Config file is written to a temp file and then it is renamed to the
original config file. However, it is possible that the rename operation
will be commited to storage while file data will be still in cache
causing original config file to be empty or partially written in case of
a system reboot without a clean shutdown. Make this less likely to occur
by forcing the data to be written to the storage device before renaming
the file.
Signed-off-by: Dmitry Shmidt <dimitrysh@google.com>
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>
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>
