buf->Data(), buf->Length());
if (!buf->ReadUInt16(&type_)) {
return false;
}
if (type_ & 0x8000) {
// RTP and RTCP set the MSB of first byte, since first two bits are version,
// and version is always 2 (10). If set, this is not a STUN packet.
return false;
}
if (!buf->ReadUInt16(&length_)) {
return false;
}
std::string magic_cookie;
if (!buf->ReadString(&magic_cookie, kStunMagicCookieLength)) {
return false;
}
std::string transaction_id;
if (!buf->ReadString(&transaction_id, kStunTransactionIdLength)) {
return false;
}
uint32_t magic_cookie_int;
static_assert(sizeof(magic_cookie_int) == kStunMagicCookieLength,
"Integer size mismatch: magic_cookie_int and kStunMagicCookie");
std::memcpy(&magic_cookie_int, magic_cookie.data(), sizeof(magic_cookie_int));
if (rtc::NetworkToHost32(magic_cookie_int) != kStunMagicCookie) {
// If magic cookie is invalid it means that the peer implements
// RFC3489 instead of RFC5389.
transaction_id.insert(0, magic_cookie);
}
RTC_DCHECK(IsValidTransactionId(transaction_id));
transaction_id_ = transaction_id;
reduced_transaction_id_ = ReduceTransactionId(transaction_id_);
if (length_ != buf->Length()) {
return false;
}
attrs_.resize(0);
size_t rest = buf->Length() - length_;
while (buf->Length() > rest) {
uint16_t attr_type, attr_length;
if (!buf->ReadUInt16(&attr_type))
return false;
if (!buf->ReadUInt16(&attr_length))
return false;
std::unique_ptr<StunAttribute> attr(
CreateAttribute(attr_type, attr_length));
if (!attr) {
// Skip any unknown or malformed attributes.
if ((attr_length % 4) != 0) {
attr_length += (4 - (attr_length % 4));
}
if (!buf->Consume(attr_length)) {
return false;
}
} else {
if (!attr->Read(buf)) {
return false;
}
attrs_.push_back(std::move(attr));
}
}
RTC_DCHECK(buf->Length() == rest);
return true;
}
bool StunMessage::Write(ByteBufferWriter* buf) const {
buf->WriteUInt16(type_);
buf->WriteUInt16(length_);
if (!IsLegacy())
buf->WriteUInt32(stun_magic_cookie_);
buf->WriteString(transaction_id_);
for (const auto& attr : attrs_) {
buf->WriteUInt16(attr->type());
buf->WriteUInt16(static_cast<uint16_t>(attr->length()));
if (!attr->Write(buf)) {
return false;
}
}
return true;
}
StunMessage* StunMessage::CreateNew() const {
return new StunMessage();
}
void StunMessage::SetStunMagicCookie(uint32_t val) {
stun_magic_cookie_ = val;
}
void StunMessage::SetTransactionIdForTesting(absl::string_view transaction_id) {
RTC_DCHECK(IsValidTransactionId(transaction_id));
transaction_id_ = std::string(transaction_id);
reduced_transaction_id_ = ReduceTransactionId(transaction_id_);
}
StunAttributeValueType StunMessage::GetAttributeValueType(int type) const {
switch (type) {
case STUN_ATTR_MAPPED_ADDRESS:
return STUN_VALUE_ADDRESS;
case STUN_ATTR_USERNAME:
