; ****************************************************************************
;
+; Macros for byte order
+;
+%define htons(x) ( ( ((x) & 0FFh) << 8 ) + ( ((x) & 0FF00h) >> 8 ) )
+%define ntohs(x) htons(x)
+%define htonl(x) ( ( ((x) & 0FFh) << 24) + ( ((x) & 0FF00h) << 8 ) + ( ((x) & 0FF0000h) >> 8 ) + ( ((x) & 0FF000000h) >> 24) )
+%define ntohl(x) htonl(x)
+
+;
; Some semi-configurable constants... change on your own risk. Most are imposed
; by the kernel.
;
HIGHMEM_MAX equ 038000000h ; Highest address for an initrd
DEFAULT_BAUD equ 9600 ; Default baud rate for serial port
BAUD_DIVISOR equ 115200 ; Serial port parameter
+MAX_SOCKETS equ 64 ; Max number of open sockets
+TFTP_PORT equ htons(69) ; Default TFTP port
+PKT_RETRY equ 8 ; Packet transmit retry count
+PKT_TIMEOUT equ 20 ; Timer ticks @ 55 ms
+
+;
+; TFTP operation codes
+;
+TFTP_RRQ equ htons(1) ; Read request
+TFTP_WRQ equ htons(2) ; Write request
+TFTP_DATA equ htons(3) ; Data packet
+TFTP_ACK equ htons(4) ; ACK packet
+TFTP_ERROR equ htons(5) ; ERROR packet
+
;
; Should be updated with every release to avoid bootsector/SYS file mismatch
;
; Segments used by Linux
;
; Note: the real_mode_seg is supposed to be 9000h, but PXE uses that
-; memory. Therefore, we load it at 8000h and copy it before starting
+; memory. Therefore, we load it at 5000:0000h and copy it before starting
; the Linux kernel.
;
-real_mode_seg equ 7000h
+real_mode_seg equ 5000h
struc real_mode_seg_t
resb 20h-($-$$) ; org 20h
kern_cmd_magic resw 1 ; Magic # for command line
;
; Segment assignments in the bottom 640K
; 0000h - main code/data segment (and BIOS segment)
-; 7000h - real_mode_seg
+; 5000h - real_mode_seg
;
-vk_seg equ 6000h ; This is where we stick'em
-xfer_buf_seg equ 5000h ; Bounce buffer for I/O to high mem
-fat_seg equ 3000h ; 128K area for FAT (2x64K)
+vk_seg equ 4000h ; This is where we stick'em
+xfer_buf_seg equ 3000h ; Bounce buffer for I/O to high mem
comboot_seg equ 2000h ; COMBOOT image loading zone
+fat_seg equ 0h ; BOGUS
+
+;
+; TFTP connection data structure. Each one of these corresponds to a local
+; UDP port. The size of this structure must be a power of 2.
