;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; ;; ;; Copyright (C) KolibriOS team 2004-2024. All rights reserved. ;; ;; Distributed under terms of the GNU General Public License ;; ;; ;; ;; ARP.INC ;; ;; ;; ;; Part of the tcp/ip network stack for KolibriOS ;; ;; ;; ;; Based on the work of [Johnny_B] and [smb] ;; ;; ;; ;; Written by hidnplayr@kolibrios.org ;; ;; ;; ;; GNU GENERAL PUBLIC LICENSE ;; ;; Version 2, June- 1991 ;; ;; ;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ARP_NO_ENTRY = 0 ARP_VALID_MAPPING = 1 ARP_AWAITING_RESPONSE = 2 ARP_RESPONSE_TIMEOUT = 3 ARP_REQUEST_TTL = 31 ; 20 s ARP_ENTRY_TTL = 937 ; 600 s ARP_STATIC_ENTRY = -1 ARP_REQ_OPCODE = 0x0100 ; request ARP_REP_OPCODE = 0x0200 ; reply ARP_TABLE_SIZE = 20 ; Size of table struct ARP_entry IP dd ? MAC dp ? Status dw ? TTL dw ? ends struct ARP_header HardwareType dw ? ProtocolType dw ? HardwareSize db ? ProtocolSize db ? Opcode dw ? SenderMAC dp ? SenderIP dd ? TargetMAC dp ? TargetIP dd ? ends uglobal align 4 ARP_table rb NET_DEVICES_MAX*(ARP_TABLE_SIZE * sizeof.ARP_entry) ARP_entries rd NET_DEVICES_MAX ARP_packets_tx rd NET_DEVICES_MAX ARP_packets_rx rd NET_DEVICES_MAX ARP_conflicts rd NET_DEVICES_MAX endg ;-----------------------------------------------------------------; ; ; ; arp_init: Resets all ARP variables. ; ; ; ;-----------------------------------------------------------------; macro arp_init { xor eax, eax mov edi, ARP_entries mov ecx, 4*NET_DEVICES_MAX rep stosd } ;-----------------------------------------------------------------; ; ; ; arp_decrease_entry_ttls ; ; ; ;-----------------------------------------------------------------; macro arp_decrease_entry_ttls { local .loop local .exit ; The TTL field is decremented every second, and is deleted when it reaches 0. ; It is refreshed every time a packet is received. ; If the TTL field is 0xFFFF it is a static entry and is never deleted. ; The status field can be the following values: ; 0x0000 entry not used ; 0x0001 entry holds a valid mapping ; 0x0002 entry contains an IP address, awaiting ARP response ; 0x0003 No response received to ARP request. ; The last status value is provided to allow the network layer to delete ; a packet that is queued awaiting an ARP response xor edi, edi .loop_outer: mov ecx, [ARP_entries + 4*edi] test ecx, ecx jz .exit mov esi, (ARP_TABLE_SIZE * sizeof.ARP_entry) imul esi, edi add esi, ARP_table .loop: cmp [esi + ARP_entry.TTL], ARP_STATIC_ENTRY je .next dec [esi + ARP_entry.TTL] jz .time_out .next: add esi, sizeof.ARP_entry dec ecx jnz .loop jmp .exit .time_out: cmp [esi + ARP_entry.Status], ARP_AWAITING_RESPONSE je .response_timeout push esi edi ecx call arp_del_entry pop ecx edi esi jmp .next .response_timeout: mov [esi + ARP_entry.Status], ARP_RESPONSE_TIMEOUT mov [esi + ARP_entry.TTL], 10 jmp .next .exit: inc edi cmp edi, NET_DEVICES_MAX jb .loop_outer } ;-----------------------------------------------------------------; ; ; ; arp_input ; ; ; ; IN: [esp] = Pointer to buffer ; ; [esp+4] = size of buffer ; ; ecx = packet size (without ethernet header) ; ; edx = packet ptr ; ; ebx = device ptr ; ; ; ; OUT: / ; ; ; ;-----------------------------------------------------------------; align 4 arp_input: ;----------------------------------------- ; Check validity and print some debug info cmp ecx, sizeof.ARP_header jb .exit call net_ptr_to_num4 cmp edi, -1 jz .exit inc [ARP_packets_rx + edi] ; update stats DEBUGF DEBUG_NETWORK_VERBOSE, "ARP_input: got packet from %u.%u.%u.