seal: Rework contracts API (#6573)

* Transition getter functions to not use scratch buffer * Remove scratch buffer from ext_get_storage * Remove scratch buffer from ext_call * Remove scratch buffer from ext_instantiate * Add ext_input and remove scratch buffer * Rework error handling (changes RPC exposed data) * ext_return passes a flags field instead of a return code * Flags is only for seal and not for the caller * flags: u32 replaced status_code: u8 in RPC exposed type * API functions use a unified error type (ReturnCode) * ext_transfer now traps on error to be consistent with call and instantiate * Remove the no longer used `Dispatched` event * Updated inline documentation * Prevent skipping of copying the output for getter API * Return gas_consumed from the RPC contracts call interface * Updated COMPLEXTITY.md * Rename ext_gas_price to ext_weight_to_fee * Align comments with spaces * Removed no longer used `ExecError` * Remove possible panic in `from_typed_value` * Use a struct as associated data for SpecialTrap::Return * Fix nits in COMPLEXITY.md * Renamed SpecialTrap to TrapReason * Fix test * Finish renaming special_trap -> trap_reason * Remove no longer used get_runtime_storage * fixup! Remove no longer used get_runtime_storage * Removed tabs for comment aligment
paritytech · Jul 9, 2020 · 37500ce · 37500ce
1 parent 7f12fd9
commit 37500ce
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diff --git a/Cargo.lock b/Cargo.lock
diff --git a/bin/node/executor/tests/basic.rs b/bin/node/executor/tests/basic.rs
@@ -491,32 +491,31 @@ const CODE_TRANSFER: &str = r#"
 ;;    value_ptr: u32,
 ;;    value_len: u32,
 ;;    input_data_ptr: u32,
-;;    input_data_len: u32
+;;    input_data_len: u32,
+;;    output_ptr: u32,
+;;    output_len_ptr: u32
 ;; ) -> u32
-(import "env" "ext_call" (func $ext_call (param i32 i32 i64 i32 i32 i32 i32) (result i32)))
-(import "env" "ext_scratch_size" (func $ext_scratch_size (result i32)))
-(import "env" "ext_scratch_read" (func $ext_scratch_read (param i32 i32 i32)))
+(import "env" "ext_call" (func $ext_call (param i32 i32 i64 i32 i32 i32 i32 i32 i32) (result i32)))
+(import "env" "ext_input" (func $ext_input (param i32 i32)))
 (import "env" "memory" (memory 1 1))
 (func (export "deploy")
 )
 (func (export "call")
 	(block $fail
-		;; load and check the input data (which is stored in the scratch buffer).
+		;; Load input data to contract memory
+		(call $ext_input
+			(i32.const 0)
+			(i32.const 52)
+		)
+
 		;; fail if the input size is not != 4
 		(br_if $fail
 			(i32.ne
 				(i32.const 4)
-				(call $ext_scratch_size)
+				(i32.load (i32.const 52))
 			)
 		)
 
-		(call $ext_scratch_read
-			(i32.const 0)
-			(i32.const 0)
-			(i32.const 4)
-		)
-
-
 		(br_if $fail
 			(i32.ne
 				(i32.load8_u (i32.const 0))
@@ -551,6 +550,8 @@ const CODE_TRANSFER: &str = r#"
 				(i32.const 16)   ;; Length of the buffer with value to transfer.
 				(i32.const 0)   ;; Pointer to input data buffer address
 				(i32.const 0)   ;; Length of input data buffer
+				(i32.const 4294967295) ;; u32 max value is the sentinel value: do not copy output
+				(i32.const 0) ;; Length is ignored in this case
 			)
 		)
 
@@ -571,6 +572,8 @@ const CODE_TRANSFER: &str = r#"
 	"\06\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00"
 	"\00\00"
 )
+;; Length of the input buffer
+(data (i32.const 52) "\04")
 )
 "#;
 

diff --git a/bin/node/runtime/src/lib.rs b/bin/node/runtime/src/lib.rs
@@ -1066,12 +1066,13 @@ impl_runtime_apis! {
 			gas_limit: u64,
 			input_data: Vec<u8>,
 		) -> ContractExecResult {
-			let exec_result =
+			let (exec_result, gas_consumed) =
 				Contracts::bare_call(origin, dest.into(), value, gas_limit, input_data);
 			match exec_result {
 				Ok(v) => ContractExecResult::Success {
-					status: v.status,
+					flags: v.flags.bits(),
 					data: v.data,
+					gas_consumed: gas_consumed,
 				},
 				Err(_) => ContractExecResult::Error,
 			}