+;
+ struc tftp_port_t
+tftp_localport resw 1 ; Local port number (0 = not in use)
+tftp_remoteport resw 1 ; Remote port number
+tftp_localip resd 1 ; Local IP address
+tftp_remoteip resd 1 ; Remote IP address
+tftp_filepos resd 1 ; Position within file
+ endstruc
+
+%if (tftp_port_t_size & (tftp_port_t_size-1))
+%error "tftp_port_t is not a power of 2"
+%endif
+
;
; For our convenience: define macros for jump-over-unconditinal jumps
;
; Memory below this point is reserved for the BIOS and the MBR
;
absolute 1000h
-trackbuf equ $ ; Track buffer goes here
-trackbufsize equ 16384 ; Safe size of track buffer
+trackbuf resb 16384 ; Track buffer goes here
+trackbufsize equ $-trackbuf
+
; trackbuf ends at 5000h
- absolute 6000h ; Here we keep our BSS stuff
+ absolute 5000h ; Here we keep our BSS stuff
StackBuf equ $ ; Start the stack here (grow down - 4K)
VKernelBuf: resb vk_size ; "Current" vkernel
alignb 4
KernelSize resd 1 ; Size of kernel (bytes)
Stack resd 1 ; Pointer to reset stack
PXEEntry resd 1 ; !PXE API entry point
+ServerIP resd 1 ; IP address of boot server
RootDir equ $ ; Location of root directory
RootDir1 resw 1
RootDir2 resw 1
SetupSecs resw 1 ; Number of setup sectors
SavedSP resw 1 ; Our SP while running a COMBOOT image
A20Test resw 1 ; Counter for testing status of A20
+ServerPort resw 1 ; TFTP server port
+CurrentSocket resw 1 ; Workspace for network functions
TextAttrBX equ $
TextAttribute resb 1 ; Text attribute for message file
TextPage resb 1 ; Active display page
MNameBuf resb 11 ; OBSOLETE
InitRD resb 11 ; OBSOLETE
+ alignb tftp_port_t_size
+Sockets resb MAX_SOCKETS*tftp_port_t_size
+
alignb 16
; BOOTP/DHCP packet buffer
bootp:
bootp_size equ $-bootp
+ alignb 16
+packet_buf resb 2048 ; Transfer packet
+packet_buf_size equ $-packet_buf
section .text
org 7C00h
call crlf
;
+; Initialize screen (if we're using one)
+;
+ call adjust_screen
+
+;
; Tell the user we got this far
;
mov si,pxelinux_banner
mov si,copyright_str
call writestr
-
+
+;
+; Clear Sockets structures
+;
+ mov di,Sockets
+ mov cx,(MAX_SOCKETS*tftp_port_t_size)/4
+ xor eax,eax
+ rep stosd
+
;
; Now attempt to get the BOOTP/DHCP packet that brought us life (and an IP
; address)
mov si,bootp.bootfile
call writestr
call crlf
+
;
; Normalize ES = DS
;
mov ax,ds
mov es,ax
+
;
-; Now, prepare some of the data structures
+; Save away the server IP and port number
;
mov eax,[bootp.sip]
- mov [pxe_tftp_open_pkt.sip],eax
+ mov [ServerIP],eax
+ mov [ServerPort], word TFTP_PORT
+;
+; Initialize UDP stack
+;
+udp_init:
+ mov eax,[bootp.yip]
+ mov [pxe_udp_open_pkt.sip],eax
+ mov di,pxe_udp_open_pkt
+ mov bx,0030h ; PXENV_UDP_OPEN
+ call far [PXENVEntry]
+ jc .failed
+ cmp word [pxe_udp_open_pkt.status], byte 0
+ je .success
+.failed: mov si,err_udpinit
+ call writestr
+ jmp kaboom
+.success:
+
+;
+; Now, prepare some of the data structures
+;
filename_cp: mov si,bootp.bootfile
mov di,pxe_tftp_open_pkt.filename
cld
.nodot: mov di,si
.dot: cld
; Now di points to where we want to add stuff to the filename
- mov al,'/'
- stosb
+ mov si,dot_cfg_slash
+ mov cx,dot_cfg_slash_len
+ rep movsb
mov cx,8
mov eax,[bootp.yip]
bswap eax ; Convert to native byte order
rep movsb ; Copy "default" string
popa
.not_default: pusha
- mov di,pxe_tftp_open_pkt
- mov bx,0020h ; PXENV_TFTP_OPEN
- call far [PXENVEntry]
- jc .badness
- cmp ax,byte 0
- jne .badness
- cmp word [pxe_tftp_open_pkt.status],0
- je .success
+ mov si,trying_msg
+ call writestr
+ mov si,pxe_tftp_open_pkt.filename
+ push si
+ call writestr
+ call crlf
+ pop si
+ call tftp_connect
+ jnz .success
+
.badness: popa
dec di
loop .tryagain
is_486:
;
-; Initialization that does not need to go into the any of the pre-load
-; areas
-;
- call adjust_screen
-;
; Now we're all set to start with our *real* business. First load the
; configuration file (if any) and parse it.
