requirements: ensure safe version of PyYAML >= 5.4 (CVE-2020-1747)
PyYAML versions 5.1–5.3.1 are vulnerable to CVE-2020-1747, which allows arbitrary code execution through yaml.FullLoader. While PyYAML 5.4+ patches this, the dependency specification (pyyaml >= 5.1) doesn't guarantee a safe version. Let's increase the requirement to version 5.4 to ensure a safe version of is used.
This patch is based on suggestions from: "YanTong C <chyeyantong03@gmail.com>"
osmo-smdpp.py: fix path Traversal Bypass in SM-DP+ (CWE-22)
Root Cause: os.path.commonprefix() compares strings character-by-character, NOT by path components. This is a well-known Python antipattern (Python docs explicitly warn: "this function may return invalid paths because it works a character at a time").
Attack Context: The matchingId parameter is received from a network client via the GSMA ES9+ authenticateClient API endpoint (POST to /gsma/rsp2/es9plus/authenticateClient). The SM-DP+ server is a Twisted web application listening on port 443. An unauthenticated eUICC client sends the matchingId in the ctxParamsForCommonAuthentication ASN.1 structure.
Fix: Replace os.path.commonprefix() with proper path component checking:
requirements: ensure safe version of PyYAML >= 5.4 (CVE-2020-1747)
PyYAML versions 5.1–5.3.1 are vulnerable to CVE-2020-1747, which allows arbitrary code execution through yaml.FullLoader. While PyYAML 5.4+ patches this, the dependency specification (pyyaml >= 5.1) doesn't guarantee a safe version. Let's increase the requirement to version 5.4 to ensure a safe version of is used.
This patch is based on suggestions from: "YanTong C <chyeyantong03@gmail.com>"
pySim-prog: fix Insecure PRNG for SIM Authentication Keys (CWE-338)
Root Cause: pySim-prog.py uses Python's random module (Mersenne Twister MT19937) to generate Ki and OPC — the root authentication keys for SIM cards. MT19937 is a deterministic PRNG that is not cryptographically secure. Its internal state (624 × 32-bit words, 19,937 bits) can be fully recovered after observing 624 consecutive outputs.
Impact: 1. SIM Card Cloning: An attacker who determines the PRNG state can predict all Ki/OPC values generated before and after. With these keys, SIM cards can be cloned. 2. Network Authentication Bypass: Ki/OPC are used in the Milenage algorithm for 3G/4G/5G authentication. Predictable keys mean an attacker can authenticate as any subscriber whose SIM was provisioned with the weak RNG. 3. Batch Compromise: In bulk provisioning scenarios (pySim-prog's primary use case), hundreds or thousands of SIMs may be programmed sequentially. Compromising one batch means recovering the PRNG state to predict all keys.
The current behavior we implement in the method __send_apdu_T0 is incomplete. Some details discussed in ETSI TS 102 221, section 7.3.1.1.4, clause 4 seem to be not fully implemented. We may also end up sending a GET RESPONSE in other APDU cases than case 4 (the only case that uses the GET RESPONSE command).
The current behavior we implement in the method __send_apdu_T0 is incomplete. Some details discussed in ETSI TS 102 221, section 7.3.1.1.4, clause 4 seem to be not fully implemented. We may also end up sending a GET RESPONSE in other APDU cases than case 4 (the only case that uses the GET RESPONSE command).
The current behavior we implement in the method __send_apdu_T0 is incomplete. Some details discussed in ETSI TS 102 221, section 7.3.1.1.4, clause 4 seem to be not fully implemented. We may also end up sending a GET RESPONSE in other APDU cases than case 4 (the only case that uses the GET RESPONSE command).
filesystem: JsonEditor: offer interactive retry on error
When json.loads() fails (e.g. the user made a syntax mistake), prompt the user with "Re-open file for editing? [y]es/[n]o:" and loop back to the editor if they answer 'y' or 'yes'. If the user declines, return the original unmodified value so no write is attempted; the temp file is still cleaned up by __exit__() in that case.
tests: fix TransRecEF _test_de_encode to operate at file level
Previously, _test_de_encode vectors for TransRecEF subclasses were tested via decode_record_hex()/encode_record_hex(), i.e. one record at a time, with the decoded value being a scalar.
Switch test_de_encode_record() in TransRecEF_Test to use decode_hex() / encode_hex() instead, so that vectors represent whole-file content (decoded value is a list of records) -- consistent with how LinFixedEF handles _test_de_encode. Update all existing vectors accordingly.
