blob: 45c2ba40cd3cf9a4d5245d335b925dd86eae49a8 [file] [log] [blame]
// Copyright (c) 2012 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/quic/quic_utils.h"
#include <ctype.h>
#include <stdint.h>
#include <algorithm>
#include <vector>
#include "base/containers/adapters.h"
#include "base/logging.h"
#include "base/strings/string_number_conversions.h"
#include "base/strings/string_split.h"
#include "base/strings/stringprintf.h"
#include "net/base/ip_address.h"
#include "net/quic/quic_flags.h"
#include "net/quic/quic_write_blocked_list.h"
using base::StringPiece;
using std::string;
namespace net {
namespace {
// We know that >= GCC 4.8 and Clang have a __uint128_t intrinsic. Other
// compilers don't necessarily, notably MSVC.
#if defined(__x86_64__) && \
((defined(__GNUC__) && \
(__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 8))) || \
defined(__clang__))
#define QUIC_UTIL_HAS_UINT128 1
#endif
#ifdef QUIC_UTIL_HAS_UINT128
uint128 IncrementalHashFast(uint128 uhash, const char* data, size_t len) {
// This code ends up faster than the naive implementation for 2 reasons:
// 1. uint128 from base/int128.h is sufficiently complicated that the compiler
// cannot transform the multiplication by kPrime into a shift-multiply-add;
// it has go through all of the instructions for a 128-bit multiply.
// 2. Because there are so fewer instructions (around 13), the hot loop fits
// nicely in the instruction queue of many Intel CPUs.
// kPrime = 309485009821345068724781371
static const __uint128_t kPrime =
(static_cast<__uint128_t>(16777216) << 64) + 315;
__uint128_t xhash = (static_cast<__uint128_t>(Uint128High64(uhash)) << 64) +
Uint128Low64(uhash);
const uint8_t* octets = reinterpret_cast<const uint8_t*>(data);
for (size_t i = 0; i < len; ++i) {
xhash = (xhash ^ octets[i]) * kPrime;
}
return uint128(static_cast<uint64_t>(xhash >> 64),
static_cast<uint64_t>(xhash & UINT64_C(0xFFFFFFFFFFFFFFFF)));
}
#endif
#ifndef QUIC_UTIL_HAS_UINT128
// Slow implementation of IncrementalHash. In practice, only used by Chromium.
uint128 IncrementalHashSlow(uint128 hash, const char* data, size_t len) {
// kPrime = 309485009821345068724781371
static const uint128 kPrime(16777216, 315);
const uint8_t* octets = reinterpret_cast<const uint8_t*>(data);
for (size_t i = 0; i < len; ++i) {
hash = hash ^ uint128(0, octets[i]);
hash = hash * kPrime;
}
return hash;
}
#endif
uint128 IncrementalHash(uint128 hash, const char* data, size_t len) {
#ifdef QUIC_UTIL_HAS_UINT128
return IncrementalHashFast(hash, data, len);
#else
return IncrementalHashSlow(hash, data, len);
#endif
}
bool IsInitializedIPEndPoint(const IPEndPoint& address) {
return address.address().IsValid();
}
} // namespace
// static
uint64_t QuicUtils::FNV1a_64_Hash(const char* data, int len) {
static const uint64_t kOffset = UINT64_C(14695981039346656037);
static const uint64_t kPrime = UINT64_C(1099511628211);
const uint8_t* octets = reinterpret_cast<const uint8_t*>(data);
uint64_t hash = kOffset;
for (int i = 0; i < len; ++i) {
hash = hash ^ octets[i];
hash = hash * kPrime;
}
return hash;
}
// static
uint128 QuicUtils::FNV1a_128_Hash(const char* data, int len) {
return FNV1a_128_Hash_Two(data, len, nullptr, 0);
}
// static
uint128 QuicUtils::FNV1a_128_Hash_Two(const char* data1,
int len1,
const char* data2,
int len2) {
// The two constants are defined as part of the hash algorithm.
