Support non-mkisofs mastering programs

diff --git a/Makefile b/Makefile
index f77f259..463d1f7 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,7 @@
-## -----------------------------------------------------------------------
 ##  $Id$
+## -----------------------------------------------------------------------
 ##
-##   Copyright 1998-2003 H. Peter Anvin - All Rights Reserved
+##   Copyright 1998-2004 H. Peter Anvin - All Rights Reserved
 ##
 ##   This program is free software; you can redistribute it and/or modify
 ##   it under the terms of the GNU General Public License as published by
@@ -49,7 +49,7 @@ LIB_SO  = libsyslinux.so.$(VERSION)
 #
 CSRC    = syslinux.c syslinux-nomtools.c syslxmod.c gethostip.c
 NASMSRC  = ldlinux.asm syslinux.asm copybs.asm \
-         pxelinux.asm mbr.asm isolinux.asm isolinux-debug.asm
+         pxelinux.asm mbr.asm isolinux.asm
 SOURCES = $(CSRC) *.h $(NASMSRC) *.inc
 # syslinux.exe is BTARGET so as to not require everyone to have the
 # mingw suite installed
@@ -115,17 +115,20 @@ pxelinux.bin: pxelinux.asm kwdhash.gen version.gen
        $(NASM) -f bin -DDATE_STR="'$(DATE)'" -DHEXDATE="$(HEXDATE)" \
                -l pxelinux.lst -o pxelinux.bin pxelinux.asm
 
-isolinux.bin: isolinux.asm kwdhash.gen version.gen
+isolinux.bin: isolinux.asm kwdhash.gen version.gen checksumiso.pl
        $(NASM) -f bin -DDATE_STR="'$(DATE)'" -DHEXDATE="$(HEXDATE)" \
                -l isolinux.lst -o isolinux.bin isolinux.asm
+       $(PERL) checksumiso.pl isolinux.bin
 
 pxelinux.0: pxelinux.bin
        cp pxelinux.bin pxelinux.0
 
 # Special verbose version of isolinux.bin
-isolinux-debug.bin: isolinux-debug.asm kwdhash.gen
+isolinux-debug.bin: isolinux.asm kwdhash.gen version.gen checksumiso.pl
        $(NASM) -f bin -DDATE_STR="'$(DATE)'" -DHEXDATE="$(HEXDATE)" \
-               -l isolinux-debug.lst -o isolinux-debug.bin isolinux-debug.asm
+               -DDEBUG_MESSAGES \
+               -l isolinux-debug.lst -o isolinux-debug.bin isolinux.asm
+       $(PERL) checksumiso.pl $@
 
 ldlinux.bss: ldlinux.bin
        dd if=ldlinux.bin of=ldlinux.bss bs=512 count=1

diff --git a/NEWS b/NEWS
index a3a0849..82c24c8 100644 (file)
--- a/NEWS
+++ b/NEWS
@@ -11,6 +11,9 @@ Changes in 2.12:
          not use the linker for the 16-bit code.
        * SYSLINUX: If we're building on a machine without a Win32
          (mingw) compiler, just skip building syslinux.exe.
+       * ISOLINUX: Support non-mkisofs mastering programs, at least
+         as long as the image is single-session.  For best results,
+         ISOLINUX should be the only boot loader installed.
 
 Changes in 2.11:
        * ALL: Add an API call to get the configuration file name.

diff --git a/checksumiso.pl b/checksumiso.pl
new file mode 100755 (executable)
index 0000000..b552742
--- /dev/null
+++ b/checksumiso.pl
@@ -0,0 +1,36 @@
+#!/usr/bin/perl
+#
+# Construct a checksum for isolinux*.bin, compatible
+# with an mkisofs boot-info-table
+#
+
+use bytes;
+use integer;
+
+($file) = @ARGV;
+
+open(FILE, '+<', $file) or die "$0: Cannot open $file: $!\n";
+binmode FILE;
+
+if ( !seek(FILE,64,0) ) {
+    die "$0: Cannot seek past header\n";
+}
+
+$csum  = 0;
+$bytes = 64;
+while ( ($n = read(FILE, $dw, 4)) > 0 ) {
+    $dw .= "\0\0\0\0";         # Pad to at least 32 bits
+    ($v) = unpack("V", $dw);
+    $csum  = ($csum + $v) & 0xffffffff;
+    $bytes += $n;
+}
+
+if ( !seek(FILE,16,0) ) {
+    die "$0: Cannot seek to header\n";
+}
+
+print FILE pack("VV", $bytes, $csum);
+
+close(FILE);
+
+exit 0;

