Datasheet

43.3.6.11.5 Code Example
PUKCL_PARAM PUKCLParam;
PPUKCL_PARAM pvPUKCLParam = &PUKCLParam;
// ! The Random Number Generator must be initialized and started
// ! following the directives given for the RNG on the chip
PUKCL (u2Option) = 0;
// Depending on the option specified, not all fields should be filled PUKCL
_ZpEcDsaGenerate(nu1ModBase) = <Base of the ram location of P>; PUKCL
_ZpEcDsaGenerate(u2ModLength) = <Byte length of P>;
PUKCL _ZpEcDsaGenerate(nu1CnsBase) = <Base of the ram location of Cns>;
PUKCL _ZpEcDsaGenerate(nu1PointABase) = <Base of the A point>;
PUKCL _ZpEcDsaGenerate(nu1PrivateKey) = <Base of the Private Key>;
PUKCL _ZpEcDsaGenerate(nu1ScalarNumber) = <Base of the ScalarNumber>;
PUKCL _ZpEcDsaGenerate(nu1OrderPointBase) = <Base of the order of A point>;
PUKCL _ZpEcDsaGenerate(nu1ABase) = <Base of the a parameter of the curve>;
PUKCL _ZpEcDsaGenerate(nu1Workspace) = <Base of the workspace>;
PUKCL _ZpEcDsaGenerate(nu1HashBase) = <Base of the SHA resulting hash>;
PUKCL_ZpEcDsaGenerate(u2ScalarLength) = < Length of ScalarNumber>;
...
// vPUKCL_Process() is a macro command, which populates the service name
// and then calls the library...
vPUKCL_Process(ZpEcDsaGenerateFast, pvPUKCLParam);
if (PUKCL (u2Status) == PUKCL_OK)
{
...
}
else // Manage the error
43.3.6.11.6 Constraints
No overlapping between either input and output are allowed. The following conditions must be avoided to
ensure that the service works correctly:
• nu1ModBase, nu1CnsBase, nu1PointABase, nu1PrivateKey, nu1ScalarNumber,
nu1OrderPointBase,nu1ABase, nu1Workspace or nu1HashBase are not aligned on 32-bit
boundaries
• {nu1ModBase, u2ModLength + 4}, {nu1CnsBase, u2ModLength + 8}, {nu1PointABase,
3*u2ModLength+ 12},{nu1PrivateKey, u2ScalarLength + 4},{nu1ScalarNumber, u2ScalarLength + 4},
{nu1OrderPointBase, u2ScalarLength + 4}, {nu1ABase, u2ModLength + 4}, {nu1Workspace,
<WorkspaceLength>} or {nu1HashBase, u2ScalarLength + 4} are not in Crypto RAM
• u2ModLength is either: < 12, > 0xffc or not a 32-bit length
• All overlapping between {nu1ModBase, u2ModLength + 4}, {nu1CnsBase, u2ModLength +8},
{nu1PointABase, 3*u2ModLength + 12}, {nu1PrivateKey, u2ScalarLength + 4}, {nu1ScalarNumber,
u2ScalarLength + 4}, {nu1OrderPointBase, u2ScalarLength + 4}, {nu1ABase, u2ModLength + 4},
{nu1Workspace, <WorkspaceLength>} and {nu1HashBase, u2ScalarLength + 4}
43.3.6.11.7 Status Returned Values
Table 43-86. ZpEcDsaGenerateFast Service Return Codes
Returned Status Importance Meaning
PUKCL_OK – The computation passed without problem. The
signature is the good one.
PUKCL_WRONG_SELECTNUMBER Warning The given value for nu1ScalarNumber is not good
to perform this signature generation.
SAM D5x/E5x Family Data Sheet
Public Key Cryptography Controller (PUKCC)
© 2019 Microchip Technology Inc.
Datasheet
DS60001507E-page 1534