IB20.updatePolicy

Binds a Policy Registry policy ID to a policy scope on a B20 token.

Signature

IB20.sol

function updatePolicy(bytes32 policyScope, uint64 newPolicyId) external;

Field	Value
Selector	0xadf9c4ea
Canonical signature	updatePolicy(bytes32,uint64)

Description

Binds newPolicyId to policyScope. Takes effect immediately: the next operation that consults that scope calls isAuthorized(newPolicyId, account) on the Policy Registry. Emits PolicyUpdated.

Until a scope is updated it holds 0 (ALWAYS_ALLOW), so the check passes for every address.

Parameters

Parameter	Description
policyScope	The scope slot to update. Must be a scope this token recognizes.
newPolicyId	The policy ID to assign. Must be a built-in sentinel (ALWAYS_ALLOW, ALWAYS_BLOCK), an existing registry policy, or an inverted ID whose base policy exists. The token treats the value as an opaque uint64.

Reverts

Error	Condition
AccessControlUnauthorizedAccount	Caller does not hold DEFAULT_ADMIN_ROLE.
UnsupportedPolicyType(policyScope)	policyScope is not a slot this token supports.
PolicyNotFound(newPolicyId)	newPolicyId is not a built-in sentinel and does not exist in the registry. An inverted ID is valid when its base exists, because policyExists strips bit 63 before checking.

Access Control

DEFAULT_ADMIN_ROLE gates this call. During token creation, initCalls may bind policies in the same transaction; those calls bypass the role gate.

Policy Scopes

The recognized scopes and the accounts they check are:

Scope	Checked account	Denies when isAuthorized is
TRANSFER_SENDER_POLICY	from	false
TRANSFER_RECEIVER_POLICY	to	false
TRANSFER_EXECUTOR_POLICY	msg.sender (on transferFrom when msg.sender != from)	false
MINT_RECEIVER_POLICY	to	false
SEIZE_EXEMPT_POLICY	from	true
SEIZE_RECEIVER_POLICY	to	false

Transfer scopes are skipped on factory initCalls transfers. MINT_RECEIVER_POLICY is always checked, including factory initCalls mints. SEIZE_EXEMPT_POLICY unset (ALWAYS_ALLOW) means no account is seizable.

Inverted Policy IDs

Bit 63 of a uint64 policy ID is the invert (NOT) flag. Passing an inverted ID to updatePolicy is valid as long as the base policy (the ID with bit 63 cleared) exists in the registry. The token stores and passes the full uint64 — including the invert bit — to isAuthorized, which returns the opposite of the base policy’s decision. If the base does not exist at evaluation time, isAuthorized returns false (fail-closed).

Use invertedPolicyId(policyId) on the Policy Registry to toggle the bit rather than computing it manually.

Example

Usage Example

IB20(token).updatePolicy(B20Constants.TRANSFER_RECEIVER_POLICY, policyId);

Inverted Policy Example

uint64 notExcluded = IPolicyRegistry(registry).invertedPolicyId(exclusionId);
IB20(token).updatePolicy(B20Constants.TRANSFER_RECEIVER_POLICY, notExcluded);

The same policy ID can be bound to more than one scope and to more than one token. Updating membership in the registry policy is visible immediately on every scope and token that references it; no second updatePolicy call is needed.