@digitalshieldfe/airgap-core

Shared UR encode/decode helpers, registry type constants, chain crypto utilities, and AirGapError (stable codes for host i18n).

UR types (URType)

| Constant | UR type string | |----------|----------------| | CryptoMultiAccounts | crypto-multi-accounts | | CryptoHDKey | crypto-hdkey | | CryptoPsbt | crypto-psbt | | EthSignRequest / EthSignature | eth-sign-request / eth-signature | | SolSignRequest / SolSignature | sol-sign-request / sol-signature | | TronSignRequest / TronSignature | tron-sign-request / tron-signature | | KeystoneSignRequest / KeystoneSignResult | keystone-sign-request / keystone-sign-result | | DeviceCall | digitalshield-app-call-device |

DeviceCall helpers

• buildDeviceCall / buildDeviceCallData / deviceCallToUr
• parseDeviceCall
• shortXfp — last 8 hex, aligned with DS getShortXfp

Payload CBOR is UTF-8 JSON (same as ds__release DigitalShieldRequestDeviceQR).

Shared crypto / encoding

Used by airgap-hot and airgap-cold (no duplicate implementations in those packages):

| Module | Exports (examples) | |--------|---------------------| | bytes.js | hexToBytes, bytesToHex, buffer helpers | | base58.js | Base58Check encode/decode | | rlp.js | RLP encode/decode for legacy ETH txs | | ethAddress.js | ETH address derivation / checksum | | tronAddress.js | TRON address helpers |

UR session

• decodeFrames / encodeAnimated / encodeSinglePart / urToJson
• Incomplete frame sets throw AirGapError with UR_DECODE_INCOMPLETE

AirGapError

All SDK packages throw AirGapError for user-facing failures:

import {
  AirGapError,
  AirGapErrorCode,
  isAirGapError,
  getAirGapErrorCode,
  airGapError,
} from "@digitalshieldfe/airgap-core";

| Field | Purpose | |-------|---------| | code | Stable string for i18n mapping (AirGapErrorCode.*) | | message | Default English description (fallback UI) | | params | Optional interpolation, e.g. { failedAttempts, maxAttempts } |

Full enum: src/errors.ts. PIN-specific subclasses live in @digitalshieldfe/airgap-keyring (PinLockedError, VaultWipedError).

See root README §12.