TCPSocket.cpp 6.8 KB

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  1. #include <Kernel/Devices/RandomDevice.h>
  2. #include <Kernel/Net/NetworkAdapter.h>
  3. #include <Kernel/Net/Routing.h>
  4. #include <Kernel/Net/TCP.h>
  5. #include <Kernel/Net/TCPSocket.h>
  6. #include <Kernel/Process.h>
  7. Lockable<HashMap<word, TCPSocket*>>& TCPSocket::sockets_by_port()
  8. {
  9. static Lockable<HashMap<word, TCPSocket*>>* s_map;
  10. if (!s_map)
  11. s_map = new Lockable<HashMap<word, TCPSocket*>>;
  12. return *s_map;
  13. }
  14. TCPSocketHandle TCPSocket::from_port(word port)
  15. {
  16. RefPtr<TCPSocket> socket;
  17. {
  18. LOCKER(sockets_by_port().lock());
  19. auto it = sockets_by_port().resource().find(port);
  20. if (it == sockets_by_port().resource().end())
  21. return {};
  22. socket = (*it).value;
  23. ASSERT(socket);
  24. }
  25. return { move(socket) };
  26. }
  27. TCPSocket::TCPSocket(int protocol)
  28. : IPv4Socket(SOCK_STREAM, protocol)
  29. {
  30. }
  31. TCPSocket::~TCPSocket()
  32. {
  33. LOCKER(sockets_by_port().lock());
  34. sockets_by_port().resource().remove(local_port());
  35. }
  36. NonnullRefPtr<TCPSocket> TCPSocket::create(int protocol)
  37. {
  38. return adopt(*new TCPSocket(protocol));
  39. }
  40. int TCPSocket::protocol_receive(const ByteBuffer& packet_buffer, void* buffer, size_t buffer_size, int flags)
  41. {
  42. (void)flags;
  43. ASSERT(!packet_buffer.is_null());
  44. auto& ipv4_packet = *(const IPv4Packet*)(packet_buffer.pointer());
  45. auto& tcp_packet = *static_cast<const TCPPacket*>(ipv4_packet.payload());
  46. size_t payload_size = packet_buffer.size() - sizeof(IPv4Packet) - tcp_packet.header_size();
  47. kprintf("payload_size %u, will it fit in %u?\n", payload_size, buffer_size);
  48. ASSERT(buffer_size >= payload_size);
  49. memcpy(buffer, tcp_packet.payload(), payload_size);
  50. return payload_size;
  51. }
  52. int TCPSocket::protocol_send(const void* data, int data_length)
  53. {
  54. auto* adapter = adapter_for_route_to(peer_address());
  55. if (!adapter)
  56. return -EHOSTUNREACH;
  57. send_tcp_packet(TCPFlags::PUSH | TCPFlags::ACK, data, data_length);
  58. return data_length;
  59. }
  60. void TCPSocket::send_tcp_packet(word flags, const void* payload, int payload_size)
  61. {
  62. // FIXME: Maybe the socket should be bound to an adapter instead of looking it up every time?
  63. auto* adapter = adapter_for_route_to(peer_address());
  64. ASSERT(adapter);
  65. auto buffer = ByteBuffer::create_zeroed(sizeof(TCPPacket) + payload_size);
  66. auto& tcp_packet = *(TCPPacket*)(buffer.pointer());
  67. ASSERT(local_port());
  68. tcp_packet.set_source_port(local_port());
  69. tcp_packet.set_destination_port(peer_port());
  70. tcp_packet.set_window_size(1024);
  71. tcp_packet.set_sequence_number(m_sequence_number);
  72. tcp_packet.set_data_offset(sizeof(TCPPacket) / sizeof(dword));
  73. tcp_packet.set_flags(flags);
  74. if (flags & TCPFlags::ACK)
  75. tcp_packet.set_ack_number(m_ack_number);
  76. if (flags == TCPFlags::SYN) {
  77. ++m_sequence_number;
  78. } else {
  79. m_sequence_number += payload_size;
  80. }
  81. memcpy(tcp_packet.payload(), payload, payload_size);
  82. tcp_packet.set_checksum(compute_tcp_checksum(adapter->ipv4_address(), peer_address(), tcp_packet, payload_size));
  83. kprintf("sending tcp packet from %s:%u to %s:%u with (%s %s) seq_no=%u, ack_no=%u\n",
  84. adapter->ipv4_address().to_string().characters(),
  85. local_port(),
  86. peer_address().to_string().characters(),
  87. peer_port(),
  88. tcp_packet.has_syn() ? "SYN" : "",
  89. tcp_packet.has_ack() ? "ACK" : "",
