Non FIPS algorithms are not normally allowed in FIPS mode.
Any attempt to use them via high level functions will return an error.
The low level non-FIPS algorithm functions cannot return errors so they
produce assertion failures. HMAC also has to give an assertion error because
it (erroneously) can't return an error either.
There are exceptions (such as MD5 in TLS and non cryptographic use of
algorithms) and applications can override the blocking and use non FIPS
algorithms anyway.
For low level functions the override is perfomed by prefixing the algorithm
initalization function with "private_" for example private_MD5_Init().
For high level functions an override is performed by setting a flag in
the context.
libdes (which is still used out there) or other des implementations,
the OpenSSL DES functions are renamed to begin with DES_ instead of
des_. Compatibility routines are provided and declared by including
openssl/des_old.h. Those declarations are the same as were in des.h
when the OpenSSL project started, which is exactly how libdes looked
at that time, and hopefully still looks today.
The compatibility functions will be removed in some future release, at
the latest in version 1.0.
sure they are available in opensslconf.h, by giving them names starting
with "OPENSSL_" to avoid conflicts with other packages and by making
sure e_os2.h will cover all platform-specific cases together with
opensslconf.h.
I've checked fairly well that nothing breaks with this (apart from
external software that will adapt if they have used something like
NO_KRB5), but I can't guarantee it completely, so a review of this
change would be a good thing.
"Jan Mikkelsen" <janm@transactionsite.com> correctly states that the
OpenSSL header files have #include's and extern "C"'s in an incorrect
order. Thusly fixed.