Table 159. Point On Elliptic Curve Fp Check; Table 160. Ecc Fp Scalar Multiplication - ST STM32WL55JC Reference Manual

Public key accelerator (PKA)
Parameters with direction
MODE
Curve prime order n
length
Curve modulus p length
Curve coefficient a sign
Curve coefficient |a|
Curve modulus value p
IN
Integer k
Curve base point G
coordinate x
Curve base point G
coordinate y
Hash of message z
Private key d
Curve prime order n
1. This integer is usually a cryptographically secure random number, but in some cases k could be
deterministically generated.
Parameters with direction
OUT
ERROR Result of signature
Note: If error output is different from zero the content of the PKA memory should be cleared to
avoid leaking information about the private key.
Extended ECDSA support
PKA also supports Extended ECDSA signature, for which the inputs and the outputs have
the same ECDSA signature
coordinates of the point kG. This extra output is defined in
712/1454
Table 162. ECDSA sign - Inputs
(1)
Table 163. ECDSA sign - Outputs
Signature part r (0 < r < n)
Signature part s (0 < s < n)
– 0x0: no error
– 0x1: signature part r is equal to 0
– 0x2: signature part s is equal to 0
(Table 162
Value (Note)
0x24
(in bits, not null)
(in bits, 8 < value < 640)
0x0: positive
0x1: negative
(Absolute value, |a| < p)
(Odd integer prime,
640
0 < p < 2 )
640
(0 ≤ k < 2 )
(x < p)
(y < p)
(z < 2M)
(positive integer)
(integer prime)
Value (Note)
and Table 163, respectively), with the addition of the
RM0453 Rev 2
Storage
PKA_CR
RAM@0x400
RAM@0x404
RAM@0x408
RAM@0x40C
RAM@0x460
RAM@0x508
RAM@0x55C
RAM@0x5B0
RAM@0xDE8
RAM@0xE3C
RAM@0xE94
Storage
RAM@0x700
RAM@0x754
RAM@0xEE8
Table 164.
RM0453
Size
6 bits
32 bits
EOS
Size
EOS
32 bits