Scam Blocklist

Seashail can optionally fetch a signed scam-address blocklist and block writes to listed recipients/contracts.

This is designed to catch obvious mistakes (and known-bad destinations), not to make trading "safe" by itself.

Seashail does not ship a default blocklist. This feature is opt-in: you must configure a URL (and ideally pin the expected signing key) in config.toml.

Availability Model

The blocklist is a defense-in-depth filter, not a consensus rule.

If blocklist fetch/verification fails and no valid cache is available, Seashail continues without blocklist protection (fail-open).
Once a valid cache exists, Seashail will use it until it can refresh successfully.

What Gets Blocked

When enabled, Seashail will refuse to sign/broadcast writes where the recipient (and in some cases the relevant contract) is listed:

send_transaction: blocks sends to listed recipients
transfer_nft: blocks transfers to listed recipients (and blocks listed NFT contracts/mints)
buy_nft / sell_nft / bid_nft: blocks if the tx recipient/contract is listed

Config

In config.toml:

[http]
# Must be https:// (or http://localhost for local testing)
scam_blocklist_url = "https://example.com/seashail/scam-blocklist.json"

# Recommended: pin the expected Ed25519 verifying key (base64, 32 bytes).
# If omitted, Seashail will use the pubkey embedded in the fetched envelope.
scam_blocklist_pubkey_b64 = "..."

# How often to refresh the blocklist.
scam_blocklist_refresh_seconds = 21600

Signed Envelope Format

The fetched JSON must be an envelope:

version: currently 1
payload_b64: base64-encoded JSON payload bytes
signature_b64: base64 Ed25519 signature over the payload bytes
pubkey_b64: base64 Ed25519 verifying key (32 bytes)

The decoded payload JSON has:

evm: list of 0x-prefixed addresses
solana: list of base58 pubkeys

Operational Guidance

Prefer pinning scam_blocklist_pubkey_b64 so the trust anchor is in local config.
Host the envelope somewhere stable and cacheable.
Treat blocklisting as a defense-in-depth layer. Policy caps, allowlists, simulation, and confirmations still matter.