Abstract: It is provided a method for controlling access to a physical space using a co-sign delegation. The method is performed in a lock device and comprises the steps of: receiving an access request from an electronic key; obtaining a plurality of delegations, wherein each delegation is a delegation from a delegator to a delegatee, the plurality of delegations collectively forming a chain of delegations; determining that a delegation is a co-sign delegation, indicating that all further delegations need to be cryptographically signed by both the delegator of the respective delegation and by an access controller; and granting access to the physical space when the chain of delegations start in an owner of the lock device and ends in the electronic key; and when all delegations in the chain of delegations after the co-sign delegation are cryptographically signed by both the delegator of the respective delegation and by the access controller.

Abstract: It is provided a method for managing central secret keys of a plurality of user devices associated with a single public key. The method is performed in a key manager and comprises the steps of: receiving, from a first user device, transformation data and an identifier of a second user device; obtaining a first central secret key associated with the first user device; generating a second central secret key by applying the transformation data to the first central secret key, wherein the transformation data is applied in reverse to how the same transformation data is applied by the first user device to a device secret key of the first user device; and storing the second central secret key in association with the second user device.

Abstract: It is provided a method for controlling access to a physical space using a co-sign delegation. The method is performed in a lock device and comprises the steps of: receiving an access request from an electronic key; obtaining a plurality of delegations, wherein each delegation is a delegation from a delegator to a delegatee, the plurality of delegations collectively forming a chain of delegations; determining that a delegation is a co-sign delegation, indicating that all further delegations need to be cryptographically signed by both the delegator of the respective delegation and by an access controller; and granting access to the physical space when the chain of delegations start in an owner of the lock device and ends in the electronic key; and when all delegations in the chain of delegations after the co-sign delegation are cryptographically signed by both the delegator of the respective delegation and by the access controller.

Abstract: It is provided a method for controlling access to a physical space using an emergency delegation. The method is performed in a lock device and comprises the steps of: receiving an access request from an electronic key; obtaining a plurality of delegations, wherein each delegation is a delegation from a delegator to a delegatee, the plurality of delegations collectively forming a chain of delegations wherein when two delegations are chained together, the delegatee of one delegation is the delegator of the next delegation; determining that a delegation in the chain of delegations is an emergency delegation, the emergency delegation indicating that access should only be granted when an emergency situation occurs; determining when an emergency situation occurs; and granting access to the physical space when the chain of delegations starts in the lock device and ends in the electronic key; and when the emergency situation occurs.

Abstract: It is presented a method for controlling access to an access object. The method is performed in an access control device and comprises the steps of: receiving a user input to reset the access control device; generating a new identifier for the access control device, and discarding any previously used identifier for the access control device; communicating with an electronic key to obtain an identity of the electronic key; obtaining a plurality of delegations, wherein each delegation is a delegation from a delegator to a receiver; and granting access to the access object only when the plurality of delegations comprise a sequence of delegations covering a delegation path from the access control device, identified using the new identifier, to the electronic key such that, in the sequence of delegations, the delegator of the first delegation is the access control device, and the receiver of the last delegation is the electronic key.

Abstract: It is provided a method for controlling access to a physical space using a co-sign delegation. The method is performed in a lock device and comprises the steps of: receiving an access request from an electronic key; obtaining a plurality of delegations, wherein each delegation is a delegation from a delegator to a delegatee, the plurality of delegations collectively forming a chain of delegations; determining that a delegation is a co-sign delegation, indicating that all further delegations need to be cryptographically signed by both the delegator of the respective delegation and by an access controller; and granting access to the physical space when the chain of delegations start in an owner of the lock device and ends in the electronic key; and when all delegations in the chain of delegations after the co-sign delegation are cryptographically signed by both the delegator of the respective delegation and by the access controller.

