;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; ;;
;; Copyright (C) KolibriOS team 2004-2009. All rights reserved. ;;
;; Distributed under terms of the GNU General Public License ;;
;; ;;
;; TCP.INC ;;
;; ;;
;; Part of the tcp/ip network stack for KolibriOS ;;
;; ;;
;; Written by hidnplayr@kolibrios.org ;;
;; ;;
;; GNU GENERAL PUBLIC LICENSE ;;
;; Version 2, June 1991 ;;
;; ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
$Revision: 1257 $
TCP_RETRIES equ 5 ; Number of times to resend a Packet
TCP_PACKET_TTL equ 50 ; resend if not replied to in 1/100 s
TCP_SOCKET_TTL equ 10 ; # of secs to wait before closing socket
TCP_QUEUE_SIZE equ 16
struct TCP_Packet
.SourcePort dw ?
.DestinationPort dw ?
.SequenceNumber dd ?
.AckNumber dd ?
.DataOffset db ? ; DataOffset[0-3 bits] and Reserved[4-7]
.Flags db ? ; Reserved[0-1 bits]|URG|ACK|PSH|RST|SYN|FIN
.Window dw ?
.Checksum dw ?
.UrgentPointer dw ?
.Options rb 3
.Padding db ?
.Data:
ends
align 4
uglobal
TCP_PACKETS_TX rd MAX_IP
TCP_PACKETS_RX rd MAX_IP
TCP_IN_QUEUE rd (tcp_in_queue_entry.size*TCP_QUEUE_SIZE+queue.data)/4
TCP_OUT_QUEUE dd ?
rd (tcp_out_queue_entry.size*TCP_QUEUE_SIZE)/4
endg
align 4
iglobal
stateHandler:
dd stateTCB_LISTEN
dd stateTCB_SYN_SENT
dd stateTCB_SYN_RECEIVED
dd stateTCB_ESTABLISHED
dd stateTCB_FIN_WAIT_1
dd stateTCB_FIN_WAIT_2
dd stateTCB_CLOSE_WAIT
dd stateTCB_CLOSING
dd stateTCB_LAST_ACK
dd stateTCB_TIME_WAIT
dd stateTCB_CLOSED
endg
;-----------------------------------------------------------------
;
; TCP_init
;
; This function resets all TCP variables
;
; IN: /
; OUT: /
;
;-----------------------------------------------------------------
align 4
TCP_init:
xor eax, eax
mov edi, TCP_PACKETS_TX
mov ecx, 2*MAX_IP
rep stosd
init_queue TCP_IN_QUEUE
; tcp_out_queue is a special type of queue:
; The first dword is a counter of total packets queued.
; The remaining bytes are socket 'slots' wich use tcp_out_queue_entry data structure.
; An empty slot is know by the fact that tcp_out_queue_entry.data_ptr (first dword of the slot) is set to 0
; There are TCP_OUT_QUEUE_SIZE number of slots
xor eax, eax
mov esi, TCP_OUT_QUEUE
mov ecx, TCP_QUEUE_SIZE*tcp_out_queue_entry/4+1
rep stosd
ret
;-----------------------------------------------------------------
;
; TCP_decrease_socket_ttls
;
; IN: /
; OUT: /
;
;-----------------------------------------------------------------
align 4
TCP_decrease_socket_ttls:
; scan through all the sockets, decrementing active timers
mov ebx, net_sockets
cmp [ebx + SOCKET_head.NextPtr], 0
je .exit
.next_socket:
mov ebx, [ebx + SOCKET_head.NextPtr]
or ebx, ebx
jz .exit
cmp [ebx + SOCKET_head.Type], IP_PROTO_TCP
jne .next_socket
; DEBUGF 1, "K : %x-%x: %x-%x-%x-%u\n", [ebx + SOCKET.PID]:2, [ebx + SOCKET.Number]:2, [ebx + SOCKET.LocalPort]:4, [ebx + SOCKET.RemoteIP], [ebx + SOCKET.RemotePort]:4, [ebx + SOCKET.state]
cmp [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.timer], 0
jne .decrement_tcb
cmp [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.wndsizeTimer], 0
jne .decrement_wnd
jmp .next_socket
.decrement_tcb:
; decrement it, delete socket if TCB timer = 0 & socket in timewait state
dec [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.timer]
jnz .next_socket
cmp [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.state], TCB_TIMED_WAIT
jne .next_socket
push [ebx + SOCKET_head.PrevPtr]
stdcall net_socket_free, ebx
pop ebx
jmp .next_socket
.decrement_wnd:
; TODO - prove it works!
dec [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.wndsizeTimer]
jmp .next_socket
.exit:
ret
;-----------------------------------------------------------------
;
; TCP_send_queued:
;
; Decreases 'ttl' of tcp packets queued.