return STUN_VALUE_BYTE_STRING;
case STUN_ATTR_MESSAGE_INTEGRITY:
return STUN_VALUE_BYTE_STRING;
case STUN_ATTR_ERROR_CODE:
return STUN_VALUE_ERROR_CODE;
case STUN_ATTR_UNKNOWN_ATTRIBUTES:
return STUN_VALUE_UINT16_LIST;
case STUN_ATTR_REALM:
return STUN_VALUE_BYTE_STRING;
case STUN_ATTR_NONCE:
return STUN_VALUE_BYTE_STRING;
case STUN_ATTR_XOR_MAPPED_ADDRESS:
return STUN_VALUE_XOR_ADDRESS;
case STUN_ATTR_SOFTWARE:
return STUN_VALUE_BYTE_STRING;
case STUN_ATTR_ALTERNATE_SERVER:
return STUN_VALUE_ADDRESS;
case STUN_ATTR_FINGERPRINT:
return STUN_VALUE_UINT32;
case STUN_ATTR_RETRANSMIT_COUNT:
return STUN_VALUE_UINT32;
case STUN_ATTR_GOOG_LAST_ICE_CHECK_RECEIVED:
return STUN_VALUE_BYTE_STRING;
case STUN_ATTR_GOOG_MISC_INFO:
return STUN_VALUE_UINT16_LIST;
case STUN_ATTR_GOOG_DELTA:
return STUN_VALUE_BYTE_STRING;
case STUN_ATTR_GOOG_DELTA_ACK:
return STUN_VALUE_UINT64;
default:
return STUN_VALUE_UNKNOWN;
}
}
StunAttribute* StunMessage::CreateAttribute(int type, size_t length) /*const*/ {
StunAttributeValueType value_type = GetAttributeValueType(type);
if (value_type != STUN_VALUE_UNKNOWN) {
return StunAttribute::Create(value_type, type,
static_cast<uint16_t>(length), this);
} else if (DesignatedExpertRange(type)) {
// Read unknown attributes as STUN_VALUE_BYTE_STRING
return StunAttribute::Create(STUN_VALUE_BYTE_STRING, type,
static_cast<uint16_t>(length), this);
} else {
return NULL;
}
}
const StunAttribute* StunMessage::GetAttribute(int type) const {
for (const auto& attr : attrs_) {
if (attr->type() == type) {
return attr.get();
}
}
return NULL;
}
bool StunMessage::IsValidTransactionId(absl::string_view transaction_id) {
return transaction_id.size() == kStunTransactionIdLength ||
transaction_id.size() == kStunLegacyTransactionIdLength;
}
bool StunMessage::EqualAttributes(
const StunMessage* other,
std::function<bool(int type)> attribute_type_mask) const {
RTC_DCHECK(other != nullptr);
rtc::ByteBufferWriter tmp_buffer_ptr1;
rtc::ByteBufferWriter tmp_buffer_ptr2;
for (const auto& attr : attrs_) {
if (attribute_type_mask(attr->type())) {
const StunAttribute* other_attr = other->GetAttribute(attr->type());
if (other_attr == nullptr) {
return false;
}
tmp_buffer_ptr1.Clear();
tmp_buffer_ptr2.Clear();
attr->Write(&tmp_buffer_ptr1);
other_attr->Write(&tmp_buffer_ptr2);
if (tmp_buffer_ptr1.Length() != tmp_buffer_ptr2.Length()) {
return false;
}
if (memcmp(tmp_buffer_ptr1.Data(), tmp_buffer_ptr2.Data(),
tmp_buffer_ptr1.Length()) != 0) {
return false;
}
}
}
for (const auto& attr : other->attrs_) {
if (attribute_type_mask(attr->type())) {
const StunAttribute* own_attr = GetAttribute(attr->type());
if (own_attr == nullptr) {
return false;
}
// we have already compared all values...