%u (device*4=%u)\n",\ [edx + ARP_header.SenderIP]:1, [edx + ARP_header.SenderIP + 1]:1,\ [edx + ARP_header.SenderIP + 2]:1, [edx + ARP_header.SenderIP + 3]:1, edi ;------------------------------ ; First, check for IP collision mov eax, [edx + ARP_header.SenderIP] cmp eax, [IPv4_address + edi] je .collision ;--------------------- ; Handle reply packets cmp [edx + ARP_header.Opcode], ARP_REP_OPCODE jne .maybe_request DEBUGF DEBUG_NETWORK_VERBOSE, "ARP_input: It's a reply\n" mov ecx, [ARP_entries + edi] test ecx, ecx jz .exit mov esi, edi imul esi, (ARP_TABLE_SIZE * sizeof.ARP_entry)/4 add esi, ARP_table .loop: cmp [esi + ARP_entry.IP], eax je .gotit add esi, sizeof.ARP_entry dec ecx jnz .loop DEBUGF DEBUG_NETWORK_VERBOSE, "ARP_input: no matching entry found\n" jmp .exit .gotit: DEBUGF DEBUG_NETWORK_VERBOSE, "ARP_input: found matching entry\n" cmp [esi + ARP_entry.TTL], ARP_STATIC_ENTRY ; if it is a static entry, dont touch it je .exit DEBUGF DEBUG_NETWORK_VERBOSE, "ARP_input: updating entry\n" mov [esi + ARP_entry.Status], ARP_VALID_MAPPING mov [esi + ARP_entry.TTL], ARP_ENTRY_TTL mov eax, dword [edx + ARP_header.SenderMAC] mov dword [esi + ARP_entry.MAC], eax mov cx, word [edx + ARP_header.SenderMAC + 4] mov word [esi + ARP_entry.MAC + 4], cx jmp .exit ;----------------------- ; Handle request packets .maybe_request: cmp [edx + ARP_header.Opcode], ARP_REQ_OPCODE jne .exit DEBUGF DEBUG_NETWORK_VERBOSE, "ARP_input: its a request\n" mov eax, [IPv4_address + edi] cmp eax, [edx + ARP_header.TargetIP] ; Is it looking for my IP address? jne .exit push eax push edi ; OK, it is a request for one of our MAC addresses. ; Build the frame and send it. We can reuse the buffer. (faster then using ARP_create_packet) lea esi, [edx + ARP_header.SenderMAC] lea edi, [edx + ARP_header.TargetMAC] movsd ; Move Sender Mac to Dest MAC movsw ; movsd ; Move sender IP to Dest IP pop esi mov esi, [net_device_list + esi] lea esi, [esi + ETH_DEVICE.mac] lea edi, [edx + ARP_header.SenderMAC] movsd ; Copy MAC address from in MAC_LIST movsw ; pop eax stosd ; Write our IP mov [edx + ARP_header.Opcode], ARP_REP_OPCODE ; Now, Fill in ETHERNET header mov edi, [esp] add edi, [edi + NET_BUFF.offset] lea esi, [edx + ARP_header.TargetMAC] movsd movsw lea esi, [edx + ARP_header.SenderMAC] movsd movsw ; mov ax , ETHER_ARP ; It's already there, I'm sure of it! ; stosw DEBUGF DEBUG_NETWORK_VERBOSE, "ARP_input: Sending reply\n" call [ebx + NET_DEVICE.transmit] ret .collision: inc [ARP_conflicts + edi] DEBUGF DEBUG_NETWORK_VERBOSE, "ARP_input: IP address conflict detected!\n" .exit: DEBUGF DEBUG_NETWORK_VERBOSE, "ARP_input: exiting\n" call net_buff_free ret ;-----------------------------------------------------------------; ; ; ; arp_output_request ; ; ; ; IN: ebx = device ptr ; ; eax = IP ; ; ; ; OUT: scratched: probably everything ; ; ; ;-----------------------------------------------------------------; align 4 arp_output_request: push eax DEBUGF DEBUG_NETWORK_VERBOSE, "ARP_output_request: ip=%u.%u.%u.