Runtime: Core BPF Migration: Struct for loading and checking source B…

…PF program accounts (solana-labs#332)

* runtime: core_bpf_migration: add source_bpf_upgradeable config

* runtime: core_bpf_migration: add source_bpf_upgradeable config tests

* renamings

* bincode error

* drop `total_size`

runtime/src/bank/builtins/core_bpf_migration/error.rs

@@ -1,8 +1,11 @@
 use {solana_sdk::pubkey::Pubkey, thiserror::Error};
 
 /// Errors returned by a Core BPF migration.
-#[derive(Debug, Error, PartialEq)]
+#[derive(Debug, Error)]
 pub enum CoreBpfMigrationError {
+    /// Bincode serialization error
+    #[error("Bincode serialization error: {0:?}")]
+    BincodeError(#[from] bincode::Error),
     /// Account not found
     #[error("Account not found: {0:?}")]
     AccountNotFound(Pubkey),
@@ -15,4 +18,16 @@ pub enum CoreBpfMigrationError {
     /// Program has a data account
     #[error("Data account exists for program {0:?}")]
     ProgramHasDataAccount(Pubkey),
+    /// Program has no data account
+    #[error("Data account does not exist for program {0:?}")]
+    ProgramHasNoDataAccount(Pubkey),
+    /// Invalid program account
+    #[error("Invalid program account: {0:?}")]
+    InvalidProgramAccount(Pubkey),
+    /// Invalid program data account
+    #[error("Invalid program data account: {0:?}")]
+    InvalidProgramDataAccount(Pubkey),
+    /// Arithmetic overflow
+    #[error("Arithmetic overflow")]
+    ArithmeticOverflow,
 }

runtime/src/bank/builtins/core_bpf_migration/mod.rs

@@ -1,5 +1,6 @@
 #![allow(dead_code)] // Removed in later commit
 pub(crate) mod error;
+mod source_upgradeable_bpf;
 mod target_builtin;
 
