;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; ;;
;; Copyright (C) KolibriOS team 2004-2008. All rights reserved. ;;
;; Distributed under terms of the GNU General Public License ;;
;; ;;
;; SOCKET.INC ;;
;; ;;
;; Sockets constants, structures and functions ;;
;; ;;
;; This file contains the following: ;;
;; is_localport_unused ;;
;; get_free_socket ;;
;; socket_open ;;
;; socket_open_tcp ;;
;; socket_close ;;
;; socket_close_tcp ;;
;; socket_poll ;;
;; socket_status ;;
;; socket_read ;;
;; socket_write ;;
;; socket_write_tcp ;;
;; ;;
;; ;;
;; Changes history: ;;
;; 22.09.2003 - [Mike Hibbett] : mikeh@oceanfree.net ;;
;; 11.11.2006 - [Johnny_B] and [smb] ;;
;; ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
$Revision: 1019 $
; socket data structure
struct SOCKET
.PrevPtr dd ? ; pointer to previous socket in list
.NextPtr dd ? ; pointer to next socket in list
.Number dd ? ; socket number (unique within single process)
.PID dd ? ; application process id
.LocalIP dd ? ; local IP address
.LocalPort dw ? ; local port
.RemoteIP dd ? ; remote IP address
.RemotePort dw ? ; remote port
.OrigRemoteIP dd ? ; original remote IP address (used to reset to LISTEN state)
.OrigRemotePort dw ? ; original remote port (used to reset to LISTEN state)
.rxDataCount dd ? ; rx data count
.TCBState dd ? ; TCB state
.TCBTimer dd ? ; TCB timer (seconds)
.ISS dd ? ; initial send sequence
.IRS dd ? ; initial receive sequence
.SND_UNA dd ? ; sequence number of unack'ed sent packets
.SND_NXT dd ? ; bext send sequence number to use
.SND_WND dd ? ; send window
.RCV_NXT dd ? ; next receive sequence number to use
.RCV_WND dd ? ; receive window
.SEG_LEN dd ? ; segment length
.SEG_WND dd ? ; segment window
.wndsizeTimer dd ? ; window size timer
.lock dd ? ; lock mutex
.rxData dd ? ; receive data buffer here
ends
; TCP opening modes
SOCKET_PASSIVE = 0
SOCKET_ACTIVE = 1
; socket types
SOCK_STREAM = 1
SOCK_DGRAM = 2
;; Allocate memory for socket data and put new socket into the list
; Newly created socket is initialized with calling PID and number and
; put into beginning of list (which is a fastest way).
;
; @return socket structure address in EAX
;;
proc net_socket_alloc stdcall uses ebx ecx edx edi
stdcall kernel_alloc, SOCKETBUFFSIZE
DEBUGF 1, "K : net_socket_alloc (0x%x)\n", eax
; check if we can allocate needed amount of memory
or eax, eax
jz .exit
; zero-initialize allocated memory
push eax
mov edi, eax
mov ecx, SOCKETBUFFSIZE / 4
cld
xor eax, eax
rep stosd
pop eax
; add socket to the list by changing pointers
mov ebx, net_sockets
push [ebx + SOCKET.NextPtr]
mov [ebx + SOCKET.NextPtr], eax
mov [eax + SOCKET.PrevPtr], ebx
pop ebx
mov [eax + SOCKET.NextPtr], ebx
or ebx, ebx
jz @f
mov [ebx + SOCKET.PrevPtr], eax
@@: ; set socket owner PID to the one of calling process
mov ebx, [TASK_BASE]
mov ebx, [ebx + TASKDATA.pid]
mov [eax + SOCKET.PID], ebx
; find first free socket number and use it
;mov edx, ebx
mov ebx, net_sockets
xor ecx, ecx
.next_socket_number:
inc ecx
.next_socket:
mov ebx, [ebx + SOCKET.NextPtr]
or ebx, ebx
jz .last_socket_number
cmp [ebx + SOCKET.Number], ecx
jne .next_socket
;cmp [ebx + SOCKET.PID], edx
