SIM card related Projects » pySim

Just a quick observation:

sysmoISIM-SJA2 has Services 123 (5G Security Parameters) & 124 set by default but no EF_5G_Auth_Keys and EF_SUCI_Calc_Info files present. My Qualcomm modems don't fall back to IMSI then but instead show a USIM failure and apparently stop searching/connecting anything 5G.

So either disabling the services or writing the files is a must with these modems and 5G-SA.

I've added the following code in pySim-read, just after USIM initialization (I'm not very familiar with SIM, want to make sure I'm in the right… directory?)

    # Check whether we have th AID of USIM, if so select it by its AID
    # EF.UST - File Id in ADF USIM : 6f38
    if '9000' == card.select_adf_by_aid():
        # Select USIM profile
        usim_card = UsimCard(scc)

        print("EF_UST available (just to check): %s" % str(usim_card.file_exists('6F38')))
        print("EF_SUCI_Calc_Info available: %s" % str(usim_card.file_exists('4F07')))
        print("EF_5G_Auth_Keys available: %s" % str(usim_card.file_exists('4F05')))

        (res, sw) = card.read_binary('6F38')
        if sw == '9000':
            print("EF_UST: %s" % res)
        else:
            print("EF_UST: Can't read, response code = %s" % (sw,))

        (res, sw) = card.read_binary('4F07')
        if sw == '9000':
            print("EF_SUCI_Calc_Info: %s" % res)
        else:
            print("EF_SUCI_Calc_Info: Can't read, response code = %s" % (sw,))

        (res, sw) = card.read_binary('4F05')
        if sw == '9000':
            print("EF_5G_Auth_Keys: %s" % res)
        else:
            print("EF_5G_Auth_Keys: Can't read, response code = %s" % (sw,))

Output:

Using PC/SC reader interface
Reading ...
Autodetected card type: sysmoISIM-SJA2
ICCID: 8988211000000448822
...
EF_UST available (just to check): True
EF_SUCI_Calc_Info available: False
EF_5G_Auth_Keys available: False
EF_UST: beff9f9de73e0408400170330000000000000000
Traceback (most recent call last):
  File "./pySim-read.py", line 267, in <module>
    (res, sw) = card.read_binary('4F07')
  File "/home/merlin/tools/pysim/pySim/cards.py", line 189, in read_binary
    return self._scc.read_binary(ef_path, length, offset)
  File "/home/merlin/tools/pysim/pySim/commands.py", line 128, in read_binary
    r = self.select_file(ef)
  File "/home/merlin/tools/pysim/pySim/commands.py", line 119, in select_file
    data, sw = self._tp.send_apdu_checksw(self.cla_byte + "a4" + self.sel_ctrl + "02" + i)
  File "/home/merlin/tools/pysim/pySim/transport/__init__.py", line 104, in send_apdu_checksw
    raise RuntimeError("SW match failed! Expected %s and got %s." % (sw.lower(), rv[1]))
RuntimeError: SW match failed! Expected 9000 and got 6a82.

I've played with the MS Operation Mode as well but besides the card is pretty fresh.

Thanks a lot, the files are there of course.

For anybody googling this, I read ADF.USIM/DF.5GS like this: https://github.com/mrlnc/pysim/commit/c7f9afeeeb43dd4f62ced3f1c63aa21983fcdb24
and updated the UST with something like this in SysmoISIMSJA2.program():

        print("Disabling 5G Security Parameters")
        ust_5g = [122, 123, 124, 126]
        for service in ust_5g:
            sw = self.update_ust(service, 0)
            if sw != '9000':
                print("Disabling 5G Service %i failed with code %s"% (service, sw))

• scheme (profile A or B)
• key identifier (currently hardcoded & limited to 1 byte)
• key
• priority in some way

My WIP branch is here: https://github.com/mrlnc/pysim/tree/wip-suci

Right now the identifiers & file order are hardcoded to replicate the test file from TS31.121 4.9.4. Changing priority works as expected and is accepted by the modem.

