The client-side pre-check rejected legitimate keys before the daemon ever
saw them, surfacing "Unrecognized key format" / a cryptic daemon "Invalid"
error. Two concrete defects plus the brittle heuristic behind them:
- Viewing keys: isViewingKey looked for Zcash's "zxview" extended-FVK
prefix, but DragonX's z_exportviewingkey emits a Sapling *incoming*
viewing key (HRP "zivks"), which z_importviewingkey is the only form the
daemon decodes. Every real DragonX viewing key was refused. (F1)
- Uncompressed transparent WIF: the length+first-char heuristic accepted
{5,K,L,U} only, but a version-188 uncompressed key starts with '7'. (F2)
Replace the heuristic with structural validation using the existing
checksum validators (F3): add util::decodeBase58Check (checksum-stripped
payload) and util::bech32Hrp (HRP of a valid Bech32 string). Transparent
keys are now accepted by decoding Base58Check and checking the payload is a
33/34-byte secret key with a DragonX SECRET_KEY version byte (188 main/
regtest, 128 testnet) — covering compressed and uncompressed, rejecting
addresses/typos by real checksum. Viewing keys are matched by the real
incoming-VK HRPs (zivks / zivktestsapling / zivkregtestsapling).
The Sweep gate and the dialog's live type indicator run off the same
predicates, so they are fixed too (F4). Messaging now names the likely
cause and appends a wrong-coin/network hint to the daemon's raw "Invalid"
error (F5).
Adds testPrivateKeyImportRecognition plus decodeBase58Check/bech32Hrp
coverage; suite green (1/1).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>