A plain NamedTemporaryFile is sufficient here: we only need a single file, not a directory to hold it. Using NamedTemporaryFile is simpler (no subdirectory to manage) and gives us a .json suffix for free, which editors use for syntax highlighting.
A plain NamedTemporaryFile is sufficient here: we only need a single file, not a directory to hold it. Using NamedTemporaryFile is simpler (no subdirectory to manage) and gives us a .json suffix for free, which editors use for syntax highlighting.
filesystem: JsonEditor: offer interactive retry on error
When json.loads() fails (e.g. the user made a syntax mistake), prompt the user with "Re-open file for editing? [y]es/[n]o:" and loop back to the editor if they answer 'y' or 'yes'. If the user declines, return the original unmodified value so no write is attempted; the temp file is still cleaned up by __exit__() in that case.
When invoking `edit_binary_decoded` or `edit_record_decoded`, the temp file opened in the editor now contains the EF's encode/decode test vectors as //-comment lines below the JSON content, similar to how 'git commit' appends comments to the commit message template. The comment block is stripped before JSON parsing on save, so it has no effect on the written data.
The feature is implemented via a new module-level JsonEditor context manager class that encapsulates the full edit cycle:
* write JSON + examples to a TemporaryDirectory * invoke the editor * read back, strip //-comments, parse and return the result
pysim/pcsc: do not use getProtocol for protocol selection
The documentation of the getProtocol provided by pyscard says:
"Return bit mask for the protocol of connection, or None if no protocol set. The return value is a bit mask of CardConnection.T0_protocol, CardConnection.T1_protocol, CardConnection.RAW_protocol, CardConnection.T15_protocol"
This suggests that the purpose of getProtocol is not to determine which protocols are supported. Its purpose is to determine which protocol is currently selected (either through auto selection or through the explicit selection made by the API user). This means we are using getProtocol wrong.
So far this was no problem, since the auto-selected protocol should be a supported protocol anyway. However, the automatic protocol selection may not always return a correct result (see bug report from THD-siegfried [1]).
Let's not trust the automatic protocol selection. Instead let's parse the ATR and make the decision based on the TD1/TD2 bytes).
When invoking `edit_binary_decoded` or `edit_record_decoded`, the temp file opened in the editor now contains the EF's encode/decode test vectors as //-comment lines below the JSON content, similar to how 'git commit' appends comments to the commit message template. The comment block is stripped before JSON parsing on save, so it has no effect on the written data.
The feature is implemented via a new module-level JsonEditor context manager class that encapsulates the full edit cycle:
* write JSON + examples to a TemporaryDirectory * invoke the editor * read back, strip //-comments, parse and return the result
filesystem: JsonEditor: offer interactive retry on error
When json.loads() fails (e.g. the user made a syntax mistake), prompt the user with "Re-open file for editing? [y]es/[n]o:" and loop back to the editor if they answer 'y' or 'yes'. If the user declines, return the original unmodified value so no write is attempted; the temp file is still cleaned up by __exit__() in that case.
A plain NamedTemporaryFile is sufficient here: we only need a single file, not a directory to hold it. Using NamedTemporaryFile is simpler (no subdirectory to manage) and gives us a .json suffix for free, which editors use for syntax highlighting.
Add a Sphinx extension (docs/pysim_fs_sphinx.py) that hooks into the builder-inited event and generates docs/filesystem.rst before Sphinx reads any source files.
The generated page contains a hierarchical listing of all implemented EFs and DFs, organised by application/specification (UICC/TS 102 221, ADF.USIM/TS 31.102, ADF.ISIM/TS 31.103, SIM/TS 51.011). For each file, the class docstring and any _test_de_encode / _test_decode vectors are included as an encoding/decoding example table.
docs/filesystem.rst is fully generated at build time and is therefore added to .gitignore.
Add tests/unittests/test_fs_coverage.py that walks all pySim.* modules and verifies that every CardProfile, CardApplication, and standalone CardDF subclass with EF/DF children is either listed in the SECTIONS (and will appear in the docs) or explicitly EXCLUDED.
A plain NamedTemporaryFile is sufficient here: we only need a single file, not a directory to hold it. Using NamedTemporaryFile is simpler (no subdirectory to manage) and gives us a .json suffix for free, which editors use for syntax highlighting.
Add a Sphinx extension (docs/pysim_fs_sphinx.py) that hooks into the builder-inited event and generates docs/filesystem.rst before Sphinx reads any source files.
