kolibrios/kernel/trunk/network/ARP.inc

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;                                                                 ;;
;; Copyright (C) KolibriOS team 2004-2013. 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                               ;;
;;                                                                 ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

$Revision: 3386 $

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

align 4
uglobal

        NumARP          dd ?

        ARP_table       rb ARP_TABLE_SIZE * sizeof.ARP_entry    ; TODO: separate ARP table and stats per interface

        ARP_PACKETS_TX  rd NET_DEVICES_MAX
        ARP_PACKETS_RX  rd NET_DEVICES_MAX
        ARP_CONFLICTS   rd NET_DEVICES_MAX


endg



;-----------------------------------------------------------------
;
; ARP_init
;
;  This function resets all ARP variables
;
;-----------------------------------------------------------------
macro ARP_init {

        xor     eax, eax
        mov     [NumARP], eax

        mov     edi, ARP_PACKETS_TX
        mov     ecx, 3*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

        mov     ecx, [NumARP]
        test    ecx, ecx
        jz      .exit

        mov     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 ecx
        call    ARP_del_entry
        pop     ecx esi

        jmp     .next

  .response_timeout:
        mov     [esi + ARP_entry.Status], ARP_RESPONSE_TIMEOUT
        mov     [esi + ARP_entry.TTL], 10

        jmp     .next

  .exit:

}


;-----------------------------------------------------------------
;
; ARP_input
;
;  IN:  Pointer to buffer in [esp]
;       size of buffer in [esp+4]
;       packet size (without ethernet header) in ecx
;       packet ptr in edx
;       device ptr in ebx
;  OUT: /
;
;-----------------------------------------------------------------
align 4
ARP_input:

;-----------------------------------------
; Check validity and print some debug info

        cmp     ecx, sizeof.ARP_header
        jb      .exit

        call    NET_ptr_to_num
        cmp     edi, -1
        jz      .exit

        inc     [ARP_PACKETS_RX + 4*edi]        ; update stats

        DEBUGF  DEBUG_NETWORK_VERBOSE, "ARP_input: got packet from %u.%u.%u.%u through device %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, [IP_LIST + 4*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, [NumARP]
        test    ecx, ecx
        jz      .exit

        mov     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, [IP_LIST + 4*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_DRV_LIST + 4*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]
        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 + 4*edi]
        DEBUGF  DEBUG_NETWORK_VERBOSE, "ARP_input: IP address conflict detected!\n"

  .exit:
        call    kernel_free
        add     esp, 4                                          ; pop (balance stack)

        DEBUGF  DEBUG_NETWORK_VERBOSE, "ARP_input: exiting\n"
        ret


;---------------------------------------------------------------------------
;
; ARP_output_request
;
; IN:  ip in eax
;      device in edi
; OUT: /
;
;---------------------------------------------------------------------------
align 4
ARP_output_request:

        push    eax                             ; DestIP
        pushd   [IP_LIST + edi]                 ; SenderIP
        inc     [ARP_PACKETS_TX + edi]          ; assume we will succeed

        DEBUGF  DEBUG_NETWORK_VERBOSE, "ARP_output_request: ip=%u.%u.%u.%u\n",\
        [esp + 4]:1, [esp + 5]:1, [esp + 6]:1, [esp + 7]:1

        mov     ebx, [NET_DRV_LIST + edi]       ; device ptr

        lea     eax, [ebx + ETH_DEVICE.mac]     ; local device mac
        mov     edx, ETH_BROADCAST              ; broadcast mac
        mov     ecx, sizeof.ARP_header
        mov     di, ETHER_PROTO_ARP
        call    ETH_output
        jz      .exit

        mov     ecx, eax

        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                                   ;
        pop     eax                             ; SenderIP
        stosd                                   ;

        mov     eax, -1                         ; DestMac
        stosd                                   ;
        stosw                                   ;
        pop     eax                             ; DestIP
        stosd                                   ;

        DEBUGF  DEBUG_NETWORK_VERBOSE, "ARP_output_request: device=%x\n", ebx

        push    edx ecx
        call    [ebx + NET_DEVICE.transmit]
        ret

  .exit:
        add     esp, 4 + 4
        DEBUGF  DEBUG_NETWORK_VERBOSE, "ARP_output_request: failed\n"
        sub     eax, eax
        ret


;-----------------------------------------------------------------
;
; ARP_add_entry (or update)
;
; IN:  esi = ptr to entry (can easily be made on the stack)
; OUT: eax = entry #, -1 on error
;      edi = ptr to newly created entry
;
;-----------------------------------------------------------------      ; TODO: use a mutex
align 4
ARP_add_entry:

        DEBUGF  DEBUG_NETWORK_VERBOSE, "ARP_add_entry: "

        mov     ecx, [NumARP]
        cmp     ecx, ARP_TABLE_SIZE                                     ; list full ?
        jae     .error

        xor     eax, eax
        mov     edi, ARP_table
        mov     ecx, [esi + ARP_entry.IP]
  .loop:
        cmp     [edi + ARP_entry.Status], ARP_NO_ENTRY                  ; is this slot empty?
        je      .add

        cmp     [edi + ARP_entry.IP], ecx                               ; 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

  .maybe_next:                                                          ; try the next slot
        add     edi, sizeof.ARP_entry
        inc     eax
        cmp     eax, ARP_TABLE_SIZE
        jae     .error
        jmp     .loop

  .add:
        mov     ecx, sizeof.ARP_entry/2
        rep     movsw
        inc     [NumARP]
        sub     edi, sizeof.ARP_entry
        DEBUGF  DEBUG_NETWORK_VERBOSE, "entry=%u\n", eax

        ret

  .error:
        DEBUGF  DEBUG_NETWORK_VERBOSE, "failed\n"
        mov     eax, -1
        ret


;-----------------------------------------------------------------
;
; ARP_del_entry
;
; IN:  esi = ptr to arp entry
; OUT: /
;
;-----------------------------------------------------------------
align 4
ARP_del_entry:

        DEBUGF  DEBUG_NETWORK_VERBOSE, "ARP_del_entry: entry=%x entrys=%u\n", esi, [NumARP]
        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

        mov     ecx, ARP_table + (ARP_TABLE_SIZE - 1) * sizeof.ARP_entry
        sub     ecx, esi
        shr     ecx, 1

        mov     edi, esi
        add     esi, sizeof.ARP_entry
        rep     movsw

        xor     eax, eax
        mov     ecx, sizeof.ARP_entry/2
        rep     stosw

        dec     [NumARP]
        DEBUGF  DEBUG_NETWORK_VERBOSE, "ARP_del_entry: success\n"

        ret





;-----------------------------------------------------------------
;
; ARP_IP_to_MAC
;
;  This function translates an IP address to a MAC address
;
;  IN:  eax = IPv4 address
;       edi = device number
;  OUT: eax = -1 on error, -2 means request send
;      else, ax = first two bytes of mac (high 16 bits of eax will be 0)
;       ebx = last four bytes of mac
;       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\n", al, ah
        rol     eax, 16

        cmp     eax, 0xffffffff
        je      .broadcast

;--------------------------------
; Try to find the IP in ARP_table

        mov     ecx, [NumARP]
        test    ecx, ecx
        jz      .not_in_list
        mov     esi, ARP_table + ARP_entry.IP
  .scan_loop:
        cmp     [esi], eax
        je      .found_it
        add     esi, sizeof.ARP_entry
        loop    .scan_loop

  .not_in_list:
        DEBUGF  DEBUG_NETWORK_VERBOSE, "ARP_IP_to_MAC: preparing for ARP request\n"

;--------------------
; Send an ARP request

        push    eax edi                 ; save IP for ARP_output_request

; Now create the ARP entry
        pushw   ARP_REQUEST_TTL         ; TTL
        pushw   ARP_AWAITING_RESPONSE   ; status
        pushd   0                       ; mac
        pushw   0
        pushd   eax                     ; ip
        mov     esi, esp
        call    ARP_add_entry
        add     esp, sizeof.ARP_entry   ; clear the entry from stack

        cmp     eax, -1                 ; did ARP_add_entry fail?
        je      .full

        mov     esi, edi
        pop     edi eax                 ; IP in eax, device number in edi, for ARP_output_request

        push    esi edi
        call    ARP_output_request      ; And send a request
        pop     edi esi

;-----------------------------------------------
; At this point, we got an ARP entry in the list
  .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
;
; 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
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, [NumARP]
        ret

  .read:
        cmp     ecx, [NumARP]
        jae     .error
        ; edi = pointer to buffer
        ; ecx = # entry
        imul    ecx, sizeof.ARP_entry
        add     ecx, ARP_table
        mov     esi, ecx
        mov     ecx, sizeof.ARP_entry/2
        rep     movsw

        xor     eax, eax
        ret

  .write:
        ; esi = pointer to buffer
        call    ARP_add_entry           ; out: eax = entry number, -1 on error
        ret

  .remove:
        ; ecx = # entry
        cmp     ecx, [NumARP]
        jae     .error
        imul    ecx, sizeof.ARP_entry
        lea     esi, [ARP_table + ecx]
        call    ARP_del_entry
        ret

  .send_announce:
        mov     edi, eax
        mov     eax, [IP_LIST + eax]
        call    ARP_output_request      ; now send a gratuitous ARP
        ret