mcuxCsslMemory_Compare Function Definitions

mcuxCsslMemory_Compare Function Definitions More...

Functions
mcuxCsslMemory_CompareResult_t	mcuxCsslMemory_Compare (mcuxCsslParamIntegrity_Checksum_t chk, void const *lhs, void const *rhs, size_t cnt)
	Compares the two memory regions lhs and rhs. More...

Detailed Description

mcuxCsslMemory_Compare Function Definitions

Function Documentation

mcuxCsslMemory_Compare()

mcuxCsslMemory_CompareResult_t mcuxCsslMemory_Compare	(	mcuxCsslParamIntegrity_Checksum_t	chk,
		void const *	lhs,
		void const *	rhs,
		size_t	cnt
	)

Compares the two memory regions lhs and rhs.

The implementation is secure in the following aspects:

• Constant execution time: The execution sequence of the code is always identical for equal cnt parameters, i.e. no branches are performed based on the data in lhs or rhs.
• Parameter integrity protection: An incorrect parameter checksum makes the function return immediately.
• Code flow protection: The function call is protected. Additionally, the result depends on all steps of the calculation.

Parameters

chk	The parameter checksum, generated with mcuxCsslParamIntegrity_Protect.
lhs	The left-hand side data to compare. Must not be NULL.
rhs	The right-hand side data to compare. Must not be NULL.
cnt	The number of bytes to compare. Must be different from zero.

Returns

A status code encapsulated in a flow-protection type.

Return values

MCUXCSSLMEMORY_COMPARE_EQUAL	If the contents of lhs and rhs are equal.
MCUXCSSLMEMORY_COMPARE_NOT_EQUAL	If the contents of lhs and rhs are not equal.
MCUXCSSLMEMORY_COMPARE_INVALID_PARAMETER	If one of the parameters was invalid (i.e. lhs or rhs was NULL or cnt was zero).
MCUXCSSLMEMORY_COMPARE_FAULT	If a fault was detected.