%u device=0x%x\n",\ [esp]:1, [esp + 1]:1, [esp + 2]:1, [esp + 3]:1, ebx mov ax, ETHER_PROTO_ARP mov ecx, sizeof.ARP_header mov edx, ETH_BROADCAST ; broadcast mac call eth_output jz .exit mov [edi + ARP_header.HardwareType], 0x0100 ; Ethernet mov [edi + ARP_header.ProtocolType], 0x0008 ; IP mov [edi + ARP_header.HardwareSize], 6 ; MAC-addr length mov [edi + ARP_header.ProtocolSize], 4 ; IP-addr length mov [edi + ARP_header.Opcode], ARP_REQ_OPCODE ; Request add edi, ARP_header.SenderMAC lea esi, [ebx + ETH_DEVICE.mac] ; SenderMac movsw ; movsd ; push edi call net_ptr_to_num4 inc [ARP_packets_tx + edi] ; assume we will succeed lea esi, [IPv4_address + edi] ; SenderIP pop edi movsd mov esi, ETH_BROADCAST ; DestMac movsw ; movsd ; popd [edi] ; DestIP push eax call [ebx + NET_DEVICE.transmit] ret .exit: add esp, 4 DEBUGF DEBUG_NETWORK_ERROR, "ARP_output_request: send failed\n" ret ;-----------------------------------------------------------------; ; ; ; arp_add_entry: Add or update an entry in the ARP table. ; ; ; ; IN: esi = ptr to entry (can easily be made on the stack) ; ; edi = device num*4 ; ; ; ; OUT: eax = entry number on success ; ; eax = -1 on error ; ; esi = ptr to newly created entry ; ; ; ;-----------------------------------------------------------------; align 4 arp_add_entry: ; TODO: use a mutex to lock ARP table DEBUGF DEBUG_NETWORK_VERBOSE, "ARP_add_entry: device=%u\n", edi mov ecx, [ARP_entries + edi] cmp ecx, ARP_TABLE_SIZE ; list full ? jae .full ; From this point on, we can only fail if IP has a static entry, or if table is corrupt. inc [ARP_entries + edi] ; assume we will succeed push edi xor ecx, ecx imul edi, ARP_TABLE_SIZE*sizeof.ARP_entry/4 add edi, ARP_table mov eax, [esi + ARP_entry.IP] .loop: cmp [edi + ARP_entry.Status], ARP_NO_ENTRY ; is this slot empty? je .add cmp [edi + ARP_entry.IP], eax ; if not, check if it doesnt collide jne .maybe_next cmp [edi + ARP_entry.TTL], ARP_STATIC_ENTRY ; ok, its the same IP, update it if not static jne .add DEBUGF DEBUG_NETWORK_ERROR, "ARP_add_entry: failed, IP already has a static entry\n" jmp .error .maybe_next: ; try the next slot add edi, sizeof.ARP_entry inc ecx cmp ecx, ARP_TABLE_SIZE jb .loop .add: push ecx mov ecx, sizeof.ARP_entry/2 rep movsw pop ecx lea esi, [edi - sizeof.ARP_entry] pop edi DEBUGF DEBUG_NETWORK_VERBOSE, "ARP_add_entry: entry=%u\n", ecx ret .error: pop edi dec [ARP_entries + edi] DEBUGF DEBUG_NETWORK_ERROR, "ARP_add_entry_failed\n" .full: mov eax, -1 ret ;-----------------------------------------------------------------; ; ; ; arp_del_entry: Remove an entry from the ARP table. ; ; ; ; IN: esi = ptr to arp entry ; ; edi = device number ; ; ; ; OUT: / ; ; ; ;-----------------------------------------------------------------; align 4 arp_del_entry: ; TODO: use a mutex to lock ARP table DEBUGF DEBUG_NETWORK_VERBOSE, "ARP_del_entry: entry=0x%x entrys=%u\n", esi, [ARP_entries + 4*edi] DEBUGF DEBUG_NETWORK_VERBOSE, "ARP_del_entry: IP=%u.%u.%u.%u\n", \ [esi + ARP_entry.IP]:1, [esi + ARP_entry.IP + 1]:1, [esi + ARP_entry.IP + 2]:1, [esi + ARP_entry.IP + 3]:1 push edi imul edi, (ARP_TABLE_SIZE) * sizeof.ARP_entry lea ecx, [ARP_table + (ARP_TABLE_SIZE - 1) * sizeof.ARP_entry + edi] sub ecx, esi shr ecx, 1 ; move all trailing entries, sizeof.ARP_entry bytes to left. mov edi, esi add esi, sizeof.ARP_entry rep movsw ; now add an empty entry to the end (erasing previous one) xor eax, eax mov ecx, sizeof.ARP_entry/2 rep stosw pop edi dec [ARP_entries + 4*edi] DEBUGF DEBUG_NETWORK_VERBOSE, "ARP_del_entry: success\n" ret ;-----------------------------------------------------------------; ; ; ; arp_ip_to_mac: Translate an IP address to a MAC address. ; ; ; ; IN: eax = IPv4 address ; ; edi = device number * 4 ; ; ; ; OUT: eax = -1 on error ; ; eax = -2 when request send ; ; eax = first two bytes of mac on success ; ; ebx = last four bytes of mac on success ; ; edi = unchanged ; ; ; ;-----------------------------------------------------------------; align 4 arp_ip_to_mac: DEBUGF DEBUG_NETWORK_VERBOSE, "ARP_IP_to_MAC: %u.