CSC Ledger Accounts

An "Account" in the CSC Ledger represents a holder of CSC and a sender of transactions. The core elements of an account are:

  • An identifying address, such as cDarPNJEpCnpBZSfmcquydockkePkjPGA2
  • An CSC balance. Some of this CSC is set aside for the Reserve.
  • A sequence number, starting at 1 and increasing with each transaction sent from this account. No transaction can be included in a ledger unless the transaction's sequence number matches its sender's next sequence number.
  • A history of transactions that affected this account and its balances.
  • One or more ways to authorize transactions, possibly including:
    • A master key pair intrinsic to the account. (This can be disabled but not changed.)
    • A "regular" key pair that can be rotated.
    • A signer list for multi-signing. (Stored separately from the account's core data.)

In the ledger's data tree, an account's core data is stored in the AccountRoot ledger object type. An account can also be the owner (or partial owner) of several other types of data.

Tip: An "Account" in the CSC Ledger is somewhere between the financial usage (like "bank account") and the computing usage (like "UNIX account"). Non-CSC currencies and assets aren't stored in an CSC Ledger Account itself; each such asset is stored in an accounting relationship called a "Trust Line" that connects two parties.

Addresses

Accounts in the CSC Ledger are identified by a base58 CSC Ledger Address. The address is derived from the account's master public key, which is in turn derived from a secret key. An address is represented as a string in JSON and has the following characteristics:

  • Between 25 and 35 characters in length
  • Starts with the character c
  • Uses alphanumeric characters, excluding the number "0" capital letter "O", capital letter "I", and lowercase letter "l"
  • Case-sensitive
  • Includes a 4-byte checksum so that the probability of generating a valid address from random characters is approximately 1 in 2^32

Any valid address can become an account in the CSC Ledger by receiving a Payment of CSC, as long as the amount of CSC delivered is greater than or equal to the account reserve. This is called funding the account. You can also use an address that has not been funded to represent a regular key or a member of a signer list. Only a funded account can be the sender of a transaction.

Creating a valid address is a strictly mathematical task starting with a key pair. You can generate a key pair and calculate its address entirely offline without communicating to the CSC Ledger or any other party. The conversion from a public key to an address involves a one-way hash function, so it is possible to confirm that a public key matches an address but it is impossible to derive the public key from the address alone. (This is part of the reason why signed transactions include the public key and the address of the sender.)

For more technical details of how to calculate an CSC Ledger address, see Address Encoding.

Special Addresses

Some addresses have special meaning, or historical uses, in the CSC Ledger. In many cases, these are "black hole" addresses, meaning the address is not derived from a known secret key. Since it is effectively impossible to guess a secret key from only an address, any CSC possessed by black hole addresses is lost forever.

Address Name Meaning Black Hole?
rrrrrrrrrrrrrrrrrrrrrhoLvTp ACCOUNT_ZERO An address that is the base58 encoding of the value 0. In peer-to-peer communications, casinocoind uses this address as the issuer for CSC. Yes
rrrrrrrrrrrrrrrrrrrrBZbvji ACCOUNT_ONE An address that is the base58 encoding of the value 1. In the ledger, CasinocoinState entries use this address as a placeholder for the issuer of a trust line balance. Yes
cDarPNJEpCnpBZSfmcquydockkePkjPGA2 The genesis account When casinocoind starts a new genesis ledger from scratch (for example, in stand-alone mode), this account holds all the CSC. This address is generated from the seed value "masterpassphrase" which is hard-coded. No
rrrrrrrrrrrrrrrrrNAMEtxvNvQ CasinoCoin Name reservation black-hole In the past, CasinoCoin asked users to send CSC to this account to reserve CasinoCoin Names. Yes
rrrrrrrrrrrrrrrrrrrn5RM1rHd NaN Address Previous versions of casinocoin-libjs generated this address when base58 encoding the value NaN. Yes

Permanence of Accounts

Once created, an account exists in the CSC Ledger's data tree forever. This is because the current sequence number for a transaction must be tracked forever, so that old transactions cannot be processed a second time.

Unlike Bitcoin and many other crypto-currencies, each new version of the CSC Ledger's public ledger chain contains the full state of the ledger, which increases in size with each new account. For that reason, CasinoCoin discourages creating new accounts unless entirely necessary. Institutions who send and receive value on behalf of many users can use Source Tags and Destination Tags to distinguish payments from and to their customers while only using one (or a handful) of accounts in the CSC Ledger.

