GD32W51x User Manual
988
of parameters used by ECDSA verification
.
Table 29-8. Range of parameters used by ECDSA verification
Param eters
Range
input
Curve prime order n
length (LEN)
0<LEN≤640
Curve modulus p
length (M)
0<M≤640
Sign of curve
coefficient a
0x0: positive
0x1: negative
Curve coefficient |a|
Absolute value |a|
<
p
Curve modulus p
Odd prime
0<p< 2
M
x coordinate of base
point G
x
<p
y coordinate of base
point G
y
<p
Public key curve
point Q coordinate
x
Q
x
Q
<p
Public key curve
point Q coordinate
y
Q
y
Q
<p
Signature part r
0<r<n
Signature part s
0<s<n
Hash of message z
z<2
LEN
Curve prime order n
prime
n<2
LEN
output
verification result
0x0: verification valid
Not 0x0: verification invalid
29.3.6.
PKCAU operation process
The PKCAU can be enabled by setting the PKCAUEN bit in PKCAU_CTL register. When the
PKCAU is performing a calculation, the PKCAUEN should not be cleared, or else the ongoing
operation is terminated and the content in PKCAU RAM will not be guaranteed.
When PKCAUEN is 0, the application can still access PKCAU RAM through the AHB interface.
Operation process in normal mode
The flows below applies to all operations listed in MODSEL[5:0] bits in the PKCAU_CTL
register.
1.
After system reset, the PKCAU RAM is to be erased from the beginning to the end. During
this period, the BUSY bit in PKCAU_STAT register is set. All operation to PKCAU RAM
should not carry out until the BUSY bit is 0;