Under WPA3-Personal, SAE authentication is used to derive PMK
which is more secure and immune to offline dictionary attacks.
1. Add modules to generate SAE commit/confirm for the handshake
2. Add modules that build and parse SAE data in Auth frames
3. Add WPA3 association and key mgmt definitions
4. Invert y-bit while solving for ECC co-ordinate -
Once an X co-ordinate is obtained, solving for Y co-ordinate
using an elliptical curve equation results in 2 possible values,
Y and (P - Y), where p is the prime number. The co-ordinates are
used for deriving keys in SAE handshake. As par the 802.11 spec
if LSB of X is same as LSB of Y then Y is chosen, (P - Y) otherwise.
This is not what is implemented, so fix this behavior to obtain the
correct Y co-ordinate.
This change ports SAE(Simultaneous Authentication of Equals)
feature from wpa_supplicant and makes it work with mbedtls
crypto APIs. Currently only group 19 is supported. A sample
SAE handshake is included in the testcase. Other minor
changes for DH groups are also included.
