RSA Registers: Difference between revisions

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RSA_MOD: Note about attack to read RSA_EXPFIFO indirectly
 
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= Overview =
The RSA module is essentially a hardware-accelerated modular exponentiation engine. It is specially optimized for RSA applications, so its behavior can be incoherent when RSA's invariants are broken.
=== Observed edge cases ===
* if 2 divides mod, output == 0
= Registers =
= Registers =
{| class="wikitable" border="1"
{| class="wikitable" border="1"
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| [[#RSA_EXPFIFO|RSA_EXPFIFO]]
| [[#RSA_EXPFIFO|RSA_EXPFIFO]]
| 0x1000B200
| 0x1000B200
| 0x04
| 0x100 (can handle u32 writes to any aligned position in the FIFO)
|
|
|-
|-
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|-
|-
| 1
| 1
| ?
| Interrupt enable (1=enable, 0=disable)
|-
|-
| 4-7
| 4-7
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|-
|-
| 8
| 8
| Endianness (1=Little endian, 0=Big endian)
| Endianness (1=Little endian, 0=Big endian). Affects RSA_EXPFIFO, RSA_MOD, and RSA_TXT.
|-
|-
| 9
| 9
| Word order (1=Normal order, 0=Reversed order)
| Word order (1=Normal order, 0=Reversed order). Affects RSA_MOD and RSA_TXT.
|}
|}


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| Key write-protect, this bit is RW. (0 = no protection, 1 = protected)
| Key write-protect, this bit is RW. (0 = no protection, 1 = protected)
|-
|-
| 30-2
| 2
| Key read-protect, this bit is RW. (0 = no protection, 1 = protected)
|-
| 30-3
| ?
| ?
|-
|-
| 31
| 31
| ?
| Key slot protect. Makes all other bits in this reg read-only until reset
|}
|}