diff --git a/frame/contracts/COMPLEXITY.md b/frame/contracts/COMPLEXITY.md
diff --git a/frame/contracts/Cargo.toml b/frame/contracts/Cargo.toml
@@ -25,6 +25,7 @@ sp-sandbox = { version = "0.8.0-rc4", default-features = false, path = "../../pr
 frame-support = { version = "2.0.0-rc4", default-features = false, path = "../support" }
 frame-system = { version = "2.0.0-rc4", default-features = false, path = "../system" }
 pallet-contracts-primitives = { version = "2.0.0-rc4", default-features = false, path = "common" }
+bitflags = "1.0"
 
 [dev-dependencies]
 wabt = "0.9.2"

diff --git a/frame/contracts/fixtures/caller_contract.wat b/frame/contracts/fixtures/caller_contract.wat
@@ -1,9 +1,8 @@
 (module
-	(import "env" "ext_scratch_size" (func $ext_scratch_size (result i32)))
-	(import "env" "ext_scratch_read" (func $ext_scratch_read (param i32 i32 i32)))
-	(import "env" "ext_balance" (func $ext_balance))
-	(import "env" "ext_call" (func $ext_call (param i32 i32 i64 i32 i32 i32 i32) (result i32)))
-	(import "env" "ext_instantiate" (func $ext_instantiate (param i32 i32 i64 i32 i32 i32 i32) (result i32)))
+	(import "env" "ext_input" (func $ext_input (param i32 i32)))
+	(import "env" "ext_balance" (func $ext_balance (param i32 i32)))
+	(import "env" "ext_call" (func $ext_call (param i32 i32 i64 i32 i32 i32 i32 i32 i32) (result i32)))
+	(import "env" "ext_instantiate" (func $ext_instantiate (param i32 i32 i64 i32 i32 i32 i32 i32 i32 i32 i32) (result i32)))
 	(import "env" "ext_println" (func $ext_println (param i32 i32)))
 	(import "env" "memory" (memory 1 1))
 
@@ -17,14 +16,16 @@
 	)
 
 	(func $current_balance (param $sp i32) (result i64)
-		(call $ext_balance)
-		(call $assert
-			(i32.eq (call $ext_scratch_size) (i32.const 8))
+		(i32.store
+			(i32.sub (get_local $sp) (i32.const 16))
+			(i32.const 8)
 		)
-		(call $ext_scratch_read
+		(call $ext_balance
 			(i32.sub (get_local $sp) (i32.const 8))
-			(i32.const 0)
-			(i32.const 8)
+			(i32.sub (get_local $sp) (i32.const 16))
+		)
+		(call $assert
+			(i32.eq (i32.load (i32.sub (get_local $sp) (i32.const 16))) (i32.const 8))
 		)
 		(i64.load (i32.sub (get_local $sp) (i32.const 8)))
 	)
@@ -36,21 +37,20 @@
 		(local $exit_code i32)
 		(local $balance i64)
 
+		;; Length of the buffer
+		(i32.store (i32.const 20) (i32.const 32))
+
+		;; Copy input to this contracts memory
+		(call $ext_input (i32.const 24) (i32.const 20))
+
 		;; Input data is the code hash of the contract to be deployed.
 		(call $assert
 			(i32.eq
-				(call $ext_scratch_size)
+				(i32.load (i32.const 20))
 				(i32.const 32)
 			)
 		)
 
-		;; Copy code hash from scratch buffer into this contract's memory.
-		(call $ext_scratch_read
-			(i32.const 24)		;; The pointer where to store the scratch buffer contents,
-			(i32.const 0)		;; Offset from the start of the scratch buffer.
-			(i32.const 32)		;; Count of bytes to copy.
-		)
-
 		;; Read current balance into local variable.
 		(set_local $sp (i32.const 1024))
 		(set_local $balance
@@ -67,17 +67,16 @@
 				(i32.const 8)	;; Length of the buffer with value to transfer.
 				(i32.const 9)	;; Pointer to input data buffer address
 				(i32.const 7)	;; Length of input data buffer
+				(i32.const 4294967295) ;; u32 max sentinel value: do not copy address
+				(i32.const 0) ;; Length is ignored in this case
+				(i32.const 4294967295) ;; u32 max sentinel value: do not copy output
+				(i32.const 0) ;; Length is ignored in this case
 			)
 		)
 