diff --git a/isolinux-debug.asm b/isolinux-debug.asm
deleted file mode 100644 (file)
index be3b6ce..0000000
--- a/isolinux-debug.asm
+++ /dev/null
@@ -1,21 +0,0 @@
-;; $Id$
-;; -----------------------------------------------------------------------
-;;   
-;;   Copyright 2002 H. Peter Anvin - All Rights Reserved
-;;
-;;   This program is free software; you can redistribute it and/or modify
-;;   it under the terms of the GNU General Public License as published by
-;;   the Free Software Foundation, Inc., 53 Temple Place Ste 330,
-;;   Bostom MA 02111-1307, USA; either version 2 of the License, or
-;;   (at your option) any later version; incorporated herein by reference.
-;;
-;; -----------------------------------------------------------------------
-
-;;
-;; isolinux-debug.asm
-;;
-;; Wrapper for debugging version of ISOLINUX
-;;
-
-%define DEBUG_MESSAGES
-%include "isolinux.asm"

diff --git a/isolinux.asm b/isolinux.asm
index 150f9cb..4da7f1b 100644 (file)
--- a/isolinux.asm
+++ b/isolinux.asm
@@ -240,10 +240,12 @@ _start:           ; Far jump makes sure we canonicalize the address
                jmp 0:_start1
                times 8-($-$$) nop              ; Pad to file offset 8
 
-               ; This table gets filled in by mkisofs using the
-               ; -boot-info-table option
-bi_pvd:                dd 0xdeadbeef                   ; LBA of primary volume descriptor
-bi_file:       dd 0xdeadbeef                   ; LBA of boot file
+               ; This table hopefully gets filled in by mkisofs using the
+               ; -boot-info-table option.  If not, the values in this
+               ; table are default values that we can use to get us what
+               ; we need, at least under a certain set of assumptions.
+bi_pvd:                dd 16                           ; LBA of primary volume descriptor
+bi_file:       dd 0                            ; LBA of boot file
 bi_length:     dd 0xdeadbeef                   ; Length of boot file
 bi_csum:       dd 0xdeadbeef                   ; Checksum of boot file
 bi_reserved:   times 10 dd 0xdeadbeef          ; Reserved
@@ -280,15 +282,6 @@ initial_csum:      xor edi,edi
                loop .loop
                mov [FirstSecSum],edi
 
-               ; Set up boot file sizes
-               mov eax,[bi_length]
-               sub eax,SECTORSIZE-3
-               shr eax,2                       ; bytes->dwords
-               mov [ImageDwords],eax           ; boot file dwords
-               add eax,(2047 >> 2)
-               shr eax,9                       ; dwords->sectors
-               mov [ImageSectors],ax           ; boot file sectors
-
                mov [DriveNo],dl
 %ifdef DEBUG_MESSAGES
                mov si,startup_msg
@@ -319,11 +312,63 @@ initial_csum:     xor edi,edi
 %endif
 
 found_drive:
+               ; Alright, we have found the drive.  Now, try to find the
+               ; boot file itself.  If we have a boot info table, life is
+               ; good; if not, we have to make some assumptions, and try
+               ; to figure things out ourselves.  In particular, the
+               ; assumptions we have to make are:
+               ; - single session only
+               ; - only one boot entry (no menu or other alternatives)
+
+               cmp dword [bi_file],0           ; Address of code to load
+               jne found_file                  ; Boot info table present :)
+
+;%ifdef DEBUG_MESSAGES
+               mov si,noinfotable_msg
+               call writemsg
+;%endif
+               
+               ; No such luck.  See if the the spec packet contained one.
+               mov eax,[sp_lba]
+               and eax,eax
+               jz set_file                     ; Good enough
+
+;%ifdef DEBUG_MESSAGES
+               mov si,noinfoinspec_msg
+               call writemsg
+;%endif
+               
+               ; No such luck.  Get the Boot Record Volume, assuming single
+               ; session disk, and that we're the first entry in the chain
+               mov eax,17                      ; Assumed address of BRV
+               mov bx,trackbuf
+               call getonesec
+
+               mov eax,[trackbuf+47h]          ; Get boot catalog address
+               mov bx,trackbuf
+               call getonesec                  ; Get boot catalog
+
+               mov eax,[trackbuf+28h]          ; First boot entry
+               ; And hope and pray this is us...
+
                ; Some BIOSes apparently have limitations on the size 
                ; that may be loaded (despite the El Torito spec being very
                ; clear on the fact that it must all be loaded.)  Therefore,
                ; we load it ourselves, and *bleep* the BIOS.
 
