fix: Remove caller ID workaround for root contexts

miden-lib/asm/kernels/transaction/lib/account.masm

@@ -528,12 +528,6 @@ end
 #! Panics if
 #! - index is out of bounds
 export.get_procedure_info
-  # TODO: Fix VM caller == [0,0,0,0] bug and remove this check
-  # check if index == 255
-  dup push.255 neq
-  # => [is_255, index]
-
-  if.true
     # check that index < number of procedures contained in the account code
     dup exec.memory::get_num_account_procedures lt assert.err=ERR_PROC_INDEX_OUT_OF_BOUNDS
     # => [index]
@@ -545,7 +539,6 @@ export.get_procedure_info
     # load procedure information from memory
     mem_load swap padw movup.4 mem_loadw
     # => [PROC_ROOT, storage_offset]
-  end
  end
 
 #! Verifies that the procedure root is part of the account code
@@ -563,26 +556,13 @@ export.authenticate_procedure
     emit.ACCOUNT_PUSH_PROCEDURE_INDEX_EVENT adv_push.1
     # => [index, PROC_ROOT]
 
-    # get procedure info (PROC_ELEMENTS, storage_offset) from memory stored at index
+    # get procedure info (PROC_ROOT, storage_offset) from memory stored at index
     exec.get_procedure_info
-    # In production:
-    # => [PROC_ELEMENTS, storage_offset, PROC_ROOT]
-    # During testing:
-    # => [255, PROC_ROOT]
-
-    # TODO: Fix VM caller == [0,0,0,0] bug and remove this check
-    # check if get_procedure_info returned 255
-    dup push.255 neq
-    # => [is_255, index, PROC_ROOT]
-
-    if.true
-      # verify that PROC_ROOT exists in memory at index
-      movup.4 movdn.8 assert_eqw.err=ERR_PROC_NOT_PART_OF_ACCOUNT_CODE
-      # => [storage_offset]
-    else
-      # drop PROC_ROOT
-      movdn.4 dropw drop push.0
-    end
+    # => [PROC_ROOT, storage_offset, PROC_ROOT]
+
+    # verify that PROC_ROOT exists in memory at index
+    movup.4 movdn.8 assert_eqw.err=ERR_PROC_NOT_PART_OF_ACCOUNT_CODE
+    # => [storage_offset]
 end
 
 #! Validates that the account seed, provided via the advice map, satisfies the seed requirements.

miden-lib/asm/kernels/transaction/lib/prologue.masm

@@ -352,7 +352,8 @@ proc.validate_new_account
 
         if.true
             # assert the fungible faucet reserved slot is initialized correctly (EMPTY_WORD)
-            or or or assertz.err=ERR_PROLOGUE_NEW_FUNGIBLE_FAUCET_NON_EMPTY_RESERVED_SLOT
+            # TODO: Switch to standard library implementation when available (miden-vm/#1483)
+            exec.is_empty_word_dropped not assertz.err=ERR_PROLOGUE_NEW_FUNGIBLE_FAUCET_NON_EMPTY_RESERVED_SLOT
             # => []
 
             # get the faucet reserved storage data slot type and entry arity
@@ -368,6 +369,7 @@ proc.validate_new_account
             # empty SMT)
             exec.constants::get_empty_smt_root assert_eqw.err=ERR_PROLOGUE_NEW_NON_FUNGIBLE_FAUCET_INVALID_RESERVED_SLOT
             # => []
+            push.1001 drop                              # TODO: remove line, see miden-vm/#1122
 
             # get the faucet reserved storage data slot type and entry arity
             exec.account::get_faucet_storage_data_slot exec.account::get_storage_slot_type_info
@@ -390,6 +392,19 @@ proc.validate_new_account
     # => []
 end
 
+#! Returns whether the input word is equal to EMPTY_WORD as a boolean value.
+#!
+#! This procedure drops the input word.
+#! Stack: [INPUT_WORD]
+#! Output: [is_empty]
+#!
+#! Where:
+#! - INPUT_WORD is the word is compared with EMPTY_WORD.
+#! - is_empty is a boolean value that is 1 if INPUT_WORD is equal to EMPTY_WORD, and 0 otherwise.
+proc.is_empty_word_dropped
+    eq.0 swap eq.0 and swap eq.0 and swap eq.0 and
+end
+
 #! Validates that account procedures match account code commitment and saves procedure information
 #! into memory.
 #!

miden-lib/src/transaction/mod.rs

@@ -285,6 +285,7 @@ impl TransactionKernel {
     pub fn testing_assembler_with_mock_account() -> Assembler {
         let assembler = Self::testing_assembler();
         let library = AccountCode::mock_library(assembler.clone());
+
         assembler.with_library(library).expect("failed to add mock account code")
     }
 }

miden-tx/src/auth/tx_authenticator.rs

@@ -6,7 +6,7 @@ use rand::Rng;
 use vm_processor::{Digest, Felt, Word};
 
 use super::signatures::get_falcon_signature;
-use crate::error::AuthenticationError;
+use crate::errors::AuthenticationError;
 
 // TRANSACTION AUTHENTICATOR
 // ================================================================================================