;jne .next_socket
mov ebx, net_sockets
jmp .next_socket_number
.last_socket_number:
mov [eax + SOCKET.Number], ecx
.exit:
ret
endp
;; Free socket data memory and pop socket off the list
;
; @param sockAddr is a socket structure address
;;
proc net_socket_free stdcall uses ebx ecx edx, sockAddr:DWORD
mov eax, [sockAddr]
DEBUGF 1, "K : net_socket_free (0x%x)\n", eax
; check if we got something similar to socket structure address
or eax, eax
jz .error
; make sure sockAddr is one of the socket addresses in the list
mov ebx, net_sockets
;mov ecx, [TASK_BASE]
;mov ecx, [ecx + TASKDATA.pid]
.next_socket:
mov ebx, [ebx + SOCKET.NextPtr]
or ebx, ebx
jz .error
cmp ebx, eax
jne .next_socket
;cmp [ebx + SOCKET.PID], ecx
;jne .next_socket
; okay, we found the correct one
; remove it from the list first, changing pointers
mov ebx, [eax + SOCKET.NextPtr]
mov eax, [eax + SOCKET.PrevPtr]
mov [eax + SOCKET.NextPtr], ebx
or ebx, ebx
jz @f
mov [ebx + SOCKET.PrevPtr], eax
@@: ; and finally free the memory structure used
stdcall kernel_free, [sockAddr]
ret
.error:
DEBUGF 1, "K : failed\n"
ret
endp
;; Get socket structure address by its number
; Scan through sockets list to find the socket with specified number.
; This proc uses SOCKET.PID indirectly to check if socket is owned by
; calling process.
;
; @param sockNum is a socket number
; @return socket structure address or 0 (not found) in EAX
;;
proc net_socket_num_to_addr stdcall uses ebx ecx, sockNum:DWORD
mov eax, [sockNum]
; check if we got something similar to socket number
or eax, eax
jz .error
; scan through sockets list
mov ebx, net_sockets
;mov ecx, [TASK_BASE]
;mov ecx, [ecx + TASKDATA.pid]
.next_socket:
mov ebx, [ebx + SOCKET.NextPtr]
or ebx, ebx
jz .error
cmp [ebx + SOCKET.Number], eax
jne .next_socket
;cmp [ebx + SOCKET.PID], ecx
;jne .next_socket
; okay, we found the correct one
mov eax, ebx
ret
.error:
xor eax, eax
ret
endp
;; Get socket number by its structure address
; Scan through sockets list to find the socket with specified address.
; This proc uses SOCKET.PID indirectly to check if socket is owned by
; calling process.
;
; @param sockAddr is a socket structure address
; @return socket number (SOCKET.Number) or 0 (not found) in EAX
;;
proc net_socket_addr_to_num stdcall uses ebx ecx, sockAddr:DWORD
mov eax, [sockAddr]
; check if we got something similar to socket structure address
or eax, eax
jz .error
; scan through sockets list
mov ebx, net_sockets
;mov ecx, [TASK_BASE]
;mov ecx, [ecx + TASKDATA.pid]
.next_socket:
mov ebx, [ebx + SOCKET.NextPtr]
or ebx, ebx
jz .error
cmp ebx, eax
jne .next_socket
;cmp [ebx + SOCKET.PID], ecx
;jne .next_socket
; okay, we found the correct one
mov eax, [ebx + SOCKET.Number]
ret
.error:
xor eax, eax
ret
endp
;; [53.9] Check if local port is used by any socket in the system.
; Scan through sockets list, checking SOCKET.LocalPort.
; Useful when you want a to generate a unique local port number.
; This proc doesn't guarantee that after calling it and trying to use
; the port reported being free in calls to socket_open/socket_open_tcp it'll
; still be free or otherwise it'll still be used if reported being in use.
