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authorhpa <hpa>1999-09-06 11:35:04 +0000
committerhpa <hpa>1999-09-06 11:35:04 +0000
commit8171228f323d14bde4e633a90dd173c358c9d9d7 (patch)
tree9a3d41723de33d688026f8715be2451082169e7f /pxelinux.asm
parent830548566cfd6c922a64c9a98b1e7e14a09cdfe9 (diff)
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Okay, we have established communications with PXE... and are capable of
scanning for our config file. A good place to stop.
Diffstat (limited to 'pxelinux.asm')
-rw-r--r--pxelinux.asm568
1 files changed, 295 insertions, 273 deletions
diff --git a/pxelinux.asm b/pxelinux.asm
index 6a6dd903..cdd5c2c1 100644
--- a/pxelinux.asm
+++ b/pxelinux.asm
@@ -243,6 +243,7 @@ HiLoadAddr resd 1 ; Address pointer for high load loop
HighMemSize resd 1 ; End of memory pointer (bytes)
KernelSize resd 1 ; Size of kernel (bytes)
Stack resd 1 ; Pointer to reset stack
+PXEEntry resd 1 ; !PXE API entry point
RootDir equ $ ; Location of root directory
RootDir1 resw 1
RootDir2 resw 1
@@ -296,6 +297,30 @@ InitRDCName resb MAX_FILENAME ; Unmangled initrd name
MNameBuf resb 11 ; OBSOLETE
InitRD resb 11 ; OBSOLETE
+ alignb 16
+ ; BOOTP/DHCP packet buffer
+bootp:
+.opcode resb 1 ; BOOTP/DHCP "opcode"
+.hardware resb 1 ; ARP hardware type
+.hardlen resb 1 ; Hardware address length
+.gatehops resb 1 ; Used by forwarders
+.ident resd 1 ; Transaction ID
+.seconds resw 1 ; Seconds elapsed
+.flags resw 1 ; Broadcast flags
+.cip resd 1 ; Client IP
+.yip resd 1 ; "Your" IP
+.sip resd 1 ; Next server IP
+.gip resd 1 ; Relay agent IP
+.macaddr resb 16 ; Client MAC address
+.sname resb 64 ; Server name (optional)
+.bootfile resb 128 ; Boot file name
+.v_magic resd 1 ; DHCP magic cookie
+.v_flags resd 1 ; DHCP flags
+.v_pad resb 56 ; Vendor options padding
+
+bootp_size equ $-bootp
+
+
section .text
org 7C00h
;
@@ -332,17 +357,24 @@ _start1:
cmp ax,564Eh
jne no_pxe
- mov si,found_pxenv
- call writestr
-
; Okay, that gave us the PXENV+ structure, find !PXE
; structure from that
cmp dword [es:bx], 'PXEN'
jne no_pxe
cmp word [es:bx+4], 'V+'
jne no_pxe
+
+ mov si,found_pxenv
+ call writestr
+
+ mov si,apiver_str
+ call writestr
+ mov ax,[es:bx+6]
+ call writehex4
+ call crlf
+
cmp word [es:bx+6], 0201h ; API version 2.1 or higher
- jb no_pxe
+ jb old_api
les bx,[es:bx+26h] ; !PXE structure pointer
cmp dword [es:bx],'!PXE'
je have_pxe
@@ -351,7 +383,26 @@ no_pxe: mov si,err_nopxe
call writestr
jmp kaboom
+old_api: ; Need to use a PXENV+ structure
+ mov si,using_pxenv_msg
+ call writestr
+
+ mov eax,[es:bx+0Ah] ; PXE RM API
+ mov [PXENVEntry],eax
+ jmp short have_pxe_entry
have_pxe:
+ mov eax,[es:bx+10h]
+ mov [PXEEntry],eax
+
+have_pxe_entry: mov si,pxeentry_msg
+ call writestr
+ mov ax,[PXENVEntry+2]
+ call writehex4
+ mov al,':'
+ call writechr
+ mov ax,[PXENVEntry]
+ call writehex4
+ call crlf
;
; Tell the user we got this far
@@ -359,174 +410,148 @@ have_pxe:
mov si,pxelinux_banner
call writestr
-.enough: jmp short .enough
-
+ mov si,copyright_str
+ call writestr
+
;
-; -----------------------------------------------------------------------------
-; Subroutines that have to be in the first sector
-; -----------------------------------------------------------------------------
+; Now attempt to get the BOOTP/DHCP packet that brought us life (and an IP
+; address)
;
-; getfssec: Get multiple clusters from a file, given the starting cluster.