}
}
return true;
}
// StunAttribute
StunAttribute::StunAttribute(uint16_t type, uint16_t length)
: type_(type), length_(length) {}
void StunAttribute::ConsumePadding(ByteBufferReader* buf) const {
int remainder = length_ % 4;
if (remainder > 0) {
buf->Consume(4 - remainder);
}
}
void StunAttribute::WritePadding(ByteBufferWriter* buf) const {
int remainder = length_ % 4;
if (remainder > 0) {
char zeroes[4] = {0};
buf->WriteBytes(zeroes, 4 - remainder);
}
}
StunAttribute* StunAttribute::Create(StunAttributeValueType value_type,
uint16_t type,
uint16_t length,
StunMessage* owner) {
switch (value_type) {
case STUN_VALUE_ADDRESS:
return new StunAddressAttribute(type, length);
case STUN_VALUE_XOR_ADDRESS:
return new StunXorAddressAttribute(type, length, owner);
case STUN_VALUE_UINT32:
return new StunUInt32Attribute(type);
case STUN_VALUE_UINT64:
return new StunUInt64Attribute(type);
case STUN_VALUE_BYTE_STRING:
return new StunByteStringAttribute(type, length);
case STUN_VALUE_ERROR_CODE:
return new StunErrorCodeAttribute(type, length);
case STUN_VALUE_UINT16_LIST:
return new StunUInt16ListAttribute(type, length);
default:
return NULL;
}
}
std::unique_ptr<StunAddressAttribute> StunAttribute::CreateAddress(
uint16_t type) {
return std::make_unique<StunAddressAttribute>(type, 0);
}
std::unique_ptr<StunXorAddressAttribute> StunAttribute::CreateXorAddress(
uint16_t type) {
return std::make_unique<StunXorAddressAttribute>(type, 0, nullptr);
}
std::unique_ptr<StunUInt64Attribute> StunAttribute::CreateUInt64(
uint16_t type) {
return std::make_unique<StunUInt64Attribute>(type);
}
std::unique_ptr<StunUInt32Attribute> StunAttribute::CreateUInt32(
uint16_t type) {
return std::make_unique<StunUInt32Attribute>(type);
}
std::unique_ptr<StunByteStringAttribute> StunAttribute::CreateByteString(
uint16_t type) {
return std::make_unique<StunByteStringAttribute>(type, 0);
}
std::unique_ptr<StunErrorCodeAttribute> StunAttribute::CreateErrorCode() {
return std::make_unique<StunErrorCodeAttribute>(
STUN_ATTR_ERROR_CODE, StunErrorCodeAttribute::MIN_SIZE);
}
std::unique_ptr<StunUInt16ListAttribute>
StunAttribute::CreateUInt16ListAttribute(uint16_t type) {
return std::make_unique<StunUInt16ListAttribute>(type, 0);
}
std::unique_ptr<StunUInt16ListAttribute>
StunAttribute::CreateUnknownAttributes() {
return std::make_unique<StunUInt16ListAttribute>(STUN_ATTR_UNKNOWN_ATTRIBUTES,
0);
}
StunAddressAttribute::StunAddressAttribute(uint16_t type,
const rtc::SocketAddress& addr)
: StunAttribute(type, 0) {
SetAddress(addr);
}
StunAddressAttribute::StunAddressAttribute(uint16_t type, uint16_t length)
: StunAttribute(type, length) {}
StunAttributeValueType StunAddressAttribute::value_type() const {
return STUN_VALUE_ADDRESS;
}
bool StunAddressAttribute::Read(ByteBufferReader* buf) {
uint8_t dummy;
if (!buf->ReadUInt8(&dummy))
return false;
uint8_t stun_family;
if (!buf->ReadUInt8(&stun_family)) {
return false;
}
uint16_t port;