%u", al, ah rol eax, 16 DEBUGF DEBUG_NETWORK_VERBOSE, ".%u.%u device*4: %u\n", al, ah, edi rol eax, 16 cmp eax, 0xffffffff je .broadcast ;-------------------------------- ; Try to find the IP in ARP_table mov ecx, [ARP_entries + edi] test ecx, ecx jz .not_in_list mov esi, edi imul esi, (sizeof.ARP_entry * ARP_TABLE_SIZE)/4 add esi, ARP_table + ARP_entry.IP .scan_loop: cmp [esi], eax je .found_it add esi, sizeof.ARP_entry dec ecx jnz .scan_loop .not_in_list: DEBUGF DEBUG_NETWORK_VERBOSE, "ARP_IP_to_MAC: preparing for ARP request\n" push eax edi ; save IP for ARP_output_request ; Now craft the ARP entry on the stack pushw ARP_REQUEST_TTL ; TTL pushw ARP_AWAITING_RESPONSE ; status pushd 0 ; mac pushw 0 pushd eax ; IP mov esi, esp ; Add it to the list call arp_add_entry ; Delete the temporary entry add esp, sizeof.ARP_entry ; clear the entry from stack ; If we could not add it to the list, give up cmp eax, -1 ; did ARP_add_entry fail? je .full ;----------------------------------------------- ; At this point, we got an ARP entry in the list ; Now send a request packet on the network pop edi eax ; IP in eax, device number in ebx, for ARP_output_request push esi edi mov ebx, [net_device_list + edi] call arp_output_request pop edi esi .found_it: cmp [esi + ARP_entry.Status], ARP_VALID_MAPPING ; Does it have a MAC assigned? je .valid if ARP_BLOCK cmp [esi + ARP_entry.Status], ARP_AWAITING_RESPONSE ; Are we waiting for reply from remote end? jne .give_up push esi mov esi, 10 ; wait 10 ms call delay_ms pop esi jmp .found_it ; now check again else jmp .give_up end if .valid: DEBUGF DEBUG_NETWORK_VERBOSE, "ARP_IP_to_MAC: found MAC\n" movzx eax, word[esi + ARP_entry.MAC] mov ebx, dword[esi + ARP_entry.MAC + 2] ret .full: DEBUGF DEBUG_NETWORK_VERBOSE, "ARP_IP_to_MAC: table is full!\n" add esp, 8 .give_up: DEBUGF DEBUG_NETWORK_VERBOSE, "ARP_IP_to_MAC: entry has no valid mapping!\n" mov eax, -1 ret .broadcast: mov eax, 0x0000ffff mov ebx, 0xffffffff ret ;-----------------------------------------------------------------; ; ; ; arp_api: Part of system function 76. ; ; ; ; IN: bl = subfunction number ; ; bh = device number ; ; ecx, edx, .. depends on subfunction ; ; ; ; OUT: depends on subfunction ; ; ; ;-----------------------------------------------------------------; align 4 arp_api: movzx eax, bh shl eax, 2 and ebx, 0xff cmp ebx, .number ja .error jmp dword [.table + 4*ebx] .table: dd .packets_tx ; 0 dd .packets_rx ; 1 dd .entries ; 2 dd .read ; 3 dd .write ; 4 dd .remove ; 5 dd .send_announce ; 6 dd .conflicts ; 7 .number = ($ - .table) / 4 - 1 .error: mov eax, -1 ret .packets_tx: mov eax, [ARP_packets_tx + eax] ret .packets_rx: mov eax, [ARP_packets_rx + eax] ret .conflicts: mov eax, [ARP_conflicts + eax] ret .entries: mov eax, [ARP_entries + eax] ret .read: cmp ecx, [ARP_entries + eax] jae .error shr eax, 2 imul eax, sizeof.ARP_entry*ARP_TABLE_SIZE add eax, ARP_table ; edi = pointer to buffer ; ecx = # entry imul ecx, sizeof.ARP_entry lea esi, [eax + ecx] mov ecx, sizeof.ARP_entry/2 rep movsw xor eax, eax ret .write: ; esi = pointer to buffer mov edi, eax call arp_add_entry ; out: eax = entry number, -1 on error ret .remove: ; ecx = # entry cmp ecx, [ARP_entries + eax] jae .error imul ecx, sizeof.ARP_entry lea esi, [ARP_table + ecx] mov edi, eax shr edi, 2 call arp_del_entry ret .send_announce: mov ebx, [net_device_list + eax] mov eax, [IPv4_address + eax] call arp_output_request ; now send a gratuitous ARP ret