I'll check out the pySim-shell first.

pysim-shell is pretty cool! I integrated SUCI-Calc-Info: https://github.com/mrlnc/pysim/tree/wip-shell-suci

• Encode + Write
• Read + Decode
• Testcase replicating the example file from

I take the JSON input to encode the file; what would be the right place for documentation of the format?

pySIM-shell (MF)> select ADF.USIM
pySIM-shell (MF/ADF.USIM)> select DF.5GS 
pySIM-shell (MF/ADF.USIM/DF.5GS)> select EF.SUCI_Calc_Info 
pySIM-shell (MF/ADF.USIM/DF.5GS/EF.SUCI_Calc_Info)> update_binary_decoded '{"prot_scheme_id_list": [{"priority": 0, "identifier": 2, "key_index": 1}, {"priority": 1, "identifier": 1, "key_index": 2}, {"priority": 2, "identifier": 0, "key_index": 0}], "hnet_pubkey_list": [{"hnet_pubkey_identifier": 27, "hnet_pubkey": "0272da71976234ce833a6907425867b82e074d44ef907dfb4b3e21c1c2256ebcd1"}, {"hnet_pubkey_identifier": 30, "hnet_pubkey": "5a8d38864820197c3394b92613b20b91633cbd897119273bf8e4a6f4eec0a650"}]}
pySIM-shell (MF/ADF.USIM/DF.5GS/EF.SUCI_Calc_Info)> read_binary_decoded
9000: a006020101020000a14b80011b81210272da71976234ce833a6907425867b82e074d44ef907dfb4b3e21c1c2256ebcd180011e81205a8d38864820197c3394b92613b20b91633cbd897119273bf8e4a6f4eec0a650a650ffffffffffffffffffffffffff -> {'prot_scheme_id_list': [{'priority': 0, 'identifier': 2, 'key_index': 1}, {'priority': 1, 'identifier': 1, 'key_index': 2}, {'priority': 2, 'identifier': 0, 'key_index': 0}], 'hnet_pubkey_list': [{'hnet_pubkey_identifier': 27, 'hnet_pubkey': '0272da71976234ce833a6907425867b82e074d44ef907dfb4b3e21c1c2256ebcd1'}, {'hnet_pubkey_identifier': 30, 'hnet_pubkey': '5a8d38864820197c3394b92613b20b91633cbd897119273bf8e4a6f4eec0a650'}]}
{
    "prot_scheme_id_list": [
        {
            "priority": 0,
            "identifier": 2,
            "key_index": 1
        },
        {
            "priority": 1,
            "identifier": 1,
            "key_index": 2
        },
        {
            "priority": 2,
            "identifier": 0,
            "key_index": 0
        }
    ],
    "hnet_pubkey_list": [
        {
            "hnet_pubkey_identifier": 27,
            "hnet_pubkey": "0272da71976234ce833a6907425867b82e074d44ef907dfb4b3e21c1c2256ebcd1" 
        },
        {
            "hnet_pubkey_identifier": 30,
            "hnet_pubkey": "5a8d38864820197c3394b92613b20b91633cbd897119273bf8e4a6f4eec0a650" 
        }
    ]
}

Export still fails; maybe I didn't register the directory correctly?
Output:

################################################################################
# MF/ADF.USIM/DF.5GS/EF.5GS3GPPLOCI                                            #
################################################################################
# directory: MF/ADF.USIM/DF.5GS (3f00/a0000000871002/5fc0)
# file: EF.5GS3GPPLOCI (4f01)
# bad file: MF/ADF.USIM/DF.5GS/EF.5GS3GPPLOCI/EF.5GS3GPPLOCI, string indices must be integers
#
################################################################################
# MF/ADF.USIM/DF.5GS/EF.5GS3GPPLOCI/EF.5GSN3GPPLOCI                            #
################################################################################
# directory: MF/ADF.USIM/DF.5GS/EF.5GS3GPPLOCI (3f00/a0000000871002/5fc0/4f01)
# file: EF.5GSN3GPPLOCI (4f02)
# bad file: MF/ADF.USIM/DF.5GS/EF.5GSN3GPPLOCI/EF.5GSN3GPPLOCI, string indices must be integers

merlinchlosta wrote:

pysim-shell is pretty cool! I integrated SUCI-Calc-Info: https://github.com/mrlnc/pysim/tree/wip-shell-suci

happy to hear you like it.

I take the JSON input to encode the file; what would be the right place for documentation of the format?

Unfortunately we haven't yet figured that out. I'm not sure what kind of frameworks would exist in python to help us with documentation. Ideally the documentation would be written in-line next to the code (less chance to go out of date), and then extracted into some kind of spec/reference document.

Export still fails; maybe I didn't register the directory correctly?

I've assigned this ticket to dexter who wrote the export, maybe he can help.

applied your comments from github, gerrit PR: https://gerrit.osmocom.org/c/pysim/+/23564

Export works as expected since you removed the DF.5GS decode_select_response() in commit 082d4e095688df3cbbb8675e4bf4bdade6a28d14.

Hello merlinchlosta,

thanks for contributing to pySim-shell. I see your patch got merged some time ago. I have now tested (decoded) reading and writing of EF_UST and ADF_USIM/EF_SUCI_Calc_Info and as far as I can tell it works fine. So I think we can close this ticket now.

Best regards.
Philipp