Update to MD light section
Mostly to reflect this has been implemented, and remove references to
temporary remains from the previous strategy (hash_info, legacy_or_psa)
which would probably be more confusing than helpful at this point.
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
diff --git a/docs/architecture/psa-migration/md-cipher-dispatch.md b/docs/architecture/psa-migration/md-cipher-dispatch.md
index 76081de..12b486a 100644
--- a/docs/architecture/psa-migration/md-cipher-dispatch.md
+++ b/docs/architecture/psa-migration/md-cipher-dispatch.md
@@ -323,8 +323,6 @@
### MD light
-https://github.com/Mbed-TLS/mbedtls/pull/6474 implements part of this specification, but it's based on Mbed TLS 3.2, so it needs to be rewritten for 3.3.
-
#### Definition of MD light
MD light is a subset of `md.h` that implements the hash calculation interface described in ”[Designing an interface for hashes](#designing-an-interface-for-hashes)”. It is activated by `MBEDTLS_MD_LIGHT` in `mbedtls_config.h`.
@@ -454,31 +452,7 @@
#### Error code conversion
-After calling a PSA function, call `mbedtls_md_error_from_psa` to convert its status code. This function is currently defined in `hash_info.c`.
-
-### Migration to MD light
-
-#### Migration of modules that used to call MD and now do the legacy-or-PSA dance
-
-Get rid of the case where `MBEDTLS_MD_C` is undefined. Enable `MBEDTLS_MD_LIGHT` in `build_info.h`.
-
-#### Migration of modules that used to call a low-level hash module and now do the legacy-or-PSA dance
-
-Switch to calling MD (light) unconditionally. Enable `MBEDTLS_MD_LIGHT` in `build_info.h`.
-
-#### Migration of modules that call a low-level hash module
-
-Switch to calling MD (light). Enable `MBEDTLS_MD_LIGHT` in `build_info.h`.
-
-#### Migration of use-PSA mixed code
-
-Instead of calling `hash_info.h` functions to obtain metadata, get it from `md.h`.
-
-Optionally, code that currently tests on `MBEDTLS_USE_PSA_CRYPTO` just to determine whether to call MD or PSA to calculate hashes can switch to just having the MD variant.
-
-#### Remove `legacy_or_psa.h`
-
-It's no longer used.
+After calling a PSA function, call `mbedtls_md_error_from_psa` to convert its status code.
### Support all legacy algorithms in PSA
@@ -517,10 +491,6 @@
Work in progress on this conversion is at https://github.com/gilles-peskine-arm/mbedtls/tree/hash-unify-ids-wip-1
-#### Get rid of the hash_info module
-
-The hash_info module is redundant with MD light. Move `mbedtls_md_error_from_psa` to `md.c`, defined only when `MBEDTLS_MD_SOME_PSA` is defined. The rest is no longer used.
-
#### Unify HMAC with PSA
PSA has its own HMAC implementation. In builds with both `MBEDTLS_MD_C` and `PSA_WANT_ALG_HMAC` not fully provided by drivers, we should have a single implementation. Replace the one in `md.h` by calls to the PSA driver interface. This will also give mixed-domain modules access to HMAC accelerated directly by a PSA driver (eliminating the need to a HMAC interface in software if all supported hashes have an accelerator that includes HMAC support).