This change allows selectively modifying the default plugin list by setting
the `load` setting of individual plugins (e.g. to disable them or to change
their priority) without enabling charon.load_modular and having to configure
a section and a load statement for every plugin.
If a function we whitelist allocates memory while leak detective is enabled
but only frees it after LD has already been disabled, free() will get called
with invalid pointers (not pointing to the actually allocated memory by LD),
which will cause checks in the C library to fail and the program to crash.
This tries to detect such cases and calling free with the correct pointer.
Lots of static data is allocated in this function, which isn't freed until
the library is unloaded (we can't call OPENSSL_cleanup() as initialization
would fail when calling it again later). When enabling the leak
detective the test runner eventually crashes as all the data allocated during
initialization has an invalid size when freed after leak detective has been
unloaded.
There is currently no way to compare the outer and inner algorithms
encoded in a parsed CRL. X509_CRL_verify() does not seem to check that
either, though (unlike X509_verify()).
We can't call OPENSSL_cleanup() as that would prevent us from
re-initializing the library again (which we use in the Android app, that
loads/unloads plugins).
Newer versions of GCC are too "smart" and replace a call to malloc(X)
followed by a call to memset(0,X) with a call co calloc(), which obviously
results in an infinite loop when it does that in our own calloc()
implementation. Using `volatile` for the variable storing the total size
prevents the optimization and we actually call malloc().
memeq() is currently used to compare these but if there is padding that
is not initialized the same for two instances the comparison fails.
Using this function ensures the objects are compared correctly.
If the af-alg plugin is enabled, but kernel support is missing, we get
an error line during startup for each probed algorithm. This is way too
verbose, so just skip probing if AF_ALG is unsupported.
Tobias Brunner