if (!buf->ReadUInt16(&port))
return false;
if (stun_family == STUN_ADDRESS_IPV4) {
in_addr v4addr;
if (length() != SIZE_IP4) {
return false;
}
if (!buf->ReadBytes(rtc::MakeArrayView(reinterpret_cast<uint8_t*>(&v4addr),
sizeof(v4addr)))) {
return false;
}
rtc::IPAddress ipaddr(v4addr);
SetAddress(rtc::SocketAddress(ipaddr, port));
} else if (stun_family == STUN_ADDRESS_IPV6) {
in6_addr v6addr;
if (length() != SIZE_IP6) {
return false;
}
if (!buf->ReadBytes(rtc::MakeArrayView(reinterpret_cast<uint8_t*>(&v6addr),
sizeof(v6addr)))) {
return false;
}
rtc::IPAddress ipaddr(v6addr);
SetAddress(rtc::SocketAddress(ipaddr, port));
} else {
return false;
}
return true;
}
bool StunAddressAttribute::Write(ByteBufferWriter* buf) const {
StunAddressFamily address_family = family();
if (address_family == STUN_ADDRESS_UNDEF) {
RTC_LOG(LS_ERROR) << "Error writing address attribute: unknown family.";
return false;
}
buf->WriteUInt8(0);
buf->WriteUInt8(address_family);
buf->WriteUInt16(address_.port());
switch (address_.family()) {
case AF_INET: {
in_addr v4addr = address_.ipaddr().ipv4_address();
buf->WriteBytes(reinterpret_cast<char*>(&v4addr), sizeof(v4addr));
break;
}
case AF_INET6: {
in6_addr v6addr = address_.ipaddr().ipv6_address();
buf->WriteBytes(reinterpret_cast<char*>(&v6addr), sizeof(v6addr));
break;
}
}
return true;
}
StunXorAddressAttribute::StunXorAddressAttribute(uint16_t type,
const rtc::SocketAddress& addr)
: StunAddressAttribute(type, addr), owner_(NULL) {}
StunXorAddressAttribute::StunXorAddressAttribute(uint16_t type,
uint16_t length,
StunMessage* owner)
: StunAddressAttribute(type, length), owner_(owner) {}
StunAttributeValueType StunXorAddressAttribute::value_type() const {
return STUN_VALUE_XOR_ADDRESS;
}
void StunXorAddressAttribute::SetOwner(StunMessage* owner) {
owner_ = owner;
}
rtc::IPAddress StunXorAddressAttribute::GetXoredIP() const {
if (owner_) {
rtc::IPAddress ip = ipaddr();
switch (ip.family()) {
case AF_INET: {
in_addr v4addr = ip.ipv4_address();
v4addr.s_addr =
(v4addr.s_addr ^ rtc::HostToNetwork32(kStunMagicCookie));
return rtc::IPAddress(v4addr);
}
case AF_INET6: {
in6_addr v6addr = ip.ipv6_address();
const std::string& transaction_id = owner_->transaction_id();
if (transaction_id.length() == kStunTransactionIdLength) {
uint32_t transactionid_as_ints[3];
memcpy(&transactionid_as_ints[0], transaction_id.c_str(),
transaction_id.length());
uint32_t* ip_as_ints = reinterpret_cast<uint32_t*>(&v6addr.s6_addr);
// Transaction ID is in network byte order, but magic cookie
// is stored in host byte order.
ip_as_ints[0] =
(ip_as_ints[0] ^ rtc::HostToNetwork32(kStunMagicCookie));
ip_as_ints[1] = (ip_as_ints[1] ^ transactionid_as_ints[0]);
ip_as_ints[2] = (ip_as_ints[2] ^ transactionid_as_ints[1]);
ip_as_ints[3] = (ip_as_ints[3] ^ transactionid_as_ints[2]);
return rtc::IPAddress(v6addr);
}
break;
}
}
}
// Invalid ip family or transaction ID, or missing owner.
// Return an AF_UNSPEC address.
