Fix vote program bugs

Also:

* Add an assertion to the transaction builder if not enough
keypairs were provided for all keys that require signatures.
* Expose bugs in the runtime.

programs/native/vote/src/lib.rs

@@ -21,12 +21,6 @@ fn entrypoint(
     trace!("process_instruction: {:?}", data);
     trace!("keyed_accounts: {:?}", keyed_accounts);
 
-    // all vote instructions require that accounts_keys[0] be a signer
-    if keyed_accounts[0].signer_key().is_none() {
-        error!("account[0] is unsigned");
-        Err(ProgramError::InvalidArgument)?;
-    }
-
     match deserialize(data).map_err(|_| ProgramError::InvalidUserdata)? {
         VoteInstruction::InitializeAccount => vote_program::initialize_account(keyed_accounts),
         VoteInstruction::DelegateStake(delegate_id) => {

programs/native/vote/tests/vote.rs

@@ -0,0 +1,100 @@
+//use solana_runtime::bank::BankError;
+use solana_runtime::bank::{Bank, Result};
+use solana_sdk::genesis_block::GenesisBlock;
+use solana_sdk::hash::hash;
+//use solana_sdk::native_program::ProgramError;
+use solana_sdk::pubkey::Pubkey;
+use solana_sdk::signature::{Keypair, KeypairUtil};
+use solana_sdk::system_instruction::SystemInstruction;
+use solana_sdk::transaction_builder::{BuilderInstruction, TransactionBuilder};
+use solana_sdk::vote_program::{self, Vote, VoteInstruction, VoteState};
+use solana_sdk::vote_transaction::VoteTransaction;
+
+struct VoteBank<'a> {
+    bank: &'a Bank,
+}
+
+impl<'a> VoteBank<'a> {
+    fn new(bank: &'a Bank) -> Self {
+        bank.add_native_program("solana_vote_program", &vote_program::id());
+        Self { bank }
+    }
+
+    fn create_vote_account(
+        &self,
+        from_keypair: &Keypair,
+        vote_id: Pubkey,
+        lamports: u64,
+    ) -> Result<()> {
+        let last_id = self.bank.last_id();
+        let tx = VoteTransaction::fund_staking_account(from_keypair, vote_id, last_id, lamports, 0);
+        self.bank.process_transaction(&tx)
+    }
+
+    fn submit_vote(&self, vote_keypair: &Keypair, tick_height: u64) -> Result<VoteState> {
+        let last_id = self.bank.last_id();
+        let tx = VoteTransaction::new_vote(vote_keypair, tick_height, last_id, 0);
+        self.bank.process_transaction(&tx)?;
+        self.bank.register_tick(&hash(last_id.as_ref()));
+
+        let vote_account = self.bank.get_account(&vote_keypair.pubkey()).unwrap();
+        Ok(VoteState::deserialize(&vote_account.userdata).unwrap())
+    }
+}
+
+#[test]
+fn test_vote_via_bank() {
+    let (genesis_block, from_keypair) = GenesisBlock::new(10_000);
+    let bank = Bank::new(&genesis_block);
+    let vote_bank = VoteBank::new(&bank);
+
+    let vote_keypair = Keypair::new();
+    let vote_id = vote_keypair.pubkey();
+    vote_bank
+        .create_vote_account(&from_keypair, vote_id, 100)
+        .unwrap();
+
+    let vote_state = vote_bank.submit_vote(&vote_keypair, 0).unwrap();
+    assert_eq!(vote_state.votes.len(), 1);
+}
+
+#[test]
+fn test_vote_via_bank_with_no_signature() {
+    let (genesis_block, mallory_keypair) = GenesisBlock::new(10_000);
+    let bank = Bank::new(&genesis_block);
+    let vote_bank = VoteBank::new(&bank);
+
+    let vote_keypair = Keypair::new();
+    let vote_id = vote_keypair.pubkey();
+    vote_bank
+        .create_vote_account(&mallory_keypair, vote_id, 100)
+        .unwrap();
+
+    let mallory_id = mallory_keypair.pubkey();
+    let last_id = bank.last_id();
+    let vote_ix = BuilderInstruction::new(
+        vote_program::id(),
+        &VoteInstruction::Vote(Vote::new(0)),
+        vec![(vote_id, false)], // <--- attack!! No signature.
+    );
+
+    // Sneak in an instruction so that the transaction is signed but
+    // the 0th account in the second instruction is not! The program
+    // needs to check that it's signed.
+    let tx = TransactionBuilder::default()
+        .push(SystemInstruction::new_move(mallory_id, vote_id, 1))
+        .push(vote_ix)
+        .sign(&[&mallory_keypair], last_id);
+
+    let _result = bank.process_transaction(&tx);
+
+    // And ensure there's no vote.
+    let vote_account = bank.get_account(&vote_id).unwrap();
+    let vote_state = VoteState::deserialize(&vote_account.userdata).unwrap();
+    assert_eq!(vote_state.votes.len(), 0);
+
+    //assert_eq!(
+    //    result,
+    //    Err(BankError::ProgramError(1, ProgramError::InvalidArgument))
+    //);
+}