feat: use assert safe from utu

Scarb.toml

@@ -7,9 +7,9 @@ edition = "2023_11"
 
 [dependencies]
 starknet = "2.8.4"
-utils = { git = "https://github.com/keep-starknet-strange/raito.git" }
-consensus = { git = "https://github.com/keep-starknet-strange/raito.git" }
-utu_relay = { git = "https://github.com/lfglabs-dev/utu_relay.git" }
+utils = { git = "https://github.com/keep-starknet-strange/raito.git", rev = "02a13045b7074ae2b3247431cd91f1ad76263fb2" }
+consensus = { git = "https://github.com/keep-starknet-strange/raito.git", rev = "02a13045b7074ae2b3247431cd91f1ad76263fb2" }
+utu_relay = { git = "https://github.com/lfglabs-dev/utu_relay.git", rev = "80dd830" }
 
 [dev-dependencies]
 snforge_std = { git = "https://github.com/foundry-rs/starknet-foundry", tag = "v0.31.0" }

src/lib.cairo

@@ -74,13 +74,11 @@ mod BitcoinDepositor {
             assert(
                 block_header.merkle_root_hash.value == merkle_root.value, 'invalid inclusion proof'
             );
-            // we verify this block is part of the canonical chain
-            let utu = IUtuRelayDispatcher { contract_address: self.utu_address.read() };
-            let canonical_block_digest = utu.get_block(block_height);
-            assert(canonical_block_digest == block_header.hash(), 'invalid block digest');
 
-            // in case we want to check the status
-            // let block_status = utu.get_status(canonical_block_digest);
+            // we verify this block is safe to use (part of the canonical chain & sufficient pow)
+            // sufficient pow for our usecase: 100 sextillion expected hashes
+            let utu = IUtuRelayDispatcher { contract_address: self.utu_address.read() };
+            utu.assert_safe(block_height, block_header.hash(), 100_000_000_000_000_000_000_000, 0);
 
             // if all good, we update the receiver
             self.depositor.write(get_caller_address());