Add remote_port in the audit logs when it is available

[remilapeyre]

The request.remote_port field is now present in the audit log when it
is available:

{
  "time": "2021-10-10T13:53:51.760039Z",
  "type": "response",
  "auth": {
    "client_token": "hmac-sha256:1304aab0ac65747684e1b58248cc16715fa8f558f8d27e90fcbcb213220c0edf",
    "accessor": "hmac-sha256:f8cf0601dadd19aac84f205ded44c62898e3746a42108a51105a92ccc39baa43",
    "display_name": "root",
    "policies": [
      "root"
    ],
    "token_policies": [
      "root"
    ],
    "token_type": "service",
    "token_issue_time": "2021-10-10T15:53:44+02:00"
  },
  "request": {
    "id": "829c04a1-0352-2d9d-9bc9-00b928d33df5",
    "operation": "update",
    "mount_type": "system",
    "client_token": "hmac-sha256:1304aab0ac65747684e1b58248cc16715fa8f558f8d27e90fcbcb213220c0edf",
    "client_token_accessor": "hmac-sha256:f8cf0601dadd19aac84f205ded44c62898e3746a42108a51105a92ccc39baa43",
    "namespace": {
      "id": "root"
    },
    "path": "sys/audit/file",
    "data": {
      "description": "hmac-sha256:321a1d105f8c6fd62be4f34c4da4f0e6d1cdee9eb2ff4af0b59e1410950fe86b",
      "local": false,
      "options": {
        "file_path": "hmac-sha256:2421b5bf8dab1f9775b2e6e66e58d7bca99ab729f3f311782fda50717eee55b3"
      },
      "type": "hmac-sha256:30dff9607b4087e3ae6808b4a3aa395b1fc064e467748c55c25ddf0e9b150fcc"
    },
    "remote_address": "127.0.0.1",
    "remote_port": 54798
  },
  "response": {
    "mount_type": "system"
  }
}

Closes #7716

[ccapurso]

Hi @remilapeyre, thank you for the contribution! This looks like an intriguing and useful addition to audit log entries. Would you be able to add a test that verifies that the remote port is included in the audit log entry? This will help us prevent regressions. To ensure consistency, a few scenarios we might want to test are:

• the remote host has a port and it is valid
• the remote host has a port but it is invalid
• the remote host does not have a port

Here is a recent example of a test that verifies audit log output based on a logical.Request that you might want to reference.

[remilapeyre]

Hi @remilapeyre, thank you for the contribution! This looks like an intriguing and useful addition to audit log entries. Would you be able to add a test that verifies that the remote port is included in the audit log entry? This will help us prevent regressions. To ensure consistency, a few scenarios we might want to test are:

* the remote host has a port and it is valid

* the remote host has a port but it is invalid

* the remote host does not have a port

Here is a recent example of a test that verifies audit log output based on a logical.Request that you might want to reference.

Hi @ccapurso, I updated the error handling and added a test for the happy case. I'm not sure how to test for when the port is invalid or missing since when using the test client it does not happen.

[ccapurso]

I have one very minor change request but otherwise this looks good to me.

[pmmukh]

Hi @remilapeyre ! Just dropping a reminder that Chris requested one more change on this PR, post which it should be good to merge !

[remilapeyre]

Thanks for the ping @pmmukh, it should all be good now!

[HridoyRoy]

Hi @remilapeyre , the PR looks really good! I have some small questions primarily about int types, but otherwise I'm happy to approve.

Thanks for the contribution!

[HridoyRoy]

After discussing and thinking through the int type questions a little more, I think everything looks great! Lgtm!

[remilapeyre]

After discussing and thinking through the int type questions a little more, I think everything looks great! Lgtm!

Thanks!