refactor: no assert in is_valid_impl(...) (#8397)

docs/docs/aztec/concepts/accounts/keys.md

@@ -129,7 +129,7 @@ Usually, an account contract will validate a signature of the incoming payload a
 
 This is a snippet of our Schnorr Account contract implementation, which uses Schnorr signatures for authentication:
 
-#include_code entrypoint /noir-projects/noir-contracts/contracts/schnorr_account_contract/src/main.nr rust
+#include_code is_valid_impl /noir-projects/noir-contracts/contracts/schnorr_account_contract/src/main.nr rust
 
 Still, different accounts may use different signing schemes, may require multi-factor authentication, or _may not even use signing keys_ and instead rely on other authentication mechanisms. Read [how to write an account contract](../../../tutorials/codealong/contract_tutorials/write_accounts_contract.md) for a full example of how to manage authentication.
 

noir-projects/noir-contracts/contracts/ecdsa_k_account_contract/src/main.nr

@@ -55,7 +55,9 @@ contract EcdsaKAccount {
         let public_key = storage.public_key.get_note();
 
         // Load auth witness
-        let witness: [Field; 64] = get_auth_witness(outer_hash);
+        let witness: [Field; 64] = unsafe {
+            get_auth_witness(outer_hash)
+        };
         let mut signature: [u8; 64] = [0; 64];
         for i in 0..64 {
             signature[i] = witness[i] as u8;
@@ -65,9 +67,6 @@ contract EcdsaKAccount {
         // Note that noir expects the hash of the message/challenge as input to the ECDSA verification.
         let outer_hash_bytes: [u8; 32] = outer_hash.to_be_bytes();
         let hashed_message: [u8; 32] = std::hash::sha256(outer_hash_bytes);
-        let verification = std::ecdsa_secp256k1::verify_signature(public_key.x, public_key.y, signature, hashed_message);
-        assert(verification == true);
-
-        true
+        std::ecdsa_secp256k1::verify_signature(public_key.x, public_key.y, signature, hashed_message)
     }
 }

noir-projects/noir-contracts/contracts/ecdsa_r_account_contract/src/main.nr

@@ -54,7 +54,9 @@ contract EcdsaRAccount {
         let public_key = storage.public_key.get_note();
 
         // Load auth witness
-        let witness: [Field; 64] = get_auth_witness(outer_hash);
+        let witness: [Field; 64] = unsafe {
+            get_auth_witness(outer_hash)
+        };
         let mut signature: [u8; 64] = [0; 64];
         for i in 0..64 {
             signature[i] = witness[i] as u8;
@@ -64,9 +66,6 @@ contract EcdsaRAccount {
         // Note that noir expects the hash of the message/challenge as input to the ECDSA verification.
         let outer_hash_bytes: [u8; 32] = outer_hash.to_be_bytes();
         let hashed_message: [u8; 32] = std::hash::sha256(outer_hash_bytes);
-        let verification = std::ecdsa_secp256r1::verify_signature(public_key.x, public_key.y, signature, hashed_message);
-        assert(verification == true);
-
-        true
+        std::ecdsa_secp256r1::verify_signature(public_key.x, public_key.y, signature, hashed_message)
     }
 }

noir-projects/noir-contracts/contracts/schnorr_account_contract/src/main.nr

@@ -18,9 +18,7 @@ contract SchnorrAccount {
 
     #[aztec(storage)]
     struct Storage {
-        // docs:start:storage
         signing_public_key: PrivateImmutable<PublicKeyNote>,
-        // docs:end:storage
     }
 
     // Constructs the contract
@@ -33,10 +31,8 @@ contract SchnorrAccount {
         // deploy this (typically MultiCallEntrypoint). I think it's ok here as I feel the outgoing here is not that
         // important.
 
