Offline access for vehicles

1 . A method comprising:

receiving, by a server computer from a first communication device, an access request message comprising a second user identifier from a first user to access a vehicle, the vehicle associated with a second user;

transmitting, by the server computer an authorization request message comprising a credential or a token associated with the first user to an authorizing entity computer;

receiving, by the server computer from the authorizing entity computer, an authorization response message; and

responsive to receiving the authorization response message, transmitting, by the server computer the credential or the token to the vehicle, wherein the first user is able to access the vehicle by presenting a user device that contains the credential or token to the vehicle,

wherein the vehicle receives the credential or token from the user device, and the vehicle automatically grants access to the vehicle to the second user in response to receiving the credential or token in an offline dynamic authentication process, the offline dynamic authentication process comprising:

transmitting, by the vehicle to the user device, dynamic data, wherein the user device cryptographically signs the credential or token and the dynamic data with a user device private key to form a dynamic digital signature; and

verifying, by the vehicle, the dynamic digital signature with a user device public key corresponding to the user device private key.

2 . The method of claim 1 , wherein the vehicle is a car and the user device is a mobile phone.

3 . The method of claim 1 , further comprising:

transmitting, by the server computer, a request to approve use of the vehicle to a second communication device operated by the second user; and

receiving, by the server computer, a response to the request to approve the use of the vehicle from the second communication device.

4 . The method of claim 1 , further comprising:

transmitting, by the server computer, a credential request message to the first communication device; and

receiving, by the server computer, a credential response message comprising the credential or token, and driver's license and insurance data, from the first communication device.

5 . The method of claim 1 , wherein the authorization request message comprises the credential.

6 . The method of claim 1 , wherein the vehicle receives an authorizing entity public key certificate from the user device, and extracts an authorizing entity public key from the authorizing entity public key certificate, and wherein the vehicle receives a user device public key certificate from the user device, verifies the user device public key certificate using the authorizing entity public key, and extracts the user device public key from the user device public key certificate.

7 . The method of claim 6 , wherein the vehicle receives a certificate authority public key from a certificate authority computer, and wherein the vehicle uses the certificate authority public key to verify the authorizing entity public key certificate before extracting the authorizing entity public key from the authorizing entity public key certificate.

8 . The method of claim 1 , wherein the vehicle and the user device communicate via NFC.

9 . The method of claim 8 , wherein the user device is a card.

10 . The method of claim 1 , wherein the first communication device is a mobile phone and the user device is a card.

11 . The method of claim 1 , wherein the first communication device and the user device are the same.

12 . The method of claim 1 , wherein the first user is remotely located with respect to the second user.

13 . A system comprising:

one or more processors; and

one or more computer readable media comprising code, executable by the one or more processors, for performing a method comprising:

receiving, from a first communication device, an access request message comprising a second user identifier from a first user to access a vehicle, the vehicle associated with a second user;

transmitting an authorization request message comprising a credential or a token associated with the first user to an authorizing entity computer;

receiving, from the authorizing entity computer, an authorization response message; and

responsive to receiving the authorization response message, transmitting, the credential or the token to the vehicle, wherein the first user is able to access the vehicle by presenting a user device that contains the credential or token to the vehicle,

wherein the vehicle is programmed to receive the credential or token from the user device, and automatically grant access to the vehicle to the second user in response to receiving the credential or token in an offline dynamic authentication process, the offline dynamic authentication process comprising:

transmitting, by the vehicle to the user device, dynamic data, wherein the user device cryptographically signs the credential or token and the dynamic data with a user device private key to form a dynamic digital signature; and

verifying, by the vehicle, the dynamic digital signature with a user device public key corresponding to the user device private key.

14 . A method comprising:

receiving, by a vehicle, a credential or token from a user device;

determining, by the vehicle, that the credential or the token was previously received from a server computer;

performing, by the vehicle, an offline data authentication process with the user device; and

allowing access to the vehicle after the offline data authentication process is performed,

wherein the offline data authentication process comprises:

transmitting, by the vehicle to the user device, dynamic data, wherein the user device cryptographically signs the credential or token and the dynamic data with a user device private key to form a dynamic digital signature; and

verifying, by the vehicle, the dynamic digital signature with a user device public key corresponding to the user device private key.

15 . The method according to claim 14 , wherein the vehicle receives the credential.

16 . The method of claim 14 , wherein the method is performed when the vehicle is a car.

17 . The method of claim 14 , wherein the user device is a card.

18 . The method of claim 17 , wherein the card is a payment card.

19 . The method of claim 1 , wherein the authorization request message comprises the credential, and the credential is transmitted by the server computer to the vehicle, the credential being a credit card or debit card number.

20 . The method of claim 1 , wherein the authorization request message comprises the token, and the token is transmitted by the server computer to the vehicle, the token being a payment token.