OTAMan — SIM OTA toolkit: PWA + local card server

OTAMan is an offline HTML/JS PWA for building APDU commands (SIM, USIM, GlobalPlatform RAM), assembling SCP80 secured packets per ETSI TS 102 225, and constructing Expanded Remote Application data format APDU per ETSI TS 102 226. A bundled pysim-otaman-server exposes a local HTTP API over pySim for live card operations: file manager, raw APDU, SIM Toolkit menu browsing, and OTA (SCP80) delivery.

Demo: otaman.atroshin.ru — the PWA alone, for experimenting. Install the server (below) for card-reader functions.

Quick start

PWA only (client-side tools): open frontend/index.html in any browser, or serve frontend/ with any static server. No Python required.

Full (PWA + card server):

git clone https://github.com/anttro/otaman.git
cd otaman
./setup.sh     # or setup.bat on Windows — creates .venv, installs pysim + server
./start.sh     # or start.bat — starts the server (it serves the PWA too)

Then open http://127.0.0.1:8080 — the UI and API share one origin, so no CORS or browser-permission setup is needed.

Build

Tailwind CSS is used for styling. After cloning, rebuild the CSS:

cd frontend
npm install
npm run build

Interface

Four top-level tabs: C-APDU, SCP80, Response parser, Card reader. The C-APDU and SCP80 tabs each have sub-tabs.

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C-APDU tab

Builds command APDUs (C-APDUs). Five sub-tabs cover different card generations and command sets.

SIM RFM

CLA = A0 (GSM 11.11 / ISO 7816-4).

Commands

Command	INS	Description
SELECT	A4	Select EF/DF by FID, path, dfname, or chain
UPDATE RECORD	DC	Update a record in a record-oriented EF
UPDATE BINARY	D6	Update binary content at an offset
READ RECORD	B2	Read a record
READ BINARY	B0	Read binary content
ERASE BINARY	0E	Erase binary at an offset
ACTIVATE FILE	44	Activate a file
DEACTIVATE FILE	04	Deactivate a file
VERIFY PIN	20	Verify PIN1 or PIN2
CHANGE PIN	24	Change PIN1 or PIN2

SELECT methods

Method	P1	P2	Input
By FID	00	00	2-byte FID (4 hex)
By full path from MF	08	00	Full path hex from MF
By DF name / AID	04	00	AID (application ID)
ADF RFM chain	00	00	Comma-separated FIDs, each selected in turn

Options

• Start with SELECT — checkbox to prepend a SELECT command before the operation. When unchecked, the operation is sent standalone with CLA.
• Selection mode (P2) — for record commands: Absolute (04), Next (06), Previous (02).
• Record size — pad/truncate data to the specified byte count.
• Allow P1/P2 editing — checkbox to enable manual override of P1/P2 bytes.

References

• ISO/IEC 7816-4: Organization, security and commands for interchange
• ETSI TS 102 226: Remote APDU structure for UICC based applications
• GSM 11.11: SIM-ME Interface

USIM RFM

CLA = 00 (ETSI TS 102 221). Same commands as SIM, but SELECT uses P1=09, P2=0C (by FID from current directory).

References

• ETSI TS 102 221: UICC-Terminal Interface; Physical and Logical Characteristics
• ETSI TS 102 226: Remote APDU structure for UICC based applications

Expanded Script

Builds Expanded Remote Application data format per ETSI TS 102 226 §5.2.1.

Format

Two encoding variants:

• Definite (AA): AA + length + Command TLVs
• Indefinite (AE): AE + 80 + Command TLVs + 00 00

Command TLVs

Type	Tag	Description
C-APDU	22	Raw APDU hex
Immediate Action	81	Proactive command or action indicator
Error Action	82	Proactive command on error
Script Chaining	83	Chaining data for multi-packet scripts

Immediate Action builder

When the type is set to Immediate Action, the tool provides a structured builder for:

• Action indicator: 81 (Proactive session indication) / 82 (Early response)
• Proactive command: REFRESH, DISPLAY TEXT, or PLAY TONE — with auto-generated COMPREHENSION-TLV data objects (command details, device identities, text string, tone, etc.)
• Custom hex: freeform input for manual TLV construction

Error Action supports the same builder (DISPLAY TEXT, PLAY TONE).

