Compile FIPS 140 integrity check only when building shared library

[ueno]

When leancrypto is compiled as a static library with
-Ddefault_library=static, it fails with:

../internal/src/fips_integrity_checker_elf.c:77:10: fatal error: fips_integrity_checker_values.h: No such file or directory
   77 | #include "fips_integrity_checker_values.h"
      |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Given the FIPS 140 integrity check only works with shared library, as
it utilizes the ELF sections, this adds an extra check on
build_shared to avoid the compilation error.

Originally spotted by GnuTLS CI at: https://gitlab.com/dueno/gnutls/-/jobs/9425635915#L509

[ueno]

Not sure about the CI failures; all tests with -Ddefault_library=shared/static/both succeed on my environment (Fedora 41).

[smuellerDD]

Am Montag, 17. März 2025, 08:57:01 Mitteleuropäische Normalzeit schrieb Daiki Ueno: Hi Daiki,

ueno left a comment (smuellerDD/leancrypto#23) Not sure about the CI failures; all tests with `-Ddefault_library=shared/static/both` succeed on my environment (Fedora 41).

I fixed the failures with the last patch. It is a bummer that this patch is needed. Daiki, do you happen to have an idea why the constructors are not executed when compiling the library statically? Ciao Stephan

[ueno]

Thank you for merging and fixing the issue with constructor :-)

Daiki, do you happen to have an idea why the constructors are not executed
when compiling the library statically?

Afaik constructors are run by a dynamic linker, after determining the correct order of initialization/finalization, so there is no way to ensure that with static libraries:
https://www.akkadia.org/drepper/dsohowto.pdf#page=12

[smuellerDD]

Am Dienstag, 18. März 2025, 13:54:46 CET schrieb Daiki Ueno: Hi Daiki,

ueno left a comment (smuellerDD/leancrypto#23) Thank you for merging and fixing the issue with constructor :-) > Daiki, do you happen to have an idea why the constructors are not executed when compiling the library statically? Afaik constructors are run by a dynamic linker, after determining the correct order of initialization/finalization, so there is no way to ensure that with static libraries: https://www.akkadia.org/drepper/dsohowto.pdf#page=12

Right, but I thought when the static library is finally linked into the executable, the constructor functions are initialized. That said, Daiki, may I suggest to add an lc_init(0) call to GnuTLS? Otherwise you will not run the accelerated implementations for hashes. Ciao Stephan

[ueno]

Thank you; I've filed https://gitlab.com/gnutls/gnutls/-/merge_requests/1942