Difference between revisions of "CRO0"
| Line 167: | Line 167: | ||
|} | |} | ||
| − | Segment Table (12 bytes) | + | Segment Table entry (12 bytes) |
{| class="wikitable" border="1" | {| class="wikitable" border="1" | ||
! Offset | ! Offset | ||
| Line 185: | Line 185: | ||
| Segment id (0, 1, 2..) | | Segment id (0, 1, 2..) | ||
|} | |} | ||
| + | |||
| + | Import Table entry (8 bytes) | ||
| + | {| class="wikitable" border="1" | ||
| + | ! Offset | ||
| + | ! Size | ||
| + | ! Description | ||
| + | |- | ||
| + | | 0x0 | ||
| + | | 0x4 | ||
| + | | Name offset | ||
| + | |- | ||
| + | | 0x4 | ||
| + | | 0x4 | ||
| + | | Offset for symbol entry | ||
| + | |} | ||
| + | |||
| + | Symbol entry (12 bytes) | ||
| + | {| class="wikitable" border="1" | ||
| + | ! Offset | ||
| + | ! Size | ||
| + | ! Description | ||
| + | |- | ||
| + | | 0x0 | ||
| + | | 0x4 | ||
| + | | "Segment offset" for output. | ||
| + | |- | ||
| + | | 0x4 | ||
| + | | 0x1 | ||
| + | | Type (0=nothing/ignore, 2=38=write u32 absolute (unk+X), 3=write u32 relative (unk+X-out_ptr), 10=THUMB branch, 28=ARM32 branch, otherwise err, 29=unknown, 42=unknown) | ||
| + | |- | ||
| + | | 0x5 | ||
| + | | 0x1 | ||
| + | | Non-zero if last entry. | ||
| + | |- | ||
| + | | 0x6 | ||
| + | | 0x2 | ||
| + | | Unknown | ||
| + | |- | ||
| + | | 0x8 | ||
| + | | 0x4 | ||
| + | | X | ||
| + | |} | ||
| + | |||
| + | ARM32 branch instruction is constructed as follows: | ||
| + | If X > 0x2000000 or X < 0xFE000000, then skip. | ||
| + | If (X&1) == 1 then write "b 0" (infinite loop). | ||
| + | Else write as normal. | ||
Segment offset (4 bytes) | Segment offset (4 bytes) | ||
| Line 196: | Line 243: | ||
|- | |- | ||
| 4-31 | | 4-31 | ||
| − | | | + | | Offset into segment |
|} | |} | ||
Revision as of 09:32, 19 January 2014
| Offset | Size | Description |
|---|---|---|
| 0x0 | 0x80 | SHA-256 hash-table, verified by CRR |
| 0x80 | 0x04 | Magic "CRO0" |
| 0x84 | 0x04 | Code size |
| 0x88 | 0x08 | Unknown |
| 0x90 | 0x04 | File size |
| 0x94 | 0x1C | Unknown |
| 0xB0 | 0x04 | Code offset |
| 0xB4 | 0x04 | Code size |
| 0xB8 | 0x04 | unk1 offset |
| 0xBC | 0x04 | unk1 size |
| 0xC0 | 0x04 | Module Name offset |
| 0xC4 | 0xBC | Module Name size |
| 0xC8 | 0x04 | Segment Table offset |
| 0xCC | 0x04 | Segment Table num (size = num*12) |
| 0xD0 | 0x04 | Export Table offset |
| 0xD4 | 0x04 | Export Table num (size = num * 8) |
| 0xD8 | 0x04 | unk3 offset |
| 0xDC | 0x04 | unk3 num |
| 0xE0 | 0x04 | Export Strings offset |
| 0xE4 | 0x04 | Export Strings size |
| 0xE8 | 0x04 | Export Info offset |
| 0xEC | 0x04 | Export Info num (size = num * 8) |
| 0xF0 | 0x04 | unk4 offset |
| 0xF4 | 0x04 | unk4 num |
| 0xF8 | 0x04 | unk5 offset |
| 0xFC | 0x04 | unk5 num (size = num * 12) |
| 0x100 | 0x04 | Import Table 1 offset |
| 0x104 | 0x04 | Import Table 1 num (size = num * 4) |
| 0x108 | 0x04 | Import Table 2 offset |
| 0x10C | 0x04 | Import Table 2 num (size = num * 4) |
| 0x110 | 0x04 | Import Table 3 offset |
| 0x114 | 0x04 | Import Table 3 num (size = num * 4) |
| 0x118 | 0x04 | Import Strings offset |
| 0x11C | 0x04 | Import Strings size |
| 0x120 | 0x04 | unk8 offset |
| 0x124 | 0x04 | unk8 num |
| 0x128 | 0x04 | Import Info offset |
| 0x12C | 0x04 | Import Info num (size = num * 12) |
| 0x130 | 0x04 | unk9 offset |
| 0x134 | 0x04 | unk9 num |
Segment Table entry (12 bytes)
| Offset | Size | Description |
|---|---|---|
| 0x0 | 0x4 | Segment offset |
| 0x4 | 0x4 | Segment size |
| 0x8 | 0x4 | Segment id (0, 1, 2..) |
Import Table entry (8 bytes)
| Offset | Size | Description |
|---|---|---|
| 0x0 | 0x4 | Name offset |
| 0x4 | 0x4 | Offset for symbol entry |
Symbol entry (12 bytes)
| Offset | Size | Description |
|---|---|---|
| 0x0 | 0x4 | "Segment offset" for output. |
| 0x4 | 0x1 | Type (0=nothing/ignore, 2=38=write u32 absolute (unk+X), 3=write u32 relative (unk+X-out_ptr), 10=THUMB branch, 28=ARM32 branch, otherwise err, 29=unknown, 42=unknown) |
| 0x5 | 0x1 | Non-zero if last entry. |
| 0x6 | 0x2 | Unknown |
| 0x8 | 0x4 | X |
ARM32 branch instruction is constructed as follows:
If X > 0x2000000 or X < 0xFE000000, then skip. If (X&1) == 1 then write "b 0" (infinite loop). Else write as normal.
Segment offset (4 bytes)
| Bits | Description |
|---|---|
| 0-3 | Segment index for table |
| 4-31 | Offset into segment |
CRO with extension .cro is used for "DLLs". CRS with extension .crs can be used for storing "DLL" symbols as well. The end of the file is aligned to a 0x1000-byte boundary with 0xCC bytes. CRO0 files are usually stored under "romfs:/cro/".
The first hash-table entry hashes the 0x100-byte header following the hash-table. The following hash-table entries hash the sections specified in the header.
When the RO module loads the entire CRO into process memory(mapped in the 0x00100000-0x04000000 region), it modifies the mapped CRO data. The magic field is also changed to "FIXD".
Upon loading, the RO module will look for symbol "__aeabi_atexit" or "nnroAeabiAtexit_".