Move the WSC Primary Device Type parsing from p2p.c and eap-wsc.c to a
common function in wscutil.c supporting both formats so that it can be
used in ap.c too.
The device type category array is indexed by the category ID so if we're
skipping i == 0 in the iteration, we should also skip the 0'th element
in device_type_categories.
Add the wfa_build_authorized_macs function (wfa_ prefix following the
wfa_extract_ naming) and use it in wsc_build_probe_response. The logic
is changed slightly to treat the first 6-zeros address in the array as
the end of the array.
wsc_attr_builder_start_attr and wsc_attr_builder_free look at
builder->curlen to see whether the TLV's length needs to be updated to
include the previous attribute. If builder->curlen is 0
wsc_attr_builder_start_attr assumes there's no previous attribute and
starts writing at current builder->offset. If the previous attribute
length was 0 curlen would stay at 0 and that attribute would get
overwritten with the new one. To solve this add the 4 bytes of the T
and L to curlen as soon as a new attribute is started, and subtract
them when writing the L value. The alternative would be to set a flag
to say whether an attribute was started.
The spec explicitly allows 0-length attributes in section 12:
"The variable length string attributes, e.g., Device Name, are encoded
without null-termination, i.e., no 0x00 octets added to the end of the
value. If the string is empty, the attribute length is set to zero."
Add a utility for building the simplified WSC IEs used in P2P action
frames and public action frames. Only three types of WSC attributes are
mandatory in those frames (but different subsets are needed by different
frame types) so add a single utility for building those IEs. We may
need to add some more optional attributes to those IEs later.
clang complains about enum as var_arg type
because of the argument standard conversion.
In a small test I did neither clang nor gcc can
properly warn about out of range values, so it's
purely for documentation either way.
==5362== Conditional jump or move depends on uninitialised value(s)
==5362== at 0x419B62: wsc_wfa_ext_iter_next (wscutil.c:52)
==5362== by 0x41B869: wsc_parse_probe_response (wscutil.c:1016)
==5362== by 0x41FD77: scan_results (wsc.c:218)
==5362== by 0x415669: get_scan_done (scan.c:892)
==5362== by 0x432932: destroy_request (genl.c:134)
==5362== by 0x433245: process_unicast (genl.c:394)
==5362== by 0x43361A: received_data (genl.c:506)
==5362== by 0x42FDC2: io_callback (io.c:120)
==5362== by 0x42EABE: l_main_run (main.c:381)
==5362== by 0x402F90: main (main.c:234)
Encrypted Settings TLVs are structured similarly to the various WSC
messages. However, they lack a version2 extension field and use a Key
Wrap Authenticator element instead of Authenticator.
