Ledger Proofs

Introduction

The FinP2P network enables secure, decentralized financial transactions across disparate ledgers. Central to this is the
Execution Plan (EP), a mechanism for orchestrating multi-step operations. This document details additional capabilities
in the EP trust model for allowing ledger adapters to provide proofs of execution of EP instructions.

Ledger Operation Proofs

Ledger operations produce a Receipt, which serves as a guarantee from the underlying platform of a transaction that
occurred in its ledger. This receipt is provided by an adapter to the router to record transactions, either as part of
the EP instruction completion proposal phase or individually to record transactions that were triggered externally to
FinP2P and affect the investors' accounts.

To further enhance this guarantee, an additional proof can be attached to the Receipt. By supplying the proof as part of
the Receipt, the organization adds another layer of trust and a guarantee that a transaction was recorded in the ledger.
This can increase the trust of other parties that may not have direct access to the ledger.

Organizations can provide segregated private keys for ledger proofs. The information about the key used for verification
is provided by the FinP2P asset policy, which provides general information about the tokenization platform capabilities
and is published as metadata on specific asset profiles. These keys can be further pinned by other parties to reduce the
need to trust external configuration dependencies.

Overview of Proof Types

  • Receipt Signature Based:
    • Ledgers may apply a digital signing algorithm encoding the Receipt transaction information into a digest, which
      will be signed by a private key owned exclusively by the organization controlling the ledger or tokenization
      platform. The additional signature-based proof adds another layer of reliability for the guarantee provided by the
      organization that the Receipt transaction was indeed recorded in its ledger, and the data was not tampered with.
    • The proof is a digital signature applied to the Receipt data and signed by a private key owned by the controlling
      organization of the tokenization platform, the structure of the message to be signed can follow the below EIP712
      structure of Hashlist structure.
    • The key may differ from the Organization's Router private key, which is associated with the public key identity of
      the organization in the FinP2P network (AKA FinID).

Other proof types to be added soon:

  • Zero Knowledge:
    • For ledgers and tokenization platforms that support Zero Knowledge Proofs (ZKP), the ledger may provide a ZKP for
      the existence of the transaction within a blockchain block and that the network has reached consensus about the
      block.
  • Ledger Specific Proofs:
    • Ledgers may supply proof of a transaction being recorded on a ledger by providing ledger-specific cryptographic
      proofs of this action. This may require additional key pre-setup to ensure other parties can validate the proof.

Receipt Signature Based proof

EIP712 Proof Structure

Type Definitions

The following table describes the EIP-712 type definitions:

OrderType NameField NameField TypeDescription
1EIP712DomainnamestringName of the signing domain
2versionstringVersion of the signing domain
3chainIduint256Chain ID where the contract is deployed
4verifyingContractstringAddress of the verifying contract
5SourceaccountTypestringType of the account
6SourcefinIdstringFinID of the account
7DestinationaccountTypestringType of the account
8DestinationfinIdstringFinID of the account
9TradeDetailsexecutionContextExecutionContextExecution plan context
10ExecutionContextexecutionPlanIdstringExecution plan ID
11ExecutionContextinstructionSequenceNumberstringInstruction sequence number
12TransactionDetailsoperationIdstringOperation ID of the transaction
13TransactionDetailstransactionIdstringTransaction ID on the ledger
14AssetassetIdstringID of the asset
15AssetassetTypestringType of the asset
16ReceiptidstringID of the receipt
17ReceiptoperationTypestringThe operation type (e.g., hold, release)
18ReceiptsourceSourcethe source account
19ReceiptdestinationDestinationthe destination account
20ReceiptassetAssetthe asset
21ReceipttradeDetailsTradeDetailsthe trade details relating to the EP
22ReceipttransactionDetailsTransactionDetailsthe transaction details

Message Fields

The following table describes the fields included in the EIP-712 message:

Field NameField TypeDescription
idstringID of the receipt
operationTypestringThe operation type (e.g., hold, release)
sourceAccountTypestringType of the source account
sourceFinIdstringFinancial ID of the source account
destinationAccountTypestringType of the destination account
destinationFinIdstringFinancial ID of the destination account
assetIdstringID of the asset
assetTypestringType of the asset
executionPlanIdstringExecution plan ID
instructionSequenceNumberstringInstruction sequence number
operationIdstringOperation ID of the transaction
transactionIdstringTransaction ID

JSON Samples:

EIP712 Template
{
  "domain": {
    "chainId": 1,
    "name": "FinP2P",
    "verifyingContract": "0xCcCCccccCCCCcCCCCCCcCcCccCcCCCcCcccccccC",
    "version": "1"
  },
  "message": {
    "id": "receipt123456",
    "operationType": "hold",
    "source": {
      "accountType": "sourceAccountType",
      "finId": "sourceFinId"
    },
    "destination": {
      "accountType": "destinationAccountType",
      "finId": "destinationFinId"
    },
    "asset": {
      "assetId": "asset123",
      "assetType": "finp2p"
    },
    "tradeDetails": {
      "executionContext": {
        "executionPlanId": "ep123",
        "instructionSequenceNumber": "1"
      }
    },
    "transactionDetails": {
      "operationId": "op123",
      "transactionId": "tx123"
    }
  },
  "primaryType": "Receipt",
  "types": {
    "EIP712Domain": [
      {
        "name": "name",
        "type": "string"
      },
      {
        "name": "version",
        "type": "string"
      },
      {
        "name": "chainId",
        "type": "uint256"
      },
      {
        "name": "verifyingContract",
        "type": "address"
      }
    ],
    "Source": [
      {
        "name": "accountType",
        "type": "string"
      },
      {
        "name": "finId",
        "type": "string"
      }
    ],
    "Destination": [
      {
        "name": "accountType",
        "type": "string"
      },
      {
        "name": "finId",
        "type": "string"
      }
    ],
    "TransactionDetails": [
      {
        "name": "operationId",
        "type": "string"
      },
      {
        "name": "transactionId",
        "type": "string"
      }
    ],
    "Asset": [
      {
        "name": "assetId",
        "type": "string"
      },
      {
        "name": "assetType",
        "type": "string"
      }
    ],
    "ExecutionContext": [
      {
        "name": "executionPlanId",
        "type": "string"
      },
      {
        "name": "instructionSequenceNumber",
        "type": "string"
      }
    ],
    "TradeDetails": [
      {
        "name": "executionContext",
        "type": "ExecutionContext"
      }
    ],
    "Receipt": [
      {
        "name": "id",
        "type": "string"
      },
      {
        "name": "operationType",
        "type": "string"
      },
      {
        "name": "source",
        "type": "Source"
      },
      {
        "name": "destination",
        "type": "Destination"
      },
      {
        "name": "asset",
        "type": "Asset"
      },
      {
        "name": "tradeDetails",
        "type": "TradeDetails"
      },
      {
        "name": "transactionDetails",
        "type": "TransactionDetails"
      }
    ]
  }
}

Ledger adapter API template type
{
  "signature": {
    "hashFunc": "keccak_256",
    "signature": "56f471d1010b3cad0e1461886c2bb9c85bdb0bcc288f857bf8e877f147a3a2e97d21053fcaff61593df9cac2701c889e0e43e7872d38d8696739e3fbf6479eb2",
    "template": {
      "domain": {
        "chainId": 1,
        "name": "FinP2P",
        "verifyingContract": "0xCcCCccccCCCCcCCCCCCcCcCccCcCCCcCcccccccC",
        "version": "1"
      },
      "hash": "b55a46f6fa8188ab834de7bd4c9105b5ede3c7accc9eb320c423fce8e2d7e255",
      "message": {
        "id": "receipt123456",
        "operationType": "hold",
        "source": {
          "accountType": "sourceAccountType",
          "finId": "sourceFinId"
        },
        "destination": {
          "accountType": "destinationAccountType",
          "finId": "destinationFinId"
        },
        "asset": {
          "assetId": "asset123",
          "assetType": "finp2p"
        },
        "tradeDetails": {
          "executionContext": {
            "executionPlanId": "ep123",
            "instructionSequenceNumber": "1"
          }
        },
        "transactionDetails": {
          "operationId": "op123",
          "transactionId": "tx123"
        }
      },
      "primaryType": "Receipt",
      "type": "EIP712",
      "types": {
        "definitions": [
          {
            "fields": [
              {
                "name": "name",
                "type": "string"
              },
              {
                "name": "version",
                "type": "string"
              },
              {
                "name": "chainId",
                "type": "uint256"
              },
              {
                "name": "verifyingContract",
                "type": "address"
              }
            ],
            "name": "EIP712Domain"
          },
          {
            "fields": [
              {
                "name": "accountType",
                "type": "string"
              },
              {
                "name": "finId",
                "type": "string"
              }
            ],
            "name": "Source"
          },
          {
            "fields": [
              {
                "name": "accountType",
                "type": "string"
              },
              {
                "name": "finId",
                "type": "string"
              }
            ],
            "name": "Destination"
          },
          {
            "fields": [
              {
                "name": "operationId",
                "type": "string"
              },
              {
                "name": "transactionId",
                "type": "string"
              }
            ],
            "name": "TransactionDetails"
          },
          {
            "fields": [
              {
                "name": "assetId",
                "type": "string"
              },
              {
                "name": "assetType",
                "type": "string"
              }
            ],
            "name": "Asset"
          },
          {
            "fields": [
              {
                "name": "executionPlanId",
                "type": "string"
              },
              {
                "name": "instructionSequenceNumber",
                "type": "string"
              }
            ],
            "name": "ExecutionContext"
          },
          {
            "fields": [
              {
                "name": "executionContext",
                "type": "ExecutionContext"
              }
            ],
            "name": "TradeDetails"
          },
          {
            "fields": [
              {
                "name": "id",
                "type": "string"
              },
              {
                "name": "operationType",
                "type": "string"
              },
              {
                "name": "source",
                "type": "Source"
              },
              {
                "name": "destination",
                "type": "Destination"
              },
              {
                "name": "asset",
                "type": "Asset"
              },
              {
                "name": "tradeDetails",
                "type": "TradeDetails"
              },
              {
                "name": "transactionDetails",
                "type": "TransactionDetails"
              }
            ],
            "name": "Receipt"
          }
        ]
      }
    }
  },
  "type": "signatureProofPolicy"
}

Hashlist Proof Structure

The signature template for the Receipt proof in Hashlist format, The Hashlist signature format involves creating an
array of hashes, where each hash represents a group of values.

The list of fields as defined in Message Fields is hashed in order to create a Hash Group (HG). The
HG is then hashed to create a Hashlist. The Hashlist is then signed by the sender's private key.

HG = hash('SHA3-256', [fields by order]);
hashList = hash('SHA3-256', [HG]);
Signature = sign(sender private secp256k1 key, hashList)