;
; @param BX is a port number
; @return 1 (port is free) or 0 (port is in use) in EAX
;;
proc is_localport_unused stdcall
xchg bl, bh
; assume the return value is 'free'
xor eax, eax
inc al
mov edx, net_sockets
.next_socket:
mov edx, [edx + SOCKET.NextPtr]
or edx, edx
jz .exit
cmp [edx + SOCKET.LocalPort], bx
jne .next_socket
; return 'in use'
dec al
.exit:
ret
endp
;; [53.0] Open DGRAM socket (connectionless, unreliable)
;
; @param BX is local port number
; @param CX is remote port number
; @param EDX is remote IP address
; @return socket number or -1 (error) in EAX
;;
proc socket_open stdcall
call net_socket_alloc
or eax, eax
jz .error
DEBUGF 1, "K : socket_open (0x%x)\n", eax
push eax
xchg bh, bl
mov [eax + SOCKET.LocalPort], bx
xchg ch, cl
mov [eax + SOCKET.RemotePort], cx
mov ebx, [stack_ip]
mov [eax + SOCKET.LocalIP], ebx
mov [eax + SOCKET.RemoteIP], edx
;pop eax ; Get the socket number back, so we can return it
stdcall net_socket_addr_to_num
ret
.error:
DEBUGF 1, "K : socket_open (fail)\n"
or eax, -1
ret
endp
;; [53.5] Open STREAM socket (connection-based, sequenced, reliable, two-way)
;
; @param BX is local port number
; @param CX is remote port number
; @param EDX is remote IP address
; @param ESI is open mode (SOCKET_ACTIVE, SOCKET_PASSIVE)
; @return socket number or -1 (error) in EAX
;;
proc socket_open_tcp stdcall
local sockAddr dd ?
cmp esi, SOCKET_PASSIVE
jne .skip_port_check
push ebx
mov eax, ebx
xchg al, ah
mov ebx, net_sockets
.next_socket:
mov ebx, [ebx + SOCKET.NextPtr]
or ebx, ebx
jz .last_socket
cmp [ebx + SOCKET.TCBState], TCB_LISTEN
jne .next_socket
cmp [ebx + SOCKET.LocalPort], ax
jne .next_socket
xchg al, ah
DEBUGF 1, "K : error: port %u is listened by 0x%x\n", ax, ebx
pop ebx
jmp .error
.last_socket:
pop ebx
.skip_port_check:
call net_socket_alloc
or eax, eax
jz .error
DEBUGF 1, "K : socket_open_tcp (0x%x)\n", eax
mov [sockAddr], eax
; TODO - check this works!
;mov [eax + SOCKET.wndsizeTimer], 0 ; Reset the window timer.
xchg bh, bl
mov [eax + SOCKET.LocalPort], bx
xchg ch, cl
mov [eax + SOCKET.RemotePort], cx
mov [eax + SOCKET.OrigRemotePort], cx
mov ebx, [stack_ip]
mov [eax + SOCKET.LocalIP], ebx
mov [eax + SOCKET.RemoteIP], edx
mov [eax + SOCKET.OrigRemoteIP], edx
mov ebx, TCB_LISTEN
cmp esi, SOCKET_PASSIVE
je @f
mov ebx, TCB_SYN_SENT
@@: mov [eax + SOCKET.TCBState], ebx ; Indicate the state of the TCB
cmp ebx, TCB_LISTEN
je .exit
; Now, if we are in active mode, then we have to send a SYN to the specified remote port
mov eax, EMPTY_QUEUE
call dequeue
cmp ax, NO_BUFFER
je .exit
push eax
mov bl, TH_SYN
xor ecx, ecx
stdcall build_tcp_packet, [sockAddr]
mov eax, NET1OUT_QUEUE
mov edx, [stack_ip]
mov ecx, [sockAddr]
cmp edx, [ecx + SOCKET.RemoteIP]
jne .not_local
mov eax, IPIN_QUEUE
.not_local:
; Send it.
