# Token-lending program A lending protocol for the Token program on the Solana blockchain inspired by Aave and Compound. # Public Keys for Port Finance ## Mainnet Lending Market: `6T4XxKerq744sSuj3jaoV6QiZ8acirf4TrPwQzHAoSy5` Lending program id: `port_variable_rate_lending_instructions::id()` Staking program id: `port_staking_instructions::id()` ### Reserve Public Keys | Asset Name | Reserve Address | | :--- | ----: | | SOL | X9ByyhmtQH3Wjku9N5obPy54DbVjZV7Z99TPJZ2rwcs | | USDC | DcENuKuYd6BWGhKfGr7eARxodqG12Bz1sN5WA8NwvLRx | | USDT | 4tqY9Hv7e8YhNQXuH75WKrZ7tTckbv2GfFVxmVcScW5s | | PAI | DSw99gXoGzvc4N7cNGU7TJ9bCWFq96NU2Cczi1TabDx2 | | SRM | ZgS3sv1tJAor2rbGMFLeJwxsEGDiHkcrR2ZaNHZUpyF | | BTC | DSST29PMCVkxo8cf5ht9LxrPoMc8jAZt98t6nuJywz8p | | MER | BnhsmYVvNjXK3TGDHLj1Yr1jBGCmD1gZMkAyCwoXsHwt | | mSOL | 9gDF5W94RowoDugxT8cM29cX8pKKQitTp2uYVrarBSQ7 | | pSOL | GRJyCEezbZQibAEfBKCRAg5YoTPP2UcRSTC7RfzoMypy | | SBR | 7dXHPrJtwBjQqU1pLKfkHbq9TjQAK9jTms3rnj1i3G77 | Actually all the information below you can get by parsing the reserve data. Here is provided for convenience. ### pToken Mint | Asset Name | pToken Mint | | :--- | ---: | | SOL | 8ezDtNNhX91t1NbSLe8xV2PcCEfoQjEm2qDVGjt3rjhg | | USDC | FgSsGV8GByPaMERxeQJPvZRZHf7zCBhrdYtztKorJS58 | | USDT | 3RudPTAkfcq9Q9Jk8SVeCoecCBmdKMj6q5smsWzxqtqZ | | PAI | GaqxUwFGGrDouYLqghchmZU97Y1rNhyF7noMTJNvpQPa | | SRM | 77TBgKmTNtMdGrt1ewNRb56F2Xw6fNLZZj33JZ3oGwXh | | BTC | QN2HkkBaWHfYSU5bybyups9z1UHu8Eu7QeeyMbjD2JA | | MER | 6UgGnLA3Lfe8NBLAESctsUXWdP3zjMFzSLEZxS3tiaKh | | mSOL | Dt1Cuau5m5CSmun8hZstjEh9RszxAmejnq7ZaHNcuXfA | | SBR | FhraFicS7fGxHn8jfzuZ6TeTpCu8PAnQNZiT2tqM5xvv| ### Oracle Public Keys | Asset Name | Oracle Pubkey | | :--- | ---: | | SOL | H6ARHf6YXhGYeQfUzQNGk6rDNnLBQKrenN712K4AQJEG | | USDC | N / A | | USDT | 3vxLXJqLqF3JG5TCbYycbKWRBbCJQLxQmBGCkyqEEefL | | PAI | N/A | | SRM | 3NBReDRTLKMQEKiLD5tGcx4kXbTf88b7f2xLS9UuGjym | | BTC | GVXRSBjFk6e6J3NbVPXohDJetcTjaeeuykUpbQF8UoMU | | MER | G4AQpTYKH1Fmg38VpFQbv6uKYQMpRhJzNPALhp7hqdrs | | pSOL | H6ARHf6YXhGYeQfUzQNGk6rDNnLBQKrenN712K4AQJEG | |SBR | 8Td9VML1nHxQK6M8VVyzsHo32D7VBk72jSpa9U861z2A| ### Supply Public Keys | Asset Name | Supply Public Keys | | :--- | ---: | | SOL | BLAFX12cDmsumyB6k3L6whJZqNqySaWeCmS5rVuzy3SS | | USDC | 2xPnqU4bWhUSjZ74CibY63NrtkHHw5eKntsxf8dzwiid | | USDT | QyvfrbqH7Mo8W5tHN31nzbfNiwFwqPqahjm9fnzo5EJ | | PAI | 42kNZrAuwZHLtuc7jvVX7zMfkfgwbPynqzFB3zdkAEGM | | SRM | DjhMNdgdbxNud1gmc4DUwrQqJxNbjhxiwNnhc4usSXmQ | | BTC | FZKP27Zxz9GbW86hhq3d1egzpBH5ZnYkyjQZVf86NQJ8 | | MER | 6UmrawFZgdPvMe6BLZdZCNRFz9u2TWsu5enFbTufA3a1 | |SBR| HTwd3VaDQphZgh2x7wqE2Qdndo4TT5C8fpvhKFcNh1Rt | ## Dev Net Lending Program id: `pdQ2rQQU5zH2rDgZ7xH2azMBJegUzUyunJ5Jd637hC4` Staking program id: `port_staking_instructions::id()` Lending Market: `H27Quk3DSbu55T4dCr1NddTTSAezXwHU67FPCZVKLhSW` ### Reserve Public Keys | Asset Name | Reserve Address | | :--- | ----: | | SOL | 6FeVStQAGPWvfWijDHF7cTWRCi7He6vTT3ubfNhe9SPt | | USDC | G1CcAWGhfxhHQaivC1Sh5CWVta6P4dc7a5BDSg9ERjV1 | | USDT | B4dnCXcWXSXy1g3fGAmF6P2XgsLTFYaQxYpsU3VCB33Q | | BTC | A8krqNC1WpWYhqUe2Y5WbLd1Zy4y2rRN5wJC8o9Scbyk | | MER | FdPnmYS7Ma8jfSy7UHAN5QM6teoqwd3vLQtoU6r2Umwy | Actually all the information below you can get by parsing the reserve data. Here is provided for convenience. ### Fake token Mint | Asset Name | pToken Mint | | :--- | ---: | | SOL | So11111111111111111111111111111111111111112 | | USDC | G6YKv19AeGZ6pUYUwY9D7n4Ry9ESNFa376YqwEkUkhbi | | USDT | 9NGDi2tZtNmCCp8SVLKNuGjuWAVwNF3Vap5tT8km5er9 | | BTC | EbwEYuUQHxcSHszxPBhA2nT2JxhiNwJedwjsctJnLmsC | | MER | Tm9LcR74uJHPw3zY3j3nSh5xfcyaLbvXgAtTJwbqnnp | ### pToken Mint | Asset Name | pToken Mint | | :--- | ---: | | SOL | Hk4Rp3kaPssB6hnjah3Mrqpt5CAXWGoqFT5dVsWA3TaM | | USDC | HyxraiKfdajDbYTC6MVRToEUBdevBN5M5gfyR4LC3WSF | | USDT | 4xEXmSfLFPkZaxdL98XkoxKpXEvchPVs21GYqa8DvbAm | | BTC | 95XGx3cM83Z1Bbx8pJurAHwxJjvShTJE4BtfgMWfV6NB | | MER | FQzruvtLTk6qtPNEAJHQWMVs4M9UMP9T3cGAVfUskHfP | ### Oracle Public Keys | Asset Name | Oracle Pubkey | | :--- | ---: | | SOL | J83w4HKfqxwcq3BEMMkPFSppX3gqekLyLJBexebFVkix | | USDC | N/A | | USDT | 38xoQ4oeJCBrcVvca2cGk7iV1dAfrmTR1kmhSCJQ8Jto | | BTC | HovQMDrbAgAYPCmHVSrezcSmkMtXSSUsLDFANExrZh2J | | MER | 6Z3ejn8DCWQFBuAcw29d3A5jgahEpmycn7YDMX7yRNrn | ### Supply Public Keys | Asset Name | Supply Public Keys | | :--- | ---: | | SOL | AbKeR7nQdHPDddiDQ71YUsz1F138a7cJMfJVtpdYUSvE | | USDC | GAPyFes3o7S7coY9nsuhaRZBEA7DdQPHBfVdY2DdgNua | | USDT | AeGbAqYZUURTykyCsgAUfopBMqQ3eAwrDxYhXoRhiw8q | | BTC | 75iyCxiPoj3MaUVo3SynmhaN3cbLDEhd4d9VHik6Kkvr | | MER | AMjhzse1TtTcKBFw5tQPLGtVoEsL4gt9YowNnzMKEGUr | ### Create StakeAccount For assets that have liquidity mining reward, you need first create a stake account in order to collateralize and get the reward. First, get the data of the reserve you want deposit into and unpack it to get the field `reserve.config.deposit_staking_pool` which is the staking pool id, and generates the seed and keypair by using the Solana built in `sha256` hashing function `solana_sdk::hash::hashv(&[owner.as_ref(), staking_pool.as_ref(), staking_program_id.as_ref()])`, where the owner should be your wallet's public key, and generate the keypair for stake account by `solana_sdk::signer::keypair::keypair_from_seed`. Then call `create_account` and `create_stake_account` instruction to create the stake account. Owner need to sign the instruction of claiming reward. If you are using a program to create the stake account, you can use an PDA account. Actually you can use any address to create the stake account, as long as you make sure that there is a one-one mapping between (owner, staking_pool) and stake_account, which means that for every owner and staking_pool, you only have one stake account. ```rust let account_seed = hashv( & [owner.as_ref(), staking_pool.as_ref(), staking_program_id.as_ref()]); let stake_account_key_pair = keypair_from_seed(account_seed.as_ref()).unwrap(); let instructions = vec![ create_account( &payer.pubkey(), &stake_account_key_pair.pubkey(), stake_account_rent, StakeAccount::LEN as u64, &staking_program_id ), create_stake_account( staking_program_id, stake_account_key_pair.pubkey(), staking_pool, owner ) ]; ``` ### Refresh Reserves and Obligation Assuming that you already have your stake account or you are depositing to a reserve without liquidity mining