Abstract: It is provided a method for controlling access to a physical space using a co-sign delegation. The method is performed in a lock device and comprises the steps of: receiving an access request from an electronic key; obtaining a plurality of delegations, wherein each delegation is a delegation from a delegator to a delegatee, the plurality of delegations collectively forming a chain of delegations; determining that a delegation is a co-sign delegation, indicating that all further delegations need to be cryptographically signed by both the delegator of the respective delegation and by an access controller; and granting access to the physical space when the chain of delegations start in an owner of the lock device and ends in the electronic key; and when all delegations in the chain of delegations after the co-sign delegation are cryptographically signed by both the delegator of the respective delegation and by the access controller.

Abstract: it is provided a method for performing a cryptographic signing operation of a data item. The method is performed in a server and comprises the steps of: receiving, from a smartcard reader, a request for a data item to be collectively signed, the request comprising an indication of the data item and an identifier of a smartcard, wherein the collective signing requires the use of both a smartcard secret key and a server secret key for the collective signature to be valid; establishing a secure channel with the smartcard; collaborating with the smartcard over the secure channel to provide a collective signature of the data item, wherein the server bases the signature on the data item and a server secret key, wherein the server secret key is specifically associated with the smartcard secret key, resulting in a collective signature; and sending the collective signature to the smartcard reader.

Abstract: It is provided a method for controlling access to an access object. The method is performed in an electronic key device and comprises the steps of: communicating with an access control device to obtain an identity of the access control device; sending an access request to a server, the access request comprising an identity of the electronic key device and the identity of the access control device; receiving a response from the server, the response comprising a key delegation to the electronic key device; and sending a grant access request to the access control device, the grant access request comprising the key delegation, to allow the access control device to evaluate whether to grant access to the access object based on a plurality of delegations comprising a sequence of delegations.

Abstract: It is provided a method for controlling access to an access object. The method is performed in an electronic key device and comprises the steps of: communicating with an access control device to obtain an identity of the access control device; sending an access request to a server, the access request comprising an identity of the electronic key device and the identity of the access control device; receiving a response from the server, the response comprising a key delegation to the electronic key device; and sending a grant access request to the access control device, the grant access request comprising the key delegation, to allow the access control device to evaluate whether to grant access to the access object based on a plurality of delegations comprising a sequence of delegations.

Abstract: It is provided a method for controlling access to a physical space using an emergency delegation. The method is performed in a lock device and comprises the steps of: receiving an access request from an electronic key; obtaining a plurality of delegations, wherein each delegation is a delegation from a delegator to a delegatee, the plurality of delegations collectively forming a chain of delegations wherein when two delegations are chained together, the delegatee of one delegation is the delegator of the next delegation; determining that a delegation in the chain of delegations is an emergency delegation, the emergency delegation indicating that access should only be granted when an emergency situation occurs; determining when an emergency situation occurs; and granting access to the physical space when the chain of delegations starts in the lock device and ends in the electronic key; and when the emergency situation occurs.

Abstract: It is provided a method for controlling access to a physical space. The method is performed in an access control device and comprises the steps of: communicating with an electronic key to obtain an identity of the electronic key; obtaining a plurality of delegations; determining, from one of the delegations, that there is an auxiliary condition, wherein the auxiliary condition is that access is approved for the electronic key by an auxiliary party, authenticated by a digital signature by the auxiliary party; and granting access to the physical space when the plurality of delegations comprises a sequence of delegations covering a delegation path from the access control device to the electronic key such that, in the sequence of delegations, the delegator of the first delegation is the access control device, the receiver of the last delegation is the electronic key, and the auxiliary condition is fulfilled.

Abstract: It is provided a method for controlling access to a physical space using a co-sign delegation. The method is performed in a lock device and comprises the steps of: receiving an access request from an electronic key; obtaining a plurality of delegations, wherein each delegation is a delegation from a delegator to a delegatee, the plurality of delegations collectively forming a chain of delegations; determining that a delegation is a co-sign delegation, indicating that all further delegations need to be cryptographically signed by both the delegator of the respective delegation and by an access controller; and granting access to the physical space when the chain of delegations start in an owner of the lock device and ends in the S electronic key; and when all delegations in the chain of delegations after the co-sign delegation are cryptographically signed by both the delegator of the respective delegation and by the access controller.