pop ebx
call queue
mov esi, [sockAddr]
; increment SND.NXT in socket
add esi, SOCKET.SND_NXT
call inc_inet_esi
.exit:
; Get the socket number back, so we can return it
stdcall net_socket_addr_to_num, [sockAddr]
ret
.error:
DEBUGF 1, "K : socket_open_tcp (fail)\n"
or eax, -1
ret
endp
;; [53.1] Close DGRAM socket
;
; @param EBX is socket number
; @return 0 (closed successfully) or -1 (error) in EAX
;;
proc socket_close stdcall
DEBUGF 1, "K : socket_close (0x%x)\n", ebx
stdcall net_socket_num_to_addr, ebx
or eax, eax
jz .error
stdcall net_socket_free, eax
xor eax, eax
ret
.error:
DEBUGF 1, "K : socket_close (fail)\n"
or eax, -1
ret
endp
;; [53.8] Close STREAM socket
; Closing TCP sockets takes time, so when you get successful return code
; from this function doesn't always mean that socket is actually closed.
;
; @param EBX is socket number
; @return 0 (closed successfully) or -1 (error) in EAX
;;
proc socket_close_tcp stdcall
local sockAddr dd ?
DEBUGF 1, "K : socket_close_tcp (0x%x)\n", ebx
; first, remove any resend entries
pusha
mov esi, resendQ
mov ecx, 0
.next_resendq:
cmp ecx, NUMRESENDENTRIES
je .last_resendq ; None left
cmp [esi + 4], ebx
je @f ; found one
inc ecx
add esi, 8
jmp .next_resendq
@@: mov dword[esi + 4], 0
inc ecx
add esi, 8
jmp .next_resendq
.last_resendq:
popa
stdcall net_socket_num_to_addr, ebx
or eax, eax
jz .error
mov ebx, eax
mov [sockAddr], eax
cmp [ebx + SOCKET.TCBState], TCB_LISTEN
je .destroy_tcb
cmp [ebx + SOCKET.TCBState], TCB_SYN_SENT
je .destroy_tcb
; Now construct the response, and queue for sending by IP
mov eax, EMPTY_QUEUE
call dequeue
cmp ax, NO_BUFFER
je .error
push eax
mov bl, TH_FIN
xor ecx, ecx
xor esi, esi
stdcall build_tcp_packet, [sockAddr]
mov ebx, [sockAddr]
; increament SND.NXT in socket
lea esi, [ebx + SOCKET.SND_NXT]
call inc_inet_esi
; Get the socket state
mov eax, [ebx + SOCKET.TCBState]
cmp eax, TCB_SYN_RECEIVED
je .fin_wait_1
cmp eax, TCB_ESTABLISHED
je .fin_wait_1
; assume CLOSE WAIT
; Send a fin, then enter last-ack state
mov [ebx + SOCKET.TCBState], TCB_LAST_ACK
jmp .send
.fin_wait_1:
; Send a fin, then enter finwait2 state
mov [ebx + SOCKET.TCBState], TCB_FIN_WAIT_1
.send:
mov eax, NET1OUT_QUEUE
mov edx, [stack_ip]
mov ecx, [sockAddr]
cmp edx, [ecx + SOCKET.RemoteIP]
jne .not_local
mov eax, IPIN_QUEUE
.not_local:
; Send it.
pop ebx
call queue
jmp .exit
.destroy_tcb:
; Clear the socket variables
stdcall net_socket_free, ebx
.exit:
xor eax, eax
ret
.error:
DEBUGF 1, "K : socket_close_tcp (fail)\n"
or eax, -1
ret
endp
;; [53.2] Poll socket
;
; @param EBX is socket number
; @return count or bytes in rx buffer or 0 (error) in EAX
;;
proc socket_poll stdcall
; DEBUGF 1, "socket_poll(0x%x)\n", ebx
stdcall net_socket_num_to_addr, ebx
or eax, eax
jz .error
mov eax, [eax + SOCKET.rxDataCount]
ret
.error:
xor eax, eax
ret
endp
;; [53.6] Get socket TCB state
;
; @param EBX is socket number
; @return socket TCB state or 0 (error) in EAX
;;
proc socket_status stdcall
;; DEBUGF 1, "socket_status(0x%x)\n", ebx
stdcall net_socket_num_to_addr, ebx
or eax, eax
jz .error
mov eax, [eax + SOCKET.TCBState]
ret
.error:
xor eax, eax
ret
endp
;; [53.3] Get one byte from rx buffer
; This function can return 0 in two cases: if there's one byte read and
; non left, and if an error occured. Behavior should be changed and function
; shouldn't be used for now. Consider using [53.11] instead.