 pub(crate) enum CoreBpfMigrationTargetType {

runtime/src/bank/builtins/core_bpf_migration/source_upgradeable_bpf.rs

@@ -0,0 +1,348 @@
+use {
+    super::error::CoreBpfMigrationError,
+    crate::bank::Bank,
+    solana_sdk::{
+        account::{AccountSharedData, ReadableAccount},
+        bpf_loader_upgradeable::{
+            get_program_data_address, UpgradeableLoaderState, ID as BPF_LOADER_UPGRADEABLE_ID,
+        },
+        pubkey::Pubkey,
+    },
+};
+
+/// The account details of an Upgradeable BPF program slated to replace a
+/// built-in program.
+#[derive(Debug)]
+pub(crate) struct SourceUpgradeableBpf {
+    pub program_address: Pubkey,
+    pub program_account: AccountSharedData,
+    pub program_data_address: Pubkey,
+    pub program_data_account: AccountSharedData,
+}
+
+impl SourceUpgradeableBpf {
+    fn check_program_account(&self) -> Result<(), CoreBpfMigrationError> {
+        // The program account should be owned by the upgradeable loader.
+        if self.program_account.owner() != &BPF_LOADER_UPGRADEABLE_ID {
+            return Err(CoreBpfMigrationError::IncorrectOwner(self.program_address));
+        }
+
+        // The program account should have a pointer to its data account.
+        if let UpgradeableLoaderState::Program {
+            programdata_address,
+        } = &self.program_account.deserialize_data()?
+        {
+            if programdata_address != &self.program_data_address {
+                return Err(CoreBpfMigrationError::InvalidProgramAccount(
+                    self.program_address,
+                ));
+            }
+        }
+
+        Ok(())
+    }
+
+    fn check_program_data_account(&self) -> Result<(), CoreBpfMigrationError> {
+        // The program data account should be owned by the upgradeable loader.
+        if self.program_data_account.owner() != &BPF_LOADER_UPGRADEABLE_ID {
+            return Err(CoreBpfMigrationError::IncorrectOwner(
+                self.program_data_address,
+            ));
+        }
+
+        // The program data account should have the correct state.
+        let programdata_data_offset = UpgradeableLoaderState::size_of_programdata_metadata();
+        if self.program_data_account.data().len() < programdata_data_offset {
+            return Err(CoreBpfMigrationError::InvalidProgramDataAccount(
+                self.program_data_address,
+            ));
+        }
+        // Length checked in previous block.
+        match bincode::deserialize::<UpgradeableLoaderState>(
+            &self.program_data_account.data()[..programdata_data_offset],
+        )? {
+            UpgradeableLoaderState::ProgramData { .. } => Ok(()),
+            _ => Err(CoreBpfMigrationError::InvalidProgramDataAccount(
+                self.program_data_address,
+            )),
+        }
+    }
+
+    /// Collects the details of an upgradeable BPF program and verifies it is
+    /// properly configured.
+    /// The program account should exist with a pointer to its data account.
+    /// The program data account should exist with the correct state
+    /// (a ProgramData header and the program ELF).
+    pub(crate) fn new_checked(
+        bank: &Bank,
+        program_address: &Pubkey,
+    ) -> Result<Self, CoreBpfMigrationError> {
+        // The program account should exist.
+        let program_account = bank
+            .get_account_with_fixed_root(program_address)
+            .ok_or(CoreBpfMigrationError::AccountNotFound(*program_address))?;
+
+        // The program data account should exist.
+        let program_data_address = get_program_data_address(program_address);
+        let program_data_account = bank
+            .get_account_with_fixed_root(&program_data_address)
+            .ok_or(CoreBpfMigrationError::ProgramHasNoDataAccount(
+                *program_address,
+            ))?;
+
+        let source_upgradeable_bpf = Self {
+            program_address: *program_address,
+            program_account,
+            program_data_address,
+            program_data_account,
+        };
+
+        source_upgradeable_bpf.check_program_account()?;
+        source_upgradeable_bpf.check_program_data_account()?;
+
+        Ok(source_upgradeable_bpf)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use {
+        super::*,
+        crate::bank::tests::create_simple_test_bank,
+        assert_matches::assert_matches,
+        solana_sdk::{account::Account, bpf_loader_upgradeable::ID as BPF_LOADER_UPGRADEABLE_ID},
+    };
+
+    fn store_account<T: serde::Serialize>(
+        bank: &Bank,
+        address: &Pubkey,
+        data: &T,
+        additional_data: Option<&[u8]>,
+        executable: bool,
+        owner: &Pubkey,
+    ) {
+        let mut data = bincode::serialize(data).unwrap();
+        if let Some(additional_data) = additional_data {
+            data.extend_from_slice(additional_data);
+        }
+        let data_len = data.len();
+        let lamports = bank.get_minimum_balance_for_rent_exemption(data_len);
+        let account = AccountSharedData::from(Account {
+            data,
+            executable,
+            lamports,
+            owner: *owner,
+            ..Account::default()
+        });
+        bank.store_account_and_update_capitalization(address, &account);
+    }
+
+    #[test]
+    fn test_source_upgradeable_bpf() {
+        let bank = create_simple_test_bank(0);
+
+        let program_id = Pubkey::new_unique();
+        let program_data_address = get_program_data_address(&program_id);
+
+        // Fail if the program account does not exist
+        assert_matches!(
+            SourceUpgradeableBpf::new_checked(&bank, &program_id).unwrap_err(),
+            CoreBpfMigrationError::AccountNotFound(..)
+        );
+
+        // Store the proper program account
+        let proper_program_account_state = UpgradeableLoaderState::Program {
+            programdata_address: program_data_address,
+        };
+        store_account(
+            &bank,
+            &program_id,
+            &proper_program_account_state,
+            None,
+            true,
+            &BPF_LOADER_UPGRADEABLE_ID,
+        );
+
+        // Fail if the program data account does not exist
+        assert_matches!(
+            SourceUpgradeableBpf::new_checked(&bank, &program_id).unwrap_err(),
+            CoreBpfMigrationError::ProgramHasNoDataAccount(..)
+        );
+