References

• ETSI TS 102 226 V13.0.0 §5.2.1: Expanded Remote Application data format
• ETSI TS 102 223: Card Application Toolkit (CAT) — proactive command structure
• ETSI TS 101 220: BER-TLV tag assignments

RAM/GP

CLA = 80 (GlobalPlatform Card Specification v2.3.1). Remote Application Management commands for card content management.

GP Commands Reference

Command	INS	P1	Description
INSTALL [for load]	E6	02	Register a load file for loading
INSTALL [for install]	E6	0C	Install an application or SD
INSTALL [for make selectable]	E6	10	Make an application selectable
INSTALL [for registry update]	E6	01	Update registry entries
INSTALL [for extradition]	E6	04	Extradition (move between SDs)
LOAD	E8	00	Load executable code blocks
DELETE	E4	00/80	Delete application or SD
GET STATUS	F2	80/40/20/10	Get card status
GET DATA	CA	tag	Read card data objects
STORE DATA	E2	00/40/80/C0	Store data (key, certificate, etc.)
SET STATUS	F0	80/40/60	Lifecycle state management
EXTERNAL AUTHENTICATE	82	00	SCP host authentication
INTERNAL AUTHENTICATE	88	00	Card challenge-response

INSTALL [for install] — Privilege Builder

Tag C7 in the INSTALL data field. Built from 3 privilege bytes (GP spec Tables 11-7, 11-8, 11-9):

Byte 1 (bits):

Bit	Privilege
b8	Security Domain
b7	DAP Verification
b6	Delegated Management
b5	Card Lock
b4	Card Terminate
b3	Card Reset
b2	CVM Management

Byte 2 (bits):

Bit	Privilege
b8	Trusted Path
b7	Authorized Management
b6	Token Verification
b5	Global Delete
b4	Global Lock
b3	Global Registry
b2	Final Application

Byte 3 (bits):

Bit	Privilege
b8	Receipt Generation

INSTALL [for install] — SIM/UICC Toolkit Parameters

Optional TLV objects appended to the INSTALL data field:

• Tag CA (SIM Toolkit): Priority, Timers, Text Length, Menu Entries, Menu Positions, Channels, MSL, TAR, Access Domain
• Tag 80 (UICC Toolkit, inside EA): Same fields minus Access Domain

MSL (Minimum Security Level) — SPI1 byte per TS 102 225:

Value	Meaning
00	No check
11	RC/CC/DS
12	RC/DS/CC
15	RC/DS/CC + MAC
16	RC/DS/CC + MAC + Cipher
19	RC/DS/CC + MAC + Cipher + DS

GET STATUS P1 values

Value	Meaning
80	Issuer Security Domain (ISD)
40	Applications and Supplementary Security Domains
20	Executable Load Files
10	ELF and their Executable Modules

GET STATUS P2 values

Value	Meaning
40	First/all occurrences, GP TLV format (default)
42	Next occurrence, GP TLV format
00	First/all, old format (deprecated)
02	Next, old format (deprecated)

GET DATA tag values

Tag	Data Object
42	Issuer Identification Number (IIN)
45	Card Image Number (CIN)
66	Card Data / SD Management Data
67	Card Capability Information
E0	Key Information Template
D3	Current Security Level
2F00	List of Applications (ISO 7816-4)
FF21	Extended Card Resources Info
5F50	SD Manager URL
C1	Sequence Counter (SCP02/03)
C2	Confirmation Counter
7F21	Certificate (SD public key)
5031	Certificate info (EF.OD)