return rtc::IPAddress();
}
bool StunXorAddressAttribute::Read(ByteBufferReader* buf) {
if (!StunAddressAttribute::Read(buf))
return false;
uint16_t xoredport = port() ^ (kStunMagicCookie >> 16);
rtc::IPAddress xored_ip = GetXoredIP();
SetAddress(rtc::SocketAddress(xored_ip, xoredport));
return true;
}
bool StunXorAddressAttribute::Write(ByteBufferWriter* buf) const {
StunAddressFamily address_family = family();
if (address_family == STUN_ADDRESS_UNDEF) {
RTC_LOG(LS_ERROR) << "Error writing xor-address attribute: unknown family.";
return false;
}
rtc::IPAddress xored_ip = GetXoredIP();
if (xored_ip.family() == AF_UNSPEC) {
return false;
}
buf->WriteUInt8(0);
buf->WriteUInt8(family());
buf->WriteUInt16(port() ^ (kStunMagicCookie >> 16));
switch (xored_ip.family()) {
case AF_INET: {
in_addr v4addr = xored_ip.ipv4_address();
buf->WriteBytes(reinterpret_cast<const char*>(&v4addr), sizeof(v4addr));
break;
}
case AF_INET6: {
in6_addr v6addr = xored_ip.ipv6_address();
buf->WriteBytes(reinterpret_cast<const char*>(&v6addr), sizeof(v6addr));
break;
}
}
return true;
}
StunUInt32Attribute::StunUInt32Attribute(uint16_t type, uint32_t value)
: StunAttribute(type, SIZE), bits_(value) {}
StunUInt32Attribute::StunUInt32Attribute(uint16_t type)
: StunAttribute(type, SIZE), bits_(0) {}
StunAttributeValueType StunUInt32Attribute::value_type() const {
return STUN_VALUE_UINT32;
}
bool StunUInt32Attribute::GetBit(size_t index) const {
RTC_DCHECK(index < 32);
return static_cast<bool>((bits_ >> index) & 0x1);
}
void StunUInt32Attribute::SetBit(size_t index, bool value) {
RTC_DCHECK(index < 32);
bits_ &= ~(1 << index);
bits_ |= value ? (1 << index) : 0;
}
bool StunUInt32Attribute::Read(ByteBufferReader* buf) {
if (length() != SIZE || !buf->ReadUInt32(&bits_))
return false;
return true;
}
bool StunUInt32Attribute::Write(ByteBufferWriter* buf) const {
buf->WriteUInt32(bits_);
return true;
}
StunUInt64Attribute::StunUInt64Attribute(uint16_t type, uint64_t value)
: StunAttribute(type, SIZE), bits_(value) {}
StunUInt64Attribute::StunUInt64Attribute(uint16_t type)
: StunAttribute(type, SIZE), bits_(0) {}
StunAttributeValueType StunUInt64Attribute::value_type() const {
return STUN_VALUE_UINT64;
}
bool StunUInt64Attribute::Read(ByteBufferReader* buf) {
if (length() != SIZE || !buf->ReadUInt64(&bits_))
return false;
return true;
}
bool StunUInt64Attribute::Write(ByteBufferWriter* buf) const {
buf->WriteUInt64(bits_);
return true;
}
StunByteStringAttribute::StunByteStringAttribute(uint16_t type)
: StunAttribute(type, 0), bytes_(NULL) {}
StunByteStringAttribute::StunByteStringAttribute(uint16_t type,
absl::string_view str)
: StunAttribute(type, 0), bytes_(NULL) {
CopyBytes(str);
}
StunByteStringAttribute::StunByteStringAttribute(uint16_t type,
const void* bytes,
size_t length)
: StunAttribute(type, 0), bytes_(NULL) {
CopyBytes(bytes, length);
}
StunByteStringAttribute::StunByteStringAttribute(uint16_t type, uint16_t length)
: StunAttribute(type, length), bytes_(NULL) {}
StunByteStringAttribute::~StunByteStringAttribute() {
delete[] bytes_;
}
StunAttributeValueType StunByteStringAttribute::value_type() const {
return STUN_VALUE_BYTE_STRING;
}
void StunByteStringAttribute::CopyBytes(absl::string_view bytes) {
uint8_t* new_bytes = new uint8_t[bytes.size()];
memcpy(new_bytes, bytes.data(), bytes.size());
SetBytes(new_bytes, bytes.size());
}
void StunByteStringAttribute::CopyBytes(const void* bytes, size_t length) {
uint8_t* new_bytes = new uint8_t[length];
memcpy(new_bytes, bytes, length);
SetBytes(new_bytes, length);
}
uint8_t StunByteStringAttribute::GetByte(size_t index) const {
