Convert your confidential MPT balance back to a public balance. This debits the confidential spending balance and credits the public balance with the plaintext amount. For the issuer's second account, this returns confidential supply to the issuer account reserve.
Note
Only the spending balance can be converted back. Amounts in the inbox must first be merged into the spending balance using the ConfidentialMPTMergeInbox transaction.
Requires the ConfidentialTransfer amendment. Loading...
{
"TransactionType": "ConfidentialMPTConvertBack",
"Account": "rEw98xHU9KvZwKUZpXF9pWAum98dzbMb5N",
"MPTokenIssuanceID": "003CE562586390F0CB47C7EB3A42740AEFDC9A1E0B5CA1AC",
"MPTAmount": "3000",
"HolderEncryptedAmount": "03838E58829AFA0778AAF1C3A4452F26ACB7090D71856D99A744BA5E2F184379890333409E592066D1B869876B1C551664CA588DAB3F73598A481E1DC507D7F80E59",
"IssuerEncryptedAmount": "03838E58829AFA0778AAF1C3A4452F26ACB7090D71856D99A744BA5E2F1843798903762CDD3C8261D9362DE29B7BFB1399A7BB85607C42513D45110234012E074CFD",
"BlindingFactor": "6FE59620FCA03CE87F921AE5885DA2ECC570AEA139F10733ACA4C865847EAF3C",
"ZKProof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
"BalanceCommitment": "021AE9AACEA7CD9F58F735A6DBD671BF7824EF1E7A99731EBDE88502638F9D737F",
"Fee": "10",
"Sequence": 3990889
}In addition to the common fields, ConfidentialMPTConvertBack transactions use the following fields:
| Field | JSON Type | Internal Type | Required? | Description |
|---|---|---|---|---|
AuditorEncryptedAmount | String | Blob | No | A 66-byte Ciphertext for the auditor. Required if AuditorEncryptionKey is present on the issuance. |
BalanceCommitment | String | Blob | Yes | A 33-byte cryptographic commitment to the user's confidential spending balance. |
BlindingFactor | String | UInt256 | Yes | The 32-byte scalar value used to encrypt the amount. Used by validators to verify the ciphertexts match the plaintext MPTAmount. |
HolderEncryptedAmount | String | Blob | Yes | A 66-byte Ciphertext to be subtracted from the holder's ConfidentialBalanceSpending. |
IssuerEncryptedAmount | String | Blob | Yes | A 66-byte Ciphertext to be subtracted from the issuer's mirror balance. |
MPTAmount | String | UInt64 | Yes | The plaintext amount to credit to the public balance. |
MPTokenIssuanceID | String | UInt192 | Yes | The unique identifier for the MPT issuance. |
ZKProof | String | Blob | Yes | An 816-byte proof bundle containing a compact ConvertBack sigma proof and a single Bulletproof range proof. See Proof Structure for details. |
The ZKProof field contains an 816-byte bundle made up of two parts:
A compact ConvertBack sigma proof (128 bytes) that verifies the holder owns the spending balance and that the
BalanceCommitmentis correctly derived from it.A single Bulletproof range proof (688 bytes) that verifies that the remaining balance after withdrawal is non-negative.
Besides errors that can occur for all transactions, ConfidentialMPTConvertBack transactions can result in the following transaction result codes:
| Error Code | Description |
|---|---|
tecBAD_PROOF | The Zero-Knowledge Proof verification failed. Common causes include: - The BlindingFactor fails to verify the integrity of the ciphertexts.- The provided ZKProof fails the compact sigma or range proof check.- The account's confidential spending balance is less than the requested MPTAmount, so the range proof of the remaining balance fails. |
tecINSUFFICIENT_FUNDS | The issuance's ConfidentialOutstandingAmount is less than the requested MPTAmount. |
tecLOCKED | The MPT is locked for the account, or the issuance is globally locked. |
tecNO_AUTH | The issuance requires authorization and the account's MPToken is not authorized. |
tecNO_PERMISSION | The transaction lacks the required permissions. Common causes include: - The issuance does not have the Can Hold Confidential Balance flag enabled. - The account's MPToken is missing the ConfidentialBalanceSpending or HolderEncryptionKey field.- The issuance has AuditorEncryptionKey set but the transaction omits AuditorEncryptedAmount (or the reverse). |
tecOBJECT_NOT_FOUND | The MPTokenIssuance or the account's MPToken does not exist. |
temBAD_AMOUNT | The MPTAmount is zero or exceeds the maximum allowable MPT amount. |
temBAD_CIPHERTEXT | One or more encrypted amount fields (HolderEncryptedAmount, IssuerEncryptedAmount, or AuditorEncryptedAmount) has an incorrect length or represents an invalid elliptic curve point. |
temDISABLED | The ConfidentialTransfer amendment is not enabled. |
temMALFORMED | The transaction is malformed. Common causes include: - The Account is the issuer of the MPTokenIssuanceID.- BalanceCommitment is not a valid 33-byte compressed elliptic curve point.- The ZKProof length is not 816 bytes. |