DELETE P1 values

Value	Meaning
00	By AID
80	Delete associated objects

STORE DATA P1 values

Value	Meaning
00	Last block, no encryption
40	More blocks, no encryption
80	Last block, encrypted
C0	More blocks, encrypted

SET STATUS parameters

P1 (Status Type):

Value	Target
80	Issuer Security Domain
40	Application or Supplementary Security Domain
60	Security Domain and its associated Applications

P2 (State):

Value	Action
00	Unlock (return to previous state)
80	Lock (LOCKED state)

References

• GlobalPlatform Card Specification v2.3.1 (GPC_Spec_v2.3.1): Commands, Privileges, TLV structures
• ETSI TS 102 226 V13.0.0 §8.2.1.3.2: SIM/UICC Toolkit parameters, MSL, TAR, Access Domain

Conversion (SIM/USIM sidebars)

Value encoding conversions embedded in the SIM RFM and USIM RFM tabs.

IMSI → EF.IMSI

Per TS 31.102 §4.2.3. Encodes a 15-digit IMSI into the 9-byte EF.IMSI format:

• Byte 0: number of subsequent bytes (8)
• Odd/even indicator nibble in the last byte
• BCD digits, swapped nibble pairs per identity

Input: 15 decimal digits. Output: 18 hex characters.

MSISDN → BCD

Strips leading +, pads odd length with f, swaps nibble pairs.

ICCID → hex

Swaps nibble pairs of the ICCID string.

Provider Name → SPN

Per 3GPP TS 31.102 §4.2.5 (EF_SPN). Three encoding paths:

1. GSM 7-bit packed (all chars in GSM 7-bit default alphabet): prefix 01, DCS byte (spare bits), packed septets, 0xFF padding to 16 bytes.
2. UCS2 non-BMP (emoji / chars > U+FFFF): prefix 00, DCS 80, UTF-16BE, 0xFF padding to 16 bytes.
3. UCS2 BMP non-GSM7 (Cyrillic, etc.): prefix 00, DCS 81, base byte, per-char offsets, 0xFF padding to 16 bytes.

GSM 7-bit alphabet per 3GPP TS 23.038. Full extension table supported.

PLMN → EF_PLMNsel / PLMNwAcT

Per TS 31.102 §4.2.3. 3-byte BCD encoding for PLMN, plus optional 2-byte Access Technology selector.

Nibble swap

Swaps nibble pairs of an even-length hex string.

References

• 3GPP TS 31.102: Characteristics of the USIM Application
• 3GPP TS 23.038: Alphabets and language information
• ETSI TS 102 225: Secured packet structure for (U)SIM toolkit
• pySim: enc_imsi() implementation

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SCP80 tab

The SCP80 top-level tab groups SCP80-related views, switched by three pills: Secured Packet, Cards, and RAM. Assembles secured packets per ETSI TS 102 225.

Secured Packet

Builds SCP80 secured packets per ETSI TS 102 225.

Packet structure

Field	Size	Description
CPI	1	Command Packet Identifier (02)
CPL	1	Command Packet Length
CHI	1	Command Header Identifier (01)
CHL	1	Command Header Length
SPI	2	Security Parameter Indicator
KIc	1	Key Identifier for ciphering
KID	1	Key Identifier for MAC
TAR	3	Toolkit Application Reference
CNTR	5	Replay counter
PCNTR	1	Padding counter
RC/CC/DS	8	Cryptographic Checksum / MAC
Secured Data	variable	Padded APDU (encrypted if required)

SPI1 (Security Level)

SPI1 bit layout (TS 102 225 §5.1.1): b8–b6 padding, b5–b4 counter, b3 ciphering, b2–b1 RC/CC/DS.

Value	Security	Ciphering	Counter (b5 b4)
00	None	No	00 none
01	RC	No	00 none
02	CC/MAC	No	00 none
06	CC/MAC	Yes	00 none
0A	CC/MAC	No	01 available
0E	CC/MAC	Yes	01 available
12	CC/MAC	No	10 higher
16	CC/MAC	Yes	10 higher
1A	CC/MAC	No	11 +1
1E	CC/MAC	Yes	11 +1

AES requires b5 b4 = 10 (higher) or 11 (+1) per TS 102 225 §5.1.2 and §5.1.3.1. The 3DES values 00/01/02/06 (no counter) remain valid for 3DES only.

