[BitBucket user: Sébastien Jodogne]
[BitBucket date: 2017-07-18.15:46:35]

The philosophy of Orthanc consists in making configuration as simple as possible for basic use cases. I have therefore added [two new security-related configuration options](https://hg.orthanc-server.com/orthanc/raw-file/default/Resources/Configuration.json) to solve this issue: `DicomAlwaysAllowStore` and `DicomCheckModalityHost`. The former forbids C-Store from unknown modalities, the second checks the IP address of the remote modality.

Here is a sample, minimalist configuration file illustrating those 2 options:

``` json
{
  "DicomCheckCalledAet" : true,
  "DicomModalities" : {
    "peer" : [ "PEER", "127.0.0.1", 2000 ],
    "peer2" : [ "BAD_IP", "1.1.1.1", 2000 ]
  },
  "DicomAlwaysAllowStore" : false,
  "DicomCheckModalityHost" : true
}
```

Here is now an interactive session (run from the localhost `127.0.0.1`) that shows how the security now works as you initially expected:

``` text
$ echoscu -aec ORTHANC -aet PEER localhost 4242 -v 2>&1 | tail -n2
I: Received Echo Response (Success)
I: Releasing Association

$ echoscu -aec ORTHANC -aet BAD_AET localhost 4242 -v 2>&1 | tail -n2
E: Echo Failed: 0006:0317 Peer aborted Association (or never connected)
I: Peer Aborted Association

$ echoscu -aec ORTHANC -aet BAD_IP localhost 4242 -v 2>&1 | tail -n2
E: Echo Failed: 0006:0317 Peer aborted Association (or never connected)
I: Peer Aborted Association

$ findscu -S -k QueryRetrieveLevel=STUDY -aec ORTHANC -aet PEER localhost 4242 -v 2>&1 | tail -n2
I: Received Final Find Response (Success)
I: Releasing Association

$ findscu -S -k QueryRetrieveLevel=STUDY -aec ORTHANC -aet BAD_AET localhost 4242 -v 2>&1 | tail -n2
E: 0006:0317 Peer aborted Association (or never connected)
I: Peer Aborted Association

$ findscu -S -k QueryRetrieveLevel=STUDY -aec ORTHANC -aet BAD_IP localhost 4242 -v 2>&1 | tail -n2
E: 0006:0317 Peer aborted Association (or never connected)
I: Peer Aborted Association

$ storescu localhost 4242 /tmp/xr_hands.dcm -aec ORTHANC -aet PEER -v 2>&1 | tail -n2
I: Received Store Response (Success)
I: Releasing Association

$ storescu localhost 4242 /tmp/xr_hands.dcm -aec ORTHANC -aet BAD_AET -v 2>&1 | tail -n2
I: Aborting Association
E: Association Abort Failed: 0006:031d TCP I/O Error (Broken pipe) occurred in routine: sendAbortTCP

$ storescu localhost 4242 /tmp/xr_hands.dcm -aec ORTHANC -aet BAD_IP -v 2>&1 | tail -n2
I: Aborting Association
E: Association Abort Failed: 0006:031d TCP I/O Error (Broken pipe) occurred in routine: sendAbortTCP
```

The log file of Orthanc shows that `BAD_AET` and `BAD_IP` are treated differently:

```
W0718 17:43:13.212854 OrthancInitialization.cpp:865] Modality "BAD_AET" is not listed in the "DicomModalities" configuration option
W0718 17:43:13.212882 CommandDispatcher.cpp:812] Rejected Echo request from remote DICOM modality with AET "BAD_AET" and hostname "127.0.0.1"
W0718 17:43:14.458409 OrthancInitialization.cpp:876] Forbidding access from AET "BAD_IP" given its hostname (127.0.0.1) does not match the "DicomModalities" configuration option (1.1.1.1 was expected)
W0718 17:43:14.458440 CommandDispatcher.cpp:812] Rejected Echo request from remote DICOM modality with AET "BAD_IP" and hostname "127.0.0.1"
```