// see http://www.isthe.com/chongo/tech/comp/fnv/
// kOffset = 144066263297769815596495629667062367629
const uint128 kOffset(UINT64_C(7809847782465536322),
UINT64_C(7113472399480571277));
uint128 hash = IncrementalHash(kOffset, data1, len1);
if (data2 == nullptr) {
return hash;
}
return IncrementalHash(hash, data2, len2);
}
// static
bool QuicUtils::FindMutualTag(const QuicTagVector& our_tags_vector,
const QuicTag* their_tags,
size_t num_their_tags,
Priority priority,
QuicTag* out_result,
size_t* out_index) {
if (our_tags_vector.empty()) {
return false;
}
const size_t num_our_tags = our_tags_vector.size();
const QuicTag* our_tags = &our_tags_vector[0];
size_t num_priority_tags, num_inferior_tags;
const QuicTag* priority_tags;
const QuicTag* inferior_tags;
if (priority == LOCAL_PRIORITY) {
num_priority_tags = num_our_tags;
priority_tags = our_tags;
num_inferior_tags = num_their_tags;
inferior_tags = their_tags;
} else {
num_priority_tags = num_their_tags;
priority_tags = their_tags;
num_inferior_tags = num_our_tags;
inferior_tags = our_tags;
}
for (size_t i = 0; i < num_priority_tags; i++) {
for (size_t j = 0; j < num_inferior_tags; j++) {
if (priority_tags[i] == inferior_tags[j]) {
*out_result = priority_tags[i];
if (out_index) {
if (priority == LOCAL_PRIORITY) {
*out_index = j;
} else {
*out_index = i;
}
}
return true;
}
}
}
return false;
}
// static
void QuicUtils::SerializeUint128Short(uint128 v, uint8_t* out) {
const uint64_t lo = Uint128Low64(v);
const uint64_t hi = Uint128High64(v);
// This assumes that the system is little-endian.
memcpy(out, &lo, sizeof(lo));
memcpy(out + sizeof(lo), &hi, sizeof(hi) / 2);
}
#define RETURN_STRING_LITERAL(x) \
case x: \
return #x;
// static
const char* QuicUtils::StreamErrorToString(QuicRstStreamErrorCode error) {
switch (error) {
RETURN_STRING_LITERAL(QUIC_STREAM_NO_ERROR);
RETURN_STRING_LITERAL(QUIC_STREAM_CONNECTION_ERROR);
RETURN_STRING_LITERAL(QUIC_ERROR_PROCESSING_STREAM);
RETURN_STRING_LITERAL(QUIC_MULTIPLE_TERMINATION_OFFSETS);
RETURN_STRING_LITERAL(QUIC_BAD_APPLICATION_PAYLOAD);
RETURN_STRING_LITERAL(QUIC_STREAM_PEER_GOING_AWAY);
RETURN_STRING_LITERAL(QUIC_STREAM_CANCELLED);
RETURN_STRING_LITERAL(QUIC_RST_ACKNOWLEDGEMENT);
RETURN_STRING_LITERAL(QUIC_REFUSED_STREAM);
RETURN_STRING_LITERAL(QUIC_STREAM_LAST_ERROR);
RETURN_STRING_LITERAL(QUIC_INVALID_PROMISE_URL);
RETURN_STRING_LITERAL(QUIC_UNAUTHORIZED_PROMISE_URL);
RETURN_STRING_LITERAL(QUIC_DUPLICATE_PROMISE_URL);
RETURN_STRING_LITERAL(QUIC_PROMISE_VARY_MISMATCH);
RETURN_STRING_LITERAL(QUIC_INVALID_PROMISE_METHOD);
}
// Return a default value so that we return this when |error| doesn't match
// any of the QuicRstStreamErrorCodes. This can happen when the RstStream
// frame sent by the peer (attacker) has invalid error code.