SPI2 (PoR settings)

Value	Mode	Security	Cipher
00	No PoR	—	No
01	PoR required	None	No
05	PoR required	RC	No
09	PoR required	CC	No
0D	PoR required	DS	No
11	PoR required	None	Yes
02	PoR on error	None	No
06	PoR on error	RC	No

Crypto

• 3DES-CBC encryption (zero ICV), supporting 8, 16, and 24 byte keys — deprecated since Rel-18, still supported for backwards compatibility
• AES-CBC encryption (zero ICV, zero-padded to 16), supporting 16, 24, and 32 byte keys (TS 102 225 §5.1.2, KIc x2)
• Retail MAC (ISO 9797-1 MAC algorithm 3) for the DES/3DES cryptographic checksum
• AES-CMAC (NIST SP 800-38B, truncated to 8 octets) for the AES cryptographic checksum (TS 102 225 §5.1.3.1, KID x2)
• Padding byte configurable (00 per TS 102 225 default, or FF)

PoR (Proof of Reception)

PoR confirms the card received and executed the secured packet. Two modes:

SPI2 (bit 5)	Mode	Description
0x00	Delivery PoR	PoR is returned in the ENVELOPE response SW+data
0x20	Submit PoR	PoR is sent back as an SMS-SUBMIT via a proactive FETCH command

Delivery PoR (SPI2 01) is simpler — the card returns the PoR directly in the ENVELOPE response. Submit PoR (SPI2 21) is used when the card cannot respond inline (e.g. during ELF operations where the ENVELOPE response space is limited).

References

• ETSI TS 102 225 V18.1.0: Secured packet structure for UICC based applications
• ETSI TS 102 226: Remote APDU structure for UICC based applications
• ISO 9797-1: MAC algorithms
• NIST SP 800-38B: CMAC

Cards

Stores saved card configurations (presets). Each preset stores the cryptographic keys, SPI settings, TAR, and replay counter needed for SCP80 operations.

Field	Description
SPI1 / SPI2	Security level and PoR settings
KIc / KID key	Encryption and MAC key hex
KIc / KID index	Key version number
TAR	Toolkit Application Reference (3 bytes)
Counter (CNTR)	10-digit hex replay counter, auto-incremented after each successful SCP80 send

Add a card: fill in the name, SPI1/SPI2, KIc/KID keys and indices, TAR, and click Add. The card appears in the list and becomes available in the RAM tab's Card preset dropdown.

Edit a card: click a card in the list, modify fields, click Save.

Delete a card: select a card, click Delete. Removes the preset from localStorage.

Counter: the 10-digit hex counter (CNTR) is auto-incremented after each successful SCP80 send (both manual Secured Packet sends and RAM operations). The updated counter is saved back to the preset automatically.

RAM

All RAM operations are delivered as SCP80 secured packets (ETSI TS 102 225) via SMS-PP-DOWNLOAD ENVELOPE. The card must support SCP03 (AES or 3DES) for secure transport.

Select a saved card configuration from the Card preset dropdown. If no preset is selected, the RAM tab warns and refuses to execute.

The RAM subtab offers two operations selected from the Operation dropdown:

Operation	Description
Explore Card (all GP data)	Queries GET STATUS for ISD, Applications, ELFs, and ELF Modules, plus GET DATA FF21 for memory info. Results appear in an explorer view with per-item Delete buttons.
Install Package (.cap file)	Sends a .cap file to the card via the server: INSTALL[for load] → LOAD ×N → INSTALL[for install (+make selectable)].