;
; @param EBX is socket number
; @return number of bytes left in rx buffer or 0 (error) in EAX
; @return byte read in BL
;;
proc socket_read stdcall
; DEBUGF 1, "socket_read(0x%x)\n", ebx
stdcall net_socket_num_to_addr, ebx
or eax, eax
jz .error
lea ebx, [eax + SOCKET.lock]
call wait_mutex
mov ebx, eax
mov eax, [ebx + SOCKET.rxDataCount] ; get count of bytes
test eax, eax
jz .error_release
dec eax
mov esi, ebx ; esi is address of socket
mov [ebx + SOCKET.rxDataCount], eax ; store new count
movzx eax, byte[ebx + SOCKET.rxData] ; get the byte
mov ecx, SOCKETBUFFSIZE - SOCKET.rxData - 1
lea edi, [esi + SOCKET.rxData]
lea esi, [edi + 1]
cld
push ecx
shr ecx, 2
rep movsd
pop ecx
and ecx, 3
rep movsb
mov [ebx + SOCKET.lock], 0
mov ebx, eax
ret
.error_release:
mov [ebx + SOCKET.lock], 0
.error:
xor ebx, ebx
ret
endp
;; [53.11] Get specified number of bytes from rx buffer
; Number of bytes in rx buffer can be less than requested size. In this case,
; only available number of bytes is read.
; This function can return 0 in two cases: if there's no data to read, and if
; an error occured. Behavior should be changed.
;
; @param EBX is socket number
; @param ECX is pointer to application buffer
; @param EDX is application buffer size (number of bytes to read)
; @return number of bytes read or 0 (error) in EAX
;;
proc socket_read_packet stdcall
; DEBUGF 1, "socket_read_packet(0x%x)\n", ebx
stdcall net_socket_num_to_addr, ebx ; get real socket address
or eax, eax
jz .error
lea ebx, [eax + SOCKET.lock]
call wait_mutex
mov ebx, eax
mov eax, [ebx + SOCKET.rxDataCount] ; get count of bytes
test eax, eax ; if count of bytes is zero..
jz .exit ; exit function (eax will be zero)
test edx, edx ; if buffer size is zero, copy all data
jz .copy_all_bytes
cmp edx, eax ; if buffer size is larger then the bytes of data, copy all data
jge .copy_all_bytes
sub eax, edx ; store new count (data bytes in buffer - bytes we're about to copy)
mov [ebx + SOCKET.rxDataCount], eax ;
push eax
mov eax, edx ; number of bytes we want to copy must be in eax
call .start_copy ; copy to the application
mov esi, ebx ; now we're going to copy the remaining bytes to the beginning
add esi, SOCKET.rxData ; we dont need to copy the header
mov edi, esi ; edi is where we're going to copy to
add esi, edx ; esi is from where we copy
pop ecx ; count of bytes we have left
push ecx ; push it again so we can re-use it later
shr ecx, 2 ; divide eax by 4
cld
rep movsd ; copy all full dwords
pop ecx
and ecx, 3
rep movsb ; copy remaining bytes
.exit:
mov [ebx + SOCKET.lock], 0
ret ; at last, exit
.error:
xor eax, eax
ret
.copy_all_bytes:
xor esi, esi
mov [ebx + SOCKET.rxDataCount], esi ; store new count (zero)
call .start_copy
mov [ebx + SOCKET.lock], 0
ret
.start_copy:
mov edi, ecx
mov esi, ebx
add esi, SOCKET.rxData ; we dont need to copy the header
mov ecx, eax ; eax is count of bytes
push ecx
shr ecx, 2 ; divide eax by 4
cld ; copy all full dwords
rep movsd
pop ecx
and ecx, 3
rep movsb ; copy the rest bytes
retn ; exit, or go back to shift remaining bytes if any
endp
;; [53.4] Send data through DGRAM socket