Transaction History

In the CSC Ledger, transaction history is tracked by a "thread" of transactions linked by a transaction's identifying hash and the ledger index. The AccountRoot ledger object has the identifying hash and ledger of the transaction that most recently modified it; the metadata of that transaction includes the previous state of the AccountRoot node, so it is possible to iterate through the history of a single account this way. This transaction history includes any transactions that modify the AccountRoot node directly, including:

  • Transactions sent by the account, because they modify the account's Sequence number. These transactions also modify the account's CSC balance because of the transaction cost.
  • Transactions that modified the account's CSC balance, including incoming Payment transactions and other types of transactions such as PaymentChannelClaim and EscrowFinish.

The conceptual transaction history of an account also includes transactions that modified the account's owned objects and non-CSC balances. These objects are separate ledger objects, each with their own thread of transactions that affected them. If you have an account's full ledger history, you can follow it forward to find the ledger objects created or modified by it. A "complete" transaction history includes the history of objects owned by a transaction, such as:

  • CasinocoinState objects (Trust Lines) connected to the account.
  • DirectoryNode objects, especially the owner directory tracking the account's owned objects.
  • Offer objects, representing the account's outstanding currency-exchange orders in the decentralized exchange
  • PayChannel objects, representing asynchronous payment channels to and from the account
  • Escrow objects, representing held payments to or from the account that are locked by time or a crypto-condition.
  • SignerList objects, representing lists of addresses that can authorize transactions for the account by multi-signing.

For more information on each of these objects, see the Ledger Format Reference.

Address Encoding

Tip: These technical details are only relevant for people building low-level library software for CSC Ledger compatibility!

[Source]

CSC Ledger addresses are encoded using base58 with the CasinoCoin dictionary: cpshnaf39wBUDNEGHJKLM4PQRST7VWXYZ2bcdeCg65jkm8oFqi1tuvAxyz. Since the CSC Ledger encodes several types of keys with base58, it prefixes the encoded data with a one-byte "type prefix" (also called a "version prefix") to distinguish them. The type prefix causes addresses to usually start with different letters in base58 format.

The following diagram shows the relationship between keys and addresses:

Passphrase → Secret Key → Public Key + Type Prefix → Account ID + Checksum → Address

The formula for calculating an CSC Ledger address is as follows. For the complete example code, see encode_address.js.

  1. Import required algorithms: SHA-256, RIPEMD160, and base58. Set the dictionary for base58.

    'use strict';
    const assert = require('assert');
    const crypto = require('crypto');
    const R_B58_DICT = 'cpshnaf39wBUDNEGHJKLM4PQRST7VWXYZ2bcdeCg65jkm8oFqi1tuvAxyz';
    const base58 = require('base-x')(R_B58_DICT);
    
    assert(crypto.getHashes().includes('sha256'));
    assert(crypto.getHashes().includes('ripemd160'));
    
  2. Start with a 33-byte ECDSA secp256k1 public key, or a 32-byte Ed25119 public key. For Ed25519 keys, prefix the key with the byte 0xED.

    const pubkey_hex =
      'ED9434799226374926EDA3B54B1B461B4ABF7237962EAE18528FEA67595397FA32';
    const pubkey = Buffer.from(pubkey_hex, 'hex');
    assert(pubkey.length == 33);
    
  3. Calculate the RIPEMD160 hash of the SHA-256 hash of the public key. This value is the "Account ID".

    const pubkey_inner_hash = crypto.createHash('sha256').update(pubkey);
    const pubkey_outer_hash = crypto.createHash('ripemd160');
    pubkey_outer_hash.update(pubkey_inner_hash.digest());
    const account_id = pubkey_outer_hash.digest();
    
  4. Calculate the SHA-256 hash of the SHA-256 hash of the Account ID; take the first 4 bytes. This value is the "checksum".

    const address_type_prefix = Buffer.from([0x00]);
    const payload = Buffer.concat([address_type_prefix, account_id]);
    const chksum_hash1 = crypto.createHash('sha256').update(payload).digest();
    const chksum_hash2 = crypto.createHash('sha256').update(chksum_hash1).digest();
    const checksum =  chksum_hash2.slice(0,4);
    
  5. Concatenate the payload and the checksum. Calculate the base58 value of the concatenated buffer. The result is the address.

    const dataToEncode = Buffer.concat([payload, checksum]);
    const address = base58.encode(dataToEncode);
    console.log(address);
    // cDTXLQ7ZKZVKz33zJbHjgVShjsBnqMBhmN