RTC_DCHECK(bytes_ != NULL);
RTC_DCHECK(index < length());
return bytes_[index];
}
void StunByteStringAttribute::SetByte(size_t index, uint8_t value) {
RTC_DCHECK(bytes_ != NULL);
RTC_DCHECK(index < length());
bytes_[index] = value;
}
bool StunByteStringAttribute::Read(ByteBufferReader* buf) {
bytes_ = new uint8_t[length()];
if (!buf->ReadBytes(rtc::ArrayView<uint8_t>(bytes_, length()))) {
return false;
}
ConsumePadding(buf);
return true;
}
bool StunByteStringAttribute::Write(ByteBufferWriter* buf) const {
// Check that length is legal according to specs
if (!LengthValid(type(), length())) {
return false;
}
buf->WriteBytes(reinterpret_cast<const char*>(bytes_), length());
WritePadding(buf);
return true;
}
void StunByteStringAttribute::SetBytes(uint8_t* bytes, size_t length) {
delete[] bytes_;
bytes_ = bytes;
SetLength(static_cast<uint16_t>(length));
}
const uint16_t StunErrorCodeAttribute::MIN_SIZE = 4;
StunErrorCodeAttribute::StunErrorCodeAttribute(uint16_t type,
int code,
const std::string& reason)
: StunAttribute(type, 0) {
SetCode(code);
SetReason(reason);
}
StunErrorCodeAttribute::StunErrorCodeAttribute(uint16_t type, uint16_t length)
: StunAttribute(type, length), class_(0), number_(0) {}
StunErrorCodeAttribute::~StunErrorCodeAttribute() {}
StunAttributeValueType StunErrorCodeAttribute::value_type() const {
return STUN_VALUE_ERROR_CODE;
}
int StunErrorCodeAttribute::code() const {
return class_ * 100 + number_;
}
void StunErrorCodeAttribute::SetCode(int code) {
class_ = static_cast<uint8_t>(code / 100);
number_ = static_cast<uint8_t>(code % 100);
}
void StunErrorCodeAttribute::SetReason(const std::string& reason) {
SetLength(MIN_SIZE + static_cast<uint16_t>(reason.size()));
reason_ = reason;
}
bool StunErrorCodeAttribute::Read(ByteBufferReader* buf) {
uint32_t val;
if (length() < MIN_SIZE || !buf->ReadUInt32(&val))
return false;
if ((val >> 11) != 0)
RTC_LOG(LS_ERROR) << "error-code bits not zero";
class_ = ((val >> 8) & 0x7);
number_ = (val & 0xff);
if (!buf->ReadString(&reason_, length() - 4))
return false;
ConsumePadding(buf);
return true;
}
bool StunErrorCodeAttribute::Write(ByteBufferWriter* buf) const {
buf->WriteUInt32(class_ << 8 | number_);
buf->WriteString(reason_);
WritePadding(buf);
return true;
}
StunUInt16ListAttribute::StunUInt16ListAttribute(uint16_t type, uint16_t length)
: StunAttribute(type, length) {
attr_types_ = new std::vector<uint16_t>();
}
StunUInt16ListAttribute::~StunUInt16ListAttribute() {
delete attr_types_;
}
StunAttributeValueType StunUInt16ListAttribute::value_type() const {
return STUN_VALUE_UINT16_LIST;
}
size_t StunUInt16ListAttribute::Size() const {
return attr_types_->size();
}
uint16_t StunUInt16ListAttribute::GetType(int index) const {
return (*attr_types_)[index];
}
void StunUInt16ListAttribute::SetType(int index, uint16_t value) {
(*attr_types_)[index] = value;
}
void StunUInt16ListAttribute::AddType(uint16_t value) {
attr_types_->push_back(value);
SetLength(static_cast<uint16_t>(attr_types_->size() * 2));
}
void StunUInt16ListAttribute::AddTypeAtIndex(uint16_t index, uint16_t value) {
if (attr_types_->size() < static_cast<size_t>(index + 1)) {
attr_types_->resize(index + 1);
}
(*attr_types_)[index] = value;
SetLength(static_cast<uint16_t>(attr_types_->size() * 2));
}
bool StunUInt16ListAttribute::Read(ByteBufferReader* buf) {
if (length() % 2) {
return false;
}
for (size_t i = 0; i < length() / 2; i++) {
uint16_t attr;
if (!buf->ReadUInt16(&attr))
return false;
attr_types_->push_back(attr);
}
// Padding of these attributes is done in RFC 5389 style. This is
// slightly different from RFC3489, but it shouldn't be important.