return "INVALID_RST_STREAM_ERROR_CODE";
}
// static
const char* QuicUtils::ErrorToString(QuicErrorCode error) {
switch (error) {
RETURN_STRING_LITERAL(QUIC_NO_ERROR);
RETURN_STRING_LITERAL(QUIC_INTERNAL_ERROR);
RETURN_STRING_LITERAL(QUIC_STREAM_DATA_AFTER_TERMINATION);
RETURN_STRING_LITERAL(QUIC_INVALID_PACKET_HEADER);
RETURN_STRING_LITERAL(QUIC_INVALID_FRAME_DATA);
RETURN_STRING_LITERAL(QUIC_MISSING_PAYLOAD);
RETURN_STRING_LITERAL(QUIC_INVALID_FEC_DATA);
RETURN_STRING_LITERAL(QUIC_INVALID_STREAM_DATA);
RETURN_STRING_LITERAL(QUIC_OVERLAPPING_STREAM_DATA);
RETURN_STRING_LITERAL(QUIC_UNENCRYPTED_STREAM_DATA);
RETURN_STRING_LITERAL(QUIC_INVALID_RST_STREAM_DATA);
RETURN_STRING_LITERAL(QUIC_INVALID_CONNECTION_CLOSE_DATA);
RETURN_STRING_LITERAL(QUIC_INVALID_GOAWAY_DATA);
RETURN_STRING_LITERAL(QUIC_INVALID_WINDOW_UPDATE_DATA);
RETURN_STRING_LITERAL(QUIC_INVALID_BLOCKED_DATA);
RETURN_STRING_LITERAL(QUIC_INVALID_STOP_WAITING_DATA);
RETURN_STRING_LITERAL(QUIC_INVALID_PATH_CLOSE_DATA);
RETURN_STRING_LITERAL(QUIC_INVALID_ACK_DATA);
RETURN_STRING_LITERAL(QUIC_INVALID_VERSION_NEGOTIATION_PACKET);
RETURN_STRING_LITERAL(QUIC_INVALID_PUBLIC_RST_PACKET);
RETURN_STRING_LITERAL(QUIC_DECRYPTION_FAILURE);
RETURN_STRING_LITERAL(QUIC_ENCRYPTION_FAILURE);
RETURN_STRING_LITERAL(QUIC_PACKET_TOO_LARGE);
RETURN_STRING_LITERAL(QUIC_PEER_GOING_AWAY);
RETURN_STRING_LITERAL(QUIC_HANDSHAKE_FAILED);
RETURN_STRING_LITERAL(QUIC_CRYPTO_TAGS_OUT_OF_ORDER);
RETURN_STRING_LITERAL(QUIC_CRYPTO_TOO_MANY_ENTRIES);
RETURN_STRING_LITERAL(QUIC_CRYPTO_TOO_MANY_REJECTS);
RETURN_STRING_LITERAL(QUIC_CRYPTO_INVALID_VALUE_LENGTH)
RETURN_STRING_LITERAL(QUIC_CRYPTO_MESSAGE_AFTER_HANDSHAKE_COMPLETE);
RETURN_STRING_LITERAL(QUIC_CRYPTO_INTERNAL_ERROR);
RETURN_STRING_LITERAL(QUIC_CRYPTO_VERSION_NOT_SUPPORTED);
RETURN_STRING_LITERAL(QUIC_CRYPTO_HANDSHAKE_STATELESS_REJECT);
RETURN_STRING_LITERAL(QUIC_CRYPTO_NO_SUPPORT);
RETURN_STRING_LITERAL(QUIC_INVALID_CRYPTO_MESSAGE_TYPE);
RETURN_STRING_LITERAL(QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER);
RETURN_STRING_LITERAL(QUIC_CRYPTO_MESSAGE_PARAMETER_NOT_FOUND);
RETURN_STRING_LITERAL(QUIC_CRYPTO_MESSAGE_PARAMETER_NO_OVERLAP);
RETURN_STRING_LITERAL(QUIC_CRYPTO_MESSAGE_INDEX_NOT_FOUND);
RETURN_STRING_LITERAL(QUIC_INVALID_STREAM_ID);
RETURN_STRING_LITERAL(QUIC_INVALID_PRIORITY);
RETURN_STRING_LITERAL(QUIC_TOO_MANY_OPEN_STREAMS);
RETURN_STRING_LITERAL(QUIC_PUBLIC_RESET);
RETURN_STRING_LITERAL(QUIC_INVALID_VERSION);
RETURN_STRING_LITERAL(QUIC_INVALID_HEADER_ID);
