Hi Tom, On Wed, 29 May 2024 at 14:43, Tom Rini <tr...@konsulko.com> wrote:
> On Wed, May 29, 2024 at 02:38:10PM -0400, Raymond Mao wrote: > > Hi Tom, > > > > On Wed, 29 May 2024 at 14:01, Tom Rini <tr...@konsulko.com> wrote: > > > > > On Wed, May 29, 2024 at 01:42:16PM -0400, Raymond Mao wrote: > > > > Hi Tom, > > > > > > > > On Wed, 29 May 2024 at 12:58, Tom Rini <tr...@konsulko.com> wrote: > > > > > > > > > On Tue, May 28, 2024 at 07:09:14AM -0700, Raymond Mao wrote: > > > > > > > > > > > Port mbedtls with dummy libc header files. > > > > > > Add mbedtls default config header file. > > > > > > Optimize mbedtls default config by disabling unused features to > > > > > > reduce the target size. > > > > > > Add mbedtls kbuild makefile. > > > > > > Add Kconfig and mbedtls config submenu. > > > > > [snip] > > > > > > diff --git a/lib/mbedtls/Kconfig b/lib/mbedtls/Kconfig > > > > > > new file mode 100644 > > > > > > index 00000000000..d6e77d56871 > > > > > > --- /dev/null > > > > > > +++ b/lib/mbedtls/Kconfig > > > > > > @@ -0,0 +1,25 @@ > > > > > > +menuconfig MBEDTLS_LIB > > > > > > + bool "Use mbedtls libraries" > > > > > > + select MBEDTLS_LIB_CRYPTO > > > > > > + select MBEDTLS_LIB_X509 > > > > > > + help > > > > > > + Enable mbedtls libraries > > > > > > + > > > > > > +if MBEDTLS_LIB > > > > > > + > > > > > > +config MBEDTLS_LIB_CRYPTO > > > > > > + bool "Crypto library" > > > > > > + help > > > > > > + Enable mbedtls crypto library > > > > > > + > > > > > > +config MBEDTLS_LIB_X509 > > > > > > + bool "X509 library" > > > > > > + help > > > > > > + Enable mbedtls X509 library > > > > > > + > > > > > > +config MBEDTLS_LIB_TLS > > > > > > + bool "TLS library" > > > > > > + help > > > > > > + Enable mbedtls TLS library > > > > > > + > > > > > > +endif # MBEDTLS_LIB > > > > > > > > > > We need much more granularity here, and to re-think some existing > > > > > symbols too perhaps. What we should be able to do is pick mbedTLS > or > > > > > "legacy SW implementation" or "HW implementation" for the various > > > > > algorithms, and that in turn can have some higher level grouping > to it. > > > > > This should then negate a bunch of the Makefile work you're doing > as we > > > > > won't have CONFIG_SHA256 enabled as we'll have > > > CONFIG_MBEDTLS_LIB_SHA256 > > > > > or whatever enabled. > > > > > > > > > > > > > I think we should use CONFIG_MBEDTLS_LIB_[CRYPTO,X509,TLS] for > high-level > > > > grouping. > > > > Underneath, the CONFIG_SHA[1,256,512] switches (and other crypto > options) > > > > can be > > > > used as sub build options in both MbedTLS and "legacy libs". > > > > > > > > Take hash as an example, if the users prefer to use MbedTLS other > than > > > > "legacy libs" for > > > > hash operation, CONFIG_MBEDTLS_LIB_CRYPTO should be defined as the > main > > > > switch > > > > (the users can still prefer to use "legacy libs" for X509 by > > > > keeping CONFIG_MBEDTLS_LIB_X509 > > > > disabled). > > > > Then enable the algorithms they need (e.g. CONFIG_SHA256) - the > algorithm > > > > options works > > > > for both MbedTLS and "legacy libs". > > > > > > > > HW implementations with MbedTLS (aka, Alternative algorithms in > MbedTLS) > > > is > > > > another > > > > topic which is not covered in this patch set (It needs to migrate > each > > > > vendor's solution under > > > > MbedTLS alternative algorithm). > > > > Current patch set is focused on SW implementation with MbedTLS. > > > > > > The "easy" problem with what's in v3 is that X509 and CRYPTO are > > > select'd under the main heading. > > > > Not sure if I get what you mentioned, currently all MbedTLS options are > > under > > Library routines > Security support > > Do you think we should keep them in other places? > > > > > > > The harder problem is that we > > > intentionally have granularity for SHA256, SHA512, etc, etc and all of > > > that goes away with the current Kconfig option if you select mbedTLS. > We > > > need to bring that back. And we shouldn't need to have all of the ifneq > > > statements in Makefiles because both CONFIG_SHA256 and > > > CONFIG_MBEDLTS_LIB_CRYPTO_SHA256 will not be true (Or possibly, > > > CONFIG_SHA256 gates things U-Boot's internal API for sha256'ing > > > something and CONFIG_LEGACY_SHA256 controls building lib/sha256.c). > > > > > > I think we should not introduce new ones like CONFIG_LEGACY_, > > CONFIG_SHA[1,256,512] should be used no matter whether MbedTLS is > > enabled or not. > > I understand your concern, I will bring CONFIG_SHA[1,256,512] back when > > MbedTLS is enabled. Those options should control the options in the > MbedTLS > > default config file. > > My concern is that we do not have the correct level of granularity, and > that can partly be seen by the number of ifneq(...) statements being > added around already conditional logic. We should have almost none of > those, in the end, is what I'm saying. We have a mechanism for > configuring the build, Kconfig, and that should drive the decisions as > much as possible. > > The `ifneq(ONFIG_MBEDTLS_LIB_*)` statements are due to the fact that we still need lib/Makefile and lib/crypto/Makefile when building hash and x509 stuffs with MbedTLS enabled. To address this, I guess we have to first refactor all "legacy libs" that will be replaced by MbedTLS: Move md5, sha* from lib to to a new dir lib/hash and move public_key, rsapubkey*, rsa_helper, x509*, pkcs7*,mscode* from lib/crypto to a new dir lib/x509. When they are all independent modules with separated Makefile, we can remove `ifneq(ONFIG_MBEDTLS_LIB_*)` and all can be driven in lib/Makefile. Is that something you expect? If yes I can do this for v4, or put it into another prerequisite/refactor series. Regards, Raymond