Explorer View

After "Explore Card" runs, the explorer view displays:

• ISD — AID, lifecycle, privileges (no delete; the ISD cannot be removed)
• Applications — AID, lifecycle, privileges, associated ELF/SD. Each has a Delete button (GP DELETE by AID).
• Executable Load Files — AID, lifecycle, version, module AIDs. Each has Delete (ELF only) and Delete All (cascade: ELF + modules + installed Applications, P2=0x80) buttons.

Delete confirms via a browser prompt before sending the GP DELETE command via SCP80. The explorer auto-refreshes after a successful deletion.

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Response parser tab

Decodes a raw command response: pick the command that was sent, enter the SW (e.g. 9000) and the response data hex, then press Decode.

• Command — SIM/USIM group (SELECT, STATUS, READ/UPDATE, PIN ops, CAT commands like TERMINAL PROFILE/ENVELOPE/FETCH/TERMINAL RESPONSE, MANAGE CHANNEL, ...) or RAM/GP group (INSTALL, LOAD, DELETE, GET/STORE DATA, auth, SCP commands).
• SW decode — status words resolved against generic, UICC (TS 102 221), and GlobalPlatform maps, with context auto-detected.
• Privilege decode — GET DATA / INSTALL response payloads decode the privilege bytes into human-readable flags.
• Response data — raw hex rendered and interpreted per command (e.g. SELECT FCP templates).

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Card Reader (pySim integration)

Connects to the bundled pysim-otaman-server for live card operations.

Browser restriction: when the PWA is served from a public HTTPS host, reaching the local server (http://127.0.0.1:8080) requires two things: the server must send Access-Control-Allow-Private-Network: true (pysim-otaman-server ≥ 1.6.1 does this automatically), and the browser must be allowed to access the local network — in Chrome/Edge/Vivaldi: Site settings → Local network access → allow the site (or accept the permission prompt). Without the browser permission, the request to 127.0.0.1 is blocked before any preflight is sent.

File Browser

Browse the UICC filesystem in a tree view. Files are shown with names, FIDs, and AIDs (for ADFs). Click to read contents.

• Read — reads the selected file (auto-detects transparent vs record files)
• Edit — switch to edit mode, modify hex data, click Save to write back
• Raw / Decoded — toggle between hex dump and pysim-decoded JSON view

Custom Files

Files not in pysim's model can be added manually:

1. Switch to the Custom files sub-tab
2. Enter the file path (e.g., 3F00/6F46) and an alias (e.g., EF.SPN)
3. Click Add — the file appears in the tree in italics (unverified)
4. Click the file to verify existence — on success, it behaves like a model file

Custom files persist in localStorage across sessions. Export/import as JSON for sharing.

Proactive UICC Pill

The Proactive UICC sub-tab in the Card Reader provides real-time CAT session interaction:

Subscribed Events — the card's SET UP EVENT LIST is displayed with per-event Send buttons. Clicking opens a form specific to the event type:

• No-data events (User Activity, Idle Screen, etc.) — single-click confirmation
• Location Status — dropdown for Normal / Limited / No service
• Access Technology Change — dropdown for all 13 RAT types
• Card Reader Status, Language, UICC Access — appropriate inputs
• Network Rejection — full adaptive form with registration type dropdown (LU / GPRS / EPS / 5GS), location fields (MCC, MNC, LAC, RAC, TAC), access technology selection, and 53-cause unified rejection cause code dropdown covering EMM, GMM, 5GMM, and LU causes

Proactive Command Log — chronological list of proactive commands encountered (seconds elapsed, type code, name, byte count). Covers SET UP MENU, SET UP EVENT LIST, POLL INTERVAL, DISPLAY TEXT, SELECT ITEM, and PROVIDE LOCAL INFORMATION.

