This function can fail in theory since the SHA-1 functions are
allowed to return an error. While this does not really happen in
practice (we would not get this far if SHA-1 does not work), it is
cleaner to include the error handling here to keep static analyzers
happier. [Bug 421]
Signed-hostap: Jouni Malinen <j@w1.fi>
This commit adds a new wrapper, random_get_bytes(), that is currently
defined to use os_get_random() as is. The places using
random_get_bytes() depend on the returned value being strong random
number, i.e., something that is infeasible for external device to
figure out. These values are used either directly as a key or as
nonces/challenges that are used as input for key derivation or
authentication.
The remaining direct uses of os_get_random() do not need as strong
random numbers to function correctly.