Bugzilla ID: 1773 Cc: [email protected] [0] https://bugs.dpdk.org/show_bug.cgi?id=1773
Signed-off-by: Kai Ji <[email protected]> --- lib/eal/include/rte_memory.h | 68 ++++++++++++++++++++++++++++++++++++ 1 file changed, 68 insertions(+) diff --git a/lib/eal/include/rte_memory.h b/lib/eal/include/rte_memory.h index dcc0e69cfe..bbdef8e939 100644 --- a/lib/eal/include/rte_memory.h +++ b/lib/eal/include/rte_memory.h @@ -746,6 +746,74 @@ __rte_experimental void rte_memzero_explicit(void *dst, size_t sz); +/** + * @warning + * @b EXPERIMENTAL: this API may change without prior notice. + * + * Constant-time memory inequality comparison. + * + * This function compares two memory regions in constant time, making it + * resistant to timing side-channel attacks. The execution time depends only + * on the length parameter, not on the actual data values being compared. + * + * This is particularly important for cryptographic operations where timing + * differences could leak information about secret keys, passwords, or other + * sensitive data. + * + * @param a + * Pointer to the first memory region to compare + * @param b + * Pointer to the second memory region to compare + * @param n + * Number of bytes to compare + * @return + * false if the memory regions are identical, true if they differ + */ +__rte_experimental +static inline bool +rte_memneq_consttime(const void *a, const void *b, size_t n) +{ + const volatile uint8_t *pa = (const volatile uint8_t *)a; + const volatile uint8_t *pb = (const volatile uint8_t *)b; + uint8_t result = 0; + size_t i; + + for (i = 0; i < n; i++) + result |= pa[i] ^ pb[i]; + + return result != 0; +} + +/** + * @warning + * @b EXPERIMENTAL: this API may change without prior notice. + * + * Constant-time memory equality comparison. + * + * This function compares two memory regions in constant time, making it + * resistant to timing side-channel attacks. The execution time depends only + * on the length parameter, not on the actual data values being compared. + * + * This is particularly important for cryptographic operations where timing + * differences could leak information about secret keys, passwords, or other + * sensitive data. + * + * @param a + * Pointer to the first memory region to compare + * @param b + * Pointer to the second memory region to compare + * @param n + * Number of bytes to compare + * @return + * true if the memory regions are identical, false if they differ + */ +__rte_experimental +static inline bool +rte_memeq_consttime(const void *a, const void *b, size_t n) +{ + return !rte_memneq_consttime(a, b, n); +} + #ifdef __cplusplus } #endif -- 2.34.1