+query_bootp: mov ax,0DEADh ; Something bogus
+
+ mov ax,ds
+ mov es,ax
+ mov di,pxe_bootp_query_pkt
+ mov bx,0071h ; PXENV_GET_CACHED_INFO
+
+ call far [PXENVEntry]
+ jc .pxe_err
+ cmp ax,byte 0
+ je .pxe_ok
+.pxe_err:
+ mov si,err_pxefailed
+ call writestr
+ call writehex4
+ call crlf
+
+.pxe_ok: mov si,myipaddr_msg
+ call writestr
+ mov eax,[bootp.yip] ; "Your" IP address
+ call writehex8
+ mov al,' '
+ call writechr
+ mov eax,[bootp.sip] ; Server IP address(?)
+ call writehex8
+ mov al,' '
+ call writechr
+ mov eax,[bootp.gip] ; Gateway IP address(?)
+ call writehex8
+ call crlf
+
+ ; Print the boot file
+ mov si,bootp.bootfile
+ call writestr
+ call crlf
;
-; This routine makes sure the subtransfers do not cross a 64K boundary,
-; and will correct the situation if it does, UNLESS *sectors* cross
-; 64K boundaries.
+; Normalize ES = DS
;
-; ES:BX -> Buffer
-; SI -> Starting cluster number (2-based)
-; CX -> Cluster count (0FFFFh = until end of file)
+ mov ax,ds
+ mov es,ax
;
- ; 386 check
-getfssec:
-%if 0
-getfragment: xor bp,bp ; Fragment sector count
- mov ax,si ; Get sector address
- dec ax ; Convert to 0-based
- dec ax
- mul word [SecPerClust]
- add ax,[DataArea1]
- adc dx,[DataArea2]
-getseccnt: ; See if we can read > 1 clust
- add bp,[SecPerClust]
- dec cx ; Reduce clusters left to find
- mov di,si ; Predict next cluster
+; Now, prepare some of the data structures
+;
+ mov eax,[bootp.sip]
+ mov [pxe_tftp_open_pkt.sip],eax
+
+filename_cp: mov si,bootp.bootfile
+ mov di,pxe_tftp_open_pkt.filename
+ cld
+ xor cx,cx
+.strcpy: lodsb
+ stosb
+ inc cx
+ and al,al
+ jnz .strcpy
+ std
+ dec di
+ mov si,di
+ mov al,'.'
+ repne scasb
+ jne .nodot
inc di
- call [NextCluster]
- jc gfs_eof ; At EOF?
- jcxz endfragment ; Or was it the last we wanted?
- cmp si,di ; Is file continuous?
- jz getseccnt ; Yes, we can get
-endfragment: clc ; Not at EOF
-gfs_eof: pushf ; Remember EOF or not
- push si
- push cx
-gfs_getchunk:
- push ax
- push dx
- mov ax,es ; Check for 64K boundaries.
- mov cl,4
- shl ax,cl
- add ax,bx
- xor dx,dx
- neg ax
- jnz gfs_partseg
- inc dx ; Full 64K segment
-gfs_partseg:
- div word [bsBytesPerSec] ; How many sectors fit?
