Revision as of 12:38, 1 July 2017

This is the Switch equivalent of 3DS exheader. This is the file with extension ".npdm" in {Switch ExeFS}. The size of this file varies.

ACID

Offset	Size	Description
0	0x100	RSA-2048 signature
0x100	0x100	RSA-2048 public key
0x200	0x4	Magic "ACID".
0x204	0x8	Zeroes
0x20C	0x4	Format version? (1)
0x210	0x8	Title id
0x218	0x8	Title id again
0x220	0x4	#FS Access Control offset
0x224	0x4	#FS Access Control size
0x228	0x4	#Service Access Control offset
0x22C	0x4	#Service Access Control size
0x230	4	#Kernel Access Control offset
0x234	4	#Kernel Access Control size
0x238	0x8	Padding

Looks like an old crappy version of ACID. It has the guessed version field 0 instead of 1.

Word	Bit	Description
0		Version? Always 1.
1	0	MountContent* is accessible when set.
0	3	This is only bit set for ShopN in the permissions-u32.

This is a list of service-name strings which the title has access to, with the following structure:

 +0: control_byte
 +1: {service-name without nul-terminator}

Bitmask 0x0F in control_byte is the {length of the service-name without nul-terminator} - 1.

Bitmask 0x80 in control_byte means service is allowed to be registered.

The service string can contain a wildcard * character.

On Switch, descriptors are identified by pattern 01..11 in low bits.

Pattern of bits 15-0	Type	Fields
`0bxxxxxxxxxxxx0111`	Kernel flags	?
`0bxxxxxxxxxxx01111`	Syscall mask	Bits 29-31: Syscall mask table index; Bits 5-28: mask
`0bxxxxxxxxx0111111`	Map IO page	Bits 7-31: page
`0bxxxxxxxx01111111`	Map IO range	Bits 7-31: page then size alternating
`0bxxxxx11111111111`	Interrupt pair	Bits 12-21: irq0, bits 20-31: irq1, 0x3FF means empty.

@@ Line 152: / Line 152: @@
 = Kernel Access Control =
-Like the 3DS, the switch has a number of kernel capability descriptors. Unlike 3ds, where descriptors were identified by pattern 11..10 in high bits, on switch descriptors are identified by pattern 01..11 in low bits.
+On Switch, descriptors are identified by pattern 01..11 in low bits.
 {| class="wikitable" border="1"
 |-
-! Pattern of bits 20-31
+! Pattern of bits 15-0
 ! Type
 ! Fields
 |-
-| <code>0bxxxxxxxx0111?</code>
+| <code>0bxxxxxxxxxxxx0111</code>
-| Interrupt info?
+| Kernel flags
 | ?
 |-
-| <code>0bxxxxxxx01111</code>
+| <code>0bxxxxxxxxxxx01111</code>
-| System call mask
+| Syscall mask
-| Bits 29-31: System call mask table index; Bits 5-28: mask
+| Bits 29-31: Syscall mask table index; Bits 5-28: mask
 |-
-| <code>0bxxxxx0111111?</code>
+| <code>0bxxxxxxxxx0111111</code>
-| Kernel release version?
+| Map IO page
-| ?
+| Bits 7-31: page
-|-
-| <code>0bxxxx01111111?</code>
-| Handle table size?
-| ?
 |-
-| <code>0bxxx011111111?</code>
+| <code>0bxxxxxxxx01111111</code>
-| Kernel flags?
+| Map IO range
-| ?
+| Bits 7-31: page then size alternating
 |-
-| <code>0bx0111111111?</code>
+| <code>0bxxxxx11111111111</code>
-| Map address range?
+| Interrupt pair
-| ?
+| Bits 12-21: irq0, bits 20-31: irq1, 0x3FF means empty.
-|-
-| <code>0b011111111111?</code>
-| Map memory page?
-| ?
 |}