Implement DTLS 1.2 Connection ID (CID)

[julek-wolfssl]

No description provided.

[julek-wolfssl]

Retest this please.

[rizlik]

I like the refactor of doing ETM MAC size calculation in a single place, but I found the re-use of keys.PadSz a little misleading. Can you think of a re-name or using an extra variable?

[julek-wolfssl]

keys.PadSz is used in a lot of places and I don't want to change that here. If you really want a new name I would propose to do it in a new PR.

[rizlik]

Ok, LGTM

[JacobBarthelmeh]

I'd like to have one more person review this pull request too.

When trying to build using the configure :./configure --enable-dtls --enable-dtlscid --enable-dtls13

tests/api.c:94360:25: error: implicit declaration of function ‘wolfSSL_Rehandshake’; did you mean ‘wolfSSL_BIO_do_handshake’? [-Werror=implicit-function-declaration]
94360 |             ExpectIntEQ(wolfSSL_Rehandshake(ssl_c), -1);
      |                         ^~~~~~~~~~~~~~~~~~~
./tests/unit.h:188:24: note: in definition of macro ‘ExpectInt’

Adding secure-renegotiation ./configure --enable-dtls --enable-dtlscid --enable-dtls13 --enable-secure-renegotiation results in :

   911: test_dtls_old_seq_number                            : passed (  0.00351)
   912: test_dtls12_basic_connection_id                     :
Testing AES128-SHA256 run #0 ... 
ERROR - tests/api.c line 94241 failed with:
    expected: wolfSSL_set_cipher_list(ssl_c, params[i]) == 1
    result:   0 != 1

failed
Testing AES128-SHA256 run #1 ... failed

[rizlik]

retest this please

[JacobBarthelmeh]

@SparkiDev please give this an additional review.

[SparkiDev]

'hash' may not have been initialised properly.
It' looks fine with the implementation but don't rely on that.

[SparkiDev]

Ran timing test of TLS_hmac and appears fine.