reward, you need refresh all the reserves the obligation has interacted with and the obligation itself in the same instruction before you depositing / withdrawing / repaying / liquidating. ```rust let mut refresh_instructions = vec![]; //reserve_map is a map of reserve pubkey of reserve data, you can get the oracle pubkey from the reserve data or can hard code it in a config file. let to_refresh = reserve_map.iter().filter( | (k, _) | { obligation .borrows .iter() .map(| li | li.borrow_reserve) .chain(obligation.deposits.iter().map(| ob | ob.deposit_reserve)) .any( | r | r == * * k) }); refresh_instructions.extend( to_refresh.map( | (k, v) | refresh_reserve(lending_program_id, * k, v.liquidity.oracle_pubkey)), ); refresh_instructions.push( refresh_obligation( program_id, obligation_pubkey, obligation .deposits .iter() .map(|d| d.deposit_reserve) .chain(obligation.borrows.iter().map(|b| b.borrow_reserve)) .collect(), ) ); ``` ### Initialize Obligation ```rust let mut transaction = Transaction::new_with_payer( &[ create_account( &payer.pubkey(), &obligation_keypair.pubkey(), rent.minimum_balance(Obligation::LEN), Obligation::LEN as u64, &port_finance_variable_rate_lending::id(), ), init_obligation( port_finance_variable_rate_lending::id(), obligation.pubkey, lending_market.pubkey, user_accounts_owner.pubkey(), ), ], Some( & payer.pubkey()), ); ``` ### Deposit Liquidity / Collateralize ```rust deposit_reserve_liquidity( port_variable_rate_lending::id(), liquidity_amount, user_liquidity_token_account_pubkey, user_collateral_token_account_pubkey, reserve_pubkey, reserve.liquidity.supply_pubkey, reserve.collateral.mint_pubkey, self.pubkey, user_transfer_authority.pubkey() ) ``` ```rust deposit_obligation_collateral( port_variable_rate_lending::id(), liquidity_amount, user_collateral_token_account_pubkey, reserve.collateral.supply_pubkey, reserve_pubkey, obligation_pubkey, lending_market.pubkey, obligation.owner, user_transfer_authority.pubkey(), Some(stake_account_pubkey), Some(staking_pool_pubkey), ) ``` ```rust deposit_reserve_liquidity_and_obligation_collateral( port_variable_rate_lending::id(), liquidity_amount, user_liquidity_token_account_pubkey, user_collateral_token_account_pubkey, reserve_pubkey, reserve.liquidity.supply_pubkey, reserve.collateral.mint_pubkey, lending_market_pubkey, reserve.collateral.supply_pubkey, obligation_pubkey, obligation.owner, user_transfer_authority.pubkey(), Some(stake_account_pubkey), Some(staking_pool_pubkey), ) ``` ### Withdraw There will be a coming `withdrawAndRedeem` instruction soon, while it is under auditing. So now, you need first uncollateralized the asset then withdraw. ```rust withdraw_obligation_collateral( port_finance_variable_rate_lending::id(), WITHDRAW_AMOUNT, reserve.collateral.supply_pubkey, sol_test_reserve.user_collateral_pubkey, sol_test_reserve.pubkey, test_obligation.pubkey, lending_market.pubkey, test_obligation.owner, Some(stake_account_pubkey), Some(staking_pool_pubkey), ) ``` ```rust redeem_reserve_collateral( port_finance_variable_rate_lending::id(), COLLATERAL_AMOUNT, user_collateral_token_account_pubkey, user_liquidity_token_account_pubkey, reserve_pubkey, reserve.collateral.mint_pubkey, reserve.liquidity.supply_pubkey, lending_market.pubkey, user_transfer_authority.pubkey(), ) ``` ### Repay