+        // Store the proper program data account
+        let proper_program_data_account_state = UpgradeableLoaderState::ProgramData {
+            slot: 0,
+            upgrade_authority_address: Some(Pubkey::new_unique()),
+        };
+        store_account(
+            &bank,
+            &program_data_address,
+            &proper_program_data_account_state,
+            Some(&[4u8; 200]),
+            false,
+            &BPF_LOADER_UPGRADEABLE_ID,
+        );
+
+        // Success
+        let source_upgradeable_bpf = SourceUpgradeableBpf::new_checked(&bank, &program_id).unwrap();
+
+        let check_program_account_data = bincode::serialize(&proper_program_account_state).unwrap();
+        let check_program_account_data_len = check_program_account_data.len();
+        let check_program_lamports =
+            bank.get_minimum_balance_for_rent_exemption(check_program_account_data_len);
+        let check_program_account = AccountSharedData::from(Account {
+            data: check_program_account_data,
+            executable: true,
+            lamports: check_program_lamports,
+            owner: BPF_LOADER_UPGRADEABLE_ID,
+            ..Account::default()
+        });
+
+        let mut check_program_data_account_data =
+            bincode::serialize(&proper_program_data_account_state).unwrap();
+        check_program_data_account_data.extend_from_slice(&[4u8; 200]);
+        let check_program_data_account_data_len = check_program_data_account_data.len();
+        let check_program_data_lamports =
+            bank.get_minimum_balance_for_rent_exemption(check_program_data_account_data_len);
+        let check_program_data_account = AccountSharedData::from(Account {
+            data: check_program_data_account_data,
+            executable: false,
+            lamports: check_program_data_lamports,
+            owner: BPF_LOADER_UPGRADEABLE_ID,
+            ..Account::default()
+        });
+
+        assert_eq!(source_upgradeable_bpf.program_address, program_id);
+        assert_eq!(
+            source_upgradeable_bpf.program_account,
+            check_program_account
+        );
+        assert_eq!(
+            source_upgradeable_bpf.program_data_address,
+            program_data_address
+        );
+        assert_eq!(
+            source_upgradeable_bpf.program_data_account,
+            check_program_data_account
+        );
+    }
+
+    #[test]
+    fn test_source_upgradeable_bpf_bad_program_account() {
+        let bank = create_simple_test_bank(0);
+
+        let program_id = Pubkey::new_unique();
+        let program_data_address = get_program_data_address(&program_id);
+
+        // Store the proper program data account
+        store_account(
+            &bank,
+            &program_data_address,
+            &UpgradeableLoaderState::ProgramData {
+                slot: 0,
+                upgrade_authority_address: Some(Pubkey::new_unique()),
+            },
+            Some(&[4u8; 200]),
+            false,
+            &BPF_LOADER_UPGRADEABLE_ID,
+        );
+
+        // Fail if the program account is not owned by the upgradeable loader
+        store_account(
+            &bank,
+            &program_id,
+            &UpgradeableLoaderState::Program {
+                programdata_address: program_data_address,
+            },
+            None,
+            true,
+            &Pubkey::new_unique(), // Not the upgradeable loader
+        );
+        assert_matches!(
+            SourceUpgradeableBpf::new_checked(&bank, &program_id).unwrap_err(),
+            CoreBpfMigrationError::IncorrectOwner(..)
+        );
+
+        // Fail if the program account's state is not `UpgradeableLoaderState::Program`
+        store_account(
+            &bank,
+            &program_id,
+            &vec![0u8; 200],
+            None,
+            true,
+            &BPF_LOADER_UPGRADEABLE_ID,
+        );
+        assert_matches!(
+            SourceUpgradeableBpf::new_checked(&bank, &program_id).unwrap_err(),
+            CoreBpfMigrationError::BincodeError(..)
+        );
+
+        // Fail if the program account's state is `UpgradeableLoaderState::Program`,
+        // but it points to the wrong data account
+        store_account(
+            &bank,
+            &program_id,
+            &UpgradeableLoaderState::Program {
+                programdata_address: Pubkey::new_unique(), // Not the correct data account
+            },
+            None,
+            true,
+            &BPF_LOADER_UPGRADEABLE_ID,
+        );
+        assert_matches!(
+            SourceUpgradeableBpf::new_checked(&bank, &program_id).unwrap_err(),
+            CoreBpfMigrationError::InvalidProgramAccount(..)
+        );
+    }
+
+    #[test]
+    fn test_source_upgradeable_bpf_bad_program_data_account() {
+        let bank = create_simple_test_bank(0);
+
+        let program_id = Pubkey::new_unique();
+        let program_data_address = get_program_data_address(&program_id);
+
+        // Store the proper program account
+        store_account(
+            &bank,
+            &program_id,
+            &UpgradeableLoaderState::Program {
+                programdata_address: program_data_address,
+            },
+            None,
+            true,
+            &BPF_LOADER_UPGRADEABLE_ID,
+        );
+
+        // Fail if the program data account is not owned by the upgradeable loader
+        store_account(
+            &bank,
+            &program_data_address,
+            &UpgradeableLoaderState::ProgramData {
+                slot: 0,
+                upgrade_authority_address: Some(Pubkey::new_unique()),
+            },
+            Some(&[4u8; 200]),
+            false,
+            &Pubkey::new_unique(), // Not the upgradeable loader
+        );
+        assert_matches!(
+            SourceUpgradeableBpf::new_checked(&bank, &program_id).unwrap_err(),
+            CoreBpfMigrationError::IncorrectOwner(..)
+        );
+
+        // Fail if the program data account does not have the correct state
+        store_account(
+            &bank,
+            &program_data_address,
+            &vec![4u8; 200], // Not the correct state
+            None,
+            false,
+            &BPF_LOADER_UPGRADEABLE_ID,
+        );
+        assert_matches!(
+            SourceUpgradeableBpf::new_checked(&bank, &program_id).unwrap_err(),
+            CoreBpfMigrationError::BincodeError(..)
+        );
+    }
+}