 		;; Check non-zero exit status.
 		(call $assert
-			(i32.eq (get_local $exit_code) (i32.const 0x11))
-		)
-
-		;; Check that scratch buffer is empty since contract instantiation failed.
-		(call $assert
-			(i32.eq (call $ext_scratch_size) (i32.const 0))
+			(i32.eq (get_local $exit_code) (i32.const 2)) ;; ReturnCode::CalleeReverted
 		)
 
 		;; Check that balance has not changed.
@@ -95,24 +94,29 @@
 				(i32.const 8)	;; Length of the buffer with value to transfer.
 				(i32.const 8)	;; Pointer to input data buffer address
 				(i32.const 8)	;; Length of input data buffer
+				(i32.const 4294967295) ;; u32 max sentinel value: do not copy address
+				(i32.const 0) ;; Length is ignored in this case
+				(i32.const 4294967295) ;; u32 max sentinel value: do not copy output
+				(i32.const 0) ;; Length is ignored in this case
 			)
 		)
 
 		;; Check for special trap exit status.
 		(call $assert
-			(i32.eq (get_local $exit_code) (i32.const 0x0100))
-		)
-
-		;; Check that scratch buffer is empty since contract instantiation failed.
-		(call $assert
-			(i32.eq (call $ext_scratch_size) (i32.const 0))
+			(i32.eq (get_local $exit_code) (i32.const 1)) ;; ReturnCode::CalleeTrapped
 		)
 
 		;; Check that balance has not changed.
 		(call $assert
 			(i64.eq (get_local $balance) (call $current_balance (get_local $sp)))
 		)
 
+		;; Length of the output buffer
+		(i32.store
+			(i32.sub (get_local $sp) (i32.const 4))
+			(i32.const 8)
+		)
+
 		;; Deploy the contract successfully.
 		(set_local $exit_code
 			(call $ext_instantiate
@@ -123,24 +127,22 @@
 				(i32.const 8)	;; Length of the buffer with value to transfer.
 				(i32.const 8)	;; Pointer to input data buffer address
 				(i32.const 8)	;; Length of input data buffer
+				(i32.const 16) ;; Pointer to the address output buffer
+				(i32.sub (get_local $sp) (i32.const 4)) ;; Pointer to the address buffer length
+				(i32.const 4294967295) ;; u32 max sentinel value: do not copy output
+				(i32.const 0) ;; Length is ignored in this case
+
 			)
 		)
 
 		;; Check for success exit status.
 		(call $assert
-			(i32.eq (get_local $exit_code) (i32.const 0x00))
+			(i32.eq (get_local $exit_code) (i32.const 0)) ;; ReturnCode::Success
 		)
 
-		;; Check that scratch buffer contains the address of the new contract.
+		;; Check that address has the expected length
 		(call $assert
-			(i32.eq (call $ext_scratch_size) (i32.const 8))
-		)
-
-		;; Copy contract address from scratch buffer into this contract's memory.
-		(call $ext_scratch_read
-			(i32.const 16)		;; The pointer where to store the scratch buffer contents,
-			(i32.const 0)		;; Offset from the start of the scratch buffer.
-			(i32.const 8)		;; Count of bytes to copy.
+			(i32.eq (i32.load (i32.sub (get_local $sp) (i32.const 4))) (i32.const 8))
 		)
 
 		;; Check that balance has been deducted.
@@ -151,6 +153,18 @@
 			(i64.eq (get_local $balance) (call $current_balance (get_local $sp)))
 		)
 
+		;; Zero out destination buffer of output
+		(i32.store
+			(i32.sub (get_local $sp) (i32.const 4))
+			(i32.const 0)
+		)
+
+		;; Length of the output buffer
+		(i32.store
+			(i32.sub (get_local $sp) (i32.const 8))
+			(i32.const 4)
+		)
+
 		;; Call the new contract and expect it to return failing exit code.
 		(set_local $exit_code
 			(call $ext_call
@@ -161,26 +175,19 @@
 				(i32.const 8)	;; Length of the buffer with value to transfer.
 				(i32.const 9)	;; Pointer to input data buffer address
 				(i32.const 7)	;; Length of input data buffer
+				(i32.sub (get_local $sp) (i32.const 4)) ;; Ptr to output buffer
+				(i32.sub (get_local $sp) (i32.const 8)) ;; Ptr to output buffer len
 			)
 		)
 
