KbdMap resb 256 ; Keyboard map
BootFile resb 256 ; Boot file from DHCP packet
PathPrefix resb 256 ; Path prefix derived from the above
+ConfigName resb 256 ; Configuration file from DHCP option
FKeyName resb 10*FILENAME_MAX ; File names for F-key help
NumBuf resb 15 ; Buffer to load number
NumBufEnd resb 1 ; Last byte in NumBuf
inc al
loop mkkeymap
+
+;
+; Check to see if we got any PXELINUX-specific DHCP options
+;
+check_dhcp_magic:
+ test byte [DHCPMagic], 1 ; If we didn't get the magic enable...
+ jnz .got_magic
+ mov byte [DHCPMagic], 0 ; If not, kill all other options
+.got_magic:
+
+
;
; Store standard filename prefix
;
-prefix: mov si,BootFile
+prefix: test byte [DHCPMagic], 04h ; Did we get a path prefix option
+ jnz .got_prefix
+ mov si,BootFile
mov di,PathPrefix
cld
call strcpy
dec si
.notalnum: mov byte [si+2],0 ; Zero-terminate after delimiter
cld
+.got_prefix:
mov si,tftpprefix_msg
call writestr
mov si,PathPrefix
; Begin looking for configuration file
;
config_scan:
+ test byte [DHCPMagic], 02h
+ jz .no_option
+
+ ; We got a DHCP option, try it first
+ mov si,trying_msg
+ call writestr
+ mov di,ConfigName
+ mov si,di
+ call writestr
+ call crlf
+ call open
+ jnz .success
+
+.no_option: ; Have to guess config file name
+
mov cx,9 ; Up to 9 attempts
.tryagain: mov byte [di],0
jmp short .opt_done
.not_overload:
- mov dl,67 ; BOOTFILE NAME option
+ cmp dl,67 ; BOOTFILE NAME option
jne .not_bootfile
- push cx
mov di,BootFile
- mov cx,ax
- rep movsb
- mov byte [di],0 ; Null-terminate
- pop cx
- jmp short .opt_done_noskip
+ jmp short .copyoption
+
+.done:
+ ret ; This is here to make short jumps easier
.not_bootfile:
+ cmp dl,176 ; PXELINUX MAGIC option
+ jne .not_pl_magic
+ cmp al,4 ; Must have length == 4
+ jne .opt_done
+ cmp dword [si], htonl(0xF100747E) ; Magic number
+ jne .opt_done
+ or byte [DHCPMagic], byte 1 ; Found magic #
+ jmp short .opt_done
+
+.not_pl_magic:
+ cmp dl,177 ; PXELINUX CONFIGFILE option
+ jne .not_pl_config
+ mov di,ConfigName
+ or byte [DHCPMagic], byte 2 ; Got config file
+ jmp short .copyoption
+
+.not_pl_config:
+ cmp dl,178 ; PXELINUX PATHPREFIX option
+ jne .not_pl_prefix
+ mov di,PathPrefix
+ or byte [DHCPMagic], byte 4 ; Got path prefix
+ jmp short .copyoption
+
+.not_pl_prefix:
; Unknown option. Skip to the next one.
.opt_done:
add si,ax
.opt_done_noskip:
- jmp short .loop
-.done:
- ret
+ jmp .loop
+
+ ; Common code for copying an option verbatim
+.copyoption:
+ xchg cx,ax
+ rep movsb
+ xchg cx,ax ; Now ax == 0
+ stosb ; Null-terminate
+ jmp short .opt_done_noskip
;
; genipopt
A20DList dw a20d_dunno, a20d_none, a20d_bios, a20d_kbc, a20d_fast
A20Type dw A20_DUNNO ; A20 type unknown
VGAFontSize dw 16 ; Defaults to 16 byte font
+ScrollAttribute db 07h ; White on black (for text mode)
+
;
; TFTP commands
;
%error trackbufsize must be a multiple of TFTP_BLOCKSIZE
%endif
IPAppend db 0 ; Default IPAPPEND option
-ScrollAttribute db 07h ; White on black (for text mode)
+DHCPMagic db 0 ; DHCP site-specific option info
;
; Stuff for the command line; we do some trickery here with equ to avoid
As an example, for 192.0.2.91, it will try C000025B, C000025,
C00002, C0000, C000, C00, C0, C, and default, in that order.
