ethereum.prague.vm.eoa_delegation
Set EOA account code.
SET_CODE_TX_MAGIC
22 | SET_CODE_TX_MAGIC = b"\x05" |
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EOA_DELEGATION_MARKER
23 | EOA_DELEGATION_MARKER = b"\xEF\x01\x00" |
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EOA_DELEGATION_MARKER_LENGTH
24 | EOA_DELEGATION_MARKER_LENGTH = len(EOA_DELEGATION_MARKER) |
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EOA_DELEGATED_CODE_LENGTH
25 | EOA_DELEGATED_CODE_LENGTH = 23 |
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PER_EMPTY_ACCOUNT_COST
26 | PER_EMPTY_ACCOUNT_COST = 25000 |
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PER_AUTH_BASE_COST
27 | PER_AUTH_BASE_COST = 12500 |
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NULL_ADDRESS
28 | NULL_ADDRESS = hex_to_address("0x0000000000000000000000000000000000000000") |
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is_valid_delegation
Whether the code is a valid delegation designation.
Parameters
code: bytes
The code to check.
Returns
valid : bool
True if the code is a valid delegation designation,
False otherwise.
def is_valid_delegation(code: bytes) -> bool:
32 | """ |
---|---|
33 | Whether the code is a valid delegation designation. |
34 |
|
35 | Parameters |
36 | ---------- |
37 | code: `bytes` |
38 | The code to check. |
39 |
|
40 | Returns |
41 | ------- |
42 | valid : `bool` |
43 | True if the code is a valid delegation designation, |
44 | False otherwise. |
45 | """ |
46 | if ( |
47 | len(code) == EOA_DELEGATED_CODE_LENGTH |
48 | and code[:EOA_DELEGATION_MARKER_LENGTH] == EOA_DELEGATION_MARKER |
49 | ): |
50 | return True |
51 | return False |
get_delegated_code_address
Get the address to which the code delegates.
Parameters
code: bytes
The code to get the address from.
Returns
address : Optional[Address]
The address of the delegated code.
def get_delegated_code_address(code: bytes) -> Optional[Address]:
55 | """ |
---|---|
56 | Get the address to which the code delegates. |
57 |
|
58 | Parameters |
59 | ---------- |
60 | code: `bytes` |
61 | The code to get the address from. |
62 |
|
63 | Returns |
64 | ------- |
65 | address : `Optional[Address]` |
66 | The address of the delegated code. |
67 | """ |
68 | if is_valid_delegation(code): |
69 | return Address(code[EOA_DELEGATION_MARKER_LENGTH:]) |
70 | return None |
access_delegation
Get the delegation address, code, and the cost of access from the address.
Parameters
evm : Evm
The execution frame.
address : Address
The address to get the delegation from.
Returns
delegation : Tuple[bool, Address, Bytes, Uint]
The delegation address, code, and access gas cost.
def access_delegation(evm: Evm, address: Address) -> Tuple[bool, Address, Bytes, Uint]:
118 | """ |
---|---|
119 | Get the delegation address, code, and the cost of access from the address. |
120 |
|
121 | Parameters |
122 | ---------- |
123 | evm : `Evm` |
124 | The execution frame. |
125 | address : `Address` |
126 | The address to get the delegation from. |
127 |
|
128 | Returns |
129 | ------- |
130 | delegation : `Tuple[bool, Address, Bytes, Uint]` |
131 | The delegation address, code, and access gas cost. |
132 | """ |
133 | state = evm.message.block_env.state |
134 | code = get_account(state, address).code |
135 | if not is_valid_delegation(code): |
136 | return False, address, code, Uint(0) |
137 | |
138 | address = Address(code[EOA_DELEGATION_MARKER_LENGTH:]) |
139 | if address in evm.accessed_addresses: |
140 | access_gas_cost = GAS_WARM_ACCESS |
141 | else: |
142 | evm.accessed_addresses.add(address) |
143 | access_gas_cost = GAS_COLD_ACCOUNT_ACCESS |
144 | code = get_account(state, address).code |
145 | |
146 | return True, address, code, access_gas_cost |
set_delegation
Set the delegation code for the authorities in the message.
Parameters
message : Transaction specific items. env : External items required for EVM execution.
Returns
refund_counter: U256
Refund from authority which already exists in state.
def set_delegation(message: Message) -> U256:
150 | """ |
---|---|
151 | Set the delegation code for the authorities in the message. |
152 |
|
153 | Parameters |
154 | ---------- |
155 | message : |
156 | Transaction specific items. |
157 | env : |
158 | External items required for EVM execution. |
159 |
|
160 | Returns |
161 | ------- |
162 | refund_counter: `U256` |
163 | Refund from authority which already exists in state. |
164 | """ |
165 | state = message.block_env.state |
166 | refund_counter = U256(0) |
167 | for auth in message.tx_env.authorizations: |
168 | if auth.chain_id not in (message.block_env.chain_id, U256(0)): |
169 | continue |
170 |
|
171 | if auth.nonce >= U64.MAX_VALUE: |
172 | continue |
173 |
|
174 | try: |
175 | authority = recover_authority(auth) |
176 | except InvalidSignatureError: |
177 | continue |
178 |
|
179 | message.accessed_addresses.add(authority) |
180 |
|
181 | authority_account = get_account(state, authority) |
182 | authority_code = authority_account.code |
183 |
|
184 | if authority_code and not is_valid_delegation(authority_code): |
185 | continue |
186 |
|
187 | authority_nonce = authority_account.nonce |
188 | if authority_nonce != auth.nonce: |
189 | continue |
190 |
|
191 | if account_exists(state, authority): |
192 | refund_counter += U256(PER_EMPTY_ACCOUNT_COST - PER_AUTH_BASE_COST) |
193 |
|
194 | if auth.address == NULL_ADDRESS: |
195 | code_to_set = b"" |
196 | else: |
197 | code_to_set = EOA_DELEGATION_MARKER + auth.address |
198 | set_code(state, authority, code_to_set) |
199 |
|
200 | increment_nonce(state, authority) |
201 | |
202 | if message.code_address is None: |
203 | raise InvalidBlock("Invalid type 4 transaction: no target") |
204 | |
205 | message.code = get_account(state, message.code_address).code |
206 | |
207 | return refund_counter |