; if 'ttl' reaches 0, resend the packet and decrease 'retries'
; if 'retries' reaches zero, remove the queued packet
;
; IN: /
; OUT: /
;
;-----------------------------------------------------------------
align 4
TCP_send_queued:
cmp [TCP_OUT_QUEUE], 0
je .exit
mov eax, TCP_QUEUE_SIZE
mov ecx, [TCP_OUT_QUEUE]
mov esi, TCP_OUT_QUEUE+4
.loop:
cmp [esi + tcp_out_queue_entry.data_ptr], 0
jnz .found_one
add esi, tcp_out_queue_entry.size
loop .loop
.exit:
ret
.found_one:
dec [esi + tcp_out_queue_entry.ttl]
jz .send_it
.find_next:
add esi, tcp_out_queue_entry.size
dec eax
jz .exit
test ecx, ecx
jnz .loop
ret
.send_it:
push eax ecx esi
mov ebx, [esi + tcp_out_queue_entry.owner]
push [esi + tcp_out_queue_entry.data_size]
push [esi + tcp_out_queue_entry.data_ptr]
DEBUGF 1,"Now sending TCP packet %x, size: %u, owner: %x, sendproc %x\n", [esp], [esp+4], ebx, [esi + tcp_out_queue_entry.sendproc]
inc [TCP_PACKETS_TX]
call [esi + tcp_out_queue_entry.sendproc]
add esp, 8
pop esi ecx eax
dec [esi + tcp_out_queue_entry.retries]
jz .remove_it
mov [esi + tcp_out_queue_entry.ttl], TCP_PACKET_TTL
jmp .find_next
.remove_it:
push [esi + tcp_out_queue_entry.data_ptr]
mov [esi + tcp_out_queue_entry.data_ptr], 0
call kernel_free
jmp .find_next
;-----------------------------------------------------------------
;
; TCP_add_to_queue:
;
; Queue a TCP packet for sending
;
; IN: [esp] pointer to buffer
; [esp + 4] size of buffer
; ebx = driver struct
; esi = sender proc
; edx = acknum
; OUT: /
;
;-----------------------------------------------------------------
align 4
TCP_add_to_queue:
DEBUGF 1,"Adding packet to TCP queue, buffer: %x, size: %u, driver: %x, acknum: %x\n", [esp], [esp+4], ebx, edx
cmp [TCP_OUT_QUEUE], TCP_QUEUE_SIZE
jge .full
mov ecx, TCP_QUEUE_SIZE
mov eax, TCP_OUT_QUEUE+4
.loop:
cmp [eax + tcp_out_queue_entry.data_ptr], 0
je .found_it
add eax, tcp_out_queue_entry.size
loop .loop
.full: ; silently discard the packet
DEBUGF 1,"TCP queue is full!\n"
call kernel_free
add esp, 4
ret
.found_it: ; eax point to empty queue entry
pop [eax + tcp_out_queue_entry.data_ptr]
pop [eax + tcp_out_queue_entry.data_size]
mov [eax + tcp_out_queue_entry.ttl], 1 ; send immediately
mov [eax + tcp_out_queue_entry.retries], TCP_RETRIES
mov [eax + tcp_out_queue_entry.owner], ebx
mov [eax + tcp_out_queue_entry.sendproc], esi
mov [eax + tcp_out_queue_entry.seq_num], edx
inc [TCP_OUT_QUEUE]
sub eax, TCP_OUT_QUEUE+4
DEBUGF 1,"Added to queue in pos %u\n", eax
ret
;-----------------------------------------------------------------
;
; TCP_handler:
;
; Called by IPv4_handler,
; this procedure will inject the tcp data diagrams in the application sockets.