  90. tcp_packet.sequence_number(),
  91. tcp_packet.ack_number());
  92. adapter->send_ipv4(MACAddress(), peer_address(), IPv4Protocol::TCP, move(buffer));
  93. }
  94. NetworkOrdered<word> TCPSocket::compute_tcp_checksum(const IPv4Address& source, const IPv4Address& destination, const TCPPacket& packet, word payload_size)
  95. {
  96. struct [[gnu::packed]] PseudoHeader
  97. {
  98. IPv4Address source;
  99. IPv4Address destination;
  100. byte zero;
  101. byte protocol;
  102. NetworkOrdered<word> payload_size;
  103. };
  104. PseudoHeader pseudo_header { source, destination, 0, (byte)IPv4Protocol::TCP, sizeof(TCPPacket) + payload_size };
  105. dword checksum = 0;
  106. auto* w = (const NetworkOrdered<word>*)&pseudo_header;
  107. for (size_t i = 0; i < sizeof(pseudo_header) / sizeof(word); ++i) {
  108. checksum += w[i];
  109. if (checksum > 0xffff)
  110. checksum = (checksum >> 16) + (checksum & 0xffff);
  111. }
  112. w = (const NetworkOrdered<word>*)&packet;
  113. for (size_t i = 0; i < sizeof(packet) / sizeof(word); ++i) {
  114. checksum += w[i];
  115. if (checksum > 0xffff)
  116. checksum = (checksum >> 16) + (checksum & 0xffff);
  117. }
  118. ASSERT(packet.data_offset() * 4 == sizeof(TCPPacket));
  119. w = (const NetworkOrdered<word>*)packet.payload();
  120. for (size_t i = 0; i < payload_size / sizeof(word); ++i) {
  121. checksum += w[i];
  122. if (checksum > 0xffff)
  123. checksum = (checksum >> 16) + (checksum & 0xffff);
  124. }
  125. if (payload_size & 1) {
  126. word expanded_byte = ((const byte*)packet.payload())[payload_size - 1] << 8;
  127. checksum += expanded_byte;
  128. if (checksum > 0xffff)
  129. checksum = (checksum >> 16) + (checksum & 0xffff);
  130. }
  131. return ~(checksum & 0xffff);
  132. }
  133. KResult TCPSocket::protocol_connect(FileDescription& description, ShouldBlock should_block)
  134. {
  135. auto* adapter = adapter_for_route_to(peer_address());
  136. if (!adapter)
  137. return KResult(-EHOSTUNREACH);
  138. allocate_local_port_if_needed();
  139. m_sequence_number = 0;
  140. m_ack_number = 0;
  141. send_tcp_packet(TCPFlags::SYN);
  142. m_state = State::Connecting;
  143. if (should_block == ShouldBlock::Yes) {
  144. current->block(Thread::BlockedConnect, description);
  145. ASSERT(is_connected());
  146. return KSuccess;
  147. }
  148. return KResult(-EINPROGRESS);
  149. }
  150. int TCPSocket::protocol_allocate_local_port()
  151. {
  152. static const word first_ephemeral_port = 32768;
  153. static const word last_ephemeral_port = 60999;
  154. static const word ephemeral_port_range_size = last_ephemeral_port - first_ephemeral_port;
  155. word first_scan_port = first_ephemeral_port + RandomDevice::random_value() % ephemeral_port_range_size;
  156. LOCKER(sockets_by_port().lock());
  157. for (word port = first_scan_port;;) {
  158. auto it = sockets_by_port().resource().find(port);
  159. if (it == sockets_by_port().resource().end()) {
  160. set_local_port(port);
  161. sockets_by_port().resource().set(port, this);
  162. return port;
  163. }
  164. ++port;
  165. if (port > last_ephemeral_port)
  166. port = first_ephemeral_port;
  167. if (port == first_scan_port)
  168. break;
  169. }
  170. return -EADDRINUSE;
  171. }
  172. bool TCPSocket::protocol_is_disconnected() const
  173. {
  174. return m_state == State::Disconnecting || m_state == State::Disconnected;
  175. }
  176. KResult TCPSocket::protocol_bind()
  177. {
  178. LOCKER(sockets_by_port().lock());
  179. if (sockets_by_port().resource().contains(local_port()))
  180. return KResult(-EADDRINUSE);
  181. sockets_by_port().resource().set(local_port(), this);
  182. return KSuccess;
  183. }