// RFC3489 pads out to a 32 bit boundary by duplicating one of the
// entries in the list (not necessarily the last one - it's unspecified).
// RFC5389 pads on the end, and the bytes are always ignored.
ConsumePadding(buf);
return true;
}
bool StunUInt16ListAttribute::Write(ByteBufferWriter* buf) const {
for (size_t i = 0; i < attr_types_->size(); ++i) {
buf->WriteUInt16((*attr_types_)[i]);
}
WritePadding(buf);
return true;
}
std::string StunMethodToString(int msg_type) {
switch (msg_type) {
case STUN_BINDING_REQUEST:
return "STUN BINDING request";
case STUN_BINDING_INDICATION:
return "STUN BINDING indication";
case STUN_BINDING_RESPONSE:
return "STUN BINDING response";
case STUN_BINDING_ERROR_RESPONSE:
return "STUN BINDING error response";
case GOOG_PING_REQUEST:
return "GOOG PING request";
case GOOG_PING_RESPONSE:
return "GOOG PING response";
case GOOG_PING_ERROR_RESPONSE:
return "GOOG PING error response";
case STUN_ALLOCATE_REQUEST:
return "TURN ALLOCATE request";
case STUN_ALLOCATE_RESPONSE:
return "TURN ALLOCATE response";
case STUN_ALLOCATE_ERROR_RESPONSE:
return "TURN ALLOCATE error response";
case TURN_REFRESH_REQUEST:
return "TURN REFRESH request";
case TURN_REFRESH_RESPONSE:
return "TURN REFRESH response";
case TURN_REFRESH_ERROR_RESPONSE:
return "TURN REFRESH error response";
case TURN_SEND_INDICATION:
return "TURN SEND INDICATION";
case TURN_DATA_INDICATION:
return "TURN DATA INDICATION";
case TURN_CREATE_PERMISSION_REQUEST:
return "TURN CREATE PERMISSION request";
case TURN_CREATE_PERMISSION_RESPONSE:
return "TURN CREATE PERMISSION response";
case TURN_CREATE_PERMISSION_ERROR_RESPONSE:
return "TURN CREATE PERMISSION error response";
case TURN_CHANNEL_BIND_REQUEST:
return "TURN CHANNEL BIND request";
case TURN_CHANNEL_BIND_RESPONSE:
return "TURN CHANNEL BIND response";
case TURN_CHANNEL_BIND_ERROR_RESPONSE:
return "TURN CHANNEL BIND error response";
default:
return "UNKNOWN<" + std::to_string(msg_type) + ">";
}
}
int GetStunSuccessResponseType(int req_type) {
return IsStunRequestType(req_type) ? (req_type | 0x100) : -1;
}
int GetStunErrorResponseType(int req_type) {
return IsStunRequestType(req_type) ? (req_type | 0x110) : -1;
}
bool IsStunRequestType(int msg_type) {
return ((msg_type & kStunTypeMask) == 0x000);
}
bool IsStunIndicationType(int msg_type) {
return ((msg_type & kStunTypeMask) == 0x010);
}
bool IsStunSuccessResponseType(int msg_type) {
return ((msg_type & kStunTypeMask) == 0x100);
}
bool IsStunErrorResponseType(int msg_type) {
return ((msg_type & kStunTypeMask) == 0x110);
}
bool ComputeStunCredentialHash(const std::string& username,
const std::string& realm,
const std::string& password,
std::string* hash) {
// http://tools.ietf.org/html/rfc5389#section-15.4
// long-term credentials will be calculated using the key and key is
// key = MD5(username ":" realm ":" SASLprep(password))
std::string input = username;
input += ':';
input += realm;
input += ':';
input += password;
char digest[rtc::MessageDigest::kMaxSize];
