osmo-smdpp: Support multiple different profiles

Let's simply use the matchingId for filesystem lookup of the UPP file.

This way we can have any number of profiles by simply creating the
respeective files.

Change-Id: I0bc3a14b9fdfcc6322917dd0c69d8295de486950

docs/osmo-smdpp.rst

@@ -21,8 +21,9 @@ osmo-smdpp currently
 
 * uses test certificates copied from GSMA SGP.26 into `./smdpp-data/certs`, assuming that your osmo-smdppp
   would be running at the host name `testsmdpplus1.example.com`
-* always provides the exact same profile to every request.  The profile always has the same IMSI and
-  ICCID.
+* doesn't understand profile state. Any profile can always be downloaded any number of times, irrespective
+  of the EID or whether it was donwloaded before
+* doesn't perform any personalization, so the IMSI/ICCID etc. are always identical
 * **is absolutely insecure**, as it
 
  * does not perform any certificate verification
@@ -83,7 +84,8 @@ and it will bind its plain-HTTP ES9+ interface to local TCP port 8000.
 The `smdpp-data/certs`` directory contains the DPtls, DPauth and DPpb as well as CI certificates
 used; they are copied from GSMA SGP.26 v2.
 
-The `smdpp-data/upp` directory contains the UPP (Unprotected Profile Package) used.
+The `smdpp-data/upp` directory contains the UPP (Unprotected Profile Package) used.  The file names (without
+.der suffix) are looked up by the matchingID parameter from the activation code presented by the LPA.
 
 
 DNS setup for your LPA

osmo-smdpp.py

@@ -135,6 +135,7 @@ class SmDppHttpServer:
 
     def __init__(self, server_hostname: str, ci_certs_path: str, use_brainpool: bool = False):
         self.server_hostname = server_hostname
+        self.upp_dir = os.path.realpath(os.path.join(DATA_DIR, 'upp'))
         self.ci_certs = self.load_certs_from_path(ci_certs_path)
         # load DPauth cert + key
         self.dp_auth = CertAndPrivkey(oid.id_rspRole_dp_auth_v2)
@@ -344,6 +345,27 @@ class SmDppHttpServer:
         if euiccSigned1['serverChallenge'] != ss.serverChallenge:
             raise ApiError('8.1', '6.1', 'Verification failed')
 
+        # If ctxParams1 contains a ctxParamsForCommonAuthentication data object, the SM-DP+ Shall [...]
+        # TODO: We really do a very simplistic job here, this needs to be properly implemented later,
+        # considering all the various cases, profile state, etc.
+        if euiccSigned1['ctxParams1'][0] == 'ctxParamsForCommonAuthentication':
+            cpca = euiccSigned1['ctxParams1'][1]
+            matchingId = cpca.get('matchingId', None)
+            if not matchingId:
+                # TODO: check if any pending profile downloads for the EID
+                raise ApiError('8.2.6', '3.8', 'Refused')
+            if matchingId:
+                # look up profile based on matchingID.  We simply check if a given file exists for now..
+                path = os.path.join(self.upp_dir, matchingId) + '.der'
+                # prevent directory traversal attack
+                if os.path.commonprefix((os.path.realpath(path),self.upp_dir)) != self.upp_dir:
+                    raise ApiError('8.2.6', '3.8', 'Refused')
+                if not os.path.isfile(path) or not os.access(path, os.R_OK):
+                    raise ApiError('8.2.6', '3.8', 'Refused')
+                ss.matchingId = matchingId
+
+        # FIXME: we actually want to perform the profile binding herr, and read the profile metadat from the profile
+
         # Put together profileMetadata + _bin
         ss.profileMetadata = ProfileMetadata(iccid_bin= h2b(swap_nibbles('89000123456789012358')), spn="OsmocomSPN", profile_name="OsmocomProfile")
         profileMetadata_bin = ss.profileMetadata.gen_store_metadata_request()
@@ -425,7 +447,7 @@ class SmDppHttpServer:
         # TODO: Check if this order requires a Confirmation Code verification
 
         #  Perform actual protection + binding of profile package (or return  pre-bound one)
-        with open(os.path.join(DATA_DIR, 'upp', 'TS48 V2 eSIM_GTP_SAIP2.1_NoBERTLV.rename2der'), 'rb') as f:
+        with open(os.path.join(self.upp_dir, ss.matchingId)+'.der', 'rb') as f:
             upp = UnprotectedProfilePackage.from_der(f.read(), metadata=ss.profileMetadata)
             # HACK: Use empty PPP as we're still debuggin the configureISDP step, and we want to avoid
             # cluttering the log with stuff happening after the failure

tests/test_esim_saip.py

@@ -26,7 +26,7 @@ from pprint import pprint as pp
 
 
 class SaipTest(unittest.TestCase):
-    with open('smdpp-data/upp/TS48 V2 eSIM_GTP_SAIP2.3_NoBERTLV.rename2der', 'rb') as f:
+    with open('smdpp-data/upp/TS48v2_SAIP2.3_NoBERTLV.der', 'rb') as f:
         per_input = f.read()
     pes = ProfileElementSequence.from_der(per_input)
     expected_pet_list = ['header', 'mf', 'pukCodes', 'pinCodes', 'telecom', 'pinCodes', 'genericFileManagement', 'usim', 'opt-usim', 'pinCodes', 'akaParameter', 'gsm-access', 'df-5gs', 'df-saip','csim', 'opt-csim', 'pinCodes', 'cdmaParameter', 'isim', 'opt-isim', 'pinCodes', 'akaParameter', 'genericFileManagement', 'genericFileManagement', 'securityDomain', 'rfm', 'rfm', 'rfm', 'rfm', 'end']