;
; @param EBX is socket number
; @param ECX is application data size (number of bytes to send)
; @param EDX is pointer to application data buffer
; @return 0 (sent successfully) or -1 (error) in EAX
;;
proc socket_write stdcall
; DEBUGF 1, "socket_write(0x%x)\n", ebx
stdcall net_socket_num_to_addr, ebx ; get real socket address
or eax, eax
jz .error
mov ebx, eax
mov eax, EMPTY_QUEUE
call dequeue
cmp ax, NO_BUFFER
je .error
; Save the queue entry number
push eax
; save the pointers to the data buffer & size
push edx
push ecx
; convert buffer pointer eax to the absolute address
mov ecx, IPBUFFSIZE
mul ecx
add eax, IPbuffs
mov edx, eax
; So, ebx holds the socket ptr, edx holds the IPbuffer ptr
; Fill in the IP header (some data is in the socket descriptor)
mov eax, [ebx + SOCKET.LocalIP]
mov [edx + IP_PACKET.SourceAddress], eax
mov eax, [ebx + SOCKET.RemoteIP]
mov [edx + IP_PACKET.DestinationAddress], eax
mov [edx + IP_PACKET.VersionAndIHL], 0x45
mov [edx + IP_PACKET.TypeOfService], 0
pop eax ; Get the UDP data length
push eax
add eax, 20 + 8 ; add IP header and UDP header lengths
xchg al, ah
mov [edx + IP_PACKET.TotalLength], ax
xor eax, eax
mov [edx + IP_PACKET.Identification], ax
mov [edx + IP_PACKET.FlagsAndFragmentOffset], 0x0040
mov [edx + IP_PACKET.TimeToLive], 0x20
mov [edx + IP_PACKET.Protocol], PROTOCOL_UDP
; Checksum left unfilled
mov [edx + IP_PACKET.HeaderChecksum], ax
; Fill in the UDP header (some data is in the socket descriptor)
mov ax, [ebx + SOCKET.LocalPort]
mov [edx + 20 + UDP_PACKET.SourcePort], ax
mov ax, [ebx + SOCKET.RemotePort]
mov [edx + 20 + UDP_PACKET.DestinationPort], ax
pop eax
push eax
add eax, 8
xchg al, ah
mov [edx + 20 + UDP_PACKET.Length], ax
; Checksum left unfilled
xor eax, eax
mov [edx + 20 + UDP_PACKET.Checksum], ax
pop ecx ; count of bytes to send
mov ebx, ecx ; need the length later
pop eax ; get callers ptr to data to send
; Get the address of the callers data
mov edi, [TASK_BASE]
add edi, TASKDATA.mem_start
add eax, [edi]
mov esi, eax
mov edi, edx
add edi, 28
cld
rep movsb ; copy the data across
; we have edx as IPbuffer ptr.
; Fill in the UDP checksum
; First, fill in pseudoheader
mov eax, [edx + IP_PACKET.SourceAddress]
mov [pseudoHeader], eax
mov eax, [edx + IP_PACKET.DestinationAddress]
mov [pseudoHeader + 4], eax
mov word[pseudoHeader + 8], PROTOCOL_UDP shl 8 + 0 ; 0 + protocol
add ebx, 8
mov eax, ebx
xchg al, ah
mov [pseudoHeader + 10], ax
mov eax, pseudoHeader
mov [checkAdd1], eax
mov [checkSize1], word 12
mov eax, edx
add eax, 20
mov [checkAdd2], eax
mov eax, ebx
mov [checkSize2], ax ; was eax!! mjh 8/7/02
call checksum
; store it in the UDP checksum ( in the correct order! )
mov ax, [checkResult]
; If the UDP checksum computes to 0, we must make it 0xffff
; (0 is reserved for 'not used')
test ax, ax
jnz @f
mov ax, 0xffff
@@: xchg al, ah
mov [edx + 20 + UDP_PACKET.Checksum], ax
; Fill in the IP header checksum
GET_IHL ecx,edx ; get IP-Header length
stdcall checksum_jb,edx,ecx ; buf_ptr, buf_size
xchg al, ah
mov [edx + IP_PACKET.HeaderChecksum], ax
; Check destination IP address.