;
; IN: Pointer to buffer in [esp]
; size of buffer in [esp+4]
; pointer to device struct in ebx
; TCP Packet size in ecx
; pointer to TCP Packet data in edx
; SourceAddres in esi
; OUT: /
;
;-----------------------------------------------------------------
align 4
TCP_handler :
DEBUGF 1,"TCP_Handler\n"
; TODO: validate checksum
; IP Packet TCP Destination Port = local Port
; IP Packet SA = Remote IP OR = 0
; IP Packet TCP Source Port = remote Port OR = 0
mov ebx, net_sockets
.socket_loop:
mov ebx, [ebx + SOCKET_head.NextPtr]
or ebx, ebx
jz .dump
mov ax, [edx + TCP_Packet.DestinationPort]
cmp [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.LocalPort], ax
jne .socket_loop
mov eax, [ebx + SOCKET_head.end + IPv4_SOCKET.RemoteIP]
cmp eax, esi
je @f
test eax, eax
jne .socket_loop
@@:
mov ax, [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.RemotePort]
cmp [edx + TCP_Packet.SourcePort] , ax
je .change_state
test ax, ax
jnz .socket_loop
.change_state:
DEBUGF 1,"Found valid socket for packet\n"
inc [TCP_PACKETS_RX]
push ebx
lea ebx, [ebx + SOCKET_head.lock]
call wait_mutex
pop ebx
;----------------------------------
; ebx is pointer to socket
; ecx is size of tcp packet
; edx is pointer to tcp packet
; as a Packet has been received, update the TCB timer
mov [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.timer], TCP_SOCKET_TTL
; If the received Packet has an ACK bit set, remove any Packets in the resend queue that this received Packet acknowledges
test [edx + TCP_Packet.Flags], TH_ACK
jz .call_handler ; No ACK, so no data yet
; mov eax, [edx + TCP_Packet.SequenceNumber] ; Calculate sequencenumber in eax
; bswap eax ;
; add eax, ecx ;
mov eax, [edx + TCP_Packet.AckNumber]
mov [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.last_ack_number], eax
;---------
cmp [TCP_OUT_QUEUE], 0
je .call_handler
push ecx
DEBUGF 1,"Removing all queued packets with smaller ACK\n"
mov ecx, TCP_QUEUE_SIZE
mov esi, TCP_OUT_QUEUE+4
.loop:
cmp [esi + tcp_out_queue_entry.data_ptr], 0
je .maybe_next
cmp [esi + tcp_out_queue_entry.seq_num], eax
jg .maybe_next
; TODO: check if the packets belong to the same tcp connection !
DEBUGF 1,"Removing a queued packet\n"
push [esi + tcp_out_queue_entry.data_ptr]
mov [esi + tcp_out_queue_entry.data_ptr], 0
dec [TCP_OUT_QUEUE]
call kernel_free
.maybe_next:
add esi, tcp_out_queue_entry.size
loop .loop
pop ecx
.call_handler:
; Call handler for given TCB state
mov eax, [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.state]
DEBUGF 1,"Socket state: %u\n", eax
cmp eax, TCB_LISTEN
jb .dump
cmp eax, TCB_CLOSED
ja .dump
dec eax
shl eax, 2
add eax, stateHandler
call dword[eax]
.dump:
DEBUGF 1,"Dumping TCP packet\n"
call kernel_free
add esp, 4 ; pop (balance stack)
ret
;-----------------------------------------------------------------
;
; TCP_socket_send
;
; IN: eax = socket pointer
; ecx = number of bytes to send
; esi = pointer to data
;
;-----------------------------------------------------------------
align 4
TCP_socket_send:
DEBUGF 1,"Creating TCP Packet\n"
mov di , IP_PROTO_TCP
; Create an IPv4 Packet of the correct size
push eax
mov ebx, [eax + SOCKET_head.end + IPv4_SOCKET.LocalIP]
mov eax, [eax + SOCKET_head.end + IPv4_SOCKET.RemoteIP]
; meanwhile, create the pseudoheader in stack,
; (now that we still have all the variables that are needed.)
