FIRM: Difference between revisions

Moved info from elsewhere since it's not really relevant there.
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* Executes a while(<value of byte at current pos in RSA message>). When the second_byte in the message is 0x1, the byte at curpos must be 0xFF(otherwise the non-zero value of the byte at curpos doesn't matter). This loop must find a zero byte before offset 0x7F in the message otherwise an error is returned.
* Executes a while(<value of byte at current pos in RSA message>). When the second_byte in the message is 0x1, the byte at curpos must be 0xFF(otherwise the non-zero value of the byte at curpos doesn't matter). This loop must find a zero byte before offset 0x7F in the message otherwise an error is returned.
* Returns an address for msg_curpos+1.
* Returns an address for msg_curpos+1.
With the code in TWL_FIRM, the actual "totalhashdatasize" in the RSA message must be <= <expected hashdata_size>(0x74 for bootloader). The TWL_FIRM code copies the RSA "hashdata" to the output buffer, using the actual size of the RSA "hashdata".
totalhashdatasize = rsasig_bytesize - above position in the message for the hashdata. The actual "totalhashdatasize" in the RSA message must be <= <expected hashdata_size>(0x74 for bootloader). The TWL_FIRM code copies the RSA "hashdata" to the output buffer, using the actual size of the RSA "hashdata".


== FIRM Launch Parameters ==
== FIRM Launch Parameters ==