stellar-sdk/com.soneso.stellar.sdk.smartaccount.core/ExternalSigner

ExternalSigner

data class ExternalSigner(val verifierAddress: String, val keyData: ByteArray) : SmartAccountSigner

An external signer using a verifier contract for custom signature validation.

External signers delegate signature verification to a Soroban contract. The verifier contract receives the public key data and signature, and returns whether the signature is valid. This enables support for non-native signature schemes like WebAuthn (secp256r1) and Ed25519.

The verifier contract address must be a C-address, and the key data contains the public key bytes plus any additional authentication data (like WebAuthn credential IDs).

Example:

// WebAuthn signer
val webAuthnSigner = ExternalSigner.webAuthn(
    verifierAddress = "CBCD1234...",
    publicKey = secp256r1PublicKey,
    credentialId = webAuthnCredentialId
)

// Ed25519 signer
val ed25519Signer = ExternalSigner.ed25519(
    verifierAddress = "CDEF5678...",
    publicKey = ed25519PublicKey
)