CRYPTO_MEMCMP(3)           Library Functions Manual           CRYPTO_MEMCMP(3)

NAME
     CRYPTO_memcmp - constant time memory comparison

SYNOPSIS
     #include <openssl/crypto.h>

     int
     CRYPTO_memcmp(const void *a, const void *b, size_t len);

DESCRIPTION
     CRYPTO_memcmp() compares the len bytes pointed to by a and b for
     equality.  It takes an amount of time dependent on len, but independent
     of the contents of the memory regions pointed to by a and b.

RETURN VALUES
     CRYPTO_memcmp() returns 0 if the content of the memory regions is equal
     or non-zero otherwise.

HISTORY
     CRYPTO_memcmp() first appeared in OpenSSL 1.0.1d and has been available
     since OpenBSD 5.6.

BUGS
     Unlike memcmp(3) and timingsafe_memcmp(3), this function cannot be used
     to order the two memory regions.  In the current implementation, the
     return value is always greater than or equal to 0.

Linux 6.8.7-arch1-1             August 25, 2019            Linux 6.8.7-arch1-1