- mov si,bp
- sub si,ax ; Compute remaining sectors
- jbe gfs_lastchunk
- mov bp,ax
- pop dx
- pop ax
- call getlinsecsr
- add ax,bp
- adc dx,byte 0
- mov bp,si ; Remaining sector count
- jmp short gfs_getchunk
-gfs_lastchunk: pop dx
- pop ax
- call getlinsec
- pop cx
- pop si
- popf
- jcxz gfs_return ; If we hit the count limit
- jnc getfragment ; If we didn't hit EOF
-gfs_return: ret
+ jmp short .dot
+.nodot: mov di,si
+.dot: cld
+ ; Now di points to where we want to add stuff to the filename
+ mov al,'/'
+ stosb
+ mov cx,8
+ mov eax,[bootp.yip]
+ bswap eax ; Convert to native byte order
+.hexify_loop: rol eax,4
+ push eax
+ and al,0Fh
+ cmp al,10
+ jae .high
+.low: add al,'0'
+ jmp short .char
+.high: add al,'A'-10
+.char: stosb
+ pop eax
+ loop .hexify_loop
;
-; getlinsecsr: save registers, call getlinsec, restore registers
+; Begin looking for configuration file
;
-getlinsecsr: push ax
- push dx
- push cx
- push bp
- push si
- push di
- call getlinsec
- pop di
- pop si
- pop bp
- pop cx
- pop dx
- pop ax
- ret
-%endif
+config_scan:
+ mov cx,9 ; Up to 9 attempts
-;
-; nextcluster: Advance a cluster pointer in SI to the next cluster
-; pointed at in the FAT tables (note: FAT12 assumed)
-; Sets CF on return if end of file.
-;
-; The variable NextCluster gets set to the appropriate
-; value here.
-;
-nextcluster_fat12:
- push ax
- push ds
- mov ax,fat_seg
- mov ds,ax
- mov ax,si ; Multiply by 3/2
- shr ax,1
- pushf ; CF now set if odd
- add si,ax
- mov si,[si]
- popf
- jnc nc_even
- shr si,1 ; Needed for odd only
- shr si,1
- shr si,1
- shr si,1
-nc_even:
- and si,0FFFh
- cmp si,0FF0h ; Clears CF if at end of file
- cmc ; But we want it SET...
- pop ds
- pop ax
-nc_return: ret
+.tryagain: mov byte [di],0
+ cmp cx,byte 1
+ jne .not_default
+ pusha
+ mov si,default_str
+ mov cx,default_len
+ 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
+.badness: popa
+ dec di
+ loop .tryagain
;
-; FAT16 decoding routine. Note that a 16-bit FAT can be up to 128K,
-; so we have to decide if we're in the "low" or the "high" 64K-segment...
-;
-nextcluster_fat16:
- push ax
- push ds
- mov ax,fat_seg
- shl si,1
- jnc .seg0
- mov ax,fat_seg+1000h
-.seg0: mov ds,ax
- mov si,[si]
- cmp si,0FFF0h
- cmc
- pop ds
- pop ax
- ret
-;
-; Debug routine
+; If we get here, no configuration file
;
-%ifdef debug
-safedumpregs:
- cmp word [Debug_Magic],0D00Dh
- jnz nc_return
- jmp dumpregs
-%endif
-rl_checkpt equ $ ; Must be <= 400h
+.success: popa
+ ; If we get here, we have an open TFTP connection to the config file
-; ----------------------------------------------------------------------------
-; End of code and data that have to be in the first sector
-; ----------------------------------------------------------------------------
+enough: mov si,enough_msg
+ call writestr
+ jmp kaboom
+enough_msg: db 13,10,10,'End of implemented code.', 13, 10, 0
-all_read:
;
-; Let the user (and programmer!) know we got this far. This used to be
-; in Sector 1, but makes a lot more sense here.
+; getfssec: Get multiple clusters from a file, given the starting cluster.
;
- mov si,copyright_str
- call writestr
+; This routine makes sure the subtransfers do not cross a 64K boundary,
+; and will correct the situation if it does, UNLESS *sectors* cross
+; 64K boundaries.
