Clarify how key creation functions use attributes. Explain the meaning
of attribute values, espcially what 0 means in each field where it has
a special meaning. Explain what an algorithm usage policy can be (an
algorithm, a wildcard with ANY_HASH, or 0).
* open output distinct key handles
* each handle must be closed
* destroying a key does not invalidate other handles
* closing a key can/might fail an active operation (but not required)
It may be possible that the implementation runs out of
memory when exporting a key from storage or a secure
element. For example, it may not be possible to directly
move the data from storage to the caller, so the implementation
will have to buffer the material temporarily (an issue if dynamic
memory allocation scheme is used). For a large key
this is more likely to return.
It may be possible that an implementation does not
fetch key material until a command like
this is called and such an error may occur if an
off-chip secure storage dependency may have been wiped.
Note that PSA_ERROR_NOT_PERMITTED is not included
because I can't think of a scenario where you have
a valid key handle but aren't allowed to read the
attributes
If the key doesn't exist by the time this call is made
then the handle is invalid,
which means that PSA_ERROR_INVALID_HANDLE should be
returned rather than "does not exist"
It may be possible that the implementation runs out of
memory when exporting a key from storage or a secure
element. For example, it may not be possible to directly
move the data from storage to the caller, so the implementation
will have to buffer the material temporarily (an issue if dynamic
memory allocation scheme is used). For a large key
this is more likely to return.
It may be possible that an implementation does not
fetch key material until a command like
this is called and such an error may occur if an
off-chip secure storage dependency may have been wiped.
Note that PSA_ERROR_NOT_PERMITTED is not included
because I can't think of a scenario where you have
a valid key handle but aren't allowed to read the
attributes
Adjust the wording to permit multiple handles to a single key - closing
a handle does not necessarily release volatile memory associated with
the key, that only occurs when the last handle is closed.
- Describe the implementation defined behavior for opening multiple
keys, and provide a reference to the relevant section.
- Describe the use of INSUFFICENT_MEMORY error to indicate additional
implementation resource constaints.
- Clarify the distinction between DOES_NOT_EXIST and INVALID_HANDLE
error conditions.
PSA_KEY_ATTRIBUTES_INIT and psa_key_attributes_init weren't declared
in the API document, only defined in our implementation, but they are
referenced in the API document.
generate_key is a more classical name. The longer name was only
introduced to avoid confusion with getting a key from a generator,
which is key derivation, but we no longer use the generator
terminology so this reason no longer applies.
perl -i -pe 's/psa_generate_random_key/psa_generate_key/g' $(git ls-files)
“Tampering detected” was misleading because in the real world it can
also arise due to a software bug. “Corruption detected” is neutral and
more precisely reflects what can trigger the error.
perl -i -pe 's/PSA_ERROR_TAMPERING_DETECTED/PSA_ERROR_CORRUPTION_DETECTED/gi' $(git ls-files)
Parametrize finite-field Diffie-Hellman key types with a DH group
identifier, in the same way elliptic curve keys are parametrized with
an EC curve identifier.
Define the DH groups from the TLS registry (these are the groups from
RFC 7919).
Replicate the macro definitions and the metadata tests from elliptic
curve identifiers to DH group identifiers.
Define PSA_DH_GROUP_CUSTOM as an implementation-specific extension for
which domain parameters are used to specify the group.
Move psa_get_key_domain_parameters() and
psa_set_key_domain_parameters() out of the official API and declare
them to be implementation-specific extensions.
Expand the documentation of psa_set_key_domain_parameters() a bit to
explain how domain parameters are used.
Remove all mentions of domain parameters from the documentation of API
functions. This leaves DH and DSA effectively unusable.
Generators are mostly about key derivation (currently: only about key
derivation). "Generator" is not a commonly used term in cryptography.
So favor "derivation" as terminology.
This commit updates the function descriptions.