RETURN_STRING_LITERAL(QUIC_INVALID_NEGOTIATED_VALUE);
RETURN_STRING_LITERAL(QUIC_DECOMPRESSION_FAILURE);
RETURN_STRING_LITERAL(QUIC_NETWORK_IDLE_TIMEOUT);
RETURN_STRING_LITERAL(QUIC_HANDSHAKE_TIMEOUT);
RETURN_STRING_LITERAL(QUIC_ERROR_MIGRATING_ADDRESS);
RETURN_STRING_LITERAL(QUIC_ERROR_MIGRATING_PORT);
RETURN_STRING_LITERAL(QUIC_PACKET_WRITE_ERROR);
RETURN_STRING_LITERAL(QUIC_PACKET_READ_ERROR);
RETURN_STRING_LITERAL(QUIC_EMPTY_STREAM_FRAME_NO_FIN);
RETURN_STRING_LITERAL(QUIC_INVALID_HEADERS_STREAM_DATA);
RETURN_STRING_LITERAL(QUIC_FLOW_CONTROL_RECEIVED_TOO_MUCH_DATA);
RETURN_STRING_LITERAL(QUIC_FLOW_CONTROL_SENT_TOO_MUCH_DATA);
RETURN_STRING_LITERAL(QUIC_FLOW_CONTROL_INVALID_WINDOW);
RETURN_STRING_LITERAL(QUIC_CONNECTION_IP_POOLED);
RETURN_STRING_LITERAL(QUIC_PROOF_INVALID);
RETURN_STRING_LITERAL(QUIC_CRYPTO_DUPLICATE_TAG);
RETURN_STRING_LITERAL(QUIC_CRYPTO_ENCRYPTION_LEVEL_INCORRECT);
RETURN_STRING_LITERAL(QUIC_CRYPTO_SERVER_CONFIG_EXPIRED);
RETURN_STRING_LITERAL(QUIC_INVALID_CHANNEL_ID_SIGNATURE);
RETURN_STRING_LITERAL(QUIC_CRYPTO_SYMMETRIC_KEY_SETUP_FAILED);
RETURN_STRING_LITERAL(QUIC_CRYPTO_MESSAGE_WHILE_VALIDATING_CLIENT_HELLO);
RETURN_STRING_LITERAL(QUIC_CRYPTO_UPDATE_BEFORE_HANDSHAKE_COMPLETE);
RETURN_STRING_LITERAL(QUIC_VERSION_NEGOTIATION_MISMATCH);
RETURN_STRING_LITERAL(QUIC_TOO_MANY_OUTSTANDING_SENT_PACKETS);
RETURN_STRING_LITERAL(QUIC_TOO_MANY_OUTSTANDING_RECEIVED_PACKETS);
RETURN_STRING_LITERAL(QUIC_CONNECTION_CANCELLED);
RETURN_STRING_LITERAL(QUIC_BAD_PACKET_LOSS_RATE);
RETURN_STRING_LITERAL(QUIC_PUBLIC_RESETS_POST_HANDSHAKE);
RETURN_STRING_LITERAL(QUIC_TIMEOUTS_WITH_OPEN_STREAMS);
RETURN_STRING_LITERAL(QUIC_FAILED_TO_SERIALIZE_PACKET);
RETURN_STRING_LITERAL(QUIC_TOO_MANY_AVAILABLE_STREAMS);
RETURN_STRING_LITERAL(QUIC_UNENCRYPTED_FEC_DATA);
RETURN_STRING_LITERAL(QUIC_BAD_MULTIPATH_FLAG);
RETURN_STRING_LITERAL(QUIC_IP_ADDRESS_CHANGED);
RETURN_STRING_LITERAL(QUIC_CONNECTION_MIGRATION_NO_MIGRATABLE_STREAMS);
RETURN_STRING_LITERAL(QUIC_CONNECTION_MIGRATION_TOO_MANY_CHANGES);
RETURN_STRING_LITERAL(QUIC_CONNECTION_MIGRATION_NO_NEW_NETWORK);
RETURN_STRING_LITERAL(QUIC_CONNECTION_MIGRATION_NON_MIGRATABLE_STREAM);
RETURN_STRING_LITERAL(QUIC_TOO_MANY_RTOS);
RETURN_STRING_LITERAL(QUIC_ATTEMPT_TO_SEND_UNENCRYPTED_STREAM_DATA);
RETURN_STRING_LITERAL(QUIC_MAYBE_CORRUPTED_MEMORY);
RETURN_STRING_LITERAL(QUIC_CRYPTO_CHLO_TOO_LARGE);
RETURN_STRING_LITERAL(QUIC_LAST_ERROR);
// Intentionally have no default case, so we'll break the build
// if we add errors and don't put them here.