The generated page contains a hierarchical listing of all implemented EFs and DFs, organised by application/specification (UICC/TS 102 221, ADF.USIM/TS 31.102, ADF.ISIM/TS 31.103, SIM/TS 51.011). For each file, the class docstring and any _test_de_encode / _test_decode vectors are included as an encoding/decoding example table.
docs/filesystem.rst is fully generated at build time and is therefore added to .gitignore.
Add tests/unittests/test_fs_coverage.py that walks all pySim.* modules and verifies that every CardProfile, CardApplication, and standalone CardDF subclass with EF/DF children is either listed in the SECTIONS (and will appear in the docs) or explicitly EXCLUDED.
filesystem: JsonEditor: offer interactive retry on error
When json.loads() fails (e.g. the user made a syntax mistake), prompt the user with "Re-open file for editing? [y]es/[n]o:" and loop back to the editor if they answer 'y' or 'yes'. If the user declines, return the original unmodified value so no write is attempted; the temp file is still cleaned up by __exit__() in that case.
When invoking `edit_binary_decoded` or `edit_record_decoded`, the temp file opened in the editor now contains the EF's encode/decode test vectors as //-comment lines below the JSON content, similar to how 'git commit' appends comments to the commit message template. The comment block is stripped before JSON parsing on save, so it has no effect on the written data.
The feature is implemented via a new module-level JsonEditor context manager class that encapsulates the full edit cycle:
* write JSON + examples to a TemporaryDirectory * invoke the editor * read back, strip //-comments, parse and return the result
sphinxarg.ext generates generic sub-headings ("Named arguments", "Positional arguments", "Sub-commands", "General options", ...) for every argparse command and tool. These repeat across many files and trigger large numbers of autosectionlabel duplicate-label warnings.
Two-pronged fix:
* `autosectionlabel_maxdepth = 3` eliminates the depth-4+ warnings (sub-headings inside each individual command block). * `suppress_warnings` per file silences the residual depth-3 collisions ("serial reader", "decode_hex", "sub-commands", ...) that still appear across tool documentation files.
Cross-references into these generic argparse-generated sections are not a supported use-case, so suppressing the warnings is appropriate.
Add a Sphinx extension (docs/pysim_fs_sphinx.py) that hooks into the builder-inited event and generates docs/filesystem.rst before Sphinx reads any source files.
The generated page contains a hierarchical listing of all implemented EFs and DFs, organised by application/specification (UICC/TS 102 221, ADF.USIM/TS 31.102, ADF.ISIM/TS 31.103, SIM/TS 51.011). For each file, the class docstring and any _test_de_encode / _test_decode vectors are included as an encoding/decoding example table.
docs/filesystem.rst is fully generated at build time and is therefore added to .gitignore.
When invoking `edit_binary_decoded` or `edit_record_decoded`, the temp file opened in the editor now contains the EF's encode/decode test vectors as //-comment lines below the JSON content, similar to how 'git commit' appends comments to the commit message template. The comment block is stripped before JSON parsing on save, so it has no effect on the written data.
The feature is implemented via a new module-level JsonEditor context manager class that encapsulates the full edit cycle:
* write JSON + examples to a TemporaryDirectory * invoke the editor * read back, strip //-comments, parse and return the result
filesystem: JsonEditor: offer interactive retry on error
When json.loads() fails (e.g. the user made a syntax mistake), prompt the user with "Re-open file for editing? [y]es/[n]o:" and loop back to the editor if they answer 'y' or 'yes'. If the user declines, return the original unmodified value so no write is attempted; the temp file is still cleaned up by __exit__() in that case.
A plain NamedTemporaryFile is sufficient here: we only need a single file, not a directory to hold it. Using NamedTemporaryFile is simpler (no subdirectory to manage) and gives us a .json suffix for free, which editors use for syntax highlighting.
docs/conf.py: add autodoc_mock_imports for klein and twisted
The eSIM SM-DP+ server modules (`pySim.esim.es2p`, `pySim.esim.es9p`, `pySim.esim.http_json_api`) unconditionally import optional server-side dependencies at module level:
pySim.esim.es2p -- from klein import Klein pySim.esim.http_json_api -- from twisted.web.server import Request
Both imports fail during a docs build if the packages are absent or broken, causing three "autodoc: failed to import" warnings and three missing chapters in the generated manual.
Even when klein and twisted are installed, twisted 23.10.0 (the version pulled in transitively by smpp.twisted3's `Twisted~=23.10.0` constraint) is incompatible with Python 3.13+ because twisted.web.http unconditionally executes `import cgi`, a module that was removed from the standard library in Python 3.13.