;
.norge: jmp short .norge ; If int 19h returned; this is the end
;
-; searchdir: Search the root directory for a pre-mangled filename in
-; DS:DI. This routine is similar to the one in the boot
-; sector, but is a little less Draconian when it comes to
-; error handling, plus it reads the root directory in
-; larger chunks than a sector at a time (which is probably
-; a waste of coding effort, but I like to do things right).
+; tftp_connect:
;
-; FIXME: usually we can load the entire root dir in memory,
-; and files are usually at the beginning anyway. It probably
-; would be worthwhile to remember if we have the first chunk
-; in memory and skip the load if that (it would speed up online
-; help, mainly.)
-;
-; NOTE: This file considers finding a zero-length file an
-; error. This is so we don't have to deal with that special
-; case elsewhere in the program (most loops have the test
-; at the end).
+; Open a TFTP connection to the server
;
+; On entry:
+; DS:SI = filename
; If successful:
; ZF clear
-; SI = cluster # for the first cluster
-; DX:AX = file length in bytes
+; SI = socket pointer
+; DX:AX = file length in bytes [OBSOLETE]
; If unsuccessful
; ZF set
;
-searchdir:
- ; No longer applicable
-dir_return:
+searchdir: ; Old name for this function [OBSOLETE]
+tftp_connect:
+ push bp
+ mov bp,sp
+
+ call dot
+
+ call allocate_socket
+ jz near .error
+
+ call dot
+
+ mov ax,PKT_RETRY ; Retry counter
+
+.sendreq: push ax ; [bp-2] - Retry counter
+ push si ; [bp-4] - File name
+ push bx ; [bp-6] - TFTP block
+ mov bx,[bx]
+ push bx ; [bp-8] - TID (socket port no)
+
+ mov eax,[ServerIP] ; Server IP
+ mov [pxe_udp_write_pkt.sip],eax
+ mov [pxe_udp_write_pkt.lport],bx
+ mov ax,[ServerPort]
+ mov [pxe_udp_write_pkt.rport],ax
+ mov di,packet_buf
+ mov [pxe_udp_write_pkt.buffer],di
+ mov ax,TFTP_RRQ ; TFTP opcode
+ stosw
+ call strcpy ; Filename
+ mov si,octet_str
+ call strcpy
+ sub di,packet_buf ; Get packet size
+ mov [pxe_udp_write_pkt.buffersize],di
+
+ mov al,'S'
+ call writechr
+
+ mov di,pxe_udp_write_pkt
+ mov bx,0033h ; PXENV_UDP_WRITE
+ call far [PXENVEntry]
+ jc near .failure
+ cmp word [pxe_udp_write_pkt.status],byte 0
+ jne near .failure
+
+ ;
+ ; Danger, Will Robinson! We need to support timeout
+ ; and retry lest we just lost a packet...
