Check that the program was granted access to program_id (#13890)

programs/bpf/rust/caller_access/src/lib.rs

@@ -0,0 +1,52 @@
+use solana_program::{
+    account_info::AccountInfo,
+    entrypoint,
+    entrypoint::ProgramResult,
+    instruction::{AccountMeta, Instruction},
+    msg,
+    program::invoke,
+    pubkey::Pubkey,
+};
+use std::convert::TryInto;
+
+entrypoint!(process_instruction);
+fn process_instruction(
+    program_id: &Pubkey,
+    accounts: &[AccountInfo],
+    instruction_data: &[u8],
+) -> ProgramResult {
+    if instruction_data.len() == 32 {
+        let key = Pubkey::new_from_array(instruction_data.try_into().unwrap());
+        let ix = Instruction::new(key, &[2], vec![]);
+        let mut lamports = accounts[0].lamports();
+        let owner = &accounts[0].owner;
+        let mut data = accounts[0].try_borrow_mut_data()?;
+        let account = AccountInfo::new(
+            &key,
+            false,
+            false,
+            &mut lamports,
+            &mut data,
+            &owner,
+            true,
+            0,
+        );
+        msg!("{:?} calling {:?}", program_id, key);
+        invoke(&ix, &[account])?;
+    } else {
+        match instruction_data[0] {
+            1 => {
+                let ix = Instruction::new(
+                    *program_id,
+                    &accounts[1].key.to_bytes(),
+                    vec![AccountMeta::new_readonly(*program_id, false)],
+                );
+                msg!("{:?} calling {:?}", program_id, program_id);
+                invoke(&ix, accounts)?;
+            }
+
+            _ => msg!("Should never get here"),
+        }
+    }
+    Ok(())
+}