program: map pubkey err to customs (#45)

program/src/error.rs

@@ -6,13 +6,26 @@ use {
         decode_error::DecodeError,
         msg,
         program_error::{PrintProgramError, ProgramError},
+        pubkey::PubkeyError,
     },
     thiserror::Error,
 };
 
 /// Errors that can be returned by the Config program.
 #[derive(Error, Clone, Debug, Eq, PartialEq, FromPrimitive)]
 pub enum AddressLookupTableError {
+    // Reimplementations of `PubkeyError` variants.
+    //
+    // Required for the BPF version since the Agave SDK only maps `PubkeyError`
+    // to `ProgramError`, not `InstructionError`. Therefore, the builtin
+    // version throws unknown custom error codes (0x0 - 0x2).
+    /// Length of the seed is too long for address generation
+    #[error("Length of the seed is too long for address generation")]
+    PubkeyErrorMaxSeedLengthExceeded = 0,
+    #[error("Provided seeds do not result in a valid address")]
+    PubkeyErrorInvalidSeeds,
+    #[error("Provided owner is not allowed")]
+    PubkeyErrorIllegalOwner,
     /// Instruction modified data of a read-only account.
     #[error("Instruction modified data of a read-only account")]
     ReadonlyDataModified = 10, // Avoid collisions with System.
@@ -35,3 +48,15 @@ impl<T> DecodeError<T> for AddressLookupTableError {
         "AddressLookupTableError"
     }
 }
+
+impl From<PubkeyError> for AddressLookupTableError {
+    fn from(e: PubkeyError) -> Self {
+        match e {
+            PubkeyError::MaxSeedLengthExceeded => {
+                AddressLookupTableError::PubkeyErrorMaxSeedLengthExceeded
+            }
+            PubkeyError::InvalidSeeds => AddressLookupTableError::PubkeyErrorInvalidSeeds,
+            PubkeyError::IllegalOwner => AddressLookupTableError::PubkeyErrorIllegalOwner,
+        }
+    }
+}

program/src/processor.rs

@@ -158,7 +158,8 @@ fn process_create_lookup_table(
         &derivation_slot.to_le_bytes(),
         &[bump_seed],
     ];
-    let derived_table_key = Pubkey::create_program_address(derived_table_seeds, program_id)?;
+    let derived_table_key = Pubkey::create_program_address(derived_table_seeds, program_id)
+        .map_err(AddressLookupTableError::from)?;
 
     if lookup_table_info.key != &derived_table_key {
         msg!(