+ ;
+
+ ; Packet transmitted OK, now we need to receive
+.getpacket: push word PKT_TIMEOUT ; [bp-10]
+
+ xor ax,ax
+ int 1Ah
+ push dx ; [bp-12]
+
+.pkt_loop: mov bx,[bp-8] ; TID
+ mov di,packet_buf
+ mov [pxe_udp_read_pkt.buffer],di
+ mov di,packet_buf_size
+ mov [pxe_udp_read_pkt.buffersize],di
+ mov eax,[bootp.yip] ; Our own IP
+ mov [bx+tftp_localip],eax
+ mov [pxe_udp_read_pkt.dip],eax
+ mov [pxe_udp_read_pkt.lport],bx
+ mov di,pxe_udp_read_pkt
+ mov bx,0032h ; PXENV_UDP_READ
+ call far [PXENVEntry]
+ and ax,ax
+ jz .got_packet ; Wait for packet
+.no_packet:
+ xor ax,ax
+ int 1Ah
+ cmp dx,[bp-12]
+ je .pkt_loop
+ mov [bp-12],dx
+ dec word [bp-10] ; Timeout
+ jnz .pkt_loop
+ pop ax ; Adjust stack
+ pop ax
+ jmp short .failure
+
+.got_packet:
+ mov al,'R'
+ call writechr
+
+ mov bx,[bp-8] ; TID
+
+ mov eax,[ServerIP]
+ cmp [pxe_udp_read_pkt.sip],eax
+ jne .no_packet
+ mov [bx+tftp_remoteip],eax
+
+ pop ax ; Adjust stack
+ pop ax
+
+ mov ax,[pxe_udp_read_pkt.rport]
+ mov [bx+tftp_remoteport],ax
+
+ movzx eax,word [pxe_udp_read_pkt.buffersize]
+ sub eax, byte 4
+ jb .failure ; Garbled reply
+ mov [bx+tftp_filepos], eax
+
+ cmp word [packet_buf], TFTP_ERROR
+ je .bailnow ; ERROR reply: don't try again
+
+ cmp word [packet_buf], TFTP_DATA
+ jne .failure ; Non-DATA reply -> error
+
+ cmp word [packet_buf+2], htons(1)
+ jne .failure ; Packet # != 1
+
+ ; Now we have a packet of data which we don't know what
+ ; to do with. Need to save this somewhere...
+
+.ackpacket: mov word [packet_buf], TFTP_ACK
+ mov [pxe_udp_write_pkt.buffersize], word 4
+
+ mov al,'A'
+ call writechr
+
+ mov di,pxe_udp_write_pkt
+ mov bx,0033h ; PXENV_UDP_WRITE
+ call far [PXENVEntry]
+ jc .failure
+ cmp word [pxe_udp_write_pkt.status],byte 0
+ jne .failure
+
+ ; Success, done!
+ pop si ; Junk
+ pop si ; We want the packet ptr in SI
+ pop bp ; Junk
+ pop bp ; Junk (retry counter)
+ and bp,bp ; BP != 0, ZF <- 0
+ pop bp
+ ret
+
+.bailnow: mov al,'B'
+ call writechr
+ add sp,byte 8 ; Immediate error - no retry
+ jmp short .error
+
+.failure: mov al,'F'
+ call writechr
+ pop bx ; Junk
+ pop bx
+ pop si
+ pop ax
+ dec ax ; Retry counter
+ jnz near .sendreq ; Try again
+
+.error: xor si,si ; ZF <- 1
+ pop bp
+ ret
+
+;
+; allocate_socket: Allocate a local UDP port structure
+;
+; If successful:
+; ZF set
+; BX = socket pointer
+; If unsuccessful:
+; ZF clear
+;
+allocate_socket:
+ push cx
+ mov bx,Sockets
+ mov cx,MAX_SOCKETS
+.check: cmp word [bx], byte 0
+ je .found
+ add bx,tftp_port_t_size
+ loop .check
+ xor cx,cx ; ZF = 1
+ pop cx
+ ret
+.found: mov cx,[MySocket]
+ inc cx
+ and cx,0BFFFh ; Wrap 32768->49151 (ZF = 0)
+ mov [MySocket],cx
+ xchg ch,cl ; Convert to network byte order
+ mov [bx],cx ; Socket in use
+ pop cx
+ ret
+
+;
+; strcpy: Copy DS:SI -> ES:DI up to and including a null byte
+;
+strcpy: push ax
+.loop: lodsb
+ stosb
+ and al,al
+ jnz .loop
+ pop ax
ret
;
cmc ; Set CF unless ax == 0
retf
+;
+; Debugging routine: print packet data
+;
+debug_pxenv:
+ push ax
+ push bx
+ mov al,'['
+ call writechr
+ mov ax,bx
+ call writehex4
+ mov al,':'
+ call writechr
+ pop bx
+ pop ax
+ push di
+ call far [PXENVEntry]
+ pop di
+ pushf
+ push ax
+ mov ax,[di]
+ call writehex4
+ mov al,']'
+ call writechr
+ pop ax
+ popf
+ ret
+
+;
+; dot: debugging routine, prints a dot w/o clobbering registers
+;
+dot: pushad
+ pushfd
+ mov al,'.'
