blob: f3700c776c56b87a31e374d9aa0974107b300daf [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.
// Some socket related helper methods for quic.
#include <netinet/in.h>
#include <sys/socket.h>
#include <string>
#include "base/macros.h"
#include "net/base/ip_address.h"
#include "net/base/ip_endpoint.h"
#include "net/third_party/quic/core/quic_bandwidth.h"
#include "net/third_party/quic/core/quic_types.h"
#include "starboard/types.h"
#define MMSG_MORE 0
namespace quic {
class QuicIpAddress;
class QuicSocketAddress;
// This is the structure that SO_TIMESTAMPING fills into the cmsg header. It is
// well-defined, but does not have a definition in a public header. See
// for more
// information.
struct LinuxTimestamping {
// The converted system time of the timestamp.
struct timespec systime;
// Deprecated; serves only as padding.
struct timespec hwtimetrans;
// The raw hardware timestamp.
struct timespec hwtimeraw;
const int kCmsgSpaceForIpv4 = CMSG_SPACE(sizeof(in_pktinfo));
const int kCmsgSpaceForIpv6 = CMSG_SPACE(sizeof(in6_pktinfo));
// kCmsgSpaceForIp should be big enough to hold both IPv4 and IPv6 packet info.
const int kCmsgSpaceForIp = (kCmsgSpaceForIpv4 < kCmsgSpaceForIpv6)
? kCmsgSpaceForIpv6
: kCmsgSpaceForIpv4;
const int kCmsgSpaceForSegmentSize = CMSG_SPACE(sizeof(uint16_t));
const int kCmsgSpaceForRecvQueueOverflow = CMSG_SPACE(sizeof(int));
const int kCmsgSpaceForLinuxTimestamping =
const int kCmsgSpaceForTTL = CMSG_SPACE(sizeof(int));
// The minimum cmsg buffer size when receiving a packet. It is possible for a
// received packet to contain both IPv4 and IPv6 addresses.
const int kCmsgSpaceForReadPacket =
kCmsgSpaceForRecvQueueOverflow + kCmsgSpaceForIpv4 + kCmsgSpaceForIpv6 +
kCmsgSpaceForLinuxTimestamping + kCmsgSpaceForTTL;
// QuicMsgHdr is used to build msghdr objects that can be used send packets via
// ::sendmsg.
// Example:
// // cbuf holds control messages(cmsgs). The size is determined from what
// // cmsgs will be set for this msghdr.
// char cbuf[kCmsgSpaceForIp + kCmsgSpaceForSegmentSize];
// QuicMsgHdr hdr(packet_buf, packet_buf_len, peer_addr, cbuf, sizeof(cbuf));
// // Set IP in cmsgs.
// hdr.SetIpInNextCmsg(self_addr);
// // Set GSO size in cmsgs.
// *hdr.GetNextCmsgData<uint16_t>(SOL_UDP, UDP_SEGMENT) = 1200;
// QuicSocketUtils::WritePacket(fd, hdr);
class QuicMsgHdr {
QuicMsgHdr(const char* buffer,
size_t buf_len,
const QuicSocketAddress& peer_address,
char* cbuf,
size_t cbuf_size);
// Set IP info in the next cmsg. Both IPv4 and IPv6 are supported.
void SetIpInNextCmsg(const QuicIpAddress& self_address);
template <typename DataType>
DataType* GetNextCmsgData(int cmsg_level, int cmsg_type) {
return reinterpret_cast<DataType*>(
GetNextCmsgDataInternal(cmsg_level, cmsg_type, sizeof(DataType)));
const msghdr* hdr() const { return &hdr_; }
void* GetNextCmsgDataInternal(int cmsg_level,
int cmsg_type,
size_t data_size);
msghdr hdr_;
IOVEC iov_;
sockaddr_storage raw_peer_address_;
char* cbuf_;
const size_t cbuf_size_;
// The last cmsg populated so far. nullptr means nothing has been populated.
cmsghdr* cmsg_;
class QuicSocketUtils {
QuicSocketUtils() = delete;
// Fills in |address| if |hdr| contains IP_PKTINFO or IPV6_PKTINFO. Fills in
// |timestamp| if |hdr| contains |SO_TIMESTAMPING|. |address| and |timestamp|
// must not be null.
static void GetAddressAndTimestampFromMsghdr(struct msghdr* hdr,
QuicIpAddress* address,
QuicWallTime* walltimestamp);
// If the msghdr contains an SO_RXQ_OVFL entry, this will set dropped_packets
// to the correct value and return true. Otherwise it will return false.
static bool GetOverflowFromMsghdr(struct msghdr* hdr,
QuicPacketCount* dropped_packets);
// If the msghdr contains an IP_TTL entry, this will set ttl to the correct
// value and return true. Otherwise it will return false.
static bool GetTtlFromMsghdr(struct msghdr* hdr, int* ttl);
// Sets either IP_PKTINFO or IPV6_PKTINFO on the socket, based on
// address_family. Returns the return code from setsockopt.
static int SetGetAddressInfo(int fd, int address_family);
// Sets SO_TIMESTAMPING on the socket for software receive timestamping.
// Returns the return code from setsockopt.
static int SetGetSoftwareReceiveTimestamp(int fd);
// Sets the send buffer size to |size| and returns false if it fails.
static bool SetSendBufferSize(int fd, size_t size);
// Sets the receive buffer size to |size| and returns false if it fails.
static bool SetReceiveBufferSize(int fd, size_t size);
// Reads buf_len from the socket. If reading is successful, returns bytes
// read and sets peer_address to the peer address. Otherwise returns -1.
// If dropped_packets is non-null, it will be set to the number of packets
// dropped on the socket since the socket was created, assuming the kernel
// supports this feature.
// If self_address is non-null, it will be set to the address the peer sent
// packets to, assuming a packet was read.
// If timestamp is non-null, it will be filled with the timestamp of the
// received packet, assuming a packet was read and the platform supports
// packet receipt timestamping. If the platform does not support packet
// receipt timestamping, timestamp will not be changed.
static int ReadPacket(int fd,
char* buffer,
size_t buf_len,
QuicPacketCount* dropped_packets,
QuicIpAddress* self_address,
QuicWallTime* walltimestamp,
QuicSocketAddress* peer_address);
// Writes buf_len to the socket. If writing is successful, sets the result's
// status to WRITE_STATUS_OK and sets bytes_written. Otherwise sets the
// result's status to WRITE_STATUS_BLOCKED or WRITE_STATUS_ERROR and sets
// error_code to errno.
static WriteResult WritePacket(int fd,
const char* buffer,
size_t buf_len,
const QuicIpAddress& self_address,
const QuicSocketAddress& peer_address);
// Writes the packet in |hdr| to the socket, using ::sendmsg.
static WriteResult WritePacket(int fd, const QuicMsgHdr& hdr);
// Set IP(self_address) in |cmsg_data|. Does not touch other fields in the
// containing cmsghdr.
static void SetIpInfoInCmsgData(const QuicIpAddress& self_address,
void* cmsg_data);
// A helper for WritePacket which fills in the cmsg with the supplied self
// address.
// Returns the length of the packet info structure used.
static size_t SetIpInfoInCmsg(const QuicIpAddress& self_address,
cmsghdr* cmsg);
// Creates a UDP socket and sets appropriate socket options for QUIC.
// Returns the created FD if successful, -1 otherwise.
// |overflow_supported| is set to true if the socket supports it.
static int CreateUDPSocket(const QuicSocketAddress& address,
int32_t receive_buffer_size,
int32_t send_buffer_size,
bool* overflow_supported);
} // namespace quic