+set_file:
+               mov [bi_file],eax
+
+found_file:
+               ; Set up boot file sizes
+               mov eax,[bi_length]
+               sub eax,SECTORSIZE-3
+               shr eax,2                       ; bytes->dwords
+               mov [ImageDwords],eax           ; boot file dwords
+               add eax,(2047 >> 2)
+               shr eax,9                       ; dwords->sectors
+               mov [ImageSectors],ax           ; boot file sectors
+
                mov eax,[bi_file]               ; Address of code to load
                inc eax                         ; Don't reload bootstrap code
 %ifdef DEBUG_MESSAGES
@@ -749,6 +794,8 @@ loaded_msg: db 'Loaded boot image, verifying...', CR, LF, 0
 verify_msg:    db 'Image checksum verified.', CR, LF, 0
 allread_msg    db 'Main image read, jumping to main code...', CR, LF, 0
 %endif
+noinfotable_msg        db 'No boot info table, assuming single session disk...', CR, LF, 0
+noinfoinspec_msg db 'Spec packet missing LBA information, trying to wing it...', CR, LF, 0
 spec_err_msg:  db 'Loading spec packet failed, trying to wing it...', CR, LF, 0
 maybe_msg:     db 'Found something at drive = ', 0
 alright_msg:   db 'Looks like it might be right, continuing...', CR, LF, 0
@@ -782,22 +829,6 @@ sp_chs:            db 0,0,0                        ; Simulated CHS geometry
 sp_dummy:      db 0                            ; Scratch, safe to overwrite
 
 ;
-; Spec packet for disk image emulation
-;
-               align 8, db 0
-dspec_packet:  db 13h                          ; Size of packet
-dsp_media:     db 0                            ; Media type
-dsp_drive:     db 0                            ; Drive number
-dsp_controller:        db 0                            ; Controller index
-dsp_lba:       dd 0                            ; LBA for emulated disk image
-dsp_devspec:   dw 0                            ; IDE/SCSI information
-dsp_buffer:    dw 0                            ; User-provided buffer
-dsp_loadseg:   dw 0                            ; Load segment
-dsp_sectors:   dw 1                            ; Sector count
-dsp_chs:       db 0,0,0                        ; Simulated CHS geometry
-dsp_dummy:     db 0                            ; Scratch, safe to overwrite
-
-;
 ; EBIOS drive parameter packet
 ;
                align 8, db 0
@@ -1667,6 +1698,7 @@ img_table:
 ;
 ; Misc initialized (data) variables
 ;
+               align 4, db 0
 AppendLen       dw 0                    ; Bytes in append= command
 OntimeoutLen   dw 0                    ; Bytes in ontimeout command
 OnerrorLen     dw 0                    ; Bytes in onerror command
@@ -1684,6 +1716,22 @@ UserFont db 0                    ; Using a user-specified font
 ScrollAttribute        db 07h                  ; White on black (for text mode)
 
 ;
+; Spec packet for disk image emulation
+;
+               align 8, db 0
+dspec_packet:  db 13h                          ; Size of packet
+dsp_media:     db 0                            ; Media type
+dsp_drive:     db 0                            ; Drive number
+dsp_controller:        db 0                            ; Controller index
+dsp_lba:       dd 0                            ; LBA for emulated disk image
+dsp_devspec:   dw 0                            ; IDE/SCSI information
+dsp_buffer:    dw 0                            ; User-provided buffer
+dsp_loadseg:   dw 0                            ; Load segment
+dsp_sectors:   dw 1                            ; Sector count
+dsp_chs:       db 0,0,0                        ; Simulated CHS geometry
+dsp_dummy:     db 0                            ; Scratch, safe to overwrite
+
+;
 ; Variables that are uninitialized in SYSLINUX but initialized here
 ;
 ; **** ISOLINUX:: We may have to make this flexible, based on what the