+ call writechr
+ popfd
+ popad
+ ret
+
; ----------------------------------------------------------------------------------
; Begin data section
; ----------------------------------------------------------------------------------
bailmsg equ err_bootfailed
err_nopxe db 'Cannot find !PXE structure, I want my mommy!' ,0Dh, 0Ah, 0
err_pxefailed db 'PXE API call failed, error ', 0
+err_udpinit db 'Failed to initialize UDP stack', 0Dh, 0Ah, 0
found_pxenv db 'Found PXENV+ structure', 0Dh, 0Ah, 0
-using_pxenv_msg db 'PXE API 2.0 detected, using PXENV+ structure', 0Dh, 0Ah, 0
+using_pxenv_msg db 'Old PXE API detected, using PXENV+ structure', 0Dh, 0Ah, 0
apiver_str db 'PXE API version is ',0
pxeentry_msg db 'PXE entry point found (we hope) at ', 0
myipaddr_msg db 'My IP address seems to be ',0
+trying_msg db 'Trying to load: ', 0
loading_msg db 'Loading ', 0
dotdot_msg db '.'
dot_msg db '.', 0
default_str db 'default', 0
default_len equ ($-default_str)
pxelinux_banner db 0Dh, 0Ah, 'PXELINUX ', version_str, ' ', date, ' ', 0
+dot_cfg_slash db '.cfg/' ; No final null!
+dot_cfg_slash_len equ ($-dot_cfg_slash)
;
; Command line options we'd like to take a look at
.buffer: dw bootp, 0 ; seg:off of buffer
.bufferlimit: dw 0 ; Unused
+pxe_udp_open_pkt:
+.status: dw 0 ; Status
+.sip: dd 0 ; Source (our) IP
+
+pxe_udp_close_pkt:
+.status: dw 0 ; Status
+
+pxe_udp_write_pkt:
+.status: dw 0 ; Status
+.sip: dd 0 ; Server IP
+.gip: dd 0 ; Gateway IP
+.lport: dw 0 ; Local port
+.rport: dw 0 ; Remote port
+.buffersize: dw 0 ; Size of packet
+.buffer: dw 0, 0 ; seg:off of buffer
+
+pxe_udp_read_pkt:
+.status: dw 0 ; Status
+.sip: dd 0 ; Source IP
+.dip: dd 0 ; Destination (our) IP
+.rport: dw 0 ; Remote port
+.lport: dw 0 ; Local port
+.buffersize: dw 0 ; Max packet size
+.buffer: dw 0, 0 ; seg:off of buffer
+
pxe_tftp_open_pkt:
.status: dw 0 ; Status
.sip: dd 0 ; Server IP
.gip: dd 0 ; Gateway IP
.filename: times 128 db 0 ; Input filename
-.tftpport: dw 69 ; TFTP port
+.tftpport: dw TFTP_PORT ; TFTP port
.packetsize: dw 1024 ; Packet size
pxe_tftp_read_pkt:
ForcePrompt dw 0 ; Force prompt
AllowImplicit dw 1 ; Allow implicit kernels
SerialPort dw 0 ; Serial port base (or 0 for no serial port)
+MySocket dw 32768 ; Local UDP socket counter
+
+;
+; TFTP commands
+;
+octet_str db 'octet', 0 ; Octet mode
+
;
; Stuff for the command line; we do some trickery here with equ to avoid
; tons of zeros appended to our file and wasting space
projects / platform / upstream / syslinux.git / commitdiff