 		;; Check non-zero exit status.
 		(call $assert
-			(i32.eq (get_local $exit_code) (i32.const 0x11))
+			(i32.eq (get_local $exit_code) (i32.const 2)) ;; ReturnCode::CalleeReverted
 		)
 
-		;; Check that scratch buffer contains the expected return data.
+		;; Check that output buffer contains the expected return data.
 		(call $assert
-			(i32.eq (call $ext_scratch_size) (i32.const 3))
-		)
-		(i32.store
-			(i32.sub (get_local $sp) (i32.const 4))
-			(i32.const 0)
-		)
-		(call $ext_scratch_read
-			(i32.sub (get_local $sp) (i32.const 4))
-			(i32.const 0)
-			(i32.const 3)
+			(i32.eq (i32.load (i32.sub (get_local $sp) (i32.const 8))) (i32.const 3))
 		)
 		(call $assert
 			(i32.eq
@@ -204,24 +211,33 @@
 				(i32.const 8)	;; Length of the buffer with value to transfer.
 				(i32.const 8)	;; Pointer to input data buffer address
 				(i32.const 8)	;; Length of input data buffer
+				(i32.const 4294967295) ;; u32 max sentinel value: do not copy output
+				(i32.const 0) ;; Length is ignored in this cas
 			)
 		)
 
 		;; Check for special trap exit status.
 		(call $assert
-			(i32.eq (get_local $exit_code) (i32.const 0x0100))
-		)
-
-		;; Check that scratch buffer is empty since call trapped.
-		(call $assert
-			(i32.eq (call $ext_scratch_size) (i32.const 0))
+			(i32.eq (get_local $exit_code) (i32.const 1)) ;; ReturnCode::CalleeTrapped
 		)
 
 		;; Check that balance has not changed.
 		(call $assert
 			(i64.eq (get_local $balance) (call $current_balance (get_local $sp)))
 		)
 
+		;; Zero out destination buffer of output
+		(i32.store
+			(i32.sub (get_local $sp) (i32.const 4))
+			(i32.const 0)
+		)
+
+		;; Length of the output buffer
+		(i32.store
+			(i32.sub (get_local $sp) (i32.const 8))
+			(i32.const 4)
+		)
+
 		;; Call the contract successfully.
 		(set_local $exit_code
 			(call $ext_call
@@ -232,26 +248,19 @@
 				(i32.const 8)	;; Length of the buffer with value to transfer.
 				(i32.const 8)	;; Pointer to input data buffer address
 				(i32.const 8)	;; Length of input data buffer
+				(i32.sub (get_local $sp) (i32.const 4)) ;; Ptr to output buffer
+				(i32.sub (get_local $sp) (i32.const 8)) ;; Ptr to output buffer len
 			)
 		)
 
 		;; Check for success exit status.
 		(call $assert
-			(i32.eq (get_local $exit_code) (i32.const 0x00))
+			(i32.eq (get_local $exit_code) (i32.const 0)) ;; ReturnCode::Success
 		)
 
-		;; Check that scratch buffer contains the expected return data.
+		;; Check that the output buffer contains the expected return data.
 		(call $assert
-			(i32.eq (call $ext_scratch_size) (i32.const 4))
-		)
-		(i32.store
-			(i32.sub (get_local $sp) (i32.const 4))
-			(i32.const 0)
-		)
-		(call $ext_scratch_read
-			(i32.sub (get_local $sp) (i32.const 4))
-			(i32.const 0)
-			(i32.const 4)
+			(i32.eq (i32.load (i32.sub (get_local $sp) (i32.const 8))) (i32.const 4))
 		)
 		(call $assert
 			(i32.eq
@@ -271,5 +280,5 @@
 
 	(data (i32.const 0) "\00\80")		;; The value to transfer on instantiation and calls.
 										;; Chosen to be greater than existential deposit.
-	(data (i32.const 8) "\00\11\22\33\44\55\66\77")		;; The input data to instantiations and calls.
+	(data (i32.const 8) "\00\01\22\33\44\55\66\77")		;; The input data to instantiations and calls.
 )