Abstract: It is presented a method for determining whether a user with a credential should be granted access to a physical space. The method is performed in an access control device and comprising identifying the credential presented to the access control device; obtaining a set of at least one assignment of a permission, associated with the physical space, to external organisations from a database; determining a credential organisation being associated with the credential; and granting access when, and only when, the permission is assigned to the credential organisation.

Abstract: It is presented a method for controlling access to an access object. The method is performed in an access control device and comprises the steps of: receiving a user input to reset the access control device; generating a new identifier for the access control device, and discarding any previously used identifier for the access control device; communicating with an electronic key to obtain an identity of the electronic key; obtaining a plurality of delegations, wherein each delegation is a delegation from a delegator to a receiver; and granting access to the access object only when the plurality of delegations comprise a sequence of delegations covering a delegation path from the access control device, identified using the new identifier, to the electronic key such that, in the sequence of delegations, the delegator of the first delegation is the access control device, and the receiver of the last delegation is the electronic key.

Abstract: It is presented a method for determining whether a user with a credential should be granted access to a physical space. The method is performed in an access control device and comprising the steps of: identifying the credential presented to the access control device; obtaining a set of at least one assignment of a permission, associated with the physical space, to external organisations from a database; determining a credential organisation being associated with the credential; and granting access when, and only when, the permission is assigned to the credential organisation.

Abstract: It is provided a method for managing central secret keys of a plurality of user devices associated with a single public key. The method is performed in a key manager and comprises the steps of: receiving, from a first user device, transformation data and an identifier of a second user device; obtaining a first central secret key associated with the first user device; generating a second central secret key by applying the transformation data to the first central secret key, wherein the transformation data is applied in reverse to how the same transformation data is applied by the first user device to a device secret key of the first user device; and storing the second central secret key in association with the second user device.

Abstract: It is presented a method for controlling access to an access object. The method is performed in an access control device and comprises the steps of: receiving a user input to reset the access control device; generating a new identifier for the access control device, and discarding any previously used identifier for the access control device; communicating with an electronic key to obtain an identity of the electronic key; obtaining a plurality of delegations, wherein each delegation is a delegation from a delegator to a receiver; and granting access to the access object only when the plurality of delegations comprise a sequence of delegations covering a delegation path from the access control device, identified using the new identifier, to the electronic key such that, in the sequence of delegations, the delegator of the first delegation is the access control device, and the receiver of the last delegation is the electronic key.

Abstract: It is provided a method for controlling access to a physical space. The method is performed in an access control device and comprises the steps of: communicating with an electronic key to obtain an identity of the electronic key; obtaining a plurality of delegations; determining, from one of the delegations, that there is an auxiliary condition, wherein the auxiliary condition is that access is approved for the electronic key by an auxiliary party, authenticated by a digital signature by the auxiliary party; and granting access to the physical space when the plurality of delegations comprises a sequence of delegations covering a delegation path from the access control device to the electronic key such that, in the sequence of delegations, the delegator of the first delegation is the access control device, the receiver of the last delegation is the electronic key, and the auxiliary condition is fulfilled.

Abstract: It is presented a method for controlling access to an access object. The method is performed in an access control device and comprises the steps of: receiving a user input to reset the access control device; generating a new identifier for the access control device, and discarding any previously used identifier for the access control device; communicating with an electronic key to obtain an identity of the electronic key; obtaining a plurality of delegations, wherein each delegation is a delegation from a delegator to a receiver; and granting access to the access object only when the plurality of delegations comprise a sequence of delegations covering a delegation path from the access control device, identified using the new identifier,to the electronic key such that, in the sequence of delegations, the delegator of the first delegation is the access control device, and the receiver of the last delegation is the electronic key.