Fix: add `autodoc_mock_imports = ['klein', 'twisted']` to conf.py. Sphinx inserts mock entries into sys.modules before each autodoc import attempt, so the modules can be imported and documented without requiring the real packages to be importable at build time.
pysim/pcsc: do not use getProtocol for protocol selection
The documentation of the getProtocol provided by pyscard says:
"Return bit mask for the protocol of connection, or None if no protocol set. The return value is a bit mask of CardConnection.T0_protocol, CardConnection.T1_protocol, CardConnection.RAW_protocol, CardConnection.T15_protocol"
This suggests that the purpose of getProtocol is not to determine which protocols are supported. Its purpose is to determine which protocol is currently selected (either through auto selection or through the explicit selection made by the API user). This means we are using getProtocol wrong.
So far this was no problem, since the auto-selected protocol should be a supported protocol anyway. However, the automatic protocol selection may not always return a correct result (see bug report from THD-siegfried [1]).
Let's not trust the automatic protocol selection. Instead let's parse the ATR and make the decision based on the TD1/TD2 bytes).
filesystem: JsonEditor: offer interactive retry on error
When json.loads() fails (e.g. the user made a syntax mistake), prompt the user with "Re-open file for editing? [y]es/[n]o:" and loop back to the editor if they answer 'y' or 'yes'. If the user declines, return the original unmodified value so no write is attempted; the temp file is still cleaned up by __exit__() in that case.
A plain NamedTemporaryFile is sufficient here: we only need a single file, not a directory to hold it. Using NamedTemporaryFile is simpler (no subdirectory to manage) and gives us a .json suffix for free, which editors use for syntax highlighting.
When invoking `edit_binary_decoded` or `edit_record_decoded`, the temp file opened in the editor now contains the EF's encode/decode test vectors as //-comment lines below the JSON content, similar to how 'git commit' appends comments to the commit message template. The comment block is stripped before JSON parsing on save, so it has no effect on the written data.
The feature is implemented via a new module-level JsonEditor context manager class that encapsulates the full edit cycle:
* write JSON + examples to a TemporaryDirectory * invoke the editor * read back, strip //-comments, parse and return the result
Add a Sphinx extension (docs/pysim_fs_sphinx.py) that hooks into the builder-inited event and generates docs/filesystem.rst before Sphinx reads any source files.
The generated page contains a hierarchical listing of all implemented EFs and DFs, organised by application/specification (UICC/TS 102 221, ADF.USIM/TS 31.102, ADF.ISIM/TS 31.103, SIM/TS 51.011). For each file, the class docstring and any _test_de_encode / _test_decode vectors are included as an encoding/decoding example table.
docs/filesystem.rst is fully generated at build time and is therefore added to .gitignore.
docs/conf.py: add autodoc_mock_imports for klein and twisted
The eSIM SM-DP+ server modules (`pySim.esim.es2p`, `pySim.esim.es9p`, `pySim.esim.http_json_api`) unconditionally import optional server-side dependencies at module level:
pySim.esim.es2p -- from klein import Klein pySim.esim.http_json_api -- from twisted.web.server import Request
Both imports fail during a docs build if the packages are absent or broken, causing three "autodoc: failed to import" warnings and three missing chapters in the generated manual.
Even when klein and twisted are installed, twisted 23.10.0 (the version pulled in transitively by smpp.twisted3's `Twisted~=23.10.0` constraint) is incompatible with Python 3.13+ because twisted.web.http unconditionally executes `import cgi`, a module that was removed from the standard library in Python 3.13.
Fix: add `autodoc_mock_imports = ['klein', 'twisted']` to conf.py. Sphinx inserts mock entries into sys.modules before each autodoc import attempt, so the modules can be imported and documented without requiring the real packages to be importable at build time.
sphinxarg.ext generates generic sub-headings ("Named arguments", "Positional arguments", "Sub-commands", "General options", ...) for every argparse command and tool. These repeat across many files and trigger large numbers of autosectionlabel duplicate-label warnings.
Two-pronged fix:
* `autosectionlabel_maxdepth = 3` eliminates the depth-4+ warnings (sub-headings inside each individual command block). * `suppress_warnings` per file silences the residual depth-3 collisions ("serial reader", "decode_hex", "sub-commands", ...) that still appear across tool documentation files.