}
// Return a default value so that we return this when |error| doesn't match
// any of the QuicErrorCodes. This can happen when the ConnectionClose
// frame sent by the peer (attacker) has invalid error code.
return "INVALID_ERROR_CODE";
}
// static
const char* QuicUtils::EncryptionLevelToString(EncryptionLevel level) {
switch (level) {
RETURN_STRING_LITERAL(ENCRYPTION_NONE);
RETURN_STRING_LITERAL(ENCRYPTION_INITIAL);
RETURN_STRING_LITERAL(ENCRYPTION_FORWARD_SECURE);
RETURN_STRING_LITERAL(NUM_ENCRYPTION_LEVELS);
}
return "INVALID_ENCRYPTION_LEVEL";
}
// static
const char* QuicUtils::TransmissionTypeToString(TransmissionType type) {
switch (type) {
RETURN_STRING_LITERAL(NOT_RETRANSMISSION);
RETURN_STRING_LITERAL(HANDSHAKE_RETRANSMISSION);
RETURN_STRING_LITERAL(LOSS_RETRANSMISSION);
RETURN_STRING_LITERAL(ALL_UNACKED_RETRANSMISSION);
RETURN_STRING_LITERAL(ALL_INITIAL_RETRANSMISSION);
RETURN_STRING_LITERAL(RTO_RETRANSMISSION);
RETURN_STRING_LITERAL(TLP_RETRANSMISSION);
}
return "INVALID_TRANSMISSION_TYPE";
}
// static
string QuicUtils::TagToString(QuicTag tag) {
char chars[sizeof tag];
bool ascii = true;
const QuicTag orig_tag = tag;
for (size_t i = 0; i < arraysize(chars); i++) {
chars[i] = static_cast<char>(tag);
if ((chars[i] == 0 || chars[i] == '\xff') && i == arraysize(chars) - 1) {
chars[i] = ' ';
}
if (!isprint(static_cast<unsigned char>(chars[i]))) {
ascii = false;
break;
}
tag >>= 8;
}
if (ascii) {
return string(chars, sizeof(chars));
}
return base::UintToString(orig_tag);
}
// static
QuicTagVector QuicUtils::ParseQuicConnectionOptions(
const std::string& connection_options) {
QuicTagVector options;
// Tokens are expected to be no more than 4 characters long, but we
// handle overflow gracefully.
for (const base::StringPiece& token :
base::SplitStringPiece(connection_options, ",", base::TRIM_WHITESPACE,
base::SPLIT_WANT_ALL)) {
uint32_t option = 0;
for (char token_char : base::Reversed(token)) {
option <<= 8;
option |= static_cast<unsigned char>(token_char);
}
options.push_back(option);
}
return options;
}
// static
string QuicUtils::StringToHexASCIIDump(StringPiece in_buffer) {
int offset = 0;
const int kBytesPerLine = 16; // Max bytes dumped per line
const char* buf = in_buffer.data();
int bytes_remaining = in_buffer.size();
string s; // our output
const char* p = buf;
while (bytes_remaining > 0) {
const int line_bytes = std::min(bytes_remaining, kBytesPerLine);
base::StringAppendF(&s, "0x%04x: ", offset); // Do the line header
for (int i = 0; i < kBytesPerLine; ++i) {
if (i < line_bytes) {
base::StringAppendF(&s, "%02x", static_cast<unsigned char>(p[i]));
} else {
s += " "; // two-space filler instead of two-space hex digits
}
if (i % 2)
s += ' ';
}
s += ' ';
for (int i = 0; i < line_bytes; ++i) { // Do the ASCII dump
s += (p[i] > 32 && p[i] < 127) ? p[i] : '.';
}
bytes_remaining -= line_bytes;
offset += line_bytes;
p += line_bytes;
s += '\n';
}
return s;
}
// static
void QuicUtils::DeleteFrames(QuicFrames* frames) {
for (QuicFrame& frame : *frames) {
switch (frame.type) {
// Frames smaller than a pointer are inlined, so don't need to be deleted.