+(See also the section on special DHCP options.)
+
It should be noted that all filename references are relative to the
directory pxelinux.0 lives in (usually /tftpboot). PXELINUX
generally requires that filenames (including any relative path) are 63
group {
# PXE-specific configuration directives...
next-server <TFTP server address>;
+ filename "/tftpboot/pxelinux.0";
# You need an entry like this for every host
# unless you're using dynamic addresses
}
}
+Note that if your particular TFTP daemon runs under chroot (tftp-hpa
+will do this if you specify the -s (secure) option; this is highly
+recommended), you almost certainly should not include the /tftpboot
+prefix in the filename statement.
+
If this does not work for your configuration, you probably should set
up a "PXE boot server" on port 4011 of your TFTP server; a free PXE
boot server is available at:
}
}
+Here, the boot file name is obtained from the PXE server.
+
If the "conventional TFTP" configuration doesn't work on your clients,
and setting up a PXE boot server is not an option, you can attempt the
following configuration. It has been known to boot some
option dhcp-class-identifier "PXEClient";
option vendor-encapsulated-options 09:0f:80:00:0c:4e:65:74:77:6f:72:6b:20:62:6f:6f:74:0a:07:00:50:72:6f:6d:70:74:06:01:02:08:03:80:00:00:47:04:80:00:00:00:ff;
next-server <TFTP server>;
+ filename "/tftpboot/pxelinux.0";
# You need an entry like this for every host
# unless you're using dynamic addresses
"conventional TFTP" configuration; Intel Boot Client 3.0 and later are
known to fall into this category.
-Note that if your particular TFTP daemon runs under chroot (tftp-hpa
-will do this if you specify the -s (secure) option; this is
-recommended), you most likely should not include the /tftpboot prefix.
+
+ ++++ SPECIAL DHCP OPTIONS ++++
+
+PXELINUX (starting with version 1.62) supports the following
+nonstandard DHCP options, which depending on your DHCP server you may
+be able to use to customize the specific behaviour of PXELINUX:
+
+Option 176 pxelinux.magic
+ - Must be set to F1:00:74:7E (241.0.116.126) for PXELINUX to
+ recognize any special DHCP options whatsoever.
+
+Option 177 pxelinux.configfile
+ - Specifies the PXELINUX configuration file name.
+
+Option 178 pxelinux.pathprefix
+ - Specifies the PXELINUX common path prefix, instead of
+ deriving it from the boot file name. This almost certainly
+ needs to end in whatever character the TFTP server OS uses
+ as a pathname separator, e.g. slash (/) for Unix.
+
+ISC dhcp 3.0 supports a rather nice syntax for specifying custom
+options; you can use the following syntax in dhcpd.conf if you are
+running this version of dhcpd:
+
+ option space pxelinux;
+ option pxelinux.magic code 176 = string;
+ option pxelinux.configfile code 177 = text;
+ option pxelinux.pathprefix code 178 = text;
+
+Then, inside your PXELINUX-booting group or class (whereever you have
+the PXELINUX-related options, such as the filename option), you can
+add, for example:
+
+ site-option-space pxelinux;
+ option pxelinux.magic f1:00:74:7e;
+ option pxelinux.configfile "configs/common";
+ option pxelinux.pathprefix "/tftpboot/pxelinux/files/";
+ filename "/tftpboot/pxelinux/pxelinux.bin";
+
+Note that the configfile is relative to the pathprefix: this will look
+for a config file called /tftpboot/pxelinux/files/configs/common on
+the TFTP server.
+
+Using ISC dhcp 3.0 you can create a lot of these strings on the fly.
+For example, to use the hexadecimal form of the hardware address as
+the configuration file name, you could do something like:
+
+ site-option-space pxelinux;
+ option pxelinux.magic f1:00:74:7e;
+ option pxelinux.configfile =
+ concat("pxelinux.cfg/", binary-to-ascii(16, 8, ":", hardware));
+ filename "/tftpboot/pxelinux.bin";
+
+If you used this from a client whose Ethernet address was
+58:FA:84:CF:55:0E, this would look for a configuration file named
+"/tftpboot/pxelinux.cfg/1:58:fa:84:cf:55:e".
++++ SOME NOTES ++++
projects / platform / upstream / syslinux.git / commitdiff