size_t size = rtc::ComputeDigest(rtc::DIGEST_MD5, input.c_str(), input.size(),
digest, sizeof(digest));
if (size == 0) {
return false;
}
*hash = std::string(digest, size);
return true;
}
std::unique_ptr<StunAttribute> CopyStunAttribute(
const StunAttribute& attribute,
rtc::ByteBufferWriter* tmp_buffer_ptr) {
ByteBufferWriter tmpBuffer;
if (tmp_buffer_ptr == nullptr) {
tmp_buffer_ptr = &tmpBuffer;
}
std::unique_ptr<StunAttribute> copy(StunAttribute::Create(
attribute.value_type(), attribute.type(),
static_cast<uint16_t>(attribute.length()), nullptr));
if (!copy) {
return nullptr;
}
tmp_buffer_ptr->Clear();
if (!attribute.Write(tmp_buffer_ptr)) {
return nullptr;
}
rtc::ByteBufferReader reader(*tmp_buffer_ptr);
if (!copy->Read(&reader)) {
return nullptr;
}
return copy;
}
StunAttributeValueType RelayMessage::GetAttributeValueType(int type) const {
switch (type) {
case STUN_ATTR_LIFETIME:
return STUN_VALUE_UINT32;
case STUN_ATTR_MAGIC_COOKIE:
return STUN_VALUE_BYTE_STRING;
case STUN_ATTR_BANDWIDTH:
return STUN_VALUE_UINT32;
case STUN_ATTR_DESTINATION_ADDRESS:
return STUN_VALUE_ADDRESS;
case STUN_ATTR_SOURCE_ADDRESS2:
return STUN_VALUE_ADDRESS;
case STUN_ATTR_DATA:
return STUN_VALUE_BYTE_STRING;
case STUN_ATTR_OPTIONS:
return STUN_VALUE_UINT32;
default:
return StunMessage::GetAttributeValueType(type);
}
}
StunMessage* RelayMessage::CreateNew() const {
return new RelayMessage();
}
StunAttributeValueType TurnMessage::GetAttributeValueType(int type) const {
switch (type) {
case STUN_ATTR_CHANNEL_NUMBER:
return STUN_VALUE_UINT32;
case STUN_ATTR_TURN_LIFETIME:
return STUN_VALUE_UINT32;
case STUN_ATTR_XOR_PEER_ADDRESS:
return STUN_VALUE_XOR_ADDRESS;
case STUN_ATTR_DATA:
return STUN_VALUE_BYTE_STRING;
case STUN_ATTR_XOR_RELAYED_ADDRESS:
return STUN_VALUE_XOR_ADDRESS;
case STUN_ATTR_EVEN_PORT:
return STUN_VALUE_BYTE_STRING;
case STUN_ATTR_REQUESTED_TRANSPORT:
return STUN_VALUE_UINT32;
case STUN_ATTR_DONT_FRAGMENT:
return STUN_VALUE_BYTE_STRING;
case STUN_ATTR_RESERVATION_TOKEN:
return STUN_VALUE_BYTE_STRING;
default:
return StunMessage::GetAttributeValueType(type);
}
}
StunMessage* TurnMessage::CreateNew() const {
return new TurnMessage();
}
StunAttributeValueType IceMessage::GetAttributeValueType(int type) const {
switch (type) {
case STUN_ATTR_PRIORITY:
case STUN_ATTR_GOOG_NETWORK_INFO:
case STUN_ATTR_NOMINATION:
return STUN_VALUE_UINT32;
case STUN_ATTR_USE_CANDIDATE:
return STUN_VALUE_BYTE_STRING;
case STUN_ATTR_ICE_CONTROLLED:
return STUN_VALUE_UINT64;
case STUN_ATTR_ICE_CONTROLLING:
return STUN_VALUE_UINT64;
default:
return StunMessage::GetAttributeValueType(type);
}
}
StunMessage* IceMessage::CreateNew() const {
return new IceMessage();
}
std::unique_ptr<StunMessage> StunMessage::Clone() const {
std::unique_ptr<StunMessage> copy(CreateNew());
if (!copy) {
return nullptr;
}
rtc::ByteBufferWriter buf;
if (!Write(&buf)) {
return nullptr;
}
rtc::ByteBufferReader reader(buf);
if (!copy->Read(&reader)) {
return nullptr;
}
return copy;
}
} // namespace cricket