;
+; ES:BX -> Buffer
+; SI -> Starting cluster number (2-based)
+; CX -> Cluster count (0FFFFh = until end of file)
+;
+ ; 386 check
+;
; Check that no moron is trying to boot Linux on a 286 or so. According
; to Intel, the way to check is to see if the high 4 bits of the FLAGS
; register are either all stuck at 1 (8086/8088) or all stuck at 0
@@ -611,13 +636,6 @@ is_486:
;
call adjust_screen
;
-; Now, everything is "up and running"... patch kaboom for more
-; verbosity and using the full screen system
-;
- mov byte [kaboom.patch],0e9h ; JMP NEAR
- mov word [kaboom.patch+1],kaboom2-(kaboom.patch+3)
-
-;
; Now we're all set to start with our *real* business. First load the
; configuration file (if any) and parse it.
;
@@ -945,7 +963,7 @@ enter_char: test byte [FuncFlag],1
get_char_2: jmp short get_char
not_ascii: mov byte [FuncFlag],0
cmp al,0Dh ; Enter
- je command_done
+ je near command_done
cmp al,06h ; <Ctrl-F>
je set_func_flag
cmp al,08h ; Backspace
@@ -1241,7 +1259,7 @@ kernel_sane: push ax
sub [KernelClust],cx
xor bx,bx
pop si ; Cluster pointer on stack
- call getfssec
+; call getfssec
jc near kernel_corrupt ; Failure in first 32K
cmp word [es:bs_bootsign],0AA55h
jne near kernel_corrupt ; Boot sec signature missing
@@ -1486,7 +1504,7 @@ high_last_moby:
sub [KernelClust],cx
xor bx,bx ; Load at offset 0
pop si ; Restore cluster pointer
- call getfssec
+; call getfssec
push si ; Save cluster pointer
pushf ; Save EOF
xor bx,bx
@@ -1625,7 +1643,7 @@ is_comboot_image:
mov bx,100h ; Load at <seg>:0100h
mov cx,[ClustPerMoby] ; Absolute maximum # of clusters
- call getfssec
+; call getfssec
xor di,di
mov cx,64 ; 256 bytes (size of PSP)
@@ -1935,7 +1953,7 @@ rd_last_moby:
push word xfer_buf_seg ; Bounce buffer segment
pop es
push cx
- call getfssec
+; call getfssec
pop cx
push si ; Save cluster pointer
mov esi,(xfer_buf_seg << 4)
@@ -2009,20 +2027,6 @@ kaboom:
.norge: jmp short .norge ; If int 19h returned; this is the end
;
-;
-; writestr: write a null-terminated string to the console
-;
-writestr:
-wstr_1: lodsb
- and al,al
- jz .return
- mov ah,0Eh ; Write to screen as TTY
- mov bx,0007h ; White on black, current page
- int 10h
- jmp short wstr_1
-.return: ret
-
-;
; 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
@@ -2080,7 +2084,7 @@ bf_ret: ret
loadfont:
mov bx,trackbuf ; The trackbuf is >= 16K; the part
mov cx,[BufSafe] ; of a PSF file we care about is no
- call getfssec ; more than 8K+4 bytes
+; call getfssec ; more than 8K+4 bytes
mov ax,[trackbuf] ; Magic number
cmp ax,0436h
@@ -2120,7 +2124,7 @@ loadkeys:
mov bx,trackbuf
mov cx,1 ; 1 cluster should be >= 256 bytes
- call getfssec
+; call getfssec
mov si,trackbuf
mov di,KbdMap
@@ -2147,7 +2151,7 @@ get_msg_chunk: push ax ; DX:AX = length of file
push dx
mov bx,trackbuf
mov cx,[BufSafe]
- call getfssec
+; call getfssec
pop dx
pop ax
push si ; Save current cluster
@@ -2290,27 +2294,68 @@ write_serial_str:
;
writechr:
call write_serial ; write to serial port if needed
- pusha
+ pushad
mov ah,0Eh
mov bx,0007h ; white text on this page
int 10h
- popa
+ popad
ret
;
+; crlf: Print a newline
+;
+crlf: mov si,crlf_msg
+ ; Fall through
+
+;
; cwritestr: write a null-terminated string to the console, saving
; registers on entry.