case PADDING_FRAME:
case MTU_DISCOVERY_FRAME:
case PING_FRAME:
break;
case STREAM_FRAME:
delete frame.stream_frame;
break;
case ACK_FRAME:
delete frame.ack_frame;
break;
case STOP_WAITING_FRAME:
delete frame.stop_waiting_frame;
break;
case RST_STREAM_FRAME:
delete frame.rst_stream_frame;
break;
case CONNECTION_CLOSE_FRAME:
delete frame.connection_close_frame;
break;
case GOAWAY_FRAME:
delete frame.goaway_frame;
break;
case BLOCKED_FRAME:
delete frame.blocked_frame;
break;
case WINDOW_UPDATE_FRAME:
delete frame.window_update_frame;
break;
case PATH_CLOSE_FRAME:
delete frame.path_close_frame;
break;
case NUM_FRAME_TYPES:
DCHECK(false) << "Cannot delete type: " << frame.type;
}
}
frames->clear();
}
// static
void QuicUtils::RemoveFramesForStream(QuicFrames* frames,
QuicStreamId stream_id) {
QuicFrames::iterator it = frames->begin();
while (it != frames->end()) {
if (it->type != STREAM_FRAME || it->stream_frame->stream_id != stream_id) {
++it;
continue;
}
delete it->stream_frame;
it = frames->erase(it);
}
}
// static
void QuicUtils::ClearSerializedPacket(SerializedPacket* serialized_packet) {
if (!serialized_packet->retransmittable_frames.empty()) {
DeleteFrames(&serialized_packet->retransmittable_frames);
}
serialized_packet->encrypted_buffer = nullptr;
serialized_packet->encrypted_length = 0;
}
// static
uint64_t QuicUtils::PackPathIdAndPacketNumber(QuicPathId path_id,
QuicPacketNumber packet_number) {
// Setting the nonce below relies on QuicPathId and QuicPacketNumber being
// specific sizes.
static_assert(sizeof(path_id) == 1, "Size of QuicPathId changed.");
static_assert(sizeof(packet_number) == 8,
"Size of QuicPacketNumber changed.");
// Use path_id and lower 7 bytes of packet_number as lower 8 bytes of nonce.
uint64_t path_id_packet_number =
(static_cast<uint64_t>(path_id) << 56) | packet_number;
DCHECK(path_id != kDefaultPathId || path_id_packet_number == packet_number);
return path_id_packet_number;
}
// static
char* QuicUtils::CopyBuffer(const SerializedPacket& packet) {
char* dst_buffer = new char[packet.encrypted_length];
memcpy(dst_buffer, packet.encrypted_buffer, packet.encrypted_length);
return dst_buffer;
}
// static
PeerAddressChangeType QuicUtils::DetermineAddressChangeType(
const IPEndPoint& old_address,
const IPEndPoint& new_address) {
if (!IsInitializedIPEndPoint(old_address) ||
!IsInitializedIPEndPoint(new_address) || old_address == new_address) {
return NO_CHANGE;
}
if (old_address.address() == new_address.address()) {
return PORT_CHANGE;
}
bool old_ip_is_ipv4 = old_address.address().IsIPv4();
bool migrating_ip_is_ipv4 = new_address.address().IsIPv4();
if (old_ip_is_ipv4 && !migrating_ip_is_ipv4) {
return IPV4_TO_IPV6_CHANGE;
}
if (!old_ip_is_ipv4) {
return migrating_ip_is_ipv4 ? IPV6_TO_IPV4_CHANGE : IPV6_TO_IPV6_CHANGE;
}
if (IPAddressMatchesPrefix(old_address.address(), new_address.address(),
24)) {
// Subnet part does not change (here, we use /24), which is considered to be
// caused by NATs.
return IPV4_SUBNET_CHANGE;
}
return UNSPECIFIED_CHANGE;
}
string QuicUtils::HexEncode(const char* data, size_t length) {
return HexEncode(StringPiece(data, length));
}
string QuicUtils::HexEncode(StringPiece data) {
return ::base::HexEncode(data.data(), data.size());
}
string QuicUtils::HexDecode(const char* data, size_t length) {
return HexDecode(StringPiece(data, length));
}
string QuicUtils::HexDecode(StringPiece data) {
if (data.empty())
return "";
std::vector<uint8_t> v;
if (!base::HexStringToBytes(data.as_string(), &v))
return "";
string out;
if (!v.empty())
out.assign(reinterpret_cast<const char*>(&v[0]), v.size());
return out;
}
string QuicUtils::BinaryToAscii(StringPiece binary) {
string out = "";
for (const unsigned char c : binary) {
// Leading space.
out += " ";
if (isprint(c)) {
out += c;
} else {
out += '.';
}
}
return out;
}
} // namespace net