(see the comments section of the Reddit post for what this all means)





--- DEFINING THE POLICY ---





james@server:~/0x10c-build> cat ../0x10c/kernel/stubsys/policy.example
defaults
{
    kernel=@KERNEL_FOLDER@/stubsys.dkrn16
    jumplist=@KERNEL_FOLDER@/stubsys.djmp16
    symbols=@KERNEL_FOLDER@/stubsys.dsym16
}

# image is the .executable format. for applications that will
# be loaded at runtime.  if this is not defined, the linker will
# use .image-direct. instead.
format(image):
    # offset all references to be relative to 0x1000
    offset 0x1000
    # call upon image-direct to perform the rest
    chain image-direct

# image-direct is the .executable format. for applications that
# are linked directly against the kernel.
format(image-direct):
    # write out the code (the linker has already
    # attached the kernel)
    write code

# internal format that writes the adjustment entries.
internal(write-adjustment):
    # write out adjustment table
    write total(adjustment)
    for $i from 0 to total(adjustment)
        write field(adjustment, $i, address)
    endfor

# internal format that writes the provided entries.
internal(write-provided):
    # write out provided table
    write total(provided)
    for $i from 0 to total(provided)
        write field(provided, $i, label_size)
        write field(provided, $i, label_text)
        write field(provided, $i, address)
    endfor

# shared is a custom format supported by this kernel
# in this case it.s a shared library, but we can make
# any definition here.
format(shared):
    # write out magic header
    write words(0x8A5F, 0x68FF)
    # write out tables
    chain write-adjustment
    chain write-provided
    # write out the code
    chain image-direct

# an example of defining a relocatable application
format(relocatable):
    # write out magic header
    write words(0x1234, 0x5678)
    # write out tables
    chain write-adjustment
    # write out the code
    chain image-direct





--- PARSING THE POLICY ---





james@server:~/0x10c-build> dtpolicy/dtpolicy ../0x10c/kernel/stubsys/policy.example print         
== settings ==
kernel = @KERNEL_FOLDER@/stubsys.dkrn16
jumplist = @KERNEL_FOLDER@/stubsys.djmp16
symbols = @KERNEL_FOLDER@/stubsys.dsym16

== policies ==
 - image
 - image-direct
 - write-adjustment
 - write-provided
 - shared
 - relocatable

== policy: image ==
    offset 4096
    chain image-direct

== policy: image-direct ==
    write code

== policy: write-adjustment ==
    write total(adjustment)
    for $i from 0 to total(adjustment)
        write field(adjustment, $i, address)
    endfor

== policy: write-provided ==
    write total(provided)
    for $i from 0 to total(provided)
        write field(provided, $i, label_size)
        write field(provided, $i, label_text)
        write field(provided, $i, address)
    endfor

== policy: shared ==
    write words(35423, 26879)
    chain write-adjustment
    chain write-provided
    chain image-direct

== policy: relocatable ==
    write words(4660, 22136)
    chain write-adjustment
    chain image-direct





--- EVALUATING THE POLICY ---





james@server:~/0x10c-build> dtpolicy/dtpolicy ../0x10c/kernel/stubsys/policy.example execute image 
== executing: image ==
offset called with 4096
code called
write called with:
    1
    2
    3
    4
    5
    6
james@server:~/0x10c-build> dtpolicy/dtpolicy ../0x10c/kernel/stubsys/policy.example execute image-direct
== executing: image-direct ==
code called
write called with:
    1
    2
    3
    4
    5
    6
james@server:~/0x10c-build> dtpolicy/dtpolicy ../0x10c/kernel/stubsys/policy.example execute shared      
== executing: shared ==
write called with:
    26320
    26528
total called with 278
write called with:
    3
total called with 278
added $i to the list of variables.
field called with 278, 0, 288
write called with:
field called with 278, 1, 288
write called with:
field called with 278, 2, 288
write called with:
removed $i to the list of variables.
total called with 279
write called with:
    3
total called with 279
added $i to the list of variables.
field called with 279, 0, 286
write called with:
field called with 279, 0, 287
write called with:
field called with 279, 0, 288
write called with:
field called with 279, 1, 286
write called with:
field called with 279, 1, 287
write called with:
field called with 279, 1, 288
write called with:
field called with 279, 2, 286
write called with:
field called with 279, 2, 287
write called with:
field called with 279, 2, 288
write called with:
removed $i to the list of variables.
code called
write called with:
    1
    2
    3
    4
    5
    6
james@server:~/0x10c-build> dtpolicy/dtpolicy ../0x10c/kernel/stubsys/policy.example execute relocatable
== executing: relocatable ==
write called with:
    27480
    27688
total called with 278
write called with:
    3
total called with 278
added $i to the list of variables.
field called with 278, 0, 288
write called with:
field called with 278, 1, 288
write called with:
field called with 278, 2, 288
write called with:
removed $i to the list of variables.
code called
write called with:
    1
    2
    3
    4
    5
    6