Cross-references into these generic argparse-generated sections are not a supported use-case, so suppressing the warnings is appropriate.
sphinxarg.ext generates generic sub-headings ("Named arguments", "Positional arguments", "Sub-commands", "General options", ...) for every argparse command and tool. These repeat across many files and trigger large numbers of autosectionlabel duplicate-label warnings.
Two-pronged fix:
* `autosectionlabel_maxdepth = 3` eliminates the depth-4+ warnings (sub-headings inside each individual command block). * `suppress_warnings` per file silences the residual depth-3 collisions ("serial reader", "decode_hex", "sub-commands", ...) that still appear across tool documentation files.
Cross-references into these generic argparse-generated sections are not a supported use-case, so suppressing the warnings is appropriate.
docs/card-key-provider: fix heading levels and typo
The "ADM PIN" and "SCP02 / SCP03" sub-sections of "Field naming" used the '~' heading character, which Sphinx resolved to level 4 - skipping level 3 and throwing build ERRORs. As a result, both sub-sections had no heading at all. Change both to '^' (level 3) to match the other sub-sections in this file.
While at it, fix a typo: "consisting if" -> "consisting of".
pySim/EF.SMSP: fix encoding of TP-Destination Address
The TP-Destination Address in EF.SMSP uses the same encoding as the TS-Service Centre Address field. However, even though the encoding of both fields looks almost identical, it actually isn't.
The TS-Service Centre Address field encodes the length field as octets required for the call_number + one octet for ton_npi. (see also: 3GPP TS 24.011, section 8.2.5.2)
The TP-Destination Address uses the number of digits of the call_number directly in the length field. (see also: 3GPP TS 23.040, section 9.1.2.5)
pysim/pcsc: do not use getProtocol for protocol selection
The documentation of the getProtocol provided by pyscard says:
"Return bit mask for the protocol of connection, or None if no protocol set. The return value is a bit mask of CardConnection.T0_protocol, CardConnection.T1_protocol, CardConnection.RAW_protocol, CardConnection.T15_protocol"
This suggests that the purpose of getProtocol is not to determine which protocols are supported. Its purpose is to determine which protocol is currently selected (either through auto selection or through the explicit selection made by the API user). This means we are using getProtocol wrong.
So far this was no problem, since the auto-selected protocol should be a supported protocol anyway. However, the automatic protocol selection may not always return a correct result (see bug report from THD-siegfried [1]).
Let's not trust the automatic protocol selection. Instead let's parse the ATR and make the decision based on the TD1/TD2 bytes).
global_platform: install_cap_parser: argument groups cannot be nested
pySim-shell currently does not work on systems with Python 3.14+:
File ".../pysim/pySim/global_platform/__init__.py", line 868, in AddlShellCommands install_cap_parser_inst_prm_g_grp = install_cap_parser_inst_prm_g.add_argument_group() File "/usr/lib/python3.14/argparse.py", line 1794, in add_argument_group raise ValueError('argument groups cannot be nested') ValueError('argument groups cannot be nested')
The problem is that install_cap_parser creates a nested group inside of mutually exclusive group. argparse never supported group nesting properly, so it has been deprecated since Python 3.11, and eventually got removed in Python 3.14.
Remove group nesting, adjust the usage string, and implement the mutual exclusiveness enforcement manually in do_install_cap().
gen_install_parameters() had contradictory logic: the outer guard required all three arguments to be non-None/non-empty (making them mutually inclusive), while the inner checks then treated each one as optional.
Make each parameter independently optional (defaulting to None) and remove the all-or-nothing check. Simplify the function body to a straightforward single-pass construction of system_specific_params.
docs/put_key: add tutorial that explains how to manage global platform keys
With the increased interest in using GlobalPlatform features of UICC and eUICCs (OTA-SMS, applets, etc.), also comes an increased interest in how the related GlobalPlatform keys can be managed (key rotation, adding/removing keysets from/to a Security Domain).
Unfortunately, many aspects of this topic are not immediately obvious for the average user. Let's add a tutorial that contains some practical examples to shine some light on the topic.
docs/put_key: add tutorial that explains how to manage global platform keys
With the increased interest in using GlobalPlatform features of UICC and eUICCs (OTA-SMS, applets, etc.), also comes an increased interest in how the related GlobalPlatform keys can be managed (key rotation, adding/removing keysets from/to a Security Domain).