; If it is the local host IP, route it back to IP_RX
pop ebx
mov eax, NET1OUT_QUEUE
mov ecx, [edx + SOCKET.RemoteIP]
mov edx, [stack_ip]
cmp edx, ecx
jne .not_local
mov eax, IPIN_QUEUE
.not_local:
; Send it.
call queue
xor eax, eax
ret
.error:
or eax, -1
ret
endp
;; [53.7] Send data through STREAM socket
;
; @param EBX is socket number
; @param ECX is application data size (number of bytes to send)
; @param EDX is pointer to application data buffer
; @return 0 (sent successfully) or -1 (error) in EAX
;;
proc socket_write_tcp stdcall
local sockAddr dd ?
; DEBUGF 1, "socket_write_tcp(0x%x)\n", ebx
stdcall net_socket_num_to_addr, ebx
or eax, eax
jz .error
mov ebx, eax
mov [sockAddr], ebx
; If the sockets window timer is nonzero, do not queue packet
cmp [ebx + SOCKET.wndsizeTimer], 0
jne .error
mov eax, EMPTY_QUEUE
call dequeue
cmp ax, NO_BUFFER
je .error
push eax
; Get the address of the callers data
mov edi, [TASK_BASE]
add edi, TASKDATA.mem_start
add edx, [edi]
mov esi, edx
pop eax
push eax
push ecx
mov bl, TH_ACK
stdcall build_tcp_packet, [sockAddr]
pop ecx
; Check destination IP address.
; If it is the local host IP, route it back to IP_RX
pop ebx
push ecx
mov eax, NET1OUT_QUEUE
mov edx, [stack_ip]
mov ecx, [sockAddr]
cmp edx, [ecx + SOCKET.RemoteIP]
jne .not_local
mov eax, IPIN_QUEUE
.not_local:
pop ecx
push ebx ; save ipbuffer number
call queue
mov esi, [sockAddr]
; increament SND.NXT in socket
; Amount to increment by is in ecx
add esi, SOCKET.SND_NXT
call add_inet_esi
pop ebx
; Copy the IP buffer to a resend queue
; If there isn't one, dont worry about it for now
mov esi, resendQ
mov ecx, 0
.next_resendq:
cmp ecx, NUMRESENDENTRIES
je .exit ; None found
cmp dword[esi + 4], 0
je @f ; found one
inc ecx
add esi, 8
jmp .next_resendq
@@: push ebx
; OK, we have a buffer descriptor ptr in esi.
; resend entry # in ecx
; Populate it
; socket #
; retries count
; retry time
; fill IP buffer associated with this descriptor
stdcall net_socket_addr_to_num, [sockAddr]
mov [esi + 4], eax
mov byte[esi + 1], TCP_RETRIES
mov word[esi + 2], TCP_TIMEOUT
inc ecx
; Now get buffer location, and copy buffer across. argh! more copying,,
mov edi, resendBuffer - IPBUFFSIZE
@@: add edi, IPBUFFSIZE
loop @b
; we have dest buffer location in edi
pop eax
; convert source buffer pointer eax to the absolute address
mov ecx, IPBUFFSIZE
mul ecx
add eax, IPbuffs
mov esi, eax
; do copy
mov ecx, IPBUFFSIZE
cld
rep movsb
.exit:
xor eax, eax
ret
.error:
or eax, -1
ret
endp