personalization: fix SdKey.apply_val() implementation

'securityDomain' elements are decoded to ProfileElementSD instances,
which keep higher level representations of the key data apart from the
decoded[] lists.

So far, apply_val() was dropping binary values in decoded[], which does
not work, because ProfileElementSD._pre_encode() overwrites
self.decoded[] from the higher level representation.

Implement using
- ProfileElementSD.find_key() and SecurityDomainKeyComponent to modify
  an exsiting entry, or
- ProfileElementSD.add_key() to create a new entry.

Before this patch, SdKey parameters seemed to patch PES successfully,
but their modifications did not end up in the encoded DER.

(BTW, this does not fix any other errors that may still be present in
the various SdKey subclasses, patches coming up.)

Related: SYS#6768
Change-Id: I07dfc378705eba1318e9e8652796cbde106c6a52
This commit is contained in:
Neels Hofmeyr
2025-03-01 01:36:27 +01:00
parent eca2fd39c0
commit 8fb451b732
2 changed files with 41 additions and 28 deletions

View File

@@ -1071,6 +1071,13 @@ class SecurityDomainKey:
'keyVersionNumber': bytes([self.key_version_number]),
'keyComponents': [k.to_saip_dict() for k in self.key_components]}
def get_key_component(self, key_type):
for kc in self.key_components:
if kc.key_type == key_type:
return kc.key_data
return None
class ProfileElementSD(ProfileElement):
"""Class representing a securityDomain ProfileElement."""
type = 'securityDomain'

View File

@@ -24,9 +24,11 @@ from typing import List, Tuple, Generator, Optional
from osmocom.tlv import camel_to_snake
from osmocom.utils import hexstr
from pySim.utils import enc_iccid, dec_iccid, enc_imsi, dec_imsi, h2b, b2h, rpad, sanitize_iccid
from pySim.esim.saip import ProfileElement, ProfileElementSequence
from pySim.esim.saip import param_source
from pySim.ts_51_011 import EF_SMSP
from pySim.esim.saip import param_source
from pySim.esim.saip import ProfileElement, ProfileElementSD, ProfileElementSequence
from pySim.esim.saip import SecurityDomainKey, SecurityDomainKeyComponent
from pySim.global_platform import KeyUsageQualifier, KeyType
def unrpad(s: hexstr, c='f') -> hexstr:
return hexstr(s.rstrip(c))
@@ -591,36 +593,40 @@ class SdKey(BinaryParam, metaclass=ClassVarMeta):
key_usage_qual = None
@classmethod
def _apply_sd(cls, pe: ProfileElement, value):
assert pe.type == 'securityDomain'
for key in pe.decoded['keyList']:
if key['keyIdentifier'][0] == cls.key_id and key['keyVersionNumber'][0] == cls.kvn:
assert len(key['keyComponents']) == 1
key['keyComponents'][0]['keyData'] = value
return
# Could not find matching key to patch, create a new one
key = {
'keyUsageQualifier': bytes([cls.key_usage_qual]),
'keyIdentifier': bytes([cls.key_id]),
'keyVersionNumber': bytes([cls.kvn]),
'keyComponents': [
{ 'keyType': bytes([cls.key_type]), 'keyData': value },
]
}
pe.decoded['keyList'].append(key)
def apply_val(cls, pes: ProfileElementSequence, val):
set_components = [ SecurityDomainKeyComponent(cls.key_type, val) ]
@classmethod
def apply_val(cls, pes: ProfileElementSequence, value):
for pe in pes.get_pes_for_type('securityDomain'):
cls._apply_sd(pe, value)
for pe in pes.pe_list:
if pe.type != 'securityDomain':
continue
assert isinstance(pe, ProfileElementSD)
key = pe.find_key(key_version_number=cls.kvn, key_id=cls.key_id)
if not key:
# Could not find matching key to patch, create a new one
key = SecurityDomainKey(
key_version_number=cls.kvn,
key_id=cls.key_id,
key_usage_qualifier=KeyUsageQualifier.build(cls.key_usage_qual),
key_components=set_components,
)
pe.add_key(key)
else:
key.key_components = set_components
@classmethod
def get_values_from_pes(cls, pes: ProfileElementSequence):
for pe in pes.get_pes_for_type('securityDomain'):
for key in pe.decoded['keyList']:
if key['keyIdentifier'][0] == cls.key_id and key['keyVersionNumber'][0] == cls.kvn:
if len(key['keyComponents']) >= 1:
yield { cls.name: b2h(key['keyComponents'][0]['keyData']) }
for pe in pes.pe_list:
if pe.type != 'securityDomain':
continue
assert isinstance(pe, ProfileElementSD)
key = pe.find_key(key_version_number=cls.kvn, key_id=cls.key_id)
if not key:
continue
kc = key.get_key_component(cls.key_type)
if kc:
yield { cls.name: b2h(kc) }
class SdKeyScp80_01(SdKey, kvn=0x01, key_type=0x88, permitted_len=[16,24,32]): # AES key type
pass