push cx
push di
push eax
push ebx
push ecx esi eax ; save some variables for later
add ecx, TCP_Packet.Options
call IPv4_create_packet
cmp edi, -1
je .fail
pop esi
; Now add the TCP header to the IPv4 packet
push [esi + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.SND_NXT]
pop [edi + TCP_Packet.SequenceNumber]
push dword [esi + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.LocalPort]
pop dword [edi + TCP_Packet.SourcePort]
push [esi + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.SND_NXT]
pop [edi + TCP_Packet.AckNumber]
mov al, [eax + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.flags]
mov [edi + TCP_Packet.Flags], al
mov [edi + TCP_Packet.Window], 0x0005 ; 1280 bytes
mov [edi + TCP_Packet.UrgentPointer], 0
mov [edi + TCP_Packet.DataOffset], 0x50
mov [edi + TCP_Packet.Checksum], 0
; Copy the data
mov esi, [esp]
mov ecx, [esp+4]
add edi, TCP_Packet.Options
shr ecx, 1
jnc .nb
movsb
.nb: shr ecx, 1
jnc .nw
movsw
.nw: rep movsd
; Now, calculate the checksum for pseudoheader
xor edx, edx
mov ecx, 12
mov esi, esp
call checksum_1
add esp, 12 ; remove the pseudoheader from stack
; And that of the data
pop esi
pop ecx
call checksum_1
; Now create the final checksum and store it in TCP header
call checksum_2
mov [edi + TCP_Packet.Checksum], dx
; And now, send it!
DEBUGF 1,"Sending TCP Packet to device %x\n", ebx
lea esi, [ebx+ETH_DEVICE.transmit]
mov edx, [edi + TCP_Packet.AckNumber]
jmp TCP_add_to_queue
.fail:
add esp, 12+12+4
ret
;-----------------------------------------------------------------
;
; TCP_send_ack
;
; IN: eax = socket pointer
; bl = flags
;
;-----------------------------------------------------------------
align 4
TCP_send_ack:
DEBUGF 1,"Creating TCP ACK, socket: %x, flags: %x\n",eax, bl
mov di , IP_PROTO_TCP
mov ecx, TCP_Packet.Options
push bx eax
; Create an IPv4 Packet of the correct size
mov ebx, [eax + SOCKET_head.end + IPv4_SOCKET.LocalIP]
mov eax, [eax + SOCKET_head.end + IPv4_SOCKET.RemoteIP]
call IPv4_create_packet
cmp edi, -1
je .fail
; Fill in the TCP header
pop esi
push [esi + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.SND_NXT]
pop [edi + TCP_Packet.SequenceNumber]
push dword [esi + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.LocalPort] ; both ports at once
pop dword [edi + TCP_Packet.SourcePort]
push [esi + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.RCV_NXT]
pop [edi + TCP_Packet.AckNumber]
pop cx
mov [edi + TCP_Packet.Flags], cl
mov [edi + TCP_Packet.Window], 0x0005 ; 1280 bytes
mov [edi + TCP_Packet.UrgentPointer], 0
mov [edi + TCP_Packet.DataOffset], 0x50
mov [edi + TCP_Packet.Checksum], 0
push edx eax
; lea esi, [esi + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.SND_NXT]
; inc_INET esi
; Now, calculate the checksum
pushw TCP_Packet.Options shl 8
pushw IP_PROTO_TCP shl 8
pushd [edi-4] ; destination address ; TODO: fix this, IPv4 packet could have options..
pushd [edi-8] ; source address
xor edx, edx
mov ecx, TCP_Packet.Options
mov esi, edi
call checksum_1
mov ecx, 12
mov esi, esp
call checksum_1
add esp, 12 ; remove the pseudoheader from stack
; and store it in TCP header
call checksum_2
mov [edi + TCP_Packet.Checksum], dx
; And now, send the packet!
