NSO0 - Nintendo File Formats

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An NSO0 file contains an executable.

Offset	Size	Description
0x0	4	Magic number (`NSO0`)
0x4	4	Version (always 0)
0x8	4	Padding (always 0)
0xC	4	Flags
0x10	4	Offset to `.text` segment in file (absolute)
0x14	4	Address of `.text` segment in memory
0x18	4	Size of `.text` segment in memory
0x1C	4	Offset to null-terminated module name in file (absolute)
0x20	4	Offset to `.rodata` segment in file (absolute)
0x24	4	Address of `.rodata` segment in memory
0x28	4	Size of `.rodata` segment in memory
0x2C	4	Size of module name, including null terminator
0x30	4	Offset to `.data` segment in file (absolute)
0x34	4	Address of `.data` segment in memory
0x38	4	Size of `.data` segment in memory
0x3C	4	Size of `.bss` segment in memory
0x40	32	Module id (random bytes / hash)
0x60	4	Size of `.text` segment in file
0x64	4	Size of `.rodata` segment in file
0x68	4	Size of `.data` segment in file
0x6C	28	Padding (always 0)
0x88	4	“Embedded offset” (?)
0x8C	4	“Embedded size” (?)
0x90	4	Offset to `.dynstr` section, relative to `.rodata` segment
0x94	4	Size of `.dynstr` section
0x98	4	Offset to `.dynsym` section, relative to `.rodata` segment
0x9C	4	Size of `.dynsym` section
0xA0	32	SHA-256 of decompressed `.text` segment
0xC0	32	SHA-256 of decompressed `.rodata` segment
0xE0	32	SHA-256 of decompressed `.data` segment
0x100		Null-terminated module name
		`.text` segment data (optionally compressed)
		`.rodata` segment data (optionally compressed)
		`.data` segment data (optionally compressed)

Notes:

The module name seems to be empty for games.
The .text, .rodata and .data segments do not need to be aligned to word boundary (there is no padding between them).

Flag	Description
`0x1`	`.text` segment is compressed
`0x2`	`.rodata` segment is compressed
`0x4`	`.data` segment is compressed
`0x8`	`.text` hash is valid
`0x10`	`.rodata` hash is valid
`0x20`	`.data` hash is valid
`0x40`	Execute-only memory is enabled
`0x80`	ZBIC compression is used instead of LZ4