To repay, you can pass number greater then amount you borrow to repay all, for example you can pass `u64::MAX` in to repay all. ```rust repay_obligation_liquidity( port_finance_variable_rate_lending::id(), liquidity_amount, user_liquidity_token_account_pubkey, reserve.liquidity.supply_pubkey, reserve_pubkey, obligation_pubkey, lending_market.pubkey, user_transfer_authority.pubkey(), ) ``` ### Liquidation Please refer to `https://github.com/port-finance/liquidator` ### Flashloan We had an instruction with the following signature for flash loan: ```rust pub enum LendingInstruction { // .... /// Make a flash loan. /// /// Accounts expected by this instruction: /// /// 0. `[writable]` Source liquidity token account. /// Minted by reserve liquidity mint. /// Must match the reserve liquidity supply. /// 1. `[writable]` Destination liquidity token account. /// Minted by reserve liquidity mint. /// 2. `[writable]` Reserve account. /// 3. `[]` Lending market account. /// 4. `[]` Derived lending market authority. /// 5. `[]` Flash loan receiver program account. /// Must implement an instruction that has tag of 0 and a signature of `(repay_amount: u64)` /// This instruction must return the amount to the source liquidity account. /// 6. `[]` Token program id. /// 7. `[writable]` Flash loan fee receiver account. /// Must match the reserve liquidity fee receiver. /// 8. `[writable]` Host fee receiver. /// .. `[any]` Additional accounts expected by the receiving program's `ReceiveFlashLoan` instruction. FlashLoan { /// The amount that is to be borrowed amount: u64, }, } ``` In the implementation, we do the following in order: 1. Perform safety checks and calculate fees 2. Transfer `amount` from the source liquidity account to the destination liquidity account 2. Call the `ReceiveFlashLoan` function (the flash loan receiver program is required to have this function with tag `0`). The additional account required for `ReceiveFlashLoan` is given from the 10th account of the `FlashLoan` instruction, i.e. after host fee receiver. 3. Check that the returned amount with the fee is in the reserve account after the completion of `ReceiveFlashLoan` function. The flash loan receiver program should have a `ReceiveFlashLoan` instruction which executes the user-defined operation and return the funds to the reserve in the end. ```rust pub enum FlashLoanReceiverInstruction { /// Receive a flash loan and perform user-defined operation and finally return the fund back. /// /// Accounts expected: /// /// 0. `[writable]` Source liquidity (matching the destination from above). /// 1. `[writable]` Destination liquidity (matching the source from above). /// 2. `[]` Token program id /// .. `[any]` Additional accounts provided to the lending program's `FlashLoan` instruction above. ReceiveFlashLoan { // Amount that is loaned to the receiver program amount: u64 } } ``` You can view a sample implementation [here](https://github.com/solana-labs/solana-program-library/tree/master/token-lending/program/tests/helpers/flash_loan_receiver.rs).