Difference between revisions of "FSPXI:ReadFileSHA256"

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m (Steveice10 moved page FSPXI:ReadFileWrapper to FSPXI:ReadFileSHA256)
 
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| File(/archive?) handle lower word
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| File handle lower word
 
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| Size of second memory block
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| Size of read buffer
 
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| Size of first memory block
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| Size of hashtable
 
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| (size of first mem block << 8)  <nowiki>|</nowiki> 4
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| (size of hashtable << 8)  <nowiki>|</nowiki> 4
 
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| Pointer to first memory block
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| Pointer to hashtable
 
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| (size of second mem block << 8)  <nowiki>|</nowiki> 0x14
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| (size of read buffer << 8)  <nowiki>|</nowiki> 0x14
 
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| 11
 
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| Pointer to second memory block
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| Pointer to read buffer
 
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The data read are stored in the second memory block. The first memory block is filled with hashes, in an unknown manner.
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The data read are stored in the read buffer. For each 0x1000-byte block read, a SHA256 hash of the block is stored in the hashtable.
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It is unknown how hashing behaves if the read offset/size are not aligned to a 0x1000-byte boundary.

Latest revision as of 10:18, 16 January 2016

Request[edit]

Index Word Description
0 Header code [0x004D01C4]
1 File handle lower word
2 File handle upper word
3 Offset lower word
4 Offset upper word
5 Size of read buffer
6 Unknown (always 0x00001000)
7 Size of hashtable
8 (size of hashtable << 8) | 4
9 Pointer to hashtable
10 (size of read buffer << 8) | 0x14
11 Pointer to read buffer

Response[edit]

Index Word Description
0 Header code
1 Result code
2 Size read
3 4

The data read are stored in the read buffer. For each 0x1000-byte block read, a SHA256 hash of the block is stored in the hashtable.

It is unknown how hashing behaves if the read offset/size are not aligned to a 0x1000-byte boundary.