;
+; Note: writestr and cwritestr are distinct in SYSLINUX, not in PXELINUX
+;
cwritestr:
- pusha
+ pushad
.top: lodsb
and al,al
jz .end
call writechr
jmp short .top
-.end: popa
+.end: popad
ret
+writestr equ cwritestr
+
+;
+; writehex[248]: Write a hex number in (AL, AX, EAX) to the console
+;
+writehex2:
+ pushad
+ rol eax,24
+ mov cx,2
+ jmp short writehex_common
+writehex4:
+ pushad
+ rol eax,16
+ mov cx,4
+ jmp short writehex_common
+writehex8:
+ pushad
+ mov cx,8
+writehex_common:
+.loop: rol eax,4
+ push eax
+ and al,0Fh
+ cmp al,10
+ jae .high
+.low: add al,'0'
+ jmp short .ischar
+.high: add al,'A'-10
+.ischar: call writechr
+ pop eax
+ loop .loop
+ popad
+ ret
+
;
; pollchar: check if we have an input character pending (ZF = 0)
;
@@ -2371,13 +2416,17 @@ kaboom2:
; similar to the C library getc routine. Only one simultaneous
; use is supported. Note: "open" trashes the trackbuf.
;
-; open: Input: mangled filename in DS:DI
+; open: Input: filename in DS:DI
; Output: ZF set on file not found or zero length
;
; getc: Output: CF set on end of file
; Character loaded in AL
;
open:
+ mov di,pxe_tftp_open_pkt
+ mov bx,0020h ; PXENV_TFTP_OPEN
+ call far [PXENVEntry]
+
call searchdir
jz open_return
pushf
@@ -2415,7 +2464,7 @@ getc_oksize: sub [FClust],cx ; Reduce remaining clusters
push es ; ES may be != DS, save old ES
push ds ; Trackbuf is in DS, not ES
pop es
- call getfssec ; Load a trackbuf full of data
+; call getfssec ; Load a trackbuf full of data
mov [FNextClust],si ; Store new next pointer
pop es ; Restore ES
pop si ; SI -> newly loaded data
@@ -2684,89 +2733,6 @@ gl_ret: pushf ; We want the last char to be space!
gl_xret: popf
ret
-
-%ifdef debug ; This code for debugging only
-;
-; dumpregs: Dumps the contents of all registers
-;
- assume ds:_text, es:NOTHING, fs:NOTHING, gs:NOTHING
-dumpregs proc near ; When calling, IP is on stack
- pushf ; Store flags
- pusha
- push ds
- push es
- push fs
- push gs
- push cs ; Set DS <- CS
- pop ds
- cld ; Clear direction flag
- mov si,offset crlf_msg
- call cwritestr
- mov bx,sp
- add bx,byte 26
- mov si,offset regnames
- mov cx,2 ; 2*7 registers to dump
-dump_line: push cx
- mov cx,7 ; 7 registers per line
-dump_reg: push cx
- mov cx,4 ; 4 characters/register name
-wr_reg_name: lodsb
- call writechr
- loop wr_reg_name
- mov ax,ss:[bx]
- dec bx
- dec bx
- call writehex
- pop cx
- loop dump_reg
- mov al,0Dh ; <CR>
- call writechr
- mov al,0Ah ; <LF>
- call writechr
- pop cx
- loop dump_line
- pop gs
- pop fs
- pop es
- pop ds
- popa ; Restore the remainder
- popf ; Restore flags
- ret
-dumpregs endp
-
-regnames db ' IP: FL: AX: CX: DX: BX: SP: BP: SI: DI: DS: ES: FS: GS:'
-
-;
-; writehex: Writes a 16-bit hexadecimal number (in AX)
-;
-writehex proc near
- push bx
- push cx
- mov cx,4 ; 4 numbers
-write_hexdig: xor bx,bx
- push cx
- mov cx,4 ; 4 bits/digit
-xfer_digit: shl ax,1
- rcl bx,1
- loop xfer_digit
- push ax
- mov ax,bx
- or al,'0'
- cmp al,'9'
- jna ok_digit
- add al,'A'-'0'-10
-ok_digit: call writechr
- pop ax
- pop cx
- loop write_hexdig
- pop cx
- pop bx
- ret
-writehex endp
-
-debug_magic dw 0D00Dh
-
-%endif ; debug
;
; mangle_name: Mangle a DOS filename pointed to by DS:SI into a buffer pointed
; to by ES:DI; ends on encountering any whitespace
@@ -2878,6 +2844,29 @@ lc_1: cmp al,lcase_low
lc_ret: ret
;
+; pxe_thunk
+;
+; Convert from the PXENV+ calling convention (BX, ES, DI) to the !PXE
+; calling convention (using the stack.)