-        // docs:start:initialize
         let mut pub_key_note = PublicKeyNote::new(signing_pub_key_x, signing_pub_key_y, this_keys.npk_m.hash());
         storage.signing_public_key.initialize(&mut pub_key_note).emit(encode_and_encrypt_note_with_keys(&mut context, this_keys.ovpk_m, this_keys.ivpk_m, this));
-        // docs:end:initialize
     }
 
     // Note: If you globally change the entrypoint signature don't forget to update account_entrypoint.ts file
@@ -57,29 +53,27 @@ contract SchnorrAccount {
 
     #[contract_library_method]
     fn is_valid_impl(context: &mut PrivateContext, outer_hash: Field) -> bool {
-        // docs:start:entrypoint
+        // docs:start:is_valid_impl
         // Load public key from storage
         let storage = Storage::init(context);
-        // docs:start:get_note
         let public_key = storage.signing_public_key.get_note();
-        // docs:end:get_note
         // Load auth witness
-        let witness: [Field; 64] = get_auth_witness(outer_hash);
+        let witness: [Field; 64] = unsafe {
+            get_auth_witness(outer_hash)
+        };
         let mut signature: [u8; 64] = [0; 64];
         for i in 0..64 {
             signature[i] = witness[i] as u8;
         }
 
         // Verify signature of the payload bytes
-        let verification = std::schnorr::verify_signature(
+        std::schnorr::verify_signature(
             public_key.x,
             public_key.y,
             signature,
             outer_hash.to_be_bytes::<32>()
-        );
-        assert(verification == true);
-        // docs:end:entrypoint
-        true
+        )
+        // docs:end:is_valid_impl
     }
 
     /**

noir-projects/noir-contracts/contracts/schnorr_hardcoded_account_contract/src/main.nr

@@ -1,9 +1,7 @@
 // docs:start:contract
 // Account contract that uses Schnorr signatures for authentication using a hardcoded public key.
 contract SchnorrHardcodedAccount {
-    use dep::std;
     use dep::aztec::prelude::PrivateContext;
-
     use dep::authwit::{
         entrypoint::{app::AppPayload, fee::FeePayload}, account::AccountActions,
         auth_witness::get_auth_witness
@@ -30,21 +28,21 @@ contract SchnorrHardcodedAccount {
     #[contract_library_method]
     fn is_valid_impl(_context: &mut PrivateContext, outer_hash: Field) -> bool {
         // Load auth witness and format as an u8 array
-        let witness: [Field; 64] = get_auth_witness(outer_hash);
+        let witness: [Field; 64] = unsafe {
+            get_auth_witness(outer_hash)
+        };
         let mut signature: [u8; 64] = [0; 64];
         for i in 0..64 {
             signature[i] = witness[i] as u8;
         }
 
         // Verify signature using hardcoded public key
-        let verification = std::schnorr::verify_signature(
+        std::schnorr::verify_signature(
             public_key_x,
             public_key_y,
             signature,
             outer_hash.to_be_bytes::<32>()
-        );
-        assert(verification == true);
-        true
+        )
     }
     // docs:end:is-valid
 }

noir-projects/noir-contracts/contracts/schnorr_single_key_account_contract/src/main.nr

@@ -2,7 +2,7 @@ mod util;
 mod auth_oracle;
 
 contract SchnorrSingleKeyAccount {
-    use dep::aztec::prelude::{AztecAddress, FunctionSelector, PrivateContext};
+    use dep::aztec::prelude::PrivateContext;
 
     use dep::authwit::{entrypoint::{app::AppPayload, fee::FeePayload}, account::AccountActions};
 
@@ -24,8 +24,9 @@ contract SchnorrSingleKeyAccount {
 
     #[contract_library_method]
     fn is_valid_impl(context: &mut PrivateContext, outer_hash: Field) -> bool {
-        let witness = get_auth_witness(outer_hash);
-        assert(recover_address(outer_hash, witness).eq(context.this_address()));
-        true
+        let witness = unsafe {
+            get_auth_witness(outer_hash)
+        };
+        recover_address(outer_hash, witness).eq(context.this_address())
     }
 }