I extracted the 294 bytes (those which start with `30 82 01 22 30`

). To recap, the bytes are found inside the *secio* handshake. The handshake is protobuf serialized *Propose* with 5 fields, of which the field *pubkey* ID=2 is again protobuf serialized *PublicKey* with 2 fields, of which the field with again ID=2 contains the public key in *DER format*.

Graphically:

`Response -> {nonce, pubkey -> PublicKey {KeyType, Data}, exchanges, ciphers, hashes }`

Once you save these bytes to for example `publickey.der`

, then you can run openssl to check if you exctracted correctly the public key data.

You do it by invoking the following command to CLI:

`openssl rsa -text -inform DER -in publickey.der -pubin`

For example, I’m giving what I got (you’ll get of course something else):

`Public-Key: (2048 bit) Modulus: 00:99:00:93:c8:b3:23:f8:19:31:2a:c6:08:07:1e: 97:ff:09:f3:76:f9:eb:86:28:c0:86:5f:54:53:8f: e3:a7:65:28:a6:51:43:42:7e:73:cb:0f:3f:1c:7a: 96:2f:32:ef:1a:91:7a:b0:48:1b:d9:94:05:88:dd: 95:f9:fb:70:91:2d:71:82:80:99:54:68:70:0d:e7: 12:ef:bd:65:de:7f:38:94:b8:74:e5:49:8c:1b:8c: da:ef:6b:6d:c2:56:92:a3:6c:0a:56:30:26:d3:ad: 07:87:37:a4:33:11:a0:83:65:85:5a:ca:f8:8a:1e: cf:63:7f:e0:19:92:cc:e0:00:01:29:5d:eb:9f:9f: cd:a1:fb:5d:ca:9a:26:70:7f:98:84:95:a7:0c:0f: 39:bf:ff:f6:ee:42:a5:b9:4d:01:6a:3a:d1:1a:61: ad:cb:5b:69:a5:c0:22:a2:c4:d5:4d:17:94:da:d7: d3:fa:4b:6f:aa:c8:d5:09:eb:c7:85:cd:2d:fb:19: a1:1d:75:49:7a:37:5f:b8:fc:68:b6:79:b1:39:b5: 1a:81:35:a7:07:b4:aa:0d:c1:b7:17:0c:cc:df:b2: 2d:e3:6e:b4:a0:a8:17:58:c6:bd:c4:13:b5:dc:c0: 23:8a:2e:d1:35:4f:bb:26:d1:a6:f6:c0:0c:45:5c: 0a:d5 Exponent: 65537 (0x10001) writing RSA key -----BEGIN PUBLIC KEY----- MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAmQCTyLMj+BkxKsYIBx6X /wnzdvnrhijAhl9UU4/jp2UoplFDQn5zyw8/HHqWLzLvGpF6sEgb2ZQFiN2V+ftw kS1xgoCZVGhwDecS771l3n84lLh05UmMG4za72ttwlaSo2wKVjAm060HhzekMxGg g2WFWsr4ih7PY3/gGZLM4AABKV3rn5/NoftdypomcH+YhJWnDA85v//27kKluU0B ajrRGmGty1tppcAiosTVTReU2tfT+ktvqsjVCevHhc0t+xmhHXVJejdfuPxotnmx ObUagTWnB7SqDcG3FwzM37It4260oKgXWMa9xBO13MAjii7RNU+7JtGm9sAMRVwK 1QIDAQAB -----END PUBLIC KEY-----`