This function is meant for comparing passwords or hash values where
difference in execution time could provide external observer information
about the location of the difference in the memory buffers. The return
value does not behave like os_memcmp(), i.e., os_memcmp_const() cannot
be used to sort items into a defined order. Unlike os_memcmp(),
execution time of os_memcmp_const() does not depend on the contents of
the compared memory buffers, but only on the total compared length.
Signed-off-by: Jouni Malinen <j@w1.fi>
Just the usual, with a new function os_reltime_initialized()
thrown in that checks whether time has ever been retrieved
(time can't be completely zero).
Signed-hostap: Johannes Berg <johannes.berg@intel.com>
This helper functions checks whether a given entry has expired,
given the last active timestamp, the current time, and a timeout.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Relative time shouldn't be calculated based on gettimeofday
because that clock can jump (e.g., when the time is adjusted
by the system administrator.)
On systems where that is available, use CLOCK_BOOTTIME (on
fairly recent Linux systems, this clock takes into account
the time spend suspended) or CLOCK_MONOTONIC (on Linux and
some POSIX systems, this clock is just freely running with
no adjustments.)
Reported-by: Holger Schurig <holgerschurig@gmail.com>
Signed-hostap: Johannes Berg <johannes.berg@intel.com>
os_strlpcy() should be used instead of os_strncpy() to guarantee null
termination. Since there are no remaining strncpy uses, remove
os_strncpy() definition.
Signed-hostap: Jouni Malinen <j@w1.fi>
This function can be used as a wrapper for os_realloc(ptr, nmemb * size)
when a reallocation is used for an array. The main benefit over
os_realloc() is in having an extra check to catch integer overflows in
multiplication. This is similar to the os_zalloc() to os_calloc() move.
Signed-hostap: Jouni Malinen <j@w1.fi>
This function can be used as a wrapper for os_zalloc(nmemb * size) when
an allocation is used for an array. The main benefit over os_zalloc() is
in having an extra check to catch integer overflows in multiplication.
Signed-hostap: Jouni Malinen <j@w1.fi>
WPA_TRACE=y builds will now verify that memory allocation in done
consistently using os_{zalloc,malloc,realloc,strdup,free} (i.e., no
mixing of os_* functions and unwrapper functions). In addition, some
common memory allocation issues (double-free, memory leaks, etc.) are
detected automatically.
