Update psa-limitations.md
For recent work and latest plans.
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
diff --git a/docs/architecture/psa-migration/psa-limitations.md b/docs/architecture/psa-migration/psa-limitations.md
index c368023..b81aeb4 100644
--- a/docs/architecture/psa-migration/psa-limitations.md
+++ b/docs/architecture/psa-migration/psa-limitations.md
@@ -11,11 +11,15 @@
Limitations relevant for G1 (performing crypto operations)
==========================================================
-Restartable ECC operations
---------------------------
+Restartable (aka interruptible) ECC operations
+----------------------------------------------
-There is currently no support for that in PSA at all, but it will be added at
-some point, see <https://github.com/orgs/Mbed-TLS/projects/1#column-18816849>.
+Support for interruptible ECDSA sign/verify was added to PSA in Mbed TLS 3.4.
+However support for interruptible ECDH is not present yet. Also, PK, X.509 and
+TLS have not yet been adapted to take advantage of the new PSA APIs. See:
+- <https://github.com/Mbed-TLS/mbedtls/issues/7292>;
+- <https://github.com/Mbed-TLS/mbedtls/issues/7293>;
+- <https://github.com/Mbed-TLS/mbedtls/issues/7294>.
Currently, when `MBEDTLS_USE_PSA_CRYPTO` and `MBEDTLS_ECP_RESTARTABLE` are
both enabled, some operations that should be restartable are not (ECDH in TLS
@@ -78,6 +82,10 @@
migration by implementing RFC 7919. (Implementing RFC 7919 could be done any
time; making it mandatory can only be done in 4.0 or another major version.)
+As of early 2023, the plan is to go with option 2 in Mbed TLS 4.0, which has
+been announced on the mailing-list and got no push-back, see
+<https://github.com/Mbed-TLS/mbedtls/issues/5278>.
+
RSA-PSS parameters
------------------
@@ -321,6 +329,8 @@
in the meantime. Such an extension seems inconvenient and not motivated by
strong security arguments, so it's unclear whether it would be accepted.
+Since Mbed TLS 3.4, option 1 is implemented.
+
Limitations relevant for G2 (isolation of long-term secrets)
============================================================