PLI Data Dictionary — editable per-qualifier hex values for all 22 PROVIDE LOCAL INFORMATION qualifiers (TS 102 223 + TS 131 111). 10 qualifiers have inline decode/encode forms (toggle):

Code	Decoded fields
00	MCC, MNC, LAC/TAC
01	IMEI (15 digits)
03	Date, Time, TZ offset
04	Language (2-char code)
05	ME Status, Timing Advance
06	Access Technology (dropdown)
08	IMEISV (16 digits)
09	Search Mode (Auto/Manual)
0A	Battery charge (%)
0E	Multiple Access Technologies (comma-list)

Values persist on the server until restart. Apply → hex updates; Save → POSTs to server. The server will use these values to populate TERMINAL RESPONSE data for future PLI proactive commands.

Command Hints

Type a command name in the pySim command line input. Usage hints appear as a tooltip after 300ms. Command autocomplete suggestions appear above the input.

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PWA

OTAMan is a Progressive Web App and can be installed for offline use. Use the INSTALL PWA button in the header, or use the browser's install prompt.

• Service worker pre-caches all assets on first visit
• App icons at 192×192 and 512×512

Server (pysim-otaman-server)

The bundled Python server wraps pySim and serves both the OTAMan PWA (from frontend/) and a JSON API under /api/*.

Prerequisites

• Python 3.8+ with pip, and Git
• Smart card reader (PC/SC or serial/FTDI) — PC/SC is preferable (pcsc-lite + ccid on Linux)
• Windows — use Python 3.10–3.13 (3.13 recommended): pyscard ships precompiled wheels for these versions. On 3.9 / 3.14 it builds from source (needs MSVC C++ Build Tools). The SMPP bridge (smpp.twisted3) is intentionally skipped on Windows.

Scripts

Script	What it does
setup.sh / setup.bat	Creates .venv/, installs pysim and the server. Run once after cloning.
start.sh / start.bat	Starts the server from the venv (serves the PWA + API on :8080).

start.sh auto-detects the reader (PC/SC if pcscd is running, else /dev/ttyUSB0); start.bat always uses -p 0 (PC/SC is built into Windows). If no reader is found the server still starts ("Reader: none") — initialize the card later via the Equip button.

Manual installation

python3 -m venv .venv
source .venv/bin/activate          # Linux/macOS   (Windows: .venv\Scripts\activate)
pip install git+https://github.com/osmocom/pysim.git
pip install -e .                   # editable — serves frontend/ from the source tree
pysim-otaman-server --http-port 8080

CLI options

Option	Description
--http-host	Bind address (default: 127.0.0.1)
--http-port	TCP port (default: 8080)
--web-dir	Directory with PWA static files (default: <repo>/frontend)
-p / --pcsc-device	PC/SC reader slot number
-d / --device	Serial device path
--no-card-init	Skip card init to preserve the CAT session (no file manager)
--apdu-trace	Log APDU-level traces to stderr
--log-requests	Log request/response payloads to stderr
--sms-oa / --sms-sm-sc	SMS-DELIVER originating address / SM-SC for PoR-in-submit
--terminal-profile	TERMINAL PROFILE payload hex (default 10-byte GSM profile)
--poll-interval	Idle interval before automatic STATUS polling (default 30s)

Troubleshooting

• "Failed to establish context: Access denied" — pcscd isn't running or the user lacks permission: sudo systemctl enable --now pcscd && sudo usermod -a -G pcscd $USER.
• "device file /dev/ttyUSB0 does not exist" — no serial reader; connect a USB reader or pass -d explicitly. The server still starts without a reader.

API reference

See docs/api.md for the full endpoint reference.

Theme

Dark theme is supported. The app follows the OS preference on first visit, and a manual toggle button (🌙/☀️) at the top-right corner persists the choice in localStorage.

Localisation

The UI is in English with Russian language support. Language is detected from the browser's navigator.language preference. A manual toggle button (EN/RU) in the header persists the choice in localStorage.

Version compatibility

PWA (OTAMan)	Server	Status
1.x.x	1.x.x	✅ Compatible
1.x.x	0.x.x	❌ Outdated — update server
1.x.x	2.x.x+	⚠️ Server newer — update PWA

The PWA checks the server version on connect via GET /api/version and warns if versions are incompatible.