+;
+; This is called as a far routine so that we can just stick it into
+; the PXENVEntry variable.
+;
+pxe_thunk: push es
+ push di
+ push bx
+ call far [PXEEntry]
+ add sp,byte 6
+ cmp ax,byte 1
+ cmc ; Set CF unless ax == 0
+ retf
+
+; ----------------------------------------------------------------------------------
+; Begin data section
+; ----------------------------------------------------------------------------------
+
+
+;
; Lower-case table for codepage 865
;
lcase_low equ 128
@@ -2926,7 +2915,12 @@ err_bootfailed db 0Dh, 0Ah, 'Boot failed: please change disks and press '
db 'a key to continue.', 0Dh, 0Ah, 0
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
found_pxenv db 'Found PXENV+ structure', 0Dh, 0Ah, 0
+using_pxenv_msg db 'PXE API 2.0 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
loading_msg db 'Loading ', 0
dotdot_msg db '.'
dot_msg db '.', 0
@@ -2934,8 +2928,9 @@ aborted_msg db ' aborted.' ; Fall through to crlf_msg!
crlf_msg db 0Dh, 0Ah, 0
crff_msg db 0Dh, 0Ch, 0
syslinux_cfg db 'SYSLINUXCFG'
+default_str db 'default', 0
+default_len equ ($-default_str)
pxelinux_banner db 0Dh, 0Ah, 'PXELINUX ', version_str, ' ', date, ' ', 0
- db 0Dh, 0Ah, 1Ah ; EOF if we "type" this in DOS
;
; Command line options we'd like to take a look at
@@ -2946,7 +2941,8 @@ initrd_cmd_len equ 7
;
; Config file keyword table
;
- align 2
+ align 2, db 0
+
keywd_table db 'ap' ; append
db 'de' ; default
db 'ti' ; timeout
@@ -2975,6 +2971,7 @@ keywd_table db 'ap' ; append
; extension, needed for error messages. The exten_table is shifted so
; the table is 1-based; this is because a "loop" cx is used as index.
;
+ align 4, db 0
exten_table:
OrigKernelExt: dd 0 ; Original extension
db 'COM',0 ; COMBOOT (same as DOS)
@@ -2983,6 +2980,31 @@ OrigKernelExt: dd 0 ; Original extension
db 'CBT',0 ; COMBOOT (specific)
exten_count equ (($-exten_table) >> 2) - 1 ; Number of alternates
+
+;
+; PXENV entry point. If we use the !PXE API, this will point to a thunk
+; function that converts to the !PXE calling convention.
+;
+PXENVEntry dw pxe_thunk,0
+
+;
+; PXE query packets partially filled in
+;
+pxe_bootp_query_pkt:
+.status: dw 0 ; Status
+.packettype: dw 2 ; DHCPACK packet
+.buffersize: dw bootp_size ; Packet size
+.buffer: dw bootp, 0 ; seg:off of buffer
+.bufferlimit: dw 0 ; Unused
+
+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
+.packetsize dw 1024 ; Packet size
+
;
; Misc initialized (data) variables
;