While the TPM expects and returns the data in big-endian, the SAPI
implementation converts it to native-endianness. As stated in the
SAPI specification (section 3.2):
8. All SAPI data SHALL be in native-endian format. This means that
the SAPI implementation will do any endian conversion required for
both inputs and outputs.
So to use the exponent in a chunk we have to convert it to big-endian again.
Fixes: 7533cedb9a ("libtpmtss: Read RSA public key exponent instead of assuming its value")
RFC 7296, section 2.21.3:
If a peer parsing a request notices that it is badly formatted (after
it has passed the message authentication code checks and window
checks) and it returns an INVALID_SYNTAX notification, then this
error notification is considered fatal in both peers, meaning that
the IKE SA is deleted without needing an explicit Delete payload.
RFC 7296, section 2.21.3:
If a peer parsing a request notices that it is badly formatted (after
it has passed the message authentication code checks and window
checks) and it returns an INVALID_SYNTAX notification, then this
error notification is considered fatal in both peers, meaning that
the IKE SA is deleted without needing an explicit Delete payload.
This happened when installing a duplicate bypass policy for a locally
connected subnet. The destructor and the kernel-net part already
handle this correctly.
Without this we only would learn that the algorithm isn't actually
available (e.g. due to FIPS mode) when set_key() is called later, so there
isn't any automatic fallback to other implementations.
Fixes#3284.
Enforcing CA based constraints previously required the CA certificate file
to be locally installed. This is problematic from a maintencance perspective
when having many intermediate CAs, and is actually redundant if the client
sends its intermediate cert in the request.
The alternative was to use Distinguished Name matching in the subject
identity to indirectly check for the issuing CA by some RDN field, such as OU.
However, this requires trust in the intermediate CA to issue only certificates
with legitime subject identities.
This new approach checks for an intermediate CA by comparing the issuing
identity. This does not require trust in the intermediate, as long as
a path len constraint prevents that intermediate to issue further
intermediate certificates.
This avoids having to register certificates with authority/ca backends
beforehand, which is tricky for intermediate CA certificates loaded
themselves via authority/ca sections. On the other hand, the form of
these URLs can't be determined by config backends anymore (not an issue
for the two current implementations, no idea if custom implementations
ever made use of that possibility). If that became necessary, we could
perhaps pass the certificate to the CDP enumerator or add a new method
to the credential_set_t interface.
Don't define structs for macOS as we don't need them (that's true for
most of the others too, though) and at least one is defined inside an extra
ifdef.
If strings are missing (e.g. because the last value of a range changed
unknowingly or adding a string was simply forgotten) compilation will
now fail.
This could be problematic if the upper limit is out of our control (e.g.
from a system header like pfkeyv2.h), in which case patches might be
required on certain platforms (enforcing at least, and not exactly, the
required number of strings might also be an option to compile against
older versions of such a header - for internal enums it's obviously
better to enforce an exact match, though).
Tobias Brunner