Unfortunately, many aspects of this topic are not immediately obvious for the average user. Let's add a tutorial that contains some practical examples to shine some light on the topic.
pysim/pcsc: do not use getProtocol for protocol selection
The documentation of the getProtocol provided by pyscard says:
"Return bit mask for the protocol of connection, or None if no protocol set. The return value is a bit mask of CardConnection.T0_protocol, CardConnection.T1_protocol, CardConnection.RAW_protocol, CardConnection.T15_protocol"
This suggests that the purpose of getProtocol is not to determine which protocols are supported. Its purpose is to determine which protocol is currently selected (either through auto selection or through the explicit selection made by the API user). This means we are using getProtocol wrong.
So far this was no problem, since the auto-selected protocol should be a supported protocol anyway. However, the automatic protocol selection may not always return a correct result (see bug report from THD-siegfried [1]).
Let's not trust the automatic protocol selection. Instead let's parse the ATR and make the decision based on the TD1/TD2 bytes).
pySim/EF.SMSP: fix encoding of TP-Destination Address
The TP-Destination Address in EF.SMSP uses the same encoding as the TS-Service Centre Address field. However, even though the encoding of both fields looks almost identical, it actually isn't.
The TS-Service Centre Address field encodes the length field as octets required for the call_number + one octet for ton_npi. (see also: 3GPP TS 24.011, section 8.2.5.2)
The TP-Destination Address uses the number of digits of the call_number directly in the length field. (see also: 3GPP TS 23.040, section 9.1.2.5)
Unfortunately we have mixed up the concept of TPDUs and APDUs in earlier versions of pySim-shell. This lead to problems with detecteding the APDU case properly (see also ISO/IEC 7816-3) and also prevented us from adding support for T=1.
This problem has been fixed long time ago and all APDUs sent from the pySim-shell code should be well formed and valid according to ISO/IEC 7816-3.
To ensure that we continue to format APDUs correctly as APDUs (and not TPDUs) we have added a mechanism to the LinkBase class that would either raise an exception or print a warning if someone mistakenly tries to send an APDU that is really a TPDU. Whether a warning is printed or an exception is raised is controlled via the apdu_strict member in the LinkBase class, which is false (print warning only) by default.
The reason why we have implemneted the mechanism this way was because we wanted to ensure that existing APDU scripts (pySim-shell apdu command) keep working, even though when those scripts uses APDUs which are formally invalid.
Sending a TPDU instead of an APDU via a T=0 link will still work in almost all cases. This is also the reason why this problem slipped through unnoticed for long time. However, there may still be subtile problems araising from this practice. The root of the problem is that it is impossible to distinguish between APDU case 3 and 4 when a TPDU instead of an APDU is sent. However in order to handle a case 4 APDU correctly we must be able to distinguish the APDU case correctly to handle the case correctly. ETSI TS 102 221, section 7.3.1.1.4, clause 4 is very clear about the fact that not (only) the status word (e.g. 61xx) but the APDU case is what matters.
To complete the logic in LinkBaseTpdu and to maintain compatibility (older APDU scripts), we must still be able to switch between the 'apdu_strict' mode and the non-strict mode. However, since pySim-shell, pySim-prog and pySim-read internally use proper APDUs, we may enable the 'apdu_strict' mode by default.
At the same time we will limit the effect of pySim-shell's apdu_strict setable to the apdu command only. By doing so, the bahviour of the apdu command is not altered. Users will still have to enable the 'strict' mode explicitly. At the same time all the internal functionality of pySim-shell will always use the 'strict' mode.
Main points/rationales of the refactoring, details below: 1) common validation implementation 2) offer classmethods
The new features are optional, and will be heavily used by batch personalization patches coming soon.
Implement Iccid and Imsi to use the new way, with a common abstract DecimalParam implementation.
So far leave the other parameter classes working as they always did, to follow suit in subsequent commits.
Details:
1) common validation implementation: There are very common validation steps in the various parameter implementations. It is more convenient and much more readable to implement those once and set simple validation parameters per subclass. So there now is a validate_val() classmethod, which subclasses can use as-is to apply the validation parameters -- or subclasses can override their cls.validate_val() for specialized validation. (Those subclasses that this patch doesn't touch still override the self.validate() instance method. Hence they still work as before this patch, but don't use the new common features yet.)
2) offer stateless classmethods: It is useful for... - batch processing of multiple profiles (in upcoming patches) and - user input validation to be able to have classmethods that do what self.validate() and self.apply() do, but do not modify any self.* members. So far the paradigm was to create a class instance to keep state about the value. This remains available, but in addition we make available the paradigm of a singleton that is stateless (the classmethods). Using self.validate() and self.apply() still work the same as before this patch, i.e. via self.input_value and self.value -- but in addition, there are now classmethods that don't touch self.* members.