DEBUGF 1,"Sending TCP Packet to device %x\n", ebx
mov esi, [ebx + ETH_DEVICE.transmit]
mov edx, [edi + TCP_Packet.SequenceNumber]
jmp TCP_add_to_queue
.fail:
add esp, 2+4
ret
;---------- TCB state handlers start here
align 4
stateTCB_LISTEN:
DEBUGF 1,"TCBStateHandler: Listen\n"
; In this case, we are expecting a SYN Packet
; For now, if the Packet is a SYN, process it, and send a response
; If not, ignore it
; Look at control flags
test [edx + TCP_Packet.Flags], TH_SYN
jz .exit
; Exit if backlog queue is full
mov ax, [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.backlog_cur]
cmp ax, [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.backlog]
jae .exit
; Allocate new socket
push esi
call net_socket_alloc
pop esi
test eax, eax
jz .exit
; Copy structure from current socket to new, including lock
push esi edi
lea esi, [ebx + SOCKET_head.PID] ; yes, PID must also be copied
lea edi, [eax + SOCKET_head.PID]
mov ecx, ((SOCKET_head.end - SOCKET_head.PID) + IPv4_SOCKET.end + TCP_SOCKET.end + 3)/4
rep movsd
pop edi esi
; Push pointer to new socket to queue
movzx ecx, [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.backlog_cur]
inc [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.backlog_cur]
mov [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.end + ecx*4], eax
; We have a SYN. update the socket with this IP Packets details,
; And send a response
mov [eax + SOCKET_head.end + IPv4_SOCKET.RemoteIP], esi ; IP source address
mov cx, [edx + TCP_Packet.SourcePort]
mov [eax + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.RemotePort], cx
mov ecx, [edx + TCP_Packet.SequenceNumber]
mov [eax + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.IRS], ecx
mov [eax + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.RCV_NXT], ecx
lea esi, [eax + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.RCV_NXT]
inc_INET esi ; RCV.NXT
mov ecx, [eax + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.ISS]
mov [eax + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.SND_NXT], ecx
mov [eax + SOCKET_head.lock], 0
mov [ebx + SOCKET_head.lock], 0
push eax
; Now construct the response
mov bl, TH_SYN + TH_ACK
call TCP_send_ack
pop eax
mov [eax + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.state], TCB_SYN_RECEIVED
call notify_network_event
; increment SND.NXT in socket
lea esi, [eax + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.SND_NXT]
inc_INET esi
ret
.exit:
mov [ebx + SOCKET_head.lock], 0
ret
align 4
stateTCB_SYN_SENT:
DEBUGF 1,"TCBStateHandler: Syn_Sent\n"
; We are awaiting an ACK to our SYN, with a SYM
; Look at control flags - expecting an ACK
mov al, [edx + TCP_Packet.Flags]
and al, TH_SYN + TH_ACK
cmp al, TH_SYN + TH_ACK
je .syn_ack
test al, TH_SYN
jz .exit
mov [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.state], TCB_SYN_RECEIVED
pushd TH_SYN + TH_ACK
jmp .send
.syn_ack:
mov [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.state], TCB_ESTABLISHED
pushd TH_ACK
.send:
; Store the recv.nxt field
mov eax, [edx + TCP_Packet.SequenceNumber]
mov [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.IRS], eax
bswap eax
inc eax
bswap eax
mov [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.RCV_NXT], eax ; Update our recv.nxt field
mov [ebx + SOCKET_head.lock], 0
lea esi, [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.SND_NXT]
inc_INET esi
; Send an ACK
mov eax, ebx
pop ebx
call TCP_send_ack
.exit:
mov [ebx + SOCKET_head.lock], 0
ret
align 4
stateTCB_SYN_RECEIVED:
DEBUGF 1,"TCBStateHandler: Syn_received\n"
; In this case, we are expecting an ACK Packet
; For now, if the Packet is an ACK, process it,
; If not, ignore it
test [edx + TCP_Packet.Flags], TH_RST
jz .check_ack
; push [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.OrigRemotePort]
; pop [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.RemotePort]
; push [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.OrigRemoteIP]
; pop [ebx + SOCKET_head.end + IPv4_SOCKET.RemoteIP]
mov [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.state], TCB_LISTEN
jmp .exit
.check_ack:
; Look at control flags - expecting an ACK
test [edx + TCP_Packet.Flags], TH_ACK
jz .exit
mov [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.state], TCB_ESTABLISHED
mov eax, ebx
call notify_network_event
.exit:
mov [ebx + SOCKET_head.lock], 0
ret
align 4
stateTCB_ESTABLISHED:
DEBUGF 1,"TCBStateHandler: Established\n"
mov eax, [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.RCV_NXT]
cmp eax, [edx + TCP_Packet.SequenceNumber]
jne .exit
; Here we are expecting data, or a request to close
; OR both...
; Did we receive a FIN or RST?
test [edx + TCP_Packet.Flags], TH_FIN
jz .check_ack
; It was a fin or reset.
;;; TODO: write following code:
; Remove resend entries from the queue - I dont want to send any more data
; Send an ACK to that fin, and enter closewait state
.check_ack:
; Check that we received an ACK
test [edx + TCP_Packet.Flags], TH_ACK
jz .exit
DEBUGF 1,"Received ACK\n"
; First, look at the incoming window. If this is less than or equal to 1024,
; Set the socket window timer to 1. This will stop an additional Packets being queued.
; ** I may need to tweak this value, since I do not know how many Packets are already queued
push ecx
mov cx, [edx + TCP_Packet.Window]
xchg cl, ch
cmp cx, 1024
ja @f
mov [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.wndsizeTimer], 1
@@:
pop ecx
test ecx, ecx
jnz .data ; Read data, if any
lea esi, [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.SND_NXT]
inc_INET esi
; If we had received a fin, we need to ACK it.
cmp [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.state], TCB_CLOSE_WAIT
je .ack
jmp .exit
.data:
;;;
lea esi, [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.SND_NXT]
add_INET esi
DEBUGF 1,"Got data!\n"
mov esi, [esp + 4]
sub edx, esi
mov edi, edx
mov eax, ebx
call socket_internal_receiver
.ack:
mov [ebx + SOCKET_head.lock], 0
; Send an ACK
mov eax, ebx
mov bl, TH_ACK
call TCP_send_ack
.exit:
mov [ebx + SOCKET_head.lock], 0
ret
align 4
stateTCB_FIN_WAIT_1:
DEBUGF 1,"TCBStateHandler: Fin_wait_1\n"
; We can either receive an ACK of a fin, or a fin
mov al, [edx + TCP_Packet.Flags]
and al, TH_FIN + TH_ACK
cmp al, TH_ACK
jne @f
; It was an ACK
mov [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.state], TCB_FIN_WAIT_2
jmp .exit
@@: mov [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.state], TCB_CLOSING
cmp al, TH_FIN
je @f
mov [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.state], TCB_TIMED_WAIT
@@: lea esi, [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.RCV_NXT]
inc_INET esi
mov [ebx + SOCKET_head.lock], 0
; Send an ACK
mov eax, ebx
mov bl, TH_ACK
call TCP_send_ack
.exit:
mov [ebx + SOCKET_head.lock], 0
ret
align 4
stateTCB_FIN_WAIT_2:
DEBUGF 1,"TCBStateHandler: Fin_wait_2\n"
test [edx + TCP_Packet.Flags], TH_FIN
jz .exit
; Change state, as we have a fin
mov [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.state], TCB_TIMED_WAIT
lea esi, [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.RCV_NXT]
inc_INET esi
mov [ebx + SOCKET_head.lock], 0
; Send an ACK
mov eax, ebx
mov bl, TH_ACK
call TCP_send_ack
.exit:
mov [ebx + SOCKET_head.lock], 0
ret
align 4
stateTCB_CLOSE_WAIT:
DEBUGF 1,"TCBStateHandler: close_wait\n"
; Intentionally left empty
; socket_close_tcp handles this
mov [ebx + SOCKET_head.lock], 0
ret
align 4
stateTCB_CLOSING:
DEBUGF 1,"TCBStateHandler: closingn\n"
; We can either receive an ACK of a fin, or a fin
test [edx + TCP_Packet.Flags], TH_ACK
jz .exit
mov [ebx + SOCKET_head.end + IPv4_SOCKET.end + TCP_SOCKET.state], TCB_TIMED_WAIT
.exit:
mov [ebx + SOCKET_head.lock], 0
ret
align 4
stateTCB_LAST_ACK:
DEBUGF 1,"TCBStateHandler: last_ackn\n"
; Look at control flags - expecting an ACK
test [edx + TCP_Packet.Flags], TH_ACK
jz .exit
mov [ebx + SOCKET_head.lock], 0
; delete the socket
stdcall net_socket_free, ebx
.exit:
ret
align 4
stateTCB_TIME_WAIT:
DEBUGF 1,"TCBStateHandler: time_wait\n"
mov [ebx + SOCKET_head.lock], 0
ret
align 4
stateTCB_CLOSED:
DEBUGF 1,"TCBStateHandler: closed\n"
mov [ebx + SOCKET_head.lock], 0
ret
;---------------------------------------------------------------------------
;
; TCP_API
;
; This function is called by system function 75
;
; IN: subfunction number in bl
; device number in bh
; ecx, edx, .. depends on subfunction
;
; OUT:
;
;---------------------------------------------------------------------------
align 4
TCP_API:
movzx eax, bh
shl eax, 2
test bl, bl
jz .packets_tx ; 0
dec bl
jz .packets_rx ; 1
.error:
mov eax, -1
ret
.packets_tx:
add eax, TCP_PACKETS_TX
mov eax, [eax]
ret
.packets_rx:
add eax, TCP_PACKETS_RX
mov eax, [eax]
ret